Publications

Tong, L & Luo, Q 2008, 'Analysis of Cracked Lap Shear (CLS) Joints' in Modeling of Adhesively Bonded Joints, Springer Berlin Heidelberg, pp. 25-51.
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This chapter presents analytical models for cracked lap shear joints. Two analytical frameworks are introduced: (1) the overlap is treated as an entire beam to find displacements and force components of the cracked lap shear joints firstly, and then the adherends in the overlap region are treated as individual beams to find adhesive stresses and energy release rates; (2) individual beams are considered only; displacements, force components and adhesive stresses are determined simultaneously by solving the coupled differential equations. Geometrically-nonlinear features of cracked lap shear joints are investigated. Strength of materials and fracture mechanics based failure criteria are discussed. © 2008 Springer Berlin Heidelberg.

Wang, Z, Huang, S & Dissanayake, G 2008, 'Tradeoffs in SLAM with sparse information filters' in Laugier, C & Siegwart, R (eds), Field and Service Robotics, Springer, Berlin Heidelberg, pp. 339-348.
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Designing filters exploiting the sparseness of the information matrix for efficiently solving the simultaneous localization and mapping (SLAM) problem has attracted significant attention during the recent past. The main contribution of this paper is a review of the various sparse information filters proposed in the literature to date, in particular, the compromises used to achieve sparseness. Two of the most recent algorithms that the authors have implemented, Exactly Sparse Extended Information Filter (ESEIF) by Walter et al. [5] and the D-SLAM by Wang et al. [6] are discussed and analyzed in detail. It is proposed that this analysis can stimulate developing a framework suitable for evaluating the relative merits of SLAM algorithms. © 2008 Springer-Verlag Berlin Heidelberg.

Bennett, NS, Cowern, NEB, Smith, AJ, Kah, M, Gwilliam, RM, Sealy, BJ, Noakes, TCQ, Bailey, P, Giubertoni, D & Bersani, M 2008, 'Differential Hall characterisation of ultrashallow doping in advanced Si-based materials', Materials Science and Engineering: B, vol. 154-155, pp. 229-233.
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Bennett, NS, Radamson, HH, Beer, CS, Smith, AJ, Gwilliam, RM, Cowern, NEB & Sealy, BJ 2008, 'Enhanced n-type dopant solubility in tensile-strained Si', Thin Solid Films, vol. 517, no. 1, pp. 331-333.
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Bennett, NS, Smith, AJ, Gwilliam, RM, Webb, RP, Sealy, BJ, Cowern, NEB, O’Reilly, L & McNally, PJ 2008, 'Antimony for n-type metal oxide semiconductor ultrashallow junctions in strained Si: A superior dopant to arsenic?', Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures Processing, Measurement, and Phenomena, vol. 26, no. 1, pp. 391-395.
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The creation of stable, highly conductive ultrashallow junctions in strained Si is a key requirement for future Si based devices. It is shown that in the presence of tensile strain, Sb becomes a strong contender to replace As as the dopant of choice due to advantages in junction depth, junction steepness, and crucially, sheet resistance. While 0.7% strain reduces resistance for both As and Sb, a result of enhanced electron mobility, the reduction is significantly larger for Sb due to an increase in donor activation. Differential Hall and secondary-ion mass spectroscopy measurements suggest this to be a consequence of a strain-induced Sb solubility enhancement following epitaxial regrowth, increasing Sb solubility in Si to levels approaching 1021cm−3. Advantages in junction depth, junction steepness, and dopant activation make Sb an interesting alternative to As for ultrashallow doping in strain-engineered complementary metal-oxide semiconductor devices.

Clarysse, T, Bogdanowicz, J, Goossens, J, Moussa, A, Rosseel, E, Vandervorst, W, Petersen, DH, Lin, R, Nielsen, PF, Hansen, O, Merklin, G, Bennett, NS & Cowern, NEB 2008, 'On the analysis of the activation mechanisms of sub-melt laser anneals', Materials Science and Engineering: B, vol. 154-155, pp. 24-30.
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Cowern, NEB, Smith, AJ, Bennett, NS, Sealy, BJ, Gwilliam, R, Webb, RP, Colombeau, B, Paul, S, Lerch, W & Pakfar, A 2008, 'Vacancy Engineering – An Ultra-Low Thermal Budget Method for High-Concentration 'Diffusionless' Implantation Doping', Materials Science Forum, vol. 573-574, pp. 295-304.
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This paper reviews the physics and the potential application of ion-implanted vacanciesfor high-performance B-doped ultra-shallow junctions. By treatment of silicon films with vacancygeneratingimplants prior to boron implantation, electrically active boron concentrationsapproaching 1021 cm-3 can be achieved by Rapid Thermal Annealing at low temperatures, withoutthe use of preamorphisation. Source/drain (S/D) junctions formed by advanced vacancy engineeringimplants (VEI) are activated far above solubility. Furthermore, in the case of appropriatelyengineered thin silicon films, this activation is stable with respect to deactivation and the dopingprofile is practically diffusionless. Sheet resistance Rs is predicted to stay almost constant withdecreasing junction depth Xj, thus potentially outperforming other S/D engineering approaches atthe ‘32 nm node’ and beyond.

Deuse, J, Krebs, M, Droste, M & Döhrer, K 2008, 'Bauteilreinigung im Wertstrom', Zeitschrift für wirtschaftlichen Fabrikbetrieb, vol. 103, no. 9, pp. 598-601.
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Kurzfassung In einer prozessorientierten Produktion stellt das kontinuierliche Fließen der Produkte durch die wertschöpfenden Prozesse heutzutage einen wesentlichen Ansatz zur wirtschaftlichen Fertigung dar. Gleichzeitig nimmt die Bedeutung der oft zentral organisierten und auf Batchbetrieb ausgelegten Bauteilreinigung auf Grund von gestiegenen Reinheitsanforderungen in der industriellen Praxis stark zu. Durch das innovative Verfahren der Vibrationsreinigung mit seiner Inlinefähigkeit und Ein-Stück-Reinigung wird versucht, diese konträren Entwicklungen zu kompensieren. Dieser Beitrag stellt daher am Beispiel der Vibrationsreinigungstechnik dar, wie Bauteilreinigungsanlagen mit Hilfe von Handhabungseinrichtungen in den Wertstrom integriert werden können.

Du, Y, Chen, L & Luo, Z 2008, 'Topology synthesis of geometrically nonlinear compliant mechanisms using meshless methods', Acta Mechanica Solida Sinica, vol. 21, no. 1, pp. 51-61.
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This paper presents a new method for topology optimization of geometrical nonlinear compliant mechanisms using the element-free Galerkin method (EFGM). The EFGM is employed as an alternative scheme to numerically solve the state equations by fully taking

Gao, W, Zhang, N, Ji, JC & Du, HP 2008, 'Dynamic analysis of vehicles with uncertainty', PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART D-JOURNAL OF AUTOMOBILE ENGINEERING, vol. 222, no. D5, pp. 657-664.
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The probabilistic and interval dynamic analysis of cars with uncertain parameters under random road input excitations by using a two-degree-of-freedom car model are presented in this paper. In the probabilistic analytical model, the vehicle parameters, including the sprung mass, unsprung mass, suspension damping, suspension, and tyre stiffness, are considered as random variables. The mean value, standard deviation, and variation coefficient of the vehicle's natural frequencies and mode shapes are obtained by using the Monte Carlo simulation method. Then, the computational expressions for the numerical characteristics of the mean square value of the vehicle's random response in the frequency domain are developed by means of the random variable's functional moment method. Considering the vehicle parameters as interval variables, the lower bound, upper bound, and interval change ratio value of the vehicle's random responses are obtained by means of the interval operations. The influences of the uncertainty of the vehicle parameters on the vehicle's natural frequencies, mode shapes, and dynamic responses are investigated in detail using a practical example. The comparison of the vehicle's dynamic characteristics using the probabilistic and interval analysis are also demonstrated. © IMechE 2008.

Horan, K, Lankinen, A, O’Reilly, L, Bennett, NS, McNally, PJ, Sealy, BJ, Cowern, NEB & Tuomi, TO 2008, 'Structural and electrical characterisation of ion-implanted strained silicon', Materials Science and Engineering: B, vol. 154-155, pp. 118-121.
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Huang, S, Wang, Z & Dissanayake, G 2008, 'Sparse Local Submap Joining Filter for Building Large-Scale Maps', IEEE TRANSACTIONS ON ROBOTICS, vol. 24, no. 5, pp. 1121-1130.
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This paper presents a novel local submap joining algorithm for building large-scale feature-based maps: sparse local submap joining filter (SLSJF). The input to the filter is a sequence of local submaps. Each local submap is represented in a coordinate frame defined by the robot pose at which the map is initiated. The local submap state vector consists of the positions of all the local features and the final robot pose within the submap. The output of the filter is a global map containing the global positions of all the features as well as all the robot start/end poses of the local submaps. Use of an extended information filter (EIF) for fusing submaps makes the information matrix associated with SLSJF exactly sparse. The sparse structure together with a novel state vector and covariance submatrix recovery technique makes the SLSJF computationally very efficient. The SLSJF is a canonical and efficient submap joining solution for large-scale simultaneous localization and mapping (SLAM) problems that makes use of consistent local submaps generated by any reliable SLAM algorithm. The effectiveness and efficiency of the new algorithm is verified through computer simulations and experiments. © 2008 IEEE.

Ji, JC & Zhang, N 2008, 'Additive resonances of a controlled van der Pol-Duffing oscillator', JOURNAL OF SOUND AND VIBRATION, vol. 315, no. 1-2, pp. 22-33.
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The trivial equilibrium of a controlled van der Pol-Duffing oscillator with nonlinear feedback control may lose its stability via a non-resonant interaction of two Hopf bifurcations when two critical time delays corresponding to two Hopf bifurcations have the same value. Such an interaction results in a non-resonant bifurcation of co-dimension two. In the vicinity of the non-resonant Hopf bifurcations, the presence of a periodic excitation in the controlled oscillator can induce three types of additive resonances in the forced response, when the frequency of the external excitation and the frequencies of the two Hopf bifurcations satisfy a certain relationship. With the aid of centre manifold theorem and the method of multiple scales, three types of additive resonance responses of the controlled system are investigated by studying the possible solutions and their stability of the four-dimensional ordinary differential equations on the centre manifold. The amplitudes of the free-oscillation terms are found to admit three solutions; two non-trivial solutions and the trivial solution. Of two non-trivial solutions, one is stable and the trivial solution is unstable. A stable non-trivial solution corresponds to a quasi-periodic motion of the original system. It is also found that the frequency-response curves for three cases of additive resonances are an isolated closed curve. It is shown that the forced response of the oscillator may exhibit quasi-periodic motions on a three-dimensional torus consisting of three frequencies; the frequencies of two bifurcating solutions and the frequency of the excitation. Illustrative examples are given to show the quasi-periodic motions. © 2008 Elsevier Ltd. All rights reserved.

