Abdul-Hadi, A, Mansor, S, Pradhan, B & Tan, CK 2013, 'Seasonal variability of chlorophyll-a and oceanographic conditions in Sabah waters in relation to Asian monsoon—a remote sensing study', Environmental Monitoring and Assessment, vol. 185, no. 5, pp. 3977-3991.
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Abdullahi, S & Pradhan, B 2013, 'Applied Spatial Analysis and Policy'.
AKCAPINAR SEZER, E, PRADHAN, B & GOKCEOGLU, C 2013, 'Erratum to: Manifestation of an adaptive neuro-fuzzy model on landslide susceptibility mapping: Klang valley, Malaysia [Expert Systems with Applications', Expert systems with applications, vol. 40, no. 6.
Al Rawashdeh, S, Ruzouq, R, Al-Fugara, A, Pradhan, B, Ziad, SHA-H & Ghayda, AR 2013, 'Monitoring of Dead Sea water surface variation using multi-temporal satellite data and GIS', Arabian Journal of Geosciences, vol. 6, no. 9, pp. 3241-3248.
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AlAamri, H, Abolhasan, M, Franklin, D & Lipman, J 2013, 'Optimised relay selection for route discovery in reactive routing', AD HOC NETWORKS, vol. 11, no. 1, pp. 70-88.
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On-demand routing protocols have the potential to provide scalable information delivery in large ad hoc networks. The novelty of these protocols is in their approach to route discovery, where a route is determined only when it is required by initiating a route discovery procedure. Much of the research in this area has focused on reducing the route discovery overhead when prior knowledge of the destination is available at the source or by routing through stable links. Hence, many of the protocols proposed to date still resort to flooding the network when prior knowledge about the destination is un-available. This paper proposes a novel routing protocol for ad hoc networks, called On-demand Tree-based Routing Protocol (OTRP). This protocol combines the idea of hop-by-hop routing (as used by AODV) with an efficient route discovery algorithm called Tree-based Optimised Flooding (TOF) to improve scalability of ad hoc networks when there is no prior knowledge about the destination. To achieve this in OTRP, route discovery overheads are minimised by selectively flooding the network through a limited set of nodes, referred to as branching nodes. The key factors governing the performance of OTRP are theoretically analysed and evaluated, including the number of branch nodes, location of branching nodes and number of Route REQuest (RREQ) retries. It was found that the performance of OTRP (evaluated using a variety of well-known metrics) improves as the number of branching nodes increases and the number of consumed RREQ retries is reduced. Additionally, theoretical analysis and simulation results shows that OTRP outperforms AODV, DYMO, and OLSR with reduced overheads as the number of nodes and traffic load increases. © 2012 Elsevier B.V. All rights reserved.
Al-Kouri, O, Al-Fugara, A, Al-Rawashdeh, S, Sadoun, B, Sadoun, B & Pradhan, B 2013, 'Geospatial Modeling for Sinkholes Hazard Map Based on GIS & RS Data', Journal of Geographic Information System, vol. 05, no. 06, pp. 584-592.
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Al-Kouri, O, Al-Rawashdeh, S, Sadoun, B, Sadoun, B & Pradhan, B 2013, 'Geospatial modeling for sinkholes hazard map based on GIS & RS data', Journal of Geographic Information System, vol. 5, no. 06, p. 584.
Al-shalabi, M, Billa, L, Pradhan, B, Mansor, S & Al-Sharif, AAA 2013, 'Modelling urban growth evolution and land-use changes using GIS based cellular automata and SLEUTH models: the case of Sana’a metropolitan city, Yemen', Environmental Earth Sciences, vol. 70, no. 1, pp. 425-437.
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Al-shalabi, M, Pradhan, B, Billa, L, Mansor, S & Althuwaynee, OF 2013, 'Manifestation of Remote Sensing Data in Modeling Urban Sprawl Using the SLEUTH Model and Brute Force Calibration: A Case Study of Sana’a City, Yemen', Journal of the Indian Society of Remote Sensing, vol. 41, no. 2, pp. 405-416.
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Al-sharif, AAA, Pradhan, B, Shafri, HZM & Mansor, S 2013, 'Spatio-temporal analysis of urban and population growths in tripoli using remotely sensed data and GIS', Indian Journal of Science and Technology, vol. 6, no. 8, pp. 5134-5142.
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The remote sensing data and GIS have been used widely to analyse and study the patterns of urban expansions. The capital of Libya, Tripoli was selected to perform this study and to examine its urban growth. Four satellite imageries and population censuses of the study area for the time period 1984 to 2010 were used in this work. The objectives of this paper are identifying and analysing the urban sprawl of Tripoli as a pattern and as process. Also to understand and assess the interchangeable relationship of urban growth and population growth of study area. Urban area extents in different time periods were extracted by supervised classification method of the satellite imageries. Then, the population data and urban extents data were coupled to perform the analysis. Additionally, Shannon's entropy technique was used for further assessment of urban growth. The study findings demonstrate that Tripoli had sprawled urban growth during the period 1984 to 2010. Moreover, during the above mentioned period, the urban expansion dispersion rate has shown in an ascending mode. Consequently, this uncontrolled dispersed urban development had resulted in high consumption land rate per capita despite of decrement in population growth rate.
Banasiak, L, Indraratna, B, Regmi, G, Golab, A & Lugg, G 2013, 'Characterisation and assessment of recycled concrete aggregates used in a permeable reactive barrier for the treatment of acidic groundwater', Geomechanics and Geoengineering, vol. 8, no. 3, pp. 155-166.
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The acidification of coastal waterways because of acid sulphate soil is an environmental, economic and social problem within Australia. A pilot-scale permeable reactive barrier (PRB), using recycled concrete aggregates as reactive material, was installed in low-lying acid sulphate soil terrain for acidic groundwater remediation. Column experiments were previously undertaken with synthetic groundwater to ascertain the dominant reactions occurring within the PRB. Results showed that armouring of the reactive material surface by precipitated Al- and Fe-bearing minerals significantly reduced its acid neutralisation capacity (ANC). The purpose of this current study was to validate this decline in ANC through characterisation of the virgin and armoured concrete aggregates, and precipitates that formed on the concrete. Samples of concrete aggregates and precipitates were analysed using X-ray diffraction (XRD), X-ray fluorescence (XRF), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy-Energy dispersive spectroscopy (SEM-EDS) and X-ray micro-computed tomography (μCT). The conclusions drawn from these analyses are that Al-bearing (gibbsite 14.3%, boehmite 10.9%) and Fe-bearing (goethite 38.2%) mineral precipitates of diverse morphology form as a thin layer coating the aggregate surfaces. A reduction of CaO in the armoured concrete aggregates by 47% correlates with the reduction in ANC of the virgin concrete by 50% due to armouring. © 2013 Copyright Taylor and Francis Group, LLC.
Billa, L & Pradhan, B 2013, 'GIS modeling for selection of a transfer station site for residential solid waste separation and recycling', Pertanika Journal of Science and Technology, vol. 21, no. 2, pp. 487-498.
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In this study a GIS model was developed and spatial analytical techniques performed to identify and select a suitable location for a waste transfer station in the sprawling suburban town of Petaling Jaya. The lack of a transfer station in urban centres of Malaysia has caused many problems and affects the efficiency of waste collection and disposal. With diminishing space for landfills and the increasing cost of solid waste management, the need for urban solid-waste recycling has become very important. However, finding a place for waste to be efficiently sorted before unwanted waste can be carried to disposal landfills has social and physical constraints. This study applies GIS techniques and analysis for site selection and identifies an acceptable area. In the model, environmental, physical and social constraints were taken into account, resulting in the selection of a potential area that is acceptable to the residents of the area because it is out of range of causing public nuisance and within minimum travelling distance for collection vehicles. The results show that the potential location for the transfer station should be in proximity of the industrial area of Petaling Jaya, allowing for the possible sale of recyclable materials to local industries. The location is also sited near a major highway to allow quick transportation of the rest of the unwanted waste to the landfill. © 2013 Universiti Putra Malaysia Press.
Biro, K, Pradhan, B, Buchroithner, M & Makeschin, F 2013, 'LAND USE/LAND COVER CHANGE ANALYSIS AND ITS IMPACT ON SOIL PROPERTIES IN THE NORTHERN PART OF GADARIF REGION, SUDAN', Land Degradation & Development, vol. 24, no. 1, pp. 90-102.
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ABSTRACTSeveral decades of intensive dry land farming in the Gadarif region, located in the Eastern part of Sudan, has led to rapid land use/land cover (LULC) changes mainly due to agricultural expansion, government policies and environmental calamities such as drought. In this paper, an attempt has been made to analyse and monitor the LULC changes using multi‐temporal Landsat data for the years 1979, 1989 and 1999 and ASTER data for the year 2009. In addition, efforts were made to discuss the impact of LULC changes on the selected soil properties. For this, a post‐classification comparison technique was used to detect LULC changes from satellite images. Primarily, three main LULC types were selected to investigate the properties of soil, namely, cultivated land, fallow land and woodland. Moreover, soil samples were also collected at two depths of surface soil from ten sample plots for each of the LULC type. For these soil samples, various soil properties such as texture, bulk density, organic matter, soil pH, electrical conductivity, sodium adsorption ratio, phosphorous and potassium were analysed. The results showed that a significant and extensive change of LULC patterns has occurred in the last three decades in the study area. Further, laboratory tests revealed that soil properties were significantly affected by these LULC changes. The change of the physical and chemical properties of the soil may have attributed to the changes in the LULC resulting in land degradation, which in turn has led to a decline in soil productivity. Copyright © 2011 John Wiley & Sons, Ltd.
Biro, K, Pradhan, B, Sulieman, H & Buchroithner, M 2013, 'Exploitation of TerraSAR-X Data for Land use/Land Cover Analysis Using Object-Oriented Classification Approach in the African Sahel Area, Sudan', Journal of the Indian Society of Remote Sensing, vol. 41, no. 3, pp. 539-553.
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Biro, K, Pradhan, B, Sulieman, H & Buchroithner, M 2013, 'Exploitation of TerraSAR-X data for land use/land cover analysis using object-oriented classification approach in the African Sahel Area, Sudan', Journal of the Indian Society of Remote Sensing, vol. 41, no. 3, pp. 539-553.
Bu, GP, Son, JB, Lee, JH, Guan, H, Blumenstein, M & Loo, YC 2013, 'Typical deterministic and stochastic bridge deterioration modelling incorporating backward prediction model', Journal of Civil Structural Health Monitoring, vol. 3, no. 2, pp. 141-152.
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© Springer-Verlag Berlin Heidelberg 2013. A backward prediction model (BPM) has been developed to generate the missing bridge condition ratings in past years, thereby ensuring adequate condition data as required in long-term performance modelling. The BPM establishes a correlation between the known condition ratings and the non-bridge factors, including climate condition, traffic volume and population growth. The aim of this study is to confirm the ability of BPM in improving the prediction accuracy using the existing bridge deterioration models. The prediction accuracies of typical deterministic and stochastic bridge deterioration models are compared when different sets of BPM-generated historical condition ratings are used as input. Comparisons indicate that the prediction error decreases as more historical condition ratings are made available. Notwithstanding the above findings, several limitations of the current deterministic and stochastic bridge deterioration models are also worth noting and further research is essential to improve the prediction accuracy of bridge deterioration modelling.
Cai, C, Wang, Y & Geers, G 2013, 'Vehicle‐to‐infrastructure communication‐based adaptive traffic signal control', IET Intelligent Transport Systems, vol. 7, no. 3, pp. 351-360.
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Callow, D, Lee, J, Blumenstein, M, Guan, H & Loo, Y-C 2013, 'Development of hybrid optimisation method for Artificial Intelligence based bridge deterioration model — Feasibility study', Automation in Construction, vol. 31, pp. 83-91.
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Chai, J, Sheng, D, Carter, JP & Zhu, H 2013, 'Corrigendum to “Coefficient of consolidation from non-standard piezocone dissipation curves” [Comput. Geotech. 41 (2012) 13–22]', Computers and Geotechnics, vol. 51, pp. 128-128.
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Che Mat, R, Shariff, ARM, Pradhan, B, Mahmud, AR, Shafry, M, Rahim, M & Rehman, A 2013, 'A Comparison between four-tier framework and three-tier framework for online applications of 3D GIS visualization', Life Science Journal, vol. 10, no. 3, pp. 1534-1540.
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Online application of 3D visualization for GIS (Geographic Information System) data is of interest to not only professionals such as cartographers, geographers, geologists and psychologists but also popular among the ordinary people. The system's conventional design is generated from client/server based architecture. This architecture is the main platform for designing the online system architecture, which works based on the distributing concept which is 'tier'. The tier is required to separate the works/tasks between the system architecture. Currently, three-tiers architecture is the most well-known architecture used in GIS applications and other application. However, this architecture has a drawback on the middle tier which needs more processing power to meet the request from multiple of users. GIS applications, especially which involve 3D visualization generate a massive amount of data. Due to this situation, the use of the current three-tier framework for online application of 3D visualization for GIS will decrease the performance of the system in terms of time for processing the request from the users. The aim of this study is to introduce the new four-tier framework and compare it with the existing three-tier framework. This framework consist of four-tier architecture, which is divided into client tier, logic tier, visualization process tier, and database tier. The comparison is based on response time, loading time, frames rate per second, CPU usage, and memory usage. The new framework shows superiority in its performance, and the processing power is reduced.
Cheng, S, Ji, JC & Zhou, J 2013, 'Fast synchronization of directionally coupled chaotic systems', APPLIED MATHEMATICAL MODELLING, vol. 37, no. 1-2, pp. 127-136.
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The fast synchronization of directionally coupled chaotic systems under a chained interaction topology is studied by applying finite-time stability theory. It is shown that all chaotic systems can achieve synchronization in finite time as long as the coupling strength is strong enough. It is proved that the settling times are determined by the interaction strength, system parameters and initial conditions of the chaotic systems. Furthermore, it is found that the settling times are mainly dependent on the bounded value and dimension of the coupled chaotic systems when the individual chaotic sub-system is bounded. Finally, illustrative examples and numerical simulations are given to show the correctness of theoretical results.
Dackermann, U, Li, J & Samali, B 2013, 'Identification of member connectivity and mass changes on a two-storey framed structure using frequency response functions and artificial neural networks', JOURNAL OF SOUND AND VIBRATION, vol. 332, no. 16, pp. 3636-3653.
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This paper presents a structural health monitoring (SHM) technique that utilises pattern changes in frequency response functions (FRFs) as input parameters for a system of artificial neural networks (ANNs) to assess the structural condition of a structure. To verify the proposed method, it is applied to numerical and experimental models of a two-storey framed structure, on which structural damage is induced by member connectivity and mass changes, respectively. For the numerical structure, simulated time-history data are polluted with various levels of white Gaussian noise in order to realistically represent field-testing conditions. As a damage indicator, residual FRFs are used, which are derived by calculating the differences in FRF data between the undamaged/baseline structure and the structure with changed joint conditions or added mass. To obtain suitable patterns for neural network training, principal component analysis (PCA) techniques are adopted to reduce the size of the residual FRF data and to filter noise. A hierarchical system of individual ANNs, termed network ensemble, is then trained to map changes in PCA-reduced residual FRFs to damage conditions. The results obtained for both damage investigations, namely joint damage and mass changes, demonstrate that the proposed SHM technique is accurate and reliable in assessing the condition of the test structure numerically and experimentally based on direct FRF measurements and network ensemble analysis. From the outcomes of the individual networks, it is found that the proposed hierarchical network ensemble approach is highly efficient in filtering poor results of underperforming networks obtained from measurement locations with low damage sensitivity. © 2013 Elsevier Ltd.
Dackermann, U, Li, J, Rijal, R & Samali, B 2013, 'A Vibration-Based Approach for the Estimation of the Loss of Composite Action in Timber Composite Systems', STRUCTURAL HEALTH ASSESSMENT OF TIMBER STRUCTURES, vol. 778, pp. 462-469.
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This paper presents a novel approach for the determination of the loss of composite action for timber composite systems using only measurements from non-destructive vibration testing. Traditionally, the composite action of a system is evaluated from static load testing using deflection measurements. However, static load testing is expensive, time consuming and inappropriate for existing flooring systems. The method proposed in this paper is based on the Damage Index (DI) method, which uses changes in modal strain energies, to detect locations and severities of damage. In the proposed method, a new Loss of Composite Action Index (LCAI), which is derived from direct mode shape measurements obtained from dynamic testing, is introduced to evaluate the loss of composite action. The proposed method is tested and validated on numerical and experimental models of a timber composite beam structure, which consists of two timber components that are connected with different numbers of screws to simulate various degrees of partial composite states. The results obtained from the new method are very encouraging and show a clear trend of the proposed dynamic-based LCAI in indicating the loss of composite action in the investigated timber composite structure. © (2013) Trans Tech Publicutions, Switzerland.
Daqamseh, ST, Mansor, S, Pradhan, B, Billa, L & Mahmud, AR 2013, 'Potential fish habitat mapping using MODIS-derived sea surface salinity, temperature and chlorophyll-a data: South China Sea Coastal areas, Malaysia', Geocarto International, vol. 28, no. 6, pp. 546-560.
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Devkota, KC, Regmi, AD, Pourghasemi, HR, Yoshida, K, Pradhan, B, Ryu, IC, Dhital, MR & Althuwaynee, OF 2013, 'Landslide susceptibility mapping using certainty factor, index of entropy and logistic regression models in GIS and their comparison at Mugling–Narayanghat road section in Nepal Himalaya', Natural Hazards, vol. 65, no. 1, pp. 135-165.
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Diyaljee, V 2013, 'Discussion of “Stress-Strain Degradation Response of Railway Ballast Stabilized with Geosynthetics” by Buddhima Indraratna and Sanjay Nimbalkar', Journal of Geotechnical and Geoenvironmental Engineering, vol. 139, no. 12, pp. 2232-2233.
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Dom, NC, Ahmad, AH, Latif, ZA, Ismail, R & Pradhan, B 2013, 'Coupling of remote sensing data and environmental-related parameters for dengue transmission risk assessment in Subang Jaya, Malaysia', Geocarto International, vol. 28, no. 3, pp. 258-272.
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Elsener, R, Dackermann, U, Li, J, Samali, B & Crews, K 2013, 'Experimental Investigations of Material Properties of Timber Utility Poles using various Material Testing Approaches', STRUCTURAL HEALTH ASSESSMENT OF TIMBER STRUCTURES, vol. 778, pp. 265-272.
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Fatahi, B & Khabbaz, H 2013, 'Optimising the pattern of semi-rigid columns to improve performance of rail tracks overlying soft soil formation', Australian Geomechanics Journal, vol. 48, no. 3, pp. 89-97.
