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Full-Text Articles in Engineering

A Nonlinear 1-D Case Backward Heat Problem: Regularization And Error, Dang Duc Trong, Pham Hoang Quan, Tran Vu Khanh, Nguyen Huy Tuan Jan 2007

A Nonlinear 1-D Case Backward Heat Problem: Regularization And Error, Dang Duc Trong, Pham Hoang Quan, Tran Vu Khanh, Nguyen Huy Tuan

Faculty of Engineering and Information Sciences - Papers: Part A

No abstract provided.


Rqf Publication Quality Measures: Methodological Issues, John W. Lamp, Simon K. Milton, Linda Dawson, Julie Fisher Jan 2007

Rqf Publication Quality Measures: Methodological Issues, John W. Lamp, Simon K. Milton, Linda Dawson, Julie Fisher

Faculty of Engineering and Information Sciences - Papers: Part A

The Research Quality Framework uses Thomson-ISI citation benchmarks as its main set of objective measures of research quality. The Thomson-ISI measures rely on identifying a core set of journals in which the major publications for a discipline are to be found. The core for a discipline is determined by applying a nontransparent process that is partly based on Bradford's Law (1934). Yet Bradford was not seeking measures about quality of publications or journals. How valid then is it to base measures of publication quality on Bradford's Law? We explore this by returning to Bradford's Law and subsequent related research asking …


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 …


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 …


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.


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 …


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.


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.


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 …


Thz Emission From Be-Doped Gaas, Stuart R. Hargreaves, R A. Lewis Jan 2007

Thz Emission From Be-Doped Gaas, Stuart R. Hargreaves, R A. Lewis

Faculty of Engineering and Information Sciences - Papers: Part A

Directing ultrashort near-infrared laser pulses between two electrodes on the surface of GaAs:Be may produce THz radiation. We have measured the generated THz signal as a function of the applied bias voltage, the optical excitation energy, and the beam size, for a series of samples of differing doping levels. The variation in THz signal with bias is approximately quadratic, as expected. In contrast, the variation of THz signal with optical excitation power is subquadratic. As determined by apertureless z-scans, the THz emission depends strongly on the excitation beam diameter. As the Be concentration is varied, the THz emission varies slightly …


Impact Of Using Different Models In Practice - A Case Study With The Simplified Methods Of Iso 13790 Standard And Detailed Modelling Programs, Georgios Kokogiannakis, Jo Clarke, Paul Strachan Jan 2007

Impact Of Using Different Models In Practice - A Case Study With The Simplified Methods Of Iso 13790 Standard And Detailed Modelling Programs, Georgios Kokogiannakis, Jo Clarke, Paul Strachan

Faculty of Engineering and Information Sciences - Papers: Part A

The updated ISO 13790 Standard is part of the new set of CEN Standards that supports the European Energy Performance of Buildings Directive (EPBD) requirement for a general framework for calculation of the energy consumption of buildings. The Standard sets out procedures for space heating and cooling energy calculations, allowing the use of three different methods: a simplified monthly quasi-steady state method, a simple-hourly method and detailed simulation. This paper examines the implications of allowing different methods to be used for assessing the energy usage. The research method used was to undertake a comparison of the various methods applied to …


Minimising Voltage Deviation In Distribution Feeders By Otpimising Size And Location Of Distributed Generation, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich Jan 2007

Minimising Voltage Deviation In Distribution Feeders By Otpimising Size And Location Of Distributed Generation, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich

Faculty of Engineering and Information Sciences - Papers: Part A

A new emerging trend of distribution networks is to use small generating units, known as distributed generation (DG), operating in parallel with the main grid. This kind of distribution networks has enabled DG to support power systems in fulfi lling their requirements to increase power output as well as quality of power supply. In order to maximise benefi ts from the DG system, proper DG planning is necessary. The main purpose of this research is to maximise voltage support through optimal sizing and location of DG. A new methodology is developed to determine an optimal DG size and DG location …


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.


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 …


Kinetics Of Transfemoral Amputees With Osseointegrated Fixation Performing Common Activities Of Daily Living, Winson Lee, Laurent A. Frossard, Kerstin Hagberg, Eva Haggstrom, Rickard Branemark, John H. Evans, Mark J. Pearcy Jan 2007

Kinetics Of Transfemoral Amputees With Osseointegrated Fixation Performing Common Activities Of Daily Living, Winson Lee, Laurent A. Frossard, Kerstin Hagberg, Eva Haggstrom, Rickard Branemark, John H. Evans, Mark J. Pearcy

