Publications

Al-Ani, A & Deriche, M 2004, 'Multi-Channel Subspace Mapping Using an Information Maximization Criterion', Multidimensional Systems and Signal Processing, vol. 15, no. 2, pp. 117-145.
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A new hybrid information maximization (HIM) algorithm is derived. This algorithm is able to perform subspace mapping of multi-channel signals, where the input (feature) vector for each of the channels is linearly transformed to an output vector. The algorithm is based on maximizing the mutual information (MI) between input and output sets for each of the channels, and between output sets across channels. Such formulation leads to a substantial redundancy reduction in the output sets, and the extraction of higher order features that exhibit coherence across time and/or space. In this paper, we develop the proposed algorithm and show that it combines efficiently the strengths of two well-known subspace mapping techniques, namely the principal component analysis (PCA) and the canonical correlation analysis (CCA). Unlike CCA, which is limited to two channels, the HIM algorithm can easily be extended to multiple channels. A number of simulations and real experiments are conducted to compare the performance of HIM to that of PCA and CCA.

Buist, M, Bernard, S, Nguyen, TV, Moore, G & Anderson, J 2004, 'Association between clinically abnormal observations and subsequent in-hospital mortality: a prospective study', RESUSCITATION, vol. 62, no. 2, pp. 137-141.
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Chang, KP, Center, JR, Nguyen, TV & Eisman, JA 2004, 'Incidence of hip and other osteoporotic fractures in elderly men and women: Dubbo osteoporosis epidemiology study', JOURNAL OF BONE AND MINERAL RESEARCH, vol. 19, no. 4, pp. 532-536.
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Chung, K & Sanagavarapu, AM 2004, 'A Circularly Polarised Stacked Electromagnetically Coupled Patch Antenna', IEEE Transactions on Antennas and Propagation, vol. 52, no. 5, pp. 1365-1370.
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Fisher, J, Hu, XQ, Stewart, TD, Williams, S, Tipper, JL, Ingham, E, Stone, MH, Davies, C, Hatto, P, Bolton, J, Riley, M, Hardaker, C, Isaac, GH & Berry, G 2004, 'Wear of surface engineered metal-on-metal hip prostheses', JOURNAL OF MATERIALS SCIENCE-MATERIALS IN MEDICINE, vol. 15, no. 3, pp. 225-235.
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Hutvagner, GJ, Simard, MJ, Mello, C & Zamore, P 2004, 'Sequence-specific inhibition of small RNA function', Plos Biology, vol. 2, no. 4, pp. 465-475.
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Hundreds of microRNAs (miRNAs) and endogenous small interfering RNAs (siRNAs) have been identified from both plants and animals, yet little is known about their biochemical modes of action or biological functions. Here we report that 2'-O-methyl oligonuc

Khosroshahi, ME, Valanezhad, A & Tavakoli, J 2004, 'Evaluation of mid-IR laser radiation effect on 316L stainless steel corrosion resistance in physiological saline', Amirkabir (Journal of Science and Technology), vol. 15, no. 58 B, pp. 107-115.
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The effects of a short pulsed (∼ 400 ns) multiline hydrogen fluoride (HF) laser radiation operating on average at 2.8 μm has been studied on 316L stainless steel in terms of optical and physical parameters. At low fluences ≤ 8 Jcm -2 (phase I) no morphological changes occurred at the surface and melting began at ∼ 8.8 Jcm -2 (phase II) which continued up to about 30 Jcm -2. In this range the melting zone was effectively produced by high temperature surface centres growth which subsequently joined these centres together. Thermal ablation via surface vaporization began at ∼ 33 Jcm -2 (phase III). The results of SEM evaluation and corrosion resistance experiment which was carried out using EG&G device with cyclic potentiodynamic polarization method in a physiological (Hank's) solution indicated that pitting corrosion sensitivity was decreased ie. enhancement of corrosion resistance. Also, the XRD results showed a double increase of γ(111) at microstructure, thus in effect a superaustenite stainless steel was obtained at an optimized melting fluence.