Ji, JC, Hansen, CH & Zander, AC 2008, 'Nonlinear Dynamics of Magnetic Bearing Systems', JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES, vol. 19, no. 12, pp. 1471-1491.
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Magnetic bearings use magnetic forces to support various machine components. Because of the non-contact nature of this type of suspension, magnetic bearing technology offers a number of significant advantages over conventional bearings, such as rolling element and fluid film bearings. An active magnetic bearing basically consists of an electromagnetic actuator, position sensors, power amplifiers, and a feedback controller. All of these components are characterized by nonlinear behavior and therefore the entire system is inherently nonlinear. However, in simulations of the dynamic behavior of magnetic bearing systems, the nonlinearities are usually neglected to simplify the analysis and only linear models are used. Moreover, many control techniques currently used in magnetic bearing systems are generally designed by ignoring nonlinear effects. The main reason for simplification is the intractability of the complexity of the actual model. In fact, the inherent nonlinear properties of magnetic bearing systems can lead to dynamic behavior of a magnetically suspended rotor that is distinctly different from that predicted using a simple linearized model. Therefore, the nonlinearities should be taken into account. This literature review is focused on the nonlinear dynamics of magnetic bearing systems and it provides background information on analytical methods, nonlinear vibrations resulting from a rotor contacting auxiliary bearings, and other active topics of research involving the nonlinear properties of magnetic bearing systems, such as nonlinear self-sensing magnetic bearings and nonlinear control of magnetic bearings. The review concludes with a brief discussion on current and possible future directions for research on the nonlinear dynamics of magnetic bearing systems. © 2008 SAGE Publications.

Jiang, ZY, Tang, J, Tieu, AK, Sun, W & Wei, D 2008, 'Surface roughness micro-deformation and transfer of bulk steel in hot rolling', International Journal of Surface Science and Engineering, vol. 2, no. 1/2, pp. 139-139.
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Jiang, ZY, Wei, DB, Li, HJ, Xie, HB, Zhu, HT, Tieu, AK, Liu, XH & Zhang, XM 2008, 'Contact mechanics in cold rolling of thin strip', Suxing Gongcheng Xuebao/Journal of Plasticity Engineering, vol. 15, no. 3, pp. 164-173.
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Cold rolling of thin strip is a challenge in rolling practice, which involves the contact mechanics, strip crown and the surface finish. Using a developed modified influence function method, the cold rolling of thin strip in both symmetric and asymmetric cases were analysed with considering work roll edge contact. This paper addresses the cold rolling of thin strip to justify the roll bite contact mechanics, and to analyse the effects of the friction in the roll bite on rolling mechanics and strip crown. The effects of roll edge contact on rolling mechanics and strip crown are also discussed. Roll edge contact will affect the wear of work roll edge, and the calculated rolling forces are compared with the measured values.

Kirchner, N, Hordern, D, Liu, D & Dissanayake, G 2008, 'Capacitive sensor for object ranging and material type identification', SENSORS AND ACTUATORS A-PHYSICAL, vol. 148, no. 1, pp. 96-104.
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This paper presents a system for object ranging and material type identification using a multifrequency approach for a capacitive sensor. It is shown through an experimental study that the deviation in the readings taken at different sensor drive frequencies and the variation in consecutive readings provide sufficient information to distinguish a range of material types commonly found in a number of environments. A supervised learning scheme is used to classify the material type of planar patches. Extensive experimental evidence is presented to demonstrate the potential of the system. The capacitive based, object penetrating, material type identification is targeted for use with an autonomous robotic system for steel bridge maintenance; significantly different interaction is required for each of the various materials present. Experimental results demonstrate that the information from the sensor is sufficient to range and identify the material type (via physical properties) of an object present in a scene where a bridge structure is being grit-blasted. © 2008 Elsevier B.V. All rights reserved.

Lau, H, Huang, S & Dissanayake, G 2008, 'Discounted MEAN bound for the optimal searcher path problem with non-uniform travel times', EUROPEAN JOURNAL OF OPERATIONAL RESEARCH, vol. 190, no. 2, pp. 383-397.
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We consider an extension of the optimal searcher path problem (OSP), where a searcher moving through a discretised environment may now need to spend a non-uniform amount of time travelling from one region to another before being able to search it for the presence of a moving target. In constraining not only where but when the search of each cell can take place, the problem more appropriately models the search of environments which cannot be easily partitioned into equally sized cells. An existing OSP bounding method in literature, the MEAN bound, is generalised to provide bounds for solving the new problem in a branch and bound framework. The main contribution of this paper is an enhancement, discounted MEAN (DMEAN), which greatly tightens the bound for the new and existing problems alike with almost no additional computation. We test the new algorithm against existing OSP bounding methods and show it leads to faster solution times for moving target search problems. © 2007 Elsevier B.V. All rights reserved.

Li, H, Han, J, Pi, H, Jiang, Z, Wei, D & Tieu, AK 2008, 'Modeling texture development during cold rolling of IF steel by crystal plasticity finite element method', Journal of University of Science and Technology Beijing, Mineral, Metallurgy, Material, vol. 15, no. 6, pp. 696-701.
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With the consideration of slip deformation mechanism and various slip systems of body centered cubic (BCC) metals, Taylor-type and finite element polycrystal models were embedded into the commercial finite element code ABAQUS to realize crystal plasticity finite element modeling, based on the rate dependent crystal constitutive equations. Initial orientations measured by electron backscatter diffraction (EBSD) were directly input into the crystal plasticity finite element model to simulate the development of rolling texture of interstitial-free steel (IF steel) at various reductions. The modeled results show a good agreement with the experimental results. With increasing reduction, the predicted and experimental rolling textures tend to sharper, and the results simulated by the Taylor-type model are stronger than those simulated by finite element model. Conclusions are obtained that rolling textures calculated with 48 {110}< 111 >+{112}< 111 >+{123}< 111 > slip systems are more approximate to EBSD results. (C) 2008 University of Science and Technology Beijing. All rights reserved.

Luo, J, Luo, Z, Chen, L, Tong, L & Wang, MY 2008, 'A semi-implicit level set method for structural shape and topology optimization', Journal of Computational Physics, vol. 227, no. 11, pp. 5561-5581.
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This paper proposes a new level set method for structural shape and topology optimization using a semi-implicit scheme. Structural boundary is represented implicitly as the zero level set of a higher-dimensional scalar function and an appropriate time-ma

Luo, J, Luo, Z, Chen, S, Tong, L & Wang, MY 2008, 'A new level set method for systematic design of hinge-free compliant mechanisms', Computer Methods in Applied Mechanics and Engineering, vol. 198, no. 2, pp. 318-331.
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This paper presents a new level set-based method to realize shape and topology optimization of hinge-free compliant mechanisms. A quadratic energy functional used in image processing applications is introduced in the level set method to control the geometric width of structural components in the created mechanism. A semi-implicit scheme with an additive operator splitting (AOS) algorithm is employed to solve the Hamilton-Jacobi partial differential equation (PDE) in the level set method. The design of compliant mechanisms is mathematically represented as a general non-linear programming with a new objective function augmented by the high-order energy term. The structural optimization is thus changed to a numerical process that describes the design as a sequence of motions by updating the implicit boundaries until the optimized structure is achieved under specified constraints. In doing so, it is expected that numerical difficulties such as the Courant-Friedrichs-Lewy (CFL) condition and periodically applied re-initialization procedures in most conventional level set methods can be eliminated. In addition, new holes can be created inside the design domain. The final mechanism configurations consist of strip-like members suitable for generating distributed compliance, and solving the de-facto hinge problem in the design of compliant mechanisms. Two widely studied numerical examples are studied to demonstrate the effectiveness of the proposed method in the context of designing distributed compliant mechanisms. © 2008 Elsevier B.V. All rights reserved.

Luo, Q & Tong, L 2008, 'Analytical solutions for adhesive composite joints considering large deflection and transverse shear deformation in adherends', International Journal of Solids and Structures, vol. 45, no. 22-23, pp. 5914-5935.
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Luo, Z & Tong, L 2008, 'A level set method for shape and topology optimization of large‐displacement compliant mechanisms', International Journal for Numerical Methods in Engineering, vol. 76, no. 6, pp. 862-892.
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AbstractA parameterization level set method is presented for structural shape and topology optimization of compliant mechanisms involving large displacements. A level set model is established mathematically as the Hamilton–Jacobi equation to capture the motion of the free boundary of a continuum structure. The structural design boundary is thus described implicitly as the zero level set of a level set scalar function of higher dimension. The radial basis function with compact support is then applied to interpolate the level set function, leading to a relaxation and separation of the temporal and spatial discretizations related to the original partial differential equation. In doing so, the more difficult shape and topology optimization problem is now fully parameterized into a relatively easier size optimization of generalized expansion coefficients. As a result, the optimization is changed into a numerical process of implementing a series of motions of the implicit level set function via an existing efficient convex programming method. With the concept of the shape derivative, the geometrical non‐linearity is included in the rigorous design sensitivity analysis to appropriately capture the large displacements of compliant mechanisms. Several numerical benchmark examples illustrate the effectiveness of the present level set method, in particular, its capability of generating new holes inside the material domain. The proposed method not only retains the favorable features of the implicit free boundary representation but also overcomes several unfavorable numerical considerations relevant to the explicit scheme, the reinitialization procedure, and the velocity extension algorithm in the conventional level set method. Copyright © 2008 John Wiley & Sons, Ltd.

