Research publications

Zeng, C., Jia, W. & He, X.S.2012, 'An Algorithm for Colour-based Natural Scene Text Segmentation' in Masakazu Iwamura, Faisal Shafait (eds), Camera Based Document Analysis and Recognition, Springer Heidelberg Dordrecht London NewYork, Beijing, China,, pp. 58-68.
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Before the step for text recognition, a text image needs to be segmented into foreground containing only the text area and background. In this paper, a method is proposed for segmenting colour natural scene texts which suffer from a wide range of degradations with complex background. A text image is firstly processed by two 3-means clustering operations with different distance measurements. Then, a modified connected component (CC)-based validation method is used to obtain the text area after clustering. Thirdly, a proposed objective segmentation evaluation method is utilised to choose the final segmentation result from the two segmented text images. The proposed method is compared with other existing methods based on the ICDAR2003 public database. Experimental results show the effectiveness of the proposed method.

Tran, C., Hoang, T.D., Ha, Q.P. & Nguyen, H.T.2012, 'Decentralised Model Predictive Control of Time-Varying Splitting Parallel Systems' in Mohammadpour, Javad; Scherer, Carsten W. (eds), Control of Linear Parameter Varying Systems with Applications, Springer-Verlag Berlin / Heidelberg, Berlin/Heidelberg, pp. 217-251.
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This chapter is devoted to the development of a decentralised model predictive control (MPC) strategy for splitting parallel systems that have timevarying and unknown splitting ratios. The large-scale system in consideration consists of several dynamically-coupled modular subsystems. Each subsystem is regulated by a dedicated multivariable controller employing the open-loop MPC algorithms in conjunction with stability constraints. The connection topology of the large-scale systems includes serial, parallel and recirculated configurations. The solution to splitting parallel systems in this chapter is not only an alternative to the hybrid approach for duty-standby modes, but also a novel approach that accommodates the concurrent operations of splitting parallel systems. The effectiveness of this approach rests on the newly introduced asymptotically positive real constraint (APRC) which prescribes an approaching characteristic towards a positive real property of the system under control. The asymptotic attribute of APRC smooths out all significant wind-up actions in the control trajectories. The APRCs are developed into a one-time-step quadratic constraint on the local control vectors, which plays the role of a stability constraint for the decentralised MPC. The recursive feasibility is assured by characterizing the APRC with dynamicmultiplier matrices. Numerical simulations for two typical modular systems in an alumina refinery are provided to illustrate the theoretical results.

Tran, T.C., Ha, Q., Tuan, H. & Nguyen, H.2012, 'Decentralized Model Predictive Control of Time-varying Splitting Parallel Systems' in Mohammadpour, Javad; Scherer, Carsten W. (eds), Control of Linear Parameter Varying Systems with Applications, Springer, Houston, Stuttgart, pp. 217-251.

Lowe, D.B., Conlon, S., Murray, S.J., Weber, L., Nageswaran, W., De La Villefromoy, M.J., Lindsay, E., Nafalski, A. & Tang, T.2012, 'LabShare: Towards Cross-Institutional Laboratory Sharing' in Azad, Abul; Auer, Michael; Harward, Judson (eds), Internet Accessible Remote Laboratories: Scalable E-Learning Tools for Engineering and Science Disciplines, IGI Global, Hershey PA, USA, pp. 453-467.
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Conventional undergraduate teaching laboratories are valuable in terms of their contributions to students learning but are generally costly to develop and maintain and often have extremely low overall utilization rates. These issues can be addressed through cross-institutional sharing of laboratories. This is, however, limited by the overarching requirement that students are physically co-located with the laboratory apparatus. In this chapter we will describe the nature of the challenges with regard to cross-institutional sharing and the potential benefits that can be achieved if a solution can be found. A possible solution is the use of remote laboratories that can be accessed across the internet with a suitable model for laboratory sharing that promotes both institutional and individual engagement. We describe the characteristics that such a model should have and show how the Labshare project is providing a nation-wide model within the Australian Higher Education context.

Yeh, W., Cao, L. & Jin, J.2012, 'A Cellular Automata Hybrid Quasi-random Monte Carlo Simulation for Estimating the One-to-all Reliability of Acyclic Multistate Information Networks', International Journal Of Innovative Computing Information And Control, vol. 8, no. 3(B), pp. 2001-2014.
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Many real-world systems (such as cellular telephones and ransportation) are acyclic multi-state information networks (AMIN). These networks are composed of multi-state nodes, with different states determined by a set of nodes that receive a signal directly from these multi-state nodes, without satisfying the conservation law. Evaluating the AMIN reliability arises at the design and exploitation stage of many types of technical systems. However, existing analytical methods fail to estimate AMIN reliability in a realistic time frame, even for smaller-sized AMINs. Hence, the main purpose of this article is to present a cellular automata hybrid quasi-Monte Carlo simulation (CA-HMC) by combining cellular automata (CA, to rapidly determine network states), pseudo-random sequences (PRS, to obtain the exibility of the network) and quasi-random sequences (QRS, to improve the accuracy) to obtain a high-quality estimation of AMIN reliability in order to improve the calculation efficiency. We use one benchmark example from well-known algorithms in literature to show the utility and performance of the proposed CA-HMC simulation when evaluating the one-to-all AMIN reliability.

Luo, Z., Zhang, N., Ji, J. & Wu, T.2012, 'A meshfree level-set method for topological shape optimization of compliant multiphysics actuators', Computer Methods in Applied Mechanics and Engineering, vol. 223-224, pp. 133-152.
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This paper proposes a topology optimization method for compliant multiphysics actuators of geometrically nonlinear structures using meshfree Galerkin weak-forms and level set methods. The design boundary is implicitly represented as the zero level set of a higher-dimensional level set function, leading to a level set model capable of handling complex shape and topological changes with flexibilities. A family of compactly supported radial basis functions (CSRBFs) is firstly used to interpolate the level set function of Lipschitz continuity, and then augmented to construct the shape function for meshless approximation by satisfying basic requirements, in particular the predetermined consistency and the Kronecker delta function property. A meshless Galerkin method (MGM) with global weak-forms is established to implement the discretization of the state equations. The design of actuators is transformed into an easier size optimization from a more difficult shape and topology optimization. The design boundary evolution is just a question of advancing the discrete level set function in time by updating the design variables of the size optimization. Compared to most conventional level set methods, the proposed meshless level set method is able to implement the free moving boundary discontinuities without remeshing, and unify two different numerical procedures in propagating the discrete level set function (e.g. Eulerian grid) and approximating the state equation (e.g. Lagrangian mesh), respectively. This method can also avoid numerical difficulties in solving a series of complicate Hamilton-Jacobi partial differential equations (PDEs) with explicit time schemes. Two typical numerical examples are used to demonstrate the effectiveness of the proposed method.

Luo, Z. & Zhang, N.2012, 'A multi-criteria topology optimization for systematic design of compliant mechanisms', Computers, Materials, & Continua, vol. 28, pp. 27-56.
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This paper attempts to present a new multi-criteria topological optimization methodology for the systematic design of compliant micro-mechanisms. Instead of employing only the strain energy (SE) or the functional specifications such as mechanical efficiency (ME), in this study an alternative formulation representing multiple design requirements is included in the optimization to describe the performance of compliant mechanisms. In most conventional designs, SE is used to only measure the design requirement from the point of view of structures, while ME is usually applied to describe the mechanical performance of mechanisms. However, the design of a compliant mechanism is required to comprehensively consider both the structural and mechanical performance quantities. Displacement, material usage and dynamic response are imposed as three external constraints to narrow the searching domain. In doing so, the multi-criteria optimization problem involving the SE and ME can reasonably embody the mechanical structural characteristics of compliant mechanisms. A sequential convex programming, the method of moving asymptotes (MMA), is applied to solve the topological optimization problem, which can not only ensure numerical accuracy but also both the monotonous and non-monotonous structural behaviors. SIMP model (solid isotropic material with penalization) is used to indicate the dependence of elastic modulus upon regularized element densities. Several typical numerical examples are used to demonstrate the effectiveness of the proposed methodology, and the prototype of a resulting mechanism has also been manufactured to validate the design of the compliant mechanism.

Yeh, W., Ho, H., Chen, Y. & Yeh, Y.2012, 'A New Algorithm for Finding All Minimal Cuts in Modified Networks', International Journal Of Innovative Computing Information And Control, vol. 8, no. 1(A), pp. 419-430.
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Evaluating network reliability is an important topic in the planning, designing and control of network systems. Modications are common for network expansion or reinforcement evaluation and planning. A modied network is an updated network after inserting a branch string (a special path) between two nodes in the original network. The problem of searching all minimal cuts (MCs) in a modied network is discussed and solved in this study. The proposed algorithm is easier to understand and implement than the existing known related algorithms. The accuracy of the proposed algorithm will be validated. The computational complexity of the proposed algorithm is analyzed and compared with the existing best-known methods. One benchmark example is illustrated to show how to nd all MCs in a modied network using the information of all the MCs in the corresponding original network.

