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Articles 2491 - 2520 of 2936
Full-Text Articles in Social and Behavioral Sciences
Gmp‐Based Channel Estimation For Single‐Carrier Transmissions Over Doubly Selective Channels, Qinghua Guo, Defeng (David) Huang
Gmp‐Based Channel Estimation For Single‐Carrier Transmissions Over Doubly Selective Channels, Qinghua Guo, Defeng (David) Huang
Faculty of Engineering and Information Sciences - Papers: Part A
We present a graph-based channel estimation approach for SC-IFDE (single-carrier transmissions with iterative frequency domain equalization) without CP (cyclic prefix) over doubly selective channels using the recently developed Gaussian message passing (GMP) technique. A direct application of the GMP updating rules in the FFG (Forney-style factor graph) of the SC-IFDE system model incurs high complexity. Approximate updating rules are therefore developed to overcome this problem. The proposed GMP-based channel estimation approach has similar complexity as the low-complexity Kalman-filtering based frequency domain channel estimation approach in the literature, but significantly outperforms the latter due to its enhanced capability in capturing the …
Model Tests On Free-Standing Passive Pile Groups In Sand, Wei-Dong Guo, E. H. Ghee
Model Tests On Free-Standing Passive Pile Groups In Sand, Wei-Dong Guo, E. H. Ghee
Faculty of Engineering and Information Sciences - Papers: Part A
A number of tests have been conducted to investigate response of vertically loaded capped pile groups in sand undergoing uniform lateral soil movement. The development of shear force, bending moment and deflection along the piles was measured. Presented in this paper are 4 tests on 2-pile free-standing groups, with a view to establish solutions for predicting the pile response. It was concluded that (1) maximum bending moment Mmax is largely linearly related to the sliding force Tmax in stable and moving layers; (2) The combined impact of pile-cap fixity, soil movement profiles, and axial load may be quantified by a …
Response Of 20 Laterally Loaded Piles In Sand, Wei-Dong Guo, Bi Tang Zhu
Response Of 20 Laterally Loaded Piles In Sand, Wei-Dong Guo, Bi Tang Zhu
Faculty of Engineering and Information Sciences - Papers: Part A
Closed-form solutions and their associated spreadsheet program (GASLFP) were developed by the first author for laterally loaded free- head piles in elastic-plastic media. The solutions show behaviour of a laterally loaded pile is dominated by net limiting force per unit length (LFP) fully mobilised along the pile to a depth called slip depth. They are characterised by three parameters of Ng, α o and n (to describe the LFP) and the soil shear modulus (Gs). Conversely, these parameters may be deduced by matching the predicted with measured response. To facilitate practical design, in this paper, the input values of Ng, …
Comparison Of Thermal Stability In Max211 And 312 Phases, Wei Kong Pang, It-Meng Low, B H. O'Connor, Andrew J. Studer, Vanessa Peterson, Zheng-Ming Sun, J P. Palmquist
Comparison Of Thermal Stability In Max211 And 312 Phases, Wei Kong Pang, It-Meng Low, B H. O'Connor, Andrew J. Studer, Vanessa Peterson, Zheng-Ming Sun, J P. Palmquist
Faculty of Engineering and Information Sciences - Papers: Part A
The susceptibility of four MAX phases (Ti2AlC, Cr2AlC, Ti3AlC2, and Ti3SiC2) to high-temperature thermal dissociation in vacuum has been investigated using in-situ neutron diffraction.
