Publications

Chen, F, Zhou, J, Wang, Y, Yu, K, Arshad, SZ, Khawaji, A & Conway, D 2016, Robust Multimodal Cognitive Load Measurement, Springer, Switzerland.
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This book explores robust multimodal cognitive load measurement with physiological and behavioural modalities, which involve the eye, Galvanic Skin Response, speech, language, pen input, mouse movement and multimodality fusions.

Masihpour, M, Agbinya, JI & Abolhasan, M 2016, 'Design Issues in EM Energy Harvesting Systems' in Venkataraman, H & Muntean, GM (eds), Green Mobile Devices and Networks, CRC Press, USA, pp. 201-234.
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Energy scavenging dates back to the use of waterwheels and windmills to harvest the energy from the surrounding environment and convert it to useful forms of energy [1]. Energy scavenging techniques have been around for decades to provide electricity from different natural resources, such as wind power, water flow, heat, sunlight, and vibration. However, there has been a new interest in energy harvesting methods recently, due to the mass increase of wireless sensors and low power electronics [1]. Electronic devices, such as mobile phones, laptops, PDAs (Personal DigitalAssistants),medical implant devices, and differenttypes ofsensor nodes, all require a powersourceto operate.Therefore, they are providedwith eitherwires or disposable/rechargeable batteries to supply the power.Thanks to advanced fabrication technologies, very smallsized batteries areintroduced,which aresmallenough to belocated on a chip to power up a sensor node or a smallelectronic handheld [1]. The problem with batteries is that they havelimited lifetimes or they arerequired to berecharged on a regular basis. However, there have been technology advances to optimizethe battery performance and itslifetime,such as dynamic optimization of voltage and clock rate, hybrid analog digital designs, and clever wake up procedures that allow a deviceto go to inactive mode when it is not required to operate a task [1]

Smith, DB & Abolhasan, M 2016, 'Diversity and cooperative communications in body area networks' in Advances in Body-Centric Wireless Communication: Applications and state-of-the-art, Institution of Engineering and Technology, USA, pp. 7-42.
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In this chapter, we investigate diversity and cooperative communications, and particularly cooperative diversity, for body-centric communications in wireless body area networks (BANs). Cooperative diversity for BANs is vitally important for required communications reliability, as well as increasing network and sensor lifetime by potentially reducing energy consumption, as will be shown here. We describe what is meant by cooperative communications and cooperative diversity, including a brief survey of the state-of-the-art. Description and analysis of the benefits of cooperative diversity in BANs is mainly with respect to the physical layer, but there is also some brief discussion of the MAC layer and network layer. In terms of cooperative receive diversity, feasible in IEEE 802.15.6 Standard compliant BAN, several cooperative receive combining techniques are described, which are all beneficial over single-link communications in terms of firstand second-order statistics. A simple, practical, technique of switch-and-examine combining shows good performance in terms of important metrics, and this can be further enhanced when combined with a simple “sample-and-hold” transmit power control, which can help reduce energy consumption for sensor radios.

Abdullahi, S & Pradhan, B 2016, 'Sustainable Brownfields Land Use Change Modeling Using GIS-based Weights-of-Evidence Approach', Applied Spatial Analysis and Policy, vol. 9, no. 1, pp. 21-38.
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Abolhasan, M, Maali, Y, Rafiei, A & Ni, W 2016, 'Distributed Hybrid Coverage Hole Recovery in Wireless Sensor Networks', IEEE SENSORS JOURNAL, vol. 16, no. 23, pp. 8640-8648.
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© 2001-2012 IEEE. Coverage holes (CHs) can compromise the reliability and functionality of wireless sensor networks. The recovery of CHs is challenging, especially in distributed applications where sensors have little knowledge about other sensors' actions. We propose a new game theoretic approach for recovering the CHs in a distributed manner. The key idea is that we formulate a potential game between the sensors, where each mobile sensor in the network only depends on local knowledge of its neighboring nodes and takes CH recovery actions recursively with global convergence. An appropriate combined action of physical relocation and sensing range adjustment can be taken by each sensor to reduce the CHs in an energy-efficient way. Simulation results show that the proposed game theoretic approach is able to substantially increase network lifetime and maintain network coverage in the presence of random damage events, as compared with the prior counterpart(s).

Aghdam, IN, Varzandeh, MHM & Pradhan, B 2016, 'Landslide susceptibility mapping using an ensemble statistical index (Wi) and adaptive neuro-fuzzy inference system (ANFIS) model at Alborz Mountains (Iran)', Environmental Earth Sciences, vol. 75, no. 7, p. 553.
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Al-Abadi, AM, Pradhan, B & Shahid, S 2016, 'Prediction of groundwater flowing well zone at An-Najif Province, central Iraq using evidential belief functions model and GIS', Environmental Monitoring and Assessment, vol. 188, no. 10, p. 549.
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Alazigha, DP, Indraratna, B, Vinod, JS & Ezeajugh, LE 2016, 'The swelling behaviour of lignosulfonate-treated expansive soil', Proceedings of the Institution of Civil Engineers - Ground Improvement, vol. 169, no. 3, pp. 182-193.
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This paper presents results regarding the potential of lignosulfonate (LS) to control the swelling of expansive soil. One-dimensional swell tests were performed on untreated and LS-treated remoulded samples of Australian expansive soil from the state of Queensland. The test results indicated that LS has significant influence on the swelling behaviour of this expansive soil. The results were compared with those of identical cement-treated soil samples, and it was found that LS could be a economical and environmentally friendly alternative to traditional alkaline additives. In addition, the behaviour of LS-treated specimens during repeated freezing and thawing cycles was measured. The results indicated significant improvement in the percentage mass loss in LS-treated specimens compared with cement-treated specimens. The microstructural analysis of the untreated and the LS-treated samples showed soil surface area reduction in the treated specimens, which in turn reduced the affinity of the specimens towards moisture uptake, resulting in a reduction in the swell potential of the otherwise expansive soil. The use of LS as a novel non-traditional stabiliser for expansive soil appears to be a viable solution in view of the sustainable use of waste by-products and green construction.

Al-sharif, AAA & Pradhan, B 2016, 'Spatio-temporal Prediction of Urban Expansion Using Bivariate Statistical Models: Assessment of the Efficacy of Evidential Belief Functions and Frequency Ratio Models', Applied Spatial Analysis and Policy, vol. 9, no. 2, pp. 213-231.
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Althuwaynee, OF, Pradhan, B & Lee, S 2016, 'A novel integrated model for assessing landslide susceptibility mapping using CHAID and AHP pair-wise comparison', International Journal of Remote Sensing, vol. 37, no. 5, pp. 1190-1209.
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Askari, M, Li, J & Samali, B 2016, 'A compact self-adaptive recursive least square approach for real-time structural identification with unknown inputs', Advances in Structural Engineering, vol. 19, no. 7, pp. 1118-1129.
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A new online tracking technique, based on recursive least square with adaptive multiple forgetting factors, is presented in this article which can estimate abrupt changes in structural parameters during excitation and also identify the unknown inputs to the structure, for example, earthquake signal. The method considers an adaptive rule for each of the forgetting factors assigned to each of the unknown parameters and thus enables simultaneous identification of different time-varying parameters of the system. The method is validated through both linear and nonlinear case studies, with different excitations and damage scenarios. The results show that the proposed algorithm can effectively identify the time-varying parameters such as damping, stiffness as well as unknown excitations with high computational efficiency, even when the measured data are contaminated with different levels of noise. However, when damage occurs while the excitation is small, the identification error remains at a small range, and therefore, covariance cannot be amplified to effectively track the changes in unknown parameters.

Askari, M, Li, J & Samali, B 2016, 'Application of Kalman Filtering Methods to Online Real-Time Structural Identification: A Comparison Study', International Journal of Structural Stability and Dynamics, vol. 16, no. 06, pp. 1550016-1550016.
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System identification refers to the process of building or improving mathematical models of dynamical systems from the observed experimental input–output data. In the area of civil engineering, the estimation of the integrity of a structure under dynamic loadings and during service condition has become a challenge for the engineering community. Therefore, there has been a great deal of attention paid to online and real-time structural identification, especially when input–output measurement data are contaminated by high-level noise. Among real-time identification methods, one of the most successful and widely used algorithms for estimation of system states and parameters is the Kalman filter and its various nonlinear extensions such as extended Kalman filter (EKF), Iterated EKF (IEKF), the recently developed unscented Kalman filter (UKF) and Iterated UKF (IUKF). In this paper, an investigation has been carried out on the aforementioned techniques for their effectiveness and efficiencies through a highly nonlinear single degree of freedom (SDOF) structure as well as a two-storey linear structure. Although IEKF is an improved version of EKF, results show that IUKF generally produces better results in terms of structural parameters and state estimation than UKF and IEKF. Also IUKF is more robust to noise levels compared to the other approaches.

Askari, M, Li, J & Samali, B 2016, 'Semi-active control of smart building-MR damper systems using novel TSK-Inv and max-min algorithms', Smart Structures and Systems, vol. 18, no. 5, pp. 1005-1028.
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Aung, TH, Khabbaz, H & Fatahi, B 2016, 'Parametric Study of Applied Stresses on Infiltration Modular Cells Installed under Roads', Procedia Engineering, vol. 143, pp. 1325-1332.
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© 2016 The Authors. Published by Elsevier B.V. Modular geocellular units are applicable for the prevention and minimisation of stormwater runoff and flooding as a sustainable and cost-effective solution of road applications for drainage. The integrated units buried are exposed to the dead loads and live loads emerging from the surrounding soil pressure, pore water pressure and surcharge. Thus, a computer program using MATLAB is developed for the assessment of the total vertical and lateral earth pressure exerting on the modules complying with the Australian Standards AS 4678 (2002) and AS 5100.2(2004). Lateral earth pressure concept based on Rankine's theory is adopted in this model as the analytical approach. Closed-form solutions based on the fundamental soil mechanics are applied in the analytical calculation steps made. The model also considers different guidelines such as AASHTO LRFD Bridge Design Specifications (2010) for the stress distribution of vehicular loads according to the selected axle type. In consideration of the interaction of the moving vehicle and the bridge, the dynamic load allowance is also applied in terms of the static equivalent of the dynamic and vibratory effect as prescribed in AS 5100.2 (2004). Based on the results obtained, the numerical and theoretical results generated by the program provide considerable and influential factors in regarding to the parametric study and sensitivity analysis presented in this paper.

Aung, Y, Khabbaz, H & Fatahi, B 2016, 'Review on Thermo-mechanical Approach in the Modelling of Geo-materials Incorporating Non-associated Flow Rules', Procedia Engineering, vol. 143, pp. 331-338.
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© 2016 The Authors. Published by Elsevier B.V. Recently, there has been a burgeoning interest in developing constitutive soil models from the laws of thermodynamics, mainly due to the benefits that these models automatically obey them and the approach provides a well-established structure and reduces the need for 'ad hoc' postulates. A thermodynamic framework, also known as thermo-mechanical framework, has the capability to predict the behaviour of geotechnical materials, which requires the anticipated incorporation of non-associated flow rules. As it is very challenging to achieve acceptable accuracy in plasticity modelling of granular materials, this paper aims to review this framework not only to discuss the details of the major components but also to highlight the capability of generating non-associated flow rules in a natural way from thermo-mechanical principles. This approach introduces the use of internal variables to develop the two thermodynamic potentials (the free energy and the rate of dissipation functions), sufficient to derive the corresponding yield function, flow rule, isotropic and kinematic hardening rules as well as the basic elasticity law. It is shown that the non-associated flow rule can be derived naturally from the postulated stress-dependent dissipation increment function. Comparison has been made with stress-independent dissipation to demonstrate that the approach can also successfully explain the behaviour of standard materials with associated flow rules. The basic steps for the thermo-mechanical formulation for developing a constitutive model are also reviewed and summarised. Furthermore, the power of conventional mathematical technique, Legendre transformation, in the derivation of constitutive equations has been highlighted.

Azari, B, Fatahi, B & Khabbaz, H 2016, 'Assessment of the Elastic-Viscoplastic Behavior of Soft Soils Improved with Vertical Drains Capturing Reduced Shear Strength of a Disturbed Zone', International Journal of Geomechanics, vol. 16, no. 1, pp. B4014001-B4014001.
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© 2015 American Society of Civil Engineers. Soil disturbance induced by the installation of vertical drains reduces the horizontal soil permeability and shear strength in the disturbed zone. Thus, the soil disturbance contributes to the reduced overconsolidation ratio (OCR) of the soil in the vicinity of drains, influencing soil deformation. Although a significant amount of research has been conducted on the effect of permeability variations in the smear zone, the influence of the reduced shear strength in the smear zone on the ground behavior has not been investigated. In this study, a numerical solution adopting an elastic-viscoplastic model with nonlinear creep function in combination with the consolidation equations has been developed. Moreover, the effects of shear strength variation in the disturbed zone on the time-dependent behavior of soft soil deposits improved with vertical drains and preloading have been studied. The applied elastic-viscoplastic model is based on the framework of the modified Cam-clay model, capturing soil creep during excess pore-water pressure dissipation. Furthermore, nonlinear variations of the creep coefficient with stress and time as well as the permeability variations during the consolidation process are considered. The predicted results have been compared with available field measurements. According to the results, the OCR profile of the disturbed zone influences the viscoplastic strain rate, the creep strain limit, and consequently the soil deformation.

Basack, S, Indraratna, B & Rujikiatkamjorn, C 2016, 'Analysis of the Behaviour of Stone Column Stabilized Soft Ground Supporting Transport Infrastructure', Procedia Engineering, vol. 143, pp. 347-354.
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Basack, S, Indraratna, B & Rujikiatkamjorn, C 2016, 'Modeling the Performance of Stone Column–Reinforced Soft Ground under Static and Cyclic Loads', Journal of Geotechnical and Geoenvironmental Engineering, vol. 142, no. 2, pp. 04015067-04015067.
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Biabani, MM, Indraratna, B & Ngo, NT 2016, 'Modelling of geocell-reinforced subballast subjected to cyclic loading', Geotextiles and Geomembranes, vol. 44, no. 4, pp. 489-503.
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This paper presents the experimental and numerical studies of geocell-reinforced subballast subjected to cyclic loading. A series of laboratory experiments were conducted using a large-scale prismoidal triaxial apparatus that was subjected to relatively low confining pressures of σ'3 = 10-30 kPa and a frequency of f = 10 Hz. Numerical simulations were performed using the commercial finite element package ABAQUS in three dimensions to realistically model cellular confinement, and to study the effectiveness of geocell reinforcement on subballast. A cyclic loading with a periodic and positive full-sine waveform was adopted to model the geocell-reinforced subballast, which is similar to the load carried out in the laboratory. The results of numerical modelling agreed well with the experimental data, and showed that geocell could effectively decrease the lateral and axial deformations of the reinforced subballast. The numerical model was also validated by the field data, and the results were found to be in good agreement, indicating that the proposed model was able to capture the load-deformation behaviour of geocell-reinforced subballast under cyclic loading. A parametric study was also carried out to evaluate the effect of the subballast strength and geocell stiffness on the mobilized tensile strength in the geocell mattress. It was found that the maximum mobilized tensile stress occurs on the subballast with the lowest degree of stiffness. Also the results revealed that lateral displacement decreased further by increasing geocell stiffness, and geocell with a relatively low stiffness performs very well compared to the geocell with a higher stiffness.

Biabani, MM, Ngo, NT & Indraratna, B 2016, 'Performance evaluation of railway subballast stabilised with geocell based on pull-out testing', Geotextiles and Geomembranes, vol. 44, no. 4, pp. 579-591.
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A large-scale apparatus was designed and built at the University of Wollongong to evaluate the pull-out strength of rail subballast reinforced with geocells. A series of tests were carried out to investigate the pull-out resistance, mobilised tensile strength (τtensile) and passive strength (τpassive) of a subballast-geocell assembly under a given range of overburden pressure (1 kPa ≤ q ≤ 45 kPa). The interface was held in a vertical alignment to better simulate the interaction between subballast and geocell in accordance with routine track practices. The test results show that the geocell reinforcement provides a considerable degree of passive resistance, where the opening area (OA) and lateral pressure (σn) over the geocell strip are found to be influential factors. A three-dimensional finite element simulation was also conducted. The numerical results show that the tensile strength mobilised in the geocell will increase as the geocell stiffness increases, but causes a reduction in τpassive. A parametric study was also developed to investigate the impact of geocell stiffness and friction coefficient on the passive resistance and mobilised tensile strength. These results indicate that the passive resistance and mobilised tensile strength increase with the increase in overburden pressure (q) and friction coefficient (δ).

Burton, GJ, Pineda, JA, Sheng, D, Airey, DW & Zhang, F 2016, 'Exploring one-dimensional compression of compacted clay under constant degree of saturation paths', Géotechnique, vol. 66, no. 5, pp. 435-440.
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This note presents a novel approach for controlling the degree of saturation during one-dimensional compression of unsaturated soils. This technique offers a simple and versatile way to study the hydro-mechanical response of unsaturated soils as well as the unsaturated–saturated soil transition. By using a multi-stage approach, the same specimen can be used to evaluate the compressibility of unsaturated specimens at different degrees of saturation, which may reduce the long testing periods commonly required for unsaturated soil testing. The experimental results described in this paper show that the proposed technique is capable of controlling the degree of saturation within reasonable limits and provides an interesting approach to analyse the coupled hydraulic and mechanical behaviour of unsaturated soils.

Chan, B, Guan, H, Hou, L, Jo, J, Blumenstein, M & Wang, J 2016, 'Defining a conceptual framework for the integration of modelling and advanced imaging for improving the reliability and efficiency of bridge assessments', Journal of Civil Structural Health Monitoring, vol. 6, no. 4, pp. 703-714.
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© 2016, Springer-Verlag Berlin Heidelberg. Current bridge inspection practices are typically predicated upon manual paper-based data collection methods, which significantly limit the ability to transfer knowledge gained throughout the lifecycle of the asset, to benefit the assessment of the inspector or engineer. This study aims to overcome the limitations of current practices and proposes a conceptual framework to improve the reliability and efficiency of current bridge asset management practices through the integration of Building Information Modeling (BIM) and advanced computing and imaging technologies. As a tool for bridge inspections, BIM offers significant potential when integrated with laser scanning and keypoint-based texture recognition, which allows for the detection of such defects as cracking, corrosion or settlement in bridge components. In recent years, the construction industry has seen an increased use of BIM technology on-site to aid the construction process. However, the applications of it are deficient through the asset management phases of a project. Given the ability of BIM to house all component specific information gathered from the construction, inspection and maintenance phases, BIM is envisioned to allow emphasis to be placed on retrieving the relevant information throughout the project lifecycle, ultimately enabling engineers and bridge inspectors to make more informed decisions about the current condition of the structure. Using BIM as the focal point for information collection throughout the project lifecycle, findings from advanced imaging and data processing are proposed to be stored within the model for recall at future bridge assessments.

Chen, Q, Indraratna, B & Rujikiatkamjorn, C 2016, 'Behaviour of lignosulfonate-treated soil under cyclic loading', Proceedings of the Institution of Civil Engineers - Ground Improvement, vol. 169, no. 2, pp. 109-119.
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In this paper, the effectiveness of an environmentally-friendly stabilising agent for soil, lignosulfonate (LS), is examined through a series of cyclic triaxial tests. The deformation characteristics of the contents of LS-treated sandy silt when subjected to undrained cyclic triaxial loading are investigated at different confining pressures and cyclic stress levels. Test results indicate that under a given confining pressure and cyclic deviator stress, the rate of increase in axial strain is controlled by the addition of LS, which results in a smaller value of plastic axial strain (εa,p). For all the untreated and LS-treated specimens, the rate of increase in εa,p increases with the increasing cyclic stress ratio (CSR). A critical value of CSR exists for a given LS content (i.e. CSRCR), below which the specimens could remain stable irrespective of the number of load cycles. The longevity of treated specimens is improved significantly, especially for the specimens with LS = 2% by weight. As the treated specimens are subjected to a high level of cyclic stress, the excess pore pressure shows a decreasing trend with the increasing number of cycles, but then increases again rapidly when the failure becomes imminent. Compared with the untreated soil, the resilient modulus increases significantly as a result of LS treatment, especially for LS = 2%. When the LS > 2%, there is no additional advantage, implying that 2% LS treatment is an optimum for this soil.

Chen, Q, Indraratna, B, Carter, JP & Nimbalkar, S 2016, 'Isotropic–kinematic hardening model for coarse granular soils capturing particle breakage and cyclic loading under triaxial stress space', Canadian Geotechnical Journal, vol. 53, no. 4, pp. 646-658.
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In this paper, a simple but comprehensive cyclic stress–strain model that incorporates particle breakage for granular soils including ballast and rockfill has been proposed on the basis of bounding surface plasticity theory within a critical state framework. Particle breakage and its effects are captured by a critical state line that is translated in voids ratio–stress space according to the dissipated energy (plastic work), through a hyperbolic function. A comprehensive equation related to particle breakage is proposed for the stress–dilatancy relationship to capture the complex dilatancy of granular soils. By extending Masing’s rule to bounding surface plasticity theory and introducing a generalized homological centre, a combined isotropic–kinematic hardening rule and a mapping rule have been established to simulate more realistically the response of gravelly soils under cyclic loading. The applicability and accuracy of this model are demonstrated by comparing its predictions with experimental results for different types of granular soils, including rockfill, under both monotonic and cyclic loading conditions. This study shows that the model can capture the characteristic features of coarse granular soils under complex loading paths.

Cheng, S, Yu, L, Zhang, D, Huo, L & Ji, J 2016, 'Consensus of second-order multi-agent systems using partial agents' velocity measurements', NONLINEAR DYNAMICS, vol. 86, no. 3, pp. 1927-1935.
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Choudhary, K, Indraratna, B & Rujikiatkamjorn, C 2016, 'Pore pressure based method to quantify smear around a vertical drain', Géotechnique Letters, vol. 6, no. 3, pp. 211-215.
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Radial consolidation testing of Ballina clay (New South Wales, Australia) was carried out using a large-scale consolidometer 650 mm in diameter. In this study, the characteristics of the smear zone were evaluated on the basis of hydraulic gradient changes derived from the measured excess pore pressure data in the radial direction. The extent of the smear zone determined using this technique is compared with past approaches, where the variations in water content and lateral permeability were adopted to evaluate smear. The approach proposed herein based on the change of hydraulic gradient coincides with the previous two methods, and the smear zone could be established at almost 2·5 times the effective mandrel diameter. A good agreement is also found between the theoretical radial consolidation predictions, after incorporating the smear zone characteristics and the measured time–settlement curve. The proposed method for the determination of smear zone extent can be carried out during consolidation with minimum disturbance to soil, provided a sufficient number of pore pressure transducers are installed. It also eliminates the need for a number of soil samples and high-quality soil sampling technique after the installation of the drain.

Dackermann, U, Elsener, R, Li, J & Crews, K 2016, 'A comparative study of using static and ultrasonic material testing methods to determine the anisotropic material properties of wood', CONSTRUCTION AND BUILDING MATERIALS, vol. 102, no. 2, pp. 963-976.
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© 2015 Elsevier Ltd. This paper presents a comparative study using static and ultrasonic testing for the determination of the full set of orthotropic material properties of wood. In the literature, material properties are typically only available in the longitudinal direction, and most international standards do not provide details on the testing of the other two secondary directions (radial and tangential). This work provides a comprehensive study and discussions on the determination of all twelve orthotropic material properties of two hardwood species using static testing and an alternative testing approach based on ultrasonic waves. Recommendations are given on the execution of the tests and the interpretation and calibration of the results.

Dang, LC, Fatahi, B & Khabbaz, H 2016, 'Behaviour of Expansive Soils Stabilized with Hydrated Lime and Bagasse Fibres', ADVANCES IN TRANSPORTATION GEOTECHNICS III, vol. 143, pp. 658-665.
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© 2016 The Authors. Published by Elsevier B.V. Soil stabilization is the most common ground improvement technique adopted to improve problematic soil properties. This investigation exhibits a series of laboratory tests conducted to evaluate the influences of bagasse fibres and hydrated lime addition on the engineering properties and shrink-swell behaviour of stabilised expansive soils. Bagasse fibre is industrial waste by-product left after the crushing of sugar cane for juice extraction that was used in this study as reinforcing component for expansive soil stabilization. The expansive soils used in this investigation were collected from Queensland, Australia. In order to investigate the influences of bagasse fibres on the engineering behaviour of expansive soil, varying proportions of randomly distributed bagasse fibres of 0.5%, 1.0%, and 2.0% were added to expansive soil and hydrated lime-expansive soils mixed with different bagasse fibre proportions were also investigated. Although, an array of experimental tests have been undertaken on untreated and treated expansive soil samples, merely the outcomes of linear shrinkage, unconfined compressive strength (UCS) tests after various curing periods of 3, 7 and 28 days are presented in this paper. Other test results have been identified as follow up research. The findings of this experimental investigation indicate that bagasse fibre reinforcement blended with hydrated lime increased the compressive strength of expansive soil with increase in curing time and additives contents, whereas the linear shrinkage of stabilised expansive soils decreased with increasing hydrated lime and bagasse fibre proportions and curing periods. Based on the reasonable laboratory test results, it can be noted that the expansive soils can be successfully stabilized by combination of hydrated lime and bagasse fibres.

