Publications

Cetindamar, KD, James, E, Lammers, T, Pearce, A & Sullivan, E 2019, 'High-growth Women’s Entrepreneurship' in Bullough, A, Hechavarría, D, Brush, CG & Edelman, LF (eds), High-growth Women’s Entrepreneurship, Edward Elgar Publishing, pp. 78-108.
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The objective of this chapter is to draw attention to the relationship between STEM education and women’s enterprenurship in technology enterprises. By using Australia as a case study, our explorative analysis of secondary data shows how Australia has relatively improved, with gains in the level of women’s involvement in STEM education, while it still has to overcome a chasm for women then proceeding from being a STEM alumni into actually becoming an enterpreneur in technology startups. We specifically point out an institutional intervention in STEM education, the Science in Australia Gender Equity (SAGE) initiative. The chapter concludes with a discussion and suggestions for further studies.

Croaker, P, Moreau, D, Awasthi, M, Karimi, M, Doolan, C & Kessissoglou, N 2019, 'Numerical and Experimental Investigation of the Flow-Induced Noise of a Wall-Mounted Airfoil' in Flinovia—Flow Induced Noise and Vibration Issues and Aspects-II, Springer International Publishing, pp. 99-112.
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Deuse, J, Wiegand, M & Weisner, K 2019, 'Continuous Process Monitoring Through Ensemble-Based Anomaly Detection' in Studies in Classification, Data Analysis, and Knowledge Organization, Springer International Publishing, pp. 289-301.
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© Springer Nature Switzerland AG 2019. In many production processes, a complete quality inspection of all products is not feasible due to technological and organizational restrictions. In order to ensure zero-defect products, monitoring process parameters in real time and using them to predict product quality by supervised learning methods is a very established approached. However, this approach requires a joining of process parameters and quality features. In order to guarantee high-quality products even in the absence of traceability, a continuous process monitoring approach based on an anomaly detection ensemble method is beneficial.

Lammers, T, Skirde, H & Guertler, M 2019, 'Modulares Projektportfoliomanagement – Eine Vision zur Beherrschung komplexer Projektlandschaften' in Schroeder, M & Wegner, K (eds), Logistik im Wandel der Zeit – Von der Produktionssteuerung zu vernetzten Supply Chains, Springer Fachmedien Wiesbaden, Wiesbaden, pp. 791-811.
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In times of ever increasing globalization and digital change, companies operate more than ever in a highly dynamic and uncertain environment. This volatility affects both the definition of strategy and how internal and external projects are designed and carried out in order to be able to react flexibly to changes (Sarkar, 2016).

LU, S, Oberst, S, Zhang, G & Luo, Z 2019, 'Theory and Applications of Time Series Analysis' in Valenzuela, O, Rojas, F, Pomares, H & Rojas, I (eds), Theory and Applications of Time Series Analysis, Springer International Publishing, Cham, Switzerland, pp. 57-70.
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Forbidden ordinal patterns are known to be useful to discriminate between chaotic and stochastic systems. However, while uncorrelated noise can be separated from deterministic signals using forbidden ordinal patterns, correlated noise exhibits apparently forbidden ordinal patterns, which can impede distinguishing noise from chaos. Here, we introduce order patterns recurrence plots to visualise the difference among deterministic chaotic systems, and stochastic systems of uncorrelated and correlated noise. In an order pattern plot of a chaotic system with an optimal embedding dimension, the diagonal lines remain preserved, while uncorrelated noise shows up as thinly isolated dots and correlated noise forms clusters. We propose two measures, the mean and the median of relative frequencies of order patterns that appear in a time series to distinguish those dynamics. The effectiveness of the two measures is analysed using bifurcation diagrams of the logistic map, the tent map, the delayed logistic map and the Hénon map. Our results show, that both, the mean and the median, distinguish chaos from quasiperiodicity in the delayed logistic map. The mean of relative frequencies of order pattern is reciprocal to the number of order patterns that occur in a given time series and thus can be a measure of forbidden structures—which becomes unbounded. While the mean is robust to the change of parameters in the bifurcation diagrams, the median exhibits sensitive changes, which is significant to characterise chaotic signals.

Oberst, S, Lai, JCS & Evans, TA 2019, 'Biotremology: Studying Vibrational Behavior' in Hill, PSM, Lakes-Harlan, R, Mazzoni, V, Narins, PM, Virant-Doberlet, M & Wessel, A (eds), Biotremology: Studying Vibrational Behavior, Springer International Publishing, Switzerland, pp. 53-78.
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Socially living insects rely on efficient and accurate communication and source localisation for survival. Insects communicate multimodally using visual, chemical or mechanical cues. Vibrations are often considered to be a primitive mode of exchanging information, but vibrations are independent of sight or airflow, and can reach the destination cryptically and reliably. However, other than in air or water, the vibration communication channel in nature is usually a heterogeneous substrate with nonlinear material properties. Communication is hindered by increased signal complexity under the influence of noise and distortion. This chapter gives an overview of biotremology on natural substrates and the difficulties associated with noise and heterogeneous materials. The noise control engineering principle is used to extract the excitation signal from substrate response vibrations and the communication channel properties. It is argued that in order to obtain insight into the role of vibrations in insect behaviour, the ability of insects to adapt to changed situations and environmental conditions by making use of the substrate as a filter needs to be studied by means of the excitation signal rather than the response signal alone.

Webster, C, Jusufi, A & Liu, D 2019, 'A Comparative Survey of Climbing Robots and Arboreal Animals in Scaling Complex Environments' in Robotics and Mechatronics, Springer International Publishing, Switzerland, pp. 31-45.
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© Springer Nature Switzerland AG 2019. The inchworm-style climbing robot present in current literature will only take us so far towards the robotic maintenance of transmission towers. To continue to push toward developing robots that can perform work in reticular structures we must consider a broader spectrum of animals for inspiration. The abilities of Primates in climbing have long been a benchmark in climbing standards, but due to the mechanical and control complexity associated with their development, they are seldom seen in robotics. Birds (specifically Psittaciformes) offer an alternate solution, utilising less degrees-of-freedom whilst maintaining stability and maneuverability. These ancient arboreal specialists may hold they keys to unlocking the next stage in the development of climbing robotics. This work presents lessons learned from a review on primates as well as some preliminary observations on the climbing capabilities of Psittaciformes.

Abdo, P, Huynh, BP, Irga, PJ & Torpy, FR 2019, 'Evaluation of air flow through an active green wall biofilter', Urban Forestry & Urban Greening, vol. 41, pp. 75-84.
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© 2019 Elsevier GmbH Green walls show promise as active bio-filters to improve indoor air quality by removing both gaseous and particulate air pollutants. The current work represents a detailed assessment of airflow through an active green wall module. Airflow distribution through the module, the effect of wetting the substrate, and the effect of introducing a cover to the module's open top face were investigated, with the aim to improve the module's design and achieve more appropriate and effective airflow. Four cases of both planted and unplanted modules under both dry and wet conditions are considered. This work's primary observation is that more air will pass through a typical green wall substrate, and hence become cleansed, when the substrate is saturated wet more than when it is dry. The increase was substantial at approximately 50% more with 14.9 ± 0.2 L/s total air flow rate passing through the wet planted module versus 10 ± 0.2 L/s when dry. Reducing the 15.5 ± 0.75% of airflow passing through the module's open top face was found to be essential to maximize the bio-filtration capacity. Adding a top cover to the module having six 10 mm holes for irrigation decreased the airflow through the top by 6 ± 0.75%, and directed it through the filter increasing the percentage of air flow passing through the front openings from 79 ± 4% to 85 ± 4%.

Acosta, E, Smirnov, V, Szabo, PSB, Buckman, J & Bennett, NS 2019, 'Optimizing Thermoelectric Power Factor in p-Type Hydrogenated Nano-crystalline Silicon Thin Films by Varying Carrier Concentration', Journal of Electronic Materials, vol. 48, no. 4, pp. 2085-2094.
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© 2019, The Minerals, Metals & Materials Society. Most approaches to silicon-based thermoelectrics are focused on reducing the lattice thermal conductivity with minimal deterioration of the thermoelectric power factor. This study investigates the potential of p-type hydrogenated nano-crystalline silicon thin films (μc-Si:H), produced by plasma-enhanced chemical vapor deposition, for thermoelectric applications. We adopt this heterogeneous material structure, known to have a very low thermal conductivity (~ 1 W/m K), in order to obtain an optimized power factor through controlled variation of carrier concentration drawing on stepwise annealing. This approach achieves a best thermoelectric power factor of ~ 3 × 10 −4  W/mK 2 at a carrier concentration of ~ 4.5 × 10 19  cm 3 derived from a significant increase of electrical conductivity ~ × 8, alongside a less pronounced reduction of the Seebeck coefficient, while retaining a low thermal conductivity. These thin films have a good thermal and mechanical stability up to 500°C with appropriate adhesion at the film/substrate interface.

Al-Zubaydi, AYT & Hong, G 2019, 'Experimental study of a novel water-spraying configuration in indirect evaporative cooling', Applied Thermal Engineering, vol. 151, pp. 283-293.
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© 2019 Elsevier Ltd Indirect evaporative cooler (IEC) is a clean cooling device in development for air conditioning systems. It uses the water to partially replace the refrigerant and can be applied as a standalone cooling system or an energy recovery ventilation system. Driven by the concern about the sustainability, IEC has been required to reduce the power to operate and increase its capacity in order to reduce the energy consumption and increase the overall efficiency of the air condition system. The water distribution over the plate walls in the cooler is a key factor affecting the IEC performance and efficiency. This study investigates the effect of a novel suggested water spray configuration on the performance of a ventilation energy recovery IEC. Experiments were conducted to investigate three water spray modes: external spray, internal spray and mixed internal and external sprays. The results show that the mixed mode performs best and internal spraying mode performs better than the external spraying mode does in terms of the wet-bulb efficiency, cooling capacity and the COP of IEC. The mixed mode improves the performance further by increasing wettability.

Babayan, M, Mazraeh, AE, Yari, M, Niazi, NA & Saha, SC 2019, 'Hydrogen production with a photovoltaic thermal system enhanced by phase change materials, Shiraz, Iran case study', Journal of Cleaner Production, vol. 215, pp. 1262-1278.
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© 2019 Elsevier Ltd Whereas Photovoltaic Thermal Systems (PVT), Phase Change Materials (PCM) and Proton Exchange Membrane (PEM) electrolyzer have been thoroughly studied individually, the effects of their combination need to be more investigated. The current study proposed a new PVT system integrated with PCM and PEM electrolyzer to produce hydrogen in a hydrogen fuel filling station. Based on the energy and exergy balance equations, a mathematical model is developed to analyse the effects of different types of PV and PCM sets on the thermal and electrical performances. Variations in the temperature of system components, generated electricity, hydrogen production as well as the energy/exergy amounts and efficiencies with time are presented for different effective parameters. Based on the obtained results, we found that PV type is one of the most dominant parameters of the system. PCM utilization improves the electrical, thermal energies and exergy efficiencies. The highest daily amount of produced hydrogen is obtained for 16th August 2018 with mono-crystalline semitransparent PV and 120 kg of RT35 PCM type (88.71 gr/day). While the hydrogen production for the same PVT system without PCM is 5.32% less than the case with PCM. Moreover, the maximum diurnal energy efficiency is obtained 35.04% for mono-crystalline semitransparent PV and RT35 PCM during the summer, while the maximum daily exergy efficiency of 15.17% is achieved for the integration of mono-crystalline semitransparent PV and RT28 PCM type in the winter.

Bauer, D, Patten, T & Vincze, M 2019, 'VeREFINE: Integrating Object Pose Verification with Physics-guided Iterative Refinement'.
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Accurate and robust object pose estimation for robotics applications requiresverification and refinement steps. In this work, we propose to integratehypotheses verification with object pose refinement guided by physicssimulation. This allows the physical plausibility of individual object poseestimates and the stability of the estimated scene to be considered in aunified optimization. The proposed method is able to adapt to scenes ofmultiple objects and efficiently focuses on refining the most promising objectposes in multi-hypotheses scenarios. We call this integrated approach VeREFINEand evaluate it on three datasets with varying scene complexity. The generalityof the approach is shown by using three state-of-the-art pose estimators andthree baseline refiners. Results show improvements over all baselines and onall datasets. Furthermore, our approach is applied in real-world graspingexperiments and outperforms competing methods in terms of grasp success rate.Code is publicly available at github.com/dornik/verefine.

Best, G, Cliff, OM, Patten, T, Mettu, RR & Fitch, R 2019, 'Dec-MCTS: Decentralized planning for multi-robot active perception', The International Journal of Robotics Research, vol. 38, no. 2-3, pp. 316-337.
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We propose a decentralized variant of Monte Carlo tree search (MCTS) that is suitable for a variety of tasks in multi-robot active perception. Our algorithm allows each robot to optimize its own actions by maintaining a probability distribution over plans in the joint-action space. Robots periodically communicate a compressed form of their search trees, which are used to update the joint distribution using a distributed optimization approach inspired by variational methods. Our method admits any objective function defined over robot action sequences, assumes intermittent communication, is anytime, and is suitable for online replanning. Our algorithm features a new MCTS tree expansion policy that is designed for our planning scenario. We extend the theoretical analysis of standard MCTS to provide guarantees for convergence rates to the optimal payoff sequence. We evaluate the performance of our method for generalized team orienteering and online active object recognition using real data, and show that it compares favorably to centralized MCTS even with severely degraded communication. These examples demonstrate the suitability of our algorithm for real-world active perception with multiple robots.

Bhowmick, S, Saha, SC, Qiao, M & Xu, F 2019, 'Transition to a chaotic flow in a V-shaped triangular cavity heated from below', International Journal of Heat and Mass Transfer, vol. 128, pp. 76-86.
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© 2018 Elsevier Ltd Natural convection in a V-shaped cavity heated from below and cooled from top is investigated owing to its extensive presence in industrial systems and in nature such as in a valley. Two dimensional numerical simulation is performed for natural convection in the cavity using a Finite Volume Method. A wide range of Rayleigh numbers of Ra = 100 to 108 for the aspect ratio of A = 0.5 and the Prandtl number of Pr = 0.71 is considered. A set of supercritical bifurcations in a transition to a chaotic flow are described, which include a Pitchfork bifurcation from symmetric to asymmetric state and a Hopf bifurcation from steady to unsteady state. It is found that the Pitchfork bifurcation occurs between Ra = 7.5 × 103 and 7.6 × 103 and the Hopf bifurcation occurs between Ra = 1.5 × 107 and 1.6 × 107. Additionally, a further bifurcation from periodic to chaotic state occurs between Ra = 5 × 107 and 6 × 107. The power spectral density, the phase space trajectory and the largest Lyapunov exponent of unsteady flows in the transition to a chaotic state have been described. Further, heat transfer in the cavity is calculated and the corresponding dependence on the Rayleigh number is discussed and quantified.

Blamires, SJ & Sellers, WI 2019, 'Modelling temperature and humidity effects on web performance: implications for predicting orb-web spider (Argiope spp.) foraging under Australian climate change scenarios', Conservation Physiology, vol. 7, no. 1.
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Lay Summary.How climate change impacts animal extended phenotypes (EPs) is poorly understood. We modelled how temperature and humidity affects the ability of spider webs to intercept prey. We found humidity had negative effects at the extremes. Temperature, however, likely interacts with humidity to affect web tension and prey retention.

Blamires, SJ, Cerexhe, G, White, TE, Herberstein, ME & Kasumovic, MM 2019, 'Spider silk colour covaries with thermal properties but not protein structure', Journal of The Royal Society Interface, vol. 16, no. 156, pp. 20190199-20190199.
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Understanding how and why animal secretions vary in property has important biomimetic implications as desirable properties might covary. Spider major ampullate (MA) silk, for instance, is a secretion earmarked for biomimetic applications, but many of its properties vary among and between species across environments. Here, we tested the hypothesis that MA silk colour, protein structure and thermal properties covary when protein uptake is manipulated in the spider Trichonephila plumipes . We collected silk from adult female spiders maintained on a protein-fed or protein-deprived diet. Based on spectrophotometric quantifications, we classified half the silks as ‘bee visible’ and the other half ‘bee invisible’. Wide angle X-ray diffraction and differential scanning calorimetry were then used to assess the silk's protein structure and thermal properties, respectively. We found that although protein structures and thermal properties varied across our treatments only the thermal properties covaried with colour. This ultimately suggests that protein structure alone is not responsible for MA silk thermal properties, nor does it affect silk colours. We speculate that similar ecological factors act on silk colour and thermal properties, which should be uncovered to inform biomimetic programmes.

Bykerk, L, Quin, P & Liu, D 2019, 'A Method for Selecting the Next Best Angle-of-Approach for Touch-Based Identification of Beam Members in Truss Structures', IEEE Sensors Journal, vol. 19, no. 10, pp. 3939-3949.
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© 2001-2012 IEEE. A robot designed to climb truss structures such as power transmission towers is expected to have an adequate tactile sensing in the grippers to identify a structural beam member and its properties. Depending on how a gripper grasps a structural member, defined as the Angle-of-Approach (AoA), the extracted tactile data can result in erroneous identifications due to the similarities in beam cross-sectional shapes and sizes. In these cases, further grasps at favorable Angles-of-Approach (AoAs) are required to correctly identify the beam member and its properties. This paper presents an information-based method which uses tactile data to determine the next best AoA for the identification of beam members in truss structures. The method is used in conjunction with a state estimate of beam shape, dimension, and AoA calculated by a Random Forest classifier. The method is verified through simulation by using the data collected using a soft gripper retrofitted with simple tactile sensors. The results show that this method can correctly identify a structural beam member and its properties with a small number of grasps (typically fewer than 4). This method can be applied to other adaptive robotic gripper designs fitted with suitable tactile sensors, regardless of the number of sensors used and their layout.

Chen, D, Luo, Q, Meng, M, Li, Q & Sun, G 2019, 'Low velocity impact behavior of interlayer hybrid composite laminates with carbon/glass/basalt fibres', Composites Part B: Engineering, vol. 176, pp. 107191-107191.
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© 2019 Elsevier Ltd This work investigates the effects of carbon/glass/basalt hybridization and fabric structure on the low velocity impact resistance of fibre reinforced plastic composites. Interply hybrid specimens used in the study were fabricated in a sandwich-like stacking sequence using a vacuum assisted resin infusion molding technique. Low velocity impact tests were carried out to study effects of hybridization and fabric structure on the impact resistance of composite laminates. A continuum damage mechanical model was developed and validated for non-hybrid woven fabric laminates at different impact energy levels. Residual damage characteristics in the cross-sectional view were identified using a 3D surface scanning system and an X-ray computed tomography (CT) method. On the basis of experimental results, numerical simulation was conducted to analyse the damage mechanisms of the hybrid laminates. Experimental results showed that: (a) hybrid laminates with carbon fibre as the core exhibited superior impact resistance for sandwich-like stacking sequence; (b) similar impact behaviors appeared for carbon laminates hybrid with either basalt or glass fibre; (c) for basalt fibre, weave fabric composite laminates exhibited better energy absorption capability and deformation resistance than cross-ply laminates reinforced by unidirectional fabrics.

Cheng, S, Dong, H, Yu, L, Zhang, D & Ji, J 2019, 'Consensus of Second-order Multi-agent Systems with Directed Networks Using Relative Position Measurements Only', International Journal of Control, Automation and Systems, vol. 17, no. 1, pp. 85-93.
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© 2019, Institute of Control, Robotics and Systems and The Korean Institute of Electrical Engineers and Springer-Verlag GmbH Germany, part of Springer Nature. This brief paper studies the consensus problem of second-order multi-agent systems when the agents’ velocity measurements are unavailable. Firstly, two simple consensus protocols which do not need velocity measurements of the agents are derived to guarantee that the multi-agent systems achieve consensus in directed networks. Secondly, a key constant which is determined by the complex eigenvalue of the nonsymmetric Laplacian matrix and an explicit expression of the consensus state are respectively developed based on matrix theory. The obtained results show that all the agents can reach consensus if the feedback parameter is bigger than the key constant. Thirdly, the theoretical analysis shows that the followers can track the position and velocity of the leader provided that the leader has a directed path to all other followers and the feedback parameter is bigger enough. Finally, numerical simulations are given to illustrate the effectiveness of the proposed protocols.

Cheng, X, Jiang, Z, Wei, D, Wu, H & Jiang, L 2019, 'Adhesion, friction and wear analysis of a chromium oxide scale on a ferritic stainless steel', Wear, vol. 426-427, pp. 1212-1221.
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Cui, H, Xu, F, Saha, SC & Liu, Q 2019, 'Transient free convection heat transfer in a section-triangular prismatic enclosure with different aspect ratios', International Journal of Thermal Sciences, vol. 139, pp. 282-291.
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© 2019 Elsevier Masson SAS Free convection studies in a section-triangular prismatic enclosure with different aspect ratios (depth-width ratios, A) is conducted using three-dimensional numerical modeling approach. The Rayleigh number (Ra) covers a broad range from 10 0 to 10 7 . Transient free convection is characterized under top cooled and bottom heated boundary conditions. The flow structure of transverse rolls and longitudinal rolls is described. The critical Rayleigh numbers for the transition of the flow from driven by the baroclinic to Rayleigh-Bénard instability and from a steady to an unsteady state have been obtained for different aspect ratios. Free convection in the section-triangular prismatic enclosure could be divided into three regimes, which are presented in a Ra-A space. The quantitative relationship between heat transfer and the aspect ratio as well as the Rayleigh number has been obtained numerically.

Deuse, J, Schmitt, J, Bönig, J & Beitinger, G 2019, 'Dynamische Röntgenprüfung in der Elektronikproduktion', Zeitschrift für wirtschaftlichen Fabrikbetrieb, vol. 114, no. 5, pp. 264-267.
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Kurzfassung In diesem Beitrag wird ein Konzept zur dynamischen Röntgenprüfung in der Elektronikproduktion vorgestellt, das durch die Auswertung von Prozessdaten mithilfe von Data-Mining-Verfahren die Prognose der finalen Produktqualität im laufenden Prozess erlaubt. Dies ermöglicht die Reduzierung von Röntgenprüfumfängen durch die Entwicklung dynamischer Prüfpläne.

Ding, H, Ji, J & Chen, L-Q 2019, 'Nonlinear vibration isolation for fluid-conveying pipes using quasi-zero stiffness characteristics', Mechanical Systems and Signal Processing, vol. 121, no. Int. J. Non-linear Mech. 45 2010, pp. 675-688.
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© 2018 Fluid-conveying pipes are always subjected to various excitations to cause unwanted vibrations. A quasi-zero stiffness system consisting of three linear springs is adopted as the nonlinear isolator to attenuate the transverse vibrations of fluid-conveying pipes induced by foundation excitations. A dynamic model of nonlinear forced vibration of the fluid-conveying pipe coupled with two nonlinear isolators is established for the nonlinear continuous system and validated by using two methods, Galerkin method and the finite difference method. The influence of the quasi-zero stiffness isolators on the vibration characteristics and vibration transmission of the pipe is investigated by analyzing the natural frequency, vibration mode, and nonlinear vibration response. The effects of flow speed of the fluid and the system parameters of the isolator are studied to evaluate the isolation performance. It is found that the quasi-zero stiffness isolator and fluid flow can shift several natural frequencies of vibration of the pipeline to the low-frequency region. When the linear stiffness of the vibration isolation is zero in the vertical direction, the first two modes of the bending vibration of the fluid-conveying pipe tend to become rigid mode. While achieving high-efficiency vibration isolation in the high-frequency region, the vibration in the low-frequency region is complicated. The flow speed of the fluid can deteriorate the performance of vibration isolation.

Eager, D & Hayati, H 2019, 'Additional Injury Prevention Criteria for Impact Attenuation Surfacing Within Children's Playgrounds', ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part B: Mechanical Engineering, vol. 5, no. 1.
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More than four decades have passed since the introduction of safety standards for impact attenuation surfaces (IAS) used in playgrounds. Falls in children's playground are a major source of injuries and IAS is one of the best methods of preventing severe head injuries. However, the ability of IAS in prevention of other types of injuries, such as upper limb fractures, is unclear. Accordingly, in this paper, ten synthetic playground surfaces were tested to examine their performance beyond the collected head injury criterion (HIC) and maximum G-force (Gmax) outputs recommended by ASTM F1292. The aim of this work was to investigate any limitations with current safety criteria and proposing additional criteria to filter hazardous IAS that technically comply with the current 1000 HIC and 200 Gmax thresholds. The proposed new criterion is called the impulse force criterion (If). If combines two important injury predictor characteristics, namely: HIC duration that is time duration of the most severe impact; and the change in momentum that addresses the IAS properties associated with bounce. Additionally, the maximum jerk (Jmax), the bounce, and the IAS absorbed work are presented. HIC, Gmax, If, and Jmax followed similar trends regarding material thickness and drop height. Moreover, the bounce and work done by the IAS on the falling missile at increasing drop heights was similar for all surfaces apart from one viscoelastic foam sample. The results presented in this paper demonstrate the limitations of current safety criteria and should, therefore, assist future research to reduce long-bone injuries in playgrounds.