Valipour Goudarzi, H. & Bradford, M.A.2012, 'A new shape function for tapered three-dimensional beams with flexible connections', Journal Of Constructional Steel Research, vol. 70, pp. 43-50.
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The principle of virtual force and concept of force interpolation is employed to develop a systematic method for deriving the shape functions for the tapered three-dimensional frame element with flexible end connections. These shape functions can be used to calculate the stiffness, geometric stiffness and consistent mass matrices of the tapered frame element with flexible connections. The formulation adopts the Eulera??Bernoulli hypothesis and linear elastic material behaviour, with local buckling effects being ignored. The formulation is verified by some numerical examples on the buckling load and dynamic frequency analysis of tapered beams with rigid and flexible connections. It is shown that the systematic method developed in the paper is mostly superior in its efficiency compared with elements based on Hermitian interpolation functions.

Kang, Z., Xu, K. & Luo, Z.2012, 'A numerical study on nonlinear vibration of an inclined cable coupled with the deck in cable-stayed bridges', Journal of Vibration and Control, vol. 18, no. 3, pp. 404-416.
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The mechanism and the characteristics of the cable-deck coupled nonlinear vibration in a cable-stayed bridge are studied using numerical methods. A simple three-degrees-of-freedom (d.f.) model, with one independent d.f. for modeling the bridge deck movement, is proposed for describing the nonlinear interactions between the in-plane/out-of-plane vibration of the cable and the oscillation of the bridge deck. The governing equations are discretized with the Galerkin method and then solved with a numerical time integration algorithm. It is pointed out that the periodic variation of cable tension caused by vibration of a bridge deck will lead to the parametric resonance of the stay cable under certain tuning conditions. Numerical results also confirm that energy transfer between different vibration modes and beating phenomenon of the cable-deck vibration may be exhibited in the case of parametric resonance.

Luo, Z., Zhang, N. & Wang, Y.2012, 'A physically meaningful level set method for topology optimization of structures', CMES: Computer Modeling in Engineering & Sciences, vol. 2055, no. 1, pp. 1-24.
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This paper aims to present a physically meaningful level set method for shape and topology optimization of structures. Compared to the conventional level set method which represents the design boundary as the zero level set, in this study the boundary is embedded into non-zero constant level sets of the level set function, to implicitly implement shape fidelity and topology changes in time via the propagation of the discrete level set function. A point-wise nodal density field, non-negative and value-bounded, is used to parameterize the level set function via the compactly supported radial basis functions (CSRBFs) at a uniformly defined set of knots. The set of densities are used to interpolate practical material properties in finite element approximation via the standard Lagrangian shape function. CSRBFs knots are supposed to be consistent with finite element nodes only for the sake of numerical simplicity. By doing so, the discrete values of the level set function are assigned with practical material properties via the physically meaningful interpolation. The original more difficult shape and topology optimization of the Hamilton-Jacobi partial differential equations (PDEs) is transformed to a relatively easier size optimization of the nodal densities, to which more efficient optimization algorithms can be directly applied. In this way, the dynamic motion of the design boundary is just a question of transporting the discrete level set function until the optimal criteria of the structure is satisfied. Two widely studied examples are applied to demonstrate the effectiveness of the proposed method.

Dorrell, D.G., Hsieh, M. & Knight, A.M.2012, 'Alternative Rotor Designs for High Performance Brushless Permanent Magnet Machines for Hybrid Electric Vehicles', IEEE Transactions On Magnetics, vol. 48, no. 2, pp. 835-838.

Zhang, Y., Zhu, J., Zhao, Z., Xu, W. & Dorrell, D.G.2012, 'An Improved Direct Torque Control for Three-Level Inverter-Fed Induction Motor Sensorless Drive', IEEE Transactions On Power Electronics, vol. 27, no. 3, pp. 1502-1513.

Zhao, Y., Gao, B., Shon, H., Wang, Y., Kim, J.H., Yue, Q. & Bo, X.Y.2012, 'Anionic polymer compound bioflocculant as a coagulant aid with aluminum sulfate and titanium tetrachloride', Bioresource Technology, vol. 108, pp. 45-54.
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The objectives of this study are to investigate the impacts of anionic polymer compound bioflocculant (CBF) as a coagulant aid on coagulation performance and floc characteristics with titanium tetrachloride (TiCl4) and aluminum sulfate (Al2(SO4)3). The effect of dosing sequence was also investigated. Floc size, breakage, regrowth and floc fractal dimension were examined using a laser diffraction instrument. The results showed that CBF with TiCl4 or Al2(SO4)3 coagulants exhibited synergistic effects by promoting dissolved organic carbon (DOC) removal. For both TiCl4 and Al2(SO4)3, the floc recoverability was improved by CBF addition, and the flocs formed by TiCl4 and the corresponding dual-coagulants showed weaker recovery ability than those by Al2(SO4)3 and the corresponding dual-coagulants. Fractal dimension analysis demonstrated that the floc fractal dimension values increased with the increasing coagulant dose. The effect of CBF on fractal dimension of the flocs generated by TiCl4 was different from that of Al2(SO4)3.

Phuntsho, S., Shon, H., Majeed, T., El Saliby, I., Vigneswaran, S., Kandasamy, J.K., Hong, S. & Lee, S.2012, 'Blended Fertilizers as Draw Solutions for Fertilizer-Drawn Forward Osmosis Desalination', Environmental Science & Technology, vol. 46, pp. 4567-4575.
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In fertilizer-drawn forward osmosis (FDFO) desalination, the final nutrient concentration (nitrogen, phosphorus, potassium (NPK)) in the product water is essential for direct fertigation and to avoid over fertilization. Our study with 11 selected fertilizers indicate that blending of two or more single fertilizers as draw solution (DS) can achieve significantly lower nutrient concentration in the FDFO product water rather than using single fertilizer alone. For example, blending KCl and NH4H2PO4 as DS can result in 0.61/1.35/1.70 g/L of N/P/K, which is comparatively lower than using them individually as DS. The nutrient composition and concentration in the final FDFO product water can also be adjusted by selecting low nutrient fertilizers containing complementary nutrients and in different ratios to produce prescription mixtures. However, blending fertilizers generally resulted in slightly reduced bulk osmotic pressure and water flux in comparison to the sum of the osmotic pressures and water fluxes of the two individual DSs as used alone. The performance ratio or PR (ratio of actual water flux to theoretical water flux) of blended fertilizer DS was observed to be between the PR of the two fertilizer solutions tested individually. In some cases, such as urea, blending also resulted in significant reduction in N nutrient loss by reverse diffusion in presence of other fertilizer species.

Zhao, Y., Gao, B., Wang, Y., Shon, H., Bo, X.Y. & Yue, Q.2012, 'Coagulation performance and floc characteristics with polyaluminum chloride using sodium alginate as coagulant aid: A preliminary assessment', Chemical Engineering Journal, vol. 183, pp. 387-394.
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The effect of sodium alginate (SA) on coagulation performance and floc characteristics with polyaluminum chloride (PAC) was evaluated in synthetic humic acid-kaolin water treatment. Coagulation performance and floc characteristics of PAC were investigated for comparison. The results showed that PAC plus SA exhibited certain synergistic effect on DOC (dissolved organic carbon) and turbidity removal. DOC removal was more enhanced by SA at low PAC doses than at higher ones, while turbidity removal was enhanced when PAC doses were larger than 1.5 mg/L. The growth, breakage, regrowth and fractal nature of flocs were investigated using Mastersizer 2000, with the results suggesting that the aggregated flocs after PAC-SA (PAC dosed first) flocculation showed faster growth rate and with larger floc size compared with the flocs formed by PAC. Besides, PAC-SA gave the flocs with more open structure but better recovery ability after floc breakage compared with PAC.