Dang, LC, Hasan, H, Fatahi, B, Jones, R & Khabbaz, H 2016, 'Enhancing the engineering properties of expansive soil using bagasse ash and hydrated lime', International Journal of GEOMATE, vol. 11, no. 3, pp. 2447-2454.
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The main objective of this paper is to investigate the influence of hydrated lime and bagasse ash on engineering properties of expansive soil obtained from an array of laboratory tests. Bagasse ash is a readily available waste by-product of the sugar-cane refining industry posing risks to environment. Bagasse ash is considered in this investigation in order to evaluate the potential benefits of its pozzolanic material for stabilisation of expansive soil. The preparation of stabilised soil specimens was conducted by changing the bagasse ash contents from 0 to 25% by dry weight of expansive soil along with an increase in hydrated lime. The bearing capacity and shrinkage properties of stabilised expansive soil were examined through a series of experimental tests including linear shrinkage and California bearing ratio (CBR) after various curing periods of 3, 7 and 28 days. The results reveal that the additions of hydrated lime and bagasse ash improved the strength and bearing capacity of stabilised expansive soil remarkably, and meanwhile significantly reduced the linear shrinkage of treated expansive soil. Hence, the application of hydrated lime and bagasse ash as reinforcing material can not only enhance the engineering properties of expansive soil, but also facilitate sustainable development by using sugarcane waste by-product to improve unusable clay material in road construction.

Das, A, Ferrer, MA, Pal, U, Pal, S, Diaz, M & Blumenstein, M 2016, 'Multi‐script versus single‐script scenarios in automatic off‐line signature verification', IET Biometrics, vol. 5, no. 4, pp. 305-313.
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Das, A, Pal, U, Ferrer, MA & Blumenstein, M 2016, 'A framework for liveness detection for direct attacks in the visible spectrum for multimodal ocular biometrics', Pattern Recognition Letters, vol. 82, no. 2, pp. 232-241.
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© 2015 Elsevier B.V. In this research a new framework for software-based liveness detection for direct attacks in multimodal ocular biometrics across the visible spectrum is proposed. The framework aims to develop a more realistic method for liveness detection compared to previous frameworks proposed in the literature. To fulfil the above highlighted aims in this framework, intra-class level (i.e. user level) liveness detection is introduced. To detect liveness, a new set of image quality-based features is proposed for multimodal ocular biometrics in the visible spectrum. A variety of transformed domain (focus related) aspect and contrast-related quality features are employed to design the framework. Furthermore a new database is developed for liveness detection of multimodal ocular biometrics, which has the prominent presence of multimodal ocular traits (both sclera and iris). Moreover this database is comprised of a larger variety of fake images; those were prepared by employing versatile forging techniques which can be exhibited by imposters. Therefore the proposed schema has dealt with versatile categories of spoofing methods, which were not considered previously in the literature. The database contains a set of 500 fake and 500 genuine eye images acquired from 50 different eyes. An appreciable liveness detection result is achieved in the experiments. Furthermore, the experimental results conclude that this new framework is more efficient and competitive when compared to previous liveness detection schemes.

Diez, A, Khoa, NLD, Makki Alamdari, M, Wang, Y, Chen, F & Runcie, P 2016, 'A clustering approach for structural health monitoring on bridges', Journal of Civil Structural Health Monitoring, vol. 6, no. 3, pp. 429-445.
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© 2016, Springer-Verlag Berlin Heidelberg. Structural health monitoring is a process for identifying damage in civil infrastructures using sensing system. It has been increasingly employed due to advances in sensing technologies and data analytic using machine learning. A common problem within this scenario is that limited data of real structural faults are available. Therefore, unsupervised and novelty detection machine learning methods must be employed. This work presents a clustering based approach to group substructures or joints with similar behaviour on bridge and then detect abnormal or damaged ones, as part of efforts in applying structural health monitoring to the Sydney Harbour Bridge, one of iconic structures in Australia. The approach is a combination of feature extraction, a nearest neighbor based outlier removal, followed by a clustering approach over both vibration events and joints representatives. Vibration signals caused by passing vehicles from different joints are then classified and damaged joints can be detected and located. The validity of the approach was demonstrated using real data collected from the Sydney Harbour Bridge. The clustering results showed correlations among similarly located joints in different bridge zones. Moreover, it also helped to detect a damaged joint and a joint with a faulty instrumented sensor, and thus demonstrated the feasibility of the proposed clustering based approach to complement existing damage detection strategies.

Ding, Y, Huang, W, Sheng, D & Sloan, SW 2016, 'Reply to discussion on “Numerical study on finite element implementation of hypoplastic models” by Yutang Ding, Wenxiong Huang, Daichao Sheng, and Scott W. Sloan [Comput. Geotech. 68 (2015) 78–90]', Computers and Geotechnics, vol. 71, pp. 278-280.
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Editorial Board of Landslides 2016, 'Editors and reviewers working for Landslides in 2015', Landslides, vol. 13, pp. 1585-1591.

Fanos, AM & Pradhan, B 2016, 'Multi-scenario Rockfall Hazard Assessment Using LiDAR Data and GIS', Geotechnical and Geological Engineering, vol. 34, no. 5, pp. 1375-1393.
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Fanos, AM, Pradhan, B, Aziz, AA, Jebur, MN & Park, H-J 2016, 'Assessment of multi-scenario rockfall hazard based on mechanical parameters using high-resolution airborne laser scanning data and GIS in a tropical area', Environmental Earth Sciences, vol. 75, no. 15, p. 1129.
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Ghosh, B, Fatahi, B & Khabbaz, H 2016, 'Mechanical Model to Analyse Multilayer Geosynthetic Reinforced Granular Layer in Column Supported Embankments', ADVANCES IN TRANSPORTATION GEOTECHNICS III, vol. 143, pp. 387-394.
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© 2016 The Authors. Published by Elsevier B.V. The objective of this paper is to develop a mechanical model to predict the behaviour of a multilayer geosynthetic reinforced granular fill soft soil system improved with controlled modulus columns beneath the embankment. Deformation of geosynthetics embedded granular layer due to bending and shear is considered in this study. Therefore, geosynthetic reinforced granular fill has been idealised as a reinforced Timoshenko beam while the columns and the soft soil have been idealised as a layer of linear springs with varied stiffness. Plane strain conditions are considered for the loading and reinforced foundation soil system. Tension developed in the geosynthetics, rotation and settlements of the improved soft ground are predicted using the proposed model. This study shows the effects of multilayer geosynthetics on the settlement response of the granular layer. A notable reduction of the settlement has been observed as a result of the using multilayer weaker geosynthetic reinforcement system when compare to one stronger geosynthetics layer. It is also observed that the top reinforcement layer is subjected to maximum mobilised tension at the column edge whereas bottom reinforcement layer is more effective in controlling the deflection in the middle of two columns.

Gu, X, Li, J, Li, Y & Askari, M 2016, 'Frequency control of smart base isolation system employing a novel adaptive magneto-rheological elastomer base isolator', Journal of Intelligent Material Systems and Structures, vol. 27, no. 7, pp. 849-858.
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In the past decades, base isolation techniques have become increasingly popular for seismic protection of civil structures owing to its capability of decoupling buildings from harmful ground motion. However, it has been recognised recently that the traditional passive base isolation technique could encounter a serious problem during earthquakes due its incapability in adjusting the isolation frequency to cope with the unpredictability and diversity of earthquakes. To address this challenge, a great deal of research efforts have been conducted to improve traditional base isolation systems, most of which focused on hybrid supplementary devices (passive, active and semi-active types) for the isolators to control displacement or to dissipate seismic energy. On the other hand, the most effective approach to address the aforementioned challenge should lay on varying isolator stiffness in real-time to achieve real-time spontaneous decoupling. A recent advance of the development of an adaptive magneto-rheological elastomer base isolator has brought such idea to reality as the new magneto-rheological elastomer base isolator is capable to alter its stiffness significantly in real-time. In this article, an innovative smart base isolation system employing such magneto-rheological elastomer isolator is proposed and a novel frequency control algorithm is developed to shift the fundamental frequency of the structure away from the dominant frequency range of earthquakes. Such design enables the building to avoid resonant state in real-time according to the on-coming spectrum of the earthquakes. Extensive simulation has been conducted using a five-storey benchmark model with the isolation system, and testing results indicate that the proposed control system is able to significantly suppress both the floor accelerations and inter-storey drifts simultaneously under different earthquakes.

Gu, X, Yu, Y, Li, J, Li, Y & Alamdari, MM 2016, 'Semi-active storey isolation system employing MRE isolator with parameter identification based on NSGA-II with DCD', Earthquakes and Structures, vol. 11, no. 6, pp. 1101-1121.
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© 2016 Techno-Press, Ltd. Base isolation, one of the popular seismic protection approaches proven to be effective in practical applications, has been widely applied worldwide during the past few decades. As the techniques mature, it has been recognised that, the biggest issue faced in base isolation technique is the challenge of great base displacement demand, which leads to the potential of overturning of the structure, instability and permanent damage of the isolators. Meanwhile, drain, ventilation and regular maintenance at the base isolation level are quite difficult and rather time- and fund- consuming, especially in the highly populated areas. To address these challenges, a number of efforts have been dedicated to propose new isolation systems, including segmental building, additional storey isolation (ASI) and mid-storey isolation system, etc. However, such techniques have their own flaws, among which whipping effect is the most obvious one. Moreover, due to their inherent passive nature, all these techniques, including traditional base isolation system, show incapability to cope with the unpredictable and diverse nature of earthquakes. The solution for the aforementioned challenge is to develop an innovative vibration isolation system to realise variable structural stiffness to maximise the adaptability and controllability of the system. Recently, advances on the development of an adaptive magneto-rheological elastomer (MRE) vibration isolator has enlightened the development of adaptive base isolation systems due to its ability to alter stiffness by changing applied electrical current. In this study, an innovative semi-active storey isolation system inserting such novel MRE isolators between each floor is proposed. The stiffness of each level in the proposed isolation system can thus be changed according to characteristics of the MRE isolators. Nondominated sorting genetic algorithm type II (NSGA-II) with dynamic crowding distance (DCD) is utili...

Hagelstein, B, Abolhasan, M, Franklin, D, Safaei, F & Ni, W 2016, 'Analytic Performance Model for State-Based MAC Layer Cooperative Retransmission Protocols', IEEE TRANSACTIONS ON MOBILE COMPUTING, vol. 15, no. 1, pp. 32-44.
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© 2015 IEEE. Cooperative retransmission can significantly improve link reliability over lossy and time-varying wireless links. However, comparing retransmission protocols is challenging, and generally requires simplistic assumptions specific to each protocol. In this paper, we develop a general model to evaluate cooperative retransmission protocols with distributed, slot-based contention algorithms. Specifically, we propose to calculate the relay time-out probabilities at a MAC time-slot scale, formulate retransmission outcomes as functions of the time-out probabilities, and derive the probability of a retransmission process for every data frame. We also propose a Markov extension of our model to characterise the dependency between retransmissions of multiple frames. This enables our model to analyse continuous retransmissions of successive frames. Validated by QualNet simulations, our model can analytically predict the probabilities of cooperative retransmissions with an accuracy of ± 1%. As a result, direct comparisons between cooperative retransmission protocols become tangible, without implementing the full protocol in a state-based simulator.

Hasan, H, Dang, L, Khabbaz, H, Fatahi, B & Terzaghi, S 2016, 'Remediation of Expansive Soils Using Agricultural Waste Bagasse Ash', Procedia Engineering, vol. 143, pp. 1368-1375.
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© 2016 The Authors. Published by Elsevier B.V. Bagasse is a fibrous material remaining after crushing sugarcane to extract its juice; and bagasse ash is produced after burning bagasse. Improper disposal of this material can create environmental problems around sugar manufacturing plants. Bagasse ash, comprising a high percentage of silica (SiO2), is considered as a sensible pozzolanic material with non-reactive behaviour and has potential to be used in road subgrade stabilisation. One of the main challenges for transportation organisations in Australia is to treat subgrades including expansive soils. Expansive soils exhibit significant movements when the moisture content changes, and hence it causes substantial damage to road pavements constructed over these type of soils. Road engineers need to employ materials having acceptable strength, relatively low price and being eco-friendly. In order to demonstrate the potential ability of bagasse ash in curtailing the adverse effects of expansive soils on roads, an array of experimental tests using bagasse ash have been conducted. In this study to activate and improve the effectiveness of bagasse ash, hydrated lime was used and mixed with black soil samples, collected from Queensland Australia. Samples were prepared using different contents of bagasse ash and hydrated lime (0%, 6%, 10%, 18% and 25% by the dry mass of soil), at a ratio of 3:1, respectively. The results of free swell ratio (FSR) test, unconfined compression strength (UCS) and California bearing ratio (CBR) tests are presented for untreated and treated samples after various curing time periods of 3, 7 and 28 days. The outcomes of these tests clearly demonstrate that stabilisation of expansive soils using bagasse ash and hydrated lime not only improves the strength, but also facilitates to cope with environmental concerns through reduction of sugar industry waste material.

Heitor, A, Indraratna, B & Rujikiatkamjorn, C 2016, 'Small Strain Behaviour of a Compacted Subgrade Soil', Procedia Engineering, vol. 143, pp. 260-267.
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Heitor, A, Indraratna, B, Kaliboullah, CI, Rujikiatkamjorn, C & McIntosh, GW 2016, 'Drained and Undrained Shear Behavior of Compacted Coal Wash', Journal of Geotechnical and Geoenvironmental Engineering, vol. 142, no. 5, pp. 04016006-04016006.
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Ho, L & Fatahi, B 2016, 'One-Dimensional Consolidation Analysis of Unsaturated Soils Subjected to Time-Dependent Loading', International Journal of Geomechanics, vol. 16, no. 2, pp. 04015052-04015052.
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Ho, L, Fatahi, B & Khabbaz, H 2016, 'Analytical solution to axisymmetric consolidation in unsaturated soils with linearly depth-dependent initial conditions', Computers and Geotechnics, vol. 74, pp. 102-121.
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© 2016. This paper introduces an analytical solution for the axisymmetric consolidation of unsaturated soils subjected to constant external loading. The analytical procedure employs variables separation and Laplace transformation techniques while capturing the uniform and linear initial excess pore pressure distributions with depth. Excess pore-air and pore-water pressures as functions of time, radial and vertical flows are determined using Laplace transforms, Fourier Bessel and sine series, respectively. In this study, the consolidation behavior, in terms of changes in excess pore-air and pore-water pressures and the average degree of consolidation, are investigated against the air to water permeability ratio. The effects of radial distance from the drain well on the dissipation rate are likewise highlighted in worked examples. Excess pore pressure isochrones and the matric suction varying with time are also presented.

Hokmabadi, AS & Fatahi, B 2016, 'Influence of Foundation Type on Seismic Performance of Buildings Considering Soil-Structure Interaction', INTERNATIONAL JOURNAL OF STRUCTURAL STABILITY AND DYNAMICS, vol. 16, no. 8, pp. 1-29.
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© 2016 World Scientific Publishing Company. In selecting the type of foundation best suited for mid-rise buildings in high risk seismic zones, design engineers may consider that a shallow foundation, a pile foundation, or a pile-raft foundation can best carry the static and dynamic loads. However, different types of foundations behave differently during earthquakes, depending on the soil-structure interaction (SSI) where the properties of the in situ soil and type of foundation change the dynamic characteristics (natural frequency and damping) of the soil-foundation-structure system. In order to investigate the different characteristics of SSI and its influence on the seismic response of building frames, a 3D numerical model of a 15-storey full-scale (prototype) structure was simulated with four different types of foundations: (i) A fixed-based structure that excludes the SSI, (ii) a structure supported by a shallow foundation, (iii) a structure supported by a pile-raft foundation in soft soil and (iv) a structure supported by a floating (frictional) pile foundation in soft soil. Finite difference analyzes with FLAC3D were then conducted using real earthquake records that incorporated material (soil and superstructure) and geometric (uplifting, gapping and P-Δ effects) nonlinearities. The 3D numerical modeling procedure had previously been verified against experimental shaking table tests conducted by the authors. The results are then presented and compared in terms of soil amplification, shear force distribution and rocking of the superstructure, including its lateral deformation and drift. The results showed that the type of foundation is a major contributor to the seismic response of buildings with SSI and should therefore be given careful consideration in order to ensure a safe and cost effective design.

Hong, H, Naghibi, SA, Pourghasemi, HR & Pradhan, B 2016, 'GIS-based landslide spatial modeling in Ganzhou City, China', Arabian Journal of Geosciences, vol. 9, no. 2, p. 112.
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Hong, H, Pradhan, B, Jebur, MN, Bui, DT, Xu, C & Akgun, A 2016, 'Spatial prediction of landslide hazard at the Luxi area (China) using support vector machines', Environmental Earth Sciences, vol. 75, no. 1, p. 40.
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Hussaini, SKK, Indraratna, B & Vinod, JS 2016, 'A laboratory investigation to assess the functioning of railway ballast with and without geogrids', Transportation Geotechnics, vol. 6, pp. 45-54.
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Idrees, M & Pradhan, B 2016, 'Hybrid Taguchi-Objective Function optimization approach for automatic cave bird detection from terrestrial laser scanning intensity image', International Journal of Speleology, vol. 45, no. 3, pp. 289-301.
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This paper proposes an optimized Taguchi-objective function segmentation-based image analysis to detect bird nests in a cave from high resolution terrestrial laser scanning intensity images. First, the Taguchi orthogonal array was used to design 25 experiments with three segmentation parameters: scale, shape, and compactness, each having five variable factor levels. Then, a plateau objective function was computed for each experiment using their respective level combinations. A merger of the factor level combination in the orthogonal array and the computed plateau objective function values was used to generate main effects and interaction plots for signal-to-noise ratios, which provided a measure of robustness for scale, shape, and compactness factors. The optimized parameters were used in the segmentation process in eCognition. The image object was then classified into nest and cave-wall on the basis of laser return intensity and area index using knowledge-based rule sets, and the detection accuracy was evaluated. The result produced area under ROC curve of 0.93 with P<0.0001 at 95% confidence level. This indicates that the proposed method is effective for distinguishing birds from cave-wall with high precision. The classification result was transferred to ArcGIS where the detected nests were counted after post-classification editing. A total number of 25,959 nests were counted from the seven scan scenes used. This shows that the fusion of Taguchi and objective function is indeed an effective method to determine optimal segmentation parameters to group image objects as small as birds within a segment. Moreover, the use of segments’ spectral intensity value and area index increased classification accuracy significantly. Further, the method was tested for reliability using six additional images. The test of heterogeneity using Cochran’s Q and Inconsistency tests produced a P value of 0.384 and I2 value of 5.10% at 95% confidence interval, respectively. Th...

Idrees, MO, Pradhan, B, Buchroithner, MF, Shafri, HZM & Khairunniza Bejo, S 2016, 'Assessing the transferability of a hybrid Taguchi-objective function method to optimize image segmentation for detecting and counting cave roosting birds using terrestrial laser scanning data', Journal of Applied Remote Sensing, vol. 10, no. 3, pp. 035023-035023.
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Indraratna, B 2016, '1st Proctor Lecture of ISSMGE:', Transportation Geotechnics, vol. 7, pp. 74-114.
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Indraratna, B, Israr, J & Rujikiatkamjorn, C 2016, 'Closure to “Geometrical Method for Evaluating the Internal Instability of Granular Filters Based on Constriction Size Distribution” by Buddhima Indraratna, Jahanzaib Israr, and Cholachat Rujikiatkamjorn', Journal of Geotechnical and Geoenvironmental Engineering, vol. 142, no. 9, pp. 07016022-07016022.
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Indraratna, B, Kan, ME, Potts, D, Rujikiatkamjorn, C & Sloan, SW 2016, 'Analytical solution and numerical simulation of vacuum consolidation by vertical drains beneath circular embankments', Computers and Geotechnics, vol. 80, pp. 83-96.
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Indraratna, B, Nguyen, TT, Carter, J & Rujikiatkamjorn, C 2016, 'Influence of biodegradable natural fibre drains on the radial consolidation of soft soil', Computers and Geotechnics, vol. 78, pp. 171-180.
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Natural prefabricated vertical drains (NPVDs) produced from biodegradable materials such as jute and coir have some distinct advantages over conventional polymeric prefabricated vertical drains (CPVDs). For instance, NPVDs are not only able to discharge excess pore pressure effectively but are also beneficial to the environment thanks to their biodegradability. However, due to the biodegradability of the natural fibres, NPVDs can sometimes deteriorate too quickly in an adverse environment such as in highly acidic clay, which hampers the dissipation of excess pore pressure. In this paper, an analytical solution for radial consolidation that considers the time-dependent decay of drain discharge capacity is therefore proposed. The solution is applied to an exponential form of reduction of the drain discharge capacity, and then verified with the experimental results obtained in previous studies. The effect of drain degradation on soil consolidation is simulated using a finite element method (ABAQUS) and these numerical results are then compared to those obtained from the analytical approach. In addition, a new and flexible method using a matching factor to convert the parameters from axisymmetric to plane strain models is introduced and applied to radial consolidation. The modelling outcomes indicate a significant retardation of excess pore pressure dissipation due to drain degradation and this suggests the need to exercise caution when using biodegradable NPVDs.

Indraratna, B, Sun, Y & Nimbalkar, S 2016, 'Laboratory Assessment of the Role of Particle Size Distribution on the Deformation and Degradation of Ballast under Cyclic Loading', Journal of Geotechnical and Geoenvironmental Engineering, vol. 142, no. 7, pp. 04016016-04016016.
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© 2016 American Society of Civil Engineers. The deformation and degradation of ballast is influenced by the size of the aggregates. In this study, a series of cyclic drained triaxial tests was conducted on ballast with different sizes using the large-scale cylindrical triaxial apparatus designed and built at the University of Wollongong, and two different frequencies of cyclic loading were used to simulate low-speed and high-speed trains. From the laboratory results, coarse particles experience less vertical and lateral strains, whereas the volumetric strains decrease and then increase as the coefficient of uniformity increases, regardless of the loading frequency. Resistance to deformation and degradation is found to be improved by increasing ballast density. Different trends between the extent of breakage and particle size are observed for different breakage indices, and accordingly the extent of breakage is characterized into two distinct zones, depending on the coefficient of uniformity (Cu), where the significantly reduced breakage corresponds to a value of Cu larger than 1.8. The variation of particle shape before and after test is also quantified. A new particle size distribution that incorporates the size characteristics is proposed, as a result of this study.

Indraratna, B, Zhong, R & Rujikiatkamjorn, C 2016, 'An Analytical Model of PVD-assisted Soft Ground Consolidation', Procedia Engineering, vol. 143, pp. 1376-1383.
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Israr, J, Indraratna, B & Rujikiatkamjorn, C 2016, 'Laboratory Investigation of the Seepage Induced Response of Granular Soils Under Static and Cyclic Loading', Geotechnical Testing Journal, vol. 39, no. 5, pp. 20150288-20150288.
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Jaber, HS, Mansor, S, Pradhan, B & Ahmad, N 2016, 'Evaluation of SEBAL model for Evapotranspiration mapping in Iraq using remote sensing and GIS', International Journal of Applied Engineering Research, vol. 11, no. 6, pp. 3950-3955.
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Evapotranspiration is one of the major parameter in the hydrologic cycle. Standard measurements of this parameter is quite complex due to various factors such as variation of precipitation amount, spatial variation by latitude and longitude and changes in environment and specific site conditions. Although of this complexity, various methods were developed to estimate actual and potential Evapotranspiration such as Surface Energy Balance Algorithm for Land (SEBAL) method. SEBAL model calculates heat latent flux mostly from remotely sensed data. This paper aims to evaluate the SEBAL model for actual Evapotranspiration estimation in Al-babil city in Iraq using a SEBAL toolbox developed for ArcGIS software. The toolbox was evaluated with two reference actual Evapotranspiration datasets from Al-babil metrological stations. Overall accuracy of (R2 = 0.86) for the first dataset on March and (R2 = 0.85) for the second dataset on September were achieved. The result of this research indicates that the SEBAL model is effective for estimating actual Evapotranspiration in the studied area.

Jangid, J, Bera, AK, Joseph, M, Singh, V, Singh, TP, Pradhan, BK & Das, S 2016, 'Potential zones identification for harvesting wind energy resources in desert region of India – A multi criteria evaluation approach using remote sensing and GIS', Renewable and Sustainable Energy Reviews, vol. 65, pp. 1-10.
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Renewable energy is considered to be one of the viable options in consideration of intense economic development and increasing energy consumption. With maturity of advanced technologies, economical viable and environmental friendly, wind energy has become one of the fastest growing sources of renewable energy in the world. This study focuses on the combined use of geographic information systems (GIS) and spatial multi-criteria decision analysis for selecting the most appropriate sites for wind-farm development projects. This paper utilized wind speed data over a period of almost 20 years between 1991 and 2010 from different stations to assess the wind power potential sites. The wind energy potential zones were grouped into four categories as “high suitable”, “moderate suitable”, “low suitable” and “not suitable”. The results show that the study area has 12.20% (2787.78 km2) as high suitable, 17.06% (3899.78 km2) as moderate suitable and 11.06% (2528.61 km2) as low suitable. The most potential suitable sites were located in the northwestern (along Osian, Shergargh, Dechu, and Shaitrawa, Phalodi) of Jodhpur district, India. This scientific approach will enable resource managers during planning process to make informed decisions.