Luo, Z, Tong, L & Wang, MY 2008, 'Design of distributed compliant micromechanisms with an implicit free boundary representation', Structural and Multidisciplinary Optimization, vol. 36, no. 6, pp. 607-621.
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In this paper, a parameterization approach is presented for structural shape and topology optimization of compliant mechanisms using a moving boundary representation. A level set model is developed to implicitly describe the structural boundary by embedd

Luo, Z, Wang, MY, Wang, S & Wei, P 2008, 'A level set‐based parameterization method for structural shape and topology optimization', International Journal for Numerical Methods in Engineering, vol. 76, no. 1, pp. 1-26.
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AbstractThis paper presents an effective parametric approach by extending the conventional level set method to structural shape and topology optimization using the compactly supported radial basis functions (RBFs) and the optimality criteria (OC) method. The structural design boundary is first represented implicitly by embedding into a higher‐dimensional level set function as its zero level set, and the RBFs of a favorable smoothness are then applied to interpolate the level set function. The original initial value problem is thus converted to a parametric optimization, with the expansion coefficients of the interplant posed as the design variables.The OC method is then applied to advance the structure boundary in terms of the velocity field derived from the parametric optimization. Hence, the structural shape and topology optimization is now transformed into a process of iteratively finding coefficients to update the level set function to achieve an optimal configuration. The numerical considerations of the conventional level set method, including upwind schemes, velocity extension, and reinitialization, are eliminated. The proposed scheme is capable of addressing structural shape fidelity and topology change simultaneously and of keeping the boundary smooth during the optimization process. Furthermore, numerical convergence is expected to be improved. A widely investigated example, in the framework of structural stiffness designs, is applied to demonstrate the efficiency and accuracy of the proposed approach. Copyright © 2007 John Wiley & Sons, Ltd.

Miro, JV, Taha, T, Wang, D & Dissanayake, G 2008, 'An adaptive manoeuvring strategy for mobile robots in cluttered dynamic environments', International Journal of Automation and Control, vol. 2, no. 2/3, pp. 178-178.
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A novel method which combines an optimised global path planner with a real-time sensor-based collision avoidance mechanism to accommodate for dynamic changes in the environment (e.g., people) is presented. The basic concept is to generate a continually changing parameterised family of virtual force fields for the robot based on characteristics such as location, travelling speed and dimension of the objects in the vicinity, static and dynamic. The interactions among the repulsive forces associated with the various obstacles provide a natural way for local collision avoidance in a partially known cluttered environment. This is harnessed by locally modifying the planned behaviour of the moving platform in real-time, whilst preserving the optimised nature of the global path. Furthermore, path traversability is continually monitored by the global planner to trigger a complete path re-planning from the current location in case of major changes, most notably when the path is completely blocked by obstacles. Copyright © 2008, Inderscience Publishers.

Nguyen, AD, Ngo, VT, Ha, QP & Dissanayake, G 2008, 'Robotic formation: initialisation, trajectory planning and decentralised control', International Journal of Automation and Control, vol. 2, no. 1, pp. 22-22.
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Coordination of a group of mobile robots in desired formations requires an integration of motion planning and control strategies subject to communication bandwidth limitations. An architecture combining virtual structure and leader following techniques is proposed in this paper. The robots are initialised using a new Virtual Robot (VR) tracking and l-l control framework to establish an arbitrary formation without singularities involved and inter-robot collision. Path planning is performed using the modified A* search, coupled with a proposed smoothing technique to generate feasible trajectories with mobile robots, dynamic and kinematic constraints taken into account. Safe trajectories are obtained based on the predefined formation configuration and the given workspace, where obstacles are avoided by adjusting robot trajectories or by changing formation of the robots appropriately. To accommodate the restriction in information exchange, a decentralised approach is proposed to implement the global feedback controller for the formation by using linear functional observers. The proposed architecture is tested through simulation and experiments to verify its validity. Copyright © 2008, Inderscience Publishers.

O’Reilly, L, Horan, K, McNally, PJ, Bennett, NS, Cowern, NEB, Lankinen, A, Sealy, BJ, Gwilliam, RM, Noakes, TCQ & Bailey, P 2008, 'Constraints on micro-Raman strain metrology for highly doped strained Si materials', Applied Physics Letters, vol. 92, no. 23, pp. 233506-233506.
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Ultraviolet (UV), low penetration depth, micro-Raman spectroscopy, and high-resolution x-ray diffraction (HRXRD) are utilized as complementary, independent stress characterization tools for a range of strained Si samples doped by low energy (2keV) Sb ion implantation. Following dopant implantation, good agreement is found between the magnitudes of strain measured by the two techniques. However, following dopant activation by annealing, strain relaxation is detected by HRXRD but not by micro-Raman. This discrepancy mainly arises from an anomalous redshift in the Si Raman peak position originating from the high levels of doping achieved in the samples. This has serious implications for the use of micro-Raman spectroscopy for strain characterization of highly doped strained Si complementary metal-oxide semiconductor devices and structures therein. We find a direct correlation between the Si Raman shift and peak carrier concentration measured by the differential Hall technique, which indicates that UV micro-Raman may become a useful tool for nondestructive dopant characterization for ultrashallow junctions in these Si-based materials.

Petzelt, D, Wischniewski, S, Deuse, J & Helsper, T 2008, 'Use of methods of the digital factory for potential analysis', STAHL UND EISEN, vol. 128, no. 4, pp. 101-104.

Sola, J, Monin, A, Devy, M & Vidal-Calleja, T 2008, 'Fusing Monocular Information in Multicamera SLAM', IEEE Transactions on Robotics, vol. 24, no. 5, pp. 958-968.
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This paper explores the possibilities of using monocular simultaneous localization and mapping (SLAM) algorithms in systems with more than one camera. The idea is to combine in a single system the advantages of both monocular vision (bearings-only, infinite range observations but no 3-D instantaneous information) and stereovision (3-D information up to a limited range). Such a system should be able to instantaneously map nearby objects while still considering the bearing information provided by the observation of remote ones. We do this by considering each camera as an independent sensor rather than the entire set as a monolithic supersensor. The visual data are treated by monocular methods and fused by the SLAM filter. Several advantages naturally arise as interesting possibilities, such as the desynchronization of the firing of the sensors, the use of several unequal cameras, self-calibration, and cooperative SLAM with several independently moving cameras. We validate the approach with two different applications: a stereovision SLAM system with automatic self-calibration of the rig's main extrinsic parameters and a cooperative SLAM system with two independent free-moving cameras in an outdoor setting. © 2008 IEEE.

Zhou, W, Miro, JV & Dissanayake, G 2008, 'Information-Efficient 3-D Visual SLAM for Unstructured Domains', IEEE TRANSACTIONS ON ROBOTICS, vol. 24, no. 5, pp. 1078-1087.
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This paper presents a novel vision-based sensory package and an information-efficient simultaneous localization and mapping (SLAM) algorithm. Together, we offer a solution for building 3-D dense map in an unknown and unstructured environment with minimal computational costs. The sensory package we adopt consists of a conventional camera and a range imager, which provide range and bearing and elevation inputs as commonly used by 3-D feature-based SLAM. In addition, we propose an algorithm to give the robots the 'intelligence' to select, out of the steadily collected data, the maximally informative observations to be used in the estimation process. We show that, although the actual evaluation of information gain for each frame introduces an additional computational cost, the overall efficiency is significantly increased by keeping the matrix compact. The noticeable advantage of this strategy is that the continuously gathered data are not heuristically segmented prior to being input to the filter. Quite the opposite, the scheme lends itself to be statistically optimal and is capable of handling large datasets collected at realistic sampling rates. © 2008 IEEE.

Alempijevic, A, Kodagoda, S & Dissanayake, G 1970, 'Sensor registration for robotic applications', FIELD AND SERVICE ROBOTICS: RESULTS OF THE 6TH INTERNATIONAL CONFERENCE, International Conference on Field and Service Robotics, Springer, France, pp. 233-242.
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Multi-sensor data fusion plays an essential role in most robotic applications. Appropriate registration of information from different sensors is a fundamental requirement in multi-sensor data fusion. Registration requires significant effort particularly when sensor signals do not have direct geometric interpretations, observer dynamics are unknown and occlusions are present. In this paper, we propose Mutual Information (MI) based sensor registration which exploits the effect of a common cause in the observed space on the sensor outputs that does not require any prior knowledge of relative poses of the observers. Simulation results are presented to substantiate the claim that the algorithm is capable of registering the sensors in the presence of substantial observer dynamics. © 2008 Springer-Verlag Berlin Heidelberg.

Aubrey, TA & Aboura, K 1970, 'Bandwidth utilisation for volume-to-volume UWB MIMO communications', 2008 3rd International Symposium on Wireless Pervasive Computing, 2008 3rd International Symposium on Wireless Pervasive Computing (ISWPC), IEEE, Santorini, Greece, pp. 88-92.
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Previous studies have investigated communications between regions of space and have considered the effect of antenna volume in determining the theoretical capacity of multiple-input multiple-output (MIMO) communications systems. In this paper the effects of antenna 1volume on available bandwidth for MIMO systems is considered. It is demonstrated that while higher order modal connections can be established even for small antennas that a fundamental limitation on bandwidth exists. This limitation becomes important for ultra-wide band (UWB) communications systems. © 2008 IEEE.

Behrens, M, Carmichael, M & Patel, M 1970, 'Designing SANDRA: An autonomous tour guide robot for the University of Technology, Sydney', Proceedings of the 2008 Australasian Conference on Robotics and Automation, ACRA 2008, Australasian Conference on Robotics and Automation, Australian Robotics and Automation Association, Canberra, pp. 1-7.
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This paper describes how a team of final year mechatronic engineering students developed an autonomous robotic system intended to act as a tour guide during events such as University open days and explores the opportunities this project presented to extend their knowledge and skills. The specifications of the project required the system to localise and navigate autonomously within a known environment while avoiding collisions with any people or obstacles not included in the prior area map. In addition to these requirements, the system needed to locate humans as potential clients, approach and greet them, offer directions and if required take the guest on a guided tour of the university. While taking the subject Advanced Robotics the students were able to develop a functional first prototype of the system and carry out initial tests. Following the completion of the subject a small number of the students opted to continue working on the project developing a second prototype using the knowledge gained and further enhancing their learning experiences. While this project mainly involved integrating existing well known algorithms, software and hardware, it provided an excellent opportunity to enhance the mechatronic engineering skills of the students involved.

Bennett, NS, Cowern, NEB, Paul, S, Lerch, W, Kheyrandish, H, Smith, AJ, Gwilliam, R & Sealy, BJ 1970, 'Vacancy engineering for highly activated &#x2018;diffusionless&#x2019; boron doping in bulk silicon', ESSDERC 2008 - 38th European Solid-State Device Research Conference, ESSDERC 2008 - 38th European Solid-State Device Research Conference, IEEE, Edinburgh, SCOTLAND, pp. 290-+.
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Bright, C, Lindsay, E, Lowe, DB, Murray, SJ & Liu, D 1970, 'Factors That Impact Learning Outcomes in Both Simulation and Remote Laboratories', Ed-Media 2008: World Conference on Educational Multimedia, Hypermedia and Telecommunications, Educational Multimedia, Hypermedia & Telecommunications, AACE, Vienna, Austria, pp. 6251-6258.