Lam, H, Ling, SS, Leung, FH & Tam, P 2004, 'Function estimation using a neural-fuzzy network and an improved genetic algorithm', International Journal Of Approximate Reasoning, vol. 36, no. 3, pp. 243-260.
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This paper presents the estimation of the transmission gains for an AC power line data network in an intelligent home. The estimated gains ensure the transmission reliability and efficiency. A neural-fuzzy network with rule switches is proposed to perform the estimation. An improved genetic algorithm is proposed to tune the parameters and the rules of the proposed neural-fuzzy network. By turning on or off the rule switches, an optimal rule base can be obtained. An application example will be given.

Lee, DK, Lança, AJ, Cheng, R, Nguyen, T, Ji, XD, Gobeil, F, Chemtob, S, George, SR & O'Dowd, BF 2004, 'Agonist-independent Nuclear Localization of the Apelin, Angiotensin AT 1, and Bradykinin B2 Receptors', Journal of Biological Chemistry, vol. 279, no. 9, pp. 7901-7908.
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Signaling of the apelin, angiotensin, and bradykinin peptides is mediated by G protein-coupled receptors related through structure and similarities of physiological function. We report nuclear expression as a characteristic of these receptors, including a nuclear localization for the apelin receptor in brain and cerebellum-derived D283 Med cells and the AT1 and bradykinin B2 receptors in HEK-293T cells. Immunocytochemical analyses revealed the apelin receptor with localization in neuronal nuclei in cerebellum and hypothalamus, exhibiting expression in neuronal cytoplasm or in both nuclei and cytoplasm. Confocal microscopy of HEK-293T cells revealed the majority of transfected cells displayed constitutive nuclear localization of AT1 and B2 receptors, whereas apelin receptors did not show nuclear localization in these cells. The majority of apelin receptor-transfected cerebellum D283 Med cells showed receptor nuclear expression. Immunoblot analyses of subcellular-fractionated D283 Med cells demonstrated endogenous apelin receptor species in nuclear fractions. In addition, an identified nuclear localization signal motif in the third intracellular loop of the apelin receptor was disrupted by a substituted glutamine in place of lysine. This apelin receptor (K242Q) did not exhibit nuclear localization in D283 Med cells. These results demonstrate the following: (i) the apelin receptor exhibits nuclear localization in human brain; (ii) distinct cell-dependent mechanisms for the nuclear transport of apelin, AT 1, and B2 receptors; and (iii) the disruption of a nuclear localization signal sequence disrupts the nuclear translocation of the apelin receptor. This discovery of apelin, AT1, and B2 receptors with agonist-independent nuclear translocation suggests major unanticipated roles for these receptors in cell signaling and function.

Leung, FH, Lam, H, Ling, SS & Tam, P 2004, 'Optimal and stable fuzzy controllers for nonlinear systems based on an improved genetic algorithm', IEEE Transactions On Industrial Electronics, vol. 51, no. 1, pp. 172-182.
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This paper addresses the optimization and stabilization problems of nonlinear systems subject to parameter uncertainties. The methodology is based on a fuzzy logic approach and an improved genetic algorithm (GA). The TSK fuzzy plant model is employed to describe the dynamics of the uncertain nonlinear plant. A fuzzy controller is then obtained to close the feedback loop. The stability conditions are derived. The feedback gains of the fuzzy controller and the solution for meeting the stability conditions are determined using the improved GA. In order to obtain the optimal fuzzy controller, the membership functions are further tuned by minimizing a defined fitness function using the improved GA. An application example on stabilizing a two-link robot. arm will be given.

Leung, K, Leung, FH, Lam, H & Ling, SS 2004, 'On interpretation of graffiti digits and characters for eBooks: Neural-fuzzy network and genetic algorithm approach', IEEE Transactions On Industrial Electronics, vol. 51, no. 2, pp. 464-471.
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This paper presents the rule optimization, tuning of the membership functions, and optimization of the number of fuzzy rules, of a neural-fuzzy network (NFN) using a genetic algorithm (GA). The objectives are achieved, by training a proposed NFN with rule switches. The proposed NFN and GA are employed to interpret graffiti number inputs and commands for electronic books (eBooks).