Impacts Of Coal Shrinkage, Permeability And Petrography On Gas Regime In Mines Case Study: Tahmoor Coal Mine, Nsw, Australia, Naj Aziz, Ian Porter, F Sereshki
Impacts Of Coal Shrinkage, Permeability And Petrography On Gas Regime In Mines Case Study: Tahmoor Coal Mine, Nsw, Australia, Naj Aziz, Ian Porter, F Sereshki
Faculty of Engineering and Information Sciences - Papers: Part A
The volumetric changes in the coal matrix (Coal Shrinkage), permeability under various gas environment conditions as well as perographical properties were studied in the laboratory. The shrinkage and permeability of coal were examined with respect to changing gas type and confining pressures. The shrinkage tests were carried out in high-pressure bombs while the permeability study was conducted in a specially constructed high-pressure chamber. Methane (CH4), carbon dioxide (CO2), nitrogen, (N2) and a 50%-50% volume mixture of CO2/CH4 gas were used in the study. The tests showed that under different pressure levels gas type affected permeability and shrinkage characteristics of coal. …
Simulation Of Macroscopic Deformation Using A Sub-Particle Dem Approach, Leela Kempton, David J. Pinson, Sheng Chew, Paul Zulli, Aibing Yu
Simulation Of Macroscopic Deformation Using A Sub-Particle Dem Approach, Leela Kempton, David J. Pinson, Sheng Chew, Paul Zulli, Aibing Yu
Faculty of Engineering and Information Sciences - Papers: Part A
A limitation in numerical modelling of the ironmaking blast furnace is the lack of ability to quantify the effects of particle deformation and subsequent loss of porosity arising from the softening and melting of ferrous materials. Previous attempts to consider deformation focussed solely on the macroscopic effects such as resistance to gas flow, with an assumed decrease in porosity proportional to temperature. Instead, it is proposed to approximate particle scale deformation using a modified subparticle Discrete Element Method approach, where each 'ore' particle is represented using an agglomerate of discrete elements with temperature dependent properties. Cohesive forces binding the agglomerate …
Dynamic Response Analysis Of The Rotating Blade Of Horizontal Axis Wind Turbine, Xiong Liu, Xianmin Zhang, Gangqiang Li, Yan Chen, Zhiquan Ye
Dynamic Response Analysis Of The Rotating Blade Of Horizontal Axis Wind Turbine, Xiong Liu, Xianmin Zhang, Gangqiang Li, Yan Chen, Zhiquan Ye
Faculty of Engineering and Information Sciences - Papers: Part A
This paper presents a dynamic response analysis of the blade of horizontal axis wind turbines using finite element method. The blade is treated as a cantilever and modeled with two-node beam element. The blade element-momentum theory is applied to calculate the aerodynamic loads. Dynamic inflow and dynamic stall are taken into account to reflect the transient aerodynamics. The centrifugal stiffening is introduced to consider the restoring effects of centrifugal force. An aerodynamic damping model is presented for calculating the overall damping ratio instantaneously during time-domain simulation. The structural dynamic equation is solved using Newmark method and the overall dynamic response …
Uniform Regularity In A Wedge And Regularity Of Traces Of Cr Functions, Luca Baracco, Stefano Pinton, Tran Vu Khanh
Uniform Regularity In A Wedge And Regularity Of Traces Of Cr Functions, Luca Baracco, Stefano Pinton, Tran Vu Khanh
Faculty of Engineering and Information Sciences - Papers: Part A
No abstract provided.
