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Full-Text Articles in Social and Behavioral Sciences

Kk-Theory And Spectral Flow In Von Neumann Algebras, J Kaad, R Nest, Adam C. Rennie Jan 2007

Kk-Theory And Spectral Flow In Von Neumann Algebras, J Kaad, R Nest, Adam C. Rennie

Faculty of Engineering and Information Sciences - Papers: Part A

We present a definition of spectral flow for any norm closed ideal J in any von Neumann algebra N. Given a path of selfadjoint operators in N which are invertible in N/J, the spectral flow produces a class in Ko(J).Given a semifinite spectral triple (A, H, D) relative to (N, t) with A separable, we construct a class [D] ? KK1(A, K(N)). For a unitary u ? A, the von Neumann spectral flow between D and u*Du is equal to the Kasparov product [u]A[D], and is simply related to the numerical spectral flow, and a refined C*-spectral flow.


Assessment Of Drucker-Prager Type Plasticity Models For Predicting The Behaviour Of Frp-Confined Concrete, T Yu, J G. Teng, Y L. Wong, S L. Dong Jan 2007

Assessment Of Drucker-Prager Type Plasticity Models For Predicting The Behaviour Of Frp-Confined Concrete, T Yu, J G. Teng, Y L. Wong, S L. Dong

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents a critical assessment of the ability of existing Drucker-Prager (D-P) type plasticity models to predict the behaviour of confined concrete using both experimental observations and a recent analytical model. This assessment shows that for a D-P plasticity model to succeed in predicting the behaviour of FRP-confined and other passively-confined concrete, it needs to possess the following three features: (a) a yield criterion which includes the third deviatoric stress invariant, (b) a hardening/softening rule which is dependent on the confining pressure; and (c) a flow rule which is dependent on both the confining pressure and the rate of …


The Dixmier Trace And Asymptotics Of Zeta Functions, Alan L. Carey, Adam C. Rennie, Aleksandr Sedaev, Fyodor A. Sukochev Jan 2007

The Dixmier Trace And Asymptotics Of Zeta Functions, Alan L. Carey, Adam C. Rennie, Aleksandr Sedaev, Fyodor A. Sukochev

Faculty of Engineering and Information Sciences - Papers: Part A

We obtain general theorems which enable the calculation of the Dixmier trace in terms of the asymptotics of the zeta function and of the trace of the heat semigroup. We prove our results in a general semi-finite von Neumann algebra. We find for p > 1 that the asymptotics of the zeta function determines an ideal strictly larger than Lp,∞ on which the Dixmier trace may be defined. We also establish stronger versions of other results on Dixmier traces and zeta functions.


Discovering Prediction Model For Environmental Distribution Maps, Ke Zhang, Huidong Jin, Nianjun Liu, Rob Lesslie, Lei Wang, Zhouyu Fu, Terry Caelli Jan 2007

Discovering Prediction Model For Environmental Distribution Maps, Ke Zhang, Huidong Jin, Nianjun Liu, Rob Lesslie, Lei Wang, Zhouyu Fu, Terry Caelli

Faculty of Engineering and Information Sciences - Papers: Part A

Currently environmental distribution maps, such as for soil fertility, rainfall and foliage, are widely used in the natural resource management and policy making. One typical example is to predict the grazing capacity in particular geographical regions. This paper uses a discovering approach to choose a prediction model for real-world environmental data. The approach consists of two steps: (1) model selection which determines the type of prediction model, such as linear or non-linear; (2) model optimisation which aims at using less environmental data for prediction but without any loss on accuracy. The latter step is achieved by automatically selecting non-redundant features …


Feature Subset Selection For Multi-Class Svm Based Image Classification, Lei Wang Jan 2007

Feature Subset Selection For Multi-Class Svm Based Image Classification, Lei Wang