Eickelmann, M, Wiegand, M, Deuse, J & Bernerstätter, R 2019, 'Bewertungsmodell zur Analyse der Datenreife', Zeitschrift für wirtschaftlichen Fabrikbetrieb, vol. 114, no. 1-2, pp. 29-33.
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Kurzfassung Die digitale Transformation der Unternehmensprozesse führt zu einem stetigen Anstieg verfügbarer Daten. Zur effizienten Nutzung des in den Daten verborgenen Wissens streben Unternehmen den Einsatz maschineller Lernverfahren an. Die Datenqualität hat eine herausragende Bedeutung für die Anwendbarkeit maschineller Lernverfahren sowie die resultierende Güte der Ergebnisse. Dieser Beitrag präsentiert ein Modell zur Bewertung der Datenreife, das die Evaluierung der Erfolgs-chancen industrieller Datenanalyseprojekte ermöglicht und Hinweise auf erforderliche Schritte zur Verbesserung der Datenreife gibt.

Gao, C, Ji, J, Yan, F & Liu, H 2019, 'Oscillation induced by Hopf bifurcation in the p53–Mdm2 feedback module', IET Systems Biology, vol. 13, no. 5, pp. 251-259.
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This study develops an integrated model of the p53-Mdm2 interaction composed of five basic components and time delay in the DNA damage response based on the existing research work. Some critical factors, including time delay, system parameters, and their interactions in the p53-Mdm2 system are investigated to examine their effects on the oscillatory behaviour induced by Hopf bifurcation. It is shown that the positive feedback formed between p53 and the activity of Mdm2 in the cytoplasm can cause a slight decrease in the amplitude of the p53 oscillation. The length of the time delay plays an important role in determining the amplitude and period of the oscillation and can significantly extend the parameter range for the system to demonstrate oscillatory behaviour. The numerical simulation results are found to be in good agreement with the published experimental observation. It is expected that the results of this research would be helpful to better understand the biological functions of p53 pathway and provide some clues in the treatment of cancer.

Gao, J, Gao, L, Luo, Z & Li, P 2019, 'Isogeometric topology optimization for continuum structures using density distribution function', International Journal for Numerical Methods in Engineering, vol. 119, no. 10, pp. 991-1017.
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SummaryThis paper will propose a more effective and efficient topology optimization method based on isogeometric analysis, termed as isogeometric topology optimization (ITO), for continuum structures using an enhanced density distribution function (DDF). The construction of the DDF involves two steps. (1) Smoothness: the Shepard function is firstly utilized to improve the overall smoothness of nodal densities. Each nodal density is assigned to a control point of the geometry. (2) Continuity: the high‐order NURBS basis functions are linearly combined with the smoothed nodal densities to construct the DDF for the design domain. The nonnegativity, partition of unity, and restricted bounds [0, 1] of both the Shepard function and NURBS basis functions can guarantee the physical meaning of material densities in the design. A topology optimization formulation to minimize the structural mean compliance is developed based on the DDF and isogeometric analysis to solve structural responses. An integration of the geometry parameterization and numerical analysis can offer the unique benefits for the optimization. Several 2D and 3D numerical examples are performed to demonstrate the effectiveness and efficiency of the proposed ITO method, and the optimized 3D designs are prototyped using the Selective Laser Sintering technique.

Gao, J, Luo, Z, Li, H & Gao, L 2019, 'Topology optimization for multiscale design of porous composites with multi-domain microstructures', Computer Methods in Applied Mechanics and Engineering, vol. 344, pp. 451-476.
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© 2018 Elsevier B.V. This paper proposes a new multiscale topology optimization method for the design of porous composites composed of the multi-domain material microstructures considering three design elements: the topology of the macrostructure, the topologies of multiple material microstructures and their overall distribution in the macrostructure. The multiscale design involves two optimization stages: the free material distribution optimization and the concurrent topology optimization. Firstly, the variable thickness sheet (VTS) method with the regularization mechanism is used to generate multiple element density distributions in the macro design domain. Hence, different groups of elements with the identical densities can be uniformly arranged in their corresponding domains, and each domain in the space will be periodically configured by a unique representative microstructure. Secondly, with the discrete material distributions achieved in the macro domain, the topology of the macrostructure and topologies of multiple representative microstructures are concurrently optimized by a parametric level set method combined with the numerical homogenization method. Finally. Several 2D and 3D numerical examples are provided to demonstrate the effectiveness of the proposed multiscale topology optimization method.

Gao, J, Luo, Z, Li, H, Li, P & Gao, L 2019, 'Dynamic multiscale topology optimization for multi-regional micro-structured cellular composites', Composite Structures, vol. 211, pp. 401-417.
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© 2018 Elsevier Ltd In this paper, a new dynamic multiscale topology optimization method for cellular composites with multi-regional material microstructures is proposed to improve the structural performance. Firstly, a free-material distribution optimization method (FMDO) is developed to generate the overall configuration for the discrete element densities distributed within a multi-regional pattern. The macrostructure is divided into several sub regions, and each of them consists of a number of elements but with the same densities. Secondly, a dynamic topology optimization formulation is developed to perform the concurrent design of the macrostructure and material microstructures, subject to the multi-regional distributed element densities. A parametric level set method is employed to optimize the topologies of the macrostructure and material microstructures, with the effective macroscopic properties evaluated by the homogenization. In the numerical implementation, the quasi-static Ritz vector (QSRV) method is incorporated into the finite element analysis so as to reduce the computational cost in numerical analysis, and some kinematical connectors are introduced to make sure the connectivity between adjacent material microstructures. Finally, 2D and 3D numerical examples are tested to demonstrate the effectiveness of the proposed dynamic multiscale topology optimization method for the material-structural composites.

Gao, J, Xue, H, Gao, L & Luo, Z 2019, 'Topology optimization for auxetic metamaterials based on isogeometric analysis', Computer Methods in Applied Mechanics and Engineering, vol. 352, pp. 211-236.
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© 2019 Elsevier B.V. In this paper, an effective and efficient topology optimization method, termed as Isogeometric Topology Optimization (ITO), is proposed for systematic design of both 2D and 3D auxetic metamaterials based on isogeometric analysis (IGA). Firstly, a density distribution function (DDF)with the desired smoothness and continuity, to represent the topological changes of structures, is constructed using the Shepard function and non-uniform rational B-splines (NURBS)basis functions. Secondly, an energy-based homogenization method (EBHM)to evaluate material effective properties is numerically implemented by IGA, with the imposing of the periodic boundary formulation on material microstructure. Thirdly, a topology optimization formulation for 2D and 3D auxetic metamaterials is developed based on the DDF, where the objective function is defined as a combination of the homogenized elastic tensor and the IGA is applied to solve the structural responses. A relaxed optimality criteria (OC)method is used to update the design variables, due to the non-monotonic property of the problem. Finally, several numerical examples are used to demonstrate the effectiveness and efficiency of the proposed method. A series of auxetic microstructures with different deformation mechanisms (e.g. the re-entrant and chiral)can be obtained. The auxetic behavior of material microstructures are numerically validated using ANSYS, and the optimized designs are prototyped using the Selective Laser Sintering (SLS)technique.

Geekiyanage, NM, Balanant, MA, Sauret, E, Saha, S, Flower, R, Lim, CT & Gu, Y 2019, 'A coarse-grained red blood cell membrane model to study stomatocyte-discocyte-echinocyte morphologies', PLOS ONE, vol. 14, no. 4, pp. e0215447-e0215447.
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© 2019 Geekiyanage et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. An improved red blood cell (RBC) membrane model is developed based on the bilayer coupling model (BCM) to accurately predict the complete sequence of stomatocyte-discocyteechinocyte (SDE) transformation of a RBC. The coarse-grained (CG)-RBC membrane model is proposed to predict the minimum energy configuration of the RBC from the competition between lipid-bilayer bending resistance and cytoskeletal shear resistance under given reference constraints. In addition to the conventional membrane surface area, cell volume and bilayer-leaflet-area-difference constraints, a new constraint: Total-membrane-curvature is proposed in the model to better predict RBC shapes in agreement with experimental observations. A quantitative evaluation of several cellular measurements including length, thickness and shape factor, is performed for the first time, between CGRBC model predicted and three-dimensional (3D) confocal microscopy imaging generated RBC shapes at equivalent reference constraints. The validated CG-RBC membrane model is then employed to investigate the effect of reduced cell volume and elastic length scale on SDE transformation, to evaluate the RBC deformability during SDE transformation, and to identify the most probable RBC cytoskeletal reference state. The CG-RBC membrane model can predict the SDE shape behaviour under diverse shape-transforming scenarios, in-vitro RBC storage, microvascular circulation and flow through microfluidic devices.

Ghaffari Jadidi, M, Valls Miro, J & Dissanayake, G 2019, 'Sampling-based incremental information gathering with applications to robotic exploration and environmental monitoring', The International Journal of Robotics Research, vol. 38, no. 6, pp. 658-685.
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We propose a sampling-based motion-planning algorithm equipped with an information-theoretic convergence criterion for incremental informative motion planning. The proposed approach allows dense map representations and incorporates the full state uncertainty into the planning process. The problem is formulated as a constrained maximization problem. Our approach is built on rapidly exploring information-gathering algorithms and benefits from the advantages of sampling-based optimal motion-planning algorithms. We propose two information functions and their variants for fast and online computations. We prove an information-theoretic convergence for an entire exploration and information-gathering mission based on the least upper bound of the average map entropy. A natural automatic stopping criterion for information-driven motion control results from the convergence analysis. We demonstrate the performance of the proposed algorithms using three scenarios: comparison of the proposed information functions and sensor configuration selection, robotic exploration in unknown environments, and a wireless signal strength monitoring task in a lake from a publicly available dataset collected using an autonomous surface vehicle.

Gu, Q, Qi, S, Yue, Y, Shen, J, Zhang, B, Sun, W, Qian, W, Islam, MS, Saha, SC & Wu, J 2019, 'Structural and functional alterations of the tracheobronchial tree after left upper pulmonary lobectomy for lung cancer', BioMedical Engineering OnLine, vol. 18, no. 1.
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Abstract Background Pulmonary lobectomy has been a well-established curative treatment method for localized lung cancer. After left upper pulmonary lobectomy, the upward displacement of remaining lower lobe causes the distortion or kink of bronchus, which is associated with intractable cough and breathless. However, the quantitative study on structural and functional alterations of the tracheobronchial tree after lobectomy has not been reported. We sought to investigate these alterations using CT imaging analysis and computational fluid dynamics (CFD) method. Methods Both preoperative and postoperative CT images of 18 patients who underwent left upper pulmonary lobectomy are collected. After the tracheobronchial tree models are extracted, the angles between trachea and bronchi, the surface area and volume of the tree, and the cross-sectional area of left lower lobar bronchus are investigated. CFD method is further used to describe the airflow characteristics by the wall pressure, airflow velocity, lobar flow rate, etc. Results It is found that the angle between the trachea and the right main bronchus increases after operation, but the angle with the left main bronchus decreases. No significant alteration is observed for the surface area or volume of the tree between pre-operation and post-operation. After left upper pulmonary lobectomy, the cross-sectional area of left lower lobar bronchus is reduced for most of the patients (15/18) by 15–75%, especially for 4 patients by more than 50%. The wall pressure, airflow velocity and pressure drop significantly increase after the operation. The flow rat...

Guertler, M, Sick, N & Kriz, A 2019, 'A Discipline-Spanning Overview of Action Research and Its Implications for Technology and Innovation Management', Technology Innovation Management Review, vol. 9, no. 4, pp. 48-65.
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The iterative and learning character of action research is particularly beneficial for exploring complex socio-technical problems in technology and innovation management (TIM). In this respect, action research allows both rigorous and relevant research due to parallel solving of real-world problems, capability building, and gaining scientific insights. However, the use of action research within TIM research is surprisingly limited. Action research also is not a homogeneous research methodology since each research discipline, such as education and organizational science, has its own action research streams, which are often only loosely linked. A systematic overview of those action research traditions and specific best practices is still missing, which complicates a systematic transfer and use of action research in TIM. This article addresses this essential gap by building a cross-disciplinary overview of action research streams based on a bibliometric analysis using Scopus. The analysis includes relevant disciplines with action research traditions, their development over time, and the most influential journals, authors, institutions, and countries. Along with this discipline-spanning analysis, the article investigates particular TIM benefits and challenges of action research. The two key contributions of this article are: 1) a discipline-spanning overview of action research and its evolution and 2) an analysis of its implications for TIM research. These contributions build the basis for strengthening the use of action research in TIM. In the medium-term, action research has the capacity to link academia and industry more closely and, in doing so, assists important endeavours of translating more of our research outcomes into practice.

Hasan, M, Zhao, J, Huang, Z, Wei, D & Jiang, Z 2019, 'Analysis and characterisation of WC-10Co and AISI 4340 steel bimetal composite produced by powder–solid diffusion bonding', The International Journal of Advanced Manufacturing Technology, vol. 103, no. 9-12, pp. 3247-3263.
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© 2019, Springer-Verlag London Ltd., part of Springer Nature. Cermet and steel material bonding is a challenging task, due to their large difference of physical properties, e.g. coefficient of thermal expansion. In this study, a hot compaction diffusion bonding method was employed to fabricate a small-dimensional bimetallic composite of WC-10Co and high strength AISI 4340 steel, where the cermet was used in powder form and the steel as solid. The bimetal composite was characterised by microstructural analysis and mechanical properties evaluation. The interface microstructure reveals a successful metallurgical bonding between the cermet and steel materials. The influence of sintering temperature (1050–1250 °C) was examined at intervals of 50 °C. This study shows that the properties of sintered powder and the bonding quality with the steel improve with an increase in sintering temperature. A bonding beneficiary reaction layer was observed to grow at the joining interface by mutual diffusion of the alloying elements, which increases with the increasing temperature. The maximum width of the reaction layer observed was 4.13 μm and consists mainly of intermetallic ternary carbides. The bonding shear strength of the interface is found to be slightly higher than claimed in previous studies. The developed bimetal composite could be used in applications where a combination of high strength and hardness is required.

Hassan, M, Liu, D & Xu, D 2019, 'A Two-Stage Approach to Collaborative Fiber Placement through Coordination of Multiple Autonomous Industrial Robots', Journal of Intelligent & Robotic Systems, vol. 95, no. 3-4, pp. 915-933.
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© 2018, Springer Nature B.V. The use of multiple Autonomous Industrial Robots (AIRs) as opposed to a single AIR to perform fiber placement brings about many challenges which have not been addressed by researchers. These challenges include optimal division and allocation of the work and performing path planning in a coordinated manner while considering the requirements and constraints that are unique to the fiber placement task. To solve these challenges, a two-stage approach is proposed in this paper. The first stage considers multiple objectives to optimally allocate each AIR with surface areas, while the second stage aims to generate coordinated paths for the AIRs. Within each stage, mathematical models are developed with several unique objectives and constraints that are specific to the multi-AIR collaborative fiber placement. Several case studies are presented to validate the approach and the proposed mathematical models. Comparison studies with different number of AIRs and variations of the developed mathematical models are also presented.

Hayati, H, Eager, D & Walker, P 2019, 'The effects of surface compliance on greyhound galloping dynamics', Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics, vol. 233, no. 4, pp. 1033-1043.
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Greyhounds are the fastest breed of dog and can reach a speed up to 68 km/h. These racing animals sustain unique injuries seldom seen in other breeds of dog. The highest rate of life-threatening injuries in these dogs is hock fracture, mostly of the right hind-leg. One of the main injury contributing factors in this sport is the track surface. There are some studies into the ideal track surface composition for greyhound racing but almost no study has investigated the body–surface interaction. Accordingly, the purpose of this work is to study the effect of surface compliance on the galloping dynamics of greyhounds during the hind-leg single-support phase which is a critical phase in hock injuries. Thus, a three degrees-of-freedom model for the greyhound body and substrate surface is designed using spring-loaded inverted pendulum method. The results showed that forces acting on the hind-leg were substantially affected when the surface compliance altered from the relatively hard (natural grass) to a relatively soft surface (synthetic rubber). The main contribution of this work is designing a mathematical model to predict the dynamics of the hock and the hind-leg as the most vulnerable body parts in greyhounds. Furthermore, this model can be used to optimise the greyhound track surface composition and therefore improve the safety and welfare within the greyhound racing industry.

Hayati, H, Mahdavi, F & Eager, D 2019, 'Analysis of Agile Canine Gait Characteristics Using Accelerometry', Sensors, vol. 19, no. 20, pp. 4379-4379.
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The high rate of severe injuries associated with racing greyhounds poses a significant problem for both animal welfare and the racing industry. Using accelerometry to develop a better understanding of the complex gait of these agile canines may help to eliminate injury contributing factors. This study used a single Inertial Measurement Unit (IMU) equipped with a tri-axial accelerometer to characterise the galloping of thirty-one greyhounds on five different race tracks. The dorsal-ventral and anterior-posterior accelerations were analysed in both the time and frequency domains. The fast Fourier transform (FFT) and Morlet wavelet transform were applied to signals. The time-domain signals were synced with the corresponding high frame rate videos of the race. It was observed that the acceleration peaks in the dorsal-ventral accelerations correspond to the hind-leg strikes which were noted to be fifteen times the greyhound’s weight. The FFT analysis showed that the stride frequencies in all tracks were around 3.5 Hz. The Morlet wavelet analysis also showed a reduction in both the frequency and magnitude of signals, which suggests a speed reduction throughout the race. Also, by detecting abrupt changes along the track, the wavelet analysis highlighted potentially hazardous locations on the track. In conclusion, the methods applied in this research contribute to animal safety and welfare by eliminating the factors leading to injuries through optimising the track design and surface type.

Henke, T & Deuse, J 2019, 'Arbeitsfortschrittssynchrone Materialbereitstellung in der Großgerätemontage', ZWF Zeitschrift für wirtschaftlichen Fabrikbetrieb, vol. 114, no. 5, pp. 243-246.
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Since the assembly of large-scale products is strongly influenced by the customer, the products have an unique character. Contract manufacturing is characterized by a low level of standardization and a high share of non-value adding activities with negative effects on throughput times and on-time delivery. In the research project SySMaG the IPS (Dortmund) therefore developed a planning framework to standardize the material supply in large scale assembly and to reduce non-value adding activities.

Hodges, J, Attia, T, Arukgoda, J, Kang, C, Cowden, M, Doan, L, Ranasinghe, R, Abdelatty, K, Dissanayake, G & Furukawa, T 2019, 'Multistage bayesian autonomy for high‐precision operation in a large field', Journal of Field Robotics, vol. 36, no. 1, pp. 183-203.
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AbstractThis paper presents a generalized multistage bayesian framework to enable an autonomous robot to complete high‐precision operations on a static target in a large field. The proposed framework consists of two multistage approaches, capable of dealing with the complexity of high‐precision operation in a large field to detect and localize the target. In the multistage localization, locations of the robot and the target are estimated sequentially when the target is far away from the robot, whereas these locations are estimated simultaneously when the target is close. A level of confidence (LOC) for each detection criterion of a sensor and the associated probability of detection (POD) of the sensor are defined to make the target detectable with different LOCs at varying distances. Differential entropies of the robot and target are used as a precision metric for evaluating the performance of the proposed approach. The proposed multistage observation and localization approaches were applied to scenarios using an unmanned ground vehicle (UGV) and an unmanned aerial vehicle (UAV). Results with the UGV in simulated environments and then real environments show the effectiveness of the proposed approaches to real‐world problems. A successful demonstration using the UAV is also presented.

Hossain, SI, Gandhi, NS, Hughes, ZE & Saha, SC 2019, 'Computational Modelling of the Interaction of Gold Nanoparticle with Lung Surfactant Monolayer', MRS Advances, vol. 4, no. 20, pp. 1177-1185.
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Copyright © Materials Research Society 2019. Lung surfactant (LS), a thin layer of phospholipids and proteins inside the alveolus of the lung is the first biological barrier to inhaled nanoparticles (NPs). LS stabilizes and protects the alveolus during its continuous compression and expansion by fine-Tuning the surface tension at the air-water interface. Previous modelling studies have reported the biophysical function of LS monolayer and its role, but many open questions regarding the consequences and interactions of airborne nano-sized particles with LS monolayer remain. In spite of gold nanoparticles (AuNPs) having a paramount role in biomedical applications, the understanding of the interactions between bare AuNPs (as pollutants) and LS monolayer components still unresolved. Continuous inhalation of NPs increases the possibility of lung ageing, reducing the normal lung functioning and promoting lung malfunction, and may induce serious lung diseases such as asthma, lung cancer, acute respiratory distress syndrome, and more. Different medical studies have shown that AuNPs can disrupt the routine lung functions of gold miners and promote respiratory diseases. In this work, coarse-grained molecular dynamics simulations are performed to gain an understanding of the interactions between bare AuNPs and LS monolayer components at the nanoscale. Different surface tensions of the monolayer are used to mimic the biological process of breathing (inhalation and exhalation). It is found that the NP affects the structure and packing of the lipids by disordering lipid tails. Overall, the analysed results suggest that bare AuNPs impede the normal biophysical function of the lung, a finding that has beneficial consequences to the potential development of treatments of various respiratory diseases.

Hossain, SI, Gandhi, NS, Hughes, ZE, Gu, YT & Saha, SC 2019, 'Molecular insights on the interference of simplified lung surfactant models by gold nanoparticle pollutants', Biochimica et Biophysica Acta (BBA) - Biomembranes, vol. 1861, no. 8, pp. 1458-1467.
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Inhaled nanoparticles (NPs) are experienced by the first biological barrier inside the alveolus known as lung surfactant (LS), a surface tension reducing agent, consisting of phospholipids and proteins in the form of the monolayer at the air-water interface. The monolayer surface tension is continuously regulated by the alveolus compression and expansion and protects the alveoli from collapsing. Inhaled NPs can reach deep into the lungs and interfere with the biophysical properties of the lung components. The interaction mechanisms of bare gold nanoparticles (AuNPs) with the LS monolayer and the consequences of the interactions on lung function are not well understood. Coarse-grained molecular dynamics simulations were carried out to elucidate the interactions of AuNPs with simplified LS monolayers at the nanoscale. It was observed that the interactions of AuNPs and LS components deform the monolayer structure, change the biophysical properties of LS and create pores in the monolayer, which all interfere with the normal lungs function. The results also indicate that AuNP concentrations >0.1 mol% (of AuNPs/lipids) hinder the lowering of the LS surface tension, a prerequisite of the normal breathing process. Overall, these findings could help to identify the possible consequences of airborne NPs inhalation and their contribution to the potential development of various lung diseases.

Islam, MS, Saha, SC, Gemci, T, Yang, IA, Sauret, E, Ristovski, Z & Gu, YT 2019, 'Euler-Lagrange Prediction of Diesel-Exhaust Polydisperse Particle Transport and Deposition in Lung: Anatomy and Turbulence Effects', Scientific Reports, vol. 9, no. 1, p. 12423.
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AbstractIn clinical assessments, the correlation between atmospheric air pollution and respiratory damage is highly complicated. Epidemiological studies show that atmospheric air pollution is largely responsible for the global proliferation of pulmonary disease. This is particularly significant, since most Computational Fluid Dynamics (CFD) studies to date have used monodisperse particles, which may not accurately reflect realistic inhalation patterns, since atmospheric aerosols are mostly polydisperse. The aim of this study is to investigate the anatomy and turbulent effects on polydisperse particle transport and deposition (TD) in the upper airways. The Euler-Lagrange approach is used for polydisperse particle TD prediction in both laminar and turbulent conditions. Various anatomical models are adopted to investigate the polydisperse particle TD under different flow conditions. Rossin-Rammler diameter distribution is used for the distribution of the initial particle diameter. The numerical results illustrate that airflow rate distribution at the right lung of a realistic model is higher than a non-realistic model. The CFD study also shows that turbulence effects on deposition are higher for larger diameter particles than with particles of smaller diameter. A significant amount of polydisperse particles are also shown to be deposited at the tracheal wall for CT-based model, whereas particles are mostly deposited at the carinal angle for the non-realistic model. A comprehensive, polydisperse particle TD analysis would enhance understanding of the realistic deposition pattern and decrease unwanted therapeutic aerosol deposition at the extrathoracic airways.