Dehestani, D., Madadnia, J., Koosha, H. & Eftekhari, F.2012, 'Comprehensive Analysis for Air Supply Fan Faults Based on HVAC Mathematical Model', Advanced Materials Research, vol. 452-453, pp. 460-468.
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Due to the growing demand on high efficient heat ventilation and air conditioning (HVAC) systems, how to improve the efficiency of HVAC system regarding reduces energy consumption of system has become one of the critical issues. Reports indicate that efficiency and availability are heavily dependent upon high reliability and maintainability. Recently, the concept of e-maintenance has been introduced to reduce the cost of maintenance. In e-maintenance systems, the fault detection and isolation (FDI) system plays a crucial role for identifying failures. Finding healthy HVAC source as the reference for health monitoring is the main aim in this area. To dispel this concern a comprehensive transient model of heat ventilation and air conditioning (HVAC) systems is developed in this study. The transient model equations can be solved efficiently using MATLAB coding and simulation technique. Our proposed model is validated against real HVAC system regarding different parts of HVAC. The developed model in this study can be used for a pre tuning of control system and put to good use for fault detection and isolation in order to accomplish high-quality health monitoring and result in energy saving. Fan supply consider as faulty device of HVAC system with six fault type. A sensitivity analysis based on evaluated model shows us three features are sensitive to all faults type and three auxiliary features are sensitive to some faults. The magnitude and trait of features are a good potential for automatic fault tolerant system based on machine learning systems.

Kusakunniran, W., Wu, Q., Zhang, J. & Li, H.2012, 'Cross-view and multi-view gait recognitions based on view transformation model using multi-layer perceptron', Pattern Recognition Letters, vol. 33, pp. 882-889.
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Gait has been shown to be an efficient biometric feature for human identification at a distance. However, performance of gait recognition can be affected by view variation. This leads to a consequent difficulty of cross-view gait recognition. A novel method is proposed to solve the above difficulty by using view transformation model (VTM). VTM is constructed based on regression processes by adopting multi-layer perceptron (MLP) as a regression tool. VTM estimates gait feature from one view using a well selected region of interest (ROI) on gait feature from another view. Thus, trained VTMs can normalize gait features from across views into the same view before gait similarity is measured. Moreover, this paper proposes a new multi-view gait recognition which estimates gait feature on one view using selected gait features from several other views. Extensive experimental results demonstrate that the proposed method significantly outperforms other baseline methods in literature for both cross-view and multi-view gait recognitions. In our experiments, particularly, average accuracies of 99%, 98% and 93% are achieved for multiple views gait recognition by using 5 cameras, 4 cameras and 3 cameras respectively.

Aslani, F., Nejadi, S.2012, 'Cyclic constitutive model for high-strength concrete confined by ultra-high-strength and normal-strength transverse reinforcements', Australian Journal of Structural Engineering, vol. 12, no. 2, pp. 59-72.
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In this paper, a cyclic constitutive model is developed for high-strength concrete (HSC) confined by ultra-high-strength and normal-strength transverse reinforcements (UHSTR and NSTR), with the intention of providing efficient modeling for the member and structural behavior of HSC in seismic regions. The model for HSC subjected to monotonic and cyclic loading, comprises four components; an envelope curve (for monotonic and cyclic loading), an unloading curve, a reloading curve, and a tensile unloading curve. It explicitly accounts for the effects of concrete compressive strength, volumetric ratio of transverse reinforcement, yield strength of ties, tie spacing, and tie pattern. Comparisons with test results showed that the proposed model provides a good fit to a wide range of experimental results.

Madadnia, J., Kala, D., Pillai, D. & Koosha, H.2012, 'Design, Build and Testing of a Noise-free Twin Shaft Co-Axial Wind Turbine For UTS Buildings', Advanced Materials Research, vol. 452-453, pp. 1089-1093.
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Management and control of noise pollution in wind turbines are important to integrate wind turbines in building and urban areas. A scaled model of a horizontal-co-axial wind turbine was designed, built and tested in the wind tunnel of University of Technology Sydney (UTS) and its characteristics and aerodynamic-noise emissions were analyzed. The noise reduction capability of the horizontal-twin-shaft wind turbines was compared with wind turbines with the conical entry nozzle (stator), duct-shroud-envelop and vertical shafts. Air velocity, shaft rpm, electric-power generation, noise frequency and amplitude were measured. It was found that up to 15% reduction in the amplitude (dB) of noise emisit from twin shaft wind turbine compared to the single shaft bench mark turbine. The noise analysis performed as a result of these experiments may be used in the design and selection of a building integrated horizontal axis wind turbine for applications at UTS buildings.

Yeh, Y., Hsieh, M. & Dorrell, D.G.2012, 'Different Arrangements for Dual-Rotor Dual-Output Radial-Flux Motors', IEEE Transactions On Industry Applications, vol. 48, no. 2, pp. 612-622.

Nuryani, N., Ling, S.S. & Nguyen, H.T.2012, 'Electrocardiographic signals and swarm-based support vector machine for hypoglycemia detection', Annals Of Biomedical Engineering, vol. 40, no. 4, pp. 934-945.
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Cardiac arrhythmia relating to hypoglycemia is suggested as a cause of death in diabetic patients. This article introduces electrocardiographic (ECG) parameters for artificially induced hypoglycemia detection. In addition, a hybrid technique of swarm-based support vector machine (SVM) is introduced for hypoglycemia detection using the ECG parameters as inputs. In this technique, a particle swarm optimization (PSO) is proposed to optimize the SVM to detect hypoglycemia. In an experiment using medical data of patients with Type 1 diabetes, the introduced ECG parameters show significant contributions to the performance of the hypoglycemia detection and the proposed detection technique performs well in terms of sensitivity and specificity.

Walker, P.D. & Zhang, N.2012, 'Engagement and control of synchroniser mechanisms in dual clutch transmissions', Mechanical Systems and Signal Processing, vol. 26, no. 1, pp. 320-332.
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The study of synchroniser engagements in dual clutch transmissions is undertaken in this paper, identifying limitations to the repeatability of actuation, demonstrating one popular solution for positive synchroniser control and offering an alternate engagement tool. Principally, high wet clutch drag and the synchroniser design have lead to detrimental alignments conditions, where indexing chamfers on sleeve and target gear delay engagement of the mechanism and lead to potential sleeve block out. This paper focuses on the investigation of different control methods for overcoming these detrimental alignment conditions. The application of a closed loop control method to overcome block out related engagements is studied, and, for comparison, a novel engagement tool for overriding all chamfer alignment conditions is introduced and evaluated. Results have demonstrated that both techniques have some limitations, with the novel tool being capable of providing direct control of all chamfer engagements with limited extension of the duration of synchroniser engagements; however, some tuning of mechanism parameters is required for different engagement conditions.

Zahrai, S.M., Abbasi, S., Samali, B. & Vrcelj, Z.2012, 'Experimental investigation of utilizing TLD with baffles in a scaled down 5-story benchmark building', Journal of Fluids and Structures, vol. 28, no. 1, pp. 194-210.
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A tuned liquid damper (TLD) is a special type of auxiliary damping device, which relies on the sloshing of a liquid (water) in a container to counteract the forces acting on the structure. Damping in the TLD is introduced as a result of liquid sloshing and wave breaking. A conventional TLD is generally tuned to the main frequency of the building and is less efficient in other frequencies. Because of this limitation, the TLD is usually used to control the structural response of structures, which could be simulated as a SDOF structure, and mostly due to wind forces. In this paper a new kind of tuned liquid damper with some installed rotatable baffles is studied experimentally. The main idea behind installing such baffles is to compensate the effects of probable mistuning of the TLD and also it is an effort toward making the TLD more controllable, i.e. a semi-active damper. Response of a five story benchmark building was utilized to investigate the contributions of these baffles on efficiency of tuned liquid damper under dynamic and earthquake excitations. By observing the performance of TLD with baffles, the study investigates the influence of a number of parameters, include the following: baffles angles, frequency ratio, mass ratio and especially the effects of probable mistuning with changing the depth of water and orientation of baffles. The damping ratios of the building for a range of baffles angles were evaluated using logarithmic decrement technique. The results that are obtained in this paper show that the displacement and acceleration responses of the structure under the free vibration test utilizing the baffles reduced up to 2.5% and 3.9%, respectively, when compared with the case where no baffles are employed. Also the dynamic magnification factor under harmonic excitation reduced up to 2.7% proportional to baffles angles. Damping of the structure equipped with this type of TLD increased in a range of 3.93a??6.38% when compared to the case of using no damper. The displacement and acceleration responses of the building under scaled down earthquakes also decreased up to 24.07% and 27.24%, respectively, with some of the best control results occurring before full closure of baffles.

Madadnia, J., Dagci, P., Lewis, P. & Taskin, T.2012, 'Feasibility of Emerging Technologies Based Cogeneration Systems for University of Technology Sydney', Advanced Materials Research, vol. 452-453, pp. 1084-1088.
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This paper presents an optimum selection of a co-generation system for heat and power generation at University of Technology Sydney, based on technological, environmental, social and economical factors. Five potential cogeneration concepts were developed based on Internal combustion (IC) engines, External combustion engines including Stirling engine, Organic Rankine cycle (ORC), Kalina cycle, and Fuel-cells, and compared. Organic Rankine Module (ORC) is finally selected. The selected cogeneration offers shorter payback period, lower IRRand net-energy savings, lower Co2 emissions, and higher electric-power generation capacity.