Finite Element Prediction Of Plate-End Cover Separation In Frp-Strengthened Rc Beams, S S. Zhang, J G. Teng
Finite Element Prediction Of Plate-End Cover Separation In Frp-Strengthened Rc Beams, S S. Zhang, J G. Teng
Faculty of Engineering and Information Sciences - Papers: Part A
The flexural strength of reinforced concrete (RC) beams can be effectively increased using either externally bonded (EB) or near-surface mounted (NSM) fibre-reinforced polymer (FRP) reinforcement. A likely failure mode of such FRP-strengthened RC beams is the plate-end cover separation failure mode which involves debonding of the bonded FRP reinforcement and the cover concrete along the level of the steel tension reinforcement. Despite many existing studies on this failure mode, the accurate prediction of this failure mode using the finite element (FE) method has remained a great challenge. This paper presents a novel FE smeared-crack approach for accurate prediction of plate-end …
High-Energy, Picosecond, Cryogenic Yb:Yag Chirped-Pulse Amplifier At Khz Repetition Rates For Opcpa Pumping, Kyung-Han Hong, Juliet Gopinath, Darren Rand, Aleem M. Siddiqui, Shu-Wei Huang, Enbang Li, Benjamin J. Eggleton, John D. Hybl, Tso Yee Fan, Franz X. Kartner
High-Energy, Picosecond, Cryogenic Yb:Yag Chirped-Pulse Amplifier At Khz Repetition Rates For Opcpa Pumping, Kyung-Han Hong, Juliet Gopinath, Darren Rand, Aleem M. Siddiqui, Shu-Wei Huang, Enbang Li, Benjamin J. Eggleton, John D. Hybl, Tso Yee Fan, Franz X. Kartner
Faculty of Engineering and Information Sciences - Papers: Part A
We report on the development of a 50-mJ-class ~10-ps chirped-pulse amplifier at kHz repetition rates using cryogenic Yb:YAG regenerative and multi-pass amplifiers. The system is well suited as pump laser for kHz high-average-power ultra-broadband OPCPAs. '2010 Optical Society of America
Ultrabroadband Optical Parametric Chirped Pulse Amplifier System For Single-Cycle Waveform Synthesis, Shu-Wei Huang, Giovanni Cirmi, Jeffrey Moses, Kyung-Han Hong, Andrew Benedick, Li-Jin Chen, Enbang Li, Benjamin J. Eggleton, Giulio Cerullo, Franz X. Kartner
Ultrabroadband Optical Parametric Chirped Pulse Amplifier System For Single-Cycle Waveform Synthesis, Shu-Wei Huang, Giovanni Cirmi, Jeffrey Moses, Kyung-Han Hong, Andrew Benedick, Li-Jin Chen, Enbang Li, Benjamin J. Eggleton, Giulio Cerullo, Franz X. Kartner
Faculty of Engineering and Information Sciences - Papers: Part A
We demonstrate synchronized few-cycle 800-nm and 2-μm pulse trains seeded from a single Ti:sapphire oscillator, able to generate scalable, high-energy pulses lasting less than a single electric-field cycle. Such pulses are attractive for high-field physics.
Mechanism Of Sediment Transport In Uni-Directional, Bi-Directional Flows, Shu-Qing Yang
Mechanism Of Sediment Transport In Uni-Directional, Bi-Directional Flows, Shu-Qing Yang
Faculty of Engineering and Information Sciences - Papers: Part A
The aim of the present study is to investigate the relationship between flow strength and sediment discharge. The appropriate definition of energy dissipation rate E in Bagnold's theorem is discussed and it is found that the sediment transport rate g, in unidirectional and bi-directional flows can be well predicted when E is defined as the product of bed shear stress T. and near bed velocity u. then the linear relationship between u. E and the sediment transport rate is examined using measured data. The good agreement between measured and predicted values indicates that the phenomena of sediment transport can be …
Thrust And Bending Moment Of Rigid Piles Subjected To Moving Soil, Wei-Dong Guo, H Y. Qin
Thrust And Bending Moment Of Rigid Piles Subjected To Moving Soil, Wei-Dong Guo, H Y. Qin
Faculty of Engineering and Information Sciences - Papers: Part A
An experimental apparatus was developed to investigate the behaviour of vertically loaded free-head piles in sand undergoing lateral soil movement(wf). A large number of tests have been conducted to date. Presented herein are 14 typical model pile tests concerning 2 diameters, 2 vertical pile loading levels, and varying sliding depths with the movement Wf driven by a triangular loading block. The results are provided regarding driving force, and induced shear force (T), bending movement (M) and deflection (y) along the piles with Wf/ normalised sliding depth. The tests enable simple expressions to be proposed, capitalised on theory for laterally loaded …