Islam, MS, Saha, SC, Sauret, E, Ong, H, Young, P & Gu, YT 2019, 'Euler–Lagrange approach to investigate respiratory anatomical shape effects on aerosol particle transport and deposition', Toxicology Research and Application, vol. 3, pp. 239784731989467-239784731989467.
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An accurate knowledge of the pulmonary aerosol particle transport in the realistic lung is essential to deliver the therapeutic particle to the targeted site of the bifurcating airways. The available in silico studies have enriched the knowledge of the aerosol transport and deposition (TD) in the lung; however, the absolute TD data in the realistic lung airway are still elusive. Therefore, in this study, a 3-D geometry of the human lung central airway is developed from the computed tomography (CT) images. A CT scan-based modified lung geometry with a smooth surface and nonrealistic Weibel’s lung geometry is also generated. The coal mine exhausted aerosol TD in the upper airway is investigated. The Euler–Lagrange (E-L) method for particle tracking and ANSYS Fluent solver are used to carry out the entire investigation. The effective diameter method is employed to define the shape-specific particles and is integrated with the E-L method. The anatomical shape effects on the deposition patterns are investigated for different deposition parameter. The numerical results illustrated that the airway geometry, particle shape, particle diameter, and breathing flow rates significantly influence the aerosol TD pattern in the upper airway. The present study reports that airway tracheal wall is the new deposition hot spot for the CT-based geometry instead of bifurcating area for the idealized model, which might be helpful for zone-specific drug delivery to the respiratory airways.

Karimi, M, Croaker, P, Skvortsov, A, Moreau, D & Kessissoglou, N 2019, 'Numerical prediction of turbulent boundary layer noise from a sharp‐edged flat plate', International Journal for Numerical Methods in Fluids, vol. 90, no. 10, pp. 522-543.
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SummaryAn efficient hybrid uncorrelated wall plane waves–boundary element method (UWPW‐BEM) technique is proposed to predict the flow‐induced noise from a structure in low Mach number turbulent flow. Reynolds‐averaged Navier‐Stokes equations are used to estimate the turbulent boundary layer parameters such as convective velocity, boundary layer thickness, and wall shear stress over the surface of the structure. The spectrum of the wall pressure fluctuations is evaluated from the turbulent boundary layer parameters and by using semi‐empirical models from literature. The wall pressure field underneath the turbulent boundary layer is synthesized by realizations of uncorrelated wall plane waves (UWPW). An acoustic BEM solver is then employed to compute the acoustic pressure scattered by the structure from the synthesized wall pressure field. Finally, the acoustic response of the structure in turbulent flow is obtained as an ensemble average of the acoustic pressures due to all realizations of uncorrelated plane waves. To demonstrate the hybrid UWPW‐BEM approach, the self‐noise generated by a flat plate in turbulent flow with Reynolds number based on chord Rec = 4.9 × 105 is predicted. The results are compared with those obtained from a large eddy simulation (LES)‐BEM technique as well as with experimental data from literature.

Khosoussi, K, Giamou, M, Sukhatme, GS, Huang, S, Dissanayake, G & How, JP 2019, 'Reliable Graphs for SLAM', The International Journal of Robotics Research, vol. 38, no. 2-3, pp. 260-298.
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Estimation-over-graphs (EoG) is a class of estimation problems that admit a natural graphical representation. Several key problems in robotics and sensor networks, including sensor network localization, synchronization over a group, and simultaneous localization and mapping (SLAM) fall into this category. We pursue two main goals in this work. First, we aim to characterize the impact of the graphical structure of SLAM and related problems on estimation reliability. We draw connections between several notions of graph connectivity and various properties of the underlying estimation problem. In particular, we establish results on the impact of the weighted number of spanning trees on the D-optimality criterion in 2D SLAM. These results enable agents to evaluate estimation reliability based only on the graphical representation of the EoG problem. We then use our findings and study the problem of designing sparse SLAM problems that lead to reliable maximum likelihood estimates through the synthesis of sparse graphs with the maximum weighted tree connectivity. Characterizing graphs with the maximum number of spanning trees is an open problem in general. To tackle this problem, we establish several new theoretical results, including the monotone log-submodularity of the weighted number of spanning trees. We exploit these structures and design a complementary greedy–convex pair of efficient approximation algorithms with provable guarantees. The proposed synthesis framework is applied to various forms of the measurement selection problem in resource-constrained SLAM. Our algorithms and theoretical findings are validated using random graphs, existing and new synthetic SLAM benchmarks, and publicly available real pose-graph SLAM datasets.

Kim, H, Nerse, C, Lee, J & Wang, S 2019, 'Multidisciplinary Analysis and Multiobjective Design Optimization of a Switched Reluctance Motor for Improving Sound Quality', IEEE Access, vol. 7, pp. 66020-66027.
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In this study, the design optimization method for improving sound quality (SQ) of a switched reluctance motor (SRM) is proposed. The multidisciplinary finite element analysis (FEA) of an SRM is performed to evaluate both average torque and the SQ metrics to design the rotor configuration of the SRM. Specifically, the magneto-static FEA of the SRM is used to evaluate the average torque which is the most important performance of motors, and the local force distribution applied to the stator. Also, the transient structural FEA of the stator excited by the local force distribution, and the transient acoustic FEA are conducted to get the sound pressure radiated by the vibration of the stator. Then, the SQ metrics of loudness, sharpness, fluctuation strength and roughness can be obtained from the radiated sound pressure. We define the correlation function between the SQ metrics and the jury test results of the different types of SRMs. The weighted sum of the torque and the correlation function is set as an objective function. After that, design optimization method of the SRM using a design of experiments is discussed. This study does not consider the nonlinear material properties and is based on 2D analysis; however, with all these limitations, note that this is the first study to propose an overall procedure to increase the SQ of an SRM.

Kim, H-G, Nerse, C & Wang, S 2019, 'Topography optimization of an enclosure panel for low-frequency noise and vibration reduction using the equivalent radiated power approach', Materials & Design, vol. 183, pp. 108125-108125.
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An enclosure panel is widely used in industrial applications. The panel under a dynamic loading excites the surrounding air medium and noise is radiated into the acoustic space. The radiated sound can be suppressed by having changes in the structure. The noise reduction performance can be further improved by a design optimization. In this study, a topography optimization is conducted to design an enclosure panel. Topography optimization results in a bead pattern, which helps maintain the thickness at a constant level throughout the structure. The final optimized structure can be manufactured using a stamping process. Compared with other optimization methods, topography optimization requires minimal manufacturing effort and cost, with no additional increase in mass. Moreover, this type of optimization is effective for noise reduction problems because no holes are created in the structure. In this study, the objective function selected to minimize the low-frequency noise is the equivalent radiated power. The topography optimization of the enclosure panel has been conducted using the commercial software Altair OptiStruct, with loads and constraints considered. In order to verify the optimization result, in-situ experiment was performed with panels produced by the stamping process.

Kishore Kumar, D, Hsu, M-H, Ivaturi, A, Chen, B, Bennett, N & Upadhyaya, HM 2019, 'Optimizing room temperature binder free TiO ₂ paste for high efficiency flexible polymer dye sensitized solar cells', Flexible and Printed Electronics, vol. 4, no. 1, pp. 015007-015007.
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© 2019 IOP Publishing Ltd. Binder free TiO2 paste is prepared using tert-butyl alcohol in dilute acidic conditions at room temperature for flexible polymer dye sensitized solar cells (DSSCs). The present paper reports the detailed studies carried out to elucidate the importance of stirring times during the paste preparation on the final device performance. The maximum conversion efficiency of 4.2% was obtained for flexible DSSCs fabricated on tin doped indium oxide/polyethylene naphthalate substrates using TiO2 paste prepared with an optimum stirring time of 8 h. The effect of optimum stirring times on the device characteristics has been understood in terms of the detailed morphology and surface area measurements.

Kumar, C, Hejazian, M, From, C, Saha, SC, Sauret, E, Gu, Y & Nguyen, N-T 2019, 'Modeling of mass transfer enhancement in a magnetofluidic micromixer', Physics of Fluids, vol. 31, no. 6, pp. 063603-063603.
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The use of magnetism for various microfluidic functions such as separation, mixing, and pumping has been attracting great interest from the research community as this concept is simple, effective, and of low cost. Magnetic control avoids common problems of active microfluidic manipulation such as heat, surface charge, and high ionic concentration. The majority of past works on micromagnetofluidic devices were experimental, and a comprehensive numerical model to simulate the fundamental transport phenomena in these devices is still lacking. The present study aims to develop a numerical model to simulate transport phenomena in microfluidic devices with ferrofluid and fluorescent dye induced by a nonuniform magnetic field. The numerical results were validated by experimental data from our previous work, indicating a significant increase in mass transfer. The model shows a reasonable agreement with experimental data for the concentration distribution of both magnetic and nonmagnetic species. Magnetoconvective secondary flow enhances the transport of nonmagnetic fluorescent dye. A subsequent parametric analysis investigated the effect of the magnetic field strength and nanoparticle size on the mass transfer process. Mass transport of the fluorescent dye is enhanced with increasing field strength and size of magnetic particles.

Kumar, DK, Suazo-Davila, D, García-Torres, D, Cook, NP, Ivaturi, A, Hsu, M-H, Martí, AA, Cabrera, CR, Chen, B, Bennett, N & Upadhyaya, HM 2019, 'Low-temperature titania-graphene quantum dots paste for flexible dye-sensitised solar cell applications', Electrochimica Acta, vol. 305, pp. 278-284.
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© 2019 Graphene possesses excellent mechanical strength and chemical inertness with high intrinsic carrier mobility and superior flexibility making them exceptional candidates for optoelectronic applications. Graphene quantum dots (GQDs) derived from graphene domains have been widely explored to study their photoluminescence properties which can be tuned by size. GQDs are biocompatible, low cytotoxic, strongly luminescent and disperse well in polar and non-polar solvents showing bright promise for the integration into devices for bioimaging, light emitting and photovoltaic applications. In the present study, graphene quantum dots were synthesized by an electrochemical cyclic voltammetry technique using reduced graphene oxide (rGO). GQDs have been incorporated into binder free TiO 2 paste and studied as a photoelectrode material fabricated on ITO/PEN substrates for flexible dye sensitised solar cells (DSSCs). DSSC based on GQDs-TiO 2 exhibited open circuit output potential difference (V oc ) of 0.73 V, and short circuit current density (J sc ) of 11.54 mA cm −2 with an increment in power conversion efficiency by 5.48%, when compared with those with DSSC build with just a TiO 2 photoanode (open-circuit output potential difference (V oc ) of 0.68 V and short circuit density (J sc ) of 10.67 mA cm −2 ). The results have been understood in terms of increased charge extraction and reduced recombination losses upon GQDs incorporation.

Kumar, DK, Swami, SK, Dutta, V, Chen, B, Bennett, N & Upadhyaya, HM 2019, 'Scalable screen-printing manufacturing process for graphene oxide platinum free alternative counter electrodes in efficient dye sensitized solar cells', FlatChem, vol. 15, pp. 100105-100105.
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The graphene oxide paste (GO) was prepared by mixing α-terpineol and ethyl cellulose, and GO films was prepared by screen printing on fluorine doped Tin oxide (FTO) glass substrates to validate as an alternative counter electrode material to platinum in dye sensitized solar cells (DSSC). The graphene oxide films were characterised by X-Ray Diffraction, Scanning Electron Microscopy, Raman spectroscopy and the catalytic properties of films were being investigated by cyclic voltammetry and electrochemical Impedance measurements. The DSSC fabricated by coupling TiO 2 films soaked in N719 dye with GO as counter electrode exhibited photoconversion efficiency of 5.58% under standard one Sun illumination, whereas platinum based device showed photoconversion efficiency of 7.57%. The present study suggests that graphene oxide counter electrodes can be considered as a promising alternative to platinum, with further optimisation, which clearly has advantages in terms of its abundance and low cost processing towards industrial prospects.

Kuruneru, STW, Marechal, E, Deligant, M, Khelladi, S, Ravelet, F, Saha, SC, Sauret, E & Gu, Y 2019, 'A Comparative Study of Mixed Resolved–Unresolved CFD-DEM and Unresolved CFD-DEM Methods for the Solution of Particle-Laden Liquid Flows', Archives of Computational Methods in Engineering, vol. 26, no. 4, pp. 1239-1254.
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© 2018, CIMNE, Barcelona, Spain. The exorbitant economic and environmental cost associated with fouling propels the need to develop advanced numerical methods to accurately decipher the underlying phenomena of fouling and multiphase fluid transport in jet-engine fuel systems. Clogging of jet-fuel systems results in the foulants to settle in seconds to form a porous layer which restricts fuel flow. The objective of this research is to numerically examine the transient evolution of particle-laden liquid flow and particle accumulation on an idealized jet-fuel filter. This is achieved by using two numerical approaches: coupled unresolved computational fluid dynamics-discrete element method (CFD-DEM), and coupled mixed resolved–unresolved CFD-DEM method. We assess the efficacy of both numerical methods by comparing the numerical results against experimental data. Results have shown that the particle accumulation and deposition profiles are in good agreement with the experimental results. Moreover, it is found that the particle distribution spread along the length and height of the channel reflects the actual particle spread as observed in the experiments. The unresolved CFD-DEM and mixed resolved–resolved CFD-DEM method could be harnessed to study complex multiphase fluid flow transport in various other applications such as compact heat exchangers and fluidized beds.

Kuruneru, STW, Saha, SC, Sauret, E & Gu, YT 2019, 'Transient heat transfer and non-isothermal particle-laden gas flows through porous metal foams of differing structure', Applied Thermal Engineering, vol. 150, pp. 888-903.
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© 2019 Elsevier Ltd Multiphase solid-gas flows and particulate fouling in porous media are omnipresent in many environmental and industrial applications. However, the underlying mechanisms and transport behaviour of these complex fluids coupled with heat transfer effects are poorly understood. Moreover, the complexity of multiphase non-isothermal solid-gas transport is further compounded by the fact that thermal solid-gas transport through porous metal foams is not established. This paper numerically investigates non-isothermal solid-gas flows through an idealized metal foam heat exchanger based on a cylindrical ligament and a Weaire-Phelan model. We delve into the dynamics and heat transfer profiles of solid-gas flows immersed in porous metal foams based on various solid foulant properties. The foulant thermal behaviour based on various metal foam ligament wall temperatures is investigated. It is found that the foulant temperature profiles vary with time and the temperature profiles also vary with increasing wall temperature. Moreover, the Weaire-Phelan (WP) model can be used as an alternative to the real metal foam sample. The heat transfer between the foulant, wall, and fluid play a pivotal role in the alteration of the temperature profiles. The developed numerical methodology and the WP geometry may serve as a stepping-stone to address pertinent issues such as indoor environmental studies and optimization of compact heat exchangers.

Li, H, Luo, Z, Xiao, M, Gao, L & Gao, J 2019, 'A new multiscale topology optimization method for multiphase composite structures of frequency response with level sets', Computer Methods in Applied Mechanics and Engineering, vol. 356, pp. 116-144.
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© 2019 Elsevier B.V. This paper proposes a new multiscale topology optimization method for the concurrent design of multiphase composite structures under a certain range of excitation frequencies. Distinguished from the existed studies, a general concurrent design formulation for the dynamic composite structures with more than two material phases is developed. The macrostructureand its microstructures with multiple material phases are optimized simultaneously. The integral of the dynamic compliances over an interval of frequencies is formulated as the optimization objective, so as to minimize the frequency response within the concerned excitation range. The effective properties of the multiphase microstructures are evaluated by using the numerical homogenization method, which actually serves as a link to bridge the macro and micro finite element analyses. Furthermore, to describe the boundaries of multiple material phases for the microstructure, a parametric color level set method (PCLSM) is developed by using an efficient interpolation scheme. In this way, L level set functions can represent at most 2L material phases without any overlaps. Moreover, these “color” level sets are updated by directly using the well-established gradient-based algorithm, which can greatly facilitate the proposed method to solve the multi-material optimizations with multiple design constraints. Several 2D and 3D numerical examples are used to demonstrate the effectiveness of the proposed method in the concurrent design of the dynamic composite structures under the excitation frequency ranges.

Li, W, Huang, L & Ji, J 2019, 'Periodic solution and its stability of a delayed Beddington‐DeAngelis type predator‐prey system with discontinuous control strategy', Mathematical Methods in the Applied Sciences, vol. 42, no. 13, pp. 4498-4515.
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This paper investigates the periodic solution of a delayed Beddington‐DeAngelis (BD) type predator‐prey model with discontinuous control strategy. Firstly, the regularity and visibility analysis of the delayed predator‐prey model is carried out by using the principle of differential inclusion. Secondly, the positiveness and boundeness of the solution is discussed by employing the comparison theorem. Based on the boundary conditions of the model and the Mawhin‐like coincidence theorem, it is shown that the solution of the delayed BD system is asymptotically stable in finite time. Furthermore, it is found that there exists at least one periodic solution of the nonautonomous delayed predator‐prey model by using the principle of topological degree and set value mapping. Specially, when the nonautonomous delayed BD system degenerates into an autonomous system, some criteria are obtained to guarantee the convergence behavior of the harvesting solutions for the corresponding autonomous delayed BD system. Finally, numerical examples are given to demonstrate the applicability and effectiveness of main results. It is worthy to point out that the discontinuous control strategy is superior to the continuous harvesting policies adopted in existing literature.

Li, W, Jiang, C & Deng, M 2019, 'Thermal damage assessment of metallic plates using a nonlinear electromagnetic acoustic resonance technique', NDT & E International, vol. 108, pp. 102172-102172.
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Li, X, Zhao, S, Hu, W, Zhang, X, Pei, L & Wang, Z 2019, 'Robust superhydrophobic surface with excellent adhesive properties based on benzoxazine/epoxy/mesoporous SiO2', Applied Surface Science, vol. 481, pp. 374-378.
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Liao, H, Liao, C, Blamires, SJ & Tso, I 2019, 'Multifunctionality of an arthropod predator’s body coloration', Functional Ecology, vol. 33, no. 6, pp. 1067-1075.
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AbstractAnimal body colours can be shaped by many factors, including the need to attract mates, avoid predators and lure prey. In some contexts, these needs might compete. A number of studies have recently demonstrated that the silver, white, yellow or red bodies of spiders attract mates, lure prey or startle predators. Nevertheless, when spider bodies display different colours, little is known about the multifunctionality of the colours and whether they interact. The Australasian coin spider, Herrenia multipuncta, displays unconventional body coloration, with orange, black and grey regions across its body.We hypothesized that its coloration serves a multifunctional role, with the dorsal orange bands on its prosoma attracting prey and its orange ventrum deterring predators. We tested our hypothesis with field and laboratory experiments using dummies and real spiders, and modelling the visibility of the various colours to different predators and prey.Our field experiment showed significant prey attraction towards the orange‐grey dorsal pattern during the day and night, while our laboratory experiment showed that the lizard Japalura swinhonis stared at spiders and hesitated before attacking spiders when the orange abdominal region was uncovered. Our various visual models confirmed our experimental results by showing that the orange and grey body parts were always visible when contrasted against their natural backgrounds.Combined, our analyses provide evidence to conclude that the orange body colour of H. multipuncta is multifunctional, serving in both prey attraction and predator avoidance.A

Liu, L, Yu, J, Ji, J, Miao, Z & Zhou, J 2019, 'Cooperative adaptive consensus tracking for multiple nonholonomic mobile robots', International Journal of Systems Science, vol. 50, no. 8, pp. 1556-1567.
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© 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group. This paper addresses the cooperative adaptive consensus tracking for a group of multiple nonholonomic mobile robots, where the nonholonomic robot model is assumed to be a canonical vehicle having two actuated wheels and one passive wheel. By integrating a kinematic controller and a torque controller for the nonholonomic robotic system, a cooperative adaptive consensus tracking strategy is developed for the uncertain dynamic models using Lyapunov-like analysis in combination with backstepping approach and sliding mode technique. A key feature of the developed adaptive consensus tracking algorithm is the introduction of a directed network topology into the control constraints based on algebraic graph theory to characterise the communication interaction among robots, which plays an important role in realising the cooperative consensus tracking with respect to a specific common reference trajectory. Furthermore, a novel framework is proposed for developing a unified methodology for the convergence analysis of the closed-loop control systems, which can fully ensure the desired adaptive consensus tracking for multiple nonholonomic mobile robots. Subsequently, illustrative examples and numerical simulations are provided to demonstrate and visualise the theoretical results.

Liu, L, Zhang, T, Leighton, B, Zhao, L, Huang, S & Dissanayake, G 2019, 'Robust Global Structure From Motion Pipeline With Parallax on Manifold Bundle Adjustment and Initialization', IEEE Robotics and Automation Letters, vol. 4, no. 2, pp. 2164-2171.
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© 2016 IEEE. In this letter, we present a novel global structure from motion (SfM) pipeline that is particularly effective in dealing with low-parallax scenes and camera motion collinear with the features that represent the environment structure. It is therefore particularly suitable in Urban SLAM, in which frequent road-facing motion poses many challenges to conventional SLAM algorithms. Our pipeline includes a recently explored bundle adjustment (BA) method that exploits a feature parameterization using Parallax angle between on-Manifold observation rays (PMBA). It is demonstrated that this BA stage has a consistently stable optimization configuration for features with any parallax and therefore low-parallax features can stay in reconstruction without pre-filtering. To allow practical usage of PMBA, we provide a compatible initialization stage in the SfM to initialize all camera poses simultaneously, exhibiting friendliness to collinear motion. This is achieved by simplifying PMBA into a hybrid graph problem of high connectivity yet small node set size, solved using a robust linear programming technique. Using simulations and a series of publicly available real datasets including 'KITTI' and 'Bundle Adjustment in the Large,' we demonstrate the robustness of the position initialization stage in handling collinear motion and outlier matches, superior convergence performance of the BA stage in the presence of low-parallax features, and effectiveness of our pipeline to handle many sequential or out-of-order urban scenes.

Lu, S, Oberst, S, Zhang, G & Luo, Z 2019, 'Bifurcation analysis of dynamic pricing processes with nonlinear external reference effects', Communications in Nonlinear Science and Numerical Simulation, vol. 79, pp. 104929-104929.
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© 2019 Elsevier B.V. Dynamic pricing has been widely implemented to hedge against volatile demand. One challenging problem is the study of optimal price choices under the influence of this volatility. Stochastic demand is a prevalent assumption when it comes to model the volatility on pricing decisions. However, the demand volatility might also be produced by deterministic chaos, which has rarely been studied in this field of research to-date. We propose deterministic dynamic pricing processes that aim to maximise the revenue and to mimic a real pricing decision. Our model includes nonlinear consumer expectations that explain the effects of external information on consumers and discrete optimisations due to a non-smooth demand function that considers asymmetries in the perceptions of gains or losses of consumers and finite price choices of companies. Volatile markets can show up because of non-periodic consumer expectations, period adding bifurcations, codimension-2 points and coexisting solutions. Results highlight that optimal pricing strategies should agree with the dynamics of consumer expectations. Disregarding deterministic dynamics may not only cause revenue losses in practice but might also mislead regulators about the underlying mechanisms that consumers and companies respond to. We introduce for the first time an irregular pricing strategy: a company can make the first return iteration of each sales price non-periodic to follow non-periodic consumer expectations when having finite price choices. These results may justify implementing irregular pricing strategies in the case of practical pricing decisions. Here, the existence of coexisting solutions can assist to identify potential market manipulations within a monopoly market. This not only contributes to a fresh look on volatile markets but also emphasises the importance of initial conditions to pricing decisions and price regulations.

Lu, W & Liu, D 2019, 'A Scalable Sampling-Based Optimal Path Planning Approach via Search Space Reduction', IEEE Access, vol. 7, pp. 153921-153935.
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© 2013 IEEE. Many sampling strategies in Sampling-Based Planning (SBP) often consider goal and obstacle population and may however become less efficient in large and cluttered 3D environments with a goal distanced away. This paper presents a search-space-Reduced optimal SBP approach (RSBP) for a rigid body. This reduced space is found by a sparse search tree, which is enabled by a Metric Function (MF) built on a neural network. The offline-learnt MF estimates the minimum traveling cost between any two nodes in a fixed small workspace with various obstacles. It allows connections of two sparse nodes without path planning, where the connections represent the traveling costs (not paths). It is proven that the asymptotic optimality is preserved in the RSBP (assuming a zero-error MF) and the optimality degeneration is bounded (assuming a bounded-error MF). The computational complexity during planning is shown linear to the Lebesgue measure of the entire search space (assuming the same sampling density across environments). Numerical simulations have shown that in tested large and cluttered environments the RSBP is at least as fast as the bidirectional fast marching tree∗ and informed rapidly exploring random tree∗, with planned paths of similar optimality. The results also have shown the RSBP's improved scalability to large environments and enhanced efficiency in dealing with narrow passages.

Mazarov, J, Wolf, P, Schallow, J, Nöhring, F, Deuse, J & Richter, R 2019, 'Industrial Data Science in Wertschöpfungsnetzwerken', Zeitschrift für wirtschaftlichen Fabrikbetrieb, vol. 114, no. 12, pp. 874-877.
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Kurzfassung Industrial Data Science eröffnet produzierenden Unternehmen innovative Möglichkeiten zur Optimierung von Produkten und Prozessen sowie der Initiierung neuer Geschäftsmodelle in Wertschöpfungsnetzwerken. Um Unternehmen zum zielgerichteten Einsatz moderner Analysetechnologien zu befähigen, werden in diesem Beitrag das Konzept eines integrierten, datengetriebenen Referenzbaukastens zur industriellen Datenanalyse sowie dessen Realisierung als kollaborative Service-Plattform vorgestellt und beispielhaft Anwendungsfälle skizziert.