Carelli, MD, Mycoff, CW, Garrone, P, Locatelli, G, Mancini, M, Ricotti, ME, Trianni, A & Trucco, P 1970, 'Competitiveness of Small-Medium, New Generation Reactors: A Comparative Study on Capital and O&M Costs', Volume 4: Structural Integrity; Next Generation Systems; Safety and Security; Low Level Waste Management and Decommissioning; Near Term Deployment: Plant Designs, Licensing, Construction, Workforce and Public Acceptance, 16th International Conference on Nuclear Engineering, ASMEDC, Orlando, FL, pp. 499-506.
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Smaller size reactors are going to be an important component of the worldwide nuclear renaissance. An inappropriate application of the economy of scale would label the small-medium size reactors as not economically competitive with larger plants because of capital costs ($/kWe) and O&M costs ($/kWh) that would appear to be significantly higher. However, the economy of scale applies only if the considered designs are similar, which is not the case here, since the small size allows original design solutions not accessible to large size reactors. In the paper the historical trend of capital costs vs. plant size is estimated from literature, and a reference exponent factor for the economy of scale for the light water reactor is derived. Then the paper identifies and briefly discusses the various factors which, beside size, contribute in differentiating the capital cost of smaller reactors with respect to large reactors. In this reference frame the evaluation for of the following factors is provided: · design characteristics · modular build · multiple units · accelerated learning in construction · operation, and shorter construction time. The IRIS reactor is used as the example of small modular reactor (SMR), but the analysis and conclusions are applicable to the whole spectrum of small nuclear plants. The results show that when all these factors are accounted for in a set of realistic and comparable configurations, and with the same power installed in the site, the capital costs of small and large plants installations are practically equivalent. Considering the O&M cost the paper shows how the plant size is not the only and fundamental cost driver. In fact there is a range of other factors (e.g. location, regulatory issues, capacity factor, plant obsolescence and number of reactors on a site) able to influence the annual O&M cost for a specific plant. The paper provides a preliminary evaluation of these factors by historical analysis of ...

Chotiprayanakul, P, Wang, D, Kwok, N & Liu, D 1970, 'A haptic base Human Robot Interaction approach for robotic grit blasting', 25TH INTERNATIONAL SYMPOSIUM ON AUTOMATION AND ROBOTICS IN CONSTRUCTION - ISARC-2008, International Symposium on Automation and Robotics in Construction, IAARC, Vilnius, Lithuania, pp. 148-154.
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This paper proposes a remote operation method for a robot arm in a complex environment by using the Virtual Force (VF) based approach. A virtual robot arm is manipulated by a steering force, at the end-effecter, which is generated according to the movement of a feedback haptic. A three-dimensional force field (3D-F2) is employed in collision detection and avoidance. Repulsive forces from the 3D-F2 are produced and feedback to the haptic device that enables the operator to have a sense of touch on the encountered obstacle and then steer the arm to avoid it. As a result, collision-free poses of the virtual robot arm can then be used to command the real robot. Experiments are conducted in a mock up bridge environment where the real robot arm is steered to target points by the operator. Experiment results have shown successful collision avoidance and emulation of the actual command force and the virtual forces in remote operations.

Chotiprayanakul, P, Wang, D, Kwok, N & Liu, D 1970, 'A Haptic Base Human Robot Interaction Approach for Robotic Grit Blasting', ISARC 2008 - Proceedings from the 25th International Symposium on Automation and Robotics in Construction, 25th International Symposium on Automation and Robotics in Construction, International Association for Automation and Robotics in Construction (IAARC).
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Clifton, M, Paul, G, Kwok, N, Liu, D, Wang, D-L & IEEE 1970, 'Evaluating Performance of Multiple RRTs', PROCEEDINGS OF 2008 IEEE/ASME INTERNATIONAL CONFERENCE ON MECHATRONIC AND EMBEDDED SYSTEMS AND APPLICATIONS, American Society of Mechanical Engineering, IEEE, Beijing, China, pp. 564-569.
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This paper presents experimental results evaluating the performance of a new multiple Rapidly-exploring Random Tree (RRT) algorithm. RRTs are randomised planners especially adept at solving difficult, high-dimensional path planning problems. However, environments with low-connectivity due to the presence of obstacles can severely affect convergence. Multiple RRTs have been proposed as a means of addressing this issue, however, this approach can adversely affect computational efficiency. This paper introduces a new and simple method which takes advantage of the benefits of multiple trees, whilst ensuring the computational burden of maintaining them is minimised. Results indicate that multiple RRTs are able to reduce the logarithmic complexity of the search, most notably in environments with high obstacle densities. © 2008 IEEE.

Gibson, T, Thai, K, Saxon, J & Pollock, R 1970, 'The effectiveness of safety equipment in horse racing falls', International Research Council on the Biomechanics of Injury - 2008 International IRCOBI Conference on the Biomechanics of Injury, Proceedings, pp. 453-456.
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The effectiveness of the personal protective equipment PPE used by jockeys and harness drivers in falls during racing was investigated. In Australia the wearing of helmets and protective vests is mandatory in both forms of the sport, though the equipment standards differ. The incidence of injury was analysed and the mechanisms of injury investigated by video analysis of actual injury incidents. The effectiveness of the safety equipment was assessed through physical testing. The differing injury mechanisms and track surfaces in the two sports result in unique requirements for the protective equipment used. The needs for future development of improved equestrian personal protective equipment are outlined.

Herath, DC, Kodagoda, S, Dissanayake, G & IEEE 1970, 'New framework for simultaneous localization and mapping: Multi map SLAM', 2008 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS 1-9, IEEE International Conference on Robotics and Automation, IEEE, Pasadena, California, pp. 1892-1897.
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The main contribution of this paper arises from the development of a new framework, which has its inspiration in the mechanics of human navigation, for solving the problem of Simultaneous Localization and Mapping (SLAM). The proposed framework has specific relevance to vision based SLAM, in particular, small baseline stereo vision based SLAM and addresses several key issues relevant to the particular sensor domain. Firstly, as observed in the authors' earlier work, the particular sensing device has a highly nonlinear observation model resulting in inconsistent state estimations when standard recursive estimators such as the Extended Kalman Filter (EKF) or the Unscented variants are used. Secondly, vision based approaches tend to have issues related to large feature density, narrow field of view and the potential requirement of maintaining large databases for vision based data association techniques. The proposed Multi Map SLAM solution addresses the filter inconsistency issue by formulating the SLAM problem as a nonlinear batch optimization. Feature management is addressed through a two tier map representation. The two maps have unique attributes assigned to them. The Global Map (GM) is a compact global representation of the robots environment and the Local Map (LM) is exclusively used for low-level navigation between local points in the robot's navigation horizon. ©2008 IEEE.

Huang, S, Wang, Z, Dissanayake, G & Frese, U 1970, 'Iterated SLSJF: A sparse local submap joining algorithm with improved consistency', Proceedings of the 2008 Australasian Conference on Robotics and Automation, ACRA 2008, Australasian Conference on Robotics and Automation, ARAA, Canberra, Australia, pp. 1-9.
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This paper presents a new local submap joining algorithm for building large-scale feature based maps. The algorithm is based on the recently developed Sparse Local Submap Joining Filter (SLSJF) and uses multiple iterations to improve the estimate and hence is called Iterated SLSJF (I-SLSJF). The input to the I-SLSJF algorithm is a sequence of local submaps. The output of the algorithm is a global map containing the global positions of all the features as well as all the robot start/end poses of the local submaps. In the submap joining step of I-SLSJF, whenever the change of state estimate computed by an Extended Information Filter (EIF) is larger than a predefined threshold, the information vector and the information matrix is recomputed as a sum of all the local map contributions. This improves the accuracy of the estimate as well as avoids the possibility that the Jacobian with respect to the same feature gets evaluated at different estimate values, which is one of the major causes of inconsistency for EIF/EKF algorithms. Although the computational cost of I-SLSJF is higher than that of SLSJF, the algorithm can still be implemented effciently due to the exactly sparseness of the information matrix. The new algorithm is compared with EKF SLAM and SLSJF using both computer simulation and experimental examples.

Huang, S, Wang, Z, Dissanayake, G & IEEE 1970, 'Exact state and covariance sub-matrix recovery for submap based sparse EIF SLAM algorithm', 2008 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS 1-9, IEEE International Conference on Robotics and Automation, IEEE, Pasadena, California, pp. 1868-1873.
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This paper provides a novel state vector and covariance sub-matrix recovery algorithm for a recently developed submap based exactly sparse Extended Information Filter (EIF) SLAM algorithm - Sparse Local Submap Joining Filter (SLSJF). The algorithm achieves exact recovery instead of approximate recovery. The recovery algorithm is very efficient because of an incremental Cholesky factorization approach and a natural reordering of the global state vector. Simulation results show that the computation cost of the SLSJF is much lower as compared with the sequential map joining algorithm using Extended Kalman Filter (EKF). The SLSJF with the proposed recovery algorithm is also successfully applied to the Victoria Park data set. ©2008 IEEE.

Huynh, BP 1970, 'Numerical investigation of effects of two-dimensional thermal plumes on cross-flow', 9th National Conference on Hydraulics in Water Engineering 2008, National Conference on Hydraulics in Water Engineering, Engineers Australia, Darwin, Northern Territory, Australia, pp. 1-7.
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Numerical investigation of the effects of thermal plumes rising from a heated horizontal plate positioned on the floor in a cross-flow is conducted, using a commercial Computational Fluid Dynamics (CFD) software package. A two-dimensional flow configuration of fresh water is assumed, and the low-Reynolds-number turbulence model of Chien is used. The effects are characterised by an angle θ above the horizontal of the interface between the original cross-flow and a second, negative cross-flow that is induced from downstream of the plate. It is shown that θ correlates quite well with the cross-flow Froude number Fr, decreasing linearly with a mild slope (on a log-linear plot) with increasing Fr, when this is less than about 0.08. A sharp drop of θ follows, to reach and remain at zero, for Fr larger than about 0.1. This study thus shows that at low Fr, cross-flow can not reach large regions of the flow field. The situation is reversed when Fr is larger than about 0.1; then, the cross-flow reaches virtually all parts of the flow field.