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With Australia facing a rapid increase in population in the next 30 years, the government is being proactive in handling the forecasted growth. The release of 2010 Metropolitan Transport Plan by the New South Wales (NSW) Government shows that the State of NSW will see an increase in commuter travel by rail. The NSW rail system is one of the most complex networks in the world and due to population growth, the network will require further expansion with construction of new railway lines partly on weak and marginal ground and will also require more frequent train running on existing lines. This study seeks to identify the effectiveness of semi-rigid inclusion ground improvement techniques particularly stone columns and deep soil mixing in controlling settlement of soft soils when placed under the dead loads of the rail structure and the large live loads of freight trains. The employed numerical study assesses the relationship between the column position in the track cross section and the overall settlement of the ballasted rail formation. The numerical results show that the overall settlement of the track reduces significantly with the use of columns close to the centre of the track and not just under the rail. In addition, application of one layer of geogrids between sub-ballast and sub-grade assists to reduce the maximum settlement of track decreasing the future maintenance costs.
Fatahi, B & Khabbaz, H 2013, 'PREDICTING SETTLEMENT OF CHEMICALLY STABILISED LANDFILLS', INTERNATIONAL JOURNAL OF GEOMATE, vol. 5, no. 10, pp. 700-705.
Fatahi, B, Fatahi, B, Le, TM & Khabbaz, H 2013, 'Small-strain properties of soft clay treated with fibre and cement', GEOSYNTHETICS INTERNATIONAL, vol. 20, no. 4, pp. 286-300.
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To improve the dynamic properties of soft soil, the cement treatment technique combined with fibre reinforcement can be employed. In this study, the effects of two types of fibres (polypropylene and recycled carpet) on the hardening process and small-strain properties of cement-treated kaolinite and bentonite clays are investigated. Cement-treated clay specimens were prepared using cement contents of 5%, 10% and 15% by weight of dry soil for the kaolinite samples, and 30%, 40% and 50% for the bentonite samples. To investigate and understand the influence of different fibre types and contents, three different percentages of fibre content were adopted: 0.1%, 0.2% and 0.5% polypropylene fibres, and 0.5%, 0.75% and 1% carpet fibres. The results of bender element tests on 126 cylindrical samples of cement-treated clay with various cement and fibre contents were analysed to discern the relationships between fibre and cement content and the small-strain mechanical properties, including the shear wave velocity and maximum small-strain shear modulus of the treated soil. The influence of fibres and cement contents on the hardening time of treated soil has also been investigated. © 2013 Thomas Telford Ltd.
Fatahi, B, Le, TM, Fatahi, B & Khabbaz, H 2013, 'Shrinkage Properties of Soft Clay Treated with Cement and Geofibers', Geotechnical and Geological Engineering, vol. 31, no. 5, pp. 1421-1435.
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In this study, effects of two types of geofibers, namely polypropylene and recycled carpet, on three dimensional shrinkage properties of cement treated kaolinite and bentonite clays are investigated. Cement treated clay specimens were prepared with cement contents of 5, 10, and 15 % by weight of dry soil for kaolinite samples, and 30, 40 and 50 % for bentonite samples. To investigate and understand the influence of different fiber types and contents, three different percentages of fiber content (i.e. 0.1, 0.2 and 0.5 % polypropylene fibers; and 0.5, 0.75 and 1 % carpet fibers) were adopted. The results of shrinkage tests on 126 cylindrical samples of cement treated clay with various cement and fiber contents were analysed to understand the relationships between these parameters and the shrinkage percentage of treated soil. Results of this study indicate that combination of cement and fiber is effective in reducing the volume change of clayey soils undergoing drying process. In the applied ranges of cement and fiber contents, the influence of cement addition on the shrinkage reduction is more significant than the addition of fibers for the treated kaolinite. However, addition of fibers in curtailing the shrinkage of bentonite clay is more significant than the cement addition. © 2013 Springer Science+Business Media Dordrecht.
Fatahi, B, Le, TM, Le, MQ & Khabbaz, H 2013, 'Soil creep effects on ground lateral deformation and pore water pressure under embankments', Geomechanics and Geoengineering, vol. 8, no. 2, pp. 107-124.
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Analysing the behaviour of the soft ground under embankments is a challenging task and is of significant interest to practising geotechnical engineers. This paper revisits a well known case study of an embankment of Boston Blue Clay, which was thoroughly instrumented and measured with piezometers, settlement rods and inclinometers over a long time period during and after construction. The soil parameters were very comprehensively collected by both in situ and laboratory tests in several major test programs. The behaviour of the ground considering the modified Cam-Clay model including and excluding soil creep is simulated using finite element method. The analysed data are verified with field measurements and a parametric study is conducted to evaluate the influence of creep index on excess pore water pressures generated and the displacement of the ground under the embankment. It is observed that both horizontal displacements and excess pore water pressures of the ground under the embankment increased by the creep index. Thus effects of soil creep should be precisely considered in predicting the ground performance under embankments. © 2013 Copyright Taylor and Francis Group, LLC.
Hagelstein, B, Abolhasan, M, Franklin, D & Safaei, F 2013, 'Improving fairness in IEEE 802.11 networks using MAC layer opportunistic retransmission', COMPUTER NETWORKS, vol. 57, no. 17, pp. 3410-3427.
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This paper introduces DAFMAC (Decode And Forward MAC), a scalable opportunistic cooperative retransmission enhancement for the IEEE 802.11 MAC protocol which operates without the need for additional explicit control signalling. Distributed opportunistic retransmission algorithms rely on selecting a single suitable relay without direct arbitration between nodes. Simulations show that DAFMAC offers a significant improvement in fairness for both throughput and jitter, giving multiple parallel data flows a more equal opportunity to utilise the channel. DAFMAC cooperative retransmissions are shown to reduce node energy consumption for a given throughput. Further, the DAFMAC relay selection algorithm is shown to scale very well in terms of complexity and memory requirements in comparison to other cooperative retransmission schemes. © 2013 Elsevier B.V. All rights reserved.
Heitor, A, Indraratna, B & Rujikiatkamjorn, C 2013, 'Laboratory study of small-strain behavior of a compacted silty sand', Canadian Geotechnical Journal, vol. 50, no. 2, pp. 179-188.
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Small-strain behavior is a key indicator for assessing the performance of compacted fills. Compaction conditions, i.e., initial moisture content and applied energy, govern compaction effectiveness and thus, the structure and matric suction of compacted soil. This paper presents an experimental study of the small-strain behavior of compacted silty sand prepared with different compaction conditions. Specimens with varying initial moisture contents and compaction energies were tested with bender elements to determine the small-strain shear modulus (G0), while the post-compaction matric suction was measured using the filter paper method and tensiometer. The experimental data suggest a pronounced relationship between G0and the degree of saturation (Sr) of the as-compacted soil specimens. X-ray computed tomography (CT) scans were performed to examine structural changes of selected specimens upon compaction. The laboratory results are also examined in light of common end-product specifications, which show that it is beneficial to compact the soil slightly dry of optimum moisture content from the modulus point of view.
Herman, G, Zhang, B, Wang, Y, Ye, G & Chen, F 2013, 'Mutual information-based method for selecting informative feature sets', Pattern Recognition, vol. 46, no. 12, pp. 3315-3327.
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Huang, M, Wang, H, Sheng, D & Liu, Y 2013, 'Rotational–translational mechanism for the upper bound stability analysis of slopes with weak interlayer', Computers and Geotechnics, vol. 53, pp. 133-141.
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Indraratna, B & Nimbalkar, S 2013, 'Closure to “Stress-Strain Degradation Response of Railway Ballast Stabilized with Geosynthetics” by Buddhima Indraratna and Sanjay Nimbalkar', Journal of Geotechnical and Geoenvironmental Engineering, vol. 139, no. 12, pp. 2233-2233.
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Indraratna, B & Nimbalkar, S 2013, 'Stress-Strain Degradation Response of Railway Ballast Stabilized with Geosynthetics', Journal of Geotechnical and Geoenvironmental Engineering, vol. 139, no. 5, pp. 684-700.
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Indraratna, B, Athukorala, R & Vinod, J 2013, 'Estimating the Rate of Erosion of a Silty Sand Treated with Lignosulfonate', Journal of Geotechnical and Geoenvironmental Engineering, vol. 139, no. 5, pp. 701-714.
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Indraratna, B, Balasubramaniam, AS, Poulos, H, Rujikiatkamjorn, C & Ameratunga, J 2013, 'Performance and prediction of marine clay treated with vacuum and surcharge consolidation at port of brisbane', Australian Geomechanics Journal, vol. 48, no. 4, pp. 161-180.
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During the past decade, the application of vacuum preloading for stabilising soft coastal clay and other low-lying estuarine soils has become popular in Australia. The cost-effectiveness is a major factor in most projects in view of the significantly reduced time for achieving a relatively high degree of consolidation. Due to an increase in trade activities at the Port of Brisbane, new facilities on Fisherman Islands at the mouth of the Brisbane River will be constructed on the new outer area (235 ha) adjacent to the existing port facilities via land reclamation. A vacuum assisted surcharge load and conventional surcharge scheme in conjunction with prefabricated vertical drains was selected to reduce the required consolidation time through the deeper subsoil layers. The performance of the combined vacuum and surcharge fill system and the construction of the embankment are described in this paper. A comparison of the performance of the vacuum combined surcharge loading system with a standard surcharge fill highlights the clear benefits of vacuum consolidation. Field monitoring data are presented to demonstrate how the embankment performed during construction. The paper also evaluates the relative performance of the two contrasting preloading systems (i.e. vacuum and nonvacuum system). An analytical solution for radial consolidation considering both time-dependent surcharge loading and vacuum pressure is proposed to predict the settlements and associated excess pore pressures of the soft Holocene clay deposits.
Indraratna, B, Basack, S & Rujikiatkamjorn, C 2013, 'Numerical Solution of Stone Column–Improved Soft Soil Considering Arching, Clogging, and Smear Effects', Journal of Geotechnical and Geoenvironmental Engineering, vol. 139, no. 3, pp. 377-394.
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Indraratna, B, Hussaini, SKK & Vinod, JS 2013, 'The lateral displacement response of geogrid-reinforced ballast under cyclic loading', Geotextiles and Geomembranes, vol. 39, pp. 20-29.
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Indraratna, B, Kianfar, K & Rujikiatkamjorn, C 2013, 'Laboratory Evaluation of Coefficient of Radial Consolidation Based on Pore-Water-Pressure Dissipation and Settlement', GEOTECHNICAL TESTING JOURNAL, vol. 36, no. 1, pp. 107-118.
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Indraratna, B, Ngo, NT & Rujikiatkamjorn, C 2013, 'Deformation of Coal Fouled Ballast Stabilized with Geogrid under Cyclic Load', Journal of Geotechnical and Geoenvironmental Engineering, vol. 139, no. 8, pp. 1275-1289.
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This paper presents the results of laboratory investigations into the deformation of coal fouled ballast stabilized with geogrid at various degrees of fouling. A novel track process simulation apparatus was used to simulate realistic rail track conditions subjected to cyclic loading, and the void contamination index (VCI) was used to evaluate the level of ballast fouling. The experimental results show that coal fines act as a lubricant, causing grains of ballast to displace and rotate, and as a result, accelerate its deformation. However, coal fines also reduce ballast breakage because of a cushioning effect, that is, by reducing interparticle attrition. The inclusion of geogrid at the interface between the layer of ballast and subballast provides additional internal confinement and particle interlocking via geogrid apertures, which reduces deformation. A threshold value of VCI540% is proposed to assist practitioners for conducting track maintenance. If the level of fouling exceeds this threshold, the geogrid reinforcement significantly decreases its effectiveness and the fouled ballast exhibits a premature dilation. Based on the experimental results, an equation incorporating the VCI was proposed to predict the deformation of fresh and fouled ballast. This equation improves track design and assists in favorable decision support for track maintenance. Additionally, the discrete element method (DEM) was also used to capture the deformation of fouled ballast subjected to cyclic loading, whereas the DEM results were compared with experimental observations © 2013 American Society of Civil Engineers.
Indraratna, B, Nimbalkar, S & Rujikiatkamjorn, C 2013, 'Modernisation of Rail Tracks for Higher Speeds and Greater Freight', International Journal of Railway Technology, vol. 2, no. 3, pp. 1-20.
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INDRARATNA, B, PREMADASA, W & BROWN, ET 2013, 'Shear behaviour of rock joints with unsaturated infill', Géotechnique, vol. 63, no. 15, pp. 1356-1360.
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Behaviour of soil-infilled rock joints has significant importance with respect to the strength of fractured rock mass. The presence of even a small amount of fine-grained infill material within a joint can reduce its shear strength considerably, depending on the degree of saturation of infill. Therefore, it is crucial to examine how the infill material can adversely affect the joint shear strength. Previous studies of infilled joints have mainly been focused on idealised regular joint patterns owing to the simplicity and reproducibility in laboratory testing. Current literature on infilled rock joints has also neglected the effect of the degree of saturation of infill on the shear behaviour. In most instances, fully saturated infill has been used or assumed, and the contribution of matric suction on the shear strength of joints having unsaturated infill has not been studied. In this study, a series of triaxial tests on natural joint profiles having joint roughness coefficient (JRC) of 10–12 is carried out at constant moisture content. A semi-empirical model is proposed and validated on the basis of laboratory data.
Indraratna, B, Rujikiatkamjorn, C & Balasubramaniam, AS 2013, 'Ground improvement at the port of Brisbane, Australia using vertical drains and vacuum assisted preloading', Geotechnical Special Publication, no. 230, pp. 540-550.
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Soft clays in coastal areas have low shear strength and high compressibility. Thus construction activities for infrastructure developments in these deposits often pose geotechnical problems due to large time dependent settlements and lateral movements. Ground improvement techniques are adopted to reduce the water content of the soft clays by preloading techniques with vertical drains. Depending on the magnitude of the surcharge used substantial immediate settlement with lateral movements can takes place during preloading. This in turn causes stability problems in the loaded areas. The use of vacuum assisted preloading has now become a popular method in Australia where substantial loads need to be carried out to meet a desired rate of settlement and mitigate undrained failure. To assist the vacuum propagation to significant depths, vertical drains are used in conjunction. At the Port of Brisbane, Australia, vacuum assisted surcharge preloading and conventional surcharge preloading schemes were used to reduce the time required for consolidation and long term settlement in soft Holocene clays. The design of the combined vacuum and surcharge fill system and construction of the embankment are described in this paper. A comparison made on the performance of a combined vacuum surcharge loading system with a standard surcharge fill highlights the clear benefits of vacuum consolidation. Field monitoring data on surface and sub-surface settlements, pore pressures and lateral movements on test embankments performed during construction are presented. An analytical solution for radial consolidation that considers both time-dependent surcharge loading and vacuum pressure to predict the settlement and associated excess pore pressures in soft clay deposits is also proposed. © 2013 American Society of Civil Engineers.
INDRARATNA, B, TENNAKOON, N, NIMBALKAR, S & RUJIKIATKAMJORN, C 2013, 'Behaviour of clay-fouled ballast under drained triaxial testing', Géotechnique, vol. 63, no. 5, pp. 410-419.
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Contamination or fouling of rail ballast with external fines, including slurried and pumped subgrade material (e.g. clay and silt), is one of the primary reasons for track deterioration. Fouling causes differential settlement of the track, and also decreases the load-bearing capacity, owing to the reduction in the friction angle of the granular assembly. In certain circumstances, fouled ballast needs to be cleaned or replaced to maintain the desired track stiffness, load-bearing capacity and track alignment, all of which influence safety. This paper presents and discusses the results of a series of large-scale triaxial tests conducted on latite basalt, a rail ballast of volcanic origin, commonly used in Australia. Consolidated drained triaxial tests were conducted under three different levels of confining pressure and varying degrees of clay fouling. Stress–strain degradation characteristics are discussed in detail. This paper also describes the non-linear strength envelope and a novel empirical relationship to capture the detrimental effects of clay fouling on the performance of ballasted tracks.
Kabiri, K, Pradhan, B, Samimi-Namin, K & Moradi, M 2013, 'Detecting coral bleaching, using QuickBird multi-temporal data: A feasibility study at Kish Island, the Persian Gulf', Estuarine, Coastal and Shelf Science, vol. 117, pp. 273-281.
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Kabiri, K, Pradhan, B, Shafri, HZM, Mansor, SB & Samimi-Namin, K 2013, 'A Novel Approach to Estimate Diffuse Attenuation Coefficients for QuickBird Satellite Images: A Case Study at Kish Island, the Persian Gulf', Journal of the Indian Society of Remote Sensing, vol. 41, no. 4, pp. 797-806.
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Kardani, M, Nazem, M, Sheng, D & Carter, JP 2013, 'Large deformation analysis of geomechanics problems by a combined rh-adaptive finite element method', Computers and Geotechnics, vol. 49, pp. 90-99.
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Kianfar, K, Indraratna, B & Rujikiatkamjorn, C 2013, 'Radial consolidation model incorporating the effects of vacuum preloading and non-Darcian flow', GEOTECHNIQUE, vol. 63, no. 12, pp. 1060-1073.
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Kouretzis, GP, Sheng, D & Sloan, SW 2013, 'Sand–pipeline–trench lateral interaction effects for shallow buried pipelines', Computers and Geotechnics, vol. 54, pp. 53-59.
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Krami, LK, Amiri, F, Sefiyanian, A, Shariff, ARBM, Tabatabaie, T & Pradhan, B 2013, 'Spatial patterns of heavy metals in soil under different geological structures and land uses for assessing metal enrichments', Environmental Monitoring and Assessment, vol. 185, no. 12, pp. 9871-9888.
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Lee, J, Blumenstein, M, Guan, H & Loo, Y 2013, 'Minimising uncertainty in long‐term prediction of bridge element', Engineering, Construction and Architectural Management, vol. 20, no. 2, pp. 127-142.
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PurposeSuccessful bridge management system (BMS) development requires a reliable bridge deterioration model, which is the most crucial component in a BMS. Historical condition ratings obtained from biennial bridge inspections are a major source for predicting future bridge deterioration in BMSs. However, historical condition ratings are very limited in most bridge agencies, thus posing a major barrier for predicting reliable future bridge performance. The purpose of this paper is to present a preliminary study as part of a long‐term research on the development of a reliable bridge deterioration model using advanced Artificial Intelligence (AI) techniques.Design/methodology/approachThis proposed study aims to develop a reliable deterioration model. The development work consists of two major Stages: stage 1 – generating unavailable bridge element condition rating records using the Backward Prediction Model (BPM). This helps to provide sufficient historical deterioration patterns for each element; and stage 2 – predicting long‐term condition ratings based on the outcome of Stage 1 using time delay neural networks (TDNNs).FindingsLong‐term prediction using proposed method can also be expressed in the same form of inspection records – element quantities of each bridge element can be predicted. The proposed AI‐based deterioration model does not ignore critical failure risks in small number of bridge elements in low condition states (CSs). This implies that the risk in long‐term predictions can be reduced.Originality/valueThe proposed methodology aims to utilise limited bridge inspection records over a shor...