Melnikov, A, Chiang, YK, Quan, L, Oberst, S, Alù, A, Marburg, S & Powell, D 2019, 'Acoustic meta-atom with experimentally verified maximum Willis coupling', Nature Communications, vol. 10, no. 1, pp. 3148-3148.
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AbstractAcoustic metamaterials are structures with exotic acoustic properties, with promising applications in acoustic beam steering, focusing, impedance matching, absorption and isolation. Recent work has shown that the efficiency of many acoustic metamaterials can be enhanced by controlling an additional parameter known as Willis coupling, which is analogous to bianisotropy in electromagnetic metamaterials. The magnitude of Willis coupling in a passive acoustic meta-atom has been shown theoretically to have an upper limit, however the feasibility of reaching this limit has not been experimentally investigated. Here we introduce a meta-atom with Willis coupling which closely approaches this theoretical limit, that is much simpler and less prone to thermo-viscous losses than previously reported structures. We perform two-dimensional experiments to measure the strong Willis coupling, supported by numerical calculations. Our meta-atom geometry is readily modeled analytically, enabling the strength of Willis coupling and its peak frequency to be easily controlled.

Miao, Z, Yu, J, Ji, J & Zhou, J 2019, 'Multi-objective region reaching control for a swarm of robots', Automatica, vol. 103, no. IEEE Transaction Robotics and Automation 14 6 1998, pp. 81-87.
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© 2019 Elsevier Ltd This paper is concerned with the multi-objective region reaching control for a swarm of robots which are formulated by Lagrangian dynamics. Two distributed multi-objective region reaching control protocols are proposed for the networked robotic systems under directed acyclic topology, and a unifying methodology is presented to perform the convergence analysis for the robotic systems with static and moving target regions. The control strategy is developed by using the potential energy function approach, and the specified shapes of the various desired regions are constructed by selecting appropriate objective functions. In this control strategy, a network of a large number of robots evolves into multiple groups, and the robots in each group only require communicating with their neighbors. Thus, the proposed control strategy is effective for multi-objective region reaching control for a swarm of robots in practical applications. Finally, simulation examples are given to show the validity of the theoretical results.

Moore, SI, Ruppert, MG & Yong, YK 2019, 'An optimization framework for the design of piezoelectric AFM cantilevers', Precision Engineering, vol. 60, pp. 130-142.
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Moore, SI, Ruppert, MG, Harcombe, DM, Fleming, AJ & Yong, YK 2019, 'Design and Analysis of Low-Distortion Demodulators for Modulated Sensors', IEEE/ASME Transactions on Mechatronics, vol. 24, no. 4, pp. 1861-1870.
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Nerse, C & Wang, S 2019, 'On the formation of complex modes in non-proportionally damped systems', Journal of Sound and Vibration, vol. 463, pp. 114978-114978.
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In the classical studies of non-proportionally damped systems, the resulting complex modal parameters are obtained by solving the generalized eigenvalue problem. In the present study, we propose a unique method to obtain complex modes for discrete and continuous systems. Based on a wave analogy, the difference between a complex mode and a real normal mode is represented by the summation of patterns that propagate from the boundaries. Owing to the spatial non-proportionality of the damping, these patterns undergo changes at a damping intersection. The governing equation for this phenomenon is expressed by Snell's law. We show that, in a similar manner to the refractive index for the medium in which light waves travel, a damping field index can be conceived for individual damping regions, such that they may be scaled against the damping field index of the undamped region, which is assumed to be unity. However, unlike the refractive index, we show that the damping field index is dependent on the spatial distribution of damping. The procedure for obtaining the complex modes is illustrated based on a plate structure with simply supported boundary conditions. The practical applications of the proposed approach and its limitations are discussed based on numerical examples.

Nguyen, K-D & Liu, D 2019, 'Gibbon-inspired Robust Asymmetric Brachiation along an Upward Slope', International Journal of Control, Automation and Systems, vol. 17, no. 10, pp. 2647-2654.
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© 2019, ICROS, KIEE and Springer. This paper investigates the robust control of an underactuated brachiating robot. The control schemes are motivated by the applications that require robots to move through lattice structures, such as the inspection and maintenance of power transmission lines and towers. Inspired by the pendulum-like movements that enable gibbons' arboreal locomotion, the controllers are designed to synchronize the brachiator with a virtual oscillator. Two controllers are proposed: a model-dependent feedback linearization scheme and a sliding-mode scheme that is independent of the system model. These controllers are tasked to drive a robotic brachiator in two cases with different geometries: symmetric geometry, where its links have equal lengths, and asymmetric geometry, where its links have different lengths. The numerical results illustrate that the proposed schemes are robust to the arbitrary initial conditions of the brachiator, the motor torque limitation at the elbow joint, as well as the geometry of the brachiator. Furthermore, they are able to perform successful fast swing-up and dynamic brachiating along a structural member with an upward slope in a unified control framework for both symmetric and asymmetric geometries.

Nguyen, LTN, Eager, D & Nguyen, H 2019, 'The relationship between compression garments and electrocardiogram signals during exercise and recovery phase', BioMedical Engineering OnLine, vol. 18, no. 1, pp. 27-27.
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© 2019 The Author(s). Background: The direction of the current research was to investigate whether electrocardiogram (ECG) signals have been impacted by using compression garments during exercise and recovery phase. Each subject is non-athletes, conducted two running tests, wearing either non-compression garments (NCGs) or compression garments (CGs) throughout experiments and 2-h of the recovery phase. Experiment 1 (number of participants (n) = 8; 61.4 ± 13.7 kg, 25.1 ± 3.8 years, 165.9 ± 8.3 cm) focused on the exercising phase while Experiment 2 (n = 14; 60.9 ± 12.0 kg, 24.7 ± 4.5 years, 166.0 ± 7.6 cm) concentrated on the recovery phase. Electrocardiogram (ECG) data were collected through wearable biosensors. Results: The results demonstrated a significant difference between compression garments and non-compression garments at the end of the tests and from 90 min onwards during the recovery phase (p < 0.05). Corrected QT (QTc), ST interval and heart rate (HR) indicated the significant difference between NCGs and CGs. Conclusion: Based on the findings, the utilization of compression garments showed a positive influence in non-athletes based on the quicker recovery in HR, ST, and QTc.

Oberst, S, Lenz, M, Lai, JCS & Evans, TA 2019, 'Termites manipulate moisture content of wood to maximize foraging resources', Biology Letters, vol. 15, no. 7, pp. 20190365-20190365.
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Animals use cues to find their food, in microhabitats within their physiological tolerances. Termites build and modify their microhabitat, to transform hostile environments into benign ones, which raises questions about the relative importance of cues. Termites are desiccation intolerant and foraging termites are attracted to water, so most research has considered moisture to be a cue. However, termites can also transport water to food, and so moisture may play other roles than previously considered. To examine the role of moisture, we compared Coptotermes acinaciformis termite foraging decisions in laboratory experiments when they were offered dry and moist wood, with and without load. Without load, termites preferred moist wood and ate it without any building, whereas they moistened dry wood after wrapping it in a layer of clay. For the ‘With load’ units, termites substituted some of the wood for load-bearing clay walls, and kept the wood drier than on the unloaded units. As drier wood has higher compressive strength and higher rigidity, it allows more of the wood to be consumed. These results suggest that moisture plays a more important role in termite ecology than previously thought. Termites manipulate the moisture content according to the situational context and use it for multiple purposes: increased moisture levels soften the fibre, which facilitates foraging, yet keeping the wood dry provides higher structural stability against buckling which is especially important when foraging on wood under load.

Peng, J, Liu, D, Parnell, J & Kessissoglou, N 2019, 'Influence of translational vehicle dynamics on heavy vehicle noise emission', Science of The Total Environment, vol. 689, pp. 1358-1369.
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Vehicle dynamics can play a significant role in the noise emission from heavy vehicles. In this work, a heavy vehicle noise emission model is presented to study the influence of translational vehicle dynamics on the sound power level emitted by heavy-duty trucks. Vehicle speed and acceleration are calculated using an analytical approximation that describes the tractive and retarding forces acting on a heavy vehicle on grade. Heavy vehicle noise emission associated with rolling noise is defined with reference to the Nordic traffic noise model that takes into account the number of axles for different articulated trucks. An expression for engine noise emission in terms of vehicle speed, weight, engine power, aerodynamic properties and road grade is derived. The individual and combined effects of engine noise and rolling noise for different vehicle mass combinations are examined. The influence of road grade on vehicle kinematics and noise emission is also investigated.

Peng, J, Parnell, J & Kessissoglou, N 2019, 'A six-category heavy vehicle noise emission model in free-flowing condition', Applied Acoustics, vol. 143, pp. 211-221.
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Annoyance and sleep disturbance caused by transportation noise are frequently associated with heavy vehicles. The ability to accurately predict heavy vehicle noise impact using conventional road traffic noise prediction methods has reduced over the years as the variety of heavy vehicles have increased progressively and the predominant long haul freight vehicle is trending towards larger trucks with a greater number of axles. In this paper, a six-category heavy vehicle source emission model in free-flowing condition has been developed based on the state-wide road setting in New South Wales, Australia. The six-category model allows traffic noise across the road network, carrying a diverse fleet of heavy vehicles, to be predicted with notably higher accuracy and precision in comparison to conventional models that aggregate heavy vehicles into one, or at most, two distinct categories. A comparative analysis is carried out to examine the source emission from various traffic mix scenarios in urban areas and along major freight routes. Current findings also highlight the importance of distinguishing regional characteristics in a harmonised road traffic noise prediction model.

Robone, A, Kuruneru, STW, Islam, MS & Saha, SC 2019, 'A macroscopic particle modelling approach for non-isothermal solid-gas and solid-liquid flows through porous media', Applied Thermal Engineering, vol. 162, pp. 114232-114232.
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The complexity of multiphase flows in many engineering systems such as heat exchangers signify the need to develop new and advanced numerical models to analyse the interactions the working fluid and unwanted solid foulants. Fouling is present in a myriad of industrial and domestic processes and it has a negative impact on the economy and the environment. The mechanisms that govern non-isothermal solid-fluid flow through porous metal foam heat exchangers are complex and poorly understood. In this research, a coupled finite volume method (FVM) and macroscopic particle model (MPM) is developed and implemented in ANSYS Fluent to examine the transient evolution of a non-isothermal multiphase solid-fluid flow and the interaction between coupled interactions of solid particles, fluid, and porous media. The maximum particle temperature is dependent on the fluid and solid particle thermo-physical properties in addition to the temperature of the cylindrical ligaments of the porous media. The present results show that the smallest solid particles reach the highest temperatures in the porous heat exchanger and at low inlet velocities, the highest particle temperatures are realized. The results pertaining to maximum particle temperatures are prevalent in many industrial processes and acquiring knowledge of the maximum particle temperature serves as a steppingstone for comprehending complex multiphase solid-fluid flows such as the cohesiveness between the particles and the particle adhesion with the walls. The results of these studies could potentially be used in the future to optimize metal foam heat exchanger designs.

Ruppert, MG 2019, '2018 IEEE Transactions on Control Systems Technology Outstanding Paper Award', IEEE Transactions on Control Systems Technology, vol. 27, no. 2, pp. 463-463.
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Ruppert, MG, Moore, SI, Zawierta, M, Fleming, AJ, Putrino, G & Yong, YK 2019, 'Multimodal atomic force microscopy with optimized higher eigenmode sensitivity using on-chip piezoelectric actuation and sensing', Nanotechnology, vol. 30, no. 8, pp. 085503-085503.
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Schleppi, J, Gibbons, J, Groetsch, A, Buckman, J, Cowley, A & Bennett, N 2019, 'Manufacture of glass and mirrors from lunar regolith simulant', Journal of Materials Science, vol. 54, no. 5, pp. 3726-3747.
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© 2018, The Author(s). Future planetary surface missions to the Moon or Mars, for example, can be augmented by the use of local materials, in order to reduce launch mass and expand mission capability. Using lunar regolith simulant and heating it within a susceptor-assisted microwave oven, it was possible to manufacture a variety of basaltic glasses. Furthermore, it was possible to shape these glasses by grinding and polishing the surface flat and smooth. Glasses manufactured from different lunar regolith simulants were coated with aluminium or silver, and the reflective properties of the resulting mirrors and uncoated surfaces were measured. It was shown that with a porous and/or smooth surface finish, mirrors could be made that reflect the incident solar light (400 nm–1250 nm) in-between 30% for the worst and 85% for the best samples. The same samples with uncoated surfaces showed to reflect less than 7% of incident solar light in the same wavelength range.

Seckelmann, T, Barthelmey, A, Kaiser, M & Deuse, J 2019, 'Simulationsgestützte arbeitswissenschaftliche Bewertung von MRK-Arbeitsplätzen', Zeitschrift für wirtschaftlichen Fabrikbetrieb, vol. 114, no. 11, pp. 744-748.
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Kurzfassung Um während der Planung eines MRK-Systems das beste Lösungsszenario auszuwählen, ist eine arbeitswissenschaftliche Bewertung erforderlich. Wirtschaftlichkeit, Ergonomie, Sicherheit sowie die organisatorischen Auswirkungen sind dabei die wichtigsten Bewertungskriterien. Innerhalb des Beitrags werden die Entwicklung eines auf diesen Kriterien basierten Bewertungsverfahrens und dessen Integration in ein Simulationswerkzeug sowie die Validierung anhand eines industriellen Anwendungsfalls dargestellt.

Sepehrirahnama, S, Ong, ET, Lee, HP & Lim, K-M 2019, 'Fast computation for vibration study of partially submerged structures using low resolution hydrodynamic model', Journal of Fluids and Structures, vol. 91, pp. 102756-102756.
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Sepehrirahnama, S, Xu, D, Ong, ET, Lee, HP & Lim, K-M 2019, 'Fluid–Structure Interaction Effects on Free Vibration of Containerships', Journal of Offshore Mechanics and Arctic Engineering, vol. 141, no. 6.
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The interaction between fluid and structure affects the vibration response of the structure due to the additional hydrodynamic pressure. These effects are accounted for by incorporating the so-called added mass into the vibration equation of the structure. In this paper, a containership was used to study the impact of the added mass on its free vibration response. The natural frequencies of the ship decrease after including the added mass in the vibration analysis. It is shown that the frequency-ascending sequence of the wet mode shapes, for which the added mass is accounted for, may differ from that obtained for the dry state of the ship. Also, the effects of different draft levels on the mode shapes of the ship are reported. These results provide a better insight for designing ships based on their wet-state frequencies and mode shapes, which is the typical operation condition when sailing in the open seas.

Shakor, P, Nejadi, S & Paul, G 2019, 'A Study into the Effect of Different Nozzles Shapes and Fibre-Reinforcement in 3D Printed Mortar', Materials, vol. 12, no. 10, pp. 1708-1708.
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Recently, 3D printing has become one of the most popular additive manufacturing technologies. This technology has been utilised to prototype trial and produced components for various applications, such as fashion, food, automotive, medical, and construction. In recent years, automation also has become increasingly prevalent in the construction field. Extrusion printing is the most successful method to print cementitious materials, but it still faces significant challenges, such as pumpability of materials, buildability, consistency in the materials, flowability, and workability. This paper investigates the properties of 3D printed fibre-reinforced cementitious mortar prisms and members in conjunction with automation to achieve the optimum mechanical strength of printed mortar and to obtain suitable flowability and consistent workability for the mixed cementitious mortar during the printing process. This study also considered the necessary trial tests, which are required to check the mechanical properties and behaviour of the proportions of the cementitious mix. Mechanical strength was measured and shown to increase when the samples were printed using fibre-reinforced mortar by means of a caulking gun, compared with the samples that were printed using the same mix delivered by a progressive cavity pump to a 6 degree-of-freedom robot. The flexural strength of the four-printed layer fibre-reinforced mortar was found to be 3.44 ± 0.11 MPa and 5.78 ± 0.02 MPa for the one-layer. Moreover, the mortar with different types of nozzles by means of caulking is printed and compared. Several experimental tests for the fresh state of the mortar were conducted and are discussed.

Shakor, P, Nejadi, S, Paul, G & Malek, S 2019, 'Review of Emerging Additive Manufacturing Technologies in 3D Printing of Cementitious Materials in the Construction Industry', Frontiers in Built Environment, vol. 4, pp. 1-17.
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Additive manufacturing is a fabrication technology that is rapidly revolutionizing the manufacturing and construction sectors. In this paper, a review of various prototyping technologies for printing cementitious materials and selected 3D printing techniques are presented in detail. Benchmark examples are provided to compare three well-known printing techniques; inkjet printing (binder jetting), selected laser sintering (SLS), and extrusion printing (extrusion based process). A comprehensive search in the literature was conducted to identify various mix designs that could be employed when printing cementitious materials. Aspects of concrete mix design are described, and some new experiments are conducted to analyse the printability of new mixes by the authors. Future research in the area of the rheology of cementitious materials and its relationship with the structural performance of finished concretes are highlighted.

Shakor, P, Nejadi, S, Paul, G, Sanjayan, J & Aslani, F 2019, 'Heat curing as a means of postprocessing influence on 3D printed mortar specimens in powderbased 3D printing', Indian Concrete Journal, vol. 93, no. 9, pp. 65-74.
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Inkjet (Powder-based) three-dimensional printing (3DP) shows significant promise in concrete construction applications. The accuracy, speed, and capacity to build complicated geometries are the most beneficial features of inkjet 3DP. Therefore, inkjet 3DP needs to be carefully studied and evaluated with construction goals in mind and employed in real-world applications, where it is most appropriate. This paper focuses on the important aspect of curing 3DP specimens. It discusses the enhanced mechanical properties of the mortar that are unlocked through a heat-curing process. Experiments were conducted on cubic mortar specimens that were printed and cured in an oven at a range of different temperatures (40, 60, 80, 90, 100°C). The results of the experimental tests showed that 80°C is the optimum heat-curing temperature to achieve the highest compressive strength and flexural strength of the printed mortar specimens. These tests were performed on two different dimensions of the cubic specimens, namely, 20x20x20 mm, 50x50x50 mm and on prism specimens with dimensions of 160x40x40 mm. The inkjet 3DP process and the post-processing curing are discussed. In addition, 3D scanning of the printed specimens was employed and the surface roughness profiles of the 3DP gypsum specimens and cement mortar are recorded 13.76 µm and 22.31 µm, respectively.

Shakor, P, Nejadi, S, Paul, G, Sanjayan, J & Nazari, A 2019, 'Mechanical Properties of Cement-Based Materials and Effect of Elevated Temperature on 3-D Printed Mortar Specimens in Inkjet 3-D Printing', ACI Materials Journal, vol. 116, no. 2, pp. 55-67.
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Copyright © 2019, American Concrete Institute. All rights reserved. Three-dimensional (3-D) printers have the potential to print samples that can be used as a scaffold for a variety of applications in different industries. In this paper, cement-based materials including ordinary portland cement, calcium aluminate cement (passing 150 µm [0.0059 in.] size sieve), and fine sand were investigated as the cement-based materials in inkjet 3-D printing. Prism specimens were printed for the three-point bending test; and cubic specimens were printed for the uniaxial compressive strength test. Prism samples were printed along different directional axes (X, Y, and Z). The tests were conducted at different saturation levels (water-cement ratio [w/c]) as represented by S100C200, S125C250, S150C300, and S170C340. The prism specimens were cured in water for 7 and 28 days while cubic specimens were cured in Ca(OH) 2 and water for 7 and 28 days at the same ambient temperatures. In general, the results changed according to the directional axes of the prisms. However, following water curing, the cubic samples were heated up to 40°C (104°F) in an oven and a higher compressive strength was evident compared to the samples which were only cured in the room-temperature water. The wettability test for both powders has been conducted in the presented study.

Sick, N, Preschitschek, N, Leker, J & Bröring, S 2019, 'A new framework to assess industry convergence in high technology environments', Technovation, vol. 84-85, pp. 48-58.
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© 2018 Elsevier Ltd The process of convergence, from science and technology convergence to that of markets as well as entire industries can be witnessed in a range of different high technology environments such as IT and NanoBiotech. Although this phenomenon has been subject of analysis in an increasing number of studies, the notion of industry convergence – the final step of a full convergence process - still lacks a common definition. The missing conceptual definition of what industry convergence really is and how it can be assessed impedes both analyses and monitoring - let alone its anticipation. To address the missing conceptual definition of the final step in convergence, this paper seeks to develop a framework based on novel indicators that enable identifying and monitoring trends of industry convergence in high technology environments. Building on indicators in the domain of collaboration, a framework, which distinguishes different stages and types of industry convergence is developed. Subsequently, the newly developed framework is empirically illustrated in the area of stationary energy storage based on publicly available data. To this end, the full text database Nexis is used to conduct a search in news reports on collaborations in the domain of stationary energy storage. The study contributes to the growing body of convergence literature by providing a novel framework allowing the identification of not only industry convergence as the final step of the convergence process but also the classification of its type. Practical implications include an orientation for companies in converging environments on when and how to close the resulting technology and market competence gaps.

Singh, M, Hossain, A & Wei, DB 2019, 'A Hybrid Model for Studying the Size Effects on Flow Stress in Micro-Forming with the Consideration of Grain Hardening', Key Engineering Materials, vol. 794, pp. 97-104.
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Size effects extremely exist in the metal micro-forming process. When a deformation process scales down to micro scale, the appearances of geometry size and single grain size start to play a major role in deformation. Generally, the size effects are unavoidable in the experimental work and cannot be neglect in the optimization of micro-forming processes. In this paper, size effect on flow stress is investigated in the form of the coupled effect of workpiece geometry (sample thickness) and grain size, (T/D) by the micro tensile test of pure copper foil. Following the previous approaches, a new hybrid material model is projected to describe the hardening behavior of grains in polycrystalline material. Tensile tests performed on the copper foil with constant thickness and width, while to get dissimilar grain sizes, the foil annealed for different times. The ratio of thickness to grain size (T/D) is limited to larger than 1 (T/D˃1). A hybrid material model is proposed and established based on grain heterogeneity and sample thickness. The hybrid material model builds a relationship between the surface layer and sheet interior. The hybrid material model developed by the strain gradient theory in which the dislocation cell structure, cell densities (interior and wall) engaged to define the polycrystalline aggregate and calculated the dislocations in a grain (grain interior and grain wall). The results show that flow stress varies with the different values of T/D, but with an increase of the share of the grains flow stress start to decreases. After applying the hybrid material model of flow stress, the micro-tensile test of copper foil is simulated by finite element method. The simulation outcomes well matched with experimental results.

Smith, AJ, Best, G, Yu, J & Hollinger, GA 2019, 'Real-time distributed non-myopic task selection for heterogeneous robotic teams', Autonomous Robots, vol. 43, no. 3, pp. 789-811.
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Song, R, Clemon, L & Telenko, C 2019, 'Uncertainty and Variability of Energy and Material Use by Fused Deposition Modeling Printers in Makerspaces', Journal of Industrial Ecology, vol. 23, no. 3, pp. 699-708.
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© 2018, Yale University. Desktop-grade fused deposition modeling (FDM) printers are popular because of compact sizes and affordable prices. If we are moving toward a future where desktop FDM printers are in every school and office, like conventional printers, then these machines will consume a large amount of energy and material. However, it is very difficult to evaluate the environmental impacts of FDM printers since there are so many different brands and types of printers using different raw materials under different scenarios. This study uses data from two different printing sites to evaluate the scenario and parameter uncertainty and variability in energy and material balances for FDM printers. Data from the two makerspaces provide insight into the material and energy consumption data using polylactic acid and acrylonitrile butadiene styrene (ABS) with four types of printers. The use of actual performance data allowed for the additional study of scrap ratio. Regressions provide insight into predictive factors for energy and material consumption. Monte Carlo simulations show the range of energy life cycle inventory values for the desktop-grade FDM printers. From the regressions, Type A Pro was the most energy-intensive machine. For material waste, an open-access makerspace using ABS was associated with higher scrap ratio. Regression analysis indicates that the rate of material usage is not a strong predictor of waste rates. The amount of waste generated across both sites indicates that more ubiquitous access to FDM printing may create a significant addition to the waste stream.