Statistical Interpolation Methods, Richard Smith, Noel A. Cressie
Statistical Interpolation Methods, Richard Smith, Noel A. Cressie
Faculty of Engineering and Information Sciences - Papers: Part A
Statistical methods of interpolation are all based on assuming that the process being reconstructed (for the purpose of this report, a temperature field in space or time or both) can be modeled as a random process. The best-known examples occur in spatial statistics, including the technique widely known as kriging, and in time series analysis. The process may depend on unknown parameters, which have to be estimated as part of the interpolation procedure. Once the process is specified, including any estimated parameters, optimal interpolators are calculated either by finding the best linear interpolator (the linear combination of known observations that …
Where To Place Product Reviews? An Information Search Process Perspective, Mengxiang Li, Chuan-Hoo Tan, Kwok-Kee Wei, Kanliang Wang
Where To Place Product Reviews? An Information Search Process Perspective, Mengxiang Li, Chuan-Hoo Tan, Kwok-Kee Wei, Kanliang Wang
Faculty of Engineering and Information Sciences - Papers: Part A
Online product reviews could be presented as expert reviews and user reviews. However, a fundamental question that is not fully understood, and which this study addresses, is: Where should product reviews be displayed so as to positively affect a consumer's decision-making performance? We focus on evaluating the impact of the placements and the source of reviews (i.e., the pre-screening or post-screening display of experts' or users' comments) on consumer behavior. Building on the underpinnings of Kuhlthau's model of information search process, we propose that the Expert-User product review provision (i.e., placing the expert reviews before the screening stage and the …
Organisational Culture And Organisational Impacts Of Information Systems: A Review Of The Empirical Literature, Fei Peng, Rajeev Sharma, Sherah Kurnia, Reeva Lederman, Suelette Dreyfus
Organisational Culture And Organisational Impacts Of Information Systems: A Review Of The Empirical Literature, Fei Peng, Rajeev Sharma, Sherah Kurnia, Reeva Lederman, Suelette Dreyfus
Faculty of Engineering and Information Sciences - Papers: Part A
Organisational culture is an important influence in shaping the organisational impacts of Information Systems. However, the conceptualisation and operationalisation of culture in empirical studies does not reflect the richness of the theoretical literature. In particular, our review finds that the dynamic, emergent and reciprocal nature of the IS-culture relationship has not been adequately examined in the empirical literature. This is partly due to the methodologies employed in existing research. Suggestions for enriching empirical research into the ISculture relationship are discussed.
Harmonic Elimination Control Of A Five-Level Dc-Ac Cascaded H-Bridge Hybrid Inverter, Georgios S. Konstantinou, Sridhar R. Pulikanti, Vassilios G. Agelidis
Harmonic Elimination Control Of A Five-Level Dc-Ac Cascaded H-Bridge Hybrid Inverter, Georgios S. Konstantinou, Sridhar R. Pulikanti, Vassilios G. Agelidis
Faculty of Engineering and Information Sciences - Papers: Part A
A five-level hybrid cascaded inverter operating under selective harmonic elimination (SHE) pulse-width modulation (PWM) control is discussed in this paper. The topology is a cascaded connection of a conventional three-phase, two-level inverter and an H-bridge module for each phase with a single DC-source. The topology boosts the output voltage within limits and with no additional DC-DC converters. However, such boosting feature depends on the control of the floating capacitor voltage and the load power factor. The regulation of the floating capacitor for the given modulation strategy is also analyzed. Experimental results taken from a single-phase laboratory prototype are presented to …
The Impact Of Strategy And Maturity On Business Analytics And Firm Performance: A Review And Research Agenda, Graeme Shanks, Rajeev Sharma, Peter Seddon, Peter Reynolds
The Impact Of Strategy And Maturity On Business Analytics And Firm Performance: A Review And Research Agenda, Graeme Shanks, Rajeev Sharma, Peter Seddon, Peter Reynolds