Faculty of Engineering and Information Sciences - Papers: Part A

Direct anchorage of a lower-limb prosthesis to the bone through an implanted fixation (osseointegration) has been suggested as an excellent alternative for amputees experiencing complications from use of a conventional socket-type prosthesis. However, an attempt needs to be made to optimize the mechanical design of the fixation and refine the rehabilitation program. Understanding the load applied on the fixation is a crucial step towards this goal. METHODS: The load applied on the osseointegrated fixation of nine transfemoral amputees was measured using a load transducer, when the amputees performed activities which included straight-line level walking, ascending and descending stairs and a …


Numerical Simulation Of Temperature Field And Thermal Stress Field Of Work Roll During Hot Strip Rolling, Chang-Sheng Li, Hai-Liang Yu, Guan-Yu Deng, Xiang-Hua Liu, Guo-Dong Wang Jan 2007

Numerical Simulation Of Temperature Field And Thermal Stress Field Of Work Roll During Hot Strip Rolling, Chang-Sheng Li, Hai-Liang Yu, Guan-Yu Deng, Xiang-Hua Liu, Guo-Dong Wang

Faculty of Engineering and Information Sciences - Papers: Part A

Based on the thermal conduction equations, the three-dimensional (3D) temperature field of a work roll was investigated using finite element method (FEM). The variations in the surface temperature of the work roll during hot strip rolling were described, and the thermal stress field of the work roll was also analyzed. The results showed that the highest roll surface temperature is 593 °C, and the difference between the minimum and maximum values of thermal stress of the work roll surface is 145. 7 MPa. Furthermore, the results of this analysis indicate that temperature and thermal stress are useful parameters for the …


Influence Of Dog-Bone Apex On Shape During Slab Horizontal Rolling Process, Hai-Liang Yu, Xiang-Hua Liu, Chang-Sheng Li, Guo-Dong Wang Jan 2007

Influence Of Dog-Bone Apex On Shape During Slab Horizontal Rolling Process, Hai-Liang Yu, Xiang-Hua Liu, Chang-Sheng Li, Guo-Dong Wang

Faculty of Engineering and Information Sciences - Papers: Part A

The deformation of slab with dog-bone shape during the horizontal rolling process was simulated using FEM, and the influences of apical dislocation of dog-bone on the slab spread as well as the minimum crop end loss and the lost width at slab head and tail were analyzed. The results show that with the increase in the apical dislocation of dog-bone (LA), the slab spread and the minimum crop end loss at slab head and tail decrease, while the lost width at slab head and tail increases. Meanwhile, the relationships of S/LA-LA, LH/LA-LA, WH/LA-LA, LT/LA-LA, and WT/LA-LA were obtained. © 2007 …


Security Remarks On A Convertible Nominative Signature Scheme, Guilin Wang, Feng Bao Jan 2007

Security Remarks On A Convertible Nominative Signature Scheme, Guilin Wang, Feng Bao

Faculty of Engineering and Information Sciences - Papers: Part A

A nominative signature scheme allows a nominator (i.e. the signer) and a nominee (i.e. a designated verifier) to jointly generate and publish a signature so that only the nominee can check the validity of a nominative signature and further convince a third party to accept this fact. Recently, Huang and Wang proposed such a new scheme at ACISP 2004, and claimed that their scheme is secure under some standard computational assumptions. In this paper, we remark that their scheme is not a nominative signature in fact, since it fails to meet the crucial security requirement: verification untransferability. Specifically, we identify …


Security Analysis Of Two Ultra-Lightweight Rfid Authentication Protocols, Tieyan Li, Guilin Wang Jan 2007

Security Analysis Of Two Ultra-Lightweight Rfid Authentication Protocols, Tieyan Li, Guilin Wang

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, we analyze the security vulnerabilities of two ultra-lightweight RFID mutual authentication protocols: LMAP and M2AP, which are recently proposed by Peris-Lopez et al.We identify two e®ective attacks, namely De-synchronization attack and Full-disclosure attack, against their protocols. The former attack can break the synchro- nization between the RFID reader and the tag in a single protocol run so that they can not authenticate each other in any following protocol runs. The latter attack can disclose all the secret information stored on a tag by interrogating the tag multiple times. Thus it compromises the tag completely. Moreover, we point …


Doing It Tough: Factors Impacting On Local E-Government Mmaturity, Peter Shackleton, Linda Dawson Jan 2007

Doing It Tough: Factors Impacting On Local E-Government Mmaturity, Peter Shackleton, Linda Dawson

Faculty of Engineering and Information Sciences - Papers: Part A

As growing numbers of citizens seek to use the Internet to do business, governments across the world have moved into the area of electronic service delivery. For the last decade significant advancements have been made in the area of e-Government. Today, e-Government is often assumed to be wellestablished. However, ongoing support is often missing, particularly at the local government level. The multi-level nature of government often means that citizens are frustrated when accessing services that span many levels of bureaucracy. This paper describes an empirical study which explores the factors influencing local egovernment maturity and identifies the barriers, enablers, priorities …


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.