Stender, M, Oberst, S & Hoffmann, N 2019, 'Recovery of Differential Equations from Impulse Response Time Series Data for Model Identification and Feature Extraction', Vibration, vol. 2, no. 1, pp. 25-46.
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Time recordings of impulse-type oscillation responses are short and highly transient. These characteristics may complicate the usage of classical spectral signal processing techniques for (a) describing the dynamics and (b) deriving discriminative features from the data. However, common model identification and validation techniques mostly rely on steady-state recordings, characteristic spectral properties and non-transient behavior. In this work, a recent method, which allows reconstructing differential equations from time series data, is extended for higher degrees of automation. With special focus on short and strongly damped oscillations, an optimization procedure is proposed that fine-tunes the reconstructed dynamical models with respect to model simplicity and error reduction. This framework is analyzed with particular focus on the amount of information available to the reconstruction, noise contamination and nonlinearities contained in the time series input. Using the example of a mechanical oscillator, we illustrate how the optimized reconstruction method can be used to identify a suitable model and how to extract features from uni-variate and multivariate time series recordings in an engineering-compliant environment. Moreover, the determined minimal models allow for identifying the qualitative nature of the underlying dynamical systems as well as testing for the degree and strength of nonlinearity. The reconstructed differential equations would then be potentially available for classical numerical studies, such as bifurcation analysis. These results represent a physically interpretable enhancement of data-driven modeling approaches in structural dynamics.

Stender, M, Oberst, S, Tiedemann, M & Hoffmann, N 2019, 'Complex machine dynamics: systematic recurrence quantification analysis of disk brake vibration data', Nonlinear Dynamics, vol. 97, no. 4, pp. 2483-2497.
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Complex machine dynamics, as caused by friction-induced vibrations and related to brake squeal, have gained significant attention in research and industry for decades. Today, remedies heavily rely on experimental testing due to the low prediction quality of numerical models. However, there is considerable lack of in-depth studies in characterizing self-excited oscillations encoded in scalar measurements. We complement previous works on phase-space reconstruction and recurrence plots analysis to a larger data base by applying a novel systematic approach using a large data base. This framework considers appropriate delay embedding, time series partitioning into squealing and non-squealing parts and comparison to operational parameters of the brake system. By means of recurrence plot analysis, we illustrate that friction-excited vibrations are multi-scale in nature. Results confirm the existence of low-dimensional attractors in squealing regimes with increasing values of determinism and periodicity with rising vibration levels. It is shown that the squeal propensity can be directly linked to recurrence quantification measures. Using determinism and the clustering coefficient as metrics, we show for the first time that is possible to predict instabilities in regions of non-squealing conditions.

Tang, L, Wang, Y, Ding, X, Yin, H, Xiong, R & Huang, S 2019, 'Topological local-metric framework for mobile robots navigation: a long term perspective', Autonomous Robots, vol. 43, no. 1, pp. 197-211.
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© 2018, Springer Science+Business Media, LLC, part of Springer Nature. Long term mapping and localization are the primary components for mobile robots in real world application deployment, of which the crucial challenge is the robustness and stability. In this paper, we introduce a topological local-metric framework (TLF), aiming at dealing with environmental changes, erroneous measurements and achieving constant complexity. TLF organizes the sensor data collected by the robot in a topological graph, of which the geometry is only encoded in the edge, i.e. the relative poses between adjacent nodes, relaxing the global consistency to local consistency. Therefore the TLF is more robust to unavoidable erroneous measurements from sensor information matching since the error is constrained in the local. Based on TLF, as there is no global coordinate, we further propose the localization and navigation algorithms by switching across multiple local metric coordinates. Besides, a lifelong memorizing mechanism is presented to memorize the environmental changes in the TLF with constant complexity, as no global optimization is required. In experiments, the framework and algorithms are evaluated on 21-session data collected by stereo cameras, which are sensitive to illumination, and compared with the state-of-art global consistent framework. The results demonstrate that TLF can achieve similar localization accuracy with that from global consistent framework, but brings higher robustness with lower cost. The localization performance can also be improved from sessions because of the memorizing mechanism. Finally, equipped with TLF, the robot navigates itself in a 1 km session autonomously.

Thürer, M, Maschek, T, Fredendall, L, Gianiodis, P, Stevenson, M & Deuse, J 2019, 'On the integration of manufacturing strategy: deconstructing Hoshin Kanri', Management Research Review, vol. 42, no. 3, pp. 412-426.
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PurposeThe purpose of this paper is to show that Hoshin Kanri has the potential to integrate the operations strategy literature into a coherent structure. Hoshin Kanri’s planning process is typically described as a top-down cascading of goals, starting with the senior management’s goals and moving to the lowest organizational level. The authors argue that this misrepresents a firm’s actual cognitive processes in practice because it implies reasoning from the effects to the cause, and assumes a direct causal relationship between what the customer wants and what is realizable by the system.Design/methodology/approachThis study is conceptual, based on abductive reasoning and the literature.FindingsThe actual strategic thought process executed in an organization consists of three iterative processes: (i) a translation process that derives the desired customer attributes from customer/stakeholder data, (ii) a process of causal inference that predicts realizable customer attributes from a possible system design and (iii) an integrative process of strategic choices whereby (i) and (ii) are aligned. Each element relies on different cognitive processes (logical relation, causal relation and choice).Research limitations/implicationsBy aligning the thought and planning processes, the competing concepts of manufacturing strategy are integrated into a coherent structure.Practical implicationsDifferent techniques have to be applied for each of the three elements. As each element relies on...

Viera, C, Garcia, LF, Lacava, M, Fang, J, Wang, X, Kasumovic, MM & Blamires, SJ 2019, 'Silk physico-chemical variability and mechanical robustness facilitates intercontinental invasibility of a spider', Scientific Reports, vol. 9, no. 1.
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AbstractThere are substantive problems associated with invasive species, including threats to endemic organisms and biodiversity. Understanding the mechanisms driving invasions is thus critical. Variable extended phenotypes may enable animals to invade into novel environments. We explored here the proposition that silk variability is a facilitator of invasive success for the highly invasive Australian house spider, Badumna longinqua. We compared the physico-chemical and mechanical properties and underlying gene expressions of its major ampullate (MA) silk between a native Sydney population and an invasive counterpart from Montevideo, Uruguay. We found that while differential gene expressions might explain the differences in silk amino acid compositions and protein nanostructures, we did not find any significant differences in silk mechanical properties across the populations. Our results accordingly suggest that B. longinqua’s silk remains functionally robust despite underlying physico-chemical and genetic variability as the spider expands its range across continents. They also imply that a combination of silk physico-chemical plasticity combined with mechanical robustness might contribute more broadly to spider invasibilities.

Wang, G, Ji, J & Zhou, J 2019, 'Practical stochastic synchronisation of coupled harmonic oscillators subjected to heterogeneous noises and its applications to electrical systems', IET Control Theory & Applications, vol. 13, no. 1, pp. 96-105.
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© The Institution of Engineering and Technology 2018. This study focuses on the practical stochastic synchronisation of coupled harmonic oscillators subjected to heterogeneous noises, where the dissipative and restorative couplings are no longer required in the connected network topologies. By employing the variational approach in combination with Lyapunov-like analysis, some simple yet generic practical synchronisation criteria are established in the sense of probability distribution and of mean square for coupled harmonic oscillator with directed network topology. Three main issues on stochastic synchronisation, including practical distribution synchronisation, stochastic distribution synchronisation, and practical mean square synchronisation, as well as their differences and relationships are fully addressed. The developed practical synchronisation criteria are then applied to a representative model of electrical systems which are composed of LC oscillators with linear time-invariant (LTI) resistors and inductors. Finally, numerical simulations are provided to show the effectiveness of the developed methods.

Wang, J, Song, J, Zhao, L, Huang, S & Xiong, R 2019, 'A submap joining algorithm for 3D reconstruction using an RGB-D camera based on point and plane features', Robotics and Autonomous Systems, vol. 118, pp. 93-111.
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© 2019 Elsevier B.V. In standard point-based methods, the depth measurements of the point features suffer from noise, which will lead to incorrect global structure of the environment. This paper presents a submap joining based SLAM with an RGB-D camera by introducing planes as well as points as features.This work is consisted of two steps: submap building and submap joining. Several adjacent keyframes, with the corresponding small patches, visual feature points, and planes observed from these keyframes, are used to build a submap. We fuse the submaps into a global map in a sequential fashion, such that, the global structure is recovered gradually through plane feature associations and optimization. We also show that the proposed algorithm can handle plane association problem incrementally in submap level, as the plane covariance can be obtained in each submap. The use of submap significantly reduces the computational cost during the optimization process, while keeping all information about planes. The proposed method is validated using both publicly available RGB-D benchmarks and datasets collected by authors. The algorithm can produce accurate trajectories and high quality 3D models on these challenging datasets, which are difficult for existing RGB-D SLAM or SFM algorithms.

Wocker, M, Wolf, P, Lindworsky, A & Deuse, J 2019, 'Opportunistische Instandhaltungsplanung in Flexiblen Fertigungssystemen', ZWF Zeitschrift für wirtschaftlichen Fabrikbetrieb, vol. 114, no. 5, pp. 250-254.
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Due to the com­plexity of flexible manufacturing systems (FMS), the economic effects of maintenance measures on plants during operation are often not quantifiable and unplannable yield losses occur. In order to consider the boundary condi­tions of FFS when planning maintenance meas­ures, the opportunistic maintenance is extend­ed by the consideration of the undirected mate­rial flow as well as parallel resources.

Wolf, P, Deuse, J & Richter, R 2019, 'Einfluss und Ursachen von Variabilität in der kunden-auftragsspezifischen Produktion', Zeitschrift für wirtschaftlichen Fabrikbetrieb, vol. 114, no. 11, pp. 730-733.
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Kurzfassung Zur Wahrung ihrer Wettbewerbsfähigkeit ist von Unternehmen mit kundenauftragsspezifischer Produktion ein hohes Maß an Flexibilität zum Umgang mit wertschöpfender und nicht wertschöpfender Variabilität erforderlich. Der vorliegende Beitrag definiert 14 Variabilitätskriterien inklusive mathematischer Beschreibungen dieser, die im Folgenden den Input einer auf die Bedürfnisse der kundenauftragsspezifischen Produktion angepassten variabilitätsberücksichtigenden Maschinenbelegungsplanung darstellen.

Woolfrey, J, Lu, W & Liu, D 2019, 'A Control Method for Joint Torque Minimization of Redundant Manipulators Handling Large External Forces', Journal of Intelligent & Robotic Systems, vol. 96, no. 1, pp. 3-16.
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© 2019, The Author(s). In this paper, a control method is developed for minimizing joint torque on a redundant manipulator where an external force acts on the end-effector. Using null space control, the redundant task is designed to minimize the torque required to oppose the external force, and reduce the dynamic torque. Furthermore, the joint motion can be weighted to factor in physical constraints such as joint limits, collision avoidance, etc. Conventional methods for joint torque minimization only consider the internal dynamics of the manipulator. If external forces acting on the end-effector are inadvertently implemented in to these control methods this could lead to joint configurations that amplify the resulting joint torque. The proposed control method is verified through two different case studies. The first case study involves simulation of high-pressure blasting. The second is a simulation of a manipulator lifting and moving a heavy object. The results show that the proposed control method reduces overall joint torque compared to conventional methods. Furthermore, the joint torque is minimized such that there is potential for a manipulator to execute certain tasks beyond its nominal payload capacity.

Woolfrey, J, Lu, W, Vidal-Calleja, T & Liu, D 2019, 'Clarifying clairvoyance: Analysis of forecasting models for near-sinusoidal periodic motion as applied to AUVs in shallow bathymetry', Ocean Engineering, vol. 190, pp. 106385-106385.
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© 2019 Elsevier Ltd This paper shows that Gaussian Process Regression (GPR) with a periodic kernel has better mean prediction accuracy and uncertainty bounds than time series or Fourier series when forecasting motion data of underwater vehicles subject to wave excitation. Many robotic systems, such as autonomous underwater vehicles (AUVs), are required to operate in environments with disturbances and relative motion that make task performance difficult. This motion often exhibits periodic, near-sinusoidal behaviour. By predicting this motion, control strategies can be developed to improve accuracy. Moreover, factoring in uncertainty can aid the robustness of these predictive control methods. Time series and Fourier series have been applied to several predictive control problems in a variety of fields. However, there are contradictory results in performance based on parameters, assessment criteria, and application. This paper seeks to clarify these discrepancies using AUV motion as a case study. GPR is also introduced as a third candidate for prediction based on previous applications to time series forecasting in other fields of science. In addition to assessing mean prediction accuracy, the ability of each model to adequately bound prediction error is also considered as a key performance indicator.

Wöstmann, R, Reckelkamm, T, Deuse, J, Kimberger, J, Temme, F, Schlunder, P & Klinkenberg, R 2019, 'Data-driven process optimization in the beverage industry', Fabriksoftware, vol. 24, no. 3, pp. 21-24.
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Increased pressure on prices and competition is presenting the beverage industry with major challenges in terms of rationalization. Existing Lean and Six Sigma approaches are reaching their limits in biochemical processes with complex multivariate influences. The paper presents an approach for data-driven process optimization in the beverage industry based on machine learning.

Ye, K & Ji, J 2019, 'Current, wave, wind and interaction induced dynamic response of a 5 MW spar-type offshore direct-drive wind turbine', Engineering Structures, vol. 178, pp. 395-409.
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© 2018 Elsevier Ltd This paper studies the dynamic response of a spar-type direct-drive wind turbine subjected to external and internal excitations. A free-free end model is developed for the wind turbine structure with a spar-type floating platform under deep sea condition. Firstly, the spar supported platform with tower structure is modelled as a rigid body while the nacelle is considered as a point mass attached on the top of the tower. Then the dynamic interaction between the drive-train system and the tower is considered by incorporating the modelling of a direct-drive drive-train system. The hydrodynamic and aerodynamic excitations applied include current, wave, and wind excitations as well as buoyant forces. The misalignments of the wind, wave and current are also considered to examine the induced response. With the help of the time history and FFT spectrum, the effects of both hydrodynamic and aerodynamic excitations along with the dynamic interaction between the drive-train system and tower structure on the dynamic behaviour of the spar-type floating platform are investigated under different sea conditions.

Yin, S, Ji, J, Deng, S & Wen, G 2019, 'Degenerate grazing bifurcations in a three-degree-of-freedom impact oscillator', Nonlinear Dynamics, vol. 97, no. 1, pp. 525-539.
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© 2019, Springer Nature B.V. This paper presents the analysis of the degenerate grazing bifurcation in a three-degree-of-freedom impact oscillator by studying the bifurcations of near-grazing period-one impact motion near the degenerate grazing point. Actually, this paper extends the higher-order zero time discontinuity mapping to perform the perturbation analysis of characteristic equation of period-one impact motion and obtains feasible eigenvalue approximation to study the potential bifurcations. The shooting method is applied to verify the validity of the derived approximation and corresponding computation results. In addition to the known bifurcation scenarios of saddle-node and period-doubling, novel Neimark–Sacker bifurcation and related co-dimension two bifurcation points of near-grazing period-one impact motion are also found to arise near the degenerate grazing point in a three-degree-of-freedom impact oscillator. For the in-depth understanding of near-grazing dynamics, the obtained results are compared with the reported results in the single- and two-degree-of-freedom impact oscillators.

Yu, H, Lu, W, Liu, D, Han, Y & Wu, Q 2019, 'Speeding up Gaussian Belief Space Planning for Underwater Robots Through a Covariance Upper Bound', IEEE Access, vol. 7, pp. 121961-121974.
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Yu, J, Ji, J, Miao, Z & Zhou, J 2019, 'Neural network-based region reaching formation control for multi-robot systems in obstacle environment', Neurocomputing, vol. 333, no. Automatica 53 53 2015, pp. 11-21.
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© 2018 Elsevier B.V. This study is concerned with the region reaching formation control problem with collision and obstacle avoidance for multi-robot systems in the presence of model uncertainties and external disturbances. A novel neural network based robust control scheme combining with the adaptive compensator and the adaptive control gain is proposed to achieve the region reaching formation control with collision and obstacle avoidance. It is shown that under the proposed control method, all the robots can always reach into the objective region, maintain their formation, and guarantee collision and obstacle avoidance. Illustrative examples are presented to show the effectiveness of the proposed control scheme.

zahrani, SA, Islam, MS & Saha, SC 2019, 'A thermo-hydraulic characteristics investigation in corrugated plate heat exchanger', Energy Procedia, vol. 160, pp. 597-605.
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© 2019 The Authors. Published by Elsevier Ltd. The amount of heat transfer from plate heat exchanger (PHE) is much higher compared with other types of conventional heat exchangers due to the high surface area of each plate. This study aims to investigate the heat transfer characteristics in a commercial corrugated PHE for sinusoidal corrugation type. A computational fluid dynamics (CFD) has been used to simulate the fluid flow inside the PHE for 1-1 single (water-water) and two (air-water) phase flow, counter arrangement. An advanced meshing technique has been used to generate the mesh for the PHE and a proper grid refinement test has been performed for the generated mesh. The overall investigation has been conducted for 60°/60° chevron angle plate (β) for a wide range of Re (500 ≤ Re ≤3000) and Prandtl number (Pr) (0.72 ≤ Pr ≤ 7.5). The result is validated with the benchmark experimental data. The impact of Reynolds and Pr has been investigated. The CFD results illustrate that the Nusselt number (Nu) increases with increasing of Reynolds number, while f decreasing with increasing of Re. The effect of Pr on Nusselt number and isothermal friction factor is presented. The corresponding correlations of Nu and f are developed from the CFD results.

Zhan, J, Ge, XJ, Huang, S, Zhao, L, Wong, JKW & He, SX 2019, 'Improvement of the inspection-repair process with building information modelling and image classification', Facilities, vol. 37, no. 7/8, pp. 395-414.
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PurposeAutomated technologies have been applied to facility management (FM) practices to address labour demands of, and time consumed by, inputting and processing manual data. Less attention has been focussed on automation of visual information, such as images, when improving timely maintenance decisions. This study aims to develop image classification algorithms to improve information flow in the inspection-repair process through building information modelling (BIM).Design/methodology/approachTo improve and automate the inspection-repair process, image classification algorithms were used to connect images with a corresponding image database in a BIM knowledge repository. Quick response (QR) code decoding and Bag of Words were chosen to classify images in the system. Graphical user interfaces (GUIs) were developed to facilitate activity collaboration and communication. A pilot case study in an inspection-repair process was applied to demonstrate the applications of this system.FindingsThe system developed in this study associates the inspection-repair process with a digital three-dimensional (3D) model, GUIs, a BIM knowledge repository and image classification algorithms. By implementing the proposed application in a case study, the authors found that improvement of the inspection-repair process and automated image classification with a BIM knowledge repository (such as the one developed in this study) can enhance FM practices by increasing productivity and reducing time and costs associated with ecision-making.Originality/valueThis study introduces an innovative approach th...

Zhang, X, Ji, J & Xu, J 2019, 'Parameter identification of time-delayed nonlinear systems: An integrated method with adaptive noise correction', Journal of the Franklin Institute, vol. 356, no. 11, pp. 5858-5880.
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© 2019 The Franklin Institute This paper proposes a novel method called the adaptive-noise-correction integrated parameter identification (ANCPI) for time-delayed nonlinear systems. Compared with the existing de-noising techniques, the significance of the proposed method is the use of the system itself to correct the noise-polluted components so that the accuracy of parameter identification is enhanced. To achieve the goal of adaptive noise correction, this study starts from the case of periodic response and then parameterizes the noise correction as the coefficient correction of harmonic basis. In this way, the parameter identification integrated with noise correction can be performed as the parameter optimization of the error function. For the convenience of application, a user-friendly program package is further provided and a detailed tutorial is presented in the supplementary material.

Zhang, Z, Oberst, S & Lai, JCS 2019, 'A non-linear friction work formulation for the analysis of self-excited vibrations', Journal of Sound and Vibration, vol. 443, pp. 328-340.
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Even though much research has been devoted to understand friction-induced vibrations, its root cause is not yet fully understood. Reliable prediction of friction-induced unstable vibrations such as in brake squeal or hip squeak remains a challenge because of nonlinearities involved and because the complex eigenvalue analysis (CEA) widely used in industry is linear. The energy fed back into the system by friction has been shown to be useful for analysis of measurements and numerical simulations. In numerical simulations, the linearised method of feed-in energy, calculated purely based on friction work has provided some insights into the physical mechanism for instabilities. However, the dynamics due to friction-induced instabilities is highly nonlinear and damping may offset some or all of the excess friction energy provided to the system. By using a nonlinear 2-DOF dry friction oscillator, a nonlinear friction work formulation is proposed to demonstrate that in combination with viscous damping the energy budget provides an improved analysis capability over linearised friction work. The results highlight the potential of nonlinear friction work as a reliable tool to study friction-induced instabilities to gain deeper physical insights into squeal triggering mechanisms and to better understand the over- and under-predictive character inherent to linear methods.

Zhao, J, Huang, S, Zhao, L, Chen, Y & Luo, X 2019, 'Conic Feature Based Simultaneous Localization and Mapping in Open Environment via 2D Lidar', IEEE Access, vol. 7, pp. 173703-173718.
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© 2013 IEEE. The conventional planar scan matching approach cannot cope well with the open environment as lacking of sufficient edges and corners. This paper presents a conic feature based simultaneous localization and mapping (SLAM) algorithm via 2D lidar which can adapt to an open environment nicely. The novelty of this work includes threefold: (1) defining a conic feature based parametrization approach; (2) developing a method to utilize feature's conic geometric information and odometry information since open environments are short of regular linear geometric features; (3) developing a factor graph based framework which can be adapted with the proposed parametrization. Simulation experiments and real environment experiments demonstrated that the proposed SLAM algorithm can get accurate and convincing results for the open environment and the map in our representation can express accurately the environment situation.

Zhao, L, Huang, S & Dissanayake, G 2019, 'Linear SLAM: Linearising the SLAM problems using submap joining', Automatica, vol. 100, pp. 231-246.
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© 2018 Elsevier Ltd The main contribution of this paper is a new submap joining based approach for solving large-scale Simultaneous Localization and Mapping (SLAM) problems. Each local submap is independently built using the local information through solving a small-scale SLAM; the joining of submaps mainly involves solving linear least squares and performing nonlinear coordinate transformations. Through approximating the local submap information as the state estimate and its corresponding information matrix, judiciously selecting the submap coordinate frames, and approximating the joining of a large number of submaps by joining only two maps at a time, either sequentially or in a more efficient Divide and Conquer manner, the nonlinear optimization process involved in most of the existing submap joining approaches is avoided. Thus the proposed submap joining algorithm does not require initial guess or iterations since linear least squares problems have closed-form solutions. The proposed Linear SLAM technique is applicable to feature-based SLAM, pose graph SLAM and D-SLAM, in both two and three dimensions, and does not require any assumption on the character of the covariance matrices. Simulations and experiments are performed to evaluate the proposed Linear SLAM algorithm. Results using publicly available datasets in 2D and 3D show that Linear SLAM produces results that are very close to the best solutions that can be obtained using full nonlinear optimization algorithm started from an accurate initial guess. The C/C++ and MATLAB source codes of Linear SLAM are available on OpenSLAM.

Zhao, S, Qiu, X, Lacey, J & Maisch, S 2019, 'Configuring fixed-coefficient active control systems for traffic noise reduction', Building and Environment, vol. 149, pp. 415-427.
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© 2018 Elsevier Ltd Practical implementation of active noise control (ANC) systems for outdoor traffic noise reduction remains rare. One challenge is the difficulty of configuring an ANC controller due to moving noise sources, which are typically located far from ANC systems. In this paper, a pseudo noise source method is proposed for configuring fixed-coefficient feedforward ANC systems for traffic noise control. First, a minimum of one pseudo noise source is placed near an ANC system to determine the control coefficients in the tuning stage. Second, the ANC systems are run to reduce the noise from far-field traffic noise sources using the optimal control coefficients in the cancelling stage. The feasibility and limitations of the proposed method are investigated by illustrating the effect of the pseudo noise source position on the noise reduction performance of the ANC system. The simulation results show that the performance of the ANC system increases with distance when the pseudo noise sources move farther from the system but approaches a constant when the pseudo noise sources are in the far field. The indoor experimental results are consistent with the simulation results. The outdoor experimental results of a six-channel coupled system show a noise reduction of 3 dB below 500 Hz at the position of a dummy head.

Abdo, P, Huynh, BP, Braytee, A & Taghipour, R 1970, 'Effect of Phase Change Material on Temperature in a Room Fitted With a Windcatcher', Volume 7: Fluids Engineering, ASME 2019 International Mechanical Engineering Congress and Exposition, American Society of Mechanical Engineers.
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Abstract Global warming and climate change have been considered as major challenges over the past few decades. Sustainable and renewable energy sources are nowadays needed to overcome the undesirable consequences of rapid development in the world. Phase change materials (PCM) are substances with high latent heat storage capacity which absorb or release the heat from or to the surrounding environment. They change from solid to liquid and vice versa. PCMs could be used as a passive cooling method which enhances energy efficiency in buildings. Integrating PCM with natural ventilation is investigated in this study by exploring the effect of phase change material on the temperature in a room fitted with a windcatcher. A chamber made of acrylic sheets fitted with a windcatcher is used to monitor the temperature variations. The dimensions of the chamber are 1250 × 1000 × 750 mm3. Phase change material is integrated respectively at the walls of the room, its floor and ceiling and within the windcatchers inlet channel. Temperature is measured at different locations inside the chamber. Wind is blown through the room using a fan with heating elements.