Faculty of Engineering and Information Sciences - Papers: Part A

Multi-class image classification can benefit much from feature subset selection. This paper extends an error bound of binary SVMs to a feature subset selection criterion for the multi-class SVMs. By minimizing this criterion, the scale factors assigned to each feature in a kernel function are optimized to identify the important features. This minimization problem can be efficiently solved by gradient-based search techniques, even if hundreds of features are involved. Also, considering that image classification is often a small sample problem, the regularization issue is investigated for this criterion, showing its robustness in this situation. Experimental study on multiple benchmark image …


Synchrotron Radiation Computed Tomography Station At The Esrf Biomedical Beamline, C Nemoz, S Bayat, G Berruyer, T Brochard, P Coan, G Le Duc, J Keyrilainen, S Monfraix, M Renier, H Requardt, A Bravin, P Tafforeau, J F. Adam, M C. Biston, C Boudou, A M. Charvet, S Corde, H Elleaume, F Esteve, A Joubert, J Rousseau, I Tropres, M Fernandez, L Porra, P Suortti, S Fiedler, W Thomlinson Jan 2007

Synchrotron Radiation Computed Tomography Station At The Esrf Biomedical Beamline, C Nemoz, S Bayat, G Berruyer, T Brochard, P Coan, G Le Duc, J Keyrilainen, S Monfraix, M Renier, H Requardt, A Bravin, P Tafforeau, J F. Adam, M C. Biston, C Boudou, A M. Charvet, S Corde, H Elleaume, F Esteve, A Joubert, J Rousseau, I Tropres, M Fernandez, L Porra, P Suortti, S Fiedler, W Thomlinson

Faculty of Engineering and Information Sciences - Papers: Part A

The different tomography imaging modalities of the ESRF Medical Beamline are described and research applications are presented


Malicious Kgc Attacks In Certificateless Cryptography, Man Ho Au, Jing Chen, Joseph K. Liu, Yi Mu, Duncan S. Wong, Guomin Yang Jan 2007

Malicious Kgc Attacks In Certificateless Cryptography, Man Ho Au, Jing Chen, Joseph K. Liu, Yi Mu, Duncan S. Wong, Guomin Yang

Faculty of Engineering and Information Sciences - Papers: Part A

Identity-based cryptosystems have an inherent key escrow issue, that is, the Key Generation Center (KGC) always knows user secret key. If the KGC is malicious, it can always impersonate the user. Certificateless cryptography, introduced by Al-Riyami and Paterson in 2003, is intended to solve this problem. However, in all the previously proposed certificateless schemes, it is always assumed that the malicious KGC starts launching attacks (so-called Type II attacks) only after it has generated a master public/secret key pair honestly. In this paper, we propose new security models that remove this assumption for both certificateless signature and encryption schemes. Under …


Evolution Analysis Of Iterative Lmmse-App Detection For Coded Linear System With Cyclic Prefixes, Xiaojun Yuan, Qinghua Guo, Li Ping Jan 2007

Evolution Analysis Of Iterative Lmmse-App Detection For Coded Linear System With Cyclic Prefixes, Xiaojun Yuan, Qinghua Guo, Li Ping

Faculty of Engineering and Information Sciences - Papers: Part A

This paper is concerned with the iterative detection principles for coded linear systems with cyclic prefixes. We derive a matrix-form low-cost fast Fourier transform (FFT) based iterative LMMSE-APP detector and propose an evolution technique for the performance evaluation of the proposed detector. Numerical results show a good match between simulation and evolution prediction. ©2007 IEEE.


The Ofdm-Idma Approach To Wireless Communication Systems, Li Ping, Qinghua Guo, Jun Tong Jan 2007

The Ofdm-Idma Approach To Wireless Communication Systems, Li Ping, Qinghua Guo, Jun Tong

Faculty of Engineering and Information Sciences - Papers: Part A

This article outlines the basic principles of OFDM-IDMA. Comparisons with other alternative technologies such as OFDM-CDMA and OFDMA are provided. Some attractive features of OFMD-IDMA are explained, including low-cost iterative multi-user detection, flexible rate adaptation, frequency diversity, and significant advantages regarding spectral and power efficiency. © 2007 IEEE.