Hossain, M.A., Ngo, H., Guo, W. & Nguyen, T.2012, 'Feasibility study of palm oil fruit shells as biosorbent for copper removal from water and wastewater', Bioresource Technology, vol. in Press.
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Palm oil fruit shells were evaluated as a new bioadsorbent to eliminate toxic copper from water and wastewater. Without any chemical treatment, palm oil fruit shells were washed, dried and grounded into powder (<75 I?m) for use in the experiments. Characterization showed mesopore based bioadsorbent was prepared from palm oil fruit shells. The results indicate that the highest Cu removal efficiency was found in an aqueous solution with pH of 6.5. The equilibrium sorption capacity of copper was significantly high (between 28 and 60 mg/g) at room temperature. Nonlinear regression analyses for isotherm models revealed that three-parameter isotherms had a better fit to the experimental data (R 2 > 0.994) than that of two-parameter isotherms. The copper sorption system was heterogeneous as the values of exponents were lying between 0 and 1. The highly correlated pseudo-second-order kinetics model (R 2 > 0.998) ascertained the applicability of copper removal by palm oil fruit shells. A? 2011 Elsevier Ltd.

Cheng, J., Xie, C., Bian, W. & Tao, D.2012, 'Feature fusion for 3D hand gesture recognition by learning a shared hidden space', Pattern Recognition Letters, vol. 33, no. 4, pp. 476-484.
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Hand gesture recognition has been intensively applied in various human?computer interaction (HCI) systems. Different hand gesture recognition methods were developed based on particular features, e.g., gesture trajectories and acceleration signals. However, it has been noticed that the limitation of either features can lead to flaws of a HCI system. In this paper, to overcome the limitations but combine the merits of both features, we propose a novel feature fusion approach for 3D hand gesture recognition. In our approach, gesture trajectories are represented by the intersection numbers with randomly generated line segments on their 2D principal planes, acceleration signals are represented by the coefficients of discrete cosine transformation (DCT). Then, a hidden space shared by the two features is learned by using penalized maximum likelihood estimation (MLE). An iterative algorithm, composed of two steps per iteration, is derived to for this penalized MLE, in which the first step is to solve a standard least square problem and the second step is to solve a Sylvester equation. We tested our hand gesture recognition approach on different hand gesture sets. Results confirm the effectiveness of the feature fusion method.

Keshavarzi, A., Ball, J.E. & Nabavi, H.2012, 'Frequency pattern of turbulent flow and sediment entrainment over ripples using image processing', Hydrology And Earth System Sciences, vol. 16, no. 1, pp. 147-156.
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River channel change and bed scourings are source of major environmental problem for fish and aquatic habitat. The bed form such as ripples and dunes is the result of an interaction between turbulent flow structure and sediment particles at the bed. The structure of turbulent flow over ripples is important to understand initiation of sediment entrainment and its transport. The focus of this study is the measurement and analysis of the dominant bursting events and the flow structure over ripples in the bed of a channel. Two types of ripples with sinusoidal and triangular forms were tested in this study. The velocities of flow over the ripples were measured in three dimensions using an Acoustic Doppler Velocimeter with a sampling rate of 50 Hz. These velocities were measured at different points within the flow depth from the bed and at different longitudinal positions along the flume. A CCD camera was used to capture 1500 sequential images from the bed and to monitor sediment movement at different positions along the bed. Application of image processing technique enabled us to compute the number of entrained and deposited particles over the ripples. From a quadrant decomposition of instantaneous velocity fluctuations close to the bed, it was found that bursting events downstream of the second ripple, in Quadrants 1 and 3, were dominant whereas upstream of the ripple, Quadrants 2 and 4 were dominant. More importantly consideration of these results indicates that the normalized occurrence probabilities of sweep events along the channel are in phase with the bed forms whereas those of ejection events are out of phase with the bed form. Therefore entrainment would be expected to occur upstream and deposition occurs downstream of the ripple. These expectations were confirmed by measurement of entrained and deposited sediment particles from the bed. These above information can be used in practical application for rivers where restoration is required.

Aryal, R., Vigneswaran, S., Loganathan, P., Kandasamy, J.K. & Mohammed, T.M.2012, 'Hydrous iron oxide for removal of inorganic contaminants in simulated stormwater: A batch sorption kinetics study', Korean Journal of Chemical Engineering, vol. 28, no. 8, pp. 1706-1712.
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Urban stormwater runoff, which consists of inorganic and organic contaminants, is a major source of pollutants to receiving waters and therefore they need to be removed. Simultaneous removal of contaminants, Cd2+, Cu2+, Ni2+, Zn2+ (heavy metal cations), and SeO4 2a?? (oxyanion) from a simulated stormwater by a hydrous ferric oxide (HFO) was studied in batch and column sorption experiments. In the batch experiment the rate of sorption of the ions was rapid at the beginning and reached equilibrium in approximately 300 min. The amounts of ions sorbed were proportionate to the respective initial concentration of the ions added to the HFO. Cluster analysis showed that all heavy metals had similar sorption behavior, whereas Se had a distinctly different sorption process. Of the three different kinetic models tested the pseudo-first order kinetic model fitted the data the best. The column experimental results beyond 180 min were consistent with those of the batch experiment that the removal efficiencies of the ions were in proportion to the ion concentration in the feed. Below 180 min, Cu appeared to be preferentially removed than Zn.

Aguirre-Ollinger, G., Colgate, J.E., Peshkin, M. & Goswami, A.2012, 'Inertia Compensation Control of a One-Degree-of-Freedom Exoskeleton for Lower-Limb Assistance: Initial Experiments', IEEE Transactions on Neural Systems and Rehabilitation Engineering, vol. 20, no. 1, pp. 68-77.
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A new method of lower-limb exoskeleton control aimed at improving the agility of leg-swing motion is presented. In the absence of control, an exoskeleton?s mechanism usually hinders agility by adding mechanical impedance to the legs. The uncompensated inertia of the exoskeleton will reduce the natural frequency of leg swing, probably leading to lower step frequency during walking as well as increased metabolic energy consumption. The proposed controller emulates inertia compensation by adding a feedback loop consisting of low-pass filtered angular acceleration multiplied by a negative gain. This gain simulates negative inertia in the low-frequency range. The resulting controller combines two assistive effects: increasing the natural frequency of the lower limbs and performing net work per swing cycle. The controller was tested on a statically mounted exoskeleton that assists knee flexion and extension. Subjects performed movement sequences, first unassisted and then using the exoskeleton, in the context of a computer-based task resembling a race. In the exoskeleton?s baseline state, the frequency of leg swing and the mean angular velocity were consistently reduced. The addition of inertia compensation enabled subjects to recover their normal frequency and increase their selected angular velocity. The work performed by the exoskeleton was evidenced by catch trials in the protocol.

Hong, S., Aryal, R., Vigneswaran, S., Johir, M.H. & Kandasamy, J.K.2012, 'Influence of hydraulic retention time on the nature of foulant organics in a high rate membrane bioreactor', Desalination, vol. 287, no. 1, pp. 116-122.
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The influence of hydraulic retention time (HRT) in a submerged hollow fibre membrane bioreactor was studied by conducting experiments at four different HRTs (4,2, 1.3 and 1 h) at room temperature of 25 A?C. lt was found that a shorter HRT led to a higher development of trans-membrane pressure. The highest sludge cake and pore-blocking resistances of 4.02 x 1011 m-1 and 0.77 x 1011 m-1 respectively were noted for the shortest HRT (of 1 h) application. UV and fluorescence spectroscopy analyses showed that the nature of organics in the biomass and sludge cakes were different. The organic fraction analysis by liquid chromatography with organic carbon detector (LC-OCO) showed a significant amount of biopolymers and a lower amount of humics for longer HRT.

Brown, i., Ionel, D. & Dorrell, D.G.2012, 'Influence of Parallel Paths on Current Regulated Sine-Wave Interior Permanent Magnet Machines with Rotor Eccentricity', IEEE Transactions On Industry Applications, vol. 48, no. 2, pp. 642-652.