Li, Y, Li, J & Samali, B 2013, 'On the magnetic field and temperature monitoring of a solenoid coil for a novel magnetorheological elastomer base isolator', 13TH INTERNATIONAL CONFERENCE ON ELECTRORHEOLOGICAL FLUIDS AND MAGNETORHEOLOGICAL SUSPENSIONS (ERMR2012), vol. 412, no. 1, pp. 1-7.
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Following a successful experimental validation of a magnetorheological elastomer (MRE) base isolator, this study presents one of the major concerns, the heating of the magnetic coil, in the design and development of the adaptive MRE based isolator. In this research, the MRE materials, with a total thickness of nearly 150 mm, are placed as the magnetic core of the device to best utilize the magnetic energy provided by the coil. A series of tests are undertaken to investigate the magnetic fields inside the coil with or without the MRE materials. Thermocouples are used to monitoring the surface temperature of the coil when it is applied with various currents for 10 min. It is shown that the measurement of field inside the solenoid when no MRE is placed inside agrees with the theoretical analysis. It is also shown that the temperature of the coil increase dramatically when a current is applied. Cooling of the coil may takes even longer, about 4 h, till down to the room temperature. Dropping of the magnetic field is observed when the temperature goes high. © Published under licence by IOP Publishing Ltd.
Li, Y, Li, J, Li, W & Samali, B 2013, 'Development and characterization of a magnetorheological elastomer based adaptive seismic isolator', SMART MATERIALS AND STRUCTURES, vol. 22, no. 3, pp. 1-12.
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One of the main shortcomings in current base isolation design/practice is lack of adaptability. As a result, a base isolation system that is effective for one type earthquake may become ineffective or may have adverse effect for other earthquakes. The vulnerability of traditional base isolation systems can be exaggerated by two types of earthquakes, i.e. near-field earthquakes and far-field earthquakes. This paper addresses the challenge facing current base isolation design/practice by proposing a new type of seismic isolator for the base isolation system, namely an adaptive seismic isolator. The novel adaptive seismic isolator utilizes magnetorheological elastomer (MRE) for its field-sensitive material property. Traditional seismic isolator design with a unique laminated structure of steel and MRE layers has been adopted in the novel MRE seismic isolator. To evaluate and characterize the behavior of the MRE seismic isolator, experimental testing was conducted on a shake table facility under harmonic cycling loading. Experimental results show that the proposed adaptive seismic isolator can successfully alter the lateral stiffness and damping force in real time up to 37% and 45% respectively. Based on the successful development of the novel adaptive seismic isolator, a discussion is also extended to the impact and potential applications of such a device in structural control applications in civil engineering. © 2013 IOP Publishing Ltd.
Li, Y, Li, J, Tian, T & Li, W 2013, 'A highly adjustable magnetorheological elastomer base isolator for applications of real-time adaptive control', SMART MATERIALS AND STRUCTURES, vol. 22, no. 9, pp. 1-18.
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Inspired by its controllable and field-dependent stiffness/damping properties, there has been increasing research and development of magnetorheological elastomer (MRE) for mitigation of unwanted structural or machinery vibrations using MRE isolators or absorbers. Recently, a breakthrough pilot research on the development of a highly innovative prototype adaptive MRE base isolator, with the ability for real-time adaptive control of base isolated structures against various types of earthquakes including near- or far-fault earthquakes, has been reported by the authors. As a further effort to improve the proposed MRE adaptive base isolator and to address some of the shortcomings and challenges, this paper presents systematic investigations on the development of a new highly adjustable MRE base isolator, including experimental testing and characterization of the new isolator. A soft MR elastomer has been designed, fabricated and incorporated in the laminated structure of the new MRE base isolator, which aims to obtain a highly adjustable shear modulus under a medium level of magnetic field. Comprehensive static and dynamic testing was conducted on this new adaptive MRE base isolator to examine its characteristics and evaluate its performance. The experimental results show that this new MRE base isolator can remarkably change the lateral stiffness of the isolator up to 1630% under a medium level of magnetic field. Such highly adjustable MRE base isolator makes the design and implementation of truly real-time adaptive (e.g. semi-active or smart passive) seismic isolation systems become feasible. © 2013 IOP Publishing Ltd.
Li, Z, Wang, W, Wang, Y, Chen, F & Wang, Y 2013, 'Visual tracking by proto-objects', Pattern Recognition, vol. 46, no. 8, pp. 2187-2201.
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Lu, Y, Li, J, Ye, L & Wang, D 2013, 'Guided waves for damage detection in rebar-reinforced concrete beams', Construction and Building Materials, vol. 47, no. 1, pp. 370-378.
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The propagation properties of ultrasonic waves in rebar-reinforced concrete beams were investigated for the purpose of damage detection. Two types of piezoelectric (PZT) elements were used in experiments in which PZT disks were attached on the surfaces of concrete beams to observe wave propagation in concrete before and after a four-point bending test, while rectangular PZT patches were attached at the exposed ends of the rebar to monitor wave transmission along the rebar with and without simulated corrosion in the form of partial material removal from the rebar. Experimental testing demonstrated that the surface-attached PZT disks were capable of detecting the change in material properties due to the existence of cracking. In consideration of the inevitable discrepancies in different concrete beams due to specimen preparation and sensor installation, principal component analysis based on statistical parameters extracted from wave signals was applied to highlight the difference between benchmark and damaged rebar. The results show the potential of the principal components as damage indices for quantifying integrity conditions of concrete structures.
Luo, T, Qin, Z, Feng, X, Xia, F, Yao, Y & Sheng, D 2013, 'A symmetrisation method for non-associated unified hardening model', Computers and Geotechnics, vol. 52, pp. 38-45.
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Manap, MA, Sulaiman, WNA, Ramli, MF, Pradhan, B & Surip, N 2013, 'A knowledge-driven GIS modeling technique for groundwater potential mapping at the Upper Langat Basin, Malaysia', Arabian Journal of Geosciences, vol. 6, no. 5, pp. 1621-1637.
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Masihpour, M, Franklin, DR & Abolhasan, M 2013, 'Multihop Relay Techniques for Communication Range Extension in Near-Field Magnetic Induction Communication Systems.', J. Networks, vol. 8, no. 5, pp. 999-1011.
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In this paper, multihop relaying in RF-based communications and near field magnetic induction communication (NFMIC) is discussed. Three multihop relay strategies for NFMIC are proposed: Non Line of Sight Magnetic Induction Relay (NLoS-MI Relay), Non Line of Sight Master/Assistant Magnetic Induction Relay1 (NLoS-MAMI Relay1) and Non Line of Sight Master/Assistant Magnetic Induction Relay2 (NLoSMAMI Relay2). In the first approach only one node contributes to the communication, while in the other two techniques (which are based on a master-assistant strategy), two relaying nodes are employed. This paper shows that these three techniques can be used to overcome the problem of dead spots within a body area network and extend the communication range without increasing the transmission power and the antenna size or decreasing receiver sensitivity. The impact of the separation distance between the nodes on the achievable RSS and channel data rate is evaluated for the three techniques. It is demonstrated that the technique which is most effective depends on the specific network topology. Optimum selection of nodes as relay master and assistant based on the location of the nodes is discussed. The paper also studies the impact of the quality factor on achievable data rate. It is shown that to obtain the highest data rate, the optimum quality factor needs to be determined for each proposed cooperative communication method.
Mat, RC, Shariff, ARM, Pradhan, B, Mahmud, AR & Rahim, MSM 2013, 'An effective visualization and comparison of online terrain draped with multi-sensor satellite images', Arabian Journal of Geosciences, vol. 6, no. 12, pp. 4881-4889.
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Mohamed, AS, Lawal, B, Biswajeet, P, Shattri, M & Al-Sharif Abubakr, AA 2013, 'Modeling urban growth evolution and land-use changes using GIS based Cellular Automata and SLEUTH models: The case of Sana’a metropolitan city, Yemen', Environ Earth Sci, vol. 70, pp. 425-437.
Movassaghi, S, Abolhasan, M & Lipman, J 2013, 'A Review of Routing Protocols in Wireless Body Area Networks', Journal of Networks, vol. 8, no. 3, pp. 559-575.
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Recent technological advancements in wireless communication, integrated circuits and Micro-Electro-Mechanical Systems (MEMs) has enabled miniaturized, low-power, intelligent, invasive/ non-invasive micro and nano-technology sensor nodes placed in or on the human body for use in monitoring body function and its immediate environment referred to as Body Area Networks (BANs). BANs face many stringent requirements in terms of delay, power, temperature and network lifetime which need to be taken into serious consideration in the design of different protocols. Since routing protocols play an important role in the overall system performance in terms of delay, power consumption, temperature and so on, a thorough study on existing routing protocols in BANs is necessary. Also, the specific challenges of BANs necessitates the design of new routing protocols specifically designed for BANs. This paper provides a survey of existing routing protocols mainly proposed for BANs. These protocols are further classified into five main categories namely, temperature based, cross-layer, cluster based, cost-effective and QoS-based routing, where each protocol is described under its specified category. Also, comparison among routing protocols in each category is given. © 2013 ACADEMY PUBLISHER.
Nguyen, VT, Rujikiatkamjorn, C & Indraratna, B 2013, 'Analytical Solutions for Filtration Process Based on Constriction Size Concept', Journal of Geotechnical and Geoenvironmental Engineering, vol. 139, no. 7, pp. 1049-1061.
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Ni, J, Indraratna, B, Geng, X-Y, Carter, JP & Rujikiatkamjorn, C 2013, 'Radial consolidation of soft soil under cyclic loads', Computers and Geotechnics, vol. 50, pp. 1-5.
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Oberst, S, Lai, JCS & Marburg, S 2013, 'Guidelines for numerical vibration and acoustic analysis of disc brake squeal using simple models of brake systems', Journal of Sound and Vibration, vol. 332, no. 9, pp. 2284-2299.
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Oberst, SM & Lai, JCS 2013, 'The role of pad-modes and nonlinearity in instantaneous mode squeal', The Journal of the Acoustical Society of America, vol. 133, no. 5_Supplement, pp. 3462-3462.
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Disc brake squeal is a major source of customer dissatisfaction and related warranty costs for automobile manufacturers. Although mode coupling is recognized as a mechanism often found in squealing brakes, recent research results show that friction induced pad-mode instabilities could be the cause of instantaneous mode squeal reported in the literature. In this paper, the nonlinear characteristics of instantaneous mode squeal initiated by pad-mode instabilities are studied by analyzing phase space plots of vibrations and sound pressure for a numerical model of a pad-on-plate system as the friction coefficient increases. Results show that as the friction coefficient increases from 0.05 to 0.65, attractors of vibration in the phase space transits from limit cycle to quasi-periodic, showing signs of approaching chaotic behavior. It is shown here that the correlation of the sound pressure behavior in the phase-space with structural vibration is crucial to understanding the role of pad modes and nonlinearity in instantaneous mode squeal.
Pal, S, Pal, U & Blumenstein, M 2013, 'Off‐line verification technique for Hindi signatures', IET Biometrics, vol. 2, no. 4, pp. 182-190.
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Handwritten signature is one of the oldest biometric attributes used for authentication of an individual or a document. The purpose of this study is to present an empirical contribution towards the understanding of signature verification using a novel method involving off-line Hindi (Devnagari) signatures. Although research in the field of signature verification involving Western signatures has been well studied, there has been relatively little attention devoted to non-Western signatures such as Chinese, Japanese, Arabic, Persian etc. In this study, the performance of an off-line signature verification system involving Hindi signatures, whose style is distinct from Western scripts, was investigated. The gradient feature, Zernike moment features and SVMs were considered for verification. To the best of the authors' knowledge, Hindi signatures investigated as part of a large dataset have never been used for the task of signature verification, and this research work is only the second important report using Hindi signatures in this area. An encouraging accuracy of 90.69% was obtained using gradient feature. The Hindi signature database employed for experimentation consisted of 2400 (100 × 24) genuine signatures and 3000 (100 × 30) forgeries. The error rates of 11.50% FRR and 7.12% FAR were obtained through experimentation using gradient features. © The Institution of Engineering and Technology 2013.
Pirasteh, S, Pradhan, B, Safari, HO & Ramli, MF 2013, 'Coupling of DEM and remote-sensing-based approaches for semi-automated detection of regional geostructural features in Zagros mountain, Iran', Arabian Journal of Geosciences, vol. 6, no. 1, pp. 91-99.
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Pourghasemi, H, Pradhan, B, Gokceoglu, C & Moezzi, KD 2013, 'A comparative assessment of prediction capabilities of Dempster–Shafer and Weights-of-evidence models in landslide susceptibility mapping using GIS', Geomatics, Natural Hazards and Risk, vol. 4, no. 2, pp. 93-118.
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Pourghasemi, HR, Jirandeh, AG, Pradhan, B, Xu, C & Gokceoglu, C 2013, 'Landslide susceptibility mapping using support vector machine and GIS at the Golestan Province, Iran', Journal of Earth System Science, vol. 122, no. 2, pp. 349-369.
POURGHASEMI, HR, JIRANDEH, AG, PRADHAN, B, XU, C & GOKCEOGLU, C 2013, 'Landslide susceptibility mapping using support vector machine and GIS at the Golestan Province, Iran', Journal of Earth System Science, vol. 122, no. 2, pp. 349-369.
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Pourghasemi, HR, Pradhan, B, Gokceoglu, C, Mohammadi, M & Moradi, HR 2013, 'Application of weights-of-evidence and certainty factor models and their comparison in landslide susceptibility mapping at Haraz watershed, Iran', Arabian Journal of Geosciences, vol. 6, no. 7, pp. 2351-2365.
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Pourghasemi, HR, Pradhan, B, Moradi, HR, Mohammady, M & Bednarik, M 2013, 'A Comparative Assessment Between Index of Entropy, Logistic Regression, and Frequency Ratio Models for Landslide Susceptibility Mapping in Iran'.
Pradhan, B 2013, 'A comparative study on the predictive ability of the decision tree, support vector machine and neuro-fuzzy models in landslide susceptibility mapping using GIS', Computers & Geosciences, vol. 51, pp. 350-365.
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Pradhan, B, Lee, S & Buchroithner, MF 2013, 'Pradhan et al. 2010-CEUS-FullCitation'.
Pradhan, B, Mansor, S, Abdul-Hadi, A & Tan, CK 2013, 'Seasonal variability of chlorophyll-a and oceanographic conditions in Sabah waters in relation to Asian monsoona remote sensing study', Environmental Monitoring and Assessment, vol. 185, no. 2013, p. 3977.
Pradhan, B, Mansor, S, Al-shalabi, M, Althuwaynee, OF & Billa, L 2013, 'Manifestation of Remote Sensing Data in Modeling Urban Sprawl Using the SLEUTH Model and Brute Force Calibration: A Case Study of Sanaa City, Yemen.', Journal of the Indian Society of Remote Sensing, vol. 41, no. 2, pp. 405-416.
Pradhan, B, Tehrany, MS & Jebur, MN 2013, 'Spatial prediction of flood susceptible areas using rule based decision tree (DT) and ensemble bivariate and multivariate statistical models in GIS', Journal of Hydrology, vol. 504, no. 2013, pp. 69-79.
Regmi, AD, Yoshida, K, Nagata, H, Pradhan, AMS, Pradhan, B & Pourghasemi, HR 2013, 'The relationship between geology and rock weathering on the rock instability along Mugling–Narayanghat road corridor, Central Nepal Himalaya', Natural Hazards, vol. 66, no. 2, pp. 501-532.
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Ross, P & Blumenstein, M 2013, 'Cloud computing: the nexus of strategy and technology', Journal of Business Strategy, vol. 34, no. 4, pp. 39-47.
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PurposeThe purpose of this paper is to analyse the impact of Cloud technologies on management practices and business strategies. It considers the role of human resource management (HRM) departments in supporting the organisational changes required for the introduction and integration of Cloud business strategies.Design/methodology/approachThe study uses a qualitative exploratory research approach. It utilises the resource view of the firm and transaction costs economics (TCE) to support the analysis. It synthesises the literature with the qualitative interview data.FindingsCloud business models require organisations to focus on the nexus of business strategies and information and communication technology (ICT) capabilities. HRM departments can play a positive role in this process by better integrating ICT sections into business decision‐making processes. Cloud technologies may further change ICT worker functions and roles.Research limitations/implicationsQualitative research approaches may limit the generality of the findings. However they allowed for an in‐depth analysis of complex Cloud related data that quantitative approaches may not have elicited.Practical implicationsThe paper outlines a strategic “holistic” approach for organisations shifting to Cloud‐based business models.Social implications
Rujikiatkamjorn, C & Indraratna, B 2013, 'Current state of the art in vacuum preloading for stabilising soft soil', Geotechnical Engineering, vol. 44, no. 4, pp. 77-87.
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In this paper the analytical solutions for radial consolidation that include time dependent surcharge loading and vacuum pressure are proposed, whilst also considering the impact of the parabolic variation of permeability in the smear zone. The use of the spectral method for multilayered soil consolidation is introduced and verified. The Elliptical Cavity Expansion Theory is used to predict the extent of soil disturbance (smear zone) caused by the installation of mandrel driven vertical drains. The predicted smear zone is then compared to the data obtained from large-scale radial consolidation tests. Furthermore, the advantages and limitations of applying a vacuum through vertical drains are discussed using the proposed solutions. The vacuum pressure applied generates a negative pore water pressure that increases the effective stress within the soil, which leads to an accelerated consolidation. Vacuum pressure is modelled as a distributed negative pressure (suction) along the length of the drain and across the surface of the soil. Analytical and numerical analyses that incorporate the Authors' equivalent plane strain solution are conducted to predict the excess pore pressures, lateral and vertical displacement. The application of the theoretical models for selected case histories at the site of the 2nd Bangkok International Airport and the Port of Brisbane, are discussed and analysed. The predictions are compared with the available field data and show that the proposed model can be confidently used to predict the performance with acceptable accuracy through rigorous mathematical modelling and numerical analysis. The research findings verify that the role of the smear zone and vacuum distribution can significantly affect the consolidation of soil, but these aspects need to be modelled appropriately to obtain reliable.
RUJIKIATKAMJORN, C, ARDANA, MDW, INDRARATNA, B & LEROUEIL, S 2013, 'Conceptual model describing smear zone caused by mandrel action', Géotechnique, vol. 63, no. 16, pp. 1377-1388.
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In this study the characteristics and extent of the smear zone are investigated using a large, undisturbed sample. The aim of using such a sample is to capture the realistic characteristics of the smear zone in relation to the in situ soil structure during the installation of prefabricated vertical drains (PVDs) using a mandrel. The extent of the smear zone for Bulli clay (New South Wales, Australia) is determined on the basis of normalised permeability (kh/khu) and the reduction in the water content upon consolidation. The permeability and compressibility of the soil are investigated to determine the extent to which the soil surrounding the PVD has become disturbed. In laboratory testing, the soil consolidation behaviour due to a PVD is studied using a large-scale consolidometer apparatus. The numerical results have shown that the writers' solutions give excellent agreement with laboratory observations.