Jian, S, Hossein Rashidi, T, Wijayaratna, KP & Dixit, VV 2016, 'A Spatial Hazard-Based analysis for modelling vehicle selection in station-based carsharing systems', Transportation Research Part C: Emerging Technologies, vol. 72, pp. 130-142.
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Carsharing, as an alternative to private vehicle ownership, has spread worldwide in recent years due to its potential of reducing congestion, improving auto utilization rate and limiting the environmental impact of emissions release. To determine the most efficient allocation of resources within a carsharing program, it is critical to understand what factors affect the users’ behavior when selecting vehicles. This study attempts to investigate the importance of users’ attributes and fleet characteristics on choice set formation behavior in selecting vehicles using a Spatial Hazard Based Model (SHBM). In the SHBM model, “distance to a vehicle” is considered as the prospective decision criteria that carsharing users follow when evaluating the set of alternative vehicles. This variable is analogous to the duration in a conventional hazard-based model. In addition, user socio-demographic attributes, vehicle characteristics, land use type of the trip origin, etc., collected from the Australian carsharing company GoGet are utilized to parameterize the shape/scale/location parameter of the hazard function. A number of forms of parametric SHBMs are tested to determine the best fit to the data. The accelerated failure time model with a Log-logistic distribution was found to provide the best fit. The estimation results of the coefficients of the parameters can provide a starting point for carsharing organizations to optimize their pod locations and types of cars available at different pods to maximize usage.

Jiang, YB, He, N, Zhou, YZ, Xu, BH & Lin, ZQ 2016, 'Concept and measuring technique of groundwater level in vacuum preloading', Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering, vol. 38, no. 10, pp. 1917-1922.
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Nowadays there are controversial viewpoints on variation rules of groundwater level in vacuum preloading technique due to insufficient analysis of concepts and shortcomings of measuring techniques. In this study, based on the status of the water in soil, the potential energy condition of the groundwater level and the reference datum, the groundwater level in vacuum preloading is redefined as the absolute elevation of a surface where the gravity field hydraulic pressure component of the gravity water in the soil is zero. In addition, two basic conditions, which are required to meet the accuracy criteria of groundwater level measurements in vacuum preloading, are proposed. Then, the water lifting function in filter pipe section and the confining effect in impermeable pipe section, which are two negative effects of the existing measuring techniques of groundwater level affected by the distribution of the filter pipe, are analyzed. Consequently, a sectional type buoy groundwater measuring technique is put forward, including the full outer filter tube installed in the foundation and the built-in partition sectional type buoy water level indicator with the special rubber concave-convex partition. It is a method which can keep sealing while measuring, overcoming the negative effects of the distribution of the filter pipe. This proposed technique is theoretically suitable for measuring groundwater level under negative pressure and sealing membrane in vacuum preloading practice.

Kalhori, H, Ye, L, Mustapha, S, Li, J & Li, B 2016, 'Reconstruction and Analysis of Impact Forces on a Steel-Beam-Reinforced Concrete Deck', Experimental Mechanics, vol. 56, no. 9, pp. 1547-1558.
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Keshavarzi, A, Omran, E-SE, Bateni, SM, Pradhan, B, Vasu, D & Bagherzadeh, A 2016, 'Modeling of available soil phosphorus (ASP) using multi-objective group method of data handling', Modeling Earth Systems and Environment, vol. 2, no. 3, p. 157.
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The accurate estimation of available soil phosphorus (ASP) is required for the effective management of environmental resources and improving agricultural productivity. Direct measurement of ASP at large scales is time-consuming and expensive. Therefore, many empirical models or pedotransfer functions (PTFs) have been developed to obtain ASP. This study introduces a new model that estimates ASP from easily measurable soil properties by using the multi-objective group method of data handling (mGMDH) approach. Organic carbon, clay content, calcium carbonate equivalent, pH and ASP were obtained from 100 soil samples, which were collected by the stratified random sampling strategy in Mashhad Plain, Khorasan-e-Razavi Province, Northeast Iran. The suggested model for the prediction of ASP generated satisfactory results in terms of the statistical performance criteria. The coefficient of determination (R2) and mean square error (MSE) values of the mGMDH model in training step were 0.606 and 4.9671 mg kg−1, respectively, whereas those were 0.504 and 5.6685 mg kg−1, in the testing step. It was concluded that only 50 % of variations of ASP could be described by selecting easy-to-measure soil variables and owing to the key role of phosphorus in soil fertility and precision agriculture, the other related factors such as terrain attributes and fertilizer management should also be considered as they influence the distribution of the soil phosphorus.

Khabbaz, H & Fatahi, B 2016, 'Environmental geotechnics challenges in Australia', Environmental Geotechnics, vol. 3, no. 1, pp. 2-3.
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Khare, V, Shivakumara, P, Raveendran, P & Blumenstein, M 2016, 'A blind deconvolution model for scene text detection and recognition in video', Pattern Recognition, vol. 54, pp. 128-148.
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© 2016 Elsevier Ltd. Text detection and recognition in poor quality video is a challenging problem due to unpredictable blur and distortion effects caused by camera and text movements. This affects the overall performance of the text detection and recognition methods. This paper presents a combined quality metric for estimating the degree of blur in the video/image. Then the proposed method introduces a blind deconvolution model that enhances the edge intensity by suppressing blurred pixels. The proposed deblurring model is compared with other state-of-the-art models to demonstrate its superiority. In addition, to validate the usefulness and the effectiveness of the proposed model, we conducted text detection and recognition experiments on blurred images classified by the proposed model from standard video databases, namely, ICDAR 2013, ICDAR 2015, YVT and then standard natural scene image databases, namely, ICDAR 2013, SVT, MSER. Text detection and recognition results on both blurred and deblurred video/images illustrate that the proposed model improves the performance significantly.

Khezri, N, Mohamad, H & Fatahi, B 2016, 'Stability assessment of tunnel face in a layered soil using upper bound theorem of limit analysis', Geomechanics and Engineering, vol. 11, no. 4, pp. 471-492.
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Underground tunnelling is one of the sustainable construction methods which can facilitate the increasing passenger transportation in the urban areas and benefit the community in the long term. Tunnelling in various ground conditions requires careful consideration of the stability factor. This paper investigates three dimensional stability of a shallow circular tunnel in a layered soil. Upper bound theorem of limit analysis was utilised to solve the tunnel face stability problem. A three dimensional kinematic admissible failure mechanism was improved to model a layered soil and limiting assumptions of the previous studies were resolved. The study includes calculation of the minimum support pressure acting on the face of the excavation in closed-face excavations. The effects of the characteristics of the layers on the minimum support pressure were examined. It was found that the ratio of the thickness of cover layers particularly when a weak layer is overlying a stronger layer, has the most significant influence on the minimum tunnel support pressure. Comparisons have been made with the results of the numerical modelling using FLAC3D software. Results of the current study were in a remarkable agreement with those of numerical modelling.

Le, TM & Fatahi, B 2016, 'Trust-region reflective optimisation to obtain soil visco-plastic properties', Engineering Computations, vol. 33, no. 2, pp. 410-442.
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Purpose A non-linear creep function embedded in an elastic visco-plastic (EVP) model can simulate the decrease of creep compression rate with time. It overcomes the limitation of a linear logarithmic creep function, by which creep continuously increases to infinite value as time approaches infinity. However, the determination of the creep model parameters is a challenging task to apply the EVP model. Therefore, this paper presents a new numerical solution to determine the EVP model parameters applying trust-region reflective least square optimisation algorithm and the finite difference scheme to simulate stress-strain behaviour of soft soil. Design/methodology/approach In this paper, the developed method is verified against the field case study of Väsby test fill. A set of EVP model parameters is obtained by applying the developed method to the available laboratory consolidation results of Väsby clay. Then, the predictions of settlement and the excess pore water pressure at different depths are compared to the available field measurement. Findings The analysis results show the developed method is a reliable tool to evaluate the long-term performance of soft soils under embankments. Practical implications Practicing engineers can use the proposed optimisation algorithm to increase the accuracy of the soil visco-plastic model parameters by utilising all laboratory results of several loading stages during and after the...

Li, Q, Ling, X & Sheng, D 2016, 'Elasto-plastic behaviour of frozen soil subjected to long-term low-level repeated loading, Part I: Experimental investigation', Cold Regions Science and Technology, vol. 125, pp. 138-151.
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Li, Q, Ling, X & Sheng, D 2016, 'Elasto-plastic behaviour of frozen soil subjected to long-term low-level repeated loading, Part II: Constitutive modelling', Cold Regions Science and Technology, vol. 122, pp. 58-70.
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Liu, J, Ji, J & Zhou, J 2016, 'Synchronization of networked multibody systems using fundamental equation of mechanics', APPLIED MATHEMATICS AND MECHANICS-ENGLISH EDITION, vol. 37, no. 5, pp. 555-572.
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© 2016, Shanghai University and Springer-Verlag Berlin Heidelberg. From the analytical dynamics point of view, this paper develops an optimal control framework to synchronize networked multibody systems using the fundamental equation of mechanics. A novel robust control law derived from the framework is then used to achieve complete synchronization of networked identical or non-identical multibody systems formulated with Lagrangian dynamics. A distinctive feature of the developed control strategy is the introduction of network structures into the control requirement. The control law consists of two components, the first describing the architecture of the network and the second denoting an active feedback control strategy. A corresponding stability analysis is performed by the algebraic graph theory. A representative network composed of ten identical or non-identical gyroscopes is used as an illustrative example. Numerical simulation of the systems with three kinds of network structures, including global coupling, nearest-neighbour, and small-world networks, is given to demonstrate effectiveness of the proposed control methodology.

Liu, Y, Wang, Y, Sowmya, A & Chen, F 2016, 'Soft Hough Forest-ERTs: Generalized Hough Transform based object detection from soft-labelled training data', Pattern Recognition, vol. 60, pp. 145-156.
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Classical supervised object detection methods learn object models from labelled training data. This is tedious to create especially when the training dataset is large. Detection methods such as background subtraction and headlight detection can detect potential positive blobs that may contain the object without labelled training data. However, such blobs are not always accurate. They may include noise such as part of an object, multiple objects and other types of objects. Therefore, soft labels that indicate their probability of being positive may be more useful. A modified soft label estimation method based on Maximum Mean Discrepancy is introduced in this work. Based on it, a Generalized Hough Transform based object detection method from soft-labelled training data is proposed to utilize potential detections and their estimated soft labels. Experimental results show that the method can achieve comparable performance to supervised methods. It outperforms both Generalized Hough Transform based object detection with hard-labelled training blobs, and a state-of-the-art weakly supervised method.

Lloret‐Cabot, M, Sloan, SW, Sheng, D & Abbo, AJ 2016, 'Error behaviour in explicit integration algorithms with automatic substepping', International Journal for Numerical Methods in Engineering, vol. 108, no. 9, pp. 1030-1053.
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SummaryThis paper studies the behaviour of the error incurred when numerically integrating the elasto‐plastic mechanical relationships of a constitutive model for soils using an explicit substepping formulation with automatic error control. The correct update of all the variables involved in the numerical integration of the incremental stress–strain relationships is central to the computational performance of the integration scheme, and, although often missed in the literature, all variables (including specific volume) should be explicitly considered in the algorithmic formulation. This is demonstrated in the paper by studying, in the context of the Cam clay formulations for saturated soils, the influence that the updating of the specific volume has on the accuracy of the numerical solution. The fact that the variation of the local error with the size of the integrated strain depends on the order of local accuracy of the numerical method is also used in the paper to propose a simple and powerful strategy to verify the correctness of the implemented mathematical formulation. Copyright © 2016 John Wiley & Sons, Ltd.

Lu, M, Sloan, SW, Indraratna, B, Jing, H & Xie, K 2016, 'A new analytical model for consolidation with multiple vertical drains', International Journal for Numerical and Analytical Methods in Geomechanics, vol. 40, no. 11, pp. 1623-1640.
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SummaryVarious analytical theories of consolidation for soils with vertical drains have been proposed in the past. Most conventional theories are based on a cylindrical unit cell that contains only a single vertical drain. This paper described a new analytical model where a vertical drain located at the centre (the ‘inner vertical drain’) and is surrounded by two or three vertical drains (the ‘outer vertical drains’), the number of which depends on whether the configuration is triangular or rectangular. Both types of drains are combined into a cylindrical unit cell, and the water is assumed to flow both inwards to the inner vertical drain and outwards to the outer vertical drains distributed around the circumference. The outer radial boundary of the unit cell is regarded as a permeable boundary, with a drainage capacity of two or three separate vertical drains for triangular and rectangular configurations, respectively. The smear effects and the drainage resistances for both the inner and outer vertical drains are considered in the analysis as well. In this way, the equations governing the consolidation process with multiple vertical drains are derived, and the corresponding analytical solutions are obtained for instantaneously loading, ramp loading and multi‐stage of instantaneously loading and multi‐stage of ramp loading. The present solutions are finally compared with several conventional solutions for a single vertical drain in the literature. The results show that the present model predicts the same average degree of consolidation as conventional models do, which verifies the correctness of this new model. Finally, the settlement predicted by the present solution is compared with the measured settlement from a field test at the Port of Brisbane, Australia, which shows a good agreement between them. Copyright © 2016 John Wiley & Sons, Ltd.

Lu, X, Zhou, M, Ammari, AC & Ji, J 2016, 'Hybrid Petri Nets for Modeling and Analysis of Microgrid Systems', IEEE-CAA JOURNAL OF AUTOMATICA SINICA, vol. 3, no. 4, pp. 349-356.

Mahdavi, H, Fatahi, B, Khabbaz, H, Vincent, P & Kelly, R 2016, 'Comparison of Coupled Flow-deformation and Drained Analyses for Road Embankments on CMC Improved Ground', Procedia Engineering, vol. 143, pp. 462-469.
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© 2016 The Authors. Published by Elsevier B.V. The use of controlled modulus columns (CMC) is gaining increased popularity in the support of rail and road bridge approach embankments on soft soils. The further columns are driven into the competent firm soils, the further the design will rely on the inclusions to take the bulk of the vertical loads, as they become rigid inclusions. The advantage of this design approach is that it produces increased control over the settlement, but as a result the columns will attract greater loads, including bending moment and shear force in situations where non-uniform loading or ground conditions exist. The load on the composite soil-CMC is uniformly distributed by the upper layer of granular load transfer platform (LTP), which also includes a layer of reinforcement. Finite difference program FLAC3D has been used to numerically simulate an embankment on the improved ground with end-bearing CMC. A geosynthetic reinforcement layer has been simulated using the inbuilt FLAC3D geogrid element. In this paper, a comparison has been made between the drained and coupled flow-deformation analyses. The force in the reinforcement layer, in particular, has been compared for the two analysis approaches. It was found that according to the numerical simulation, the drained analysis provides lower estimates of the settlement, lateral displacement; and therefore, predicts less tension in the geosynthetic layer.

Makki Alamdari, M, Samali, B, Li, J, Kalhori, H & Mustapha, S 2016, 'Spectral-Based Damage Identification in Structures under Ambient Vibration', Journal of Computing in Civil Engineering, vol. 30, no. 4, pp. 04015062-04015062.
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Mohammed Oludare, I & Pradhan, B 2016, 'A decade of modern cave surveying with terrestrial laser scanning: A review of sensors, method and application development', International Journal of Speleology, vol. 45, no. 1, pp. 71-88.
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Moore, I & Sheng, D 2016, 'Note of appreciation / Note de reconnaissance', Canadian Geotechnical Journal, vol. 53, no. 12, pp. v-vii.
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Movassaghi, S, Majidi, A, Jamalipour, A, Smith, D & Abolhasan, M 2016, 'Enabling interference-aware and energy-efficient coexistence of multiple wireless body area networks with unknown dynamics', IEEE Access, vol. 4, pp. 2935-2951.
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© 2016 IEEE. This paper presents an adaptive interference mitigation scheme for multiple coexisting wireless body area networks (WBANs) based on social interaction. The proposed scheme considers the mobility of nodes within each WBAN as well as the relative movement of WBANs with respect to each other. With respect to these mobile scenarios traffic load, signal strength, and the density of sensors in a WBAN are incorporated to optimize transmission time with synchronous and parallel transmissions to significantly reduce the radio interference and energy consumption of nodes. This approach leads to higher packet delivery ratio (PDR) and longer network lifetime even with nodes dynamically moving into and out of each others interference region. We make channel assignment more energy-efficient and further reduce power consumption using transmit power control with simple channel prediction. Simulation results show that our approach maintains optimum spatial reuse with a range of channel dynamics within, and between, coexisting BANs. This protocol based on social interaction is shown to mitigate interference and minimize power consumption, and increase the spatial reuse and PDR of each WBAN, while increasing network lifetime. In the context of the adaptive interference mitigation scheme proposed, this paper also reviews the state of the art in literature on mobility, MAC layer, and power control solutions for WBANs, as well as providing a summary of interference mitigation schemes previously applied for the coexistence of WBANs.

Moyle, W, Jones, C, Sung, B, Bramble, M, O’Dwyer, S, Blumenstein, M & Estivill-Castro, V 2016, 'What Effect Does an Animal Robot Called CuDDler Have on the Engagement and Emotional Response of Older People with Dementia? A Pilot Feasibility Study', International Journal of Social Robotics, vol. 8, no. 1, pp. 145-156.
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© 2015, Springer Science+Business Media Dordrecht. The development of companion animal robots is of growing interest. These robots have recently been marketed to older adults with dementia as a means of encouraging social engagement and reducing behavioural and psychological symptoms of dementia. This paper outlines the results of a pilot study that sought to assess the feasibility and effect of using a robotic companion animal called CuDDler on engagement and emotional states of five older adults with dementia living in nursing home care. CuDDler is a prototype robot developed in Singapore. Despite their cognitive decline, the study participants raised a number of concerns regarding the feasibility and tolerability of CuDDler. The effectiveness of CuDDler was also limited in these participants, although one participant with visual agnosia benefited greatly from the one-on-one experience. The findings demonstrate the importance of companion robots being developed that are of an appropriate size, weight and shape for older people, including those with dementia, and a realistic animal shape that does not encourage thoughts of it being a toy. Our conclusions indicate the need for further studies on the development and use of companion robots, and investigation of the comparative benefits of social robots both compared to and in association with human interactions.

Ngo, NT & Indraratna, B 2016, 'Improved Performance of Rail Track Substructure Using Synthetic Inclusions: Experimental and Numerical Investigations', International Journal of Geosynthetics and Ground Engineering, vol. 2, no. 3, p. 24.
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Ballasted rail tracks offer the most important means of transporting bulk freight and passengers in terms of the sheer tonnage of traffic. Ballast is a prominent component of conventional rail infrastructure because it controls the stability and performance of track. Repetitive train loads degrade ballast grains due to breakage and the progressive accumulation of external fines or mud-pumping from the softer subgrade. They decrease the shear strength and drainage capacity of track embankments, while adversely affecting its safety and efficiency as speed restrictions are imposed and track maintenance becomes more frequent. Although synthetic inclusions such as geogrids and rubber mats placed between the ballast and subballast definitely improve track performance, further study is needed before incorporating them into existing design routines catering for future high speed trains and heavier haul trains. This paper presents the very latest knowledge of rail track geomechanics, including several important concepts and topics related to laboratory testing and discrete element modelling approaches to study the load and deformation of ballast improved by rubber mats and synthetic geogrids. This paper focuses on studies carried out at the University of Wollongong on track infrastructure, and includes examples whereby innovation progresses from theory to practice. Discrete element modelling is also used to carry out a micromechanical analysis of the ballast and geogrid interface to provide further insight into ballast subjected to shearing.

Ngo, NT, Indraratna, B & Rujikiatkamjorn, C 2016, 'Modelling geogrid-reinforced railway ballast using the discrete element method', Transportation Geotechnics, vol. 8, pp. 86-102.
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Rail ballast is an unbounded granular material that spreads laterally when subjected to train loading. Railroads can be reinforced by geogrids to reduce lateral movement and to optimize track performance. This paper presents a study of the behaviour of geogrid-reinforced ballast subjected to monotonic and cyclic loading using a large-scale direct shear box and a novel Track Process Simulation Apparatus (TPSA). The shear stress–strain response of fresh and fouled ballast reinforced by geogrid was investigated using large-scale direct shear tests subjected to normal stresses from 15 kPa to 75 kPa, where the levels of fouling varied from 20% to 95% Void Contamination Index (VCI). Cyclic tests for fresh and fouled ballast were conducted using the TPSA to realistically simulate real track conditions. The experimental results showed that a geogrid provides extra internal confinement and interlocks the aggregates in its apertures, hence reduces ballast deformation. The discrete element method (DEM) was used to model geogrid-reinforced fresh and fouled ballast subjected to monotonic and cyclic loading. Irregularly-shaped particles and geogird were simulated by clumping spherical balls together, while the coal fines were simulated by adding 1.5 mm diameter spheres into the pore spaces of ballast. The predicted stress-displacement responses obtained from the DEM were in good agreement with those measured in the laboratory, where the peak shear stress of fouled ballast decreased and the dilation of fouled ballast increased with an increasing level of fouling. The contact force distributions and the orientations of normal and shear force were analyzed to provide more insight into the behaviour of ballast subjected to shearing.

Ngo, NT, Indraratna, B, Rujikiatkamjorn, C & Mahdi Biabani, M 2016, 'Experimental and Discrete Element Modeling of Geocell-Stabilized Subballast Subjected to Cyclic Loading', Journal of Geotechnical and Geoenvironmental Engineering, vol. 142, no. 4, pp. 04015100-04015100.
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This paper presents a study of the load-deformation behavior of geocell-stabilized subballast subjected to cyclic loading using a novel track process simulation apparatus. The tests were conducted at frequencies varying from 10 to 30 Hz. This frequency range is generally representative of Australian standard gauge trains operating up to 160 km/h. The discrete-element method (DEM) was also used to model geocell-reinforced subballast under plane strain conditions. The geocell was modeled by connecting a group of small circular balls together to form the desired geometry and aperture using contact and parallel bonds. Tensile and bending tests were carried out to calibrate the model parameters adopted for simulating the geocell. To model irregularly shaped particles of subballast, clusters of bonded circular balls were used. The simulated load-deformation curves of the geocell-reinforced subballast assembly at varying cyclic load cycles were in good agreement with the experimental observations. The results indicated that the geocell decreased the vertical and lateral deformation of subballast assemblies at any given frequency. Furthermore, the DEM can also provide insight into the distribution of contact force chains, and average contact normal and shear force distributions, which cannot be determined experimentally.

Nguyen, L & Fatahi, B 2016, 'Behaviour of clay treated with cement & fibre while capturing cementation degradation and fibre failure – C3F Model', International Journal of Plasticity, vol. 81, pp. 168-195.
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Crown Copyright © 2016 Published by Elsevier Ltd. All rights reserved. Soil treated with cement becomes brittle because its shear strength decreases rapidly in a post-peak state, which is why in recent years the inclusion of fibre into soil treated with cement has become an increasingly popular research area. This paper presents a constitutive model to simulate the behaviour of the fibre reinforced cement treated soil, referred to as the improved soil composite. In this model, a non-linear failure envelope was formulated to merge with the Critical State Line (CSL) of the reconstituted soil mixture at high levels of stress in order to capture the broken cementation bonds and ruptured fibre. A non-associated plastic potential function and a general stress strain relationship that includes the softening of the composite soil were also proposed to simulate the pre-and-post peak state. Moreover, many researchers focus on the addition of fibre into sand, soft clay, and sand treated with cement, whereas the behaviour of soft clay treated with fibre and cement requires further investigation. Hence, in this study a series of undrained triaxial tests were carried out on natural Ballina clay treated with cement and 0.3%-0.5% of fibre to determine how the amount of fibre and cement affects the behaviour of soft clay. SEM images were also analysed to study the structure of the improved Ballina composite at the micro-structural level. The laboratory results indicated that the combined effects of cementation and fibre reinforcement increased the shear strength and ductility of treated soft clay. Under triaxial conditions the peak shear strength of soft clay treated with cement and fibre increases dramatically due to the formation of cementation bonds and the bridging effect provided by the fibres, and the brittleness caused by the cementation bonds breaking also improves significantly due to the inclusion of fibre. However, when shearing at a high mean effective stress the ceme...

Nguyen, L, Fatahi, B & Khabbaz, H 2016, 'Predicting the Behaviour of Fibre Reinforced Cement Treated Clay', ADVANCES IN TRANSPORTATION GEOTECHNICS III, vol. 143, pp. 153-160.
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© 2016 The Authors. Published by Elsevier B.V. Treating soft clay with cement and fibre has become an effective ground improvement technique for transport infrastructure. Application of recycled fibres in deep soil mixing columns in soft soil sections of road and rail projects is being considered by designers and clients as an efficient technique. However, the combined effect of cement and fibre at failure requires further investigation. As the effective stresses increase to a sufficiently high stress, the effect of cementation is diminished due to the degradation of cementation bonds and the fibre exhibits failure due to either complete pull-out or breakage from the soil matrix. Thus, the failure envelope of the reinforced soil gradually merges with that of un-reinforced soil at higher stresses. In this paper, a constitutive model is proposed to simulate the behaviour of the cement treated-fibre reinforced soil based on the Critical State Soil Mechanic and the Modified Cam Clay model. In particular, the proposed model captures the beneficial effects of cementation and fibre reinforcement such as the improvement in strength and ductility while the cementation degradation and the failure mechanism of the fibre are also considered. In addition, a series of un-drained triaxial tests were conducted to verify the performance of the proposed model. This paper concludes that adding fibre into the cement treated soil clearly improves its residual strength, thus, a significant increase in ductility is observed and well simulated. In this study, by modifying the mean effective stress to include the cementation degradation and the fibre failure mechanism, the proposed model results in realistic prediction for the behaviour of soil treated with cement and fibre.