Livshits, G, Deng, HW, Nguyen, TV, Yakovenko, K, Recker, RR & Eisman, JA 2004, 'Genetics of bone mineral density: Evidence for a major pleiotropic effect from an intercontinental study', JOURNAL OF BONE AND MINERAL RESEARCH, vol. 19, no. 6, pp. 914-923.
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Nguyen, ND, Ahlborg, HG & Nguyen, TV 2004, 'Does hip strength measures account for the difference in hip fracture incidence between the Chinese and Caucasian populations?', BONE, vol. 35, no. 4, pp. 998-999.
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Nguyen, TD, Nguyen, TA, Pham, MC, Piro, B, Normand, B & Takenouti, H 2004, 'Mechanism for protection of iron corrosion by an intrinsically electronic conducting polymer', JOURNAL OF ELECTROANALYTICAL CHEMISTRY, vol. 572, no. 2, pp. 225-234.
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Nguyen, TT, Taylor, PWJ, Redden, RJ & Ford, R 2004, 'Genetic diversity estimates in Cicer using AFLP analysis', PLANT BREEDING, vol. 123, no. 2, pp. 173-179.
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Nguyen, TV, Center, JR & Eisman, JA 2004, 'Bone mineral density-independent association of quantitative ultrasound measurements and fracture risk in women', OSTEOPOROSIS INTERNATIONAL, vol. 15, no. 12, pp. 942-947.
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Nguyen, TV, Center, JR & Eisman, JA 2004, 'Osteoporosis: Underrated, underdiagnosed and undertreated', Medical Journal of Australia, vol. 180, no. 5 SUPPL..
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Osteoporosis is: ■ Underrated Currently costs about $7 billion annually in Australia. Has high morbidity and 2-3-fold increase in risk of death after any major osteoporotic fracture. Genetic factors contribute highly to risk, modified by lifestyle and hormonal factors. ■ Underdiagnosed Bone density is a good predictor of subsequent risk. Anyone with a low-trauma fracture has osteoporosis unless proven otherwise. Every individual with a low trauma fracture should be investigated for exclusion of underlying osteoporosis and considered for effective treatment to reduce future fracture risk. More than 75% of women and about 90% of men with a high likelihood of osteoporosis are not investigated. ■ Undertreated More than 75% of those affected are not treated. Effective treatments (eg, hormone replacement therapy, selective oestrogen receptor modifiers and bisphosphonates) reduce fracture risk by 30%-60%. Simple measures like vitamin D and calcium supplementation and use of hip protectors can reduce hip fractures, particularly in institutionalised and housebound elderly people.

Nguyen, TV, Center, JR, Pocock, NA & Eisman, JA 2004, 'Limited utility of clinical indices for the prediction of symptomatic fracture risk in postmenopausal women', OSTEOPOROSIS INTERNATIONAL, vol. 15, no. 1, pp. 49-55.
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Pongchaiyakul, C, Nguyen, ND, Pongchaiyakul, C & Nguyen, TV 2004, 'Development and validation of a new clinical risk index for prediction of osteoporosis in Thai women', Journal of the Medical Association of Thailand, vol. 87, no. 8, pp. 910-916.
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The objective of this study was to develop and validate a new simple tool for identifying Thai women who are at high risk of having osteoporosis. A total of 322 women, aged > 45 years, were randomly divided into two cohorts: a development (n = 130) and a validation cohort (n = 192). Femoral neck and lumbar spine BMD were measured by LUNAR DPX-IQ densitometer. The prevalence of osteoporosis (defined by BMD T-scores ≤ -2.5) was 33 per cent by either femoral neck or lumbar spine BMD. Khon Kaen Osteoporosis Study (KKOS), scoring based on age and weight was calculated and applied to the development cohort. Individuals with KKOS score ≤ -1 were defined as "high risk"; otherwise a "low risk" was defined. In the validation cohort, the sensitivity and specificity of KKOS was 70 and 73 per cent, respectively. Furthermore, if the high risk individuals identified by KKOS are to be treated, and if the treatment reduces fracture incidence by 50 per cent and assuming that treatment cost is 10 bahts per day, then the cost to prevent one fracture is estimated to be 466, 695 bahts per year. These data suggest that although age and body weight can be used to identify Thai women who are at high risk of having osteoporosis, its application to the general population requires further research to arrive at the optimal cost-benefit for the community.