Performance Comparison Of Subtractive Resistive Readout With Conventional Resistive Readout For A High-Resolution Compact Gamma Camera, Y J. Qi, M J. Zhang, C L. Zhao, R F. Wojcik Jan 2007

Performance Comparison Of Subtractive Resistive Readout With Conventional Resistive Readout For A High-Resolution Compact Gamma Camera, Y J. Qi, M J. Zhang, C L. Zhao, R F. Wojcik

Faculty of Engineering and Information Sciences - Papers: Part A

The purpose of this study was to investigate an optimal readout for a high-resolution compact gamma camera with maximum performance in crystal element identifications. The compact camera is based on a pixellated Nal(Tl) crystal with 1.2 mm pixel size coupled to a 5" Hamamatsu R3292 PSPMT. A conventional resistive-chain readout was initially developed for the camera. Then a novel subtractive resistive readout developed was utilized to optimize the performance of the camera. The performance of the camera was evaluated by raw flood images of a 137Cs source. The results show that the conventional resistive readout results in a significant shrinkage …


Fast Encodable And Decodable Irregular Repeat Accumulate Codes From Circulant Permutation Matrices, S Tong, S Zhang, B Bai, X Wang Jan 2007

Fast Encodable And Decodable Irregular Repeat Accumulate Codes From Circulant Permutation Matrices, S Tong, S Zhang, B Bai, X Wang

Faculty of Engineering and Information Sciences - Papers: Part A

An approach to construct irregular repeat accumulate (RA) codes from circulant permutation matrices is presented. The constructed irregular RA codes can be encoded with shift registers and decoded in the turbo decoding fashion, which leads to a much faster convergence rate compared to the conventional full parallel decoding fashion.


Searchsleuth: The Conceptual Neighbourhood Of An Web Query, Jon Ducrou, Peter Eklund Jan 2007

Searchsleuth: The Conceptual Neighbourhood Of An Web Query, Jon Ducrou, Peter Eklund

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents SearchSleuth, a program developed to experiment with a form of automatic local analysis that extends the standard Web search interface to include a conceptual neighbourhood focused on a formal concept derived from the query. The conceptual neighbourhood is displayed with upper neighbours representative of a generalisation operation, and lower neighbours representative of a specialisation operation. SearchSleuth also introduces a notion of a categorisation operation, where the conceptual focus can shift to a sibling concept of the search concept.


A Study Of Hippocampal Shape Difference Between Genders By Efficient Hypothesis Test And Discriminative Deformation, Luping Zhou, Richard Hartley, Paulette Lieby, Nick Barnes, Kaarin Anstey, Nicolas Cherbuin, Perminder Sachdev Jan 2007

A Study Of Hippocampal Shape Difference Between Genders By Efficient Hypothesis Test And Discriminative Deformation, Luping Zhou, Richard Hartley, Paulette Lieby, Nick Barnes, Kaarin Anstey, Nicolas Cherbuin, Perminder Sachdev

Faculty of Engineering and Information Sciences - Papers: Part A

Hypothesis testing is an important way to detect the statistical difference between two populations. In this paper, we use the Fisher permutation and bootstrap tests to differentiate hippocampal shape between genders. These methods are preferred to traditional hypothesis tests which impose assumptions on the distribution of the samples. An efficient algorithm is adopted to rapidly perform the exact tests. We extend this algorithm to multivariate data by projecting the original data onto an "informative direction" to generate a scalar test statistic. This "informative direction" is found to preserve the original discriminative information. This direction is further used in this paper …


Remarks On Accessible Steady States For Some Coagulation-Fragmentation Systems, Miguel A. Herrero, Marianito R. Rodrigo Jan 2007

Remarks On Accessible Steady States For Some Coagulation-Fragmentation Systems, Miguel A. Herrero, Marianito R. Rodrigo

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper we consider some systems of ordinary differential equations which are related to coagulation-fragmentation processes. In particular, we obtain explicit solutions of such systems which involve certain coefficients obtained by solving a suitable algebraic recurrence relation. The coefficients are derived in two relevant cases: the high-functionality limit and the Flory-Stockmayer model. The solutions thus obtained are polydisperse (that is, is different from zero for all ) and may exhibit monotonically increasing or decreasing total mass. We also solve a monodisperse case (where is different from zero but is equal to zero for all ) in the high-functionality limit. …