Abdo, P, Taghipour, R & Huynh, BP 1970, 'Three Dimensional Simulation of the Effect of Windcatcher’s Inlet Shape', Volume 2: Computational Fluid Dynamics, ASME-JSME-KSME 2019 8th Joint Fluids Engineering Conference, American Society of Mechanical Engineers, San Francisco, CA, USA, pp. 1-8.
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Abstract Windcatcher has been used over centuries for providing natural ventilation using wind power, it is an effective passive method to provide healthy and comfortable indoor environment. The windcatcher’s function is based on the wind and on the stack effect resulting from temperature differences. Generally, it is difficult for wind to change its direction, and enter a room through usual openings, the windcatcher is designed to overcome such problems since they have vertical columns to help channel wind down to the inside of a building. The efficiency of a windcatcher is maximized by applying special forms of opening and exit. The openings depend on the windcatcher’s location and on its cross sectional area and shape such as square, rectangular, hexagonal or circular. In this study the effect of the inlet design is investigated to achieve better air flow and increase the efficiency of windcatchers. To achieve this, CFD (computational fluid dynamics) tool is used to simulate the air flow in a three dimensional room fitted with a windcatcher based on the different inlet designs. The divergent inlet has captured the highest air flow with a difference of approximately 3% compared to the uniform inlet and 5% difference compared to the bulging-convergent inlet.

Abdo, P, Taghipour, R & Huynh, BP 1970, 'Three Dimensional Simulation Of Ventilation Flow Through A Solar Windcatcher', Proceedings of The ASME - JSME - KSME Joint Fluids Engineering Conference 2019, The ASME - JSME - KSME Joint Fluids Engineering Conference 2019, ASME, San Francisco, CA, USA, pp. 1-6.
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Natural ventilation is the process of supplying and removing air through an indoor space by natural means. There are two types of natural ventilation occurring in buildings: winddriven ventilation and buoyancy driven or stack ventilation. The most efficient design for natural ventilation in buildings should implement both types of natural ventilation. Stack ventilation which is temperature induced is driven by buoyancy making it less dependent on wind and its direction. Heat emitted causes a temperature difference between two adjoining volumes of air, the warmer air will have lower density and be more buoyant thus will rise above the cold air creating an upward air stream. Combining the wind driven and the buoyancy driven ventilation will be investigated in this study through the use of a windcatcher natural ventilation system. Stack driven air rises as it leaves the windcatcher and it is replaced with fresh air from outside as it enters through the positively pressured windward side.

Aldini, S, Akella, A, Singh, AK, Wang, Y-K, Carmichael, M, Liu, D & Lin, C-T 1970, 'Effect of Mechanical Resistance on Cognitive Conflict in Physical Human-Robot Collaboration', 2019 International Conference on Robotics and Automation (ICRA), 2019 International Conference on Robotics and Automation (ICRA), IEEE, Canada, pp. 6137-6143.
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© 2019 IEEE. Physical Human-Robot Collaboration (pHRC) is about the interaction between one or more human operator(s) and one or more robot(s) in direct contact and voluntarily exchanging forces to accomplish a common task. In any pHRC, the intuitiveness of the interaction has always been a priority, so that the operator can comfortably and safely interact with the robot. So far, the intuitiveness has always been described in a qualitative way. In this paper, we suggest an objective way to evaluate intuitiveness, known as prediction error negativity (PEN) using electroencephalogram (EEG). PEN is defined as a negative deflection in event related potential (ERP) due to cognitive conflict, as a consequence of a mismatch between perception and reality. Experimental results showed that the forces exchanged between robot and human during pHRC modulate the amplitude of PEN, representing different levels of cognitive conflict. We also found that PEN amplitude significantly decreases (mathrm {p} lt 0.05) when a mechanical resistance is being applied smoothly and more time in advance before an invisible obstacle, when compared to a scenario in which the resistance is applied abruptly before the obstacle. These results indicate that an earlier and smoother resistance reduces the conflict level. Consequently, this suggests that smoother changes in resistance make the interaction more intuitive.

Aldini, S, Carmichael, MG & Liu, D 1970, 'A risk reduction framework for design of physical human-robot collaboration', Australasian Conference on Robotics and Automation, ACRA, Australasian Conference on Robotics and Automation, Adelaide.
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As robots designed to physically interact with humans become common in various application areas, shared workspaces and force exchange between human and robot lead to new challenges in terms of safety. Often, a variety of safety techniques is necessary, and deciding what methods to include in a comprehensive safety framework is not an easy task. This paper is concerned with the design of robotic co-wokers that involve physical Human-Robot Collaboration (pHRC), with humans and robots in continuous direct physical contact and exchanging forces. A hierarchical risk reduction framework is presented for guiding the design of robotic co-workers to reduce the risk associated with hazards commonly found in pHRC tasks. A case study is presented to demonstrate the use of the framework in designing an Assistance-as-Needed roBOT (ANBOT) which has been extensively tested in practical industry applications.

Arukgoda, J, Ranasinghe, R & Dissanayake, G 1970, 'Representation of Uncertain Occupancy Maps with High Level Feature Vectors', 2019 IEEE 15th International Conference on Automation Science and Engineering (CASE), 2019 IEEE 15th International Conference on Automation Science and Engineering (CASE), IEEE, Vancouver, BC, Canada, pp. 1035-1041.
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© 2019 IEEE. This paper presents a novel method for representing an uncertain occupancy map using a 'feature vector' and an associated covariance matrix. Input required is a point cloud generated using observations from a sensor captured at different locations in the environment. Both the sensor locations and the measurements themselves may have an associated uncertainty. The output is a set of coefficients and their uncertainties of a cubic spline approximation to the distance function of the environment, thereby resulting in a compact parametric representation of the environment geometry. Cubic spline coefficients are computed by solving a non-linear least squares problem that enforces the Eikonal equation over the space in which the environment geometry is defined, and zero boundary condition at each observation in the point cloud. It is argued that a feature based representation of point cloud maps acquired from uncertain locations using noisy sensors has the potential to open up a new direction in robot mapping, localisation and SLAM. Numerical examples are presented to illustrate the proposed technique.

Arukgoda, J, Ranasinghe, R & Dissanayake, G 1970, 'Robot Localisation in 3D Environments Using Sparse Range Measurements', 2019 IEEE/ASME International Conference on Advanced Intelligent Mechatronics (AIM), 2019 IEEE/ASME International Conference on Advanced Intelligent Mechatronics (AIM), IEEE, Hong Kong, pp. 551-558.
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© 2019 IEEE. This paper presents an algorithm for mobile robot localisation given a map of a 3D environment and a sparse set of range-bearing measurements. The environment is represented using a spline approximation of its vector distance function (VDF). For a given location in the environment, VDF encodes the distance to the nearest occupied region along three orthogonal axes. VDF is first obtained from an occupancy voxel map and its three components are then approximated in the least-square sense using a set of three dimensional cubic b-splines, providing a rich and continuous representation of the environment. First and second order derivatives of the VDF are also computed and stored. The difference between an observed range measurement in a given direction and its expected value is formulated as a function of the robot location and the spline coefficients representing the VDF. This leads to a non-linear least-squares optimization problem that can be solved to localise the robot given a set of such measurements. It is demonstrated that a sparse set of range-bearing measurements, an order of magnitude smaller than what is typically available from 3D range sensor is adequate to achieve accurate localisation. The algorithm presented is illustrated using a number of examples including a single point range sensor mounted on a pan-tilt head to localise a robot moving in an indoor environment.

Barthelmey, A, Lee, E, Hana, R & Deuse, J 1970, 'Dynamic digital twin for predictive maintenance in flexible production systems', IECON 2019 - 45th Annual Conference of the IEEE Industrial Electronics Society, IECON 2019 - 45th Annual Conference of the IEEE Industrial Electronics Society, IEEE, Lisbon, Portugal, pp. 4209-4214.
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© 2019 IEEE. Technical innovations to improve production systems flexibility have been extensively investigated and are already available to industrial practice. However, the production companies' internal structures and processes must also meet these flexibility requirements in order for system adjustments to be efficiently carried out. Due to the direct influence on availability, performance and quality losses, maintenance is particularly relevant. Therefore, this paper considers the effects of flexibility on the promising strategy of predictive maintenance. With the digital twin, its update service and a labelling interface, the essential components of a predictive maintenance system for flexible production systems are introduced in detail. This application is based on a reference plant in the form of a flexible hybrid assembly system. The outlook discusses the transferability to other industrial use cases.

Becerril, L, Guertler, M & Longa, E 1970, 'Developing Design Methods - a Conceptual Requirement Framework', Proceedings of the Design Society: International Conference on Engineering Design, Proceedings of the Design Society: International Conference on Engineering Design, Cambridge University Press (CUP), Delft, Netherlands, pp. 1463-1472.
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AbstractDesign methods can provide valuable support in structuring and solving complex product design problems. However, the application and the transfer of methods from academia to industry is limited. To date, research has tended to focus on solving this through improved method selection, method adaptation and training. The development of design methods itself has attracted surprisingly low attention. This paper closes this gap and adds a quite new perspective of systematic requirement management of method development. However, the variety of methods, method users and application contexts is a key challenge and does not allow for a universal set of requirements. Thus, this paper transfers the concept of solution-neutral requirements frameworks, which are established in product design, to method development. The framework is derived from analysing and structuring different requirements found in literature. Different requirement sub-/categories allow for accommodating the varying levels of detail of requirements. The framework works like a checklist and helps design researchers to consider the most important requirement categories, which subsequently can be detailed project-specifically.

Best, G & Hollinger, GA 1970, 'Decentralised self-organising maps for the online orienteering problem with neighbourhoods', 2019 International Symposium on Multi-Robot and Multi-Agent Systems (MRS), 2019 International Symposium on Multi-Robot and Multi-Agent Systems (MRS), IEEE.
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Carmichael, MG, Aldini, S, Khonasty, R, Tran, A, Reeks, C, Liu, D, Waldron, KJ & Dissanayake, G 1970, 'The ANBOT: An Intelligent Robotic Co-worker for Industrial Abrasive Blasting', 2019 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 2019 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), IEEE, Macau, China, pp. 8026-8033.
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© 2019 IEEE. We present the ANBOT, an intelligent robotic coworker for physical human-robot collaboration. The ANBOT system assists workers performing industrial abrasive blasting, shielding them from the large forces experienced during this physically demanding task. The co-operative robotic system combines the strength and endurance of robots with the decision making of skilled workers. The inherent challenges in human-robot collaboration, combined with the difficult blasting environment required novel design decisions to be made and new solutions to be developed. These include an approach for handling kinematic singularities in a manner suitable for human-robot co-operation, estimating worker pose under poor visibility conditions, and an intuitive control scheme that adapts the robotic assistance based on the estimated strength of the worker. In this work we summarise the ANBOT system and present findings from preliminary site trials. The trials included several real industrial blasting tasks under the control of a skilled abrasive blasting worker who had no experience working alongside a robot. Results demonstrate the suitability of the ANBOT for practical industrial applications.

Cetindamar, D, Kocaoglu, D, Lammers, T & Merigo, JM 1970, 'A Bibliometric Analysis of Technology Management Research at PICMET for 2009–2018', 2019 Portland International Conference on Management of Engineering and Technology (PICMET), 2019 Portland International Conference on Management of Engineering and Technology (PICMET), IEEE, Portland, Oregon, pp. 1-5.
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© 2019 PICMET. The Portland International Centre for Management of Engineering and Technology (PICMET) was established in 1989. It has since become one of the leading organizations in the field of management of engineering and technology in the world. PICMET provides a strong platform for academicians, industry professionals and government representatives to exchange new knowledge derived from both research and implementation of technology management. To celebrate its 30-year journey, and to show the trends in technology management research and implementation over the past ten years (2009-2018), this paper presents a bibliometric analysis of the more than 3000 papers accepted for inclusion in PICMET conferences. The study highlights the topics, authors, journals and countries where significant research on technology management is conducted.

Chen, Y, Huang, S, Fitch, R, Zhao, L, Yu, H & Yang, D 1970, 'On-line 3D active pose-graph SLAM based on key poses using graph topology and sub-maps', 2019 International Conference on Robotics and Automation (ICRA), 2019 International Conference on Robotics and Automation (ICRA), IEEE, Montreal, CANADA, pp. 169-175.
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© 2019 IEEE. In this paper, we present an on-line active pose-graph simultaneous localization and mapping (SLAM) frame-work for robots in three-dimensional (3D) environments using graph topology and sub-maps. This framework aims to find the best trajectory for loop-closure by re-visiting old poses based on the T-optimality and D-optimality metrics of the Fisher information matrix (FIM) in pose-graph SLAM. In order to reduce computational complexity, graph topologies are introduced, including weighted node degree (T-optimality metric) and weighted tree-connectivity (D-optimality metric), to choose a candidate trajectory and several key poses. With the help of the key poses, a sampling-based path planning method and a continuous-time trajectory optimization method are combined hierarchically and applied in the whole framework. So as to further improve the real-time capability of the method, the sub-map joining method is used in the estimation and planning process for large-scale active SLAM problems. In simulations and experiments, we validate our approach by comparing against existing methods, and we demonstrate the on-line planning part using a quad-rotor unmanned aerial vehicle (UAV).

Geekiyanage, N, Sauret, E, Saha, S, Flower, R & Gu, Y 1970, 'Modelling the deformation behavior of stomatocyte, discocyte and echinocyte red blood cell morphologies during optical tweezers stretching', 6th International Conference on Computational and Mathematical Biomedical Engineering – CMBE2019, International Conference on Computational and Mathematical Biomedical Engineering, Zeta Computational Resources Ltd, Japan, pp. 157-160.
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A coarse-grained (CG) red blood cell (RBC) membrane model is used to investigate the deformation behavior of stomatocyte, discocyte and echinocyte morphologies during optical tweezers stretching. First, the numerically predicted discocyte deformation behavior is validated against analogous experimental observations, and then the numerically predicted stomatocyte and echinocyte deformation behavior is compared to the discocyte deformation behavior. The findings indicate that the CG-RBC membrane model is capable of accurately predicting the deformation behavior of stomatocyte, discocyte and echinocyte RBC morphologies during optical tweezers stretching, and an applicable tool to investigate the evolution of RBC behavior and membrane properties for differentmorphologies.

Giovanangeli, N, Piyathilaka, L, Kodagoda, S, Thiyagarajan, K, Barclay, S & Vitanage, D 1970, 'Design and Development of Drill-Resistance Sensor Technology for Accurately Measuring Microbiologically Corroded Concrete Depths', Proceedings of the International Symposium on Automation and Robotics in Construction (IAARC), 36th International Symposium on Automation and Robotics in Construction, International Association for Automation and Robotics in Construction (IAARC), Canada, pp. 735-735.
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© 2019 International Association for Automation and Robotics in Construction I.A.A.R.C. All rights reserved. Microbial corrosion of concrete is a severe problem that significantly reduces the service life of underground sewers in countries around the globe. Therefore, water utilities are actively looking for in-situ sensors that can quantify the biologically induced concrete corrosion levels, in order to carry out preventive maintenance before any catastrophic failures. As a solution, this paper introduces a drill-resistance based sensor that can accurately measure the depth of the microbiologically corroded concrete layer. A prototype sensor was developed and evaluated in laboratory test conditions. The lab experiments proved that the developed sensor has the ability to measure the depth of the microbiologically corroded concrete with millimeter level of accuracy. Additionally, the sensor can also locate and accurately measure the size of concrete aggregates as well as potential cracks, effectively creating a sub-surface ‘scan’ of the concrete at the targeted point of interest. Therefore, providing valuable extra information for assessing the condition of the sewer concrete.

Gunatilake, A, Piyathilaka, L, Kodagoda, S, Barclay, S & Vitanage, D 1970, 'Real-Time 3D Profiling with RGB-D Mapping in Pipelines Using Stereo Camera Vision and Structured IR Laser Ring', Proceedings of the 14th IEEE Conference on Industrial Electronics and Applications, ICIEA 2019, IEEE Conference on Industrial Electronics and Applications, IEEE, Xi'an, China, pp. 916-921.
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This paper is focused on delivering a solution that can scan and reconstructthe 3D profile of a pipeline in real-time using a crawler robot. A structuredinfrared (IR) laser ring projector and a stereo camera system are used togenerate the 3D profile of the pipe as the robot moves inside the pipe. Theproposed stereo system does not require field calibrations and it is notaffected by the lateral movement of the robot, hence capable of producing anaccurate 3D map. The wavelength of the IR light source is chosen to be nonoverlapping with the visible spectrum of the color camera. Hence RGB colorvalues of the depth can be obtained by projecting the 3D map into the colorimage frame. The proposed system is implemented in Robotic Operating System(ROS) producing real-time RGB-D maps with defects. The defect map exploitdifferences in ovality enabling real-time identification of structural defectssuch as surface corrosion in pipe infrastructure. The lab experiments showedthe proposed laser profiling system can detect ovality changes of the pipe withmillimeter level of accuracy and resolution.

Hadgraft, R, Francis, B, Brown, T, Fitch, R & Halkon, B 1970, 'Renewing Mechanical and Mechatronics Programs', AAEE2019, AAEE2019, Brisbane, Australia.

Halkon, B 1970, 'On the possibility of UAV-mounted LDVS for response-only dynamic characterisation of remote infrastructure', 8th IOMAC - International Operational Modal Analysis Conference, Proceedings, International Operational Modal Analysis Conference, Curran, Copenhagen, pp. 547-551.
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Laser Doppler vibrometers are technically well suited to general application but they offer special benefits in a variety of challenging measurement scenarios which are now well documented and accepted. An interesting and potentially powerful example of such a challenging measurement scenario is one where the laser vibrometer is mounted on/in an unmanned aerial vehicle in order that autonomous measurement campaigns can be undertaken in remote and/or harsh environments. One important challenge to overcome in such a scenario is the measurement sensitivity to vibration of the instrument itself or indeed of any steering optics used to point the probe laser beam toward the target of interest. In this paper, recently reported means by which this measurement sensitivity can be rectified by simultaneously obtained correction measurements will be described. Specifically, this development opens up the possibility of laser Doppler vibrometry from unmanned aerial vehicles for response-only dynamic assessment of remote infrastructure, a measurement challenge of significant potential value.

Halkon, B, Rauter, A, Oberst, S & Marburg, S 1970, 'Research and development of an air-puff excitation system for lightweight structures', 8th IOMAC - International Operational Modal Analysis Conference, Proceedings, International Operational Modal Analysis Conference, Curran Associates, Copenhagen, Denmark, pp. 627-634.
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Lightweight, thin-walled structures appear in numerous engineering and natural structures. Due to their sensitivity, vibration excitation by, now traditional, contacting techniques, such as modally-tuned impact hammers or electrodynamic shakers, to investigate their dynamics is challenging since it typically adds substantial mass and/or stiffness at the excitation location. The research presented in this article, therefore, is intended to yield a system for the non-contact excitation of thin-walled structures through small, controlled blasts of air. An air-puff system, consisting of two fast-acting solenoid-controlled valves, a small air outlet nozzle and bespoke control software with a programmable valve control sequence, is researched and developed. The excitation impulse characteristics are investigated experimentally and described in detail for varying input control parameters. Ultimately, suitability of the system for the excitation of thin-walled structures is explored, for both a 3D-printed micro-satellite panel and a natural bee honeycomb, with promising results when compared to that of an impact hammer.

Haque, MJ, Molla, MM, Akhter, N & Saha, SC 1970, 'Multiple-relaxation-time lattice Boltzmann simulation of natural convection flow in a partitioned cavity using GPU computing', AIP Conference Proceedings, 8TH BSME INTERNATIONAL CONFERENCE ON THERMAL ENGINEERING, AIP Publishing, Dhaka, Bangladesh.
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© 2019 Author(s). In this paper, we demonstrated the implementation of General Purpose Graphics Processing Unit (GPGPU) programming in Compute Unified Device Architecture (CUDA) C for the simulation of natural convection flow in a side-heated three-dimensional (3D) rectangular cavity with a partition. In the present lattice Boltzmann method (LBM) D3Q19 multiple-relaxation-time (MRT) and D3Q6 single relaxation-time (SRT) model are implemented for the simulation of fluid flow and temperature phenomena, respectively. The parallel code is validated with the benchmark problem of a side heated cubic cavity. The results are presented by the temperature distribution in terms of isotherms, local and average Nusselt number and 3D view of iso-surface for the different Rayleigh number (Ra) and the Prandtl number fixed at Pr = 0.71. It is also observed that the present parallel implementation of the MRT-lattice Boltzmann simulation in GPU has a substantial computational effciency rather than the sequential programming in central processing units (CPU).

Harcombe, DM, Ruppert, MG & Fleming, AJ 1970, 'Modeling and Noise Analysis of a Microcantilever-based Mass Sensor', 2019 International Conference on Manipulation, Automation and Robotics at Small Scales (MARSS), 2019 International Conference on Manipulation, Automation and Robotics at Small Scales (MARSS), IEEE.
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Hayati, H & Eager, D 1970, 'Additional injury prevention criteria for impact attenuation surfacing used in children’s playgrounds', 14th Australasian Injury Prevention and Safety Promotion, 14th Australasian Injury Prevention and Safety Promotion, Brisbane.

Hayati, H, Eager, D & Walker, P 1970, 'A SLIP Model to predict the dynamics of rapid tetrapod locomotion during hind-leg single support', International Society of Biomechanics Conference.

Hayati, H, Eager, D & Walker, P 1970, 'An impact attenuation surfacing test to analyse the dynamic behaviour of greyhound racetrack sand surface', WEC2019: World Engineers Convention 2019, World Engineers Conventio, Engineers Australia, Melbourne, Australia, pp. 391-401.
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The underfoot surface affects the dynamics of legged locomotion of any kind from a legged robot to a racing greyhound. In racing greyhounds, the surface is one of the leading risk factors contributing to life-threatening injuries. The current standard type of material used in greyhound racing tracks is sand. Two variables affect the sand functional behaviour, namely: the moisture content; and rate of compaction. This paper analyses the effect of altering the moisture content and density on the dynamic behaviour of the sand surface. This paper also presents a method to obtain the mechanical coefficients of the surface via an standard impact test which was applied as an input in the legged locomotion simulation over compliant terrains. The results show that a sand sample with the 20% moisture content and density of 1.35 g/cm3 has the most favourable behaviour with regards to injury prevention.

Hayati, H, Mahdavi, F & Eager, D 1970, 'A single IMU to capture the fundamental dynamics of rapid tetrapod locomotion: Racing greyhounds', European Society of Biomechanics, European Society of Biomechanics, Vienna, Austria.

Hirschmanner, M, Tsiourti, C, Patten, T & Vincze, M 1970, 'Virtual Reality Teleoperation of a Humanoid Robot Using Markerless Human Upper Body Pose Imitation', 2019 IEEE-RAS 19th International Conference on Humanoid Robots (Humanoids), 2019 IEEE-RAS 19th International Conference on Humanoid Robots (Humanoids), IEEE.
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Hossain, MI, Eager, D & Walker, P 1970, 'Simulation of Racing Greyhound Kinematics', Proceedings of the 9th International Conference on Simulation and Modeling Methodologies, Technologies and Applications, 9th International Conference on Simulation and Modeling Methodologies, Technologies and Applications, SCITEPRESS - Science and Technology Publications, Prague, Czech Republic, pp. 47-56.
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Copyright © 2019 by SCITEPRESS – Science and Technology Publications, Lda. All rights reserved. This paper outlines greyhound dynamics results for yaw rate, speed, and the congestion pattern during a race derived through numerical modelling. The simulation results presented are also correlated to actual race data to validate modelling performance and reliability. The tasks carried out include the development of a numerical model for greyhound veering and race related supporting models, creating track 3D models replicated from actual survey data of the track, establishing a simulation environment that emulates an actual greyhound race, and the processing of both simulation and actual race data. The results show that greyhounds are susceptible to experience varying high acceleration in first five seconds into the race, during which a minimum average forward acceleration of 3.9 m/s2 was calculated, a peak yaw rate magnitude of 0.4 rad/s before the bend while transitioning into the track, and congestion during a race is affected by lure driving performance.

Huimin, C, Feng, X, Suvash, CS & Qingkuan, L 1970, 'Asymmetric natural convection flow in three dimensional attic space', AIP Conference Proceedings, CENTRAL EUROPEAN SYMPOSIUM ON THERMOPHYSICS 2019 (CEST), AIP Publishing, Rhodes, Greece.
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© 2019 Author(s). Natural convection in an attic space with top cooling is investigated by three dimensional numerical simulation for a wide range of Rayleigh numbers. The numerical results show the development of natural convection flow in attic space. Three stages: an initial stage, a transitional stage and a fully developed stage are involved. At higher Rayleigh numbers, the flow in the attic space is three dimensional and asymmetry with respect to geometric symmetry plane. The critical Rayleigh number for asymmetric flow is found.