Nguyen, QV, Fatahi, B & Hokmabadi, AS 2016, 'The effects of foundation size on the seismic performance of buildings considering the soil-foundation-structure interaction', Structural Engineering and Mechanics, vol. 58, no. 6, pp. 1045-1075.
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Copyright © 2016 Techno-Press, Ltd. Shallow footings are one of the most common types of foundations used to support mid-rise buildings in high risk seismic zones. Recent findings have revealed that the dynamic interaction between the soil, foundation, and the superstructure can influence the seismic response of the building during earthquakes. Accordingly, the properties of a foundation can alter the dynamic characteristics (natural frequency and damping) of the soil-foundation-structure system. In this paper the influence that shallow foundations have on the seismic response of a mid-rise moment resisting building is investigated. For this purpose, a fifteen storey moment resisting frame sitting on shallow footings with different sizes was simulated numerically using ABAQUS software. By adopting a direct calculation method, the numerical model can perform a fully nonlinear time history dynamic analysis to realistically simulate the dynamic behaviour of soil, foundation, and structure under seismic excitations. This three-dimensional numerical model accounts for the nonlinear behaviour of the soil medium and structural elements. Infinite boundary conditions were assigned to the numerical model to simulate free field boundaries, and appropriate contact elements capable of modelling sliding and separation between the foundation and soil elements are also considered. The influence of foundation size on the natural frequency of the system and structural response spectrum was also studied. The numerical results for cases of soil-foundation-structure systems with different sized foundations and fixed base conditions (excluding soil-foundation-structure interaction) in terms of lateral deformations, inter-storey drifts, rocking, and shear force distribution of the structure were then compared. Due to natural period lengthening, there was a significant reduction in the base shears when the size of the foundation was reduced. It was concluded that the size of a...

Nguyen, T, Ghabraie, K, Tran-Cong, T & Fatahi, B 2016, 'Improving Rockbolt Design in Tunnels Using Topology Optimization', International Journal of Geomechanics, vol. 16, no. 1, pp. 04015023-04015023.
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© 2015 American Society of Civil Engineers. Finding an optimum reinforcement layout for underground excavation can result in a safer and more economical design, and is therefore highly desirable. Some works in the literature have applied topology optimization in tunnel reinforcement design in which reinforced rock is modeled as homogenized isotropic material. Optimization results, therefore, do not clearly show reinforcement distributions, leading to difficulties in explaining the final outcomes. To overcome this deficiency, a more sophisticated modeling technique in which reinforcements are explicitly modeled as truss elements embedded in rock mass media is used. An optimization algorithm extending the solid isotropic material with penalization method is introduced to seek for an optimal bolt layout. To obtain the stiffest structure with a given amount of reinforced material, external work along the opening is selected as the objective function with a constraint on the volume of reinforcement. The presented technique does not depend on material models used for rock and reinforcements and can be applied to any material model. Nonlinear material behavior of rock and reinforcement is considered in this work. Through solving some typical examples, the proposed approach is proved to enhance the conventional reinforcement design and provide clear and practical reinforcement layouts.

Nguyen, TT & Indraratna, B 2016, 'Hydraulic behaviour of parallel fibres under longitudinal flow: a numerical treatment', Canadian Geotechnical Journal, vol. 53, no. 7, pp. 1081-1092.
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Modelling fluid flow through fibrous porous materials has gained increasing attention from industry and research communities. Analytical and numerical methods are commonly used to predict the hydraulic characteristics of fibrous material during fluid flow, although to date most techniques have been conducted using the same assumption that the geometric features of fibres remain unchanged. In other words, the mutual interaction between fibre elements and fluid is ignored, which undermines the actual working condition of fibres. This paper therefore presents a potential numerical approach that is capable of capturing the behaviour of a fluid–solid system. Individual fibres are simulated by the discrete element method (DEM) coupled with the concept of computational fluid dynamics (CFD), whereby the information contained in each phase is constantly exchanged and updated with other phases. In comparison with conventional solutions, including the Kozeny–Carman (K–C) fluid flow principle and other valid studies, the results show an acceptable agreement in predicting the hydraulic conductivity of a fibrous system. Subjected to laminar longitudinal flow, fibre motion is also evaluated with respect to varying bond stiffness and flow velocity. The study indicates the potential of the proposed technique in modelling drainage and filtration that is based on the hydraulic behaviour of fibrous porous geomaterials.

Nimbalkar, S & Indraratna, B 2016, 'Field Assessment of Ballasted Railroads Using Geosynthetics and Shock Mats', Procedia Engineering, vol. 143, pp. 1485-1494.
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© 2016 The Authors. Published by Elsevier B.V.The ballasted railroads form an integral part of the modern transportation infrastructure in Australia. However, they are subjected to large stresses especially on mixed traffic lines, where heavy freight trains are operated. Under such adverse operational conditions, ballast progressively degrades contributing to overall track deformations and frequent maintenance. Maintaining geometry of ballast embankments is necessary to improve safety and efficiency of railway operations. The use of artificial inclusions (geosynthetics and shock mats) as well as recycled (discarded) ballast in track can be economically viable options. In order to gain more insight, the CGRE has conducted extensive field trials on two rail lines in Bulli and Singleton in New South Wales supported by Sydney Trains and Australian Rail Track Corporation, respectively. In these studies, different types of geosynthetics (geogrid, geotextile and geocomposite) and shock mats were installed beneath the ballast layer constructed on varying subgrade conditions. Relative advantages of different geogrids were studied. Traffic induced stresses, ballast breakage, transient and permanent deformations were routinely monitored using precise instrumentation schemes. This paper discusses the details of track construction, instrumentation, monitoring processes and results of these field studies.

Oberst, S, Lai, JCS & Evans, TA 2016, 'Termites utilise clay to build structural supports and so increase foraging resources', Scientific Reports, vol. 6, no. 1.
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AbstractMany termite species use clay to build foraging galleries and mound-nests. In some cases clay is placed within excavations of their wooden food, such as living trees or timber in buildings; however the purpose for this clay is unclear. We tested the hypotheses that termites can identify load bearing wood and that they use clay to provide mechanical support of the load and thus allow them to eat the wood. In field and laboratory experiments, we show that the lower termite Coptotermes acinaciformis, the most basal species to build a mound-nest, can distinguish unloaded from loaded wood and use clay differently when eating each type. The termites target unloaded wood preferentially and use thin clay sheeting to camouflage themselves while eating the unloaded wood. The termites attack loaded wood secondarily and build thick, load-bearing clay walls when they do. The termites add clay and build thicker walls as the load-bearing wood is consumed. The use of clay to support wood under load unlocks otherwise unavailable food resources. This behaviour may represent an evolutionary step from foraging behaviour to nest building in lower termites.

Oberst, S, Zhang, Z & Lai, JCS 2016, 'The Role of Nonlinearity and Uncertainty in Assessing Disc Brake Squeal Propensity', SAE International Journal of Passenger Cars - Mechanical Systems, vol. 9, no. 3, pp. 980-986.
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Odeh, N, Abolhasan, M, Safaei, F, Franklin, DR & Mao, G 2016, 'Utility-based resource allocation for interference limited OFDMA cooperative relay networks', PHYSICAL COMMUNICATION, vol. 20, pp. 74-84.
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Omar, H, Kassim, AR, Musa, S, Darmawan, S, Takeuchi, W, Abidin, H, Rasid, MN, Samat, MN, Pour, AB & Hashim, M 2016, 'Special Issue for the 8th IGRSM International Conference and Exhibition on Geospatial & Remote Sensing (IGRSM 2016), 13-14 April 2016, Berjaya Times Square Hotel, Kuala Lumpur, Malaysia'.

Parsa-Pajouh, A, Fatahi, B & Khabbaz, H 2016, 'Experimental and Numerical Investigations to Evaluate Two-Dimensional Modeling of Vertical Drain–Assisted Preloading', International Journal of Geomechanics, vol. 16, no. 1.
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© 2015 American Society of Civil Engineers. In this study, the efficiency of proposed formulations for plane-strain modeling of vertical drain-assisted consolidation was evaluated. For this aim, the vertical drain-assisted preloading process was experimentally simulated using a fully instrumented large-scale Rowe cell. Nine pore-water-pressure transducers were installed in various locations to measure the changes in pore-water pressure during the test. Two pressure/volume controllers were connected to an infinite-volume controller to provide continuous water flow. Soft clays with predefined properties were used to form the intact and smear zones. A numerical code was developed by using the finite-difference program FLAC 2D to simulate the consolidation test. A numerical study was conducted to evaluate the efficiency of the proposed solutions for converting the axisymmetric state to a plane-strain condition and was subsequently compared with corresponding numerical analysis. From the results, it is observed that some of the proposed methods resulted in more accurate predictions of settlement and changes of pore-water pressure in the early stages of the consolidation process, whereas other proposed methods performed more accurately in the later stages of consolidation. Thus, three-dimensional modeling with actual soil-permeability properties to simulate the time-dependent behavior of soft soil improved with vertical drains is recommended.

Payne, T, Mitchell, S, Halkon, B & Bibb, R 2016, 'A systematic approach to the characterisation of human impact injury scenarios in sport', BMJ Open Sport & Exercise Medicine, vol. 2, no. 1, pp. e000017-e000017.
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Background

In contact sports (eg, American football or rugby), injuries resulting from impacts are widespread. There have been several attempts to identify and collate, within a conceptual framework, factors influencing the likelihood of an injury. To effectively define an injury event it is necessary to systematically consider all potential causal factors but none of the previous approaches are complete in this respect.

Aims

First, to develop a superior deterministic contextual sequential (DCS) model to promote a complete and logical description of interrelated injury event factors. Second, to demonstrate systematic use of the model to construct enhanced perspectives for impact-injury research.

Method

Previous models were examined and elements of best practice synthesised into a new DCS framework description categorising the types of causal factors influencing injury. The approach's internal robustness is demonstrated by consideration of its completeness, lack of redundancy and logical consistency.

Results

The model's external validity and worth are demonstrated through its use to generate superior descriptive injury models, experimental protocols and intervention opportunities. Comprehensive research perspectives have been developed using a common rugby impact-injury scenario as an example; this includes: a detailed description of the injury event, an experimental protocol for a human-on-surrogate reconstruction, and a series of practical interventions in the sport of rugby aimed at mitigating the risk of injury.

Conclusions

Our improved characterisation tool presents a structured approach to identify pertinent factors relating to an injury.

Payne, T, Mitchell, S, Halkon, B, Bibb, R & Waters, M 2016, 'Development of a synthetic human thigh impact surrogate for sports personal protective equipment testing', Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology, vol. 230, no. 1, pp. 5-16.
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Synthetic impact surrogates are widely used in the sporting goods industry in the evaluation of personal protective equipment. Existing surrogates, exemplified by those used in safety standards, have many shortcomings, primarily relating to their mass, stiffness, geometries and levels of constraint which limit their biofidelity and subsequent usefulness in personal protective equipment evaluations. In sports, absence from competition is a primary severity measure for injuries; consequently, blunt trauma injuries, such as contusions and lacerations, become pertinent and serious concerns. It is important, therefore, that synthetic surrogates provide an adequate description of these soft tissues to effectively evaluate injury risk. A novel, multi-material human thigh surrogate has been presented with consideration to the tissue structures, geometries and simulant materials used. This study presents the detailed development stages undertaken to fabricate a multi-material synthetic soft tissue surrogate with skin, subcutaneous adipose and muscle tissue components. The resultant surrogate demonstrates the successful use of sequential moulding techniques to construct a full-scale anatomical human impact surrogate which can be used in personal protective equipment testing.

Pham, BT, Pradhan, B, Tien Bui, D, Prakash, I & Dholakia, MB 2016, 'A comparative study of different machine learning methods for landslide susceptibility assessment: A case study of Uttarakhand area (India)', Environmental Modelling & Software, vol. 84, pp. 240-250.
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Landslide susceptibility assessment of Uttarakhand area of India has been done by applying five machine learning methods namely Support Vector Machines (SVM), Logistic Regression (LR), Fisher's Linear Discriminant Analysis (FLDA), Bayesian Network (BN), and Naïve Bayes (NB). Performance of these methods has been evaluated using the ROC curve and statistical index based methods. Analysis and comparison of the results show that all five landslide models performed well for landslide susceptibility assessment (AUC = 0.910–0.950). However, it has been observed that the SVM model (AUC = 0.950) has the best performance in comparison to other landslide models, followed by the LR model (AUC = 0.922), the FLDA model (AUC = 0.921), the BN model (AUC = 0.915), and the NB model (AUC = 0.910), respectively.

Pourghasemi, HR, Beheshtirad, M & Pradhan, B 2016, 'A comparative assessment of prediction capabilities of modified analytical hierarchy process (M-AHP) and Mamdani fuzzy logic models using Netcad-GIS for forest fire susceptibility mapping', Geomatics, Natural Hazards and Risk, vol. 7, no. 2, pp. 861-885.
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Pradhan, B, Abdullahi, S & Seddighi, Y 2016, 'Detection of urban environments using advanced land observing satellite phased array type L-band synthetic aperture radar data through different classification techniques', Journal of Applied Remote Sensing, vol. 10, no. 3, pp. 036029-036029.
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Pradhan, B, Jebur, MN, Shafri, HZM & Tehrany, MS 2016, 'Data Fusion Technique Using Wavelet Transform and Taguchi Methods for Automatic Landslide Detection From Airborne Laser Scanning Data and QuickBird Satellite Imagery', IEEE Transactions on Geoscience and Remote Sensing, vol. 54, no. 3, pp. 1610-1622.
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Landslide mapping is indispensable for efficient land use management and planning. Landslide inventory maps must be produced for various purposes, such as to record the landslide magnitude in an area and to examine the distribution, types, and forms of slope failures. The use of this information enables the study of landslide susceptibility, hazard, and risk, as well as of the evolution of landscapes affected by landslides. In tropical countries, precipitation during the monsoon season triggers hundreds of landslides in mountainous regions. The preparation of a landslide inventory in such regions is a challenging task because of rapid vegetation growth. Thus, enhancing the proficiency of landslide mapping using remote sensing skills is a vital task. Various techniques have been examined by researchers. This study uses a robust data fusion technique that integrates high-resolution airborne laser scanning data (LiDAR) with high-resolution QuickBird satellite imagery (2.6-m spatial resolution) to identify landslide locations in Bukit Antarabangsa, Ulu Klang, Malaysia. This idea is applied for the first time to identify landslide locations in an urban environment in tropical areas. A wavelet transform technique was employed to achieve data fusion between LiDAR and QuickBird imagery. An object-oriented classification method was used to differentiate the landslide locations from other land use/covers. The Taguchi technique was employed to optimize the segmentation parameters, whereas the rule-based technique was used for object-based classification. In addition, to assess the impact of fusion in classification and landslide analysis, the rule-based classification method was also applied on original QuickBird data which have not been fused. Landslide locations were detected, and the confusion matrix was used to examine the proficiency and reliability of the results. The achieved overall accuracy and kappa coefficient were 90.06% and 0.84, respectively, for fus...

Pradhan, B, Tehrany, MS & Jebur, MN 2016, 'A New Semiautomated Detection Mapping of Flood Extent From TerraSAR-X Satellite Image Using Rule-Based Classification and Taguchi Optimization Techniques', IEEE Transactions on Geoscience and Remote Sensing, vol. 54, no. 7, pp. 4331-4342.
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Floods are among the most destructive natural disasters worldwide. In flood disaster management programs, flood mapping is an initial step. This research proposes an efficient methodology to recognize and map flooded areas by using TerraSAR-X imagery. First, a TerraSAR-X satellite image was captured during a flood event in Kuala Terengganu, Malaysia, to map the inundated areas. Multispectral Landsat imagery was then used to detect water bodies prior to the flooding. In synthetic aperture radar (SAR) imagery, the water bodies and flood locations appear in black; thus, both objects were classified as one. To overcome this drawback, the class of the water bodies was extracted from the Landsat image and then subtracted from that extracted from the TerraSAR-X image. The remaining water bodies represented the flooded locations. Object-oriented classification and Taguchi method were implemented for both images. The Landsat images were categorized into three classes, namely, urban, vegetation, and water bodies. By contrast, only water bodies were extracted from the TerraSAR-X image. The classification results were then evaluated using a confusion matrix. To examine the efficiency of the proposed method, iterative self-organizing data analysis technique (ISODATA) classification method was applied on TerraSAR-X after employing the segmentation process during object-oriented-rule-based method, and the results were compared. The overall accuracy values of the classified maps derived from TerraSAR-X using the rule-based method and Landsat imagery were 86.18 and 93.04, respectively. Consequently, the flooded locations were recognized and mapped by subtracting the two classes of water bodies from these images. The acquired overall accuracy for TerraSAR-X using ISODATA was considerably low at only 57.98. The current research combined the methods and the optimization technique used as an innovative flood detection application. The successful production of a reliable and...

Rasekh, H & McCarthy, TJ 2016, 'DELIVERING SUSTAINABLE BUILDING PROJECTS – CHALLENGES, REALITY AND SUCCESS', Journal of Green Building, vol. 11, no. 3, pp. 143-161.
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This research concerns the delivery of sustainable building projects. These projects are defined as those which either attempt to achieve green ratings or are claimed to address certain sustainability issues. A key focus is to examine how the client's vision for sustainability is achieved or compromised by the practicality of construction. Two sustainability rating systems, the Australian Green Star and the Living Building Challenge from the U.S. are discussed. This research examines two projects; one university multipurpose building (SMART Infrastructure Facility); and an advanced research facility, the Sustainable Buildings Research Centre (SBRC). The methodology used is semi-structured interviews of key participants and stakeholders for the two university building. The outcome of this research indicates that environmental rating systems are useful tools to construct reasonably sustainable buildings. Many interviewees, however, believe that for their next projects the concern would be to continue to construct sustainable buildings but not necessarily by following the strict criteria and reporting requirements of the environmental rating system.

Rizeei, HM, Saharkhiz, MA, Pradhan, B & Ahmad, N 2016, 'Soil erosion prediction based on land cover dynamics at the Semenyih watershed in Malaysia using LTM and USLE models', Geocarto International, vol. 31, no. 10, pp. 1158-1177.
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This study attempts to identify and forecast future land cover (LC) by using the Land Transformation Model (LTM), which considers pixel changes in the past and makes predictions using influential spatial features. LTM applies the Artificial Neural Networks algorithm) in conducting the analysis. In line with these objectives, two satellite images (Spot 5 acquired in 2004 and 2010) were classified using the Maximum Likelihood method for the change detection analysis. Consequently, LC maps from 2004 to 2010 with six classes (forest, agriculture, oil palm cultivations, open area, urban, and water bodies) were generated from the test area. A prediction was made on the actual soil erosion and the soil erosion rate using the Universal Soil Loss Equation (USLE) combined with remote sensing and GIS in the Semenyih watershed for 2004 and 2010 and projected to 2016. Actual and potential soil erosion maps from 2004 to 2010 and projected to 2016 were eventually generated. The results of the LC change detections indicated that three major changes were predicted from 2004 to 2016 (a period of 12 years): (1) forest cover and open area significantly decreased at rates of almost 30 and 8 km2, respectively; (2) cultivated land and oil palm have shown an increment in sizes at rates of 25.02 and 5.77 km2, respectively; and, (3) settlement and Urbanization has intensified also by almost 5 km2. Soil erosion risk analysis results also showed that the Semenyih basin exhibited an average annual soil erosion between 143.35 ton ha−1 year−1 in 2004 and 151 in 2010, followed by the expected 162.24 ton ha−1 year−1. These results indicated that Semenyih is prone to water erosion by 2016. The wide range of erosion classes were estimated at a very low level (0–1 t/ha/year) and mainly located on steep lands and forest areas. This study has shown that using both LTM and USLE in combination with remote sensing and GIS is a suitable method for forecasting LC and accurately measuring the amo...

Sahoo, M, Sahoo, S, Dhar, A & Pradhan, B 2016, 'Effectiveness evaluation of objective and subjective weighting methods for aquifer vulnerability assessment in urban context', Journal of Hydrology, vol. 541, pp. 1303-1315.
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Sameen, MI, Nahhas, FH, Buraihi, FH, Pradhan, B & Shariff, ARBM 2016, 'A refined classification approach by integrating Landsat Operational Land Imager (OLI) and RADARSAT-2 imagery for land-use and land-cover mapping in a tropical area', International Journal of Remote Sensing, vol. 37, no. 10, pp. 2358-2375.
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Sangchini, EK, Emami, SN, Tahmasebipour, N, Pourghasemi, HR, Naghibi, SA, Arami, SA & Pradhan, B 2016, 'Assessment and comparison of combined bivariate and AHP models with logistic regression for landslide susceptibility mapping in the Chaharmahal-e-Bakhtiari Province, Iran', Arabian Journal of Geosciences, vol. 9, no. 3, p. 201.
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Siyahghalati, S, Saraf, AK, Pradhan, B, Jebur, MN & tehrany, MS 2016, 'Rule-based semi-automated approach for the detection of landslides induced by 18 September 2011 Sikkim, Himalaya, earthquake using IRS LISS3 satellite images', Geomatics, Natural Hazards and Risk, vol. 7, no. 1, pp. 326-344.
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Landslide is considered as one of the most devastating and most costly natural hazards in highlands, which is triggered mainly by rainfalls or earthquakes. In comparison with other methods, landslide mapping and monitoring via remote sensing data products are considered as the least expensive method of data collection. The current research attempts to detect landslides which occurred due to a 6.9 magnitude earthquake in Sikkim Himalaya, India, on 18 September 2011 and also to establish the spatial relationship between landslides and the slope of the terrain. To detect the landslides, decision tree method was applied on two Indian remote sensing satellites linear imaging self-scanning sensor (LISS III) images acquired from 2007 and 2011 which were taken before and after the earthquake. As the study area was relatively huge for identifying the landslides, the region was separated into two parts: “tested study area” and “real study area”. The overall accuracy of landslide detection was 76%, and 75% for tested and real study area, respectively. Then, the spatial relationship between the landslides and the slope of the terrain was conducted using the digital elevation model. The results revealed that most of the landslides occurred between the slope of 25° and 45° covering 2.3 km2 and no landslide recorded in the slope of 65°–90° in the real study area. The results obtained in this study may be useful for decision-making and policy support towards reconstruction effort after the landslide occurrence. In addition, the information can be useful for reducing the risk of potential damages to substructures and properties by developing new and efficient strategies.

Subhani, M, Li, J & Samali, B 2016, 'Separation of longitudinal and flexural wave in a cylindrical structure based on sensor arrangement for non-destructive evaluation', Journal of Civil Structural Health Monitoring, vol. 6, no. 3, pp. 411-427.
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© 2016, Springer-Verlag Berlin Heidelberg. Low strain integrity testing is commonly used to assess the in situ condition of the poles or piles. For poles, it is important to calculate the embedment length and location of damage which is highly influenced by the accurate determination of the wave velocity. In general, depending on impact location and orientation, both longitudinal and bending waves may generate inside the pole, and these two waves have very distinct characteristics and wave velocity. These differences are even more prominent in the low frequency which is usually induced in the low strain non-destructive testing. Consequently, it will be useful if these two waves can be separated for the condition assessment of the poles. In this paper, a numerical analysis is performed on a pole considering that both waves are generated, and a method is proposed to differentiate these two waves based on an appropriate sensor arrangement that includes the location and the orientation of the sensors. Continuous wavelet transform is applied on the numerical signal to calculate the phase velocity of the waves and compared with analytical phase velocity curves. From the results, it can be seen that appropriate location and orientation of the sensors can separate the longitudinal and flexural waves as they match significantly well with the corresponding analytical phase velocity curves of these two waves.

Subhani, M, Li, J, Samali, B & Crews, K 2016, 'Reducing the effect of wave dispersion in a timber pole based on transversely isotropic material modelling', Construction and Building Materials, vol. 102, pp. 985-998.
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© 2015 Elsevier Ltd. Round timbers are used for telecommunication and power distribution networks, jetties, piles, short span bridges etc. To assess the condition of these cylindrical shape timber structures, bulk and elementary wave theory are usually used. Even though guided wave can represents the actual wave behaviour, a great deal complexity exists to model stress wave propagation within an orthotropic media, such as timber. In this paper, timber is modelled as transversely isotropic material without compromising the accuracy to a great extent. Dispersion curves and mode shapes are used to propose an experimental set up in terms of the input frequency and bandwidth of the signal, the orientation of the sensor and the distance between the sensors in order to reduce the effect of the dispersion in the output signal. Some example based on the simulated signal is also discussed to evaluate the proposed experimental set up.