Jiang, Z & Wei, D 1970, 'Asymmetric rolling of thin strip with work roll edge kiss', AES-ATEMA International Conference Series - Advances and Trends in Engineering Materials and their Applications, pp. 189-193.
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Asymmetric rolling can reduce strip thickness significantly. When the thinner strip is rolled in a cold strip mill, the work roll edge may kiss each other. Work roll edge kiss affects the mechanics of asymmetric rolling and the crown of the rolled strip significantly, which has not been quantified before. In this paper, the numerical simulation has been carried out to analyse the asymmetric rolling of thin strip with roll edge kiss when a cross shear region exists in the roll bite. The rolling force, roll edge kiss force and the strip crown for asymmetric rolling of thin strip are discussed. The calculated crown of the rolled strip is compared with the measured value. Effect of the friction on the roll edge kiss length is also discussed. © AES-Advanced Engineering Solutions.

Jiang, ZY, Li, HJ, Han, JT, Wei, DB, Pi, HC & Tieu, AK 1970, 'Crystal plasticity finite element modelling of compression of pure aluminum', Civil-Comp Proceedings.
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In order to compare the influence of the different finite element models on the experimental results, Taylor-Type and finite element polycrystalline models are separately employed in the finite element software ABAQUS to simulate the development of the deformation texture by rate dependent crystal constitutive equations during the uniaxial tensile deformation. Initial orientations measured by backscatter diffraction (EBSD) are directly input into the crystal plasticity finite element model. With the increase of true strain, the crystal can rotate and the silk textures form easily, therefore the predicted and experimental silk textures tend to sharper and stronger accordingly. There is only one kind of silk texture (<110> texture) formed in the uniaxial compression. Comparison of the contouring map with different strains, the finite element polycrystalline model can accurately predict the drum deformation of pure aluminum during the uniaxial compression. © Civil-Comp Press, 2008.

Jiang, ZY, Tang, J, Tieu, AK & Wei, D 1970, 'Simulation of oxide scale cracks in hot strip rolling', 9th International Conference on Technology of Plasticity, ICTP 2008, pp. 654-659.
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In this paper, the behavior of oxide scale cracks and its surface roughness in hot strip rolling are simulated using finite element software MSC-MARC package. A model generating surface roughness profile that remains well the random characteristics of surface roughness and asperity was applied in this study. The characteristics of oxide scale cracks with various crack aspect ratios is investigated, and the deformation features of surface roughness of the oxide scale and steel are obtained from the finite element simulation. The developed model of oxide scale crack is helpful for further understanding the mechanics of the change of oxide scale cracks in the roll bite and for improving the steel strip surface quality.

Jiang, ZY, Wei, D, Zhu, H & Tieu, KA 1970, 'Mechanics of cold rolling of ultra thin strip with work roll edge kiss', Steel Research International, 12th International Conference on Metal Forming, Verlag Stahleisen Mbh, Cracow, POLAND, pp. 764-771.
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In this paper, the cold rolling experiments of ultra thin steel strip were carried out on a Hille-100 experimental rolling mill, and theoretical analysis of cold rolling of the strip with roll edge kiss has been conducted. Simulation results show that the reduction has a significant influence on the crown of rolled strip, and the calculated rolling forces and strip crown are consistent with the measured values. The effect of friction in the roll bite on mechanics of cold rolling of ultra thin strip with roll edge kiss is also discussed. Surface characteristic was measured by a Hommel Tester T1000 portable profilemeter. It can be concluded that the strip surface roughness value decreases significantly after cold rolling. Thus the surface finish becomes better after cold rolling of ultra thin strip. © 2008 Verlag Stahleisen GmbH, Düsseldorf.

JIANG, ZY, WEI, DW & TIEU, AK 1970, 'AN INFLUENCE FUNCTION METHOD ANALYSIS OF COLD STRIP ROLLING', International Journal of Modern Physics B, 9th Asia-Pacific Symposium on Engineering Plasticity and Its Applications (AEPA 2008), World Scientific Pub Co Pte Lt, Daejeon, SOUTH KOREA, pp. 5728-5733.
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An influence function method has been developed to simulate the asymmetric cold rolling of thin strip with work roll kiss at edges. The numerical simulation model was obtained based on the deformation compatibility of the roll system in rolling and lateral directions. The strip plastic deformation has been considered in the formulation, which is significantly different from the traditional theory of metal rolling. The rolling mechanics and crown of the strip with work roll edge kiss, which are new findings for cold rolling of thin strip, are obtained. A comparison of the rolling force, roll edge kiss force and the strip crown after rolling has been conducted for various cross shear regions in the roll bite. Results show that the calculated strip crown is in good agreement with Ameasured value, and the rolling force and strip crown decrease with an increase of cross shear regions, as well as the work roll edge kiss force and edge wear decrease. The friction also has an influence on the profile of the rolled thin strip.

Kodagoda, S, Zhang, Z, Ruiz, D & Dissanayake, G 1970, 'Sensing and Classification for Autonomous Weed Control', The IEEE International Conference on Robotics and Automation (ICRA 2008), workshop, IEEE International Conference on Robots and Automation, IEEE explorer, Pasadena, California, pp. 1-6.
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Autonomous weed control concepts have recently being extensively researched due to the advantages that they possess. One of the critical modules of such systems is the sensing and classification of weeds within crops. In this paper, we systematically chose the sensing setup and cues to be used for classification of two common weed species (Bidens pilosa L. and Lolium rigidum L.) in a wheat crop. An automatic cue selection procedure is proposed. Some classification results and their problems were discussed leading to future direction of research.

Kodagoda, S, Zhang, Z, Ruiz, D & Dissanayake, G 1970, 'Weed detection and classification for autonomous farming', Proceedings of Fourth I*PROMS Virtual International Conference, Intelligent Production Machines and Systems, I*PROMS, Cardiff, UK, pp. 1-6.
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Autonomous weed control concepts have recently being extensively researched due to the advantages that they possess. One of the critical modules of such systems is the sensing and classification of weeds within crops. In this paper, we systematically chose the sensing setup and cues to be used for classification of two common weed species (Bidens pilosa L. and Lolium rigidum L.) in a wheat crop. An automatic cue selection followed by classification procedure is proposed. Some classification results are presented while discussing problems leading to future direction of research.

Kreimeyer, M, Braun, S, Gu¨rtler, M & Lindemann, U 1970, 'Relating Two Domains via a Third: An Approach to Overcome Ambiguous Attributions Using Multiple Domain Matrices', Volume 1: 34th Design Automation Conference, Parts A and B, ASME 2008 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, ASMEDC, pp. 297-306.
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Design Structure Matrices (DSM) and Domain Mapping Matrices (DMM) are commonly used to model and analyze the relationships within one domain (DSM) or between two domains (DMM). Being assembled into one larger square matrix, having DSMs on its diagonal and DMMs in all other fields, a so-called Multiple Domain Matrix (MDM) is formed. When relating two domains using a DMM, a problem arises when the nature of one individual relationship between the two domains is to be described. Usually, this is modeled by annotating each relationship with the additional information, much like comments in spreadsheet software. This, however, is yet impossible if the relationships should be in matrix notation to allow for algorithmic matrix analyses. Equally, this way, the annotations are not accessible as elements of another matrix, e.g. as DSM. This paper suggests a generic principle to solve the described problem in a way consistent with the matrix methodology. It proposes an approach using MDM and is thereby able to unambiguously provide the nature of each relationship between the elements of two domains. As a DSM is a mere case of a DMM having two identical domains, the approach proposed can equally be used to enrich the relationships within a DSM.

Kreimeyer, M, Braun, S, Guertler, MR & Lindemann, U 1970, 'Relating two Domains via a Third – An Approach to Overcome Ambiguous Attributions using Multiple Domain Matrices', Proceedings of the ASME 2008 International Design Engineering Technical Conferences & Computers and Information in Engineering Conference, ASME 2008 International Design Engineering Technical Conferences & Computers and Information in Engineering Conference IDETC/CIE, ASME, New York, pp. 1-11.
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Design Structure Matrices (DSM) and Domain Mapping Matrices (DMM) are commonly used to model and analyze the relationships within one domain (DSM) or between two domains (DMM). Being assembled into one larger square matrix, having DSMs on its diagonal and DMMs in all other fields, a so-called Multiple Domain Matrix (MDM) is formed. When relating two domains using a DMM, a problem arises when the nature of one individual relationship between the two domains is to be described. Usually, this is modeled by annotating each relationship with the additional information, much like comments in spreadsheet software. This, however, is yet impossible if the relationships should be in matrix notation to allow for algorithmic matrix analyses. Equally, this way, the annotations are not accessible as elements of another matrix, e.g. as DSM.This paper suggests a generic principle to solve the described problem in a way consistent with the matrix methodology. It proposes an approach using MDM and is thereby able to unambiguously provide the nature of each relationship between the elements of two domains. As a DSM is a mere case of a DMM having two identical domains, the approach proposed can equally be used to enrich the relationships within a DSM.

Kreimeyer, M, Guertler, MR & Lindemann, U 1970, 'Structural metrics for decision points within Multiple-Domain Matrices representing design processes', 2008 IEEE International Conference on Industrial Engineering and Engineering Management, IEEE, Singapur, pp. 1-5.
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When reengineering or improving an engineering process, it is important to systematically examine the process for possible weak spots. Complexity metrics, which describe how “complex” a possible part of a process is, are a means of doing so. Using them, every single element of a process (e.g. activities, resources,…) or groups of elements can be reviewed, and those exhibiting distinctive features can be further considered for improvement. Such metrics are especially of interest if no quantitative data is available but only the qualitative process architecture is at hand, e.g. as a process chart. In this paper, different metrics from software and workflow engineering (McCabe Complexity, Control-flow Complexity, Activity / Passivity) are used on a qualitative model of a process incorporating decision points. The process model is based on a Multiple-Domain Matrix extended to comprise Boolean operators that are typical for process models (i.e. AND, OR, and XOR).

Kreimeyer, M, Gurtler, M & Lindemann, U 1970, 'Structural metrics for decision points within multiple-domain matrices representing design processes', 2008 IEEE International Conference on Industrial Engineering and Engineering Management, 2008 IEEE International Conference on Industrial Engineering and Engineering Management, IEEE, Singapore, SINGAPORE, pp. 435-439.
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Lau, H, Pratley, T, Liu, D, Huang, S & Pagac, D 1970, 'An implementation of prioritized path planning for a large fleet of autonomous straddle carriers', International Federation of Operational Research Societies (IFORS), Sandton, South Africa.