Rujikiatkamjorn, C, Indraratna, B & Chiaro, G 2013, 'Compaction of coal wash to optimise its utilisation as water-front reclamation fill', Geomechanics and Geoengineering, vol. 8, no. 1, pp. 36-45.
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The coal mining industry in and around Wollongong, New South Wales, Australia, is responsible for producing an ever growing quantity of coal washery reject materials and other mine waste aggregates. Considerable effort is being undertaken to reuse, beneficially, these waste products in the immediate suburbs of Wollongong. In this paper, detailed laboratory investigations carried out on coal wash (i.e. coarse coal washery reject), produced at Dendrobium coal mine near Wollongong, are presented. Geotechnical tests were conducted to determine the particle size distribution, compaction characteristics, shear resistance and collapse potential. Compaction tests were performed under dry and submerged conditions to examine comprehensively the compactability and the strength properties of coal wash. The laboratory tests show that, if properly compacted, Dendrobium coal wash has a good potential as effective low-porosity fill for embankments and port reclamation. © 2013 Copyright Taylor and Francis Group, LLC.
Safari, HO, Pirasteh, S, Pradhan, B & Amid, H 2013, 'Geohazards analysis of Pisa tunnel in a fractured incompetent rocks in Zagros Mountains, Iran', Arabian Journal of Geosciences, vol. 6, no. 4, pp. 1101-1112.
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Sezer, EA, Pradhan, B & Gokceoglu, C 2013, 'Erratum to', Expert Systems with Applications: An International Journal, vol. 40, no. 6, p. 2360.
Sezer, EA, Pradhan, B & Gokceoglu, C 2013, 'Erratum to: “Manifestation of an adaptive neuro-fuzzy model on landslide susceptibility mapping: Klang valley, Malaysia” [Expert Systems with Applications 38 (2011) 8208–8219]', Expert Systems with Applications, vol. 40, no. 6, pp. 2360-2360.
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Sheng, D, Cui, L & Ansari, Y 2013, 'Interpretation of Cone Factor in Undrained Soils via Full-Penetration Finite-Element Analysis', International Journal of Geomechanics, vol. 13, no. 6, pp. 745-753.
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Sheng, D, Zhang, S & Yu, Z 2013, 'Unanswered questions in unsaturated soil mechanics', Science China Technological Sciences, vol. 56, no. 5, pp. 1257-1272.
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Sheng, D, Zhang, S, Yu, Z & Zhang, J 2013, 'Assessing frost susceptibility of soils using PCHeave', Cold Regions Science and Technology, vol. 95, pp. 27-38.
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Sheng, DC, Zhang, S & Li, X 2013, 'Effects of train loads on frost heave of embankments', Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering, vol. 35, no. 12, pp. 2186-2191.
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Substantial frost heave is observed in coarse fills in high-speed railway embankment. These coarse fills have very low water content and are located above the groundwater. In an attempt to explain the unexpected frost heave, it is proposed that the cyclic train loads cause the development of the excess pore water pressure in the underlying subgrade soils and hence 'pump' up the water to the frost front, which in turn feeds the formation of ice and results in continuous frost heave. A simple quantitative model is developed to simulate the pumping-enhanced frost heave. The numerical results show that the proposed mechanism can indeed provide a legitimate explanation for the otherwise unexpected frost heave. The engineering implications of this new frost heave mechanism are also discussed, in the context of designing frost heave mitigation measures in seasonally frozen regions.
Subhani, M, Li, J & Samali, B 2013, 'A comparative study of guided wave propagation in timber poles with isotropic and transversely isotropic material models', Journal of Civil Structural Health Monitoring, vol. 3, no. 2, pp. 65-79.
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Subhani, M, Li, JC, Gravenkamp, H & Samali, B 2013, 'Effect of Elastic Modulus and Poisson's Ratio on Guided Wave Dispersion Using Transversely Isotropic Material Modelling', Advanced Materials Research, vol. 778, pp. 303-311.
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Timber poles are commonly used for telecommunication and power distribution networks, wharves or jetties, piling or as a substructure of short span bridges. Most of the available techniques currently used for non-destructive testing (NDT) of timber structures are based on one-dimensional wave theory. If it is essential to detect small sized damage, it becomes necessary to consider guided wave (GW) propagation as the behaviour of different propagating modes cannot be represented by one-dimensional approximations. However, due to the orthotropic material properties of timber, the modelling of guided waves can be complex. No analytical solution can be found for plotting dispersion curves for orthotropic thick cylindrical waveguides even though very few literatures can be found on the theory of GW for anisotropic cylindrical waveguide. In addition, purely numerical approaches are available for solving these curves. In this paper, dispersion curves for orthotropic cylinders are computed using the scaled boundary finite element method (SBFEM) and compared with an isotropic material model to indicate the importance of considering timber as an anisotropic material. Moreover, some simplification is made on orthotropic behaviour of timber to make it transversely isotropic due to the fact that, analytical approaches for transversely isotropic cylinder are widely available in the literature. Also, the applicability of considering timber as a transversely isotropic material is discussed. As an orthotropic material, most material testing results of timber found in the literature include 9 elastic constants (three elastic moduli and six Poisson's ratios), hence it is essential to select the appropriate material properties for transversely isotropic material which includes only 5 elastic constants. Therefore, comparison between orthotropic and transversely isotropic material model is also presented in this article to reveal the effect of elastic moduli and Pois...
Tabatabaiefar, SHR, Fatahi, B & Samali, B 2013, 'Lateral seismic response of building frames considering dynamic soil-structure interaction effects', STRUCTURAL ENGINEERING AND MECHANICS, vol. 45, no. 3, pp. 311-321.
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In this study, to have a better judgment on the structural performance, the effects of dynamic Soil-Structure Interaction (SSI) on seismic behaviour and lateral structural response of mid-rise moment resisting building frames are studied using Finite Difference Method. Three types of mid-rise structures, including 5, 10, and 15 storey buildings are selected in conjunction with three soil types with the shear wave velocities less than 600m/s, representing soil classes Ce, De and Ee, according to Australian Standard AS 1170.4. The above mentioned frames have been analysed under two different boundary conditions: (i) fixed-base (no soil-structure interaction), and (ii) flexible-base (considering soil-structure interaction). The results of the analyses in terms of structural lateral displacements and drifts for the above mentioned boundary conditions have been compared and discussed. It is concluded that the dynamic soil-structure interaction plays a considerable role in seismic behaviour of mid-rise building frames including substantial increase in the lateral deflections and inter-storey drifts and changing the performance level of the structures from life safe to near collapse or total collapse. Thus, considering soil-structure interaction effects in the seismic design of mid-rise moment resisting building frames, particularly when resting on soft soil deposit, is essential.
Tabatabaiefar, SHR, Fatahi, B & Samali, B 2013, 'Seismic Behavior of Building Frames Considering Dynamic Soil-Structure Interaction', INTERNATIONAL JOURNAL OF GEOMECHANICS, vol. 13, no. 4, pp. 409-420.
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The seismic excitation experienced by structures is a function of the earthquake source, travel path effects, local site effects, and soilstructure interaction (SSI) influences. The result of the first three of these factors is referred to as free-field ground motion. The structural response to free-field motion is influenced by the SSI. In particular, accelerations within structures are affected by the flexibility of the foundation support and variations between the foundation and free-field motions. Consequently, an accurate assessment of inertial forces and displacements in structures can require a rational treatment of SSI effects. In the current study, to depict these effects on the seismic response of moment-resisting building frames, a 10-story moment-resisting building frame resting on a shallow foundation was selected in conjunction with three soil types with shear-wave velocities of less than 600 m/s, representing Soil Classes Ce, De, and Ee according to an existing Australian Standard. The structural sections were designed after applying dynamic nonlinear time-history analysis, based on both the elastic method, and inelastic procedure using the elastic-perfectly plastic behavior of the structural elements. The frame sections were modeled and analyzed using the finite-difference method andthe FLAC 2D software under two different boundary conditions: (1) fixed-base (no SSI) and (2) considering the SSI. Fully nonlinear dynamic analysis under the influence of various earthquake records was conducted and the results of the two different cases for elastic and inelastic behavior of the structuralmodel were extracted, compared, and discussed. The results indicate that the performance level of themodel resting on Soil Class Ce does not change substantially and remains in the life safe level while the performance level of themodel resting on Soil Classes De and Ee substantially increase from the life safe level to near collapse for both elastic and ine...
Tehrany, MS, Pradhan, B & Jebur, MN 2013, 'Remote Sensing Data Reveals Eco-Environmental Changes in Urban Areas of Klang Valley, Malaysia: Contribution from Object Based Analysis', Journal of the Indian Society of Remote Sensing, vol. 41, no. 4, pp. 981-991.
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Tehrany, MS, Pradhan, B & Jebur, MN 2013, 'Spatial prediction of flood susceptible areas using rule based decision tree (DT) and a novel ensemble bivariate and multivariate statistical models in GIS', Journal of Hydrology, vol. 504, pp. 69-79.
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Teng, PSP, Leong, KF, Kong, PW, Halkon, BJ & Huang, PY 2013, 'The use of rapid prototyping in the design of a customised ankle brace structure for ACL injury risk reduction', Virtual and Physical Prototyping, vol. 8, no. 4, pp. 241-247.
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Rapid prototyping, or additive manufacturing, is becoming more useful in creating functional prototypes, especially when customisation is required. This paper explores the use of three-dimensional (3D) printing in designing a customised ankle brace structure for anterior cruciate ligament (ACL) injury risk reduction. A new process is proposed to obtain ankle flexion angles and the corresponding foot surface strain associated with high ACL injury risks through motion analysis. This data is used in the design of the customised ankle brace structure and printed using rapid prototyping. One customised ankle brace structure was printed and tested to demonstrate this proposed framework. The ankle flexion range of motion (ROM) was significantly reduced in the high-risk ankle positions with the ankle brace structure. Rapid prototyping could thus be used to design customised ankle brace structures and this is useful in reducing fabrication time and complexity of customisation. © 2013 Taylor & Francis.
THAKUR, PK, VINOD, JS & INDRARATNA, B 2013, 'Effect of confining pressure and frequency on the deformation of ballast', Géotechnique, vol. 63, no. 9, pp. 786-790.
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Increasing the speed and frequency of trains with the same static axle weight imparts higher dynamic axle loads more frequently. When this occurs on existing track which has not been designed for such loading there can be increased rates of ballast degradation, characterised by unacceptable deformation and lateral spread, leading to more frequent requirements for track maintenance. Recent studies carried out at the University of Wollongong highlighted that confining pressure and frequency have a significant influence on the permanent deformation and degradation of ballast. However, confinement required to keep the deformation and degradation of the ballasted track to an acceptable limit will depend on the train speed (frequency). In this context, a series of cyclic triaxial tests was conducted on latite basalt samples having an initial confining pressure of 120 kPa. After every 25 000 cycles, the confining pressure was decreased in steps to simulate the drop of confining pressure during heavy traffic. This test procedure was adopted to replicate the influence of train speed on the stability of ballast. Test results indicated that both the frequency and confining pressure have a significant influence on the permanent deformation of ballast. Resilient modulus is found to increase with an increase in confining pressure and number of cycles, but to decrease with increasing frequency. The results also showed that the ballast layer requires a minimum level of confinement for preventing an excessive amount of track deformation. An empirical equation is formulated to determine the required confining pressure and resilient modulus of the ballast layer for an allowable limit of track deformation at a given train speed.
Tien Bui, D, Pradhan, B, Lofman, O, Revhaug, I & Dick, ØB 2013, 'Regional prediction of landslide hazard using probability analysis of intense rainfall in the Hoa Binh province, Vietnam', Natural Hazards, vol. 66, no. 2, pp. 707-730.
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Wang, L, Luo, Z & Juang, CH 2013, 'Foundation Engineering in the Face of Uncertainty', Geotechnical Special Publication, no. 229, pp. 530-541.
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In this paper, an efficient framework based on the maximum likelihood principle for inverse analysis of soil parameters in braced excavations is proposed. With this framework, the observed maximum ground settlement and maximum wall deflection are used to back-calculate soil parameters through a semi-empirical model. The updated soil parameters from the current stage of excavation can be used to predict the maximum ground settlement and maximum wall deflection in the subsequent stages of excavations. The proposed framework is computationally efficient and can easily be implemented in a spreadsheet. The effectiveness of the proposed framework is illustrated with a well documented excavation case. The results of the case study show that the updated soil parameters improve the accuracy of predictions of the wall and ground responses in a braced excavation. © 2013 American Society of Civil Engineers.
Wi, HJ, Lee, JH, Blumenstein, M, Guan, H & Loo, YC 2013, 'Development of Methodology for Enhancing Visual Bridge Condition Assessment Using Image Processing Techniques', Applied Mechanics and Materials, vol. 256-259, no. PART 1, pp. 1563-1570.
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Many bridge authorities have implemented Bridge Information Systems (BISs) or Bridge Management Systems (BMSs) to effectively manage their routine inspection information. The success of a BMS is highly dependent on the quality of bridge inspection outcomes and accurate estimation of future bridge condition ratings. To ensure such successful outcomes, a BMS must (1) contain reliable, consistent and accurate condition data from routine bridge inspections; and (2) encompass reliable deterioration modelling that overcomes the shortcomings of a lack of historical bridge inspection records. However published literature demonstrates that several limitations exist particularly in terms of inconsistency of inspection outcomes due to subjective judgment. To minimise such limitations, this paper presents a feasibility study for the enhancement of the current visual bridge inspection method using optical image processing techniques. The development work consists of image processing and knowledge-based approaches. It is anticipated that the proposed method is capable of minimising the shortcomings of subjective judgment on condition rating assessment and providing cost effective solutions to bridge agencies. Ultimately, the proposed bridge inspection methodology can provide consistent and accurate evaluation on the condition states of bridge elements. This in turn will lead to more reliable predictions of long-term bridge performance.
Yang, C, Sheng, D, Carter, JP & Huang, J 2013, 'Stochastic Evaluation of Hydraulic Hysteresis in Unsaturated Soils', Journal of Geotechnical and Geoenvironmental Engineering, vol. 139, no. 7, pp. 1211-1214.
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Yang, J, Du, H, Li, W, Li, Y, Li, J, Sun, S & Deng, HX 2013, 'Experimental study and modeling of a novel magnetorheological elastomer isolator', SMART MATERIALS AND STRUCTURES, vol. 22, no. 11, pp. 1-14.
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This paper reports an experimental setup aiming at evaluating the performance of a newly designed magnetorheological elastomer (MRE) seismic isolator. As a further effort to explore the field-dependent stiffness/damping properties of the MRE isolator, a series of experimental testing were conducted. Based upon the analysis of the experimental responses and the characteristics of the MRE isolator, a new model that is capable of reproducing the unique MRE isolator dynamics behaviors is proposed. The validation results verify the model's effectiveness to portray the MRE isolator. A study on the field-dependent parameters is then provided to make the model valid with fluctuating magnetic fields. To fully explore the mechanism of the proposed model, an investigation relating the dependence of the proposed model on every parameter is carried out. © 2013 IOP Publishing Ltd.
Zare, M, Pourghasemi, HR, Vafakhah, M & Pradhan, B 2013, 'Landslide susceptibility mapping at Vaz Watershed (Iran) using an artificial neural network model: a comparison between multilayer perceptron (MLP) and radial basic function (RBF) algorithms', Arabian Journal of Geosciences, vol. 6, no. 8, pp. 2873-2888.
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Zeng, J, Guo, Y, Li, Y, Zhu, J & Li, J 2013, 'Two-dimensional magnetic property measurement for magneto-rheological elastomer', JOURNAL OF APPLIED PHYSICS, vol. 113, no. 17.
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Zhang, J, Xu, YL, Li, J, Xia, Y & Li, JC 2013, 'Statistical moment-based structural damage detection method in time domain', Earthquake Engineering and Engineering Vibration, vol. 12, no. 1, pp. 13-23.
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A novel structural damage detection method with a new damage index, i.e., the statistical moment-based damage detection (SMBDD) method in the frequency domain, has been recently proposed. The aim of this study is to extend the SMBDD method in the frequency domain to the time domain for building structures subjected to non-Gaussian and non-stationary excitations. The applicability and effectiveness of the SMBDD method in the time domainis verified both numerically and experimentally. Shear buildings with various damage scenarios are fi rst numerically investigated in the time domain taking into account the effect of measurement noise. The applicability of the proposed method in the time domain to building structures subjected to non-Gaussian and non-stationary excitations is then experimentally investigated through a series of shaking table tests, in which two three-story shear building models with four damage scenarios aretested. The identifi ed damage locations and severities are then compared with the preset values. The comparative results are found to be satisfactory, and the SMBDD method is shown to be feasible and effective for building structures subjected to non-Gaussian and non-stationary excitations.
Zhang, X, Krabbenhoft, K, Pedroso, DM, Lyamin, AV, Sheng, D, da Silva, MV & Wang, D 2013, 'Particle finite element analysis of large deformation and granular flow problems', Computers and Geotechnics, vol. 54, pp. 133-142.
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Al-Sharif, AAA, Pradhan, B, Hadi, SJ & Mola, N 1970, 'Revisiting methods and potentials of SAR change detection', Lecture Notes in Engineering and Computer Science, pp. 2231-2237.
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Change detection is one of the important applications in earth environment observation, risk management and security. Synthetic Aperture Radar (SAR) provides a dependable and valuable source of information for monitoring changes and change detection applications. In this work, different methods and different SAR data that used in change detection application and factors which effect on this application have been studied. It has been found that the use of SAR data in monitoring and detecting changes is beneficial and advantageous; especially if SAR data integrated with optical data. Combination of methods and considering target conditions and other factors, overcomes the deficiencies that affect the use of SAR data in change detection. The use of combination technique gives an indication that we can combine other methods to enhance monitoring changes based on study area conditions; also we can develop new algorithms based on which combination would be used.
Althuwaynee, OF & Pradhan, B 1970, 'Ensemble of statistical EBF into a knowledge based AHP for slope failures mapping', 34th Asian Conference on Remote Sensing 2013, ACRS 2013, pp. 3485-3492.