Pongchaiyakul, C, Nguyen, TV, Kosulwat, V, Rojroongwasinkul, N, Charoenkiatkul, S, Eisman, JA & Rajatanavin, R 2004, 'Effects of physical activity and dietary calcium intake on bone mineral density and osteoporosis risk in a rural Thai population', OSTEOPOROSIS INTERNATIONAL, vol. 15, no. 10, pp. 807-813.
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Su, SW, Bao, J & Lee, P 2004, 'Analysis of decentralized integral controllability for nonlinear systems', Computers and Chemical Engineering, vol. 28, no. 9, pp. 1781-1787.
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his paper extends the concept of decentralized integral controllability to nonlinear process, and presents a steady state sufficient condition by using the singular perturbation theory. A numerical method is provided to facilitate the analysis of the proposed condition and is illustrated using an example of a dual tank level control system.

Thakkinstian, A, D'Este, C, Eisman, J, Nguyen, T & Attia, J 2004, 'Meta-analysis of molecular association studies: Vitamin D receptor gene polymorphisms and BMD as a case study', JOURNAL OF BONE AND MINERAL RESEARCH, vol. 19, no. 3, pp. 419-428.
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Tran, NT, Raponi, M, Dawes, IW & Arndt, GM 2004, 'Control of specific gene expression in mammalian cells by co-expression of long complementary RNAs', FEBS Letters, vol. 573, pp. 127-134.
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Zochling, J, Nguyen, TV, March, LM & Sambrook, PN 2004, 'Quantitative ultrasound measurements of bone: measurement error, discordance, and their effects on longitudinal studies', OSTEOPOROSIS INTERNATIONAL, vol. 15, no. 8, pp. 619-624.
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Ahlborg, HG, Nguyen, N, Nguyen, TV, Center, JR & Eisman, JA 2004, 'Contribution of hip strength indices to hip fracture risk in elderly women and men', JOURNAL OF BONE AND MINERAL RESEARCH, 26th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research, AMER SOC BONE & MINERAL RES, Seattle, WA, pp. S430-S430.

Al-Ani, A & Bennamoun, M 2004, 'An edge fusion approach based on the concept of multiple detector behavior', Conference Proceedings - IEEE International Conference on Systems, Man and Cybernetics, pp. 2999-3003.
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One of the fundamental steps in image processing is edge detection. The performance of any edge detection method is highly affected by the choice of parameters, e.g. thresholds. For some applications, such as identi cat ion of objects in a scene, the interesting regions do not usually cover the whole image. Hence, applying edge detection with global parameters to these images will detect Edges of Interest (EoI) as well as edges caused by background details, illumination or re ect ance. We present here a new edge fusion approach that aims at identifying edges of interest and discarding unwanted edges. For this purpose, different parameter values are used to generate edge images from a given gray-scale image. The image is then divided into small windows and for each window the local detection accuracy of the various parameter values are estimated. Finally, the edge images are fused to produce a new edge image by locally choosing parameter values that achieve maximum detection accuracy. Initial results have shown that this method has the potential to produce very promising results. © 2004 IEEE.

Al-Jumaily, A & Kozak, S 2004, 'Behaviour Based Multi Robot Cooperation by Target/Task Negotiation', Proceedings of the 2004 IEEE Conference on Robotics, Automation and Mechatronics (RAM), IEEE Conference on Robotics, Automation and Mechatronics, IEEE, Singapore, pp. 661-666.
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A multi agent approach and robotics behaviors can be classified as a type of distributed intelligence. This distributed intelligence has an advantage to solving particular problems through benefiting from "divide and conquer" approach. Inherent parallelism of multiple agents can do many, perhaps different things, at the same time. Multiple agents are able to be in different places at the same time and can achieve different goals at the same time. Our paper is presenting achieving of static and dynamic goals completion through agent negotiation. The robotic agents shall assist each other in goal acquisition. This can be achieved in any environment with no map or determined damnation. The agents in our work do not necessarily know it's location in the environment during its goal acquisition. Our work is allowing easy location communication between agents in indoor environment.

Al-Jumaily, A & Leung, C 2004, 'A Hybrid System For Multi-agent Exploration', Proceedings of 2004 IEEE International Conference on Fuzzy Systems, 2004, Volume 1, IEEE International Conference on Fuzzy Systems, IEEE, Budapest, Hungary, pp. 209-213.
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This paper describes a multi-agent system that performs exploration and target seeking. A bidding scheme is applied to obtain assistance and cooperation between the mobile robots. An occupancy grid-based map and laser sensors are used for mapping. Frontier based exploration is implemented to determine unexplored areas to search. Targets are identified by designated colours in the vision sensors. Wave front propagation is used for path planning to both the frontiers and the targets. Fuzzy logic is applied to the laser readings to perform collision avoidance.