Sobre La Infinidad De Los Numeros Primos: Un Enfoque Topologico, Marianito Rocha Rodrigo Jan 2007

Sobre La Infinidad De Los Numeros Primos: Un Enfoque Topologico, Marianito Rocha Rodrigo

Faculty of Engineering and Information Sciences - Papers: Part A

Un resultado bien conocido en la teor´ıa elemental de n´umeros, usualmente atribuido a Euclides, dice que hay un n´umero infinito de primos. Existen varias demostraciones de este resultado [1, 3] pero en esta nota mostraremos en detalle el enfoque ingenioso de Furstenberg [2], que utiliza conocimientos b´asicos de topolog´ıa, por ejemplo, espacios topol´ogicos, conjuntos abiertos y conjuntos cerrados.


Recovery Of Time-Dependent Parameters Of A Black-Scholes-Type Equation: An Inverse Stieltjes Moment Approach, Marianito R. Rodrigo, Rogemar S. Mamon Jan 2007

Recovery Of Time-Dependent Parameters Of A Black-Scholes-Type Equation: An Inverse Stieltjes Moment Approach, Marianito R. Rodrigo, Rogemar S. Mamon

Faculty of Engineering and Information Sciences - Papers: Part A

We show that the problem of recovering the time-dependent parameters of an equation of Black-Scholes type can be formulated as an inverse Stieltjes moment problem. An application to the problem of implied volatility calculation in the case when the model parameters are time varying is provided and results of numerical simulations are presented.


Multilevel Modelling Of The Incidence Of Visceral Leishmaniasis In Teresina, Brazil, G Werneck, C Costa, Alexander Walker, John David, M. P. Wand, J Maguire Jan 2007

Multilevel Modelling Of The Incidence Of Visceral Leishmaniasis In Teresina, Brazil, G Werneck, C Costa, Alexander Walker, John David, M. P. Wand, J Maguire

Faculty of Engineering and Information Sciences - Papers: Part A

Epidemics of visceral leishmaniasis (VL) in major Brazilian cities are new phenomena since 1980. As determinants of transmission in urban settings probably operate at different geographic scales, and information is not available for each scale, a multilevel approach was used to examine the effect of canine infection and environmental and socio-economic factors on the spatial variability of incidence rates of VL in the city of Teresina. Details on an outbreak of greater than 1200 cases of VL in Teresina during 1993-1996 were available at two hierarchical levels: census tracts (socio-economic characteristics, incidence rates of human VL) and districts, which encompass …


Editorial: Special Issue Contributed From Chemeca 2006-Australasian Process Modelling And Control Selected Papers, Mark Nelson, Brent Young Jan 2007

Editorial: Special Issue Contributed From Chemeca 2006-Australasian Process Modelling And Control Selected Papers, Mark Nelson, Brent Young

Faculty of Engineering and Information Sciences - Papers: Part A

The papers in this issue of Chemical Product and Process Modelling are substantially those that arose from special sessions on ``process simulation and control" (organised by Brent R. Young) and ``mathematical modeling" (organised by Mark I. Nelson) at the 34th Australasian Chemical Engineering Conference (held between 17-20th September 2006, in Auckland, New Zealand). The papers in this special issue are available at: http://www.bepress.com/cppm/vol2/iss2. The papers featured in this issue have been revised and extended from CHEMECA and re-reviewed before publication here.All the papers in this issue use mathematics. However, this special issue only features a small number of the presentations …


Watermarking Protocol Of Secure Verification, Jun Zhang, Weidong Kou, Kai Fan, Lei Ye Jan 2007

Watermarking Protocol Of Secure Verification, Jun Zhang, Weidong Kou, Kai Fan, Lei Ye