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Landslide susceptibility mapping is still considered as a hot research topic, due to its disastrous impact worldwide. Over the years, traditional GIS based Analytic Hierarchy Process (AHP) model has been popularly used to address this problem. Unfortunately, due to the subjectivity of the expert opinion in AHP model, a semi- quantitative model is always needed. In this study, an ensemble model is proposed using both evidential belief function (EBF) and AHP model. The study shows an innovative methodology to predict rainfall-induced susceptibility map in Kuala Lumpur city and surrounding areas using geographic information system (GIS). For inventory mapping, a total of 220 landslide locations were collected using historical landslide location data. The landslide location data was then used for training various landslide conditioning factors such as; a topographic derived parameters, lithology, NDVI, landuse and landcover maps. An area under the curve (AUC) of ensemble model showed 84% success rate accuracy, whereas in the case of EBF, it showed 82% accuracy. On the other hand, ensemble prediction rate showed 82% and EBF showed 75% prediction accuracy respectively. The newly developed ensemble model produced a reasonable accuracy in landslide susceptibility mapping for the study area. The final result can provide a valuable scientific basis for spatial decision making in planning and urban management studies. Copyright © (2013) by the Asian Association on Remote Sensing.
Askari, M, Li, J & Samali, B 1970, 'A Multi-objective Subtractive FCM Based TSK Fuzzy System with Input Selection, and Its Application to Dynamic Inverse Modelling of MR Dampers', Lecture Notes in Computer Science, International Conference on Artificial Intelligence and Soft Computing, Springer Berlin Heidelberg, Zakopane, POLAND, pp. 215-226.
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A new encoding scheme is presented for a fuzzy-based nonlinear system identification methodology, using the subtractive Fuzzy C-Mean clustering and a modified version of non-dominated sorting genetic algorithm. This method is able to automatically select the best inputs as well as the structure of the fuzzy model such as rules and membership functions. Moreover, three objective functions are considered to satisfy both accuracy and compactness of the model. The proposed method is then employed to identify the inverse model of a highly nonlinear structural control device, namely Magnetorheological (MR) damper. It is shown that the developed evolving TakagiSugeno-Kang (TSK) fuzzy model can identify and grasp the nonlinear dynamics of inverse systems very well, while a small number of inputs and fuzzy rules are required for this purpose.
Athukorala, R, Indraratna, B & Vinod, JS 1970, 'Modeling the Internal Erosion Behavior of Lignosulfonate Treated Soil', Geo-Congress 2013, Geo-Congress 2013, American Society of Civil Engineers, pp. 1872-1881.
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This paper presents the development of an analytical model to predict the erosion rate of stabilised soil based on the law of conservation of energy. The model incorporates the strain energy intensity until failure, obtained from the stress-strain curves of lignosulfonate treated soil, to account for the stabilisation. The novel approach of this model is to correlate the shear strength characteristics with the erosion resistance. The proposed equation was used to predict the erosion rates of a non-plastic silty sand treated with lignosulfonate. The erosion resistance was interpreted in terms of the coefficient of soil erosion and the critical shear stress initiating erosion. It was observed that with the increasing amount of lignosulfonate, the critical shear stress increases and the coefficient of soil erosion decreases. The proposed model predicts the erosion resistant behaviour of lignosulfonate treated soil similar to the laboratory experiments. © 2013 American Society of Civil Engineers.
Azari, B, Fatahi, B & Khabbaz, H 1970, 'Long-term Viscoplastic Behaviour of Embankments Built on Improved Soft Soil Using Vertical Drains', Geo-Congress 2013, Geo-Congress 2013, American Society of Civil Engineers, San Diego, California, pp. 2124-2132.
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In this paper, a nonlinear elastic visco-plastic model is incorporated in the general consolidation equation to investigate the time dependent performance of embankments constructed over deep soft soil deposits stabilised with prefabricated vertical drains (PVDs) and preloading. To model vertical and radial consolidation processes, a finite difference formulation is implemented for fully coupled axisymmetric consolidation. The developed numerical model is validated against Väsby test fill with the available long-term settlement monitoring results for the soft clay deposit improved with PVDs assisted preloading. Practicing engineers can adopt the developed code and guidelines to predict the long term performance of embankments on soft soil consolidated using preloading. © 2013 American Society of Civil Engineers.
Baro, EN, Oberst, S, Lai, JCS & Evans, TA 1970, 'A signal processing method for extracting vibration signals due to ants' activities', 42nd International Congress and Exposition on Noise Control Engineering 2013, INTER-NOISE 2013: Noise Control for Quality of Life, International Congress and Exposition on Noise Control Engineering, Innsbruck, Austria, pp. 3631-3640.
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Many software algorithms have been developed to track ants by analysing recorded videos. On the other hand, the feasibility of using vibrations measured at the substrate to classify ants' behaviour has not been examined before. A method is developed to separate vibrations owing to ants' activities from the substrate's response through a filtering/de-convolution procedure. This involves estimating the frequency response of the substrate and applying wavelet analysis to the measured vibrations. A number of responses due to ants' behaviours have been observed: Ants shaking, falling, carrying stones, walking, scratching/biting, tapping hind legs, grooming, and antennation/feeding. Vibrations produced by ants falling, carrying stones, walking and scratching/biting are measurable (i.e, above background noise levels). The proposed method is shown to be successful in classifying activities due to ants falling, ants carrying stones and to a lesser extent ants' scratching/biting. With further refinement, it seems feasible to use vibrations and the proposed algorithm to measure ants' behaviours in bioassays. Copyright© (2013) by Austrian Noise Abatement Association (OAL).
Barua, B, Abolhasan, M, Franklin, DR, Safaei, F & IEEE 1970, 'Outage Probability of Multihop Relay Networks', 2013 9TH INTERNATIONAL WIRELESS COMMUNICATIONS AND MOBILE COMPUTING CONFERENCE (IWCMC), IEEE International Conference on Wireless and Mobile Computing, Networking and Communications, IEEE, Sardinia, Italy, pp. 456-460.
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In this paper we analyze the outage performance of a multihop cooperative relay network where relays in the system can change positions dynamically and use all possible links to forward the message to the next hop over Rayleigh fading channels. We derive the general closed form expression of outage probability and asymptotic coding gain of the network.
Barua, B, Abolhasan, M, Franklin, DR, Safaei, F & IEEE 1970, 'SEP of Multihop Relay Networks in Nakagami-m Fading Channels', 2013 IEEE 78TH VEHICULAR TECHNOLOGY CONFERENCE (VTC FALL), IEEE Vehicular Technology Conference, IEEE, Las Vegas, NV, USA, pp. 1-5.
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In this paper we analyze the error performance of a cooperative multihop parallel relay network over Nakagamim fading channels using M-ary Phase-shift keying (MPSK) modulation. We derive the general closed form expression of the symbol error probability (SEP) and present numerical results on the performance of the network. Copyright © 2013 by the Institute of Electrical and Electronic Engineers, Inc.
Burton, GJ, Sheng, D & Romero, E 1970, 'State surface of wetting-drying cycles at the equilibrium stage', ADVANCES IN UNSATURATED SOILS, 1st Pan-American Conference on Unsaturated Soils, CRC Press, Los Andes Univ, Cartagena de Indias, COLOMBIA, pp. 449-454.
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Cai, G, Sheng, D, Sloan, S & Zhao, C 1970, 'Preliminary Study on Modeling Thermo-Hydro-Mechanical Coupling Behavior of Unsaturated Soils Based on Hybrid Mixture Theory', Poromechanics V, Fifth Biot Conference on Poromechanics, American Society of Civil Engineers, pp. 1444-1453.
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Thermo-hydro-mechanical (THM) coupling processes in unsaturated soils are very important in both theoretical and engineering applications. A coupled formulation based on hybrid mixture theory is derived to model the THM coupling behavior of unsaturated soils. The free-energy and dissipative functions for different phases are derived from the Taylor's series expansions. Constitutive relationships of the THM coupled behavior for unsaturated soils, which include deformation, entropy change, fluid flow, heat conduction, and dynamic compatibility conditions on the interfaces are then established. The number of field equations is shown to be equal to the number of unknown variables; thus, a closed problem is formed. In addition to the modification of the physical conservation equations with coupling effect terms, the constitutive equations, which consider the coupling of elastoplastic deformation of the soil skeleton, fluid flow, and heat transfer, are derived. © 2013 American Society of Civil Engineers.
Chen, J, Cao, J, Abawajy, J, Mauri, JL, Bennamoun, M, Goscinski, A, Blumenstein, M, Wei, D & Yang, LT 1970, 'Message from CIT2013 Chairs', 2013 IEEE 16th International Conference on Computational Science and Engineering, 2013 IEEE 16th International Conference on Computational Science and Engineering (CSE), IEEE, p. 23.
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Chen, JY, Ummin, O, Yu, T & Qi, YJ 1970, 'Applications of Rayleigh Wave Detection Technique and Polymer Grouting Technology in Waterproof Construction', Applied Mechanics and Materials, 2nd International Conference on Civil, Architectural and Hydraulic Engineering (ICCAHE 2013), Trans Tech Publications, Ltd., Zhuhai, PEOPLES R CHINA, pp. 748-754.
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The underground water seepage is always the key and difficult point in waterproof engineering. Aiming at the characteristics of underground engineering waterproof, this paper describes how to make use of Rayleigh wave detection technology to detect leakage in underground works, and find disease location through the analysis of the dispersion curve, and then combine Rayleigh wave detection technology with polymer grouting technique grouting on the disengaging position, to achieve the effect of waterproof plugging. Research results show that through combining Rayleigh wave detection technique and the combination of polymer grouting technology, it is quicker and more convenient to manage underground leakage defects, which satisfies the project need and has wide application value and social benefits.
Conway, D, Dick, I, Li, Z, Wang, Y & Chen, F 1970, 'The Effect of Stress on Cognitive Load Measurement', HUMAN-COMPUTER INTERACTION - INTERACT 2013, PT IV, 14th IFIP TC 13 INTERACT International Conference on Designing for Diversity, Springer Berlin Heidelberg, Cape Town, SOUTH AFRICA, pp. 659-666.
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Das, A, Pal, U, Ballester, MAF & Blumenstein, M 1970, 'A New Method for Sclera Vessel Recognition Using OLBP', Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), Biometric Recognition, Springer International Publishing, Jinan, China, pp. 370-377.
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This paper proposes a new sclera vessel recognition technique. The vessel patterns of sclera are unique for each individual and this can be utilized to identify a person uniquely. In this research we have used a time adaptive active contour-based region growing technique for sclera segmentation. Prior to that, we have made some tonal and illumination correction to get a clearer sclera area without the distributing vessel structure. This is because the presence of complex vessel structures occasionally affects the region-growing process. The sclera vessels are not prominent in the images, so in order to make them clearly visible, a local image enhancement process using a Haar high pass filter is incorporated. To get the total orientation of the vessels, we have used Orientated Local Binary Pattern (OLBP). The OLBP images of each class are used for template matching for classification by calculating the minimum Hamming Distance. We have used the UBIRIS version 1 dataset for the experimentation of our research. The proposed approach has achieved high recognition accuracy employing the above-mentioned dataset. © Springer International Publishing 2013.
Das, A, Pal, U, Blumenstein, M & Ballester, MAF 1970, 'Sclera Recognition - A Survey', 2013 2nd IAPR Asian Conference on Pattern Recognition, 2013 2nd IAPR Asian Conference on Pattern Recognition (ACPR), IEEE, Naha, Japan, pp. 917-921.
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This paper presents a survey on sclera-based biometric recognition. Among the various biometric methods, sclera is one of the novel and promising biometric techniques. The sclera, a white region of connective tissue and blood vessels, surrounds the iris. A survey of the techniques available in the area of sclera biometrics will be of great assistance to researchers, and hence a comprehensive effort is made in this article to discuss the advancements reported in this regard during the past few decades. As a limited number of publications are found in the literature, an attempt is made in this paper to increase awareness of this area so that the topic gains popularity and interest among researchers. In this survey, a brief introduction is given initially about the sclera biometric, which is subsequently followed by background concepts, various pre-processing techniques, feature extraction and finally classification techniques associated with the sclera biometric. Benchmarking databases are very important for any pattern recognition related research, so the databases related with this work is also discussed. Finally, our observations, future scope and existing difficulties, which are unsolved in sclera biometrics, are discussed. We hope that this survey will serve to focus more researcher attention towards the emerging sclera biometric. © 2013 IEEE.
Das, A, Pal, U, Ferrer Ballester, MA & Blumenstein, M 1970, 'Sclera recognition using dense-SIFT', 2013 13th International Conference on Intellient Systems Design and Applications, 2013 13th International Conference on Intelligent Systems Design and Applications (ISDA), IEEE, Bangi, Malaysia, pp. 74-79.
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© 2013 IEEE. In this paper we propose a biometric sclera recognition and validation system. Here the sclera segmentation is performed bya time-adaptive active contour-based region growing technique. The sclera vessels are not prominent so image enhancement is required and hence a bank of 2D decomposition. A Haar wavelet multi-resolution filter is used to enhance the vessels pattern for better accuracy. For feature extraction, Dense Scale Invariant Feature Transform (D-SIFT) is used. D-SIFT patch descriptors of each training image are used to form bag of features by using k-means clustering and a spatial pyramid model, which is used to produce the training model. Support Vector Machines (SVMs) are used for classification. The UBIRIS version 1 dataset is used here for experimentation. Anencouraging Equal Error Rate (EER) of 0.66% is attained in the experiments presented.
De Silva Wijayaratna, K 1970, 'Reliability of the South West Sydney Transport Corridor', Australian Institute of Traffic Planning and Management (AITPM) National Conference, Perth, Western Australia.
Fatahi, B, Le, T & Khabbaz, H 1970, 'Influence Of Insitu Stresses On Deformation And Stability Of Embankments On Deep Clays', Proceedings of the International Conference on Ground Improvement and Ground Control, Ground Improvement And Ground Control: Transport Infrastructure Development and Natural Hazards Mitigation, Research Publishing, Wollongong, Australia, pp. 491-496.
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Time dependent behavior of soft soils under embankments is one of the challenging problems in geotechnical engineering, since soft ground has been utilised for development. This paper presents a numerical study of the influence of the initial stress state on the ground lateral deformation and pore water pressure by revisiting a case study of an embankment constructed on Boston Blue Clay. The insitu stress state is usually determined by the coefficient of lateral earth pressure at rest (K0), but there are various correlations to estimate the value of K0. In this paper, a numerical parametric study is conducted to investigate the effect of K0 on the vertical and horizontal displacements, the excess pore water pressures, and the factor of safety of the embankment. The results show that the value of K0 has notable influences on the predictions of horizontal and vertical displacements, but minor effects on the predicted pore water pressures. The choice of the lateral earth pressure coefficient at rest also has impact on the long term stability of the embankment. Thus, it is emphasised that the initial stress state should be concerned regarding the stability of the embankment for analysing the performance of embankments constructed on deep soft soils.
Fatahi, B, Le, T & Khabbaz, H 1970, 'INFLUENCE OF SOIL CREEP ON STABILITY OF EMBANKMENT ON SOFT SOIL', Ground Improvement and Ground Control, International conference on Ground Improvement and Ground Control, Research Publishing, Wollongong, Australia, pp. 485-490.
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As a result of the scarcity of land for construction, number of projects to construct man-made islands or to expand lands over soft grounds keeps increasing. Consolidation and creep are significant in the soft soil and hence, their long term deformation must be taken into account in engineering design and practice. Soil creep has significant impacts on the stability of the structures constructed on the soft ground. In this paper, a case study of an embankment constructed in stages in north Boston over a thick layer of Boston Blue Clay is numerically investigated in order to consider the effects of the soil creep. The behaviour of the ground is simulated using a finite element program associated with and without soil creep. A parametric study on the soil creep ratio is conducted to evaluate its effects on the predictions of the excess pore water pressure and lateral displacement. It is observed that the increase in the value of creep index causes the increases in both of the horizontal displacements and excess pore water pressures of the ground. In addition, the factor of safety against slope instability decreases with the creep ratio. Thus, the effects of soil creep should be earnestly considered in predicting the ground performance under embankments.
Hagelstein, B, Abolhasan, M, Franklin, D, Safaei, F & IEEE 1970, 'A General Performance Model for MAC Layer Cooperative Retransmission Contention Protocols', 2013 IEEE GLOBAL COMMUNICATIONS CONFERENCE (GLOBECOM), IEEE Global Telecommunications Conference, IEEE, Atlanta, USA, pp. 1584-1589.
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Cooperative retransmission schemes can significantly improve transmission reliability and performance over high loss and time-varying links. However, analytically comparing performance between retransmission strategies is challenging and generally requires simplistic assumptions. This paper presents a general model for the performance of distributed, slot-based contention algorithms for opportunistic decode and forward retransmission algorithms. The model is independent of specific modulation or coding schemes and may be adapted to suit statebased transmission probability models. The model is validated through QualNet simulations.
Heitor, A, Rujikiatkamjorn, C & Indraratna, B 1970, 'Behaviour of a compacted silty sand under constant water content shearing', 18th International Conference on Soil Mechanics and Geotechnical Engineering: Challenges and Innovations in Geotechnics, ICSMGE 2013, pp. 1007-1010.
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The structure derived from compacting the soil at different water contents and energy levels can have a substantial effect on its shear strength. While the shear strength with varying suction can be estimated based on the saturated shear strength parameters and the unsaturated angle of shearing resistance (b), limited studies have explored the variation of shear strength properties with different compaction states. In this paper, the shear strength of a silty sand soil was investigated using a conventional direct shear box under constant water content condition. The tests were conducted on specimens prepared by Proctor compaction with three different normal pressures. The shear strength parameters were obtained and modelled in terms of ultimate states.
Ho, H, Fatahi, B & Khabbaz, H 1970, 'Exact Solution to Predict Excess Pore Pressures and Settlement of Unsaturated Soil Deposit due to Uniform Loading', GEO Montreal 2013, GeoMontreal, Canadian Geotechnical Society, Hilton Bonaventure Montreal Hotel, pp. 1-6.
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This paper explains a simple yet precise analytical solution for the nonlinear governing equations for one-dimensional (1D) consolidation of an unsaturated soil deposit using eigenfunction expansions and Laplace transform techniques. The mathematical development adopts two-way drainage condition for the unsaturated soil, in which the permeable top and base boundaries allow free dissipation of pore-air and pore-water pressures under uniform loading. Eigenfunctions and eigenvalues are parts of the general solution and can be obtained based on the proposed drainage boundary condition. Furthermore, uniformly distributed initial pore pressures can be used to determine the initial generalised Fourier coefficients. Besides, Laplace transform method is adopted to solve the first-order differential equations. Once the equations with transformed domain are obtained, the final solutions, which are proposed to be functions of time (t) and depth (z), can be achieved by taking an inverse Laplace transform. A worked example is provided to present the consolidation characteristics of unsaturated soils based on the proposed solution. Significance of air permeability to water permeability ratio on the excess pore water and air pressure dissipation rates is investigated and discussed.
Hokmabadi, AS, Fatahi, B & Samali, B 1970, 'Seismic response of superstructure on soft soil considering soil-pile-structure interaction', 18th International Conference on Soil Mechanics and Geotechnical Engineering: Challenges and Innovations in Geotechnics, ICSMGE 2013, International Conference on Soil Mechanics and Geotechnical Engineering, Presses des Ponts, Paris, France, pp. 547-550.