Al-Jumaily, A, Al-Hmouz, R & Gulrez, T 2004, 'Probabilistic Road Maps with Obstacle Avoidance in Cluttered Dynamic Environment', 2004 International Conference on Intelligent Sensors, Sensor Networks and Information Processing Proceedings, International Conference on Intelligent Sensors, Sensor Networks and Information Processing, IEEE, Melbourne, Australia, pp. 241-246.
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The paper presents an experimental study of a probabilistic road map (PRM) based obstacle avoiding algorithm, for motion planning of a non-holonomic mobile robot in a cluttered dynamic environment. The PRM approach uses a fast and simple local planner to build a network representation of the configuration space. It trades off the distance to both static objects and moving obstacles in computing the travelled path. Our work has been implemented and tested on Player/Stage, a real time robotic software, in extensive simulation runs. The different experiments demonstrate that our approach is well suited to control the motions of a robot in a cluttered environment and demonstrates its advantages over other techniques.

Baheiraei, A, Pocock, NA, Ritchie, JE, Eisman, JA & Nguyen, TV 2004, 'Smoking as a major osteoporosis risk factor among Iranian Australian women', JOURNAL OF BONE AND MINERAL RESEARCH, 26th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research, AMER SOC BONE & MINERAL RES, Seattle, WA, pp. S431-S431.

Center, JR, Nguyen, TV, Pocock, NA & Eisman, JA 2004, 'Volumetric bone density at the femoral neck as a common measure of hip fracture risk for men and women', JOURNAL OF CLINICAL ENDOCRINOLOGY & METABOLISM, ENDOCRINE SOC, pp. 2776-2782.
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Chung, K & Sanagavarapu, AM 2004, 'A High Performance Circularly Polarised Electromagnetically Coupled Patch Antenna with Low Mutual Coupling', Proceedings of Workshop on the Application of Radio Science, (WARS) 2004, The Workshop on the Application of Radio Science, Australian Government IPS Radio and Space Services, Hobart, Tasmania, Australia, pp. 1-4.

Chung, K & Sanagavarapu, AM 2004, 'Effect of Dielectric Material Tolerance On the Performance of Singly-fed Circularly Polarised Stacked Patch Antennas', Proceedings of 2004 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, The Institute of Electrical and Electronic Engineers, Inc (IEEE), Monterey, California, USA, pp. 479-482.

Chung, K & Sanagavarapu, AM 2004, 'Effect of Superstrate Thickness on the Performance of Broadband Circularly Polarised Stacked Patch Antenna', Proceedings of 2004 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, The Institute of Electrical and Electronics Engineers, Inc (IEEE), Monterey, California, USA, pp. 687-690.

Chung, K & Sanagavarapu, AM 2004, 'Experimental Study on the Performance of Circularly Polarised Stacked Patch Antenna Against Layer Displacements', Proceedings of The 2004 International Symposium on Antennas and Propagation (ISAP'04), International Symposium on Antennas and Propagation, The Institute of Electronics, Information and Communication Engineers, Sendai, Japan, pp. 397-400.

Fisher, J, McEwen, HMJ, Tipper, JL, Galvin, AL, Ingram, J, Kamali, A, Stone, MH & Ingham, E 1970, 'Wear, debris, and biologic activity of cross-linked polyethylene in the knee - Benefits and potential concerns', CLINICAL ORTHOPAEDICS AND RELATED RESEARCH, Joint Annual Meeting of the Knee-Society/Association-of-Hip-and-Knee-Surgeons, LIPPINCOTT WILLIAMS & WILKINS, New Orleans, LA, pp. 114-119.
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Fisher, J, Stewart, TD, Tipper, JL, Hatton, A & Ingham, E 2004, 'Wear, debris and functional biocompatability of third and fourth generation ceramic on ceramic bearing couples', Transactions - 7th World Biomaterials Congress, p. 223.
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Wear, debris, and functional biocompatibility of third generation Biolox Forte and fourth generation Biolox Delta ceramic bearing couples under standard and micro separation simulator testing were discussed. Microseparation sub-luxation testing was found to be necessary to reproduce clinically relevant stripe wear on both materials. Under standard simulator conditions, the wear of both materials was very low with the wear of Biolox Delta being lower than the wear of Biolox Forte. The low wear, even under the most severe loading conditions, combined with good biocompatibility of the wear debris, indicate that third and fourth generation ceramic on ceramic bearing couples are a good choice for active, high demand patients.