Qureshi, M.2012, 'Interoperability of Software Engineering Metamodels', Lecture Notes in Computer Science, vol. 7167, pp. 12-19.
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Several metamodels have been proposed in the software engineering literature recently. For practical usage, it is important to ensure that these metamodels can be used in an interoperable fashion. In this paper we present an approach as a part of our PhD research in the same direction. Our methodology is based on the study of analogous characteristics among metamodels, ontologies and schemas. We have adopted ontology merging and schema matching techniques and apply them to the domain of metamodels to assist in creating interoperable metamodels. This methodology is applied and presented here with an illustrative example in which we show the results of merging two of the OMG metamodels: the Organization Structure Metamodel (OSM) and the Business Process Modelling Notation (BPMN).

Walker, P.D. & Zhang, N.2012, 'Investigation of synchroniser engagement in dual clutch transmission equipped powertrains', Journal Of Sound And Vibration, vol. 331, no. 6, pp. 1398-1412.
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Transient response of a dual clutch transmission (DCT) powertrain to synchroniser mechanism engagements is investigated using a lumped inertia model of the powertrain. Original research integrates lumped inertia powertrain models for the DCT with a detailed synchroniser mechanism model and two separate engine models, comprising of a mean torque model and a harmonic torque model, using torque derived from piston firing. Simulations are used to investigate the synchroniser mechanism engagement process in a previously unscrutinised operating environment. Simulations are performed using both engine torque models, with the mean torque model demonstrates the highly nonlinear nature of synchroniser mechanism engagement, and the powertrain response to the engagement process. Through the introduction of harmonic engine torques, additional excitation is present in the mechanism during engagement, and increased vibration of the synchroniser sleeve results. The impact of vibrations is particularly important to the increased wear of indexing chamfer contact surfaces.

Walker, A., McBride, T.M., Basson, G. & Oakley, R.2012, 'ISO/IEC 15504 measurement applied to COBIT process maturity', Benchmarking: An International Journal, vol. 19, no. 2, pp. 159-176.
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The assessment of COBIT process maturity levels for each COBIT process is fraught with many problems regarding the objectivity of the end result. This paper attempts to align the generic aspects of the COBIT 4.1 process maturity scale with the concepts of the Process Attributes of the ISO/IEC 15504-2 measurement scale. The goal behind this alignment attempt is to be able to automatically convert ISO/IEC 15504 assessment profile data captured for processes into their equivalent COBIT process maturity rating, to identify where there is no equivalent process assessment data and to propose how these gaps might be overcome. The end result of this computation of COBIT process maturity levels is to be able to assert that the assessed level is traceable to objective underlying assessment profile data gathered and rated according to the normative requirements of ISO/IEC 15504-2.

Hsieh, T. & Yeh, W.2012, 'Knowledge Discovery Employing Grid Scheme Least Squares Support Vector Machines Based on an Orthogonal Design Bee Colony Algorithm', IEEE Transactions on Systems, Man, and Cybernetics, Part B: Cybernetics, vol. 41, no. 5, pp. 1198-1212.
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This paper proposes a concept for machine learning that integrates a grid scheme (GS) into a least squares support vector machine (LSSVM) (called GS-LSSVM) with a mixed kernel in order to solve data classification problems. The purpose of GS-LSSVM is to execute feature selections, mixed kernel applications, and parameter optimization in a learning paradigm. The proposed learning paradigm includes three steps. First, an orthogonal design is utilized to initialize the number of input features and candidate parameters stored in GS. Then, the features are randomly selected according to the first grid acquired from the first step. These features and the candidate parameters are then passed to LSSVM. Finally, an artificial bee colony algorithm, the recently popular heuristic algorithm, is used to optimize parameters for LSSVM learning. For illustration and evaluation purposes, ten remarkable data sets from the University of California Irvine database are used as testing targets. The experimental results reveal that the proposed GS-LSSVM can produce a classification model more easily interpreted using a small number of features. In terms of accuracy (hit ratio), the GS-LSSVM can significantly outperform other methods listed in this paper. These findings imply that the GS-LSSVM is a promising approach to classification exploration.

Valipour Goudarzi, H. & Foster, S.J.2012, 'Nonlinear analysis of reinforced concrete frames under extreme loadings', Concrete in Australia, vol. 37, no. 3, pp. 48-56.
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Presented in this paper is the formulation and application of a reinforced concrete frame element for nonlinear static, cyclic and dynamic analysis of framed structures under extreme loadings such as earthquake and impact. The effect of material nonlinearity is taken into account and mesh objectivity associated with softening of concrete under compression is addressed. Furthermore, geometrical nonlinearities are considered in the element formulation and effect of membrane action and nonlinearity on the global response of RC frames subjected to extreme loadings is studied. The torsional DOFs are added into element formulation and a simplified model is developed which can take account of interaction between normal and tangential forces (including torque). The formulation accuracy and efficiency are verified by different examples taken from the literature.

Almashaqbeh, O. & McLaughlan, R.G.2012, 'Occurrence of rate limited sorption in stormwater biofiltration systems', International Journal of Environment and Waste Management, vol. 9, no. 3/4, pp. 257-269.
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Batch and column studies were conducted using synthetic stormwater with mixtures of 0.6 mm glass beads and compost particles of either 1.18 or 4.75 mm. Batch tests showed that rate limited uptake of zinc occurred onto both particle sizes. The column containing the 1.18 mm particles could be fitted by a Freundlich sorption isotherm while the other column exhibited a diffuse front and tailing and could not be modelled using equilibrium isotherms. The sorption capacity of the compost for zinc was estimated at 12.5 mg/g and 9.1 mg/g for the 1.18 mm and 4.75 mm particle size fractions, respectively.

Zhang, L., Zhang, L., Tao, D. & huang, x.2012, 'On Combining Multiple Features for Hyperspectral Remote Sensing Image Classification', IEEE Transactions on Geoscience and Remote Sensing, vol. 50, no. 3, pp. 879-893.
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In hyperspectral remote sensing image classification, multiple features, e.g., spectral, texture, and shape features, are employed to represent pixels from different perspectives. It has been widely acknowledged that properly combining multiple features always results in good classification performance. In this paper, we introduce the patch alignment framework to linearly combine multiple features in the optimal way and obtain a unified low-dimensional representation of these multiple features for subsequent classification. Each feature has its particular contribution to the unified representation determined by simultaneously optimizing the weights in the objective function. This scheme considers the specific statistical properties of each feature to achieve a physically meaningful unified low-dimensional representation of multiple features. Experiments on the classification of the hyperspectral digital imagery collection experiment and reflective optics system imaging spectrometer hyperspectral data sets suggest that this scheme is effective.

Keshavarzi, A., Karami Moghadam, M. & Ball, J.E.2012, 'Optimising round-edged entrance of 55 river water intake', Institution of Civil Engineers. Proceedings. Water Management, vol. 165, no. 1, pp. 9-19.
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An experimental study was undertaken to optimise a 55A? round-edged entrance irrigation water intake. The tests were carried out under different flow conditions in a laboratory flume with a rectangular cross-section under close-ended and open-ended flow conditions. To improve the efficiency of water intake, its entrance was rounded with three different radii (r): 100, 150 and 200 mm. Two components of flow velocity in transverse and flow directions were measured using an electromagnetic velocity meter. The flow velocity inside the water intake was measured at 390 regular grid points, across three horizontal layers at 30, 60 and 120 mm heights from the bed. The streamlines were drawn from the captured flow velocity, and hence the separation width and length were determined for the different depth levels, from the bed to the water surface. The discharge ratios (Q r) of the main channel to the lateral channel were set equal to 0A?25, 0A?67, 1A?5 and 4. It was found that a 55A? water intake with the radius of curvature of r/W b = 0A?8 produced minimum separation size. It was therefore selected as the optimum 55A? round-edged entrance water intake.

Zhang, Y., Sun, G., Li, G., Luo, Z. & Li, Q.2012, 'Optimization of foam-filled bitubal structures for crashworthiness criteria', Materials & Design, vol. 38, pp. 99-109.
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Thin-walled structures have been widely used as key components in automobile and aerospace industry to improve the crashworthiness and safety of vehicles while maintaining overall light-weight. This paper aims to explore the design issue of thin-walled bitubal column structures filled with aluminum foam. As a relatively new filler material, aluminum foam can increase crashworthiness without sacrificing too much weight. To optimize crashworthiness of the foam-filled bitubal square column, the Kriging meta-modeling technique is adopted herein to formulate the objective and constraint functions. The genetic algorithm (GA) and Non-dominated Sorting Genetic Algorithm II (NSGA II) are used to seek the optimal solutions to the single and multiobjective optimization problems, respectively. To compare with other thin-walled configurations, the design optimization is also conducted for empty bitubal column and foam-filled monotubal column. The results demonstrate that the foam-filled bitubal configuration has more room to enhance the crashworthiness and can be an efficient energy absorber.