Leung, C, Huang, S, Dissanayake, G & IEEE 1970, 'Active SLAM in structured environments', 2008 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS 1-9, IEEE International Conference on Robotics and Automation, IEEE, Pasadena, USA, pp. 1898-1903.
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This paper considers the trajectory planning problem for line-feature based SLAM in structured indoor environments. The robot poses and line features are estimated using Smooth and Mapping (SAM) which is found to provide more consistent estimates than the Extended Kalman Filter (EKF). The objective of trajectory planning is to minimise the uncertainty of the estimates and to maximise coverage. Trajectory planning is performed using Model Predictive Control (MPC) with an attractor incorporating long term goals. This planning is demonstrated both in simulation and in a real-time experiment with a Pioneer2DX robot. ©2008 IEEE.

Li, H, Jiang, Z, Han, J, Wei, D, Pi, H & Kiet Tieu, A 1970, 'Crystal plasticity finite element modeling of necking of pure aluminum during uniaxial tensile deformation', Steel Research International, 12th International Conference on Metal Forming, Verlag Stahleisen Mbh, Cracow, POLAND, pp. 655-662.
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In order to figure out the slip deformation mechanisms and slip mechanism of various slip systems, Taylor-Type and finite element polycrystal models are separately input into the finite element software ABAQUS to model the development of the deformation texture during uniaxial tensile deformation. Initial orientation measured by electronic backscatter diffraction (EBSD) was directly input into crystal plasticity finite element model to simulate the necking of aluminum plate during the uniaxial tensile deformation. The results from the two polycrystal models are both approximate to the experimental results. Comparison with the deformation contouring map of the pure aluminum at the different strains, both the two polycrystal models could predict the necking of pure aluminum during the uniaxial tensile deformation, and two kind of silk textures formed in the uniaxial tensile deformation: one <111> silk texture; and the other <100> silk texture. However, the true necking strain and stress of experiments were different from those of two polycrystal models. © 2008 Verlag Stahleisen GmbH, Düsseldorf.

Li, HC, Jiang, ZY, Tieu, AK, Sun, WH, Li, HJ & Wei, DB 1970, 'Surface Roughness and Wear of Work Roll Containing Ti in Cold Strip Rolling', Advanced Materials Research, International Conference on Frontiers in Materials Science and Technology, Trans Tech Publications, Ltd., Queensland Univ Technol, Brisbane, AUSTRALIA, pp. 157-160.
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The consumption of work rolls in cold strip mills is significant. One of the key issues forwork rolls is the surface roughness which affects the rolling stability and surface finish of the strip.The produced strip has lower surface finish if the roll surface roughness is large. However, if theroll surface roughness is small, it is not helpful for establishing the rolling process, which willreduce the productivity. In this case, a laser treatment is employed to increase the value of rollsurface roughness. In order to reduce the times of roll grinding, the cold strip mill and rollmanufacturers have developed new types of rolls such as the rolls containing Ti to increase the rollwear resistance in cold strip rolling. Results show that the new 4CrTi roll has a significantadvantage of preventing decrease of the roll surface roughness. The size and generation of particlesduring roll wear process and the effect of Ti on roll wear have been discussed.

Li, HC, Jiang, ZY, Tieu, AK, Sun, WH, Li, HJ & Wei, DB 1970, 'Surface Roughness and Wear of Work Roll Containing Ti in Cold Strip Rolling', Advanced Materials Research, Trans Tech Publications Ltd., pp. 157-160.
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The consumption of work rolls in cold strip mills is significant. One of the key issues for work rolls is the surface roughness which affects the rolling stability and surface finish of the strip. The produced strip has lower surface finish if the roll surface roughness is large. However, if the roll surface roughness is small, it is not helpful for establishing the rolling process, which will reduce the productivity. In this case, a laser treatment is employed to increase the value of roll surface roughness. In order to reduce the times of roll grinding, the cold strip mill and roll manufacturers have developed new types of rolls such as the rolls containing Ti to increase the roll wear resistance in cold strip rolling. Results show that the new 4CrTi roll has a significant advantage of preventing decrease of the roll surface roughness. The size and generation of particles during roll wear process and the effect of Ti on roll wear have been discussed.

Li, HJ, Han, JT, Jiang, ZY, Pi, HC, Wei, DB & Tieu, AK 1970, 'Crystal Plasticity Finite Element Modelling of BCC Deformation Texture in Cold Rolling', Advanced Materials Research, International Conference on Frontiers in Materials Science and Technology, Trans Tech Publications, Ltd., Queensland Univ Technol, Brisbane, AUSTRALIA, pp. 251-254.
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Taylor-type and finite element polycrstal models have been embedded into the commercialfinite element code ABAQUS to carry out the crystal plasticity finite element modelling of BCCdeformation texture based on rate dependent crystal constitutive equations. Initial orientationsmeasured by EBSD were directly used in crystal plasticity finite element model to simulate thedevelopment of rolling texture of IF steel under various reductions. The calculated results are in goodagreement with the experimental values. The predicted and measured textures tend to sharper with anincrease of reduction, and the texture obtained from the Taylor-type model is much stronger than thatby finite element model. The rolling textures calculated with 48 {110}<110>, {112}<111> and{123}<111> slip systems are close to the EBSD results.

Li, HJ, Han, JT, Jiang, ZY, Pi, HC, Wei, DB & Tieu, AK 1970, 'Crystal Plasticity Finite Element Modelling of BCC Deformation Texture in Cold Rolling', Frontiers In Materials Science And Technology, International Conference on Frontiers in Materials Science and Technology, Trans Tech Publications Ltd., Brisbane, AUSTRALIA, pp. 251-254.
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Taylor-type and finite element polyerstal models have been embedded into the commercial finite element code ABAQUS to carry out the crystal plasticity finite element modelling of BCC deformation texture based on rate dependent crystal constitutive equations. Initial orientations measured by EBSD were directly used in crystal plasticity finite element model to simulate the development of rolling texture of IF steel under various reductions. The calculated results are in good agreement with the experimental values. The predicted and measured textures tend to sharper with an increase of reduction, and the texture obtained from the Taylor-type model is much stronger than that by finite element model. The rolling textures calculated with 48 {110}< 110 >, {112}< 111 > and {123}< 111 > slip systems are close to the EBSD results.

Lindsay, ED, Murray, S, Liu, DK, Lowe, DB & Bright, CG 1970, 'Establishment reality vs Maintenance Reality: How real is real enough?', Proceedings of 36th European Society for Engineering Education, SEFI Conference on Quality Assessment, Employability and Innovation, Annual Conference of European Society for Engineering Education, European Society for Engineering Education, Aarlborg, Denmark, pp. 1-4.
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Remote and virtual laboratories are increasingly prevalent alternatives to the face to face laboratory experience, however the question of their learning outcomes is yet to be fully investigated. There are many presumptions regarding the effectiveness of these approaches; foremost amongst these assumptions is that the experience must be 'real' to be effective. Embedding reality into a remote or virtual laboratory can be an expensive and time consuming task. Significant effort has been expended to create 3D VRML models of laboratory equipment, allowing students to pan, zoom and tilt their perspective as they see fit. Multiple camera angles have be embedded into remote interfaces to provide an increased sense of 'real-ness'. This paper draws upon the literature in the field to show that the necessary threshold for reality varies depending upon how the students are interacting with the equipment. There is one threshold for when they first interact - the Establishment Reality - which allows the students to familiarise themselves with the laboratory equipment, and to build their mental model of the experience. There is, however, a second, lower, threshold - the Maintenance Reality - that is necessary for the students' ongoing operation of the equipment. Students' usage patterns rely upon a limited subset of the available functionality, focussing upon only some aspects of the reality that has been originally established. The two threshold model presented in this paper provides new insight for the development of virtual laboratories in the future.

Liu, DK, Dissayanake, G, Manamperi, PB, Brooks, PA, Fang, G, Paul, G, Webb, S, Kirchner, N, Chotiprayanakul, P, Kwok, NM & Ren, TR 1970, 'A robotic system for steel bridge maintenance: Research challenges and system design', Proceedings of the 2008 Australasian Conference on Robotics and Automation, ACRA 2008, Australasian Conference on Robotics and Automation, Australian Robotics and Automation Association, Australia National University, Canberra, Australia, pp. 1-7.
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This paper presents the research on and development of a robotic system for stripping paint and rust from steel bridges, with the ultimate objective of preventing human exposure to hazardous and dangerous debris (containing rust, paint particles, lead and/or asbestos), relieving human workers from labor intensive tasks and reducing costs associated with bridge maintenance. The robot system design, the key research challenges and enabling technologies and system development are discussed in detail. Research results obtained so far and discussions on some key issues are also presented.

Lowe, DB, Murray, SJ, Lindsay, E, Liu, D & Bright, C 1970, 'Reflecting Professional Reality in Remote Laboratory Experiences', REV 2008: Remote Engineering and Virtual Instrumentation, Remote Engineering and Virtual Instrumentation, International Association of Online Engineering, Dusseldorf, Germany, pp. 1-5.

Lu, C, Wei, D, Jiang, Z & Tieu, K 1970, 'Experimental and theoretical investigation of the asperity flattening process under large bulk strain', Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology, 34th Leeds-Lyon Symposium on Tribology, SAGE Publications, Inst Natl Sci Appliquees, Lyon, FRANCE, pp. 271-278.
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In this paper, the flattening of the model asperities under large bulk strain has been experimentally and theoretically investigated. The specimens with two types of model asperities (pyramid-shaped asperity and ridge-shaped asperity) on the top surface are compressed by a flat punch. The measured contact ratios are used to validate the theoretical model. The rigid-plastic finite-element method model is developed to analyse the asperity flattening processes under bulk straining. The results show that the contact ratio increases with bulk strain and the contact pressure for both types of asperities. The ridge-shaped asperity exhibits a higher contact ratio than the pyramid-shaped asperity. The contact ratio also increases with the asperity angles in the presence of large bulk deformation.

Murray, S, Lowe, D, Lindsay, E, Lasky, V & Liu, D 1970, 'Experiences with a hybrid architecture for remote laboratories', 2008 38th Annual Frontiers in Education Conference, 2008 IEEE Frontiers in Education Conference (FIE), IEEE, Saratgoa Springs, USA, pp. 15-19.
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There is growing interest in the use of remote laboratories to access physical laboratory infrastructure. These laboratories can support additional practical components in courses, provide improved access at reduced cost, and encourage sharing of expensive resources. Effective design of remote laboratories requires attention to both the pedagogic design and the technical support, as well as how these elements interact. We discuss our experiences with a remote laboratory implementation based on a hybrid architecture. This architecture utilises a Web front-end allowing student access to an arbitration system, which permits students to select one of a number of experiments, before being allocated to a particular experimental station. The interaction with the equipment then occurs through a separate stand-alone application which runs on its own virtualized server which the user accesses via a remote desktop client. This hybrid architecture has many benefits, as well as some limitations. For example, it allows rich control and monitoring interfaces to be developed, but also requires students to understand a slightly more complex process for establishing the control. We discuss the reactions to this architecture by different cohorts of students as well as the extent to which the architecture facilitates evolution and expansion of the laboratories. © 2008 IEEE.