Sun, D, You, G, Annan, Z & Daichao, S 2016, 'Soil–water retention curves and microstructures of undisturbed and compacted Guilin lateritic clay', Bulletin of Engineering Geology and the Environment, vol. 75, no. 2, pp. 781-791.
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Sun, D, Zhang, J, Gao, Y & Sheng, D 2016, 'Influence of Suction History on Hydraulic and Stress-Strain Behavior of Unsaturated Soils', International Journal of Geomechanics, vol. 16, no. 6.
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Thirukumaran, S & Indraratna, B 2016, 'A review of shear strength models for rock joints subjected to constant normal stiffness', Journal of Rock Mechanics and Geotechnical Engineering, vol. 8, no. 3, pp. 405-414.
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The typical shear behaviour of rough joints has been studied under constant normal load/stress (CNL) boundary conditions, but recent studies have shown that this boundary condition may not replicate true practical situations. Constant normal stiffness (CNS) is more appropriate to describe the stress-strain response of field joints since the CNS boundary condition is more realistic than CNL. The practical implications of CNS are movements of unstable blocks in the roof or walls of an underground excavation, reinforced rock wedges sliding in a rock slope or foundation, and the vertical movement of rock-socketed concrete piles. In this paper, the highlights and limitations of the existing models used to predict the shear strength/behaviour of joints under CNS conditions are discussed in depth.

Thirukumaran, S, Indraratna, B, Brown, ET & Kaiser, PK 2016, 'Stability of a Rock Block in a Tunnel Roof Under Constant Normal Stiffness Conditions', Rock Mechanics and Rock Engineering, vol. 49, no. 4, pp. 1587-1593.
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Tien Bui, D, Ho, T-C, Pradhan, B, Pham, B-T, Nhu, V-H & Revhaug, I 2016, 'GIS-based modeling of rainfall-induced landslides using data mining-based functional trees classifier with AdaBoost, Bagging, and MultiBoost ensemble frameworks', Environmental Earth Sciences, vol. 75, no. 14, p. 1101.
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Tien Bui, D, Pradhan, B, Nampak, H, Bui, Q-T, Tran, Q-A & Nguyen, Q-P 2016, 'Hybrid artificial intelligence approach based on neural fuzzy inference model and metaheuristic optimization for flood susceptibilitgy modeling in a high-frequency tropical cyclone area using GIS', Journal of Hydrology, vol. 540, pp. 317-330.
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This paper proposes a new artificial intelligence approach based on neural fuzzy inference system and metaheuristic optimization for flood susceptibility modeling, namely MONF. In the new approach, the neural fuzzy inference system was used to create an initial flood susceptibility model and then the model was optimized using two metaheuristic algorithms, Evolutionary Genetic and Particle Swarm Optimization. A high-frequency tropical cyclone area of the Tuong Duong district in Central Vietnam was used as a case study. First, a GIS database for the study area was constructed. The database that includes 76 historical flood inundated areas and ten flood influencing factors was used to develop and validate the proposed model. Root Mean Square Error (RMSE), Mean Absolute Error (MAE), Receiver Operating Characteristic (ROC) curve, and area under the ROC curve (AUC) were used to assess the model performance and its prediction capability. Experimental results showed that the proposed model has high performance on both the training (RMSE = 0.306, MAE = 0.094, AUC = 0.962) and validation dataset (RMSE = 0.362, MAE = 0.130, AUC = 0.911). The usability of the proposed model was evaluated by comparing with those obtained from state-of-the art benchmark soft computing techniques such as J48 Decision Tree, Random Forest, Multi-layer Perceptron Neural Network, Support Vector Machine, and Adaptive Neuro Fuzzy Inference System. The results show that the proposed MONF model outperforms the above benchmark models; we conclude that the MONF model is a new alternative tool that should be used in flood susceptibility mapping. The result in this study is useful for planners and decision makers for sustainable management of flood-prone areas.

Tien Bui, D, Tuan, TA, Klempe, H, Pradhan, B & Revhaug, I 2016, 'Spatial prediction models for shallow landslide hazards: a comparative assessment of the efficacy of support vector machines, artificial neural networks, kernel logistic regression, and logistic model tree', Landslides, vol. 13, no. 2, pp. 361-378.
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Preparation of landslide susceptibility maps is considered as the first important step in landslide risk assessments, but these maps are accepted as an end product that can be used for land use planning. The main objective of this study is to explore some new state-of-the-art sophisticated machine learning techniques and introduce a framework for training and validation of shallow landslide susceptibility models by using the latest statistical methods. The Son La hydropower basin (Vietnam) was selected as a case study. First, a landslide inventory map was constructed using the historical landslide locations from two national projects in Vietnam. A total of 12 landslide conditioning factors were then constructed from various data sources. Landslide locations were randomly split into a ratio of 70:30 for training and validating the models. To choose the best subset of conditioning factors, predictive ability of the factors were assessed using the Information Gain Ratio with 10-fold cross-validation technique. Factors with null predictive ability were removed to optimize the models. Subsequently, five landslide models were built using support vector machines (SVM), multi-layer perceptron neural networks (MLP Neural Nets), radial basis function neural networks (RBF Neural Nets), kernel logistic regression (KLR), and logistic model trees (LMT). The resulting models were validated and compared using the receive operating characteristic (ROC), Kappa index, and several statistical evaluation measures. Additionally, Friedman and Wilcoxon signed-rank tests were applied to confirm significant statistical differences among the five machine learning models employed in this study. Overall, the MLP Neural Nets model has the highest prediction capability (90.2 %), followed by the SVM model (88.7 %) and the KLR model (87.9 %), the RBF Neural Nets model (87.1 %), and the LMT model (86.1 %). Results revealed that both the KLR and the LMT models showed promising methods fo...

Wang, L 2016, 'Discussion of “Geometrical Method for Evaluating the Internal Instability of Granular Filters Based on Constriction Size Distribution” by Buddhima Indraratna, Jahanzaib Israr, and Cholachat Rujikiatkamjorn', Journal of Geotechnical and Geoenvironmental Engineering, vol. 142, no. 9, pp. 07016020-07016020.
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Wang, Q, Wang, S, Sloan, SW, Sheng, D & Pakzad, R 2016, 'Experimental investigation of pressure grouting in sand', Soils and Foundations, vol. 56, no. 2, pp. 161-173.
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Pressure grouting technology has been widely adopted in ground improvement and soil stabilization. To better understand the grout evolution and diffusion process upon pressure grouting injection in sand, laboratory-scale tests were carried out on loose sand under confined boundary conditions, with different grout water/cement (w/c) ratios (0.5 and 1) and soil degrees of saturation (ranging from 5% to 60%) taken into account. By comparing the injected grout volume, the grout bulb volume and density, and the characteristics of the grouted bulbs (dimension and shape) obtained at increasing grouting pressure, the main features of the pressure grouting process were revealed. The injected grout volume increased almost linearly with the grouting pressure, and a lower volume of grout could be injected for a lower w/c ratio at the same grouting pressure, representing a lower injectability. An increase in the grouting pressure leads to an enlarged grout bulb dimension for both w/c ratios, and this increase shifts the grout diffusion process from being dominated by compaction to one involving a fracture-like pattern. Generally, a spherical grout bulb is obtained at a lower w/c ratio of 0.5; however, at the higher w/c ratio of 1, fracture starts to occur even at a low grouting pressure of 100 kPa and continues to propagate as the grouting pressure increases. The influence of the degree of saturation of the soil was significant on both the injectability and the characteristics of the grout bulbs, since the cohesion of the unsaturated sand changed along with it. When Sr exceeds 5%, the volume of the injected grout decreases, but then increases after a threshold value of approximately 40%. Conversely, compaction grouting seems to be dominant at the threshold Sr value, while fractures tend to appear at both lower and higher degrees of saturation. A considerable amount of bleeding occurred with the two main diffusion processes during pressure grouting. The w/c ratio see...

Wang, SY, Sloan, SW, Sheng, DC & Tang, CA 2016, '3D numerical analysis of crack propagation of heterogeneous notched rock under uniaxial tension', Tectonophysics, vol. 677-678, pp. 45-67.
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Wang, Y, Li, B, Wang, Y, Chen, F, Zhang, B & Li, Z 2016, 'Robust Bayesian non-parametric dictionary learning with heterogeneous Gaussian noise', Computer Vision and Image Understanding, vol. 150, pp. 31-43.
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Bayesian non-parametric dictionary learning has become popular in computer vision applications due to its ability of dictionary size decision. A common assumption of this modelling approach is to place Gaussian priors on both dictionary matrix and weighting matrix. Although such simple treatment has a number of merits such as conjugate priors and easy inference, it may violate the reality since there may exist heterogeneous noise in a digital image. In this paper, we consider a general noise model for Bayesian non-parametric dictionary learning, which is able to adapt images with heterogeneous Gaussian noise. To this end, we adopt Student's t distributions as priors of heterogeneous noise for both dictionary matrix and weighting matrix. As an infinite Gaussian scale mixture, Student's t not only retains the similar properties as Gaussian but also tolerates different scales of noise. We propose an approximate inference algorithm, combining Gibbs sampling and empirical Bayesian, to estimate the posterior distribution of parameters. The experimental results show that the proposed model can clearly outperform the counterpart with Gaussian prior and the prevailing parametric methods in image de-noising with heterogeneous noise.

Wijayaratna, KP & Dixit, VV 2016, 'Impact of information on risk attitudes: Implications on valuation of reliability and information', Journal of Choice Modelling, vol. 20, pp. 16-34.
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Risk attitudes are an important behavioural characteristic that influences people's valuation of information and reliability. In a transport context, information has become widely accessible to road users through ITS systems, GPS technology and the internet justifying the importance of understanding the valuation of information by travellers. There have been a number of studies that have looked at the value of information and the value of reliability for a road user. However, to date there has not been a study that explicitly evaluates the impact of having information within a choice set on an individual's risk attitudes, which ultimately affects their valuation for information and reliability. This study conducts a controlled laboratory experiment, using methods of experimental economics, to measure the risk attitudes of users with and without the presence of information in the choice set. A model derived from Expected Utility Theory is used to infer the risk attitudes of the participants. The results of the analysis indicate that the presence of information in the choice set reduces risk aversion, which causes a reduction in people's valuation of information and reliability. It is critical to systematically incorporate these differences into behaviour models, since neglecting this fundamental difference could result in erroneous policy decisions, with respect to overpricing information, or inappropriately allocating funds for information systems.

Wu, Y, Shivakumara, P, Lu, T, Tan, CL, Blumenstein, M & Kumar, GH 2016, 'Contour Restoration of Text Components for Recognition in Video/Scene Images', IEEE Transactions on Image Processing, vol. 25, no. 12, pp. 5622-5634.
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Text recognition in video/natural scene images has gained significant attention in the field of image processing in many computer vision applications, which is much more challenging than recognition in plain background images. In this work, we aim to restore complete character contours in video/scene images from gray values, in contrast to the conventional techniques that consider edge images/binary information as inputs for text detection and recognition. We explore and utilize the strengths of zero crossing points given by the Laplacian to identify stroke candidate pixels (SPC). For each SPC pair, we propose new symmetry features based on gradient magnitude and Fourier phase angles to identify probable stroke candidate pairs (PSCP). The same symmetry properties are proposed at the PSCP level to choose seed stroke candidate pairs (SSCP). Finally, an iterative algorithm is proposed for SSCP to restore complete character contours. Experimental results on benchmark databases, namely, the ICDAR family of video and natural scenes, Street View Data (SVT), and MSRA datasets, show that the proposed technique outperforms the existing techniques in terms of both quality measures and recognition rate. We also show that character contour restoration is effective for text detection in video and natural scene images.

Xie, Q, Zhang, N, Zhang, B & Ji, J 2016, 'Boundary condition handling approaches for the model reduction of a vehicle frame', MECHANICAL SYSTEMS AND SIGNAL PROCESSING, vol. 75, pp. 123-137.
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© © 2016 Elsevier Ltd. All rights reserved. In order to apply model reduction technique to improve the computational efficiency for the large-scale FEM model of a vehicle, this paper presents the handling approaches for three widely-used boundary conditions, namely fixed boundary condition (FBC), prescribed motion (PSM) and coupling (COUP), respectively. It is found that iterated improved reduction system (IIRS) reduction method tends to generate better reduction approximation. Guyan method is not sensitive to the sequence of reduction and constraint under FBC, and can thus provide flexibility in handling different boundary conditions for the same system. As for PSM, 'constraint first' is recommended no matter which reduction method is used, and then separate reduction models can be coupled to form a new model with relative small dofs. By selecting appropriate master dofs for model reduction, the coupled model based on reduced models could produce same results as the original full one.

Yang, C, Carter, JP, Sheng, D & Sloan, SW 2016, 'An isotach elastoplastic constitutive model for natural soft clays', Computers and Geotechnics, vol. 77, pp. 134-155.
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The time and strain rate dependency observed in natural soft clays is formulated within the framework of conventional elastoplasticity. Creep of soft clays is essentially like the response of an overdamped oscillatory system, i.e., the strain rate decays in an exponential manner. A characteristic strain rate and time relationship is presented based on data from creep tests on a large number of different soft clays. The evolutionary change of strain rate is found to affect the mechanical response of soft clays in an isotach manner. Taking strain rate as another stress-like variable, a loading-isotach (LI) yield curve is proposed, which describes the combined hardening mechanisms of loading and variation of strain rate. Incorporation of this LI yield curve into critical state soil mechanics results in an isotach elastoplastic (IEP) model in triaxial stress-strain-strain rate space, which has been dubbed 'Hunter Clay'. The effects of fabric anisotropy and inter-particle cementation, which are typical features of natural soft clays, are also introduced to produce an advanced hierarchical constitutive model for soft clay. Qualitative predictions are first described and compared with the characteristic behaviour of natural soft clays. Experimental validations using test data for two soft clays are then carried out, and comparisons of the model predictions and experimental data demonstrate the capability of the model in reproducing realistic behaviour of natural soft clays. This work confirms that the complex mechanical behaviour of natural soft clays can be reproduced satisfactorily within the general framework of classical plasticity theory.

Youssef, AM, Al-kathery, M, Pradhan, B & El-sahly, T 2016, 'Debris flow impact assessment along the Al-Raith Road, Kingdom of Saudi Arabia, using remote sensing data and field investigations', Geomatics, Natural Hazards and Risk, vol. 7, no. 2, pp. 620-638.
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Youssef, AM, Pradhan, B & Sefry, SA 2016, 'Flash flood susceptibility assessment in Jeddah city (Kingdom of Saudi Arabia) using bivariate and multivariate statistical models', Environmental Earth Sciences, vol. 75, no. 1, p. 12.
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The city of Jeddah (Saudi Arabia) has experienced two catastrophic flash flood events in 2009 and 2011. These flood events had catastrophic effect on human lives and livelihoods around the wadi Muraikh, wadi Qus, wadi Methweb, and wadi Ghulail in which 113 people were dead and with 10,000 houses and 17,000 vehicles were damaged. Thus, a comprehensive flood management is required. The flood management requires information on different aspects such as the hydrological, geotechnical, environmental, social, and economic aspects of flooding. Flood susceptibility mapping for any area helps the decision makers to understand the flood trends and can aid in appropriate planning and flood prevention. In this study, two models were used for the generation of flood susceptibility maps for the Jeddah region. The first model includes bivariate probability analysis (frequency ratio), and the second model uses the multivariate analysis. For the multivariate model, the acquired weights of the FR model were entered into the logistic regression model to evaluate the correlation between flood occurrence and each related factor. This integration will overcome some of the weakness of the logistic regression, and the performance the LR will be enhanced. A flood inventory map was prepared with a total of 127 flood locations. These flood locations were extracted from different sources including field investigation and high-resolution satellite image (IKONOS 1 m). These flood locations were randomly split into two groups, one dataset representing 70 % was used for training the models, and the remaining 30 % was used for models validation. Various independent flood-related factors such as slope, elevation, curvature, geology, landuse, soil drain, and distance from streams were included. The impact of each independent flood-related factors on flooding was evaluated by analyzing each independent factor with the historical flood inventory data. The training and validation datasets w...

Youssef, AM, Sefry, SA, Pradhan, B & Alfadail, EA 2016, 'Analysis on causes of flash flood in Jeddah city (Kingdom of Saudi Arabia) of 2009 and 2011 using multi-sensor remote sensing data and GIS', Geomatics, Natural Hazards and Risk, vol. 7, no. 3, pp. 1018-1042.
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The Jeddah city is located in a coastal plain area, in the middle of the western side of the Kingdom of Saudi Arabia, bounded by the Red Sea to the west and mountains to the east. Jeddah city receives rainfall runoff from the foothills through different drainage pathways (wadis). During intense rainfall events, runoff flows westward from the hills and mountains towards the Red Sea, causing flash floods in the urban areas along the pathways of these wadis. Two major flash flood events occurred in Jeddah city during 20 November 2009 - January 2011. These events were characterized by rainfall precipitation values of 70 and 111 mm, respectively. Each flash flood event has duration of three hours. The impact of these two flood events have been disastrous causing extensive flooding that killed 113 people in 2009 and damaged infrastructure and property (more than 10,000 homes and 17,000 vehicles). This study deals with the analysis of the different factors that caused these flash flood events. The results indicate that the causes of these floods are related to a number of factors which play as a major contribution to the worsening of the flood disaster. These factors were classified into the following: geomorphological features, anthropogenic activities (urban changes), network and catchment factors, and rainfall and climatic changes factors. The climatic changes have a major impact on the rainfall intensity and will appear more in the future. Other factors related to the wadis tributaries are narrow passes, and high slope of the wadi has additional impacts in the flash floods in the area. The anthropogenic activities include the proliferation of slums and construction in the valleys coupled with the lack of suitable water streams to accommodate the amount of water flowing and the presence of dirt led to the direction of flow.

Yu, Y, Dackermann, U, Li, J & Subhani, M 2016, 'Condition Assessment of Timber Utility Poles Based on a Hierarchical Data Fusion Model', JOURNAL OF COMPUTING IN CIVIL ENGINEERING, vol. 30, no. 5, pp. 04016010-1-04016010-13.
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© 2016 American Society of Civil Engineers. This paper proposes a novel hierarchical data fusion technique for the non-destructive testing (NDT) and condition assessment of timber utility poles. The new method analyzes stress wave data from multisensor and multiexcitation guided wave testing using a hierarchical data fusion model consisting of feature extraction, data compression, pattern recognition, and decision fusion algorithms. The researchers validate the proposed technique using guided wave tests of a sample of in situ timber poles. The actual health states of these poles are known from autopsies conducted after the testing, forming a ground-truth for supervised classification. In the proposed method, a data fusion level extracts the main features from the sampled stress wave signals using power spectrum density (PSD) estimation, wavelet packet transform (WPT), and empirical mode decomposition (EMD). These features are then compiled to a feature vector via real-number encoding and sent to the next level for further processing. Principal component analysis (PCA) is also adopted for feature compression and to minimize information redundancy and noise interference. In the feature fusion level, two classifiers based on support vector machine (SVM) are applied to sensor separated data of the two excitation types and the pole condition is identified. In the decision making fusion level, the Dempster-Shafer (D-S) evidence theory is employed to integrate the results from the individual sensors obtaining a final decision. The results of the in situ timber pole testing show that the proposed hierarchical data fusion model was able to distinguish between healthy and faulty poles, demonstrating the effectiveness of the new method.

Yu, Y, Li, Y, Li, J & Gu, X 2016, 'A hysteresis model for dynamic behaviour of magnetorheological elastomer base isolator', Smart Materials and Structures, vol. 25, no. 5, pp. 055029-055029.
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© 2016 IOP Publishing Ltd. In recent years, an adaptively tuned magnetorheological elastomer (MRE) isolator for a base isolation system has been designed and tested with the benefits of low power cost, fail safe manner and fast responses. To make full use of this striking device for design of smart structures, a highly precise model should be developed to effectively and accurately forecast the shear force of the device in real-time so as to adopt a proper control strategy to improve the responses of the protected structures. In this work, a novel mechanical model is presented to characterize this nonlinear hysteresis for its implementation in structural vibration control. This model employs the displacement and velocity of the device as well as the applied current as the inputs and just has the limited constant parameters to be identified compared with some classical hysteretic models such as Bouc-Wen, improved Dahl and LuGre models. Performance evaluation of this novel hysteresis model has been conducted based on the testing data from an MRE base isolator. The results show that the proposed model has high modelling accuracy and is able to perfectly portray the unique and complicated behaviours of the device with various excitations.

Zhang, S, Sheng, D, Zhao, G, Niu, F & He, Z 2016, 'Analysis of frost heave mechanisms in a high-speed railway embankment', Canadian Geotechnical Journal, vol. 53, no. 3, pp. 520-529.
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The Harbin–Dalian high-speed railway in northeastern China has a significant portion of track foundation built on seasonally frozen ground. Wide-spread frost heave was observed during the first winter of its operation and the heave occurred mainly in coarse fills that were considered not susceptible to frost heave. This paper first presents the field data of frost heave and frost depth observed along the railway. It then analyses alternative mechanisms that have been considered to have caused the observed frost heave. The three most likely mechanisms are poor quality control of fine content in the coarse fill, the top-down water supply mechanism, and the bottom-up water supply mechanism. The likelihoods of these mechanisms are analysed against observed field data, using a one-dimensional frost heave model. The results indicate that the most likely explanation for the unexpected frost heave is a combined action of different mechanisms.

Zhang, S, Teng, J, He, Z & Sheng, D 2016, 'Importance of vapor flow in unsaturated freezing soil: a numerical study', Cold Regions Science and Technology, vol. 126, pp. 1-9.
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Zhang, S, Teng, J, He, Z, Liu, Y, Liang, S, Yao, Y & Sheng, D 2016, 'Canopy effect caused by vapour transfer in covered freezing soils', Géotechnique, vol. 66, no. 11, pp. 927-940.
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Canopy effect in this paper refers to the phenomenon whereby moisture accumulates underneath an impervious cover. Field observations reveal that the canopy effect can occur in relatively dry soils where the groundwater table is deep and can lead to full saturation of the soil immediately underneath the impervious cover. However, numerical analysis based on existing theories of heat and mass transfer in unsaturated soils can only reproduce a minor amount of moisture accumulation caused by an impervious cover, particularly when the groundwater table is relatively deep. In an attempt to explain the observed canopy effect in the field, this paper proposes a new mechanism of moisture accumulation in unsaturated freezing soils: vapour transfer in such a soil is accelerated by the process of vapour–ice desublimation. A new approach for modelling moisture and heat movements is proposed in which phase changes during the evaporation, condensation and desublimation of vapour flow are considered. A laboratory device is designed specifically to study vapour transfer in unsaturated freezing soils. The test results reveal that vapour transfer can lead to significant moisture and ice accumulation near the freezing end of a soil specimen. The computed results show that the proposed model can indeed reproduce the unusual moisture accumulation observed in relatively dry soils. The results also demonstrate that soil freezing fed by vapour transfer can result in a water content that is close to full saturation. Because vapour transfer is seldom considered in geotechnical design, the canopy effect deserves greater attention during construction and earth works in cold and arid regions.

Zhang, X, Ding, Y, Sheng, D, Sloan, SW & Huang, W 2016, 'Quasi-static collapse of two-dimensional granular columns: insight from continuum modelling', Granular Matter, vol. 18, no. 3.
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We investigate numerically the mechanism governing the quasi-static collapse of two-dimensional granular columns using a recently proposed continuum approach, the particle finite element method (PFEM), which inherits both the solid mathematical foundation of the traditional finite element method and the flexibility of particle methods in simulating ultra-large deformation problems. The typical collapse patterns of granular columns are reproduced in the PFEM simulation and the physical mechanism behind the collapse phenomenon is provided. The collapse processes obtained from the PFEM simulation are compared to experimental observations and discrete element modeling, where a satisfactory agreement is achieved. The effects of the macro density and friction angle of the granular matter, as well as the roughness of the wall surfaces on the quasi-static collapse, are also investigated in this paper. Furthermore, our simulations reveal new quasi-static collapse patterns, as supplements to the ones already observed in the experimental tests, due to the change of the roughness of the basal surface.

Zhang, X, Sheng, D, Sloan, SW & Krabbenhoft, K 2016, 'Second-order cone programming formulation for consolidation analysis of saturated porous media', Computational Mechanics, vol. 58, no. 1, pp. 29-43.
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Zhang, Z, Halkon, B, Chou, SM & Qu, X 2016, 'A novel phase-aligned analysis on motion patterns of table tennis strokes', International Journal of Performance Analysis in Sport, vol. 16, no. 1, pp. 305-316.
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© 2016, Routledge. All rights reserved. A wide range of human motion represent repetitive patterns particularly in racket sports. Quantitative analysis of the continuous variables during the different phases of the motion cycle helps to investigate more deeply the specific movement of the racket or player. Table tennis biomechanics research to date lacks the necessary detail of phase decomposition and phase-based quantitative analysis. Therefore, this study proposes a novel velocity-based piecewise alignment method to identify the different phases of a table tennis forehand stroke. A controlled experiment was conducted on a number of players of two differing ability levels (experts vs. novices) to implement this novel methodology. Detailed results are shown for the quantitative analysis on multiple strokes of the two groups of participants. Significant differences were found in both the displacement and velocity of the racket movement in the backswing, forward swing and follow-through phases. For example, it is clear that experts’ strokes show higher racket resultant velocity than novices during both the forward swing and follow-through phases by up to a factor of two. Furthermore, the phase-based approach to analysing racket motions leads to interrogation over a greater duration than the traditional time-based method which is generally only concerned with impact ±0.25s.