Hyun, J-S, Carmichael, MG, Tran, A, Zhang, S & Liu, D 1970, 'Evaluation of Fast, High-detail Projected Light 3D Sensing for Robots in Construction', 2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA), 2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA), IEEE, Xi'an, China, pp. 1262-1267.
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© 2019 IEEE. Robots used on-site in construction need to perceive the surrounding environment to operate autonomously. This is challenging as the construction environment is often less than ideal due to changing lighting conditions, turbid air, and the need to detect fine details. In this work we evaluate a custom made projected light 3D sensor system for suitability and practicality in enabling autonomous robotics for construction. A series of tests are performed to evaluate the sensor based on ability to capture environmental details, operate robustly in challenging lighting conditions, and make accurate geometric measurements. Analysis shows that high fidelity measurements with accuracy in the order of millimeters can be obtained, making the technology a promising solution for robots operating in construction environments.

Jayasuriya, M, Dissanayake, G, Ranasinghe, R & Gandhi, N 1970, 'Leveraging Deep Learning Based Object Detection for Localising Autonomous Personal Mobility Devices in Sparse Maps.', ITSC, IEEE Intelligent Transportation Systems Conference, IEEE, Auckland, New Zealand, pp. 4081-4086.
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© 2019 IEEE. This paper presents a low cost, resource efficient localisation approach for autonomous driving in GPS denied environments. One of the most challenging aspects of traditional landmark based localisation in the context of autonomous driving, is the necessity to accurately and frequently detect landmarks. We leverage the state of the art deep learning framework, YOLO (You Only Look Once), to carry out this important perceptual task using data obtained from monocular cameras. Extracted bearing only information from the YOLO framework, and vehicle odometry, is fused using an Extended Kalman Filter (EKF) to generate an estimate of the location of the autonomous vehicle, together with it's associated uncertainty. This approach enables us to achieve real-time sub metre localisation accuracy, using only a sparse map of an outdoor urban environment. The broader motivation of this research is to improve the safety and reliability of Personal Mobility Devices (PMDs) through autonomous technology. Thus, all the ideas presented here are demonstrated using an instrumented mobility scooter platform.

Kalhori, H, Halkon, B & Alamdari, MM 1970, 'Wavelet transform-based strategy for identifying impact force on a composite panel', Proceedings of the 26th International Congress on Sound and Vibration, ICSV 2019, International Congress on Sound and Vibration, Montreal, Canada.
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An algorithm based on wavelet analysis for automatically estimating the location and magnitude of impact forces exerted on a rectangular carbon fibre-epoxy honeycomb composite panel is developed. The technique employs a single piezoelectric sensor mounted distant from the impact zone and presumes that an impact is applied at one of several pre-established locations. Furthermore, it is presumed that the recorded vibration response is the superposition of the simultaneous 'assumed' impacts at these locations, with the aim of simultaneously identifying the actual impact location and force magnitude through an under-determined regularisation scheme. The algorithm aims to detect the most probable impact location amongst the spurious locations. Since a normal impact introduces a narrow-band time-localised event with high energy, the wavelet transform is an effective tool to locate this event, with the wavelet coefficient representing how closely correlated the wavelet is with the reconstructed forces. The larger the coefficient is in absolute value, the greater the similarity. As a case study, an under-determined problem with four potential impact locations is considered. The results demonstrate successful localisation and reconstruction of the impact force using both orthogonal and non-orthogonal wavelets

Kane, DM, Snowdon, B, Blamires, SJ & Little, DJ 1970, 'Orb web spider silks: how their optics affects potential visibility', AOS Australian Conference on Optical Fibre Technology (ACOFT) and Australian Conference on Optics, Lasers, and Spectroscopy (ACOLS) 2019, AOS Australian Conference on Optical Fibre Technology (ACOFT) and Australian Conference on Optics, Lasers, and Spectroscopy (ACOLS) 2019, SPIE.
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Katic, M, Cetindamar, D, Agarwal, R & Sick, N 1970, 'Operationalising Ambidexterity: The Role of 'Better' Management Practices in High-Variety, Low-Volume Manufacturing', 2019 Portland International Conference on Management of Engineering and Technology (PICMET), 2019 Portland International Conference on Management of Engineering and Technology (PICMET), IEEE, Portland, Oregon, pp. 1-10.
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Lai, Y, Sutjipto, S, Carmichael, M & Paul, G 1970, 'Heuristic Detection of Recovery Progress using Robotic Data', 2019 IEEE International Conference on Cybernetics and Intelligent Systems (CIS) and IEEE Conference on Robotics, Automation and Mechatronics (RAM), 2019 IEEE International Conference on Cybernetics and Intelligent Systems (CIS) and IEEE Conference on Robotics, Automation and Mechatronics (RAM), IEEE, Bangkok, Thailand, pp. 506-511.
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Assessment methods for rehabilitation and recovery have recently been the focal point of research for medical professionals and engineers alike. Current assessment protocols rely on historical ordinal metrics which have been disputed despite their inter-rater reliability. Contemporary kinematic measures have allowed for new approaches to assess recovery progress. However, the abundance of data has deterred medical professionals from adopting these new protocols. This paper presents a method, based on the RMSE-LWSS (Longest Warping Subsequence) score, to distinguish outliers from systemic change for updating the personalized exercise path for users. By treating change detection as a classification problem, the incorporation of a compromised path based on the user's current capability is possible. Experiments were conducted to verify the efficacy of the method, comparing against statistical techniques for change detection and classification of pre-determined paths. The paper highlights how readily available data, rather than complex sensor systems, can be utilized to improve the robustness of personalization capabilities for robotic rehabilitation systems.

Lammers, T, Tomidei, L & Trianni, A 1970, 'Towards a Novel Framework of Barriers and Drivers for Digital Transformation in Industrial Supply Chains', 2019 Portland International Conference on Management of Engineering and Technology (PICMET), 2019 Portland International Conference on Management of Engineering and Technology (PICMET), IEEE, Portland.
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© 2019 PICMET. Businesses across all sectors are facing the complexity of an increasingly digital economy. Digital transformation offers vast opportunities to businesses and entire supply chains. While many investments are targeted at the organization level, the supply chain perspective can lead to even greater impacts on business performance. However, as supply chains involve interconnections between multiple actors, comprehensive digitalization initiatives at this level are very complex. Several strategic factors affect decision-making around digital investments. For this reason, a framework that categorizes all these factors is needed in order to help managers build digitalization strategies for their supply chains. In this paper, based on a review of existing literature, we give indications for a framework encompassing barriers to and drivers for digital transformation in the context of industrial supply chains. Our framework preliminarily allocates these factors by using two dimensions. The first one classifies them using several categories: financial, knowledge and skills, regulatory, technological, market, organizational, and cultural. The second dimension classifies determinants at the level on which actions can be made, i.e. market, supply chain, or organization. The framework can support organizations to exploit the opportunities provided by digitalization of supply chains and will help managers understand the complexity involved.

Lu, S, Oberst, S, Zhang, G & Luo, Z 1970, 'Period adding bifurcations in dynamic pricing processes', 2019 IEEE Conference on Computational Intelligence for Financial Engineering & Economics (CIFEr), 2019 IEEE Conference on Computational Intelligence for Financial Engineering & Economics (CIFEr), IEEE, Shenzhen, China, pp. 71-76.
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Price information enables consumers to anticipate a price and to make purchasing decisions based on their price expectations, which are critical for agents with pricing decisions or price regulations. A company with pricing decisions can aim to optimise the short-term or the long-term revenue, each of which leads to different pricing strategies thereby different price expectations. Two key ingredients play important roles in the choosing of the short-term or the long-term optimisation objectives: the maximal revenue and the robustness of the chosen pricing strategy against market volatility. However the robustness is rarely identified in a volatile market. Here, we investigate the robustness of optimal pricing strategies with the short-term or long-term optimisation objectives through the analysis of nonlinear dynamics of price expectations. Bifurcation diagrams and period diagrams are introduced to compare the change in dynamics of the optomal pricing strategies. Our results highlight that period adding bifurcations occur during the dynamic pricing processes studied. These bifurcations would challenge the robustness of an optimal pricing strategy. The consideration of the long-term revenue allows a company to charge a higher price, which in turn increases the revenue. However, the consideration of the short-term revenue can reduce the occurrence of period adding bifurcations, contributing to a robust pricing strategy. For a company, this strategy is a robust guarantee of optimal revenue in a volatile market; for consumers, this strategy avoids rapid changes in price and reduce their dissatisfaction of price variations.

Mahdavi, F, Hayati, H, Kennedy, P & Eager, D 1970, 'Ageing and resulting injuries – effects on racing greyhounds', European Society of Biomechanics, European Society of Biomechanics, Vienna, Austria.

Melnikov, A, Chiang, YK, Oberst, S, Quan, L, Alu, A, Marburg, S & Powell, D 1970, 'Experimental validation of maximal Willis coupling in an acoustic meta-atom', 13th International Congress on Artificial Materials for Novel Wave Phenomena – Metamaterials 2019, International Congress on Artificial Materials for Novel Wave Phenomena, Rome, pp. 1-2.
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Willis coupling is the acoustic analog of bianisotropy, representing coupling between the monopolar and dipolar degrees of freedom. It has recently been theoretically demonstrated that there is an upper bound on the strength of this coupling, imposed by the conservation of energy. Here we present a scalable meta-atom design, and experimentally demonstrate that it approaches the theoretical limit for Willis coupling.

Munasinghe, N, Miles, L & Paul, G 1970, 'Direct-Write Fabrication of Wear Profiling IoT Sensor for 3D Printed Industrial Equipment', Proceedings of the International Symposium on Automation and Robotics in Construction (IAARC), 36th International Symposium on Automation and Robotics in Construction, International Association for Automation and Robotics in Construction (IAARC), Banff, Canada, pp. 862-869.
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© 2019 International Association for Automation and Robotics in Construction I.A.A.R.C. All rights reserved. Additive Manufacturing (AM), also known as 3D printing, is an emerging technology, not only as a prototyping technology, but also to manufacture complete products. Gravity Separation Spirals (GSS) are used in the mining industry to separate slurry into different density components. Currently, spirals are manufactured using moulded polyurethane on fibreglass substructure, or injection moulding. These methods incur significant tooling cost and lead times making them difficult to customise, and they are labour-intensive and can expose workers to hazardous materials. Thus, a 3D printer is under development that can print spirals directly, enabling mass customisation. Furthermore, sensors can be embedded into spirals to measure the operational conditions for predictive maintenance, and to collect data that can improve future manufacturing processes. The localisation of abrasive wear in the GSS is an essential factor in optimising parameters such as suitable material, print thickness, and infill density and thus extend the lifetime and performance of future manufactured spirals. This paper presents the details of a wear sensor, which can be 3D printed directly into the spiral using conductive material. Experimental results show that the sensor can both measure the amount of wear and identify the location of the wear in both the horizontal and vertical axes. Additionally, it is shown that the accuracy can be adjusted according to the requirements by changing the number and spacing of wear lines.

Munasinghe, N, Woods, M, Miles, L & Paul, G 1970, '3-D Printed Strain Sensor for Structural Health Monitoring', 2019 IEEE International Conference on Cybernetics and Intelligent Systems (CIS) and IEEE Conference on Robotics, Automation and Mechatronics (RAM), 2019 IEEE International Conference on Cybernetics and Intelligent Systems (CIS) and IEEE Conference on Robotics, Automation and Mechatronics (RAM), IEEE, Bangkok.
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Additive manufacturing, or 3D printing, is evolving from a technology that can only aid rapid prototyping, to one that can be used to directly manufacture large-scale, real-world equipment. Gravity Separation Spirals (GSS) are vital to the mining industry for separating mineral-rich slurry into its different density components. In order to overcome inherent drawbacks of the traditional mould base manufacturing methods, including significant tooling costs, limited customisation and worker exposure to hazardous materials, a 3D printer is under development to directly print spirals. By embedding small Internet of Things (IoT) sensors inside the GSS, it is possible to remotely determine the operation conditions, predict faults, and use collected data to optimise production output. This work presents a 3D printed strain sensor, which can be directly printed into the GSS. This approach uses a carbon-based conductive filament to print a strain gauge on top of a Polylactic Acid (PLA) base material. Printed sensors have been tested using an Instron E10000 testing machine with an optical extensometer to improve accuracy. Testing was conducted by both loading and unloading conditions to understand the effect of hysteresis. Test results show a near-linear relationship between strain and measured resistance, and show a 6.05% increase in resistance after the test, which indicates minor hysteresis. Moreover, the impact of viscoelastic behaviour is identified, where the resistance response lags the strain. Results from both conductive and non-conductive material show the impact of the conductive carbon upon the tensile strength, which will help to inform future decisions about sensor placement.

Murray, RA, Foy, G & Clemon, L 1970, 'Dimensional comparison of a cold spray additive manufacturing simulation tool', Solid Freeform Fabrication 2019: Proceedings of the 30th Annual International Solid Freeform Fabrication Symposium - An Additive Manufacturing Conference, SFF 2019, Solid Freeform Fabrication Symposium – An Additive Manufacturing Conference, University of Texas, Austin, Texas USA, pp. 1333-1339.
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High-velocity particle spray greatly increases metal additive manufacturing deposition speed over other commercial methods. Accurate prediction and measurement of this process will improve process control. A LightSPEE3D machine fabricated symmetric copper components. On-board software predicts the build geometry (.stl) given the input geometry and the build settings. Assessment of prediction accuracy is needed to enable rapid part design and print setting optimization. White-light 3D-scanning and high-fidelity optical microscopy scans are compared to the simulation and intended 20mm cubes using hausdorf distance: 1. Control-repeated scans: 0.38±0.48mm, max:2.25mm 2. Intended-original vs. scans: 1.42±1.58mm, max:6.72mm 3. Software-predicted vs. scans: 0.44±0.66mm, max:3.97mm Discrepancies up to 6.72mm and asymmetric fabrication artifacts were identified. The reduction in the hausdorf distance for simulation vs intended-original, and larger distance of the simulation compared to control, indicate the simulation tool may enable rapid optimization given over/under spray quantification. Recommendations for reducing asymmetric fabrication artifacts and over/underspray are provided.

Noehring, F, Woestmann, R, Wienzek, T & Deuse, J 1970, 'Socio-Technical Capability Assessment to Support Implementation of Cyber-Physical Production Systems in Line with People and Organization', Advances in Intelligent Systems and Computing, AHFE 2018 International Conference on Human Factors and Systems Interaction, Springer International Publishing, USA, pp. 299-311.
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© Springer International Publishing AG, part of Springer Nature 2019. Cyber-Physical Production Systems (CPPS) enable the intelligent, horizontal and vertical interconnection of people, machines and objects throughout the enterprise in real-time by information and communication technologies providing a basis for increasing transparency and productivity of production processes. However, especially small and medium-sized enterprises with limited resources and personal competencies need support in planning and evaluation of CPPS. Former developments, as the CIM-era, showed that changes in production systems focusing only on technology failed. Due to the interconnection of CPPS, a holistic approach, taking likewise humans, technology and organization into account is necessary. This paper presents requirements as well as an evaluation of existing approaches. Furthermore, this paper presents the approach of a socio-technical capability assessment, enabling companies to evaluate effects of CPPS as well as deriving implementation measures. It concludes with a validation based on a use case of a worker information system.

Park, K, Patten, T & Vincze, M 1970, 'Pix2Pose: Pixel-Wise Coordinate Regression of Objects for 6D Pose Estimation', 2019 IEEE/CVF International Conference on Computer Vision (ICCV), 2019 IEEE/CVF International Conference on Computer Vision (ICCV), IEEE.
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Estimating the 6D pose of objects using only RGB images remains challengingbecause of problems such as occlusion and symmetries. It is also difficult toconstruct 3D models with precise texture without expert knowledge orspecialized scanning devices. To address these problems, we propose a novelpose estimation method, Pix2Pose, that predicts the 3D coordinates of eachobject pixel without textured models. An auto-encoder architecture is designedto estimate the 3D coordinates and expected errors per pixel. These pixel-wisepredictions are then used in multiple stages to form 2D-3D correspondences todirectly compute poses with the PnP algorithm with RANSAC iterations. Ourmethod is robust to occlusion by leveraging recent achievements in generativeadversarial training to precisely recover occluded parts. Furthermore, a novelloss function, the transformer loss, is proposed to handle symmetric objects byguiding predictions to the closest symmetric pose. Evaluations on threedifferent benchmark datasets containing symmetric and occluded objects show ourmethod outperforms the state of the art using only RGB images.

Park, K, Patten, T, Prankl, J & Vincze, M 1970, 'Multi-Task Template Matching for Object Detection, Segmentation and Pose Estimation Using Depth Images', 2019 International Conference on Robotics and Automation (ICRA), 2019 International Conference on Robotics and Automation (ICRA), IEEE.
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Parnell, J & Sommer, R 1970, 'Setting noise objectives for outdoor music festivals in rural locations', Australian Acoustical Society Annual Conference, AAS 2018, pp. 223-231.
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Unwanted music from outdoor events is considered a form of noise pollution which presents a unique set of challenges for regulators when compared to other environmental noise sources. Unlike noise generated by sources such as transport or industry where lower levels are always desirable, there is a minimum level of music below which patron experience will be unacceptable. The challenge for regulators therefore lies in balancing the need for entertainment, against the impacts of outdoor music on the surrounding population. Regulators and organisers of outdoor music festivals in rural environments are generally required to comply with receiver-based noise limits in noise catchments which range from very low backgrounds to those which may have dominant natural or transportation noise. With this in mind, this paper describes the approach undertaken to develop a practical and realistic set of noise objectives for a music festival site on the north coast of NSW, Australia.

Peng, J, Liu, D, Parnell, J & Kessissoglou, N 1970, 'An Australian case study on the estimation of heavy vehicle noise emission on grade', Proceedings of the International Congress on Acoustics, pp. 3735-3739.
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Heavy vehicles are considered the primary determinant of night-time noise disturbance, particularly along principal freight routes. To capture the dynamic influence of heavy vehicles associated with variation in speed and road grade on noise emission, heavy vehicle kinematic variables need to be incorporated within a road traffic noise emission model. These kinematic variables in turn assist with accurate estimation of engine noise and rolling noise. An existing prediction method that considers the driving speed profiles of articulated trucks is the American FHWA TNM road traffic noise model. However, it can only consider a fixed set of speed profiles based on a single heavy vehicle power-to-weight ratio. As such, the model is limited and does not accurately represent the longer and heavier vehicle combinations that dominate the Australian freight haul fleet. In this work, a road traffic noise prediction model which includes the equation of motion for a typical Australian heavy vehicle operating on grade is presented. A case study based on a principal freight route in New South Wales, Australia, is presented to illustrate the predicted variations in engine noise and rolling noise throughout the heavy vehicle's journey.

Piyathilaka, L, Sooriyaarachchi, B, Kodagoda, S & Thiyagarajan, K 1970, 'Capacitive Sensor Based 2D Subsurface Imaging Technology for Non Destructive Evaluation of Building Surfaces', PROCEEDINGS OF THE IEEE 2019 9TH INTERNATIONAL CONFERENCE ON CYBERNETICS AND INTELLIGENT SYSTEMS (CIS) ROBOTICS, AUTOMATION AND MECHATRONICS (RAM) (CIS & RAM 2019), 9th IEEE International Conference on Cybernetics and Intelligent Systems (CIS) / IEEE Conference on Robotics, Automation and Mechatronics (RAM), IEEE, Bangkok, THAILAND, pp. 287-292.
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Understanding the underlying structure of building surfaces like walls andfloors is essential when carrying out building maintenance and modificationwork. To facilitate such work, this paper introduces a capacitive sensor-basedtechnology which can conduct non-destructive evaluation of building surfaces.The novelty of this sensor is that it can generate a real-time 2D subsurfaceimage which can be used to understand structure beneath the top surface. FiniteElement Analysis (FEA) simulations are done to understand the best sensor headconfiguration that gives optimum results. Hardware and software components arecustom-built to facilitate real-time imaging capability. The sensor isvalidated by laboratory tests, which revealed the ability of the proposedcapacitive sensing technology to see through common building materials likewood and concrete. The 2D image generated by the sensor is found to be usefulin understanding the subsurface structure beneath the top surface.

Piyathilaka, L, Sooriyaarachchi, B, Kodagoda, S & Thiyagarajan, K 1970, 'Capacitive Sensor Based 2D Subsurface Imaging Technology for Non-destructive Evaluation of Building Surfaces.', CIS/RAM, IEEE, pp. 287-292.

Pshtiwan Shakor, Shami Nejadi & Gavin Paul 1970, 'An Investigation into the Effects of Deposition Orientation of Material on the Mechanical Behaviours of the Cementitious Powder and Gypsum Powder in Inkjet 3D Printing', Proceedings of the International Symposium on Automation and Robotics in Construction (IAARC), 36th International Symposium on Automation and Robotics in Construction, International Association for Automation and Robotics in Construction (IAARC), Banff, AB, Canada, pp. 42-49.
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© 2019 International Association for Automation and Robotics in Construction I.A.A.R.C. All rights reserved. Three-Dimensional Printing (3DP) is widely used and continues to be rapidly developed and adopted, in several industries, including construction industry. Inkjet 3DP is the approach which offers the most promising and immediate opportunities for integrating the benefits of additive manufacturing technic into the construction field. The ability to readily modify the orientation angle that the printed material is deposited is one of the most advantageous features in a 3DP scaffold compared with conventional methods. The orientation angle has a significant effect on the mechanical behaviours of the printed specimens. Therefore, this paper focuses on printing in different orientations somehow to compare various mechanical properties and to characterise a selection of common construction materials including gypsum (ZP 151) and cement mortar (CP). The optimum strength for the gypsum specimens in compression and flexural strength was observed in the (0° and 90°) and (0°) in the X-Z plane, respectively. According to the experimental results, the compression and flexural strength for ZP 151 are recorded at (11.59±1.18 and 11.78±1.19) MPa and 15.57±0.71 MPa, respectively. Conversely, the highest strength in compression and flexural strength are observed in the (90°) and (0°) degrees in the X-Z plane for the cement mortar, respectively. Moreover, it has been discovered that the compression and flexural strengths for CP are recorded as 19.44±0.11 MPa and 4.06±0.08 MPa, respectively. In addition, the dimensional effect for various w/c ratio has been monitored and examined.

Ragazzon, MRP, Messineo, S, Gravdahl, JT, Harcombe, DM & Ruppert, MG 1970, 'Generalized Lyapunov Demodulator for Amplitude and Phase Estimation by the Internal Model Principle', IFAC-PapersOnLine, Elsevier BV, pp. 247-252.
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Ruppert, MG, Routley, BS, Fleming, AJ, Yong, YK & Fantner, GE 1970, 'Model-based Q Factor Control for Photothermally Excited Microcantilevers', 2019 International Conference on Manipulation, Automation and Robotics at Small Scales (MARSS), 2019 International Conference on Manipulation, Automation and Robotics at Small Scales (MARSS), IEEE.
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Saha, SC, Islam, MS, Rahimi-Gorji, M & Molla, MM 1970, 'Aerosol particle transport and deposition in a CT-scan based mouth-throat model', AIP Conference Proceedings, 8TH BSME INTERNATIONAL CONFERENCE ON THERMAL ENGINEERING, AIP Publishing, Dhaka, Bangladesh.
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© 2019 Author(s). A precise understanding of the aerosol particle transport and deposition (TD) in the realistic mouth-throat model is important for the respiratory health risk assessment and effective delivery of the aerosol medicine to the targeted positions of the lung. A wide range of studies have developed the particle TD framework for both idealized and non-idealized extra-thoracic airways. However, all of the existing in silico and experimental model reports a significant amount of aerosol particles are deposit at the extra-thoracic airways and the existing drug delivery device can deliver only 12 percent of the aerosol drug to the targeted position of the lung. This study aims to increase the efficiency of the targeted drug delivery by developing a realistic particle transport model for CT-Scan based mouth-throat replica. A 3-D realistic mouth-throat model is developed from the CT-Scan DiCom images of a healthy adult cast. High-Quality computational cells are generated for the replica model and the proper grid refinement test has been performed. ANSYS Fluent (19.1) solver is used for the particle TD computation. Tecplot and MATLAB software are used for the post-processing purpose. The numerical results report that the breathing pattern and particle diameter influences the overall particle TD in the mouth-throat model. The numerical results also depict different deposition hot spots for the mouth-throat model, which will eventually help to design a better drug delivery device. The numerical results reported that only 13.67 percent of the 10-μm diameter particles are deposited at the mouth-throat model at 15 lpm flow rate and which indicate that the remaining particles will move to the beyond airways. The present results along with more case studies will develop the understanding of the realistic particle deposition in the extrathoracic airways.