Murray, S, Lowe, D, Lindsay, E, Lasky, V, Liu, D & IEEE 1970, 'Experiences with a Hybrid Architecture for Remote Laboratories', FIE: 2008 IEEE FRONTIERS IN EDUCATION CONFERENCE, VOLS 1-3, IEEE Frontiers in Education Conference 2008, IEEE, Saratoga Springs, NY, pp. 502-506.

Neubert, P, Protzel, P, Vidal-Calleja, T & Lacroix, S 1970, 'A fast visual line segment tracker', 2008 IEEE International Conference on Emerging Technologies and Factory Automation, Factory Automation (ETFA 2008), IEEE, Hamburg, GERMANY, pp. 353-360.
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We present a fast line segment tracker which does not require any knowledge about the motion of the camera nor he structure of the observed scene. It runs on 320 x 240 pixel images at 30 Hz. We adapted the RAPiD tracker with a new way of handling multipl

Oberst, S & Lai, JCS 1970, 'New approaches for understanding the mechanisms of brake squeal', Annual Conference of the Australian Acoustical Society, AAS'08, pp. 265-272.
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Brake squeal has become an increasing concern for the automotive industry because of associated warranty costs and the requirement for the continued reduction of interior vehicle noise. Low and high frequency noises in car brakes, often referred to as brake squeal, are known to be a result of nonlinearity, unstable behaviour and bifurcations leading to limit cycle behaviour. By using the data from a separate experimental study designed to determine the influence of the geometric parameters of brake pads (such as the number and location of slots) on brake squeal noise, we examine two new approaches for providing improved understanding of the brake squeal phenomenon: statistical and nonlinear dynamics analyses. Results of the statistical analysis indicate that the performances of certain pad designs correlate with their levels of nonlinearity. The nonlinear time series analysis reveals that, in the experimental data, not only are limit cycle behaviours present but also a route to chaotic solutions can be observed.

Pawlak, BJ, Duffy, R, van Dal, M, Voogt, F, Weemaes, R, Roozeboom, F, Zalm, P, Bennett, N & Cowern, N 1970, 'Doping of Sub-50nm SOI Layers', MRS Proceedings, Symposium on Doping Engineering for Front-End Processing held at the 2008 MRS Spring Meeting, Springer Science and Business Media LLC, San Francisco, CA, pp. 169-+.
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ABSTRACTDoping of thin body Si becomes very essential topic due to increasing interest of forming source/drain regions in fully depleted planar silicon-on-isolator (SOI) devices or vertical Fin field-effect-transistors (FinFETs). To diminish the role of the short-channel-control-effect (SCE) the Si layers thicknesses target the 10 nm range. In this paper many aspects of thin Si body doping are discussed: dopant retention, implantation-related amorphization, thin body recrystallization, sheet resistance (Rs) and carrier mobility in crystalline or amorphized material, impact of the annealing ambient on Rs for various SOI thicknesses. The complexity of 3D geometry for vertical Fin and the vicinity of the extended surface have an impact on doping strategies that are significantly different than for planar bulk devices.

Pedraza, L, Dissanayake, G, Miro, JV, Rodriguez-Losada, D & Matia, F 1970, 'BS-SLAM: Shaping the world', Robotics: Science and Systems, pp. 169-176.
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This paper presents BS-SLAM, a simultaneous localization and mapping algorithm for use in unstructured environments that is effective regardless of whether features correspond to simple geometric primitives such as lines or not. The coordinates of the control points defining a set of B-splines are used to form a complete and compact description of the environment, thus making it feasible to use an extended Kalman filter based SLAM algorithm. The proposed method is the first known EKF-SLAM implementation capable of describing both straight and curve features in a parametric way. Appropriate observation equation that allows the exploitation of virtually all observations from a range sensor such as the ubiquitous laser range finder is developed. Efficient strategies for computing the relevant Jacobians, perform data association, initialization and expanding the map are presented. The effectiveness of the algorithms is demonstrated using experimental data.

Rawtsthorne, D, Jiang, ZY & Wei, D 1970, 'Analysis of cold rolling of ultra thin strip', 9th International Conference on Technology of Plasticity, ICTP 2008, pp. 801-806.
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In this paper, the effects of cold rolling parameters on rolling mechanics and surface roughness of the ultra thin steel strip have been identified. A quantitative experimental methodology was carried out, giving the extensive testing required on a 4-high Hille 100 rolling mill. Controls of rolling speed, reduction, strip width and friction at the roll/strip interface were conducted to analyse the rolling pressure, rolling torque and strip surface roughness. Results are obtained for the first pass and second pass rolling. Rolling speed does not have a conclusive effect on the rolling force, torque and strip surface roughness. Thickness reduction has a linear relationship with the rolling force and torque, and an increase of reduction corresponded with reduced surface roughness. Strip width increases the required rolling force and torque increases, but it does not show a significant influence on the strip surface roughness. Lubrication reduces the required rolling force and torque, and decreases the strip surface roughness. The research findings can provide a reference in practical rolling of ultra thin strip.

Ren, TR, Kwok, NM, Liu, DK, Huang, SD & IEEE 1970, 'Path Planning for a Robotic Arm Sand-blasting System', 2008 INTERNATIONAL CONFERENCE ON INFORMATION AND AUTOMATION, VOLS 1-4, IEEE International Conference on Information and Automation, IEEE, Zhangjiajie City, Hunan, China, pp. 1067-1072.
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Steel bridges are vulnerable to corrosion and their surfaces have to be de-rusted and repainted regularly. Since the process is complicated, expensive and the removed paints are harmful to human workers' health; the use of an automatic robotic system would be an attractive alternative. This paper presents an approach for planning paths for a robotic arm used in the sand-blasting operation. A hexagonal topologybased coverage pattern is adopted to reduce the amount of un-blasted areas and an editing process is included to confine the blasted areas within desirable boundaries. Furthermore, a genetic algorithm is employed to obtain an effective path with minimum arm travel distances and magnitude of turns. Collisions to obstacles are alleviated by making use of the force-field strategy. The effectiveness of the proposed methods is verified by simulations based on an industrial robot arm model and a complex bridge environment. © 2008 IEEE.

Rosseel, E, Vandervorst, W, Clarysse, T, Goossens, J, Moussa, A, Lin, R, Petersen, DH, Nielsen, PF, Hansen, O, Bennett, NS & Cowern, NEB 1970, 'Impact of multiple sub-melt laser scans on the activation and diffusion of shallow Boron junctions', 2008 16th IEEE International Conference on Advanced Thermal Processing of Semiconductors, 2008 16th International Conference on Advanced Thermal Processing of Semiconductors (RTP), IEEE, Las Vegas, NV, pp. 135-+.
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Sackermann, R & Deuse, J 1970, 'Determination of assembly times in low volume high mix production', 38th International Conference on Computers and Industrial Engineering 2008, pp. 1803-1809.
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Because of fast changing and chaotic markets manufacturer of customer individual products (low volume high mix production) are forced to design, plan and calculate products at frequent intervals. Therefore time studies have to generate precise results by less effort. For good results right from the start of the planning process, times have to be determined even in the early phases of the planning process. Time studies in these phases are usually based on diffuse and incomplete information. Today's methods are comparing and estimating by experts or extensive and complex statistic procedures. These methods are suboptimal, because they are either imprecise and strongly subjective or effortful and highly complex. In this paper a new method for the determination of times of manual assembly processes is introduced. The method is applicable from the early phases of the planning process and can be used up to the start of production. It is no longer necessary to use different methods in every planning phase, because the new method copes with the upcoming information as it becomes more detailed. To integrate diffuse information the new method's core is a knowledge-based system using fuzzy-logic. The rule-base of this system is set up once by an automatic algorithm and can be optimized by experts. With this new method it is possible to get adequate time data in the required precision in every phase of the planning process. Copyright© (2008) by Computers & Industrial Engineering.

Taha, T, Miro, JV, Dissanayake, G & IEEE 1970, 'POMDP-based long-term user intention prediction for wheelchair navigation', 2008 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, VOLS 1-9, IEEE International Conference on Robotics and Automation, IEEE, Pasadena, USA, pp. 3920-3925.
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This paper presents an intelligent decision-making agent to assist wheelchair users in their daily navigation activities. Several navigational techniques have been successfully developed in the past to assist with specific behaviours such as 'door passing' or 'corridor following'. These shared control strategies normally require the user to manually select the level of assistance required during use. Recent research has seen a move towards more intelligent systems that focus on forecasting users' intentions based on current and past actions. However, these predictions have been typically limited to locations immediately surrounding the wheelchair. The key contribution of the work presented here is the ability to predict the users' intended destination at a larger scale, that of a typical office arena. The systems relies on minimal user input - obtained from a standard wheelchair joystick - in conjunction with a learned Partially Observable Markov Decision Process (POMDP), to estimate and subsequently drive the user to his destination. The projection is constantly being updated, allowing for true user-platform integration. This shifts users' focus from fine motor-skilled control to coarse control broadly intended to convey intention. Successful simulation and experimental results on a real wheelchair robot demonstrate the validity of the approach. ©2008 IEEE.

Taha, T, Valls Miro, J & Dissanayake, G 1970, 'Intention driven assistive wheelchair navigation', Proc. of 'Robotic Helpers: User Interaction, Interfaces and Companions in Assistive and Therapy Robotics', a Workshop at ACM/IEEE Human Robot Interaction 2008 (HRI 2008), ACM/IEEE Human Robot Interaction, Technical Report 470, University of Hertfordshire, Amsterdam, the Netherlands, pp. 71-77.
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This paper presents an intelligent decision-making agent to assist wheelchair users in their daily navigation activities. The system has the ability to predict the users intended destination at a larger scale, that of a typical office or home arena. This system relies on minimal user input - obtained from a standard wheelchair joystick - in conjunction with a learned Partially Observable Markov Decision Process (POMDP), to estimate and subsequently aid in driving the user to the destination. The projection is constantly being updated, allowing for true user-platform integration. This shifts users focus from fine motor-skilled control to coarse guidance, broadly intended to convey intention. Successful simulation and experimental results on a real automated wheelchair platform demonstrate the validity of the approach.