Hossain, S. & McLaughlan, R.G.2012, 'Oxidation of Chlorophenols in Aqueous Solution by Excess Potassium Permanganate', Water, Air, & Soil Pollution, vol. 223, no. 3, pp. 1429-1435.
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A simple spectrophotometric method was developed to quantify chlorophenol (CP) concentrations after reaction with potassium permanganate and quenching with sodium sulfite. Other quenching agents (peroxide, sodium thiosulfate and hydroxylamine hydrochloride) were found to create absorbance in the spectral range required for CP quantification. Analysis at pH 12 gave greater absorption and sensitivity for the method compared with pH 5.6. The calibration curves of the proposed methods were linear in the concentration ranges 0.0061a??0.61 and 0.0078a??0.78 mM with detection limit of 0.0006 and 0.0008 mM for dichlorophenols and monochlorophenols, respectively. The oxidation kinetics of five chlorophenols in aqueous solution with excess potassium permanganate were evaluated using the analytical method. The pseudo-first-order reaction rates were found to be relatively rapid 1.42?? 10a??3 to 0.024 sa??1 and followed the sequence 2-chlorophenol (2-CP)>2,6-dichlorophenol (2,6-DCP)>4-chlorophenol (4-CP)>2,4-dichlorophenol (2, 4-DCP)>3-chlorophenol (3-CP). The apparent second-order rate constant was calculated from the measured pseudo-first-order rate constant with respect to CP with initial KMnO4 concentration (1.5 mM) and follows the same sequence of pseudo-first-order rate constant. This shows that chlorine atoms in the structure of chlorophenol had a significant influence on the oxidation of chlorophenols by potassium permanganate. Permanganate can be used for the treatment of chlorophenol-contaminated soil and groundwater.

huang, q., Tao, D., li, x. & Liew, A.2012, 'Parallelized Evolutionary Learning for detection of Biclusters in Gene Expression Data', IEEE/ACM Transactions on Computational Biology and Bioinformatics, vol. 9, no. 2, pp. 560-570.

Engels, B., Jannot, G., Remenyi, J., Simard, M.J. & Hutvagner, G.2012, 'Polypyrimidine tract binding protein (hnRNP I) is possibly a conserved modulator of miRNA-mediated gene regulation.', PLoS One, vol. 7, no. 3.
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MiRNAs can regulate gene expression through versatile mechanisms that result in increased or decreased expression of the targeted mRNA and it could effect the expression of thousands of protein in a particular cell. An increasing body of evidence suggest that miRNAs action can be modulated by proteins that bind to the same 39UTRs that are targeted by miRNAs, suggesting that other factors apart from miRNAs and their target sites determine miRNA-modulation of gene expression. We applied an affinity purification protocol using biotinylated let-7 miRNA inhibitor to isolate proteins that are involved in let-7 mediated gene regulation that resulted in an affinity purification of Polypyrimidine Tract Binding protein (PTB). Here we show that PTB interacts with miRNAs and human Argonaute 2 (hAgo2) through RNA as well as identified potential mammalian cellular targets that are co-regulated by PTB and hAgo2. In addition, using genetic approach, we have demonstrated that PTB genetically interacts with Caenorhabditis elegans let-7 indicating a conserved role for PTB in miRNAmediated gene regulation.

Keshavarzi, A., Gazni, R. & Homayoon, R.2012, 'Prediction of scouring around an arch-shaped bed sill using Neuro-Fuzzy model', Applied Soft Computing, vol. 12, no. 1, pp. 486-493.
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In this study, Adaptive Neuro-Fuzzy Inference System (ANFIS) has been used to model local scouring depth and pattern scouring around concave and convex arch shaped circular bed sills. The experimental part of this research study includes seven sets of laboratory test cases which were performed in an experimental flume under different flow conditions. A data set consists of 2754 data points of scouring depth were collected to use in the ANFIS model. The ratio of arch diameter, D, to flume width, W, is used as a non dimensional variables in all test cases. The results from ANFIS model were compared with the results of ANN model obtained by Homayoon et al. [24] and previously presented models. The results indicated that for D/W equal to 1 and 1.2, the ANFIS models produced a good performance for convex and concave bed sills. As a result, the ANFIS models can be used as an alternative to ANN for estimation of scour depth and scour pattern around a concave bed sill installed with a bridge pier.

Song, M., Tao, D., Chen, C., Bu, j., Luo, J. & Zhang, C.2012, 'Probabilistic Exposure Fusion', IEEE Transactions On Image Processing, vol. 21, no. 1, pp. 341-357.
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The luminance of a natural scene is often of high dynamic range (HDR). In this paper, we propose a new scheme to handle HDR scenes by integrating locally adaptive scene detail capture and suppressing gradient reversals introduced by the local adaptation. The proposed scheme is novel for capturing an HDR scene by using a standard dynamic range (SDR) device and synthesizing an image suitable for SDR displays. In particular, we use an SDR capture device to record scene details (i.e., the visible contrasts and the scene gradients) in a series of SDR images with different exposure levels. Each SDR image responds to a fraction of the HDR and partially records scene details. With the captured SDR image series, we first calculate the image luminance levels, which maximize the visible contrasts, and then the scene gradients embedded in these images. Next, we synthesize an SDR image by using a probabilistic model that preserves the calculated image luminance levels and suppresses reversals in the image luminance gradients. The synthesized SDR image contains much more scene details than any of the captured SDR image. Moreover, the proposed scheme also functions as the tone mapping of an HDR image to the SDR image, and it is superior to both global and local tone mapping operators. This is because global operators fail to preserve visual details when the contrast ratio of a scene is large, whereas local operators often produce halos in the synthesized SDR image. The proposed scheme does not require any human interaction or parameter tuning for different scenes. Subjective evaluations have shown that it is preferred over a number of existing approaches.

Craig, A.R., Tran, Y.H., Wijesuriya, N. & Nguyen, H.T.2012, 'Regional brain wave activity changes associated with fatigue', Psychophysiology, vol. 49, pp. 574-582.
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Assessing brain wave activity is a viable strategy for monitoring fatigue when performing tasks such as driving, and numerous studies have been conducted in this area. However, results of a systematic review on changes in brain wave activity associated with fatigue have revealed equivocal findings. This study investigated brain wave activity associated with fatigue in 48 nonprofessional healthy drivers as they participated in a simulated driving task until they fatigued. The results showed that as a person fatigues, slow wave activity increased over the entire cortex, in theta and in alpha 1 and 2 bands, while no significant changes were found in delta wave activity. Substantial increases also occurred in fast wave activity, though mostly in frontal sites. The results suggest that as a person fatigues, the brain loses capacity and slows its activity, and that attempts to maintain vigilance levels lead to increased beta activity.

Mohammed, T.M., Aryal, R., Vigneswaran, S., Loganathan, P., Kandasamy, J.K. & Naidu, R.2012, 'Removal of heavy metals in stormwater by hydrous ferric oxide', Institution of Civil Engineers. Proceedings. Water Management, vol. 165, no. WM3, pp. 171-178.
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Stormwater runoff from urban and industrial areas contains several types of heavy metals that have negative ecological impacts on receiving waters, and therefore methods need to be developed to remove these pollutants. Combined removal of a mixture of heavy metal cations (Cu2??, Zn2??, Cd2??, and Ni2??) and an oxy anion (selenate, SeO42) from an artificially prepared stormwater was investigated by sorption of these heavy metals on hydrous ferric oxide (HFO) in a column experiment under intermittent runoff (wetting and drying) condition, as occurs between rainfall events in the field. The heavy metal removal behaviour varied between ions as well as with time. In each continuous column run (8 h) the amount of ions removed progressively decreased with time and reached a constant level at approximately 4a??6 h. However, stopping the runoff for 40 h and starting the next runoff after this period removed a large quantity of heavy metals in the first few hours of this run. The intermittent runoff for seven runs showed that HFO has a high capacity to remove copper and zinc, which were present in higher concentrations in the stormwater than cadmium, nickel and selenium.

Rana, M. & Sanagavarapu, A.M.2012, 'Segmented-Locally-One-Dimensional-FDTD Method for EM Propagation Inside Large Complex Tunnel Environments', IEEE Transactions On Magnetics, vol. 48, no. 2, pp. 223-226.
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We propose a novel segmented locally one dimensional finite difference time domain (S-LOD-FDTD) method for modeling the electromagnetic wave propagation inside electrically large tunnels. The proposed S-LOD-FDTD method reduces the computational resources by dividing the problem space into segments. To validate this method, we simulate the propagation in real tunnels and compare the results with the published measured data. The comparisons reveal that the proposed method can predict the fields accurately in real, large tunnels at longer ranges with significant savings in execution time and memory.