Galvin, AL, Endo, MM, Tipper, JL, Ingham, E & Fisher, J 2004, 'Functional biological activity of non-crosslinked and crosslinked UHMWPE hip joint prostheses', Transactions - 7th World Biomaterials Congress, p. 145.
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The wear rates, debris and biological activity of non-crosslinked and crosslinked ultra high molecular weight polyethylene (UHMWPE) hip joint prostheses were studied. The non-crosslinked, slightly crosslinked and highly crosslinked samples of UHMWPE were gamma irradiated in nitrogen and were measurements were taken using a coordinate measuring machine. SEM was used for the analysis of the wear debris from the materials. It was found that the wear rate of the highly crosslinked UHMWPE was lower than for the other materials. While the wear rate of the highly crosslinked materials was low, it only generated a two fold reduction in functional biological activity and osteolytic potential.

Galvin, AL, Tipper, JL, McEwen, HMJ, Williams, S, Stone, MH, Ingham, E & Fisher, J 2004, 'Nanometre sized polyethylene wear debris in hip and knee prostheses', Transactions - 7th World Biomaterials Congress, p. 345.
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The nanometer sized wear debris of ultra high molecular weight polyethylene (UHMWPE) 1020 GVF generated in hip and knee prostheses was studied using a high resolution field emission gun scanning electron microscopy (FEGSEM). The samples were foil packed and irradiated with 4MRad gamma irradiation in a vacuum. A coordinate measuring machine (CMM) was used to measure the wear of the samples. All tests were carried out in 25% bovine serum diluted with 0.1% sodium azide and were run to 5 million cycles. It was observed that the UHMWPE debris from the knee prostheses was generally larger than the debris from the hip prostheses.

Huang, T & Sanagavarapu, AM 2004, 'Microwave Imaging of Perfect Electrically Conducting Cylinder by Micro-Genetic Algorithm', Proceedings of 2004 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, IEEE AP-S International Symposium on Antennas and Propagation, IEEE, Monterey, USA, pp. 221-224.

Huang, T & Sanagavarapu, AM 2004, 'Microwave Imaging of Three-Dimensional Dielectric Objects', Proceedings of the 2004 International Symposium on Antennas and Propagation (ISAP'04), International Symposium on Antennas and Propagation, IEEE, Sendai, Japan, pp. 613-616.

Huang, T & Sanagavarapu, AM 2004, 'Microwave Imaging of Three-Dimensional Dielectric Objects Using Micro-Genetic Algorithm', Proceedings of the IASTED International Conference on Antennas, Radar and Wave Propagation (ARP 2004), IASTED International Conference on Antennas, Radar and Wave Propagation, IASTED, Banff, Canada, pp. 111-114.
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An electromagnetic (EM) inverse scattering problem that involves the reconstruction of microwave images for three-dimensional (3-D) objects is considered in this paper. This ill-posed and nonlinear problem is treated as a global optimization problem, and is solved by the application of micro-genetic algorithm (m-GA). The reconstructed results obtained by m-GA have shown that it is an effective technique for microwave image reconstruction.

Huang, T, Chiu, H & Sanagavarapu, AM 2004, 'Performance Optimization of Microwave Filters Using Photonic Band Gap (PBG) Structures', Proceedings of 2004 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, IEEE AP-S International Symposium on Antennas and Propagation, IEEE, Monterey, USA, pp. 3557-3560.

Ling, SH, Leung, FHF & Lam, HK 2004, 'Genetic Algorithm Based Variable-Structure Neural Network and its Industrial Application', IECON 2004: 30TH ANNUAL CONFERENCE OF IEEE INDUSTRIAL ELECTRONICS SOCIETY, VOL 2, 30th Annual Conference of the IEEE-Industrial-Electronics-Society (IECON), IEEE, Busan, SOUTH KOREA, pp. 1273-1278.