Faculty of Engineering and Information Sciences - Papers: Part A

The secure verification is important for watermarking protocols. A malicious arbitrator is able to remove an original watermark from an unauthorized copy of the digital content as a result of a security breach in the phase of arbitration and resell multiple copies of it with impunity. We propose a novel buyer-seller watermarking protocol of secure verification. In this scheme, a seller permutes an original watermark provided by a trusted Watermarking Certification Authority (WCA) and embeds it into digital content in an encrypted domain. In case an unauthorized copy is found, the seller can recover the original watermark from the watermark …


Turbulent Transfer Mechanism In Sediment-Laden Flow, Shu-Qing Yang Jan 2007

Turbulent Transfer Mechanism In Sediment-Laden Flow, Shu-Qing Yang

Faculty of Engineering and Information Sciences - Papers: Part A

Characteristics of turbulent flows in rivers can be significantly modified because of the presence of sediment particles and secondary currents/nonuniformity. This paper investigates why the measured vertical distributions of velocity deviate from the log law. In contrast to previous research that attributed the deviation to Richardson number only, this study demonstrates that like Reynolds shear stress (−equation image), momentum flux (uv) caused by the nonzero wall-normal velocity v is also responsible for these deviations. Starting from Reynolds equations, this paper shows that the classical log law can be obtained only when v = 0; otherwise the velocity v results in …


Discussion, Raymond Chambers Jan 2007

Discussion, Raymond Chambers

Faculty of Engineering and Information Sciences - Papers: Part A

Discussion on Bjornstad, J.F. 2007, "Non-Bayesian Multiple Imputation", Journal of Official Statistics, vol. 23, no. 4, pp. 433.


An Inside Look At Rfid Technology, Linda Castro, Samuel Fosso Wamba Jan 2007

An Inside Look At Rfid Technology, Linda Castro, Samuel Fosso Wamba

Faculty of Engineering and Information Sciences - Papers: Part A

RFID (Radio Frequency Identification) is considered one of the "hottest" technologies due to its particular capabilities to track and trace in real-time objects across the extended supply chain. This article gives an inside look at the RFID world in order to improve the level of understanding of this technology and the EPC Network. An introduction to RFID's systems, RFID's potential to improve the efficiency of operations, different areas of application, as well as a roadmap approach to undertake an RFID implementation will be discussed in this article.


Orientation Effect On Mechanical Properties Of Commercially Pure Titanium At Room Temperature, M Battaini, E V. Pereloma, Christopher Davies Jan 2007

Orientation Effect On Mechanical Properties Of Commercially Pure Titanium At Room Temperature, M Battaini, E V. Pereloma, Christopher Davies

Faculty of Engineering and Information Sciences - Papers: Part A

The effect of sample orientation on the mechanical properties of commercially pure (CP) titanium plate with a transverse split basal texture was investigated at room temperature (RT) using plane strain compression (PSC). A large variation in flow stress of up to (EBSD) and calculating Schmid factors for all important slip and twinning modes. Importantly, the Schmid factors were calculated for all orientations in Euler space because there are significant variations over all orientations for the PSC stress state, unlike uniaxial compression or tension. The Schmid factor analysis and twin data for the wide variety of orientations tested enabled the conclusion …


Integrating Rfid Technology And Epc Network Into A B2b Retail Supply Chain: A Step Toward Intelligent Business Processes, Samuel Fosso Wamba, Louis A. Lefebvre, Elisabeth Lefebvre Jan 2007

Integrating Rfid Technology And Epc Network Into A B2b Retail Supply Chain: A Step Toward Intelligent Business Processes, Samuel Fosso Wamba, Louis A. Lefebvre, Elisabeth Lefebvre

Faculty of Engineering and Information Sciences - Papers: Part A

This article introduces RFID technology and the EPC Network and investigates their potential for B-to-B eCommerce supply chain management. Based on empirical data gathered from four tightly interrelated firms from three layers of a supply chain, several scenarios integrating RFID and the EPC Network have been tested and evaluated. In the context of warehousing activities in one specific retail supply chain, the results indicate that i) the business process approach seems quite appropriate to capture the real potential of RFID and the EPC Network; ii) RFID technology and the EPC Network can improve the "shipping" and the "receiving" processes; iii) …


A Polyhedral Model For Carbon Nanotubes, Barry Cox, James Hill Jan 2007

A Polyhedral Model For Carbon Nanotubes, Barry Cox, James Hill

Faculty of Engineering and Information Sciences - Papers: Part A

A new structural model accounts for the curvature inherent in their cylindrical shape.