Rana, M. & Sanagavarapu, A.M.2012, 'Segmented-Locally-One-Dimensional-FDTD Method for EM Propagation Inside Large Complex Tunnel Environments', IEEE Transactions On Magnetics, vol. 48, no. 2, pp. 223-226.
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We propose a novel segmented locally one dimensional finite difference time domain (S-LOD-FDTD) method for modeling the electromagnetic wave propagation inside electrically large tunnels. The proposed S-LOD-FDTD method reduces the computational resources by dividing the problem space into segments. To validate this method, we simulate the propagation in real tunnels and compare the results with the published measured data. The comparisons reveal that the proposed method can predict the fields accurately in real, large tunnels at longer ranges with significant savings in execution time and memory.

Cheng, S., Ting, S.R., Lucien, F. & Zetterlund, P.B.2012, 'Size-tunable nanoparticle synthesis by RAFT polymerization in CO2-induced miniemulsions', Macromolecules, vol. 45, pp. 1803-1810.
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A novel environmentally friendly low-energy emulsification method that relies on pressurization with CO2 to low pressure has been applied to reversible addition-fragmentation chain transfer (RAFT) polymerization of styrene-in-water miniemulsions with the anionic surfactant Dowfax 8390. This method circumvents traditional high-energy homogenization, and over a certain CO2 pressure range, a transparent miniemulsion is formed. RAFT polymerization of styrene using benzyldodecyl trithiocarbonate and the aqueous phase initiator VA-044 was carried out successfully in CO2-induced miniemulsions at 50 A?C with good control/livingness. Interestingly, the particle size could be conveniently tuned via the CO2 pressure without altering the recipe, with 6.00, 6.50, and 7.50 MPa generating numberaverage particle diameters of 98, 89, and 48 nm, respectively, at 70% conversion. The smallest particle size corresponded to the pressure range within which the emulsion was transparent.

Luo, Z., Zhang, N., Gao, W. & Ma, H.2012, 'Structural shape and topology optimization using a meshless Galerkin level set method', International Journal For Numerical Methods In Engineering, vol. 90, no. 3, pp. 369-389.
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This paper aims to propose a meshless Galerkin level set method for shape and topology optimization of continuum structures. To take advantage of the implicit free boundary representation scheme, the design boundary is represented as the zero level set of a scalar level set function, to flexibly handle complex shape fidelity and topology changes by maintaining concise and smooth interface. Compactly supported radial basis functions (CSRBFs) are used to parameterize the level set function and construct the shape functions for meshfree approximations based on a set of unstructured field nodes. The meshless Galerkin method with global weak form is used to implement the discretization of the state equations. This provides a pathway to unify the two different numerical stages in most conventional level set methods: (1) the propagation of discrete level set function on a set of Eulerian grid and (2) the approximation of discrete equations on a set of Lagrangian mesh. The original more difficult shape and topology optimization based on the level set equation is transformed into a relatively easier size optimization, to which many efficient optimization algorithms can be applied. The proposed level set method can describe the moving boundaries without remeshing for discontinuities. The motion of the free boundary is just a question of advancing the discrete level set function in time by solving the size optimization. Several benchmark examples are used to demonstrate the effectiveness of the proposed method. The numerical results show that the proposed method can simplify numerical process and avoid numerical difficulties involved in most conventional level set methods. It is straightforward to apply the proposed method to more advanced shape and topology optimization problems. Copyright A? 2011 John Wiley & Sons, Ltd.

Kang, Z., Wang, X. & Luo, Z.2012, 'Topology optimization for static shape control of piezoelectric plates with penalization on intermediate actuation voltage', Journal Of Mechanical Design, vol. 134, pp. 051006-1-051006-9.
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This paper investigates the simultaneous optimal distribution of structural material and trilevel actuation voltage for static shape control applications. In this optimal design problem, the shape error between the actuated and the desired shapes is chosen as the objective function. The energy and the material volume are taken as constraints in the optimization problem formulation. The discrete-valued optimization problem is relaxed using element-wise continuous design variables representing the relative material density and the actuation voltage level. Artificial interpolation models which relate the mechanical piezoelectrical properties of the material and the actuation voltage to the design variables are employed. Therein, power-law penalization functions are used to suppress intermediate values of both the material densities and the control voltage. The sensitivity analysis procedure is discussed, and the design variables are optimized by using the method of moving asymptotes (MMA). Finally, numerical examples are presented to demonstrate the applicability and effectiveness of the proposed method. It is shown that the proposed method is able to yield distinct material distribution and to suppress intermediate actuation voltage values as required.

Henderson-Sellers, B., Qureshi, M. & Gonzalez-Perez, C.2012, 'Towards an interoperable metamodel suite: size assessment as one input', International Journal of Software and Informatics, vol. 6, no. 2.
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In recent years, many metamodels have been introduced in the software engi- neering literature and standards. These metamodels vary in their focus across, for example, process, product, organizational and measurement aspects of software development and have typically been developed independently of each other with shared concepts being only ac- cidental. There is thus an increasing concern in the standards communities that possible conA?icts of structure and semantics between these various metamodels will hinder their widespread adoption. The complexity of these metamodels has also increased signiA?cantly and is another barrier in their appreciation. This complexity is compounded when more than one metamodel is used in the lifecycle of a software project. Therefore there is a need to have interoperable metamodels. As a A?rst step towards engendering interoperability and/or possible mergers between metamodels, we examine the size and complexity of various meta- models. To do this, we have used the Rossi and Brinkkemper metrics-based approach to evaluate the size and complexity of several standard metamodels including UML 2.3, BPMN 2.0, ODM, SMM and OSM. The size and complexity of these metamodels is also compared with the previous version of UML, BPMN and Activity diagrams. The comparatively large sizes of BPMN 2.0 and UML 2.3 suggest that future integration with these metamodels might be more diA?cult than with the other metamodels under study (especially ODM, SSM and OSM).

Ji, J., Li, X., Luo, Z. & Zhang, N.2012, 'Two-to-one resonant hopf bifurcations in a quadratically nonlinear oscillator involving time delay', International Journal of Bifurcation and Chaos, vol. 22, no. 3, pp. 1250060-1-1250060-14.
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The trivial equilibrium of a weakly nonlinear oscillator having quadratic nonlinearities under a delayed feedback control can change its stability via a single Hopf bifurcation as the time delay increases. Double Hopf bifurcation occurs when the characteristic equation has two pairs of purely imaginary solutions. An interaction of resonant Hopf-Hopf bifurcations may be possible when the two critical time delays corresponding to the two Hopf bifurcations have the same value. With the aid of normal form theory and centre manifold theorem as well as the method of multiple scales, the present paper studies the dynamics of a quadratically nonlinear oscillator involving time delay in the vicinity of the point of two-to-one resonances of Hopf-Hopf bifurcations. The ratio of the frequencies of two Hopf bifurcations is numerically found to be nearly equal to two. The two resonant Hopf bifurcations can generate two respective periodic solutions. Consequently, the centre manifold corresponding to these two solutions is determined by a set of four first-order differential equations under two-to-one internal resonances. It is shown that the amplitudes of the two bifurcating periodic solutions admit the trivial solution and two-mode solutions for the averaged equations on the centre manifolds. Correspondingly, the cumulative behavior of the original nonlinear oscillator exhibits the initial equilibrium and a quasi-periodic motion having two frequencies. Illustrative examples are given to show the unstable zero solution, stable zero solution, and stable two-mode solution of the nonlinear oscillator under the two-to-one resonant Hopf-Hopf interactions.

Yuwono, M., Moulton, B.D., Su, S.W., Celler, B.G. & Nguyen, H.T.2012, 'Unsupervised machine-learning method for improving the performance of ambulatory fall-detection systems', Biomedical Engineering Online, vol. 11, no. 9, pp. 1-11.
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Background: Falls can cause trauma, disability and death among older people. Ambulatory accelerometer devices are currently capable of detecting falls in a controlled environment. However, research suggests that most current approaches can tend to have insufficient sensitivity and specificity in non-laboratory environments, in part because impacts can be experienced as part of ordinary daily living activities. Method: We used a waist-worn wireless tri-axial accelerometer combined with digital signal processing, clustering and neural network classifiers. The method includes the application of Discrete Wavelet Transform, Regrouping Particle Swarm Optimization, Gaussian Distribution of Clustered Knowledge and an ensemble of classifiers including a multilayer perceptron and Augmented Radial Basis Function (ARBF) neural networks. Results: Preliminary testing with 8 healthy individuals in a home environment yields 98.6% sensitivity to falls and 99.6% specificity for routine Activities of Daily Living (ADL) data. Single ARB and MLP classifiers were compared with a combined classifier. The combined classifier offers the greatest sensitivity, with a slight reduction in specificity for routine ADL and an increased specificity for exercise activities. In preliminary tests, the approach achieves 100% sensitivity on in-group falls, 97.65% on out-group falls, 99.33% specificity on routine ADL, and 96.59% specificity on exercise ADL. Conclusion: The pre-processing and feature-extraction steps appear to simplify the signal while successfully extracting the essential features that are required to characterize a fall. The results suggest this combination of classifiers can perform better than MLP alone. Preliminary testing suggests these methods may be useful for researchers who are attempting to improve the performance of ambulatory falldetection systems.