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This paper presents results of shaking table tests and three dimensional numerical simulations to investigate the influence of Soil-Pile-Structure Interaction (SPSI) on the seismic response of mid-rise moment resiting buildings supported by end-bearing pile foundations. Three different cases have been considered, namely: (i) fixed-base structure representing the situation excluding the soil-structure interaction; (ii) structure supported by shallow foundation on soft soil; and (iii) structure supported by end-bearing pile foundation in soft soil. Comparison of the numerical predictions and the experimental data shows a good agreement confirming the reliability of the numerical model. Both experimental and numerical results indicate that soil-structure interaction induces significant increase in the lateral deflections and inter-storey drifts of the structures on both shallow and end-bearing pile foundations in comparison to the fixed base structures. This increase in the lateral deformations and in turn inter-storey drifts can change the performance level of the structure during earthquakes which may be safety threatening.
Indraratna, B, Nimbalkar, S, Rujikiatkamjorn, C, Neville, T & Christie, D 1970, 'Performance assessment of synthetic shock mats and grids in the improvement of ballasted tracks', 18th International Conference on Soil Mechanics and Geotechnical Engineering: Challenges and Innovations in Geotechnics, ICSMGE 2013, pp. 1283-1286.
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In Australia, railways offer the most prominent transportation mode in terms of traffic tonnage serving the needs of bulk freight and passenger movement. Ballast is an essential constituent of conventional rail infrastructure governing track stability and performance. However, in recent times, higher traffic induced stresses due to dramatically increased train speeds and heavier axle loads have caused excessive plastic deformations and degradation of ballast. This seriously hampers safety and efficiency of express tracks, for instance, enforcing speed restrictions and effecting more frequent track maintenance. Installing layers of synthetic materials such geogrids and rubber pads (shock mats) in rail tracks can significantly reduce ballast degradation. Field trials were conducted on rail track sections in the towns of Bulli (near Wollongong City) and Singleton (near Newcastle) to measure track deformations associated with cyclic stresses and impact loads. This paper describes the results of large-scale laboratory testing as well as the observations from full-scale instrumented field trials characterising the behaviour of rail ballast improved by shock mats and synthetic grids.
Indraratna, B, Rujikiatkamjorn, C & Balasubramaniam, AS 1970, 'Ground Improvement at the Port of Brisbane, Australia Using Vertical Drains and Vacuum Assisted Preloading', Sound Geotechnical Research to Practice, Geo-Congress 2013, American Society of Civil Engineers.
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Indraratna, B, Rujikiatkamjorn, C, Geng, X & Ameratunga, J 1970, 'Performance and prediction of vacuum consolidation behavior at Port of Brisbane', 18th International Conference on Soil Mechanics and Geotechnical Engineering: Challenges and Innovations in Geotechnics, ICSMGE 2013, pp. 2497-2500.
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due to a projected increase in trade activities at the port of Brisbane, new berths on fisherman islands at the mouth of the Brisbane river will be constructed in the outer area (235ha) close to the existing port facilities via land reclamation. a vacuum assisted surcharge load in conjunction with prefabricated vertical drains was choosen to reduce the required consolidation time. the features of the combined vacuum and surcharge fill system and the construction of the embankment are described in this paper. a comparison of the performance of the vacuum combined surcharge loading system with a standard surcharge fill emphasizes the obvious advantages of vacuum consolidation. field data is presented to show how the embankment performed during construction. an analytical solution for radial consolidation incorporating both time-dependent surcharge loading and vacuum pressure is employed to calculate the settlements and associated excess pore pressures of the soft holocene clay deposits.
Indraratnaa, B, Tennakoon, N, Nimbalkar, S & Rujikiatkamjorn, C 1970, 'Effects Of Fouling On The Stress—Strain—Degradation Behaviour Of Rail Ballast', Proceedings of the 18th Southeast Asian Geotechnical Conference (18SEAGC) & Inaugural AGSSEA Conference (1AGSSEA), 18th Southeast Asian Geotechnical Conference (18SEAGC) & Inaugural AGSSEA Conference (1AGSSEA), Research Publishing Services.
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Jiang, X, Li, Y & Li, J 1970, 'A piezoelectric wafer-stack vibration energy harvester for wireless sensor networks', SENSORS AND SMART STRUCTURES TECHNOLOGIES FOR CIVIL, MECHANICAL, AND AEROSPACE SYSTEMS 2013, Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems, SPIE, San Diego, USA, pp. 1-9.
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Over the past few decades, wireless sensor networks have been widely used in civil structure health monitoring application. Currently, most wireless sensor networks are battery-powered and it is costly and unsustainable for maintenance because of the requirement for frequent battery replacements. As an attempt to address such issue, this paper presents a novel piezoelectric vibrational energy harvester to convert the structural vibration into usable electrical energy for powering wireless sensor networks. Unlike the normal cantilever beam structure, the piezoelectric harvester presented in this paper is based on the wafer-stack configuration which is suitable for applications where large force vibration occurs, and therefore can be embedded in civil structures to convert the force induced by vibration of large structures directly into electrical energy. The longitudinal mode of the piezoelectric wafer-stack was developed firstly to illustrate the force-to-voltage relationship of piezoelectric materials and to find the inter-medium force that will be used to convert vibration energy into electrical energy. Then, two electromechanical models (without and with a rectified circuit), considering both the mechanical and electrical aspects of the harvester, were developed to characterize the harvested electrical power under the external load. Exact closed-form expressions of the electromechanical models have been derived to analyze the maximum harvested power and the optimal resistance. Finally, a shake table experimental testing was conducted to prove the feasibility of the presented piezoelectric-wafer-stack harvester under standard sinusoidal loadings. Test results show that the harvester can generate a maximum 45mW (AC) or 16mW (DC) electrical power for sinusoidal loading with 40mm amplitude and 2Hz frequency, and the harvested electrical power is proportional to the levels of exciting vibrational loading. © 2013 SPIE.
Kim, YS, Zhang, N, Ji, JC, Yuen, WYD & ASME 1970, 'THE EFFECT OF ROLLING SPEED AND FRICTION ON COLD ROLLING MILL STABILITY', INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION - 2012, VOL 12, International Mechanical Engineering Congress & Exposition, ASME, USA, pp. 291-299.
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In order to investigate the validity of a coupled mill vibration model presented in the dynamic rolling formulation, this paper presents the results of dynamic characteristics examining rolling force variations in response to rolling parameters. Under the given steady state rolling condition, the unstable vibrational modes with corresponding frequencies are identified and stability analysis is also performed to demonstrate that the proposed model is highly dependent on the rolling speed and friction coefficient with an assumed negative gradient of friction coefficient. To further find the transient characteristics and the direct influences of the friction coefficient and rolling speed on the mill chatter, the derived equations of motion of the system are solved using Runge- Kutta numerical integration method. Simulations are carried out to reveal the chatter sources, which gives rise to unstable rolling vibrations. Copyright © 2012 by ASME.
Kunwar, R, Pal, U & Blumenstein, M 1970, 'Semi-supervised Online Learning of Handwritten Characters Using a Bayesian Classifier', 2013 2nd IAPR Asian Conference on Pattern Recognition, 2013 2nd IAPR Asian Conference on Pattern Recognition (ACPR), IEEE, Naha, Japan, pp. 717-721.
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This paper addresses the problem of creating a handwritten character recognizer, which makes use of both labelled and unlabelled data to learn continuously over time to make the recognisor adaptable. The proposed method makes learning possible from a continuous inflow of a potentially unlimited amount of data without the requirement for storage. It highlights the use of unlabelled data for better parameter estimation, especially when labelled data is scarce and expensive unlike unlabelled data. We introduce an algorithm for learning from labelled and unlabelled samples based on the combination of novel online ensemble of the Randomized Naive Bayes classifiers and a novel incremental variant of the Expectation Maximization (EM) algorithm. We make use of a weighting factor to modulate the contribution of unlabelled data. An empirical evaluation of the proposed method on Tamil handwritten base character recognition proves efficacy of the proposed method to carry out incremental semi-supervised learning and producing accuracy comparable to state-of-the-art batch learning method. Online handwritten Tamil characters from the IWFHR 2006 competition dataset was used for evaluating the proposed method. © 2013 IEEE.
Laird, J, Geers, DG, Wang, Y & Chou, CT 1970, 'Integrating video cameras for ALINEA on-ramp queue length estimation', 16th International IEEE Conference on Intelligent Transportation Systems (ITSC 2013), 2013 16th International IEEE Conference on Intelligent Transportation Systems - (ITSC 2013), IEEE, The Hague, NETHERLANDS, pp. 1571-1578.
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Le, TM, Van Le, P, Khabbaz, H & Fatahi, B 1970, 'Stability and Deformation of Sheet Pile Walls for Protecting Riverside Structures in the Mekong River Delta', Geo-Congress 2013, Geo-Congress 2013, American Society of Civil Engineers, San Diego, California, pp. 1349-1358.
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Regions of the Mekong River Delta consist of soft soil, which causes significant issues on the stability and deformation of the surrounding structures, especially the riverside structures. Sheet pile walls are considered as one of the effective methods used to support the riverside structures against soil sliding and flooding. This paper presents a precise study on the stability and deformation of sheet pile walls constructed along the riverside areas in the Mekong River Delta. An approach founded on the limit equilibrium method is proposed to solve the equilibrium equations of lateral forces and moments. The proposed approach allows the designed depth of embedment to be determined by the factor of safety. Additionally, it is a simple method to analyze the performance of sheet walls in multi-layered ground conditions. A program code is written to implement the proposed method. In this paper, in order to evaluate the stability and deformation of the walls, the prediction results obtained by the developed method are compared to the results by finite element analysis. Furthermore, the results show that the predicted maximum lateral movement of the wall is in reasonable agreement with the field measurement. © 2013 American Society of Civil Engineers.
Li, J, Li, Y, Li, W & Samali, B 1970, 'Development of adaptive seismic isolators for ultimate seismic protection of civil structures', SENSORS AND SMART STRUCTURES TECHNOLOGIES FOR CIVIL, MECHANICAL, AND AEROSPACE SYSTEMS 2013, Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems, SPIE, San Diego, USA, pp. 1-12.
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Base isolation is the most popular seismic protection technique for civil engineering structures. However, research has revealed that the traditional base isolation system due to its passive nature is vulnerable to two kinds of earthquakes, i.e. the near-fault and far-fault earthquakes. A great deal of effort has been dedicated to improve the performance of the traditional base isolation system for these two types of earthquakes. This paper presents a recent research breakthrough on the development of a novel adaptive seismic isolation system as the quest for ultimate protection for civil structures, utilizing the field-dependent property of the magnetorheological elastomer (MRE). A novel adaptive seismic isolator was developed as the key element to form smart seismic isolation system. The novel isolator contains unique laminated structure of steel and MR elastomer layers, which enable its large-scale civil engineering applications, and a solenoid to provide sufficient and uniform magnetic field for energizing the field-dependent property of MR elastomers. With the controllable shear modulus/damping of the MR elastomer, the developed adaptive seismic isolator possesses a controllable lateral stiffness while maintaining adequate vertical loading capacity. In this paper, a comprehensive review on the development of the adaptive seismic isolator is present including designs, analysis and testing of two prototypical adaptive seismic isolators utilizing two different MRE materials. Experimental results show that the first prototypical MRE seismic isolator can provide stiffness increase up to 37.49%, while the second prototypical MRE seismic isolator provides amazing increase of lateral stiffness up to 1630%. Such range of increase of the controllable stiffness of the seismic isolator makes it highly practical for developing new adaptive base isolation system utilizing either semi-active or smart passive controls. © 2013 SPIE.
Lloret-Cabot, M & Sheng, D 1970, 'Coupling between mechanical and water retention behaviour in unsaturated soils', Computational Geomechanics, COMGEO III - Proceedings of the 3nd International Symposium on Computational Geomechanics, pp. 32-41.
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The importance of incorporating appropriate coupling mechanisms between the mechanical and the water retention behaviour in a constitutive model of unsaturated soils has been demonstrated in a number of studies (e.g. Wheeler et al., 2003; Sheng & Zhou, 2011; Zhou et al., 2012). For example, the experimental results of Romero (1999) on Boom clay show that the water retention behaviour exhibits a significant dependence on the void ratio, or the data from Sharma (1998) demonstrates that the occurrence of different degrees of saturation at the same value of suction, as a consequence of hydraulic hysteresis, can influence the mechanical response of the soil. This paper analyses how the experimentally observed coupled behaviour in unsaturated soils is incorporated in two well-established constitutive models. A brief introduction of the considered models is presented first, followed by a description on how these models account for the coupling between water retention and mechanical behaviour. In order to investigate further the proposed relationships for the couplings, a number of fictitious stress paths are simulated to analyze the volumetric and water retention predictions given by each of the models used.
Malik, MI, Liwicki, M, Alewijnse, L, Ohyama, W, Blumenstein, M & Found, B 1970, 'ICDAR 2013 Competitions on Signature Verification and Writer Identification for On- and Offline Skilled Forgeries (SigWiComp 2013)', 2013 12th International Conference on Document Analysis and Recognition, 2013 12th International Conference on Document Analysis and Recognition (ICDAR), IEEE, Washington, DC, USA, pp. 1477-1483.
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This paper presents the results of the ICDAR2013 competitions on signature verification and writer identification for on- and offline skilled forgeries jointly organized by PR researchers and Forensic Handwriting Examiners (FHEs). The aim is to bridge the gap between recent technological developments and forensic casework. Two modalities (signatures, and handwritten text) are considered where training and evaluation data (in Dutch and Japanese) were collected and provided by FHEs and PR-researchers. Four tasks were defined where the systems had to perform Dutch offline signature verification, Japanese offline signature verification, Japanese online signature verification, and Dutch writer identification. The participants of the signatures modality were motivated to report their results in Likelihood Ratios (LR). This has made the systems even more interesting for application in forensic casework. For evaluation of signatures modality, we used both the traditional Equal Error Rate (EER) and forensically substantial Cost of Log Likelihood Ratios (Cllr). The system having the smallest value of the Minimum Cost of Log Likelihood Ratio (Cllrmin) is declared winner. For evaluation of the handwritten text modality, we used the precision and accuracy measures and winners are announced on the basis of best F-measure value. © 2013 IEEE.
Mandal, R, Roy, PP, Pal, U & Blumenstein, M 1970, 'Signature segmentation and recognition from scanned documents', 2013 13th International Conference on Intellient Systems Design and Applications, 2013 13th International Conference on Intelligent Systems Design and Applications (ISDA), IEEE, Bangi, Malaysia, pp. 80-85.
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© 2013 IEEE. Signature as a query is important for content-based document image retrieval from a scanned document repository. This paper presents a two-stage approach towards automatic signature segmentation and recognition from scanned document images. In the first stage, signature blocks are segmented from the document using word-wise component extraction and classification. Gradient based features are extracted from each component at the word level to perform the classification task. In the 2nd stage, SIFT (Scale-Invariant Feature Transform) descriptors and Spatial Pyramid Matching (SPM)-based approaches are used for signature recognition. Support Vector Machines (SVMs) are employed as the classifier for both levels in this experiment. The experiments are performed on the publicly available 'Tobacco-800' and GPDS [1] datasets and the results obtained from the experiments are promising.
McFarlane, DA, Buchroithner, M, Lundberg, J, Petters, C, Roberts, W & Van Rentergen, G 1970, 'Integrated three-dimensional laser scanning and autonomous drone surface-photogrammetry at Gomantong Caves, Sabah, Malaysia', Proceedings of the 16th International Congress of Speleology, Brno, pp. 317-319.
Mollaee, S, Pirasteh, S, Ramli, MF & Rizvi, SMA 1970, 'Identifying Effecting Factors and Landslide Mapping of Cameron Highland Malaysia', 2013 Fifth International Conference on Geo-Information Technologies for Natural Disaster Management, 2013 Fifth International Conference on Geo-Information Technologies for Natural Disaster Management (GiT4NDM), IEEE, pp. 73-83.
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Movassaghi, S, Abolhasan, M & Smith, D 1970, 'Interference Mitigation in WBANS: Challenges and Existing Solutions', Workshop on Advances in Real-time Information Networks, Samaneh Movassaghi, University of Technology, Sydney, Australia, pp. 1-4.
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Wireless Body Area Networks (WBANs) are an exciting new networking technology developed in the recent years with advancements in wireless communication, integrated circuits and Micro-Electro- Mechanical Systems (MEMs). They consist of a number of sensor nodes that are placed in or around the human body. However, their practical deployment requires addressing numerous challenges. WBANs face many stringent requirements in power, bandwidth, and network lifetime which need to be taken into serious consideration in the design of different protocols. In this paper, we investigate the importance of interference mitigation amongst coexisting Wireless Body Area Networks (WBANs). Since, a WBAN is most likely to encounter other WBANs, inter-WBAN interference and scheduling is of utmost importance.
Movassaghi, S, Shirvanimoghaddam, M, Abolhasan, M & IEEE 1970, 'A Cooperative Network Coding Approach to Reliable Wireless Body Area Networks with Demodulate-and-Forward', 2013 9TH INTERNATIONAL WIRELESS COMMUNICATIONS AND MOBILE COMPUTING CONFERENCE (IWCMC), International Wireless Communications and Mobile Computing Conference, IEEE, Italy, pp. 394-399.
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In this paper, a novel cooperative transmission scheme via network coding has been proposed for Wireless Body Area Networks (WBANs) to enhance reliability and throughput. In the proposed scheme, namely Random XOR Network Coding (RXNC), each relay demodulates the received signal from each sensor node and then selects d different coded symbols amongst them and XORs them to generate a network coded symbol. We have found the optimum value of d through an analytical approach by minimizing the probability that an XOR network coded symbol is incorrectly generated. Simulation results show that the proposed RXNC scheme outperforms the no-cooperation and conventional bitwise network coding schemes in all channel signal to noise ratios (SNRs) from 0 dB to 18 dB.
Movassaghi, S, Shirvanimoghaddam, M, Abolhasan, M & Smith, D 1970, 'An energy efficient network coding approach for Wireless Body Area Networks', 38th Annual IEEE Conference on Local Computer Networks, 38th Annual IEEE Conference on Local Computer Networks (LCN 2013), IEEE, Sydney, NSW, Australia, pp. 468-475.
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In this paper, we propose a practical network coding approach for wireless body are networks (WBANs) using decode-and-forward relays. In this scheme, namely decode and forward-network coding (DF-NC), each relay linearly combines different messages from different sources to generate one message, and then transmits that message to the destination. Each relay node in DF-NC requires only one transmission time slot to forward its message. Thus, in this approach, energy usage at each relay is minimized compared to existing cooperative schemes without network coding, which require Ns time slots per relay for relay transmissions; where Ns is the number of source nodes. Simulation results show that the proposed DF-NC scheme can achieve near optimal outage probability while minimizing the number of transmissions per node, maximizing the energy efficiency of WBANs, and minimizing the delay
Mukunthan, A, Cooper, C, Safaei, F, Franklin, D, Abolhasan, M, Ros, M & IEEE 1970, 'Experimental Validation of the CORNER Urban Propagation Model based on Signal Power Measurements in a Vehicular Environment', 2013 IEEE WIRELESS COMMUNICATIONS AND NETWORKING CONFERENCE (WCNC), IEEE Wireless Communications and Networking Conference, IEEE, Shanghai, China, pp. 2626-2631.