Samavati, M, Palmer, AW, Hill, AJ & Seiler, KM 1970, 'Improvements in plan-driven truck dispatching systems for surface mining', Mining Goes Digital - Proceedings of the 39th international symposium on Application of Computers and Operations Research in the Mineral Industry, APCOM 2019, International Symposium Application of Computers and Operations Research in the Mineral Industry, CRC Press, Wroclaw, Poland, pp. 357-366.
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© 2019 Taylor & Francis Group, London. Truck dispatching systems have been widely used since the 1970s for truck assignments in open pit mines, in order to coordinate material movement from diggers to process plants and stockpiles. Existing commercial solutions are commonly plan-driven systems, which operate by making real-time truck assignments while maintaining conformance to an established haulage allocation plan. Such systems typically comprise programming models to deter-mine the allocation plan as a set of material flow rates. A significant limitation of these methods is that they optimise flow rates only for instantaneous production. These approaches ignore upcoming events and changes in availability and performance, limiting the ability to optimise flows around such events. The method proposed in this paper extends existing approaches by modelling material flows over a future time-horizon, incorporating upcoming events, disrup-tions, and changes in resources. Results are presented comparing an established algorithm with the proposed method, showing improved handling of disruption events.

Schmitt, J, Hahn, F & Deuse, J 1970, 'Practical Framework for Advanced Quality-based Process Control in Interlinked Manufacturing Processes', 2019 IEEE International Conference on Industrial Engineering and Engineering Management (IEEM), 2019 IEEE International Conference on Industrial Engineering and Engineering Management (IEEM), IEEE, Macau.
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As the economic manufacturing of high-quality products becomes an increasingly crucial competitive factor, corresponding quality assurance measures are gaining a growing interest. Even though research interest and industrial demand are both high, there is a large gap between methological approaches and practical applicability that needs to be closed. In this paper we therefore present a practical framework for advanced quality-based process control (AQPC) in interlinked manufacturing processes. Machine learning algorithms are used to predict the expected product quality based on recorded process parameters. That information then serves as an input for the derivation of optimal control decisions. Therefore, we formulate a mathematical optimization model including different options such as order reassignment and process parameter adaption to determine an optimal set of control decisions. We then break down the optimization into a gradual procedure that allows an application-specific integration into manufacturing.

Schreiberhuber, S, Prankl, J, Patten, T & Vincze, M 1970, 'ScalableFusion: High-resolution Mesh-based Real-time 3D Reconstruction', 2019 International Conference on Robotics and Automation (ICRA), 2019 International Conference on Robotics and Automation (ICRA), IEEE.
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Sick, N, Katic, M, Agarwal, R & Cetindamar Kozanoglu, D 1970, 'Operationalising ambidexterity: The role of better management practices in high-variety, low volume manufacturing', PICMET ’19 Conference: Technology Management in the World of Intelligent Systems, Portland, Oregon, USA.

Suchi, M, Patten, T, Fischinger, D & Vincze, M 1970, 'EasyLabel: A Semi-Automatic Pixel-wise Object Annotation Tool for Creating Robotic RGB-D Datasets', 2019 International Conference on Robotics and Automation (ICRA), 2019 International Conference on Robotics and Automation (ICRA), IEEE.
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Developing robot perception systems for recognizing objects in the real-worldrequires computer vision algorithms to be carefully scrutinized with respect tothe expected operating domain. This demands large quantities of ground truthdata to rigorously evaluate the performance of algorithms. This paper presentsthe EasyLabel tool for easily acquiring high quality ground truth annotation ofobjects at the pixel-level in densely cluttered scenes. In a semi-automaticprocess, complex scenes are incrementally built and EasyLabel exploits depthchange to extract precise object masks at each step. We use this tool togenerate the Object Cluttered Indoor Dataset (OCID) that captures diversesettings of objects, background, context, sensor to scene distance, viewpointangle and lighting conditions. OCID is used to perform a systematic comparisonof existing object segmentation methods. The baseline comparison supports theneed for pixel- and object-wise annotation to progress robot vision towardsrealistic applications. This insight reveals the usefulness of EasyLabel andOCID to better understand the challenges that robots face in the real-world. Copyright 20XX IEEE. Personal use of this material is permitted. Permissionfrom IEEE must be obtained for all other uses, in any current or future media,including reprinting/republishing this material for advertising or promotionalpurposes, creating new collective works, for resale or redistribution toservers or lists, or reuse of any copyrighted component of this work in otherworks.

Sukkar, F, Best, G, Yoo, C & Fitch, R 1970, 'Multi-Robot Region-of-Interest Reconstruction with Dec-MCTS', 2019 International Conference on Robotics and Automation (ICRA), 2019 International Conference on Robotics and Automation (ICRA), IEEE, Montreal, QC, Canada, Canada, pp. 9101-9107.
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© 2019 IEEE. We consider the problem of reconstructing regions of interest of a scene using multiple robot arms and RGB-D sensors. This problem is motivated by a variety of applications, such as precision agriculture and infrastructure inspection. A viewpoint evaluation function is presented that exploits predicted observations and the geometry of the scene. A recently proposed non-myopic planning algorithm, Decentralised Monte Carlo tree search, is used to coordinate the actions of the robot arms. Motion planning is performed over a navigation graph that considers the high-dimensional configuration space of the robot arms. Extensive simulated experiments are carried out using real sensor data and then validated on hardware with two robot arms. Our proposed targeted information gain planner is compared to state-of-the-art baselines and outperforms them in every measured metric. The robots quickly observe and accurately detect fruit in a trellis structure, demonstrating the viability of the approach for real-world applications.

Sutjipto, S, Tish, D, Paul, G, Vidal-Calleja, T & Schork, T 1970, 'Towards Visual Feedback Loops for Robot-Controlled Additive Manufacturing', Robotic Fabrication in Architecture, Art and Design 2018, Robotic Fabrication in Architecture, Art and Design, Springer International Publishing, Zurich, pp. 85-97.
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Robotic additive manufacturing methods have enabled the design and fabrication of novel forms and material systems that represent an important step forward for architectural fabrication. However, a common problem in additive manufacturing is to predict and incorporate the dynamic behavior of the material that is the result of the complex confluence of forces and material properties that occur during fabrication. While there have been some approaches towards verification systems, to date most robotic additive manufacturing processes lack verification to ensure deposition accuracy. Inaccuracies, or in some instances critical errors, can occur due to robot dynamics, material self-deflection, material coiling, or timing shifts in the case of multi-material prints. This paper addresses that gap by presenting an approach that uses vision-based sensing systems to assist robotic additive manufacturing processes. Using online image analysis techniques, occupancy maps can be created and updated during the fabrication process to document the actual position of the previously deposited material. This development is an intermediary step towards closed-loop robotic control systems that combine workspace sensing capabilities with decision-making algorithms to adjust toolpaths to correct for errors or inaccuracies if necessary. The occupancy grid map provides a complete representation of the print that can be analyzed to determine various key aspects, such as, print quality, extrusion diameter, adhesion between printed parts, and intersections within the meshes. This valuable quantitative information regarding system robustness can be used to influence the system’s future actions. This approach will help ensure consistent print quality and sound tectonics in robotic additive manufacturing processes, improving on current techniques and extending the possibilities of robotic fabrication in architecture.

Thalhammer, S, Patten, T & Vincze, M 1970, 'SyDPose: Object Detection and Pose Estimation in Cluttered Real-World Depth Images Trained using Only Synthetic Data', 2019 International Conference on 3D Vision (3DV), 2019 International Conference on 3D Vision (3DV), IEEE.
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Ulapane, N, Piyathilaka, L & Kodagoda, S 1970, 'Some Convolution and Scale Transformation Techniques to Enhance GPR Images', 2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA), 2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA), IEEE, Xi'an, China, pp. 1453-1458.
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© 2019 IEEE. Locating reinforcement rods embedded inside concrete wall-like structures, as well as locating subsurface features such as voids, cracks, and interfaces is an essential part of structural health monitoring of concrete infrastructure. The Ground Penetrating Radar (GPR) technique has been commonly used as a means of Non-destructive Testing and Evaluation (NDT E) which suits the purpose. In the recent past, the interest of using GPR to assess the crowns (i.e., top) of concrete sewers has been rising. Moisture is well known to be a challenge for GPR imaging as moisture tends to influence GPR waves. This challenge becomes more common and persistent inside sewers since sewer walls contain considerable surface and subsurface moisture as a result of the humid environment created by the waste water flowing through sewers as well as the bacteria and gas induced acid attacks. Forming a part of sewer condition assessment-related research with the objective of assessing moist concrete, this paper presents some preliminary results which demonstrate how some simple scale transformations and convolution can help in enhancing GPR images in grey-scale. A set of raw GPR signals captured on a moist concrete block inside a laboratory environment is considered. The effect of enhancement is demonstrated against a benchmark image constructed by mapping the raw signals directly onto grey-scale.

Ulapane, N, Wickramanayake, S & Kodagoda, S 1970, 'Pulsed Eddy Current Sensing for Condition Assessment of Reinforced Concrete', 2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA), 2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA), IEEE, China, pp. 1-6.
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© 2019 IEEE. Reinforced concrete (i.e., concrete wall-like structures having steel reinforcement rods embedded within) are commonly available as civil infrastructures. Such concrete structures, especially the walls of sewers, are vulnerable to bacteria and gas induced acid attacks which contribute to deterioration of the concrete and subsequent concrete wall loss. Therefore, quantification of concrete wall loss becomes important in determining the health and structural integrity of concrete walls. An effective strategy that can be formulated to quantify concrete wall loss is, locating a reinforcement rod and determining the thickness of concrete overlaying the rod via Non-destructive Testing and Evaluation (NDT E). Pulsed Eddy Current (PEC) sensing is commonly used for NDT E of metallic structures, including ferromagnetic materials. Since steel reinforcement rods that are commonly embedded in concrete also are ferromagnetic, this paper contributes by presenting experimental results, which suggest the usability of PEC sensing for reinforced concrete assessment, via executing the aforementioned strategy.

Vu, TL, Liu, L, Paul, G & Vidal-Calleja, T 1970, 'Rectangular-shaped object recognition and pose estimation', Australasian Conference on Robotics and Automation, ACRA, Australian Conference on Robotics and Automation, ARAA, Adelaide, pp. 1-9.
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This paper presents a novel solution for rectangular-shaped object pose estimation in the robotic bin-picking problem, using data from a single RGB-D camera collecting point cloud data from a fixed position. The key benefit of the presented framework is its ability to accurately and robustly locate an object position and orientation, which allows for high-precision robotic grasping and placing of such objects in an open-loop motion execution system. Firstly, intelligent grasping surface selection is performed, then Principal Component Analysis is used for pose estimation and finally, rotation averaging is integrated to significantly improve noise-reduction over time. Comparisons between the resulting poses and ones estimated by a traditional Iterative Closest Point technique, have demonstrated the framework’s advantages for pose estimation tasks.

Weibel, J-B, Patten, T & Vincze, M 1970, 'Robust 3D Object Classification by Combining Point Pair Features and Graph Convolution', 2019 International Conference on Robotics and Automation (ICRA), 2019 International Conference on Robotics and Automation (ICRA), IEEE.
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Weisner, K, Knittel, M, Jaitner, T & Deuse, J 1970, 'Increasing Flexibility of Employees in Production Processes Using the Differential Learning Approach – Adaptation and Validation of Motor Learning Theories', Advances in Intelligent Systems and Computing, AHFE 2018 International Conference on Human Factors in Training, Education, and Learning Sciences, Springer International Publishing, USA, pp. 216-225.
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© Springer International Publishing AG, part of Springer Nature 2019. International expanding markets and continuous development of new customer oriented products lead to an increasing product and process variety and complexity as well as shortened product lifecycles. According to these challenges, manufacturing companies have to enhance their process flexibility to remain sustainable competitive. Due to that, employees have to deal with high flexible work processes including continuous change of constellations and objectives. These in turn require a high employee’s flexibility, adaptability and occupational competence as well as new training concepts to enable them. In the academic literature and industrial practice, exists a variety of concepts for employee’s qualification and training. However, these concepts do only partially focus the employee’s occupational competence. Therefore, an innovative learning concept based on motor learning theories was developed and empirically validated. The description of the examination design as well as the result presentation and discussion are subject of the present contribution.

Weßkamp, V, Seckelmann, T, Barthelmey, A, Kaiser, M, Lemmerz, K, Glogowski, P, Kuhlenkötter, B & Deuse, J 1970, 'Development of a sociotechnical planning system for human-robot interaction in assembly systems focusing on small and medium-sized enterprises', Procedia CIRP, CIRP Conference on Manufacturing Systems, Elsevier BV, Ljubljana, Slovenia, pp. 1284-1289.
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© 2019 The Authors. Published by Elsevier Ltd. As part of a research project a holistic planning system for human-robot interaction (HRI) is developed, focusing on the applicability for small and medium-sized enterprises (SMEs). This paper details several important aspects of the planning system, including an easy identification method of suitable processes for HRI. A key element is the work allocation between human workers and robots. The allocation considers e.g. technical feasibility, cycle time as well as personnel deployment and can easily be carried out by SMEs. Based on a simulation, a comprehensible scenario evaluation is developed, focusing primarily on economic aspects but also including ergonomic and safety considerations.

Wickramanayake, S, Thiyagarajan, K, Kodagoda, S & Piyathilaka, L 1970, 'Frequency Sweep Based Sensing Technology for Non-destructive Electrical Resistivity Measurement of Concrete', Proceedings of the International Symposium on Automation and Robotics in Construction (IAARC), 36th International Symposium on Automation and Robotics in Construction, International Association for Automation and Robotics in Construction (IAARC), Canada, pp. 1290-1290.
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© 2019 International Association for Automation and Robotics in Construction I.A.A.R.C. All rights reserved. Electrical resistivity is an important parameter to be monitored for the conditional assessment and health monitoring of aging and new concrete infrastructure. In this paper, we report the design and development of a frequency sweep based sensing technology for non-destructive electrical resistivity measurement of concrete. Firstly, a sensing system prototype was developed based on the Wenner probe arrangement for the electrical resistivity measurements. This system operates by integrating three major units namely current injection unit, sensing unit and microcontroller unit. Those units govern the overall operations of the sensing system. Secondly, the measurements from the developed unit were compared with the measurements of the commercially available device at set conditions. This experimentation evaluated the measurement performance and demonstrated the effectiveness of the developed sensor prototype. Finally, the influence of rebar and the effect of frequency on the electrical measurements were studied through laboratory experimentation on a concrete sample. Experimental results indicated that the electrical resistivity measurements taken at a closer proximity to the rebar had its influence than the measurements taken away from the rebar in the ideal set condition. Also, the increase in electrical resistivity to the increase in frequency was observed, and then the measurements show lesser variations to higher frequency inputs.

Williams, P, Kirby, R & Hill, J 1970, 'Numerical method for prediction of duct break out sound power', Proceedings of Meetings on Acoustics, 178th Meeting of the Acoustical Society of America, ASA, p. 022001.
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The acoustic design of duct systems requires consideration of both the noise propagating within a duct and also of the noise transmitted out through the duct walls into the environment. Control of this breakout noise can form a significant part of a noise control solution, and so understanding this phenomenon can lead to reduced material use. The breakout noise is investigated here using coupled structural-acoustic finite element models. Propagation along a waveguide with constant cross section is represented using a modal expansion of the acoustic pressure in the fluid and displacement in the duct walls. The free-field external environment requires an outer boundary condition, and for this purpose, a perfectly matched layer is applied at some distance from the elastic walls. The finite length of the waveguide is then enforced by coupling the fields to separate infinite length inlet and outlet ducts by the mode matching method. Transmitted power from the finite length duct is investigated when a noise source is placed in the inlet.

Yu, H, Lu, W & Liu, D 1970, 'A Unified Closed-Loop Motion Planning Approach For An I-AUV In Cluttered Environment With Localization Uncertainty', 2019 International Conference on Robotics and Automation (ICRA), 2019 International Conference on Robotics and Automation (ICRA), IEEE, Montreal, CA, pp. 4646-4652.
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© 2019 IEEE. This paper presents a unified motion planning approach for an Intervention Autonomous Underwater Vehicle (I-AUV) in a cluttered environment with localization uncertainty. With the uncertainty being propagated by an information filter, a trajectory optimization problem closed by a Linear-Quadratic-Gaussian controller is formulated for a coupled design of optimal trajectory, localization, and control. Due to the presence of obstacles or complexity of the cluttered environment, a set of feasible initial I-AUV trajectories covering multiple homotopy classes are required by optimization solvers. Parameterized through polynomials, the initial base trajectories are from solving quasi-quadratic optimization problems that are linearly constrained by waypoints from RRTconnect, while the initial trajectories of the manipulator are generated by a null space saturation controller. Simulations on an I-AUV with a 3 DOF manipulator in cluttered underwater environments demonstrated that initial trajectories are generated efficiently and that optimal and collision-free I-AUV trajectories with low state uncertainty are obtained.

Yu, J, Nerse, C, Lee, G, Wang, S & Kyoung-Jin, C 1970, 'Mass production applicable locally resonant metamaterials for NVH applications', Proceedings of the 26th International Congress on Sound and Vibration, ICSV 2019.
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Locally resonant metamaterials have emerged as effective solutions for several types of NVH problems over the last few years, since they offer better performance of noise and vibration reduction than other NVH solutions. However, there have not been many cases that extend to the industrial applications, due to limitations which are often linked with design requirements, such as robustness, lightness and durability. In this paper, the authors propose a novel structural design which is feasible for mass production of locally resonant metamaterial that improves the productivity for industrial application. The proposed structure is made of metal insert injection molding. It enables mass production with insert injection and effectively joins plastic with metal. The manufactured model is applied on a thin plate structure, and experimentally verified. It is observed that the proposed structure effectively reduces the noise and vibration at the target frequency band, and is relatively superior to other vibration treatments such as deadeners. So, the proposed structure of locally resonant metamaterial is expected to be applicable to various industrial fields such as automobiles and home appliances

Zhao, S, Qiu, X, Burnett, I, Rigby, M & Lele, A 1970, 'GMAW metal transfer mode identification from welding sound', Australian Acoustical Society Annual Conference, AAS 2018, Australian Acoustical Society, Australian Acoustical Society, Adelaide, Australia,, pp. 482-491.
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Gas Metal Arc Welding (GMAW) is an arc welding process that forms an electric arc between a consumable electrode and the base metal with a shielding gas to protect the arc. In GMAW, there are various metal transfer modes such as the short circuit mode, the globular mode, the spray mode, and the rotational transfer mode, which show different arc stabilities, weld pool penetrations and spatter production. Identifying the metal transfer mode is critical for process monitoring and quality control of GMAW. In this paper, a m ethod for metal transfer mode identification from the welding sound is presented. A recorder mounted on the welder helmet is used to record the sound signals generated by GMAW under different metal transfer modes, which are analysed in both time and frequency domains. New psychoacoustic parameters based on the auditory perception of an expert welder are extracted to distinguish the metal transfer modes. The Gaussian Mixture Model (GMM) is utilised to identify the metal transfer mode from the welding sound signals and a 10-fold cross validation shows 90% recognition accuracy.

Zhao, S, Qiu, X, Burnett, I, Rigby, M & Lele, A 1970, 'Statistical characteristics of gas metal arc welding (GMAW) sound', Proceedings of the International Congress on Acoustics, Internatioanal Congress on Acoustics, EAA, Achen, Germany, pp. 7594-7601.
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Gas Metal Arc Welding (GMAW) is an arc welding process to join two or more metal materials through fusion, where an electric arc is formed between a consumable electrode and the base metal. It has been reported that expert GMAW welders can direct the welding arc type based on the welding sound, and psychoacoustic experiments show that the welding performance is significantly degraded without the acoustic feedback to the welders. In addition, identifying the metal transfer mode based on the welding sound is critical for automatic GMAW process monitoring, quality control and a training pathway for competency. However, the research on the generation and characteristics of the welding sound is still rare. In this paper, the welding sound is measured simultaneously with the welding current at different metal transfer modes to investigate the unique characteristics of welding sound. The welding sound consists of many impulses corresponding to the current leap. The envelope of the impulse responses is estimated based on the sound pressure signal for statistical analysis. It is found that the probability density function of the peak sound pressure, impulse interval and event duration can be well modelled by the Burr distribution. The findings can be used to classify the metal transfer mode from its welding sound.

Zhu, H, Leighton, B, Chen, Y, Ke, X, Liu, S & Zhao, L 1970, 'Indoor Navigation System Using the Fetch Robot', Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), International Conference on Intelligent Robotics and Applications, Springer International Publishing, Shenyang, China, pp. 686-696.
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© 2019, Springer Nature Switzerland AG. In this paper, we present a navigation system, including off-line mapping and on-line localization, for the Fetch robot in an indoor environment using Cartographer. This framework aims to build a practical, robust, and accurate Robot Operating System (ROS) package for the Fetch robot. Firstly, using Cartographer and the fusion of data from a laser scan and RGB-D camera, a two-dimensional (2D) off-line map is built. Then, the Adaptive Monte Carlo Localization (AMCL) ROS package is used to perform on-line localization. We use a simulation to validate this method of mapping and localization, then demonstrate our method live on the Fetch robot. A video about the simulation and experiment is shown in https://youtu.be/oOvxTOowe34.

Best, G 2019, 'Planning algorithms for multi-robot active perception'.

Eager, D & Hossain, MI 2019, 'Forces on greyhounds as they negotiate bends'.

Eager, D & Hossain, MI 2019, 'Greyhound safety and welfare - A preliminary review of the Angle Park track'.
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Presentation to the GRSA Board

Lee, JJH, Yoo, C, Anstee, S & Fitch, R 2019, 'Efficient Optimal Planning in non-FIFO Time-Dependent Flow Fields', arXiv.
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We propose an algorithm for solving the time-dependent shortest path problem in flow fields where the FIFO (first-in-first-out) assumption is violated. This problem variant is important for autonomous vehicles in the ocean, for example, that cannot arbitrarily hover in a fixed position and that are strongly influenced by time-varying ocean currents. Although polynomial-time solutions are available for discrete-time problems, the continuous-time non-FIFO case is NP-hard with no known relevant special cases. Our main result is to show that this problem can be solved in polynomial time if the edge travel time functions are piecewise-constant, agreeing with existing worst-case bounds for FIFO problems with restricted slopes. We present a minimum-time algorithm for graphs that allows for paths with finite-length cycles, and then embed this algorithm within an asymptotically optimal sampling-based framework to find time-optimal paths in flows. The algorithm relies on an efficient data structure to represent and manipulate piecewise-constant functions and is straightforward to implement. We illustrate the behaviour of the algorithm in an example based on a common ocean vortex model in addition to simpler graph-based examples.

Lee, KMB, Yoo, C, Hollings, B, Anstee, S, Huang, S & Fitch, R 2019, 'Online Estimation of Ocean Current from Sparse GPS Data for Underwater Vehicles', arXiv.

Ma, H, Wang, Y, Tang, L, Kodagoda, S & Xiong, R 2019, 'Towards navigation without precise localization: Weakly supervised learning of goal-directed navigation cost map'.

Ma, H, Wang, Y, Xiong, R, Kodagoda, S & Luo, Q 2019, 'Weakly-Supervised Road Affordances Inference and Learning in Scenes without Traffic Signs'.

Ma, H, Wang, Y, Xiong, R, Kodagoda, S & Tang, L 2019, 'DeepGoal: Learning to Drive with driving intention from Human Control Demonstration'.

Munasinghe, N & Paul, G 2019, 'Advanced Manufacturing of Spirals for Mineral Separation with Integrated Smart Sensing'.
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Gravity Separation Spirals (GSS) are vital to the mining industry for separating mineral-rich slurry into its different density components. The slurry is pumped to the top and, then the spiral slope naturally helps separate the slurry due to the different particle density. Spiral profile can be slightly varied for every customer, depending on the mineral they separate. The research project is focused on developing a 3D printer to print GSS, which can avoid the drawbacks inherent to the traditional GSS manufacturing process. Another objective of this project is to embed sensors into the 3D-printed GSS for remotely monitor the operational conditions, fault diagnosis, and predictive maintenance. 3D printed sensors are being developed instead of embedding conventional sensors where possible since they are low-cost and can be integrated into the large build volume of the structural material without compromising the mechanical integrity of the object.

Piyathilaka, L & Kodagoda, S 2019, 'Understanding Human Context in 3D Scenes by Learning Spatial Affordances with Virtual Skeleton Models'.

Wang, K, Ruppert, MG, Manzie, C, Nesic, D & Yong, YK 2019, 'Adaptive Scan for Atomic Force Microscopy Based on Online Optimisation: Theory and Experiment'.

Weibel, J-B, Patten, T & Vincze, M 2019, 'Addressing the Sim2Real Gap in Robotic 3D Object Classification'.

Xiao, T, Qiu, X & Halkon, B 2019, 'Ultra-broadband local active noise control with remote acoustic sensing', arXiv.
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