Zhang, Z, Oberst, S & Lai, JCS 2016, 'Instability analysis of friction oscillators with uncertainty in the friction law distribution', Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, vol. 230, no. 6, pp. 948-958.
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Despite substantial research efforts in the past two decades, the prediction of brake squeal propensity, as a significant noise, vibration and harshness (NVH) issue to automotive manufactures, is as difficult as ever. This is due to the complexity of the interacting mechanisms (e.g. stick-slip, sprag-slip, mode coupling and hammering effect) and the uncertain operating conditions (temperature, pressure). In particular, two major aspects in brake squeal have attracted significant attention recently: nonlinearity and uncertainty. The fugitiveness of brake squeal could be attributed to a number of factors including the difficulty in accurately modelling friction. In this paper, the influence of the uncertainty arising from the tribological aspect in brake squeal prediction is analysed. Three types of friction models, namely the Amonton-Coulomb model, the velocity-dependent model and the LuGre model, are randomly assigned to a group of interconnected oscillators which model the dynamics of a brake system. The complex eigenvalue analysis, as a standard stability analysis tool, and the friction work calculation are performed to investigate the probability for instability arising from the uncertainty in the friction models. The results are discussed with a view to apply this approach to the analysis of the squeal propensity for a full brake system.

Zhang, Z, Oberst, S & Lai, JCS 2016, 'On the potential of uncertainty analysis for prediction of brake squeal propensity', Journal of Sound and Vibration, vol. 377, pp. 123-132.
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Zhao, J, Zhang, N & Ji, N 2016, 'Steady-state response of fluid-structure interactions in hydraulic piping system of passive interconnected suspensions', International Journal of Vehicle Design, vol. 72, no. 4, pp. 305-305.
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Copyright © 2016 Inderscience Enterprises Ltd. Pressure changes in the liquid-filled fluid circuit of a hydraulically interconnected suspension (HIS) system can induce vibrations of the whole pipeline and the associated structure, and hence become a source of structural noise which degrades ride comfort. This paper presents a numerical and experimental investigation into the vibration of the hydraulic piping system of a passive interconnected suspension. The transfer matrix method (TMM) is used to develop a mathematical model, which consists of various pipe sections, hose sections, concentrated masses, spring supports, elbows, damper valves, and accumulators. Laboratory experiments are performed on two liquid-filled piping systems. The measured steady-state responses of the hydraulic circuits are compared with those obtained from numerical simulations of the developed model. It is found that the developed model of the hydraulic system has a reasonable accuracy in the frequency range of interest, and thus can be employed to optimise the design of the hydraulic system.

Zhao, L, Ji, J, Liu, J, Wu, Q & Zhou, J 2016, 'Tracking task-space synchronization of networked Lagrangian systems with switching topology', NONLINEAR DYNAMICS, vol. 83, no. 3, pp. 1673-1685.
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Zhao, L-S, Zhou, W-H, Fatahi, B, Li, X-B & Yuen, K-V 2016, 'A dual beam model for geosynthetic-reinforced granular fill on an elastic foundation', Applied Mathematical Modelling, vol. 40, no. 21-22, pp. 9254-9268.
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In this study, a new dual beam model was proposed for a geosynthetic-reinforced granular fill with an upper pavement. This dual beam model was subjected to a uniform surcharge loading and resting on an elastic foundation which was simulated by a Pasternak model. The upper pavement was modeled by an Euler-Bernoulli beam while the geosynthetic reinforced granular fill was simulated by a reinforced Timoshenko beam. The explicit derivation process for the behavior of this dual beam-foundation system was presented and an exact solution was obtained. A two-dimensional finite element analysis and a Pasternak model for simulating the granular fill were carried out to validate the reliability of the proposed dual beam model. A parametric analysis was put forward to investigate the behavior of this dual beam-foundation system. It was found that the length of the pavement structure and vertical uniform loading, the stiffness and shear modulus of the foundation soil had significant influences on the behavior of the dual beam-foundation system.

Zhao, M & Ji, J 2016, 'Dynamic Analysis of Wind Turbine Gearbox Components', ENERGIES, vol. 9, no. 2.
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Zheng, C, Liu, H, Ding, X, Kouretzis, GP & Sheng, D 2016, 'Three-Dimensional Effects in Low-Strain Integrity Testing of Large Diameter Pipe Piles', Journal of Engineering Mechanics, vol. 142, no. 9, pp. 04016064-04016064.
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Zhou, A, Huang, R & Sheng, D 2016, 'Corrigendum: Capillary water retention curve and shear strength of unsaturated soils', Canadian Geotechnical Journal, vol. 53, no. 12, pp. 2086-2086.
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Zhou, A, Huang, R & Sheng, D 2016, 'Capillary water retention curve and shear strength of unsaturated soils', Canadian Geotechnical Journal, vol. 53, no. 6, pp. 974-987.
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This paper proposes a new water retention model for unsaturated soils, which takes into account capillary condensation of adsorbed water. In this model, the degree of saturation of a soil is separated into that based on capillary water and that based on adsorbed water. Through analysis of a partially saturated two-cylinder system, a new shear strength criterion for unsaturated soils is proposed, in which only the degree of saturation based on capillary water contributes to the variation of shear strength with suction. The proposed shear strength criterion is justified against thermodynamic principles and is compared against existing criteria in the literature, which shows that it provides a much improved prediction of the experimental data for a wide range of suction values.

Abdulle, A, Tan, AA, Pradhan, B & Abdullahi, S 1970, 'Temporal assessment on land use land cover of Somalia after the effect of the civil war using remote sensing', IOP Conference Series: Earth and Environmental Science, IOP Publishing, pp. 012063-012063.
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Adak, C, Chaudhuri, BB & Blumenstein, M 1970, 'Named Entity Recognition from Unstructured Handwritten Document Images', 2016 12th IAPR Workshop on Document Analysis Systems (DAS), 2016 12th IAPR Workshop on Document Analysis Systems (DAS), IEEE, Santorini, Greece, pp. 375-380.
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© 2016 IEEE.Named entity recognition is an important topic in the field of natural language processing, whereas in document image processing, such recognition is quite challenging without employing any linguistic knowledge. In this paper we propose an approach to detect named entities (NEs) directly from offline handwritten unstructured document images without explicit character/word recognition, and with very little aid from natural language and script rules. At the preprocessing stage, the document image is binarized, and then the text is segmented into words. The slant/skew/baseline corrections of the words are also performed. After preprocessing, the words are sent for NE recognition. We analyze the structural and positional characteristics of NEs and extract some relevant features from the word image. Then the BLSTM neural network is used for NE recognition. Our system also contains a post-processing stage to reduce the true NE rejection rate. The proposed approach produces encouraging results on both historical and modern document images, including those from an Australian archive, which are reported here for the very first time.

Adak, C, Chaudhuri, BB & Blumenstein, M 1970, 'Offline Cursive Bengali Word Recognition Using CNNs with a Recurrent Model', 2016 15th International Conference on Frontiers in Handwriting Recognition (ICFHR), 2016 15th International Conference on Frontiers in Handwriting Recognition (ICFHR), IEEE, Shenzhen, China, pp. 429-434.
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© 2016 IEEE. This paper deals with offline handwritten word recognition of a major Indic script: Bengali. Due to the structure of this script, the characters (mostly ortho-syllables) are frequently overlapping and hard to segment, especially when the writing is cursive. Individual character recognition and the combination of outputs can increase the likelihood of errors. Instead, a better approach can be sending the whole word to a suitable recognizer. Here we use the Convolutional Neural Network (CNN) integrated with a recurrent model for this purpose. Long short-term memory blocks are used as hidden units. Also, the CNN-derived features are employed in a recurrent model with a CTC (Connectionist Temporal Classification) layer to get the output. We have tested our method on three datasets: (a) a publicly available dataset, (b) a new dataset generated by our research group and (c) an unconstrained dataset. The dataset (a) contains 17,091 words, while our dataset (b) contains 107,550 number of words in total. In addition to these, the dataset (c) is comprised of 5,223 words. We have compared our results with those of some earlier work in the area and have found improved performance, which is due to the novel integration of CNNs with the recurrent model.

Adak, C, Chaudhuri, BB & Blumenstein, M 1970, 'Writer identification by training on one script but testing on another', 2016 23rd International Conference on Pattern Recognition (ICPR), 2016 23rd International Conference on Pattern Recognition (ICPR), IEEE, Mexico, pp. 1153-1158.
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© 2016 IEEE. This paper deals with identifying a writer from his/her offline handwriting. In a multilingual country where a writer can scribe in multiple scripts, writer identification becomes challenging when we have individual handwriting data in one script while we need to verify/identify a writer from handwriting in another script. In this paper such an issue is addressed with two scripts: English and Bengali. Here we model the task as a classification problem, where training data contains only Bengali handwritten samples and testing is performed on English handwritten texts. This work is based on the understanding that a writer has some inherent stroke characteristics that are independent of the script in which (s)he writes. In this work, some implicit structural and statistical features are extracted, and multiple classifiers are employed for writer identification. Many training sessions are run on a database of 100 writers and the performances are analyzed. We have obtained encouraging results on this database, which show the effectiveness of our method.

Alaei, A, Conte, D, Blumenstein, M & Raveaux, R 1970, 'Document Image Quality Assessment Based on Texture Similarity Index', 2016 12th IAPR Workshop on Document Analysis Systems (DAS), 2016 12th IAPR Workshop on Document Analysis Systems (DAS), IEEE, Santorini, Greece, pp. 132-137.
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© 2016 IEEE.In this paper, a full reference document image quality assessment (FR DIQA) method using texture features is proposed. Local binary patterns (LBP) as texture features are extracted at the local and global levels for each image. For each extracted LBP feature set, a similarity measure called the LBP similarity index (LBPSI) is computed. A weighting strategy is further proposed to improve the LBPSI obtained based on local LBP features. The LBPSIs computed for both local and global features are then combined to get the final LBPSI, which also provides the best performance for DIQA. To evaluate the proposed method, two different datasets were used. The first dataset is composed of document images, whereas the second one includes natural scene images. The mean human opinion scores (MHOS) were considered as ground truth for performance evaluation. The results obtained from the proposed LBPSI method indicate a significant improvement in automatically/accurately predicting image quality, especially on the document image-based dataset.

Alaei, F, Alaei, A, Blumenstein, M & Pal, U 1970, 'A brief review of document image retrieval methods: Recent advances', 2016 International Joint Conference on Neural Networks (IJCNN), 2016 International Joint Conference on Neural Networks (IJCNN), IEEE, Vancouver, CANADA, pp. 3500-3507.
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© 2016 IEEE.Due to the rapid increase of different digitized documents, the development of a system to automatically retrieve document images from a large collection of structured and unstructured document images is in high demand. Many techniques have been developed to provide an efficient and effective way for retrieving and organizing these document images in the literature. This paper provides an overview of the methods which have been applied for document image retrieval over recent years. It has been found that from a textual perspective, more attention has been paid to the feature extraction methods without using OCR.

Alaei, F, Alaei, A, Blumenstein, M & Pal, U 1970, 'Document image retrieval based on texture features and similarity fusion', 2016 International Conference on Image and Vision Computing New Zealand (IVCNZ), 2016 International Conference on Image and Vision Computing New Zealand (IVCNZ), IEEE, Palmerston North, New Zealand, pp. 1-6.
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© 2016 IEEE. In this paper we investigate the usefulness of two different texture features along with classification fusion for document image retrieval. A local binary texture method, as a statistical approach, and a wavelet analysis technique, as a transform-based approach, are used for feature extraction and two feature vectors are obtained for every document image. The similarity distances between each of the two feature vectors extracted for a given query and the feature vectors extracted from the document images in the training step are computed separately. In order to use the properties of both features, a classifier fusion technique is then employed using a weighted average fusion of distance measures obtained in relation to each feature vector. The document images are finally ranked based on the greatest visual similarity to the query obtained from the fusion similarity measures. The Media Team Document Database, which provides a great variety of page layouts and contents, is considered for evaluating the proposed method. The results obtained from the experiments demonstrate a correct document retrieval of 65.4% and 91.8% in the Top-1 and Top-10 ranked document list, respectively.

Alaei, F, Alaei, A, Pal, U & Blumenstein, M 1970, 'Document Image Retrieval Based on Texture Features: A Recognition-Free Approach', 2016 International Conference on Digital Image Computing: Techniques and Applications (DICTA), 2016 International Conference on Digital Image Computing: Techniques and Applications (DICTA), IEEE, Gold Coast, Australia, pp. 1-7.
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© 2016 IEEE.The tendency of current technology is towards a paperless world. Due to the rapid increase of digitized documents, providing a fast and easy method for retrieval is in high demand. The aim of this paper is to examine the effectiveness of texture features for document image retrieval. Thus, segmentation-free document image retrieval using a binary texture method is proposed. In the proposed approach, local features are extracted, local grey-level structures are summarised, and their distribution is characterised using global features. The assumption is that texture properties in the text regions and non-text regions of the document images are different. This assumption is used to rank the available document images and retrieve only those, which have greatest visual similarity to a given query. The under-sampled image and sub-images of the original image are further considered to improve the retrieval results, which are up to 76.0% in the first ranking and 96.2% in the Top-10 ranking. The Media Team Oulu Document Database, which is a heterogeneous database that offers a great variety of page layouts and contents, is used for experimentation.

Alamdari, MM, Khoa, NLD, Runcie, P, Li, J & Mustapha, S 1970, 'Characterization of gradually evolving structural deterioration in jack arch bridges using support vector machine', Maintenance, Monitoring, Safety, Risk and Resilience of Bridges and Bridge Networks - Proceedings of the 8th International Conference on Bridge Maintenance, Safety and Management, IABMAS 2016, pp. 2322-2327.
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The main objective of structural health monitoring is to provide reliable information about the health state of the critical structures by implementing a damage characterization strategy to detect the presence of damage, location, severity as possibly failure prediction as soon as the damage occurs. This paper presents a robust approach to detect and characterize a gradually evolving damage based on time responses data captured from a steel reinforced concrete structure. The presented method is in the context of unsupervised and nonmodel-based approaches, hence, there is no need for any representative numerical/finite element model of the structure to be built. In this work, we propose one-class support vector machine as an anomaly detection method. One-class support vector machine fits well for damage diagnosis in structural health monitoring since there may exist many damaged patterns and one-class support vector machine can detect all of them as anomalies. To demonstrate the feasibility of the method in the detection and assessment of a gradually evolving deterioration, a test bed was established to replicate a concrete jack arch which is a main structural component on the Sydney Harbour Bridge – one of Australia’s iconic structures. The structure is a concrete cantilever beam with an arch section which is located on the eastern side of the bridge underneath the bus lane. It is assumed that the structure is subjected to Gaussian white noise excitation. A crack is introduced in the structure using a cutting saw and its length is progressively increased in four stages while the depth was constant; these four damage cases correspond to less than 0.5% reduction in the first three modes of the structure. The damage identification results using the presented approach demonstrated the feasibility of applying support vector machine as a learning technique for damage characterization in structural health monitoring. The method accurately separated two states ...

Antonacopoulos, A, Gatos, B, Blumenstein, M, Lladós, J & Lopresti, D 1970, 'Message from the General Chairs and Program Chairs', 2016 12th IAPR Workshop on Document Analysis Systems (DAS), 2016 12th IAPR Workshop on Document Analysis Systems (DAS), IEEE, p. xi.
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Bakar, SBA, Pradhan, B, Lay, US & Abdullahi, S 1970, 'Spatial assessment of land surface temperature and land use/land cover in Langkawi Island', IOP Conference Series: Earth and Environmental Science, IOP Publishing, pp. 012064-012064.
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Chakraborty, A & Blumenstein, M 1970, 'Marginal Noise Reduction in Historical Handwritten Documents -- A Survey', 2016 12th IAPR Workshop on Document Analysis Systems (DAS), 2016 12th IAPR Workshop on Document Analysis Systems (DAS), IEEE, GREECE, pp. 323-328.
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© 2016 IEEE.This paper presents a survey on different approaches for removing the marginal noise from document images, and anlaysing the research challenges of those methods relating to handwritten historical datasets. In this survey, historical documents collected from Australian Archives and Libraries are introduced and the associated layout complexities of those document images are also described. Benchmarking other historical databases related to this work is also discussed. This survey discusses the difficulties and suitability of the state-of-the-art methods to remove marginal noise as well as preserving the text content from handwritten historical documents. This survey helps researchers to identify appropriate methods according to the associated marginal noise and also illustrates their drawbacks in order to make suggestions for developing approaches, which are more general and robust for any datasets.

Chakraborty, A & Blumenstein, M 1970, 'Preserving Text Content from Historical Handwritten Documents', 2016 12th IAPR Workshop on Document Analysis Systems (DAS), 2016 12th IAPR Workshop on Document Analysis Systems (DAS), IEEE, Santorini, Italy, pp. 329-334.
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© 2016 IEEE.We propose a holistic, dynamic method to preserve text content with zero tolerance while removing marginal noise for historical handwritten document images. The key idea is to identify and analyze the region between the sharp peak at the edge and page frame of the text content at each margin. Depending on the proximity of the sharp peak to the text, the text content is then extracted from the document image. This method automatically adapts thresholds for each single document image and is directly applicable to gray-scale images. The proposed method is evaluated on four diverse handwritten historical datasets: Queensland State Archive (QSA), Saint Gall, Parzival and the Prosecution Project. Experimental results show that the proposed method achieves higher accuracy compared with other methods tested on the Saint Gall and Parzival datasets, whilst for the other two Australian datasets, which have been introduced here for the first time, the results are very encouraging.

Cheema, P, Khoa, NLD, Makki Alamdari, M, Liu, W, Wang, Y, Chen, F & Runcie, P 1970, 'On Structural Health Monitoring Using Tensor Analysis and Support Vector Machine with Artificial Negative Data', Proceedings of the 25th ACM International on Conference on Information and Knowledge Management, CIKM'16: ACM Conference on Information and Knowledge Management, ACM, Indianapolis, Indiana, USA, pp. 1813-1822.
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© 2016 ACM. Structural health monitoring is a condition-based technology to monitor infrastructure using sensing systems. Since we usually only have data associated with the healthy state of a structure, one-class approaches arc more practical. However, tuning the parameters for one-class techniques (like one-class Support Vector Machines) still remains a relatively open and difficult problem. Moreover, in structural health monitoring, data arc usually multi-way, highly redundant and correlated, which a matrix-based two-way approach cannot capture all these relationships and correlations together. Tensor analysis allows us to analyse the multi-way vibration data at the same time. In our approach, we propose the use of tensor learning and support vector machines with artificial negative data generated by density estimation techniques for damage detection, localization and estimation in a one-class manner. The artificial negative data can help tuning SVM parameters and calibrating probabilistic outputs, which is not possible to do with one-class SVM. The proposed method shows promising results using data from laboratory-based structures and also with data collected from the Sydney Harbour Bridge, one of the most iconic structures in Australia. The method works better than the one-class approach and the approach without using tensor analysis.

Christensen, J, Rasmussen, J, Halkon, B & Koike, S 1970, 'The Development of a Methodology to Determine the Relationship in Grip Size and Pressure to Racket Head Speed in a Tennis Forehand Stroke', Procedia Engineering, 11th Conference of the International Sports Engineering Association (ISEA), Elsevier BV, Delft, NETHERLANDS, pp. 787-792.
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© 2016 The Authors. Published by Elsevier Ltd. This study developed a methodology to examine the effects of grip size and grip firmness on the kinematic contribution of angular velocity (KCAV) to the generation of racket head speed during a topspin tennis forehand. The KCAV is subdivided into kinematic contribution of joint angular velocity and kinematic contribution of the body segments in the upper trunk translational and angular velocities. Two Babolat Pure Storm GT rackets, with grip sizes 2 and 4 respectively, were used with Tekscan 9811E pressure sensors applied to the handles to examine pressure distribution during the stroke. Upper body kinematic data taken from the racket arm and trunk were obtained by means of a Vicon motion capture system. One elite male tennis player was recruited. Fifty topspin forehand strokes per grip at two nominal grip pressures were performed in a laboratory environment with balls being tossed towards the player and struck on the bounce towards a target on a net in as consistent a way as practically achievable. Processing of the results showed that the firm grip condition led to a significant (p<0.001) increase in average racket head speed compared to a normal grip condition. The normal gripping condition resulted in a significant (p<0.001) increase in average racket head speed for grip size 2 compared to grip size 4. A trend in negative linear relationships was found between upper trunk and shoulder joint in KCAV across conditions. Using the smaller grip also led to a trend in negative linear relationship between shoulder joint and wrist joint in KCAV across grip conditions. Grip pressure for grip size 2 showed the same pattern across gripping conditions. From 50-75% of completion in forward swing, the pressure difference due to grip firmness decreased. This feasibility study managed to quantify the KCAV while performing a topspin forehand, with respect to changing of grip size and grip pressure in an elite male tenni...

Dang, LC, Dang, CC, Khabbaz, H & Fatahi, B 1970, 'Numerical Assessment of Fibre Inclusion in a Load Transfer Platform for Pile-Supported Embankments over Soft Soil', Geo-China 2016, Fourth Geo-China International Conference, American Society of Civil Engineers, Shandong, China, pp. 148-155.
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© 2016 ASCE. This study presents the results of a numerical investigation in the performance of natural fibre reinforced load transfer platform (NFRLTP) for pile supported embankment construction over soft soil. A numerical analysis based on finite element method (FEM) was carried out on an NFRLTP pile-supported embankment in a two-dimensional plane strain condition. The effects of natural fibre inclusion in the load transfer platform on the stress transfer mechanism, generation and dissipation of excess pore water pressure have been analyzed and discussed in detail. The findings indicate that natural fibre reinforced soil as a load transfer platform facilitated the load transfer process from the embankment to piles, while decreases the intensity of load transferred to soft soil, the excess pore water pressure and the overall settlement.

Das, A, Mondal, P, Pal, U, Ferrer, MA & Blumenstein, M 1970, 'Fast and efficent multimodal eye biometrics using projective dictionary pair learning', 2016 IEEE Congress on Evolutionary Computation (CEC), 2016 IEEE Congress on Evolutionary Computation (CEC), IEEE, Vancouver, Canada, pp. 1402-1408.
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© 2016 IEEE.This work proposes a projective pairwise dictionary learning-based approach for fast and efficient multimodal eye biometrics. The work uses a faster Projective pairwise Discriminative Dictionary Learning (DL) in contrast to the traditional DL which uses synthesis DL. Projective Pairwise Discriminative Dictionary (PPDD) uses a synthesis dictionary and an analysis dictionary jointly to achieve the goal of pattern representation and discrimination. As the PPDD process of DL is in contrast to the use of l0 or l1-norm sparsity constraints on the representation coefficients adopted in most traditional DL, it works faster than other DL. Moreover, the blending of synthesis dictionary and an analysis dictionary also enhance the feature representation of the complex eye patterns. We employed the combination of sclera and iris traits to establish multimodal biometrics. The experimental study and analysis conducted fulfill the hypothesis we considered. In this work we employed a part of the UBIRIS version 1 dataset to conduct the experiments.

Das, A, Pal, U, Ferrer, MA & Blumenstein, M 1970, 'SSRBC 2016: Sclera Segmentation and Recognition Benchmarking Competition', 2016 International Conference on Biometrics (ICB), 2016 International Conference on Biometrics (ICB), IEEE, Halmstad, Sweden.
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© 2016 IEEE.This article reports and summarizes the results of a competition on sclera segmentation and recognition benchmarking, called Sclera Segmentation and Recognition Benchmarking Competition 2016 (SSRBC 2016). It was organized in the context of the 9th IAPR International Conference on Biometrics (ICB 2016). The goal of this competition was to record the recent developments in sclera segmentation and recognition, and also to gain the attention of researchers on this subject of biometrics. In this regard, we have used a multi-angle sclera dataset (MASD version 1). It is comprised of 2624 images taken from both the eyes of 82 identities. Therefore, it consists of images of 164 (82∗2) different eyes. We have prepared a manual segmentation mask of these images to create the baseline for both tasks. We have, furthermore, adopted precision and recall based statistical measures to evaluate the effectiveness of the segmentation and the ranks of the competing algorithms. The recognition accuracy measure has been employed to measure the recognition task. To summarize, twelve participants registered for the competition, and among them, three participants submitted their algorithms/ systems for the segmentation task and two their recognition algorithm. The results produced by these algorithms reflect developments in the literature of sclera segmentation and recognition, employing cutting edge segmentation techniques. Along with the algorithms of three competing teams and their results, the MASD version 1 dataset will also be freely available for research purposes from the organizer's website. The competition also demonstrates the recent interests of researchers from academia as well as industry on this subject of biometrics.