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CORNER is an urban propagation model which simulates the presence of buildings in city scenarios and models radio propagation as a series of reflections and diffractions around buildings. CORNER was validated in the original publication with a series of packet-delivery-ratio measurements. However, the accuracy of these measurements is limited by interference from nearby networks. This paper independently evaluates the CORNER model using signal strength measurements across three separate sites in Sydney and Wollongong. The measurements are analysed and compared with the predicted analytical estimates. The fading model is also analysed with direct measurements. A new CORNER link classification algorithm is also proposed in this paper
Nguyen, L, Fatahi, B & Khabbaz, H 1970, 'Predicting behaviour of cemented clay considering strength reduction due to high confining pressure', GeoMontreal 2013, GeoMontreal, Canadian Geotechnical Society, Montreal, Canada, pp. 1-6.
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A predictive constitutive model referred to as Cemented Cam Clay (CCC) model developed by the authors is presented in this paper to precisely predict the behaviour of cemented clay capturing the effect of cementation degradation during loading. When the confining pressure increases, the effect of cementation gradually diminishes due to the breakdown of cementation bonds as observed in laboratory experiments. The proposed model includes a non-associated plastic potential function and elasto-plastic stress-strain relationship inspired by the framework of the critical state concept. The main feature of the proposed model is the formulation of the failure envelope which describes the beneficial effect of cementation at low pressure range. As the confining pressure continues to increase, it gradually merges with the critical state line indicating a degradation of cement bonding. The proposed model is validated through comparison of the model predictions with the results of an array of triaxial tests conducted on Ariake cemented clay.
Nguyen, V, Fatahi, B & Khabbaz, H 1970, 'Three dimensional numerical simulation to predict performance of laterally loaded piles on clay-sand layered slope', GeoMontreal2013, GeoMontreal, GeoMontreal2013, Montreal, Quebec, pp. 1-6.
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Predicting the deformation of the laterally loaded piles constructed on a slope is one of the challenging issues in foundation engineering. Numerical modelling is an efficient method to investigate the effects of the distance from the pile centreline to the slope crest on the performance of laterally loaded piles considering the shear plastic deformations of the ground. In this paper, finite element software, ABAQUS, has been employed to simulate the performance of some piles subjected to lateral loads in the sloping ground including sand and clay layers. Appropriate subroutines have been adopted to simulate the soil-pile interface, capable of incorporating the gapping and sliding in the soil-pile interfaces for both sand and clay layers. The numerical results are used to predict the lateral load-deformation of piles for various cases and validated through comparison with an array of full scale field measurements.
Oberst, S & Lai, JCS 1970, 'The role of pad-mode instabilities in disc brake squeal', 20th International Congress on Sound and Vibration 2013, ICSV 2013, International Congress on Sound and Vibration, Bangkok, Thailand, pp. 2861-2868.
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Automotive disc brake squeal remains an economically significant and technically challenging problem to solve, owing to customer complaints' associated warranty costs and the many interacting parameters. While industrial practice aims at identifying unstable vibration modes using complex eigenvalue analysis, in this paper, we show how to identify pad-mode instabilities using vibration forced response analysis complemented by acoustic radiation calculations for simplified brake systems in the form of a pad-on-plate model. Our recent results indicate that pad-mode instabilities might trigger so-called instantaneous mode squeal without the necessity of mode coupling. Pad-mode instabilities, which complex eigenvalue analysis fails to detect, are revealed by the dissipated energy spectrum at frequencies where the dissipated energy is negative (i.e. providing energy instead of dissipating energy). Pad-modes seem to radiate locally higher sound pressure depending on the phase shift between the structural vibration and the sound pressure while exciting the underlying plate's or disc's modes. Pad-mode instabilities are shown to be one mechanism of brake squeal. In order to identify pad-mode instabilities, it is beneficial to perform a full range of vibration analysis which includes complex eigenvalue value analysis, forced response and dissipated energy spectra as well as acoustic radiation calculations for a range of different parameters such as friction coefficient, operating pressure, temperature and contact conditions.
Oberst, SM & Lai, J 1970, 'The role of pad-modes and nonlinearity in instantaneous mode squeal', Proceedings of Meetings on Acoustics, ICA 2013 Montreal, ASA.
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Disc brake squeal is a major source of customer dissatisfaction and related warranty costs for automobile manufacturers. Although mode coupling is recognised as a mechanism often found in squealing brakes, recent research results show that friction induced pad-mode instabilities could be the cause of instantaneous mode squeal reported in the literature. In this paper, the nonlinear characteristics of instantaneous mode squeal initiated by pad-mode instabilities are studied by analysing phase space plots of vibrations and sound pressure for a numerical model of a pad-on-plate system as the friction coefficient increases. Results show tat as the friction coefficient increases from 0.05 to 0.65, attractors of vibration in the phase space transits from limit cycle to quasi-periodic, showing signs of approaching chaotic behaviour. It is shown here that the correlation of the sound pressure behaviour in the phase-space with structural vibration is crucial to understanding the role of pad modes and nonlinearity in instantaneous mode squeal. © 2013 Acoustical Society of America.
Okumura, U, Qi, YJ, Long, Y & Zhang, TH 1970, 'Research on the Roller Intelligent Detection System Based on LabVIEW', Applied Mechanics and Materials, 2nd International Conference on Civil Engineering, Architecture and Sustainable Infrastructure (ICCEASI 2013), Trans Tech Publications, Ltd., Zhengzhou, PEOPLES R CHINA, pp. 1084-1088.
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Based on the platform of LabVIEW, a set of roller intelligent detecting system is developed. With this system, it is easy to realize functions of fast nondestructive testing of subgrade compaction degree, roller speed, rollers compaction trajectory, compaction times, GPS real-time positioning as well as saving and printing report forms. Compared with traditional detection methods, this detecting system can test and control on-site compaction quality much more easily, in order to speed up the construction progress, improve the quality of subgrade compaction, control and manage compaction work better.
PAL, S, ALAEI, A, PAL, U & BLUMENSTEIN, M 1970, 'SVM AND NN BASED OFFLINE SIGNATURE VERIFICATION', International Journal of Computational Intelligence and Applications, World Scientific Pub Co Pte Lt, pp. 1340004-1340004.
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Among all of the biometric authentication systems, handwritten signatures are considered as the most legally and socially accepted attributes for personal verification. The objective of this paper is to present an empirical contribution toward the understanding of a threshold-based signature verification technique involving off-line Bangla (Bengali) signatures. Experiments on signature verification concerning non-English signatures are an important consideration in the signature verification area. Only very few research works employing signatures of Indian script have been considered in the field of non-English based signature verification. To fill this gap, a threshold-based scheme for the verification of off-line Bangla signatures is proposed. Some techniques such as under-sampled bitmap, intersection/end point and directional chain code are employed for feature extraction. The thresholds are computed based on the similarity measures obtained employing the nearest neighbor classifier. The SVM classifier has also been considered for mainly comparative experimental result generation. Furthermore, a Bangla signature database, which consists of 2400 (100 × 24) genuine signatures and 3000 (100 × 30) forgeries, has been created and is employed for experimentation. An average error rate (AER) of 12.33% was obtained as the best verification result using directional chain code features in this research work. As a comparative study, a different dataset (GPDS-160) has also been considered.
Pal, S, Pal, U & Blumenstein, M 1970, 'A Two-Stage Approach for English and Hindi Off-line Signature Verification', Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), International Conference on Image Analysis and Processing, Springer Berlin Heidelberg, Naples, Italy, pp. 140-148.
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The purpose of this paper is to present an empirical contribution towards the understanding of multi-script off-line signature identification and verification using a novel method involving off-line Hindi (Devnagari) and English signatures. The main aim of this approach is to demonstrate the significant advantage of the use of signature script identification in a multi-script signature verification environment. In the 1 st stage of the proposed signature verification technique a script identification technique is employed to know whether a signature is written in Hindi or English. In the second stage, a verification approach was explored separately for English signatures and Hindi signatures based on the script identification result. Different features like gradient feature, water reservoir feature, loop feature, aspect ratio etc. were employed, and Support Vector Machines (SVMs) were considered in our scheme. To get the comparative idea, multi-script signature verification results on the joint Hindi and English dataset without using any script identification technique is also computed. From the experiment results it is noted that we are able to reduce average error rate 4.81% more when script identification method is employed. © 2013 Springer-Verlag.
Pal, S, Pal, U & Blumenstein, M 1970, 'Hindi and English Off-line Signature Identification and Verification', Advances in Intelligent Systems and Computing, International Conference on Advances in Computing, Springer India, Bengaluru, Karnataka, India, pp. 905-910.
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Biometric systems play a significant role in the field of information security as they are extremely required for user authentication. Signature identification and verification have a great importance for authentication intention. The purpose of this paper is to present an empirical contribution towards the understanding of multi-script (Hindi and English) signature verification. This system will identify whether a claimed signature belongs to the group of English signatures or Hindi signatures from a combined Hindi and English signature datasets and then it will verify signatures using these two resultant signature datasets (Hindi script signature and English script signatures) separately. The modified gradient feature and SVM classifier were employed for identification and verification purposes. To the best of authors' knowledge, the multi-script signature identification and verification has never been used for the task of signature verification and this is the first report of using Hindi and English signatures in this area. Two different results for identification and verification are calculated and analysed. The accuracy of 98.05% is obtained for the identification of signature script using 2160 (1080 Hindi + 1080 English) samples for training and 1080 (540 Hindi + 540 English) samples for testing. The resultant data sets obtained in script identification of signatures were used for verification purpose. The FRR, FAR for Hindi and English was obtained 8.0%, 4.0% and 12.0%, 10.0% respectively. © 2013 Springer.
Pal, S, Pal, U & Blumenstein, M 1970, 'Multi-script off-line Signature verification: A two stage approach', CEUR Workshop Proceedings, International Workshop on Automated Forensic Handwriting Analysis, CEUR, Washington DC, USA, pp. 31-35.
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Signature identification and verification are of great importance in authentication systems. The purpose of this paper is to introduce an experimental contribution in the direction of multi-script off-line signature identification and verification using a novel technique involving off-line English, Hindi (Devnagari) and Bangla (Bengali) signatures. In the first evaluation stage of the proposed signature verification technique, the performance of a multi-script off-line signature verification system, considering a joint dataset of English, Hindi and Bangla signatures, was investigated. In the second stage of experimentation, multi-script signatures were identified based on the script type, and subsequently the verification task was explored separately for English, Hindi and Bangla signatures based on the identified script result. The gradient and chain code features were employed, and Support Vector Machines (SVMs) along with the Modified Quadratic Discriminate Function (MQDF) were considered in this scheme. From the experimental results achieved, it is noted that the verification accuracy obtained in the second stage of experiments (where a signature script identification method was introduced) is better than the verification accuracy produced following the first stage of experiments. Experimental results indicated that an average error rate of 20.80% and 16.40% were obtained for two different types of verification experiments.
Parsa-Pajouh, A, Fatahi, H & Khabbaz, B 1970, 'Numerical analysis to quantify the influence of smear zone characteristics on preloading design in soft clay', 18th International Conference on Soil Mechanics and Geotechnical Engineering: Challenges and Innovations in Geotechnics, ICSMGE 2013, International Conference on Soil Mechanics and Geotechnical Engineering, Presses des Ponts, Paris, France, pp. 2573-2576.
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In this paper, the effects of uncertainties of smear zone characteristics induced by installation of prefabricated vertical drains on the preloading design are numerically investigated. FLAC 2D finite difference software with additional developed subroutines has been employed to conduct the numerical simulations. The finite difference analyses have been verified using a case study. Furthermore, a comprehensive parametric study is conducted to investigate the influence of smear zone permeability and extent on the model predictions. Results of this study indicate that the assumptive properties for smear zone characteristics may result in inaccurate predictions of ground deformations and pore water pressures. This may lead to early removal of the surcharge in the construction process causing excessive post construction settlement. It is recommended to practising engineers to use results of trial preloading to back calculate the required smear zone characteristics in the early stages of embankment construction to optimize the design.
Perrin, R, Hamdan, S, Halkon, B & Swallowe, GM 1970, 'Studies with a small gamelan gong', Proceedings of the Institute of Acoustics, pp. 337-344.
Pineda, JA, Kelly, R, Bates, L, Sheng, D & Sloan, S 1970, 'Effects of Pore Fluid Salinity on the Shear Strength of a Soft Clay', Poromechanics V, Fifth Biot Conference on Poromechanics, American Society of Civil Engineers, pp. 1460-1469.
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The paper presents the results from a preliminary study focused on the influence of pore fluid salinity on the shear strength of a soft clay from New South Wales (Australia). Direct shear tests (DST) were carried out on natural specimens using pore fluids with different salt concentrations. Electrical conductivity measurements were performed on the squeezed pore water after shearing to quantify changes in salinity of the soil pore water. Strength parameters showed a clear dependency of the pore fluid. Changes in c' and φ appear to be controlled by two factors: (i) initial salinity, and (ii) extent of the concentration gradient. Results from mercury intrusion porosimetry tests demonstrated the influence of changes in pore water salinity on the evolution of the dominant pore size. It was in agreement with macroscopic observations. Implications for further laboratory testing are highlighted in the paper. © 2013 American Society of Civil Engineers.
Pradhan, B & Nampak, H 1970, 'Application of fuzzy operators to groundwater potential mapping using remote sensing data and gis', 34th Asian Conference on Remote Sensing 2013, ACRS 2013, pp. 3213-3221.
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The main aim of this research is to investigate potential application of a data driven fuzzy logic method for spatial prediction of groundwater productivity potential mapping in the Langat basin area, Selangor, Malaysia using geographic information system (GIS). The spatial relationships between groundwater yield measurements and spatial factors relevant to productivity of yield were analyzed. Yield measurements were collected from well locations and high yield values were input to a spatial database and randomized in a ratio of 70:30 for training and validation of the model, respectively. Based on the groundwater occurrence and the spatial factors relevant yield measurements, fuzzy membership values for these evidences were estimated using frequency ratio approach. Then the fuzzy algebraic operators were applied to the fuzzy membership values for groundwater productivity potential mapping. Finally, the produced map was validated by comparing with existing well locations for prediction accuracy computation. Copyright © (2013) by the Asian Association on Remote Sensing.
Rafiei, A, Maali, Y, Abolhasan, M, Franklin, D, Safaei, F, Smith, S & IEEE 1970, 'A Tuned Fuzzy Logic Relocation Model in WSNs Using Particle Swarm Optimization', 2013 IEEE 78TH VEHICULAR TECHNOLOGY CONFERENCE (VTC FALL), IEEE Vehicular Technology Conference, IEEE-VTS, Las Vegas, USA, pp. 1-5.
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In harsh and hostile environments, swift relocation of currently deployed nodes in the absence of centralized paradigm is a challenging issue in WSNs. Reducing the burden of centralized relocation paradigms by the distributed movement models comes at the price of unpleasant oscillations and excessive movements due to nodes' local and limited interactions. If the nodes' careless movements in the distributed relocation models are not properly addressed, their power will be exhausted. Therefore, in order to exert proper amount of virtual radial/angular push/pull forces among the nodes, a fuzzy logic relocation model is proposed and by considering linear combination of the presented performance metric(s)(i.e. coverage, uniformity, and average movement), its parameters are locally and globally tuned by particle swarm optimization(PSO). In order to tune fuzzy parameters locally and globally, PSO benefits respectively from nodes' neighbours within different ranges and all the given deployed area. Performance of locally and globally tuned fuzzy relocation models is compared with one another in addition to the distributed self-spreading algorithm (DSSA). It is shown that by applying PSO to the linear combinations of desired metric(s) to obtain tuned fuzzy parameters, the relocation model outperforms and/or is comparable to DSSA in one or more performance metric(s). Copyright © 2013 by the Institute of Electrical and Electronic Engineers, Inc.
Rafiei, A, Maali, Y, Abolhasan, M, Franklin, DR & Smith, S 1970, 'An iteratively tuned fuzzy logic movement model in WSN using particle swarm optimization.', ICSPCS, International Conference on Signal Processing and Communication Systems, IEEE, Carrara, VIC, Australia, pp. 1-7.
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In contrast to adding new nodes, relocation of deployed nodes in mobile wireless sensor networks seems to be an effective solution to cope with undesirable, unpredictable and uncontrolled network topology changes due to nodes' drift and failure. At the price of less global control, there is a trend in recent years towards giving nodes more autonomy and devising localized relocation algorithms to address challenges of network topology control in harsh and hostile environments in the absence of centralized control. Inspired by laws of nature, a large variety of distributed node relocation algorithms have been designed to alleviate undesirable oscillations caused by local interactions and uncertainties among autonomous nodes as they reach their desired formations. Force-based distributed relocation algorithms governed by virtual push-pull forces among autonomous nodes are among such aforesaid algorithms. Adapting fuzzy logic model in exerting proper amount of forces to reduce node movement oscillation seems to be promising as its conforms well with uncertainties and interactions of autonomous nodes. However, parameters of fuzzy logic relocation model should be tuned so to enable nodes to exert proper amount of forces among their in-range neighbours. In this paper, by using particle swarm optimization, parameters of fuzzy relocation model are obtained based on the desired combinations of performance metrics within nodes' range in each movement iteration. The result shows that our model either outperforms or matches DSSA movement model. © 2013 IEEE.
Sharma, N, Chanda, S, Pal, U & Blumenstein, M 1970, 'Word-Wise Script Identification from Video Frames', 2013 12th International Conference on Document Analysis and Recognition, 2013 12th International Conference on Document Analysis and Recognition (ICDAR), IEEE, Washington, DC, USA, pp. 867-871.
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Script identification is an essential step for the efficient use of the appropriate OCR in multilingual document images. There are various techniques available for script identification from printed and handwritten document images, but script identification from video frames has not been explored much. This paper presents a study of some pre-processing techniques and features for word-wise script identification from video frames. Traditional features, namely Zernike moments, Gabor and gradient, have performed well for handwritten and printed documents having simple backgrounds and adequate resolution for OCR. Video frames are mostly coloured and suffer from low resolution, blur, background noise, to mention a few. In this paper, an attempt has been made to explore whether the traditional script identification techniques can be useful in video frames. Three feature extraction techniques, namely Zernike moments, Gabor and gradient features, and SVM classifiers were considered for analyzing three popular scripts, namely English, Bengali and Hindi. Some pre-processing techniques such as super resolution and skeletonization of the original word images were used in order to overcome the inherent problems with video. Experiments show that the super resolution technique with gradient features has performed well, and an accuracy of 87.5% was achieved when testing on 896 words from three different scripts. The study also reveals that the use of proper pre-processing approaches can be helpful in applying traditional script identification techniques to video frames. © 2013 IEEE.