Meier, C, Nguyen, TV, Center, JR, Seibel, J & Eisman, JA 2004, 'Bone resorption and osteoporotic fractures in elderly men: The Dubbo Osteoporosis Epidemiology Study.', JOURNAL OF BONE AND MINERAL RESEARCH, 26th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research, AMER SOC BONE & MINERAL RES, Seattle, WA, pp. S88-S88.

Meier, C, Nguyen, TV, Center, JR, Seibel, MJ & Eisman, JA 2004, 'BONE RESORPTION RATE IS AN INDEPENDENT PREDICTOR OF OSTEOPOROTIC FRACTURES IN ELDERLY MEN. THE DUBBO STUDY', CALCIFIED TISSUE INTERNATIONAL, SPRINGER, pp. S65-S65.

Nelson, AE, Seibel, MJ, Howe, CJ, Nguyen, TV, de Winter, J, Leung, K, Trout, CJ, Baxter, RC, Handelsman, DJ, Irie, M, Kazlauskas, R & Ho, KK 2004, 'Variation of bone and connective tissue turnover markers with age, gender, BMI and ethnicity in elite athletes.', JOURNAL OF BONE AND MINERAL RESEARCH, 26th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research, AMER SOC BONE & MINERAL RES, Seattle, WA, pp. S374-S374.

Nguyen, ND, Eisman, JA & Nguyen, TV 2004, 'Effects of bisphosphonates on hip fracture risk reduction: A bayesian analysis of clinical trials.', JOURNAL OF BONE AND MINERAL RESEARCH, 26th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research, AMER SOC BONE & MINERAL RES, Seattle, WA, pp. S94-S94.

Nguyen, ND, Pongchaiyakul, C, Center, JR, Eisman, JA & Nguyen, TV 2004, 'Prediction of hip fracture in the elderly by fall-related factors', JOURNAL OF BONE AND MINERAL RESEARCH, 26th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research, AMER SOC BONE & MINERAL RES, Seattle, WA, pp. S48-S48.

Nguyen, TV, Center, JR & Eisman, JA 2002, 'Osteoporosis: underrated, underdiagnosed and undertreated', MEDICAL JOURNAL OF AUSTRALIA, Conference on Bone and Joint Decade Approach, AUSTRALASIAN MED PUBL CO LTD, Canberra, AUSTRALIA, pp. S18-S22.

Nguyen, TV, Nguyen, NQ, Center, JR & Eisman, JA 2004, 'Long-term bone loss in men and women: Effects of quadriceps strength and body weight.', JOURNAL OF BONE AND MINERAL RESEARCH, 26th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research, AMER SOC BONE & MINERAL RES, Seattle, WA, pp. S233-S233.

Pham, TD, Crane, DI, Tannock, D & Beck, D 2004, 'Kullback-leibler dissimilarity of markov models for phylogenetic tree reconstruction', 2004 International Symposium on Intelligent Multimedia, Video and Speech Processing, ISIMP 2004, pp. 157-160.
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In this paper, we introduce the Kullback-Leibler dissimilarity measure of Markov-chain models for unaligned DNA sequences with application to the phylogenetic tree reconstruction of complete mammalian mitochondrial genomes. The tree obtained by our approach is generally in agreement with those obtained from other methods. Our proposed method is computationally efficient and very easy for computer implementation.

Pongchaiyakul, C, Nguyen, ND, Center, JR, Eisman, JA & Nguyen, TV 2004, 'Asymptomatic vertebral deformity as major risk factor for subsequent fractures and mortality: A 14-year prospective study.', JOURNAL OF BONE AND MINERAL RESEARCH, 26th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research, AMER SOC BONE & MINERAL RES, Seattle, WA, pp. S30-S30.

Pongchaiyakul, C, Nguyen, TV, Eisman, JA & Rajatanavin, R 2004, 'Contribution of lean tissue mass to the urban-rural difference in bone mineral density.', JOURNAL OF BONE AND MINERAL RESEARCH, 26th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research, AMER SOC BONE & MINERAL RES, Seattle, WA, pp. S230-S230.