Properties Preserved Under Morita Equivalence Of C*-Algebras, Astrid An Huef, Iain Raeburn, Dana Williams Jan 2007

Properties Preserved Under Morita Equivalence Of C*-Algebras, Astrid An Huef, Iain Raeburn, Dana Williams

Faculty of Engineering and Information Sciences - Papers: Part A

We show that important structural properties of C*-algebras and the muliplicity numbers of representations are preserved under Morita equivalence.


Polymer Entanglement Density And Its Influence On Interfacial Friction, Philip G. Whitten, Hugh R. Brown Jan 2007

Polymer Entanglement Density And Its Influence On Interfacial Friction, Philip G. Whitten, Hugh R. Brown

Faculty of Engineering and Information Sciences - Papers: Part A

The entanglement density of amorphous glassy polymers is well known to control their fracture mechanisms under tensile loading. There have been some reports indicating substantial deformation of a glassy polymer’s surface region when exposed to interfacial friction. It is shown conclusively here that there is a direct correlation between the entanglement density of a glassy polymer and the deformation mechanisms that facilitate sliding friction. This correlation was shown experimentally by studying the topography of polymer surfaces following a single sliding pass by an inorganic glass sphere. Four different polymers were studied, including polystyrene cross linked to different degrees. It is …


Parameter Estimation Method Using An Extended Kalman Filter, Emmanuel D. Blanchard, Adrian Sandu, Corina Sandu Jan 2007

Parameter Estimation Method Using An Extended Kalman Filter, Emmanuel D. Blanchard, Adrian Sandu, Corina Sandu

Faculty of Engineering and Information Sciences - Papers: Part A

Fast parameter estimation is a non-trivial task, and it is critical when the system parameters evolve with time, as demanded in real-time control applications. In this study, a new computational approach for parameter identification is proposed based on the application of polynomial chaos theory. The polynomial chaos approach has been shown to be considerably more efficient than Monte Carlo in the simulation of systems with a small number of uncertain parameters. In the framework of this new approach, a (suboptimal) Extended Kalman Filter (EKF) is used to recalculate the polynomial chaos expansions for the uncertain states and the uncertain parameters. …


Extension Problems And Non-Abelian Duality For C*-Algebras, Astrid An Huef, S Kaliszewski, Iain Raeburn Jan 2007

Extension Problems And Non-Abelian Duality For C*-Algebras, Astrid An Huef, S Kaliszewski, Iain Raeburn

Faculty of Engineering and Information Sciences - Papers: Part A

Suppose that H is a closed subgroup of a locally compact group G. We show that a unitary representation U of H is the restriction of a unitary representation of G if and only if a dual representation Û of a crossed product C*(G) (G/H) is regular in an appropriate sense. We then discuss the problem of deciding whether a given representation is regular; we believe that this problem will prove to be an interesting test question in non-Abelian duality for crossed products of C*-algebras.


Five-Level Active Npc Converter Topology: She-Pwm Control And Operation Principles, Sridhar Reddy Pulikanti, Vassilios G. Agelidis Jan 2007

Five-Level Active Npc Converter Topology: She-Pwm Control And Operation Principles, Sridhar Reddy Pulikanti, Vassilios G. Agelidis

Faculty of Engineering and Information Sciences - Papers: Part A

The neutral-point-clamped (NPC) inverter topology has been the centre of research and development effort for numerous applications, including medium- and high-voltage electric motor drives, static compensators (STATCOMs) and other utility type of power electronic systems for almost three decades now. Pulse-width modulation (PWM) control methods have been developed for such topology for respective three-level and multilevel versions. The issue of voltage balancing between the DC bus capacitors is a drawback that requires attention and the problem becomes more serious as the number of levels increases. Selective harmonic elimination PWM can be applied to control the topology as a method to …