Sharma, N, Shivakumara, P, Pal, U, Blumenstein, M & Tan, CL 1970, 'A New Method for Character Segmentation from Multi-oriented Video Words', 2013 12th International Conference on Document Analysis and Recognition, 2013 12th International Conference on Document Analysis and Recognition (ICDAR), IEEE, USA, pp. 413-417.
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This paper presents a two-stage method for multi-oriented video character segmentation. Words segmented from video text lines are considered for character segmentation in the present work. Words can contain isolated or non-touching characters, as well as touching characters. Therefore, the character segmentation problem can be viewed as a two stage problem. In the first stage, text cluster is identified and isolated (non-touching) characters are segmented. The orientation of each word is computed and the segmentation paths are found in the direction perpendicular to the orientation. Candidate segmentation points computed using the top distance profile are used to find the segmentation path between the characters considering the background cluster. In the second stage, the segmentation results are verified and a check is performed to ascertain whether the word component contains touching characters or not. The average width of the components is used to find the touching character components. For segmentation of the touching characters, segmentation points are then found using average stroke width information, along with the top and bottom distance profiles. The proposed method was tested on a large dataset and was evaluated in terms of precision, recall and f-measure. A comparative study with existing methods reveals the superiority of the proposed method. © 2013 IEEE.
Shashikant, V, Shariff, ARM, Nordin, L & Pradhan, B 1970, 'Above ground biomass estimation of oil palm tree using PALSAR', 34th Asian Conference on Remote Sensing 2013, ACRS 2013, pp. 2870-2873.
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Quantification of Above Ground Biomass (AGB) across oil palm plantation is essential for wide range of modern-day research and management demands. Information on the spatial distribution of Oil Palm Plantation AGB is therefore important for the Oil Palm industry. In this study, the oil palm plantation in Perak, Malaysia was accessed to obtain the AGB information. The lack of information on biomass due to the uncertainties and cost has limited its availability over the years. This research investigates the determination of AGB of oil palm plantation. Phased Array type L-band Synthetic Aperture Radar (PALSAR) sensor is an added advantage to overcome the cloud problem to analyze the biomass of the oil palm plantation, particularly in cloud covered tropical regions. Ground data of oil palm biomass which covers palms of ages 6,8,10 and 12 years old are compared to the estimation of AGB by PALSAR for all the polarizations. PALSAR images were applied various filters and compared among the four window sizes of 3×3, 5×5, 7×7,and 9×9. The filters used in this study are Gaussian low, Gaussian high, Laplacian and Median filter that was applied in VV polarized image. Speckle suppression index was applied to allow checking of filters' efficiency and thus selection of model building. The resulting model constructed from this study showed a R2 regression of 0.90 with the VV polarization between the field data results and filtered PALSAR data of biomass. Copyright © (2013) by the Asian Association on Remote Sensing.
Sheng, D & Zhou, A 1970, 'Unsaturated soil mechanics: Pitfalls in fundamental principles and engineering relevance', 5th China-Japan Geotechnical Symposium, pp. 30-48.
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The last two to three decades have seen significant advances in the mechanics of unsaturated soils. It is now widely recognized that the fundamental principles in soil mechanics should cover both saturated and unsaturated soils. Nevertheless, there is still a great deal of uncertainties amongst the geotechnical community about how well-established soil mechanics principles for saturated soils can be extended to unsaturated soils. There is sometimes even uncertainty about the necessity of such extension in engineering practice. This paper discusses some common pitfalls related to the fundamental principles that govern the volume change, shear strength and hydro-mechanical behaviour of unsaturated soils. It also discusses the relevance of these principles in engineering practice, in attempt to answer some of the critical questions that are often raised in the geotechnical community.
Tabatabaiefar, HR, Fatahi, B & Samali, B 1970, 'Inelastic lateral seismic response of building frames under influence of bedrock depth variations incorporating soil-structure interaction', From Materials to Structures: Advancement Through Innovation - Proceedings of the 22nd Australasian Conference on the Mechanics of Structures and Materials, ACMSM 2012, Australasian Conference on the Mechanics of Structures and Materials, CRC press/Balkema, Sydney, Australia, pp. 587-592.
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In this study, a fifteen storey moment resisting building frame is selected in conjunction with a soft clayey soil, representing soil class Ee, according to Australian Standards. Different bedrock depths including 10 m, 20 m, and 30m are employed in the numerical modelling using finite difference software FLAC 2D. The above mentioned frame has been analysed under two different boundary conditions: (i) fixed-base (no soilstructure interaction), and (ii) flexible-base (considering soil-structure interaction). Inelastic dynamic analyses under influence of different earthquake records for three mentioned bedrock depths are conducted, and the results in terms of inelastic lateral deflections and inter-storey drifts for the above mentioned boundary conditions are compared and discussed. The results indicate that the bedrock depth variations play a significant role in inelastic lateral seismic response of the building frame under the influence of soil-structure interaction. As the bedrock depth increases, lateral deflections and inter-storey drifts of the structures increase. The mentioned effects can change the performance level of the structures from life safe to near collapse or total collapse. © 2013 Taylor & Francis Group.
Udeshi, A, Halkon, B & Coupland, J 1970, 'An Alternative Technique for Investigating Fluid flow Around the Hand During Front Crawl', Procedia Engineering, 6th Asia-Pacific Congress on Sports Technology (APCST), Elsevier BV, Hong Kong, PEOPLES R CHINA, pp. 176-181.
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This paper presents the novel application of a technique for measuring flow around the hand during a simulated swim stroke with a view to enable a better understanding of propulsion generation in swimming. The technique relies on the instantaneous, non-intrusive, volumetric measurement of 3D velocity fields using a commercially available optical measurement system. A hand and forearm model was towed through a water tank to replicate the pull phase with fluid flow data being captured at regular intervals in a fixed volume through which the model moved. The measurement system included a single body, three-sensor probe for capturing pairs of images which were then processed to determine particle velocities and to characterise the flow. The results were used to investigate changes in mean velocity for six experimental cases based on three different angles of attack and two towing speeds. The results showed that the V3V system could be used to capture velocity data around the hand and for a 45° increase in angle of attack, the velocity magnitude of the flow reduced by half, indicating the presence of lift forces. © 2013 The Authors.
ul Huque, MTI, Munasinghe, KS, Abolhasan, M & Jamalipour, A 1970, 'EAR-BAN: Energy efficient adaptive routing in Wireless Body Area Networks', 2013, 7th International Conference on Signal Processing and Communication Systems (ICSPCS), 2013 7th International Conference on Signal Processing and Communication Systems (ICSPCS), IEEE, Gold Coast, Australia, pp. 1-10.
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Wireless Body Area Network (WBAN), a neoteric intelligent monitoring system, is envisaged to unleash a wave of personalized, advanced and integrated applications in the field of medical, fitness, sports, entertainment, military and consumer electronics. In WBAN, network longevity is a major challenge due to the limitation in the availability of energy supply and routing protocol plays a key role towards making such networks energy efficient. In this paper, we propose an energy efficient cluster based routing protocol for WBANs, named as energy efficient adaptive routing in wireless body area network (EAR-BAN). Although EAR-BAN is a cluster based routing protocol, it also combines the benefits of direct and multi hop transmission methods, depending on the energy level and spatial information of body nodes, to formalize an energy efficient, adaptive and opportunistic routing. Moreover, its centralized operation reduces the computational burden of body nodes.
ul Huque, MTI, Munasinghe, KS, Abolhasan, M & Jamalipour, A 1970, 'SEA-BAN: Semi-autonomous adaptive routing in wireless body area networks', 2013, 7th International Conference on Signal Processing and Communication Systems (ICSPCS), 2013 7th International Conference on Signal Processing and Communication Systems (ICSPCS), IEEE, Australia, pp. 1-7.
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Wireless Body Area Network (WBAN), an intelligent health monitoring system, is introduced advanced and integrated applications in the field of medical, fitness, sports, entertainment, military and consumer electronics. In WBAN, due to the limitation in the availability of energy supply, network longevity is a major challenge. Since 80% of total energy is consumed only because of communication purpose in WBAN, routing protocols play a key role towards making such networks energy efficient. In this paper, we propose an energy efficient cluster-based routing protocol for WBANs, named as semiautonomous adaptive routing in wireless body area network (SEA-BAN). SEA-BAN distributes the energy dissipation evenly among the body nodes and enhances the network lifetime. It is not simply a cluster-based routing protocol; it also combines the benefits of direct transmission and multi-hop transmission methods, depending on the energy level and spatial information of the body nodes, to formalize an adaptive routing. Moreover, its centralized operation reduces the computational burden of body nodes. The comparative analysis of our simulation results show that SEA-BAN enhances the network lifetime by more than 2 times when compared to the multi-hop transmission model and about 8.5 times than the direct transmission model.
Velani, N, Harland, AR & Halkon, BJ 1970, 'The development of a test methodology for the determination of cricket batting helmet performance when subjected to ballistic impacts', 2013 IRCOBI Conference Proceedings - International Research Council on the Biomechanics of Injury, pp. 424-430.
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The study presented in this paper was conducted in support of the development of a proposed revision to a cricket helmet certification test standard. Helmets were impacted between the peak and faceguard by 'projecting' balls at them at velocities up to 80 mph. The velocity at which the balls penetrated between the peak and the faceguard (or grille) for the various permissible peak-grille gap settings for each helmet was recorded. The study progressed to compare these penetration velocities against the equivalent found when 'game-aligned' alternate (drop) test methodologies were used. The results demonstrate that the penetration velocities are considerably lower than those that might be observed in play. As peak-grille gap settings were reduced, penetration velocities increased as expected but, significantly, balls were able to penetrate despite gap settings, on occasion being considerably smaller than the ball diameter. The penetration velocity was also found, as expected, to vary with the stiffness of the ball with increased ball stiffness leading to reduced penetration velocities. When comparing penetration velocities against those found using the alternate methodologies, significant differences were found, suggesting that such methodologies cannot be used to reliably evaluate the performance of helmets to ball impacts occurring in this particular region.
Wang, W, Li, Z, Wang, Y & Chen, F 1970, 'Indexing cognitive workload based on pupillary response under luminance and emotional changes', Proceedings of the 2013 international conference on Intelligent user interfaces, IUI '13: 18th International Conference on Intelligent User Interfaces, ACM, pp. 247-256.
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Pupillary response is a popular physiological index of cognitive workload that can be used for design and evaluation of adaptive interface in various areas of human-computer interaction (HCI) research. However, in practice various confounding factors unrelated to workload, including changes of luminance condition and emotional arousal might degrade pupillary response based workload measures such as commonly used mean pupil diameter. This work investigates pupillary response as a cognitive workload measure under the influence of such confounding factors. Video-based eye tracker is used to record pupillary response during arithmetic tasks under luminance and emotional changes. Machine learning based feature selection and classification techniques are proposed to robustly index cognitive workload based on pupillary response even with the influence of noisy factors unrelated to workload. Copyright © 2013 ACM.
Wang, W, Wang, Y, Chen, F & Sowmya, A 1970, 'A weakly supervised approach for object detection based on Soft-Label Boosting', 2013 IEEE Workshop on Applications of Computer Vision (WACV), 2013 IEEE Workshop on Applications of Computer Vision (WACV), IEEE, Clearwater, FL, pp. 331-338.
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Wang, Y, Li, Z, Wang, Y & Chen, F 1970, 'A Bayesian non-parametric viewpoint to visual tracking', 2013 IEEE Workshop on Applications of Computer Vision (WACV), 2013 IEEE Workshop on Applications of Computer Vision (WACV), IEEE, Clearwater, FL, pp. 482-488.
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Wi, H, Nguyen, V, Lee, J, Guan, H, Loo, YC & Blumenstein, M 1970, 'Enhancing visual-based bridge condition assessment for concrete crack evaluation using image processing techniques', Long Span Bridges and Roofs - Development, Design and Implementation, IABSE Symposium, Kolkata, India.
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Condition assessment is one of the most essential practices in bridge asset management to maintain the safety and durability of structures. Routine bridge inspection, a visual-based method, is regularly performed by qualified inspectors to determine the condition of individual bridge elements manually using bridge inspection standards. However, the quality of a visual-based condition assessment relies heavily on the inspector's knowledge and experience. The research presented here focuses on the development of an enhanced method to minimise the shortcomings of visual-based inspection. In this paper, we investigate the performance of RBF-kernel support vector machines (SVMs), a supervised machine learning technique, to increase the reliability of visual-based bridge inspection. The results of this study can contribute to minimising the shortcomings of current visual-based bridge inspection practices.
Wi, H, Nguyen, V, Lee, J, Guan, H, Loo, Y-C & Blumenstein, M 1970, 'Enhancing Visual-based Bridge Condition Assessment for Concrete Crack Evaluation Using Image Processing Techniques', IABSE Symposium, Kolkata 2013: Long Span Bridges and Roofs - Development, Design and Implementation, IABSE Symposium, Kolkata 2013: Long Span Bridges and Roofs - Development, Design and Implementation, International Association for Bridge and Structural Engineering (IABSE).
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<p>Condition assessment is one of the most essential practices in bridge asset management to maintain the safety and durability of structures. Routine bridge inspection, a visual-based method, is regularly performed by qualified inspectors to determine the condition of individual bridge elements manually using bridge inspection standards. However, the quality of a visual-based condition assessment relies heavily on the inspector’s knowledge and experience. The research presented here focuses on the development of an enhanced method to minimise the shortcomings of visual-based inspection. In this paper, we investigate the performance of RBF-kernel support vector machines (SVMs), a supervised machine learning technique, to increase the reliability of visual- based bridge inspection. The results of this study can contribute to minimising the shortcomings of current visual-based bridge inspection practices.</p>
Wijayaratna, K, Dixit, V, Mao, T & Waller, ST 1970, 'Emissions impacts of transit signal prioritisation', Australasian Transport Research Forum, ATRF 2013 - Proceedings.
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The environmental implications of transport planning and infrastructure have become an important consideration across the last decade. Significant research has been carried out to identify methods to reduce the impact of transportation systems, in particular surface transportation systems, on the environment. Transit signal prioritisation has been widely used throughout mass-transit systems to ensure schedule adherence and reduce delays for transit vehicles, primarily buses at a minimised cost to other vehicles on the network. However these systems do not take into consideration the impact on the level of emissions created by the signal prioritisation scenario. The paper demonstrates the emissions impact of a standard Transit Signal Priority (TSP) application simulated using the microsimulation tool, Paramics on the corridor network of El Camino Real, CA. Environmental performance data was collected using the emissions modelling tool 'Paramics Monitor' and the results of the simulation indicate that even though emissions levels of busses reduce, the overall level of emissions tend to increase with the implementation of TSP. Accordingly the research study further proposes a methodology for the determination of real time transit signal prioritisation optimisation model with the primary aim to minimise the environmental impact (emissions and fuel consumption). In other words, this will in the future result in the development of an Eco-Transit Signal Prioritisation application. The provision of priority considers a number of parameters including the vehicle's location, speed, vehicle type as well as emissions (such as greenhouse gasses) and fuel consumption. In addition schedule adherence and the number of passengers on board also serve as important factors affecting both the level of emissions as well as delays experienced.
Wijayaratna, KP, Duell, M & Waller, ST 1970, 'Predicting disrupted network behaviour incorporating user equilibrium with recourse', Proceedings of the 18th International Conference of Hong Kong Society for Transportation Studies, HKSTS 2013 - Travel Behaviour and Society, pp. 633-640.
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Disruptions to a network create uncertainty which affects the rationality of a user as well their familiarity of the road network. Accordingly traditional equilibrium concepts are not applicable when disruptions are present on a network, especially when developing models for the purposes of incident mitigation or disaster planning. To address this need, this work presents the disrupted equilibrium assignment with recourse (DEAR) model that incorporates a decision-making process in which users gain information about the uncertainty created by a disruption as they travel though the network. The core of the work builds on an existing static, Disrupted Network Assignment Model (DNAM) by incorporating and adaptation of the user equilibrium with recourse (UER) model. Demonstration of the model methodology is presented on a simple network with results indicating the necessity to account for the adaptive behaviour of users in light of a disruption.
Yang, C, Sheng, D & Carter, JP 1970, 'Stochastic Analysis of Hydraulic Hysteresis in Multi-Layer Unsaturated Soil Covers Under Random Flux Boundary Conditions', Foundation Engineering in the Face of Uncertainty, Geo-Congress 2013, American Society of Civil Engineers.
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Zhang, Z, Oberst, S & Lai, JCS 1970, 'Application of polynomial chaos expansions to analytical models of friction oscillators', Annual Conference of the Australian Acoustical Society 2013, Acoustics 2013: Science, Technology and Amenity, Annual Conference of the Australian Acoustical Society, Victor Harbor, Australia, pp. 408-414.
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Despite past substantial research efforts, the prediction of brake squeal propensity remains a largely unresolved problem. The standard practice to predict the brake squeal propensity is to analyse dynamic instabilities using the complex eigenvalue analysis. However, it is well known that not every predicted unstable vibration mode will lead to squeal and vice-versa. Owing to nonlinearity and problem complexity (e.g. operating conditions), treating brake squeal with uncertainty seems appealing. Another indicator of brake squeal propensity, not often used, is based on negative dissipated energy. In this study, uncertainty analysis induced by polynomial chaos expansions is examined for 1-dof and 4-dof friction models. Results are compared with dissipated energy calculations and standard complex eigenvalue analysis. The potential of this approach for the prediction of brake squeal propensity is discussed. © (2013) by the Australian Acoustical Society.
Zhou, AN & Sheng, D 1970, 'Modelling Hydro-Mechanical Interactive Behaviour of Unsaturated Soils', Poromechanics V, Fifth Biot Conference on Poromechanics, American Society of Civil Engineers, pp. 1550-1559.
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This paper presents an alternative approach for interpreting unsaturated soil behaviour, which is built in the space of stress versus degree of saturation. A new volume change equation is proposed in terms of stress and degree of saturation, to give a better explanation to the non-linear change of soil compressibility under constant suctions. An alternative approach to simulate hydraulic hysteresis and hydro-mechanical interaction is then introduced, which enables the calculation of the effective degree of saturation under complex stress and suction paths. The loading-collapse yield surface is derived based on the proposed volume change equation in the plane of the effective degree of saturation and the Bishop effective stress. The proposed volume change equation and the corresponding yield surface are generalized to three-dimensional stress states by incorporating with the Modified Cam-clay model. The proposed model is validated against a variety of experimental data in literature. © 2013 American Society of Civil Engineers.