Fan, X, Li, B, Wang, Y, Wang, Y & Chen, F 1970, 'The ostomachion process', 30th AAAI Conference on Artificial Intelligence, AAAI 2016, 30th Association-for-the-Advancement-of-Artificial-Intelligence (AAAI) Conference on Artificial Intelligence, ASSOC ADVANCEMENT ARTIFICIAL INTELLIGENCE, Phoenix, AZ, pp. 1547-1553.
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Stochastic partition processes for exchangeable graphs produce axis-Aligned blocks on a product space. In relational modeling, the resulting blocks uncover the underlying interactions between two sets of entities of the relational data. Although some flexible axis-Aligned partition processes, such as the Mondrian process, have been able to capture complex interacting patterns in a hierarchical fashion, they are still in short of capturing dependence between dimensions. To overcome this limitation, we propose the Ostomachion process (OP), which relaxes the cutting direction by allowing for oblique cuts. The partitions generated by an OP are convex polygons that can capture inter-dimensional dependence. The OP also exhibits interesting properties: 1) Along the time line the cutting times can be characterized by a homogeneous Poisson process, and 2) on the partition space the areas of the resulting components comply with a Dirichlet distribution. We can thus control the expected number of cuts and the expected areas of components through hyper-parameters. We adapt the reversible-jump MCMC algorithm for inferring OP partition structures. The experimental results on relational modeling and decision tree classification have validated the merit of the OP.

Ghanavati, M, Wong, RK, Chen, F, Wang, Y & Fong, S 1970, 'A Generic Service Framework for Stock Market Prediction', 2016 IEEE International Conference on Services Computing (SCC), 2016 IEEE International Conference on Services Computing (SCC), IEEE, San Francisco, CA, pp. 283-290.
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Ghanavati, M, Wong, RK, Chen, F, Wang, Y & Fong, S 1970, 'Effective Local Metric Learning for Water Pipe Assessment', ADVANCES IN KNOWLEDGE DISCOVERY AND DATA MINING, PAKDD 2016, PT I, 20th Pacific-Asia Conference on Knowledge Discovery and Data Mining (PAKDD), Springer International Publishing, Univ Auckland, Auckland, NEW ZEALAND, pp. 565-577.
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Ghobadi, Y, Pradhan, B & Kabiri, K 1970, 'Spatio-Temporal Relationship Between Surface Temperature and NDVI Using Remotely Sensed data', 41st COSPAR Scientific Assembly, abstracts from the meeting that was to be held 30 July-7 August at the Istanbul Congress Center (ICC), Turkey, but was cancelled. See http://cospar2016. tubitak. gov. tr/en/, Abstract A3. 1-39-16..

Ghosh, B, Fatahi, B, Khabbaz, H & Hsi, J 1970, 'Reinforced Timoshenko Beam Theory to Simulate Load Transfer Mechanism in CMC Supported Embankments', Proceedings of 12th Australia New Zealand Conference on Geomechanics, Australia New Zealand Geomechanics conference, Australian Geomechanics Society, Wellington, New Zealand, pp. 1099-1106.
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Controlled modulus column (CMC) supported embankments are increasingly being used for construction of major highway embankments on soft ground particularly near waterways or coastal regions. CMCs are sustainable and cost-effective ground improvement technology that transmit the load from the traffic and the embankment to a lower bearing stratum through a composite CMC/soil matrix. The key influencing components of the load transfer mechanism include embankment fill, load transfer platform (LTP) with one or more layers of geosynthetics, CMC and the foundation soils. Rapid growth of the application of geosynthetics between two granular layers in the column supported embankment has been observed in the last two decades. The use of LTP enhances the load transfer mechanism in the CMC improved soft ground and minimises the post construction settlement of the ground. In this paper, reinforced Timoshenko beam theory is adopted to simulate the LTP with one layer of geosynthetics that is resting on elastic foundation with columns. A parametric study is conducted to investigate the importance of the LTP on the load transfer mechanism for the CMC supported embankment. Special attentions are given to the thickness of the LTP, the use of geosynthetics and its influence on deflection of the LTP, the shear force developed in the LTP and the tension developed in geosynthetics. The parametric study reveals that the thickness of the LTP has a significant effect on the behaviour of LTP up to a certain limit.

Ghosh, B, Fatahi, B, Khabbaz, H & Kamruzzaman, AHM 1970, 'Analysis of CMC-Supported Embankments Considering Soil Arching', IN SITU AND LABORATORY TEST METHODS FOR SITE CHARACTERIZATION, DESIGN, AND QUALITY CONTROL, GeoChina International Conference, American Society of Civil Engineers, Jinan, Shandong, China, pp. 286-293.
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© ASCE. In this paper, the behaviour of geosynthetic-reinforced controlled modulus column-supported embankments is studied for different distributions of loadings induced by arching on the load transfer platform (LTP). This study proposes a mechanical model for idealising the response of LTP-soft soil-column system, by representing each sub-system using commonly used mechanical elements such as rough-elastic membrane, beam, and spring. The soil arching effect is incorporated in the model to determine the deflection of the soft soil as well as mobilised tension in the geosynthetics more accurately. The effects of the column stiffness and consolidation of saturated soft soils are also incorporated in the model. Moment and shear force in the LTP, tension developed in the geosynthetics, and settlements of the improved soft ground are predicted using the proposed model. To evaluate the proposed model, a parametric study is conducted to investigate the influence of different pressure distribution due to different arching theories. It is observed that the pattern of distribution of the arching loads affect the performance of controlled modulus column-supported embankments significantly.

Halkon, B & Rothberg, S 1970, 'Correction of laser Doppler vibrometry measurements affected by steering mirror vibration', OPTICAL MEASUREMENT TECHNIQUES FOR STRUCTURES & SYSTEMS III, 6th International Conference on Optical Measurement Techniques for Structures and Systems III (OPTIMESS2015), SHAKER PUBLISHING BV, Univ Antwerp, Antwerp, BELGIUM, pp. 117-126.

Halkon, BJ & Rothberg, SJ 1970, 'A practical guide to laser Doppler vibrometry measurements directly from rotating surfaces', IMechE Vibrations in Rotating Machinery, IMechE Vibrations in Rotating Machinery, University of Manchester, UK.

Hashim, MS, Saip, SN, Hani, N, Pradhan, B & Abdullahi, S 1970, 'Accuracy assessment of NOGGIN Plus and MALÅ RAMAC X3M single channel ground penetrating RADAR (GPR) for underground utility mapping', IOP Conference Series: Earth and Environmental Science, IOP Publishing, pp. 012025-012025.
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Indraratna, B, Rujikiatkamjorn, C & Zhong, R 1970, 'Recent Developments of Vacuum-Assisted Consolidation of Soft Estuarine Clays', Geotechnical and Structural Engineering Congress 2016, Geotechnical and Structural Engineering Congress 2016, American Society of Civil Engineers, pp. 950-959.
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© ASCE. For vacuum-Assisted ground improvement on highly compressible alluvial or marine deposits, the application of suction pressure accelerates consolidation and controls lateral deformation by isotropically increasing the effective stress. Analytical, numerical, and experimental research on vacuum-Assisted prefabricated vertical drains (PVDs) has been conducted at University of Wollongong in past 15 years. Key factors such as vacuum distribution, extent of smear, occurrence of non-Darcian flow, and large-strain effects have been studied and their implications are presented in the paper. Some practical approaches have been proposed to facilitate industrial design schemes for vacuum consolidation. 2D plane strain conversion approach has been proposed for numerical modeling of large soft area treated with multiple PVDs. The behavior of vacuum stabilized soil in the field has been predicted by the numerical models applied to selected case studies through fully-instrumented field trials, by measuring settlement, lateral movement and excess pore water pressure data. A good agreement between the predicted and field data was achieved. Some key theoretical and numerical approaches are presented in this paper, together with the case study involving the Ballina Bypass in Australia.

Indraratna, B, Rujikiatkamjorn, C, Zhong, R & Nguyen, T 1970, 'Drain and vacuum for soft soil stabilisation- Recent advances in experimental and numerical modelling', Proceedings of the 3rd International Conference GEOTEC on 'Geotechnics for Sustainable Infrastructure Development', Hanoi.

Israr, J, Indraratna, B & Rujikiatkamjorn, C 1970, 'Experimental Investigation into Internal Erosion Potential for Granular Filters', Proceedings of 13th Baltic Sea Geotechnical Conference, The 13th Baltic Sea Region Geotechnical Conference, Vilnius Gediminas Technical University, Vilnius, LITHUANIA, pp. 248-253.
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Internal erosion is a phenomenon whereby the filtrates under the influence of significant seepage forces accompany the finer fraction from potential internally unstable filters (e.g. broadly- and gap-graded soil), occasionally rendering them ineffective. The filter assessment for internal erosion or instability potential is emphasized through particle size distribution based geometrical criteria ignoring the effect of compaction. In this study, the results of hydraulic gradient controlled internal erosion tests conducted over a wide range of compacted sand-gravel mixtures were used to analyse some of the available geometrical criteria, which interestingly showed partial success in assessing the filter’s internal erosion potential. It was revealed that the occurrence of internal erosion is a combined function of particle size distribution and the relative density of soils that had been ignored in many of the existing criteria. A comparison between the assessments obtained from some of the particle size based criteria and that from a constriction size based technique was reported for a large body of published data. It was observed that the latter criterion, which incorporates the effects of both particle size distribution and relative density of soils in tandem, could assess the reported test results with higher accuracy.

Khare, V, Shivakumara, P, Kumar, A, Chan, CS, Lu, T & Blumenstien, M 1970, 'A quad tree based method for blurred and non-blurred video text frames classification through quality metrics', 2016 23rd International Conference on Pattern Recognition (ICPR), 2016 23rd International Conference on Pattern Recognition (ICPR), IEEE, Cancun, Mexico, pp. 4023-4028.
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Blur is a common artifact in video, which adds more complexity to text detection and recognition. To achieve good accuracies for text detection and recognition, this paper suggests a new method for classifying blurred and non-blurred frames in video. We explore quality metrics, namely, BRISQUE, NRIQA, GPC and SI, in a new way for classification. We estimate the values of these metrics with the help of predefined samples called reference values. To widen the difference between metric values for better classification, we introduce scaling factors as a non-linear sigmoidal function, which considers the metric of each current frame and its reference and results in templates. Based on the characteristics of metrics, the proposed method finds a relationship between the metrics to derive rules for classification. To classify the frame containing local blur, we explore quad tree division with classification rules which divide non-blurred blocks to identify local blur. We use standard databases, namely, ICDAR 2013, ICDAR 2015 and YVT videos for experimentation, and evaluate the proposed method in terms of text detection and recognition rates given by text detection and binarization methods before and after classification.

Lin, P, Zhang, B, Guo, T, Wang, Y & Chen, F 1970, 'Infinite Hidden Semi-Markov modulated interaction point process', Advances in Neural Information Processing Systems, pp. 3907-3915.
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The correlation between events is ubiquitous and important for temporal events modelling. In many cases, the correlation exists between not only events' emitted observations, but also their arrival times. State space models (e.g., hidden Markov model) and stochastic interaction point process models (e.g., Hawkes process) have been studied extensively yet separately for the two types of correlations in the past. In this paper, we propose a Bayesian nonparametric approach that considers both types of correlations via unifying and generalizing the hidden semi-Markov model and interaction point process model. The proposed approach can simultaneously model both the observations and arrival times of temporal events, and automatically determine the number of latent states from data. A Metropolis-within-particle-Gibbs sampler with ancestor resampling is developed for efficient posterior inference. The approach is tested on both synthetic and real-world data with promising outcomes.

Lin, P, Zhang, B, Guo, T, Wang, Y & Chen, F 1970, 'Interaction point processes via infinite branching model', 30th AAAI Conference on Artificial Intelligence, AAAI 2016, 30th Association-for-the-Advancement-of-Artificial-Intelligence (AAAI) Conference on Artificial Intelligence, ASSOC ADVANCEMENT ARTIFICIAL INTELLIGENCE, Phoenix, AZ, pp. 1853-1859.
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Many natural and social phenomena can be modeled by interaction point processes (IPPs) (Diggle et al. 1994), stochastic point processes considering the interaction between points. In this paper, we propose the infinite branching model (IBM), a Bayesian statistical model that can generalize and extend some popular IPPs, e.g., Hawkes process (Hawkes 1971; Hawkes and Oakes 1974). It treats IPP as a mixture of basis point processes with the aid of a distance dependent prior over branching structure that describes the relationship between points. The IBM can estimate point event intensity, interaction mechanism and branching structure simultaneously. A generic Metropolis-within-Gibbs sampling method is also developed for model parameter inference. The experiments on synthetic and real-world data demonstrate the superiority of the IBM.

Mahdavi, H, Fatahi, B, Khabbaz, H, Krzeminski, M, Santos, R & Marix-Evans, M 1970, 'Three-Dimensional Simulation of a Load Transfer Mechanism for Frictional and End Bearing CMC Supported Embankments on Soft Soil', Geo-China 2016, Fourth Geo-China International Conference, American Society of Civil Engineers, Shandong, China, pp. 60-67.
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© ASCE. Recently, the use of controlled modulus columns (CMC) has gained popularity in the support of rail and road bridge approach embankments on soft soils. If the columns are extended into a competent firm soil, and designed to take nearly all the vertical loads, they become rigid inclusions. The advantage of this design approach is that settlement will be controlled, but the drawback is that the columns will attract greater load, including bending moment and shear force in situations where non-uniform loading or ground conditions exist. The load on the composite soil-CMC is uniformly distributed by the upper layer of granular load transfer platform (LTP). In this paper, the effect of CMC length on the load transfer mechanism is numerically investigated. Coupled flow-deformation analysis has been performed for a long period to understand the system response in the long term, while interface elements capable of simulating gapping and sliding between CMC and the surrounding soil are considered. A geosynthetic reinforcement layer has been simulated using the inbuilt FLAC3D geogrid element. The force in the reinforcement layer has been evaluated, and in particular, a clear comparison is made between the stresses in CMC and the ground settlement with floating and end-bearing columns.

Makki Alamdari, M, Khoa, NLD, Runcie, P, Li, J & Mustapha, S 1970, 'Characterization of gradually evolving structural deterioration in jack arch bridges using support vector machine', MAINTENANCE, MONITORING, SAFETY, RISK AND RESILIENCE OF BRIDGES AND BRIDGE NETWORKS, 8th International Conference on Bridge Maintenance, Safety and Management (IABMAS), CRC Press, Foz do Iguacu, BRAZIL, pp. 555-555.
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Manafizad, AN, Pradhan, B & Abdullahi, S 1970, 'Estimation of Peak Ground Acceleration (PGA) for Peninsular Malaysia using geospatial approach', IOP Conference Series: Earth and Environmental Science, IOP Publishing, pp. 012069-012069.
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Nampak, H & Pradhan, B 1970, 'Use of multi-temporal SPOT-5 satellite images for land degradation assessment in Cameron Highlands, Malaysia using Geospatial techniques', 41st COSPAR Scientific Assembly, abstracts from the meeting that was to be held 30 July-7 August at the Istanbul Congress Center (ICC), Turkey, but was cancelled. See http://cospar2016. tubitak. gov. tr/en/, Abstract A3. 1-13-16..

Ngo, NT & Tung, TM 1970, 'Coupled Discrete-Continuum Method for Studying Load-Deformation of a Stone Column Reinforces Rail Track Embankments', Procedia Engineering, International Conference on Sustainable Development of Civil, Urban and Transportation Engineering (CUTE), Elsevier BV, Ho Chi Minh City, VIETNAM, pp. 139-145.
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Stone columns are being increasingly used as a cost-effective and environmentally friendly method for reinforcing soft soils of rail track embankments. Deformation behavior of stone columns reinforced soft clay has been the subject of an extensive number of experimental and modelling studies during last decades. A continuum-based numerical method provides valuable insights into the settlement, lateral deformation, stress and strain-rate dependent behavior of stone column at macroscopic scale. However, due to the discrete nature of stone columns, which are comprised of granular aggregates, they cannot be properly modelled by the continuum methods. This paper presents a novel coupling model of discrete element method (DEM) and finite difference method (FDM) to investigate the load-deformation behavior of stone columns considering micromechanical analysis. In the coupled discrete-continuum model, the soft soil domain under track embankment is modelled by the continuum method using FLAC and stone column is modelled by the discrete element method using PFC2D. A force-displacement transmission mechanism is introduced to achieve the interaction of both domains in which the DEM transfers forces and moment to the FDM and then the FDM updates displacements back to the DEM. The predicted load-deformation results are in good agreement with the data measured experimentally; indicating that the proposed coupling discrete-continuum model could capture the deformation behavior of stone column reinforced soft soils.

Ngo, NT, Indraratna, B & Rujikiatkamjorn, C 1970, 'Load-Deformation Behavior of a Stone Column Using the Coupled DEM-FDM Method', Geotechnical and Structural Engineering Congress 2016, Geotechnical and Structural Engineering Congress 2016, American Society of Civil Engineers, pp. 1618-1626.
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This paper presents a novel coupled model of discrete element method (DEM) and finite difference method (FDM) to investigate the load-deformation of stone columns reinforced soft clay. In the proposed model, the soft clay domain was modelled by the continuum method using FLAC and stone column was modelled by the discrete element method using PFC2D. Algorithms and mathematical framework to assist coupling between the two domains were introduced, in which the DEM transfers forces and moment to the FDM and then the FDM provides an update of displacements to the DEM. The predicted load-deformation responses obtained from the coupling model reasonably agreed well with data measured experimentally, indicating that the proposed coupling discrete-continuum model could capture the deformation behavior of stone column stabilized soft clay. Evolutions of contact force distributions developed in stone column at varying levels of settlement were presented. Shear stress-strain contours induced in the surrounding soft soils were also investigated.

Ngo, NT, Indraratna, B & Rujikiatkamjorn, C 1970, 'Study on the Interface Behavior of a Geosynthetics-Reinforced Fouled Ballast Using the Discrete Element Method', Geo-Chicago 2016, Geo-Chicago 2016, American Society of Civil Engineers, pp. 730-738.
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Railways offer an efficient and economic transport mode in many parts of the developed countries including Australia, China and USA. Ballast layer is designed as a load bearing layer for rail tracks and to be free draining, but when the ballast voids are wholly or partially impeded due to the intrusion of fine particles, the ballast can be considered to be fouled. Fouling causes a reduction in the drainage capacity of ballast, thereby reducing the track resiliency and triggering high maintenance costs. Geosynthetics are commonly used in railway construction for reinforcement and stabilization purposes. When railway ballast becomes fouled the beneficial effect of the geosynthetics could decrease significantly. This paper presents a study of how the interface behavior of geosynthetics-ballast copes with fouling using discrete element modelling (DEM) of large-scale direct shear tests. A series of large-scale direct shear tests for coal fouled ballast were carried out in the laboratory and were then simulated in the DEM. Shear stress-strain and volumetric dilation responses obtained from the DEM simulations were in reasonable agreement with those measured experimentally. The contact force distributions of fresh and fouled ballast were captured and shown that the fouled ballast exhibited higher number of contact forces compared to the fresh ballast assembly. This is due to coal fines accumulated in voids among large particles then partially carry and transmit contact forces across the assembly. Strains developed horizontally across the geogrid were also analyzed in this study.

Nguyen, L, Fatahi, B & Khabbaz, H 1970, 'A Novel Model to Simulate the Behaviour of Cement-Treated Clay under Compression and Shear', Geo-China 2016, Fourth Geo-China International Conference, American Society of Civil Engineers, Shandong, China, pp. 152-158.
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© ASCE. Soft clay treated with cement shows an improvement on strength due to the chemical interaction between cement and clay particles. Laboratory results showed that the peak strength of the cement treated clay reduces as the mean effective stress increases due to the effect of cementation degradation. Therefore, in this paper, a constitutive model was developed to simulate the behaviour of cement treated clay. Based on the critical state soil mechanics, the model proposed the non-linear failure envelope for the cement treated clay to merge with the critical state line (CSL) of the un-reinforced clay when the reinforced samples reach a sufficiently high stress levels. Moreover, a modified mean effective stress was proposed to include the contribution of cementation and its cementation degradation. Furthermore, the proposed model was evaluated by comparing the proposed model predictions against the Singapore clay treated with 10% cement available from the literature. The validation suggested that the proposed model can be used to predict the behaviour of cement treated clay very well.

Nguyen, QV, Fatahi, B & Hokmabadi, AS 1970, 'Influence of Shallow Foundation Characteristics on the Seismic Response of Mid-Rise Buildings Subjected to Strong Earthquakes', Geotechnical Special Publication, GeoChina International Conference, American Society of Civil Engineers, Shandong, China, pp. 117-124.
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Performance based seismic design is a modern approach to earthquake-resistant design shifting emphasis from 'strength' to 'performance'. In this study, the influence of the shallow foundation (footing) size on the seismic performance of the buildings subjected to strong earthquakes is investigated considering soil-structure interaction (SSI). A fifteen storey moment resisting frame sitting on shallow foundation over soft soil with different foundation size is simulated numerically using ABAQUS software. The developed three dimensional numerical simulation accounts for nonlinear behaviour of the soil medium by considering the variation of soil stiffness and damping as a function of developed shear strain in the soil elements during earthquake. Elastic-perfectly plastic model is adopted to simulate foundations and structural elements. Four strong earthquake records, including El Centro 1940, Hachinohe 1968, Northridge 1994, and Kobe 1995 have been taken as input accelerations for time history analysis in time domain. Due to natural period lengthening, there was a significant reduction in the base shears when the size of the foundation was reduced. It can be concluded that the foundation size can influence the dynamic characteristics and seismic response of the building due to SSI and should therefore be given careful consideration in order to ensure a safe and cost effective seismic design.

Nguyen, T, Indraratna, B & Rujikiatkamjorn, C 1970, 'Natural prefabricated vertical drain-Structure and Geohydraulic properties', In Proceedings of the 3rd International Conference on 'Geotechnics for Sustainable Infrastructure Development (GEOTEC), Hanoi.

Nguyen, TT, Indraratna, B & Rujikiatkamjorn, C 1970, 'An analytical evaluation of radial consolidation with respect to drain degradation', International Conference on Geotechnique, Construction Materials and Environment, Bangkok, Thailand, pp. 156-161.
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The use of synthetic prefabricated vertical drains over the past decades for soil improvement has had a negative ecological effect on the natural environment due to their long-term existence in soil. The emergence in recent years of Natural Fibre Drains (NFDs) made from biodegradable materials such as jute, coir, and straw isbelieved to be an environmentally friendly approach to treating soft soil. However, when subjected to adverseconditions such as pyritic acidic and/or biologically active soil, natural fibres can decay rapidly, and that resultsin a significant deterioration of the engineering characteristics of drains during consolidation. This deterioration can particularly reduce the discharge capacity of the drains, which retards the dissipation of excess pore pressure and delays consolidation. This paper represents an analytical method which can capture the effect that drain degradation has on the radial consolidation of soil over time, and then applies this method to an exponential reduction of drain discharge capacity. This analytical method, with supporting evidence from experimental data, reveals that there is a significant retardation in excess pore pressure dissipation due to drain degradation. The study indicates there is a potential risk when using NFDs in adverse soils and suggests that caution is needed in practice.

Nimbalkar, S & Indraratna, B 1970, 'In-situ performance assessment of ballasted railway track stabilised using geosynthetics and shock mats', Proceedings of the 5th International Conference on Geotechnical and Geophysical Site Characterisation, ISC 2016, International Conference on Geotechnical and Geophysical Site Characterisation, Australian Geomachanics Society, Gold Coast, pp. 1411-1416.
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In Australia, ballasted railway tracks are one of major modes of transportation. The main objectives of Australian railways are to cater for the demands of the supply chain in the mining and agriculture sectors, as well as to provide quicker and cost effective commuter transport in urban areas. However several geotechnical problems in the populated coastal areas pose significant issues. Ballasted tracks are conventionally constructed on compacted granular embankments overlying the natural subsoil. The granular embankments comprises of ballast and capping layers which undergo substantial deformations and degradation under the heavy cyclic loading of passenger and freight trains. This in turn, may lead to a loss of track geometry, and require costly frequent maintenance. In order to rectify these issues, appropriate stabilization techniques for ballast and capping are necessary, the extent of which depends also on the type of subgrade. When appropriately designed and installed, synthetic inclusions such as geosynthetics and/or shock mats can provide a cost effective alternatives to traditional techniques of ground improvement. Comprehensive field trials were carried out on two railway networks in Bulli and Singleton in New South Wales, Australia. In these studies, several track sections were instrumented with precise sensors for real-time monitoring of stress-deformation response of granular embankments. Different types of geosynthetics were placed beneath the ballast embankment. Recoverable and irrecoverable components of vertical deformations of the track substructure were routinely monitored. The amount of ballast breakage was evaluated by collecting samples from the field and by performing sieve analysis in the laboratory. It was evident that geosynthetics in the form of geogrids can decrease the vertical strains of the ballast layer, resulting in reduced maintenance costs. This paper describes the comprehensive field instrumentation, site geology, co...