Abdul Rahman, S., Walker, P.D., Zhang, N., Zhu, J. & Du, H. 2012, 'A Comparative study of vehicle drive performance and energy efficiency', International Conference on Sustainable Automotive Technologies, Melbourne, Victorial, Australia, March 2012 in Proceedings of the 4th International Conference on Sustainable Automotive Technologies, ed Subic, A.; Wellnitz, J.; Leary, M.; Koopmans, L., Springer, Heidelberg, Germany, pp. 319-324.
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In this paper, two typres of increasingly more efficient and greener vehicles are analyzed and compared. These vehicles are: a proposed conceptual series-parrallel powertrain, the University of Technology, Sydney plug-in hybrid electric vehicle (UTS PHEV); and, a conventional series-parrallel hybrid electric vehicle with an internal combustion engine. The UTS PHEV requires only a single electric machine to function as an electric motor or generator in different time intervals controlled by a special energy management strategy. The UTS PHEV uses two energy storage device, the battery and the untracapacitor, which can work together effectively to maintain the state of charge at a high level in order to improve the vehicle drive performance and energy efficiency. With the assistance of a novel automatic transmission, the UTS PHEV can operate under multiple modes to suit the needs of various driving cycles including those in an emergency. A special power and energy management strategy was developed to control the power flows within the vehicle according to the desired operating mode.

Tabatabaiefar, S., Fatahi, B. & Samali, B. 2012, 'Effects of soil dynamic properties and bedrock depth on seismic response of building frames incorporation soil-structure interaction', the 5th Asia-Pacific Conference on Unsaturated Soils Theory and Practice, Thailand, November 2011 in Proceedings of the 5th Asia-Pacific Conference on Unsaturated Soils Theory and Practice, ed Jotisankasa, A; Sawangsuriya, A; Soralump, S; Mairaing, W, Kasetsart University, Thailand, pp. 597-603.
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In this study, a ten storey moment resisting building frame, resting on a shallow foundation,is selected in conjunction with three soil types with the shear wave velocities less than 600m/s, representing classes Ce, De and Ee, according to AS 1170.4. Different bedrock depths including 10m, 20m, and 30 m are employed in the numerical modelling using finite difference software FLAC 2D. Fully nonlinear dynamic analysis under influence of different earthquake records is conducted, and the results of the three different cases are compared and discussed. The results indicate that the dynamic properties of the subsoil such as shear wave velocity as well as bedrock depth play significant roles in seismic response of the building frames under the influence of soil-structure interaction. As the shear wave velocity of the subsoil decreases and bedrock depth increases, lateral deflections and inter-storey drifts of the structures increase. The mentioned effects can change the performance level of the structures from life safe to near collapse or total collapse. Therefore, the conventional design procedure excluding SSI is no longer adequate to guarantee the structural safety for the building frames resting on soft soil deposits.

Walker, P.D., Abdul Rahman, S., Zhang, N., Zhan, W., Lin, Y. & zhu, b. 2012, 'Modelling and simulation of a two speed electric vehicle', International Conference on Sustainable Automotive Technologies, Melbourne, Victorial, Australia, March 2012 in Proceedings of the 4th International Conference on Sustainable Automotive Technologies, ed Subic, A.; Wellnitz, J.; Leary, M.; Koopmans, L., Springer, Heidelberg, Germany, pp. 193-198.
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Electric vehicles offer an alternative to hybrid and conventional vehicles through the use of electcric drive without fossil fuel consumption. This shifts green house gas production from the vehicle to power stations, but if power is supplied from renewable sources, such as wind power, zero emissions are generated. Practical vehicle design requires the consieration of competing demands of vehicle acceleration and performance against range and vehicle efficiency. Thus, considering requirements such as grade climbing and acceleration against vehicle range and power consumption, a two speed transmission is suggested for this vehicle study to increase motor operation at high torque and efficiency regions. To evaluate the application of such a transmission, a two speed electric vehicle powertrain is developed in SimulinkA?. Simulations are conducted to demonstrate the performance of the two speed electric vehicle. Results reveal the capability of the two speed vehicle to meet various performance criteria and provide an indication of effective range under different drive cycles.

Braun, R.M. & Chaczko, Z. 2012, 'Multi-dimensional Information Space View of Wireless Sensor Networks with Optimization applications', Computer Aided Systems Theory - EUROCAST 2011, Las Palmas de Gran Canaria, Spain, February 2011 in LNCS - Computer Aided Systems Theory -- EUROCAST 2011, ed Moreno D?-az, Roberto; Pichler, Franz; Quesada Arencibia, Alexis, Springer, Germany, pp. 146-152.
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This paper presents an optimization example using a new paradigm for viewing the work of Wireless Sensor Networks. In our earlier paper [1] the Observed Field (OF) is described as a multi-dimensional Information Space (ISp). The Wireless Sensor Network is described as a Transformation Space (TS), while the information collector is a single point consumer of information, described as an Information Sink (ISi). Formal mathematical descriptions were suggested for the OF and the ISp. We showed how the TS can be formally thought of as a multi-dimensional transform function between ISp and ISi. It can be aggregated into a notional multi-dimensional value between {0, 1}. In this paper, this formal mathematical description is used to create a genetic algorithm based optimization strategy for creating routes through the TS, using a cost function based on mutual information. The example uses a connectivity array, a mutual information array and the PBIL algorithm.

Rujikiatkamjorn, C., Indraratna, B. & Fatahi, B. 2012, 'Numerical prediction of unsaturated ground behavior influenced by vegetation and vacuum consolidation', The 5th Asia-Pacific Conference on Unsaturated Soils Theory and Practice, Thailand, November 2011 in Proceedings of the 5th Asia-Pacific Conference on Unsaturated Soils Theory and Practice, ed Jotisankasa, A; Sawangsuriya, A; Soralump, S; Mairaing, W, Kasetsart University, Thailand, pp. 851-856.
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Bioengineering including native vegetation is an ancient method of improving the stability of slopes. In modern railway engineering, this technique is re-captured for increasing the soil stiffness and shear strength of subgrade beneath rail tracks. Currently this practice has become increasingly popular in Australia for stabilising railway corridors built over expansive clays and compressive soft soils. This paper looks at the stabilisation role by suction generated by both the natural vegetation and the artificial vacuum application using the numerical analysis. For demonstrating the role of native vegetation, a mathematical model for the rate of root water uptake was incorporated in the analysis. The soil moisture content distribution and the soil matric suction profile adjacent to the tree were numerically captured based on the general effective stress theory of unsaturated soil. For vacuum application, the equivalent plane strain theory was employed to simulate radial consolidation and artificially applied suction. The performance of both techniques on track constructed on soft formation was discussed and compared in terms of settlement and associated pore pressure.

Xu, M., He, X.S., Hasan, M.A. & Chen, L. 2012, 'Shot Classification Using Domain Specific Features for Movie Management', Busan, South Korea, April 2012 in Database Systems for Advanced Applications, ed Sang-goo Lee et al., Springer Heidelberg Dordrecht London NewYork, Busan, South Korea, pp. 314-318.
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Among many video types, movie content indexing and retrieval is a significantly challenging task because of the wide variety of shooting techniques and the broad range of genres. A movie consists of a series of video shots. Managing a movie at shot level provides a feasible way for movie understanding and summarization. Consequently, an effective shot classification is greatly desired for advanced movie management. In this demo, we explore novel domain specific features for effective shot classification. Experimental results show that the proposed method classifies movie shots from wide range of movie genres with improved accuracy compared to existing work.

Lozano, A., Peters, G., Liu, D., Waldron, K. 2012, 'Study of Ant Locomotion in Surface Transitions for Climbing Robot Design', Paris, France, August 2011 in 14th International Conference on Climbing and Walking Robots and the Support Technologies for Mobile Machines (CLAWAR2011), ed Bidaud, Philippe et al., World Scientific, Hackensack, N.J., pp. 173-180.