Su, SW, Bao, J & Lee, P 2004, 'Decentralized control for processes with input and output nonlinearities', Proceedings of Chemeca 2004 Conference: 32nd Australasian Chemical Engineering Conference, Chemeca: Australasian Conference on Chemical Engineering, Chemeca 2004 Conference, Sydney, Australia, pp. 1-6.
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Decentralized control is the most widely used control strategy in the process industry because of its simplicity in controller design and implementation and its potential to achieve failure tolerant control. Actuator/sensor nonlinearities are often encountered in many chemical processes. This paper presents a new decentralized control method for processes which have static actuator/sensor nonlinearities, such as saturation, hysteresis and dead zone. The proposed decentralized integral controller is designed based on feedforward passivation, which can be applied to nonminimum phase processes and/or processes of high relative degree. The concept of marginally stable positive real systems is used to analyse the stability of a closed-loop system. The feedforward system is constructed to attain dynamic performance on the basis of frequency based passivity analysis. The proposed approach is used in the control of a quadruple tank process which has static nonlinearity in its actuators.

Su, SW, Bao, J & Lee, P 2004, 'Passivity based Internal Model Control', Proceedings of the 5th Asian Control Conference, Asian Control Conference, IEEE, Piscataway, USA, pp. 135-140.
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This paper proposes a new control method for multivariable nonlinear processes based on the internal model control (IMC) framework and the passivity theorem. The conventional IMC method involves inversion of the process, which is often difficult or even impossible. In the proposed method, the process is approximated using a passive system. The controller is designed to effectively invert the passive approximation. The stability of the closed-loop system is guaranteed by the passivity condition. The effectiveness of the proposed method is illustrated by using a mixing tank control problem.

Su, SW, Bao, J & Lee, PL 2004, 'Passivity based IMC control for multivariable nonlinear systems', 2004 5th Asian Control Conference, pp. 135-140.
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This paper proposes a new control method for multivariable nonlinear processes based on the Internal Model Control (IMC) framework and the Passivity Theorem. The conventional IMC method involves inversion of the process, which is often difficult or even impossible. In the proposed method, the process is approximated using a passive system. The controller is designed to effectively invert the passive approximation. The stability of the closed-loop system is guaranteed by the passivity condition. The effectiveness of the proposed method is illustrated by using a mixing tank control problem.

Tang, Z & Sanagavarapu, AM 2004, 'Effects of Signals Clustering on the Capacity of Indoor MIMO channels', Proceedings of The 2004 International Symposium on Antennas and Propagation (ISAP'04), International Symposium on Antennas and Propagation (ISAP'04), The Institute of Electronic, Information and Communication Engineers (IEICE), Sendai City, Japan, pp. 321-324.

Tang, Z & Sanagavarapu, AM 2005, 'Indoor Directional Channel Modelling for Future Wireless Communications', Proceedings of 2004 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, IEEE International Symposium on Antennas and Propagation, IEEE, Monterey, USA, pp. 3657-3660.
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The space-time multiple-input multiple-output (MIMO) technique is being developed as the potential solution for future high data rate wireless mobile communications. Channel modeling is very important for the design and analysis of the MIMO space-time systems it. The paper develops a stochastic double directional indoor MIMO channel model, and validates it with measurement data. The model addresses the issue of signal clustering encountered in an indoor channel. Directions of departure and of arrival of signal clusters are both considered. The model is verified by comparison with published measurement data. The model describes an indoor MIMO channel directly using a reference SISO cluster channel model. The model also provides a simple yet tractable framework for further investigation on MIMO techniques in a clustering indoor environment (10 refs.)

Tang, Z & Sanagavarapu, AM 2004, 'Performance of Beamforming and MIMO Technique in an Indoor Ricean Clustering Channel', Proceedings of the IASTED International Conference on Antennas, Radar and Wave Propagation (ARP 2004), The UASTED International Conference: Antennas, Radar, and Wave Propagation, ACTA Press, Banff, Canada, pp. 218-221.
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In this paper, we present a hybrid indoor MIMO channel model for predicting the performance of multiple-element antenna system. The model incorporates the wave clustering phenomena and combines the statistical characteristics of clusters with deterministic ray tracing method. The capacity of the MIMO channel is expressed as a function of spatial correlation at both the transmitter and the receiver. The results obtained by using the channel model are compared with measurement results available in the literature. Simulation results verify that the MIMO technique effectively exploits multipath fading. The paper also presents a comparison between MIMO and beamforming techniques in indoor environments.