Valls Miro, J & Dissanayake, G 1970, 'Robotic 3D Visual Mapping for Augmented Situational Awareness in Unstructured Environments', Proceedings of the EURON/IARP International Workshop on Robotics for Risky Interventions and Surveillance of the Environment (RISE 2008), EURON/IARP Robotics for Risky Interventions and Surveillance of the Environment, University of Jaume I, Technical Report Colleccio e-Treballs d'Informatica i Technologia" Num. 4", Benicassim, Spain.

Wang, Z, Dissanayake, G & IEEE 1970, 'Observability Analysis of SLAM Using Fisher Information Matrix', 2008 10TH INTERNATIONAL CONFERENCE ON CONTROL AUTOMATION ROBOTICS & VISION: ICARV 2008, VOLS 1-4, 10th International Conference on Control, Automation, Robotics and Vision, IEEE, Hanoi, VIETNAM, pp. 1242-1247.
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Wassermann, J & Parnell, J 1970, 'The art of noise communication', Annual Conference of the Australian Acoustical Society, AAS'08, pp. 215-221.
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Since Roman times, there have been continual attempts to mitigate the impacts of noise, and it is the assessment, understanding, communication and management of noise impacts that has provided the challenge for all involved in the process of reducing the impacts of noise. It is however, the communication of noise impacts to those who are, or potentially will be impacted that is often given the least consideration and is done in an ad hoc and inconsistent way. The following paper examines the key aspects of noise communication and attempts to provide a summary of current practice and suggest strategies for improving the communication of information on noise so that it achieves the best outcomes. There is an examination of the statement by Paul Schomer (2005) that while good public relations may result in a 5 dB bonus (US EPA, 1974) the converse is also true, with bad public relations equivalent to a 5 dB penalty. The authors also discuss the merit of adopting multiple assessment criteria and introduce the concept of a risk based approach to communicating the noise impact message.

Wei, DB & Jiang, ZY 1970, 'Modelling of nanocrack evolution in body-centred-cubic iron', Proceedings of the 6th International Conference on Engineering Computational Technology.
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Cracking is not a 'reversible' operation, but the very small crack may be healed if the maximum temperature of the heat-treatment is sufficient to bring the atoms on either side of the crack to within a mutual range by thermal agitation. In this paper, a molecular dynamics model was developed to investigate the nanocrack healing process in BCC Fe not only at elevated temperature but also under compressive stress. The nanocrack in BCC Fe crystal can be healed completely at 1173K in4.5ps or healed under compressive stress at loading rate ΔKI=0.025MPa m1/2/ps in 30ps. Dislocations and voids appear during healing and their positions change continuously. In the case of heating, the distribution of the defects in the cell is not homogenous. In the case of loading, most defects can be found in the area of the original crack. © 2008 Civil-Comp Press.

Wei, DB, Jiang, ZY, Lu, C, Tang, YD & Tieu, AK 1970, 'Effect of Surface Texture on Deformation Behavior of Asperity in Cold Metal Forming', Frontiers In Materials Science And Technology, International Conference on Frontiers in Materials Science and Technology, Trans Tech Publications Ltd., Brisbane, AUSTRALIA, pp. 185-188.
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It was impossible to obtain the transverse friction along the strip width in most previous studies of cold strip rolling because the surface roughness lays were assumed to be vertical to the rolling direction. In this study, several types of oblique roughness textures were manufactured on aluminum samples and compression tests were carried out to obtain the effect of different textures on the deformation behavior of surface asperity. Different surface textures resulted in very different peak value of stress. It was found that stress was high and changed dramatically at the initial compression stage but tended to be stable when the total reduction increased. The asperity of which the top angle is 160 degrees showed relatively high resistance to deformation.

Wei, DB, Jiang, ZY, Lu, C, Tang, YD & Tieu, AK 1970, 'Effect of Surface Texture on Deformation Behavior of Asperity in Cold Metal Forming', Advanced Materials Research, International Conference on Frontiers in Materials Science and Technology, Trans Tech Publications, Ltd., Queensland Univ Technol, Brisbane, AUSTRALIA, pp. 185-188.
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It was impossible to obtain the transverse friction along the strip width in mostprevious studies of cold strip rolling because the surface roughness lays were assumed to be verticalto the rolling direction. In this study, several types of oblique roughness textures were manufacturedon aluminum samples and compression tests were carried out to obtain the effect of differenttextures on the deformation behavior of surface asperity. Different surface textures resulted in verydifferent peak value of stress. It was found that stress was high and changed dramatically at theinitial compression stage but tended to be stable when the total reduction increased. The asperity ofwhich the top angle is 160° showed relatively high resistance to deformation.

Xie, HB, Jiang, ZY, Wei, DB, Liu, XH & Wang, GD 1970, 'A Knowledge-Based System for Temperature Prediction in Hot Strip Mills', Advanced Materials Research, Trans Tech Publications Ltd., pp. 153-156.
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Rolling temperature is an important factor affecting mechanical properties of hot rolled strip significantly. Traditional techniques cannot meet higher precision control imperatives. In the present work, a novel knowledge-based system has been developed for the temperature prediction in hot strip mills. Neural network has been used for this purpose, which is an intelligent technique that can solve nonlinear problem of temperature control by learning from the samples. Furthermore, an annealing robust learning algorithm was presented to adjust the hidden node parameters as well as the weights of the adaptive neural networks. Simulations in a multi-object mode have been carried out to verify the effectivity of new neural optimization system. Calculation results confirm the feasibility of this approach and show a good agreement with experimental values obtained from a steel plant.

Xie, HB, Jiang, ZY, Wei, DB, Liu, XH & Wang, GD 1970, 'A Knowledge-Based System for Temperature Prediction in Hot Strip Mills', Advanced Materials Research, International Conference on Frontiers in Materials Science and Technology, Trans Tech Publications, Ltd., Queensland Univ Technol, Brisbane, AUSTRALIA, pp. 153-156.
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Rolling temperature is an important factor affecting mechanical properties of hot rolledstrip significantly. Traditional techniques cannot meet higher precision control imperatives. In thepresent work, a novel knowledge-based system has been developed for the temperature predictionin hot strip mills. Neural network has been used for this purpose, which is an intelligent techniquethat can solve nonlinear problem of temperature control by learning from the samples. Furthermore,an annealing robust learning algorithm was presented to adjust the hidden node parameters as wellas the weights of the adaptive neural networks. Simulations in a multi-object mode have beencarried out to verify the effectivity of new neural optimization system. Calculation results confirmthe feasibility of this approach and show a good agreement with experimental values obtained froma steel plant.

Zhang, X, Jiang, Z, Xie, H, Wei, D, Liu, X & Wang, G 1970, 'Analysis of the effects of casting roll parameters on temperature field and thermal stress during twin roll thin strip casting', Steel Research International, 12th International Conference on Metal Forming, Verlag Stahleisen Mbh, Cracow, POLAND, pp. 772-779.
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During twin-roll thin strip casting, the casting roll is a key part of casting mills, which can make the strip casting be stable and obtain the casting strip with good quality. Due to the thermal and contact stresses of the casting roll caused by non-steady temperature field, it will result in the roll surface cracks and the decrease of the service life. In this paper, using a 3D thermal-force coupling finite element analysis, the thermal characteristic of casting roll has been simulated during the twin-roll thin strip casting, the effects of the thickness of roll sleeve, the number and positions of cooling water holes and the materials of roll sleeve on temperature field and thermal stress have been discussed. This work will provide theoretical basis for optimum design of the casting roll. © 2008 Verlag Stahleisen GmbH, Düsseldorf.

Zhang, Z, Kodagoda, S, Ruiz, D, Katupitiya, J & Dissanayake, G 1970, 'Classification of Bidens in Wheat Farms', 2008 15TH INTERNATIONAL CONFERENCE ON MECHATRONICS AND MACHINE VISION IN PRACTICE (M2VIP), 15th International Conference on Mechatronics and Machine Vision in Practice, IEEE, Auckland, NEW ZEALAND, pp. 494-+.

Zhang, Z, Kodagoda, S, Ruiz, D, Katupitiya, J & Dissanayake, G 1970, 'Classification of Bidens in Wheat Farms', 2008 15th International Conference on Mechatronics and Machine Vision in Practice, 2008 15th International Conference on Mechatronics and Machine Vision in Practice (M2VIP), IEEE, Auckland, NZ, pp. 505-510.
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Bidens pilosa L (commonly known as cobbler's peg) is an annual broad leaf weed widely distributed in tropical and subtropical regions of the world and is reported to be a weed of 31 crops including wheat. Automatic detection of Bidens in wheat farms is a nontrivial problem due to their similarity in color and presence of occlusions. This paper proposes a methodology which could be used to discriminate Bidens from wheat to be used in operations such as autonomous weed destruction. A spectrometer is used to analyze the optical properties of Bidens and wheat leaves while achieving high classification results. However, due to the practical constraints of using spectrometers, a color camera based technique is proposed. It is shown that the color based segmentation followed by shape based validation algorithm gives rise to high detection rates with lower false detections. We have experimentally evaluated the algorithm with Bidens detection rate of 80% and a 10% false alarm rate.

Zhou, W, Miro, JV & Dissanayake, G 1970, 'Information-Driven 6D SLAM Based on Ranging Vision', 2008 IEEE/RSJ INTERNATIONAL CONFERENCE ON ROBOTS AND INTELLIGENT SYSTEMS, VOLS 1-3, CONFERENCE PROCEEDINGS, IEEE/RSJ International Conference on Intelligent Robots and Systems, IEEE, Nice, France, pp. 2072-2077.
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This paper presents a novel solution for building three-dimensional dense maps in unknown and unstructured environment with reduced computational costs. This is achieved by giving the robot the 'intelligence' to select, out of the steadily collected data, the maximally informative observations to be used in the estimation of the robot location and its surroundings. We show that, although the actual evaluation of information gain for each frame introduces an additional computational cost, the overall efficiency is significantly increased by keeping the matrix compact. The noticeable advantage of this strategy is that the continuously gathered data is not heuristically segmented prior to be input to the filter. Quite the opposite, the scheme lends itself to be statistically optimal and is capable of handling large data sets collected at realistic sampling rates. The strategy is generic to any 3D feature-based simultaneous localization and mapping (SLAM) algorithm in the information form, but in the work presented here it is closely coupled to a proposed novel appearance-based sensory package. It consists of a conventional camera and a range imager, which provide range, bearing and elevation inputs to visual salient features as commonly used by three-dimensional point-based SLAM, but it is also particularly well adapted for lightweight mobile platforms such as those commonly employed for Urban Search and Rescue (USAR), chosen here to demonstrate the excellences of the proposed strategy. ©2008 IEEE.