Oberst, S, Zhang, Z, Campbell, G, Morlock, M, Lai, JCS & Hoffmann, N 1970, 'Towards the understanding of hip squeak in total hip arthroplasty using analytical contact models with uncertainty', Proceedings of the INTER-NOISE 2016 - 45th International Congress and Exposition on Noise Control Engineering: Towards a Quieter Future, Internoise Congress, http://pub.dega-akustik.de/IN2016/data/index.html, Hamburg, Germany, pp. 5539-5549.
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Osteoarthritis in hip joints affects patients' quality of life such that often only costly orthopaedic surgeries i.e. total hip arthroplasty (THA) provide relief. Common implant materials are metal alloys, steel or titanium-based, plastics such as ultra-high molecular weight polyethylene, or biocompatible alumina and composite ceramics. Hard-on-hard (HoH) bearing articulations, i.e. ceramic-on-ceramic, or hard-on-soft combinations are used. HoH implants have been known to suffer from squeaking, a phenomenon commonly encountered in friction-induced self-excited vibrations. However, the frictional contact mechanics, its dynamics related to impingement, the effect of socket position, stem configuration, bearing size and patient characteristics are poorly understood. This study gives an overview of the state of the art biomechanical research related to squeaking in THA, with a focus on the effects of friction, stability, related wear and lubrication. An analytical model is proposed to study the onset of friction-induced vibrations in a simplified hemispherical hip stem rubbing in its bearing by varying the contact area. Preliminary results of the complex eigenvalue analysis and stick-slip motion analysis indicate that an increased contact fosters the development of instabilities, even at very small values of the friction coefficient owing to large local contact pressures.

Oldham, KM, Chung, PWH, Edirisinghe, EA & Halkon, BJ 1970, 'Table tennis and computer vision: a monocular event classifier', Advances in Intelligent Systems and Computing, 10th International Symposium on Computer Science in Sports (ISCSS), Springer International Publishing, Loughborough, ENGLAND, pp. 29-32.
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© Springer International Publishing Switzerland 2016. Detecting events in table tennis using monocular video sequences for match-play officiating is challenging. Here a low-cost monocular video installation generates image sequences and, using the Horn-Schunck Optical Flow algorithm, ball detection and location processing captures sudden changes in the ball’s motion. It is demonstrated that each abrupt change corresponds to a distinct event pattern described by its combined velocity, acceleration and bearing. Component motion threshold values are determined from the analysis of a range of table tennis event video sequences. The novel event classifier reviews change in motion data against these thresholds, for use in a rules based officiating decision support system. Experimental results using this method demonstrate an event classification success rate of 95.9%.

Pal, S, Alaei, A, Pal, U & Blumenstein, M 1970, 'Performance of an Off-Line Signature Verification Method Based on Texture Features on a Large Indic-Script Signature Dataset', 2016 12th IAPR Workshop on Document Analysis Systems (DAS), 2016 12th IAPR Workshop on Document Analysis Systems (DAS), IEEE, Santorini, Italy, pp. 72-77.
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© 2016 IEEE. In this paper, a signature verification method based on texture features involving off-line signatures written in two different Indian scripts is proposed. Both Local Binary Patterns (LBP) and Uniform Local Binary Patterns (ULBP), as powerful texture feature extraction techniques, are used for characterizing off-line signatures. The Nearest Neighbour (NN) technique is considered as the similarity metric for signature verification in the proposed method. To evaluate the proposed verification approach, a large Bangla and Hindi off-line signature dataset (BHSig260) comprising 6240 (260×24) genuine signatures and 7800 (260×30) skilled forgeries was introduced and further used for experimentation. We further used the GPDS-100 signature dataset for a comparison. The experiments were conducted, and the verification accuracies were separately computed for the LBP and ULBP texture features. There were no remarkable changes in the results obtained applying the LBP and ULBP features for verification when the BHSig260 and GPDS-100 signature datasets were used for experimentation.

Pathirage, U & Indraratna, B 1970, 'A Permeable Reactive Barrier Installed in Acid Sulfate Soil Terrain', Geo-Chicago 2016, Geo-Chicago 2016, American Society of Civil Engineers, Chicago, IL, pp. 319-328.
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Pradhan, B 1970, 'A novel flood detection mapping using multi-temporal RADARSAT-2 and TerraSAR-X images through an optimized Taguchi based classification technique', 41st COSPAR Scientific Assembly, abstracts from the meeting that was to be held 30 July-7 August at the Istanbul Congress Center (ICC), Turkey, but was cancelled. See http://cospar2016. tubitak. gov. tr/en/, Abstract A3. 1-33-16..

Pradhan, B & Jena, R 1970, 'Spatial relationship between earthquakes, hot-springs and faults in Odisha, India', IOP Conference Series: Earth and Environmental Science, IOP Publishing, pp. 012070-012070.
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Rujikiatkamjorn, C, Perera, D & Indraratna, B 1970, 'Assessing Soil Disturbance while Installing Vertical Drains', Geotechnical and Structural Engineering Congress 2016, Geotechnical and Structural Engineering Congress 2016, American Society of Civil Engineers, pp. 971-981.
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© ASCE. Soil disturbance (smear zone) can be created while installing vertical drains, within which changes in horizontal permeability and the compressibility of in-situ soil can be observed. Previous studies on different aspects of soil disturbance due to driving vertical drains are limited, so extensive soil characterisation was carried out while installing drains at Ballina, NSW to obtain a more realistic smear zone. Soil disturbance was evaluated by determining the change in the coefficient of permeability, the water content, and volume compressibility away from the drain. The characteristics of the smear zone were compared to the data available from past literatures and indicated that the radius of the smear zone was about 6.3 times the equivalent mandrel radius, which was larger than that observed in the laboratory using reconstituted specimens.

Sameen, MI & Pradhan, B 1970, 'A novel built-up spectral index developed by using multiobjective particle-swarm-optimization technique', IOP Conference Series: Earth and Environmental Science, IOP Publishing, pp. 012006-012006.
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Sameen, MI & Pradhan, B 1970, 'Forecasting severity of traffic accidents using road geometry extracted from mobile laser scanning data', 37th Asian Conference on Remote Sensing, ACRS 2016, Sri Lanka, Colombo, pp. 1357-1362.
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This study analyzed the effects of road geometric elements such as horizontal curvature, superelevation, grade change, and design speed on accident severity. A semi-automatic method is proposed to extract aforementioned geometric elements from mobile laser scanning point clouds. Then a logistic regression model is used to establish relationships between road geometric elements and accident severity. Based on the coefficients calculated by the logistic regression model, the effects of each road geometric element on accident severity are discussed. Results showed that the average superelevation was the most contributed factor to serious injuries, grade change factor was the most critical factor for minor injuries and the damage only of accident severity levels. The analysis revealed that improving superelevations on horizontal curves should be considered by the safety agencies in Malaysia. In addition, design of vertical curves of expressways is also should be imp-roved.

Saqib, M, Daud Khan, S & Blumenstein, M 1970, 'Texture-based feature mining for crowd density estimation: A study', 2016 International Conference on Image and Vision Computing New Zealand (IVCNZ), 2016 International Conference on Image and Vision Computing New Zealand (IVCNZ), IEEE, Palmerston North, New Zealand.
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© 2016 IEEE. Texture feature is an important feature descriptor for many image analysis applications. The objectives of this research are to determine distinctive texture features for crowd density estimation and counting. In this paper, we have comprehensively reviewed different texture features and their different possible combinations to evaluate their performance on pedestrian crowds. A two-stage classification and regression based framework have been proposed for performance evaluation of all the texture features for crowd density estimation and counting. According to the framework, input images are divided into blocks and blocks into cells of different sizes, having varying crowd density levels. Due to perspective distortion, people appearing close to the camera contribute more to the feature vector than people far away. Therefore, features extracted are normalized using a perspective normalization map of the scene. At the first stage, image blocks are classified using multi-class SVM into different density level. At the second stage Gaussian Process Regression is used to re gress low-level features to count. Various texture features and their possible combinations are evaluated on publicly available dataset.

Silvrano Adonias Dantas Neto, Buddhima Indraratna & David Americo Oliveira 1970, 'Prediction of the Shear Behaviour of Clean Joints in Soft Rocks using Perceptron', VII Simpósio Brasileiro de Mecânica das Rochas, VII Simpósio Brasileiro de Mecânica das Rochas, Associação Brasileira de Mecânica dos Solos e Engenharia Geotécnica - ABMS.
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One of the factors that most affects the safety of structures in or on rock masses is the shear behaviour of rock discontinuities. Some analytical models predicting the shear behavior of rock joints have been developed on the basis of experimental data obtained from direct shear tests performed under different boundary stiffness conditions. However, the use of these analytical models sometimes become difficult due to lack of laboratory test results, or even the difficulty of obtaining some of their parameters. The objective of this paper is to present a model that can be used to predict the shear behaviour of soft clean joints using the artificial neural network (ANN) known as perceptron. Results from direct shear tests conducted on idealized saw-tooth synthetic rock joints under different boundary conditions were considered in the development of the proposed ANN model. The following parameters were considered as input for the ANN model training: boundary normal stiffness, asperity height, initial asperity angle, initial normal stress and the horizontal displacement The output of the ANN model is the shear stress at a particular horizontal displacement. The developed ANN model has an A:5-15-5-1 architecture, where each number represents the number of neurons per layer. The coefficients of correlation between the actual test results and the model output values used to evaluate the behaviour of the neural model during training and validation were 0.999 and 0.997, respectively. The shear strength obtained by applying this kind of model can be considered more advantageous for use in practice than that obtained from the analytical models. One of the advantages of this tool is that, once the synaptic weights and bias of the model are known, the prediction of the shear behaviour of the clean joints of soft rocks can be made using a simple spreadsheet with only parameters which represent the initial roughness of the joint and the boundary conditions (CNL or CNS), rather ...

Stone, B, Halkon, B & Harland, A 1970, 'Headform Mounting Performance in Cricket Standard Testing', Procedia Engineering, 11th Conference of the International Sports Engineering Association (ISEA), Elsevier BV, Delft, NETHERLANDS, pp. 401-406.
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© 2016 The Authors. Published by Elsevier Ltd. The current British Standard for head protectors for cricketers specifies a projectile test to ensure that a helmet can prevent the ball penetrating the peak-grille gap and deformation of the grille onto the face. For practical reasons, it is specified that the headform is mounted onto a grounded frame. This study aims to determine whether this 'Fixed' mounting technique influences the response of the headform relative to a theoretically preferable 'Free' suspension. A pressurised air cannon was used to project a 'BOLA'TM ball at three nominal speeds (22, 25 and 28 m/s) and at three target impact locations (136 (Top), 108 (Middle) and 80 (Bottom) mm from the base). High speed video was used to identify the contact duration and accelerometer data were used to assess the peak resultant headform acceleration and velocity during this period. Generally, good agreement between the two scenarios was found in regard to peak resultant headform acceleration, particularly at the 25 and 28 m/s impact speeds. In terms of headform velocity, the two scenarios showed greater variation when the full contact duration was considered, with root mean square deviations ranging from 1.77-5.6 in all testing conditions. However, some portions of the impact were considerably more consistent than others. These initial results indicate that the result of the penetration test, as specified in BS 7928:2013, would be independent of the suspension technique particularly given the convergence of results at the specified standard velocity (28 m/s). Future work should look to identify the loading and unloading phases of an impact, and use this to compare headform response. Thus allowing a more in-depth investigation of headform mounting performance and provide more clarity on the use of the Fixed technique in cricket standard tests.

Stone, BW, Halkon, BJ & Harland, AR 1970, 'An explorative study into the mechanics of projectile impacts to the head', 2016 IRCOBI Conference Proceedings - International Research Council on the Biomechanics of Injury, pp. 369-380.
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There has been little research focused on the mechanics of high-velocity, low-mass projectile impacts to the head. The little work that has been conducted has focused solely on linear acceleration, despite the evidence linking rotational acceleration to the development of brain injury. The aim of this study was to explore the presence of rotational acceleration in projectile impacts and investigate the influence of impact location. A pressurised air cannon was used to project a BOLATM ball at 22 and 28 m.s-1 towards a BSEN 960:2006 headform positioned to elicit impacts at frontal and lateral locations. High-speed video and accelerometer measurements were used to investigate differences in contact duration, ball deformation and average linear and rotational acceleration during loading. Contact duration was found to be independent of impact location or speed. Greater ball deformation was observed in frontal impacts, despite no differences in time to maximum deformation. Average linear acceleration was observed to be greater during the loading phase in the frontal impacts then in the lateral impacts, potentially due to differences in surface geometry, resulting in differences in ball deformation. Average rotational acceleration was greater in lateral impacts potentially due to differences in the moments of inertia of the headform. Rotational acceleration was found to be higher than previously published injury thresholds for concussion and therefore a potentially important factor in projectile impacts, warranting further research.

Sun, QD, Indraratna, B & Nimbalkar, S 1970, 'The Deformation and Degradation of Granular Material under High-Frequency Cyclic Loading', Geotechnical and Structural Engineering Congress 2016, Geotechnical and Structural Engineering Congress 2016, American Society of Civil Engineers, Pheonix, Arizona, United States, pp. 1700-1707.
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© ASCE.In order to understand the permanent deformation and degradation of railway ballast under high speed train loading, a series of cyclic triaxial tests were conducted using large-scale cylindrical apparatus. The frequency was used from 5 Hz to 60 Hz corresponding to the train speeds from about 40 km/h to 400 km/h. Three types of permanent deformation mechanisms were observed in response to the applied cyclic loads, namely, plastic shakedown at relatively lower frequency, ratcheting at an increased frequency, and plastic collapse at higher frequencies. Correspondingly, four types of particle degradation were observed. The magnitudes of ballast deformation and degradation were found to increase with the frequency and number of load cycles. A critical train speed was identified. Moreover, a good correlation was obtained between particle breakage and volumetric strain under cyclic loading.

Sun, W-J, Chen, C, Liu, S-Q, Sun, D-A, Liang, X-H, Tan, Y-Z & Fatahi, B 1970, 'Study on GMZ bentonite-sand mixture by undrained triaxial tests', E3S Web of Conferences, European Conference on Unsaturated Soils, EDP Sciences, Paris, France, pp. 18006-18006.
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© 2016 The Authors.It is particularly necessary to study the deformation, strength and the changes of pore water pressure of bentonite-based buffer/backfill materials under the undrained condition. A series of isotropic compression tests and triaxial shear tests under undrained conditions were conducted on the compacted saturated/unsaturated GMZ bentonite-sand mixtures with dry mass ratio of bentonite/sand of 30:70. During the tests, the images of the sample were collected by photographic equipment and subsequently were cropped, binarized and centroids marked by image processing technique. Based on identification of the variation of the position of marked centroids, the deformation of the sample can be determined automatically in real-time. Finally, the hydro-mechanical behaviour of saturated and unsaturated bentonite-sand mixtures under the undrained condition can be obtained. From results of triaxial shear tests on unsaturated samples under constant water content, inflated volumetric deformation transforms to contractive volumetric deformation due to the increase of the confining pressure and lateral expansion deformation are observed due to the increase in the shearing stress. Moreover, the net mean stress affects the initial stiffness, undrained shear strength and deformation of the sample during the undrained shear tests.

Suwanwiwat, H, Pal, U & Blumenstein, M 1970, 'An Automatic Off-Line Short Answer Assessment System Using Novel Hybrid Features', 2016 International Conference on Digital Image Computing: Techniques and Applications (DICTA), 2016 International Conference on Digital Image Computing: Techniques and Applications (DICTA), IEEE, Gold Coast, Queensland, Australia.
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To date, paper-based examinations are still in use worldwide on all levels of education levels (e.g. secondary, tertiary levels). However, literature regarding off-line automatic assessment systems employing off-line handwriting recognition is not numerous. This paper proposes an off-line automatic assessment system employing a hybrid feature extraction technique - a newly proposed Modified Direction and Gaussian Grid Feature (MDGGF), along with its enhanced technique. In this study other original feature extraction techniques, together with their enhanced features, were also used for feature extraction technique efficiency comparison purposes. Classifiers, namely artificial neural networks and support vector machines, were selected to be employed in the experiments. Two types of datasets were employed in the experiment for both feature extraction technique accuracy and efficiency comparisons. The best correctly recognised rate of 98.33% with 100% accuracy was obtained when employing the proposed MDGGF to the off-line automatic assessment system.

Suwanwiwat, H, Pal, U & Blumenstein, M 1970, 'An investigation of novel combined features for a handwritten short answer assessment system', Proceedings of International Conference on Frontiers in Handwriting Recognition, ICFHR, International Conference on Frontiers in Handwriting Recognition, IEEE, pp. 102-107.
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This paper proposes an off-line automatic assessment system utilising novel combined feature extraction techniques. The proposed feature extraction techniques are 1) the proposed Water Reservoir, Loop, Modified Direction and Gaussian Grid Feature (WRL-MDGGF), 2) the proposed Gravity, Water Reservoir, Loop, Modified Direction and Gaussian Grid Feature (G-WRL-MDGGF). The proposed feature extraction techniques together with their original features and other combined feature extraction techniques were employed in an investigation of the efficiency of feature extraction techniques on an automatic off-line short answer assessment system. The proposed system utilised two classifiers namely, artificial neural networks and Support Vector Machines (SVMs), two type of datasets and two different thresholds in this investigation. Promising recognition rates of 94.85% and 94.88% were obtained when the proposed WRL-MDGGF and G-WRL-MDGGF were employed, respectively, using SVMs.

Teng, J, Zhang, S, He, Z & Sheng, D 1970, 'A New Mechanism of Canopy Effect in Unsaturated Freezing Soils', E3S Web of Conferences, 3rd European Conference on Unsaturated Soils (E-UNSAT), EDP Sciences, Paris, FRANCE, pp. 16008-16008.
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Wang, B, Gao, Y, Sun, C, Blumenstein, M & La Salle, J 1970, 'A Local Scale Selection Scheme for Multiscale Area Integral Invariants', 2016 International Conference on Digital Image Computing: Techniques and Applications (DICTA), 2016 International Conference on Digital Image Computing: Techniques and Applications (DICTA), IEEE, Gold Coast, QLD, Australia.
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© 2016 IEEE.Area integral invariant (AII) is a functional obtained by performing integral operations on the closed planar contour of a shape via the convolution with disc kernels. This shape descriptor is insensitive to noise and robust with respect to occlusions. AII intrinsically introduces the notion of scale using the size of kernel radius. However how to select an optimal scale remains unresolved. In this paper, we propose a local scale selection scheme for generating multiscale area integral invariants. For the same scale level, the disc kernel size is not fixed and varies with the contour point where the disc is centered. This scheme also provides a scale assignment for emphasising the features extraction at finer scales. The strong discriminative power of the multiscale area integral invariant derived from the proposed scale selection scheme has been validated through experiments on very challenging leaf image retrievals.

Wang, Q, Ye, X, Wang, S, Sloan, SW & Sheng, D 1970, 'Degree of saturation effect on the grout-soil interface shear strength of soil nailing', E3S Web of Conferences, 3rd European Conference on Unsaturated Soils (E-UNSAT), EDP Sciences, Paris, FRANCE, pp. 15007-15007.
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Wang, S, Wang, Q, Ye, X, Sloan, SW & Sheng, D 1970, 'Experimental Study on an Ideal Compaction Grouting into Sand', Geo-China 2016, Fourth Geo-China International Conference, American Society of Civil Engineers, Shandong, PEOPLES R CHINA, pp. 77-84.
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Wang, Y, Sheng, D, Ross, K & Toll, DG 1970, 'Modelling of the water retention characteristic of deformable soils', E3S Web of Conferences, 3rd European Conference on Unsaturated Soils (E-UNSAT), EDP Sciences, Paris, FRANCE, pp. 11005-11005.
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Xu, B, Zhou, Y, Jiang, Y, He, B, Shen, X & Guan, Y 1970, 'Experimental study of distributed optical fiber sensor in measuring the deformation of large filling bag with dredged soil', 2016 10th International Conference on Sensing Technology (ICST), 2016 10th International Conference on Sensing Technology (ICST), IEEE.
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Xu, R, Fatahi, B & Hokmabadi, AS 1970, 'Influence of Soft Soil Shear Strength on the Seismic Response of Concrete Buildings Considering Soil-Structure Interaction', Geo-China 2016, Fourth Geo-China International Conference, American Society of Civil Engineers, Jinan, Shandong, China, pp. 17-24.
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© ASCE. Influences of undrained shear strength on seismic response of moment resisting concrete building considering soil-structure interaction (SSI) have been studied. A 15-storey building model resting on class Ee soil with different values of undrained shear strength has been simulated through FLAC3D. Fully nonlinear dynamic analysis under four different earthquakes including two far-field and two near-field recordings has been conducted by direct method and results in terms of base shear, maximum lateral displacement, inter-storey drift and spectral acceleration have been compared and discussed. Results indicate that by increasing the undrained shear strength of the subsoil, the superstructure experiences extra base shear under earthquake excitations due to SSI. Furthermore, the maximum lateral displacements and inter-storey drifts of the superstructure increase by adopting higher values for the undraied shear strength of the subsoil. It is concluded that practicing engineers should treat soil properties gained from field or laboratory tests with extreme care when dealing with numerical based seismic design of the soil-structure systems.

Yi, W, Li, B, Fan, X, Yang, W & Chen, F 1970, 'Bayesian optimization of partition layouts for mondrian processes', IJCAI International Joint Conference on Artificial Intelligence, pp. 2160-2166.
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The Mondrian process (MP) produces hierarchical partitions on a product space as a kd-tree, which can be served as a flexible yet parsimonious partition prior for relational modeling. Due to the recursive generation of partitions and varying dimensionality of the partition state space, the inference procedure for the MP relational modeling is extremely difficult. The prevalent inference method reversible-jump MCMC for this problem requires a number of unnecessary retrospective steps to transit from one partition state to a very similar one and it is prone to fall into a local optimum. In this paper, we attempt to circumvent these drawbacks by proposing an alternative method for inferring the MP partition structure. Based on the observation that similar cutting rate measures on the partition space lead to similar partition layouts, we propose to impose a nonhomogeneous cutting rate measure on the partition space to control the layouts of the generated partitions - the original MCMC sampling problem is thus transformed into a Bayesian global optimization problem. The empirical tests demonstrate that Bayesian optimization is able to find better partition structures than MCMC sampling with the same number of partition structure proposals.

Zhang, Z, Oberst, S & Lai, JCS 1970, 'Influence of contact condition and sliding speed on friction-induced instability', ICSV 2016 - 23rd International Congress on Sound and Vibration: From Ancient to Modern Acoustics, International Congress on Sound and Vibration: From Ancient to Modern Acoustics (ICSV), International Institute of Acoustics and Vibration, Athens, Greece.
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Brake squeal, defined as audible noise above 1 kHz, is triggered by energy provided in the contact area between the pad and the disc and friction-induced instabilities. Owing to customers' demand of reducing vehicle noise and the increasing use of light composite materials in cars, squealing brakes remain a major concern to the automotive industry because of warranty-related claims. The prediction of disc brake squeal propensity is as challenging as ever. Although friction-induced instabilities are inherently nonlinear and during squeal the brake system's operating and environmental conditions keep changing, mostly linear and steady state methods are used for the analysis of brake squeal propensity. While many different instability mechanisms have been identified, their interactions and the resulting dynamics are not yet fully understood. Linear instability predictions suffer from over- and under-predictions and have to be complemented by extensive noise dynamometer or in vehicle tests. Recent studies indicate that frictional contact is multi-scaled in nature, highly sensitive and inhomogeneous. Very high local pressures and partial contact separations in the contact interface further complicate its numerical modelling. By studying an analytical model of 3 × 3 friction oscillators using three different friction laws (Amonton-Coulomb, the velocity-dependent and the LuGre friction model) in point contact with a sliding rigid plate and incorporating uncertainties in the contact condition, robustly unstable vibration modes have been identified in our previous research. Here, the number and the combination of friction oscillators engaged in contact are randomised to model imperfect contact. In addition, the effect of the variation in the plate's sliding velocity on the in-stability analysis is investigated with randomised friction coefficient of the Amonton-Coulomb friction model. Results of instability prediction and net work calculations are used to illust...

Zhou, A & Sheng, D 1970, 'Relating shear strength of unsaturated soils with capillary water retention curve', E3S Web of Conferences, 3rd European Conference on Unsaturated Soils (E-UNSAT), EDP Sciences, Paris, FRANCE, pp. 14010-14010.
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Zhou, J, Khawaja, MA, Li, Z, Sun, J, Wang, Y & Chen, F 1970, 'Making machine learning useable by revealing internal states update - a transparent approach', International Journal of Computational Science and Engineering, Inderscience Publishers, pp. 378-378.
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Machine learning (ML) techniques are often found difficult to apply effectively in practice because of their complexities. Therefore, making ML useable is emerging as one of active research fields recently. Furthermore, an ML algorithm is still a 'black-box'. This 'black-box' approach makes it difficult for users to understand complicated ML models. As a result, the user is uncertain about the usefulness of ML results and this affects the effectiveness of ML methods. This paper focuses on making a 'black-box' ML process transparent by presenting real-time internal status update of the ML process to users explicitly. A user study was performed to investigate the impact of revealing internal status update to users on the easiness of understanding data analysis process, meaningfulness of real-time status update, and convincingness of ML results. The study showed that revealing of the internal states of ML process can help improve easiness of understanding the data analysis process, make real-time status update more meaningful, and make ML results more convincing.

Fatahi, B 2016, 'Geo-China 2016', American Society of Civil Engineers, USA, pp. 1-240.
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