Faculty of Engineering and Information Sciences - Papers: Part A
Business analytics involves interpreting organizational data to improve decision-making and to optimise business processes. It has the potential to improve firm performance and increase competitive advantage. Although many case studies have been reponed that describe business analytics applications and speculate about how they might contribute to firm performance, there is no clearly articulated and theoretically grounded model in the literature. This paper proposes a theoretical framework jor understanding how and why business analytics technology and capabilities can lead to value-creating actions that lead to improved form performance and competitive advantage. We jocus particularly on how strategy and maturity impact business …
Feature Selection With Redundancy-Constrained Class Separability, Luping Zhou, Lei Wang, Chunhua Shen
Feature Selection With Redundancy-Constrained Class Separability, Luping Zhou, Lei Wang, Chunhua Shen
Faculty of Engineering and Information Sciences - Papers: Part A
Scatter-matrix-based class separability is a simple and efficient feature selection criterion in the literature. However, the conventional trace-based formulation does not take feature redundancy into account and is prone to selecting a set of discriminative but mutually redundant features. In this brief, we first theoretically prove that in the context of this trace-based criterion the existence of sufficiently correlated features can always prevent selecting the optimal feature set. Then, on top of this criterion, we propose the redundancy-constrained feature selection (RCFS). To ensure the algorithm's efficiency and scalability,we study the characteristic of the constraints with which the resulted constrained 0-1 …
On Pogorelov Estimates For Monge-Ampere Type Equations, Jiakun Liu, Neil Trudinger
On Pogorelov Estimates For Monge-Ampere Type Equations, Jiakun Liu, Neil Trudinger
Faculty of Engineering and Information Sciences - Papers: Part A
In this paper, we prove interior second derivative estimates of Pogorelov type for a general form of Monge-Ampère equation which includes the optimal transportation equation. The estimate extends that in a previous work with Xu-Jia Wang and assumes only that the matrix function in the equation is regular with respect to the gradient variables, that is it satisfies a weak form of the condition introduced previously by Ma,Trudinger and Wang for regularity of optimal transport mappings. We also indicate briefly an application to optimal transportation.
Iterative Soft Compensation For Ofdm Systems With Clipping And Superposition Coded Modulation, Jun Tong, Li Ping, Zhonghao Zhang, Vijay Bhargava
Iterative Soft Compensation For Ofdm Systems With Clipping And Superposition Coded Modulation, Jun Tong, Li Ping, Zhonghao Zhang, Vijay Bhargava
Faculty of Engineering and Information Sciences - Papers: Part A
This paper deals with the clipping method used in orthogonal frequency-division multiplexing (OFDM) systems to reduce the peak-to-average power ratio (PAPR). An iterative soft compensation method is proposed to mitigate the clipping distortion, which can outperform conventional treatments. The impact of signaling schemes on the residual clipping noise power is studied via the symbol variance analysis. It is found that superposition coded modulation (SCM) can minimize the residual clipping noise power among all possible signaling schemes. This indicates that SCM-based OFDM systems are more robust to clipping effect than other alternatives when soft compensation is applied. It is also shown …
A Λ-Cut And Goal-Programming-Based Algorithm For Fuzzy-Linear Multiple-Objective Bilevel Optimization, Ya Gao, Guangquan Zhang, Jun Ma, Jie Lu
A Λ-Cut And Goal-Programming-Based Algorithm For Fuzzy-Linear Multiple-Objective Bilevel Optimization, Ya Gao, Guangquan Zhang, Jun Ma, Jie Lu
Faculty of Engineering and Information Sciences - Papers: Part A
Bilevel-programming techniques are developed to handle decentralized problems with two-level decision makers, which are leaders and followers, who may have more than one objective to achieve. This paper proposes a λ-cut and goal-programming-based algorithm to solve fuzzy-linear multiple-objective bilevel (FLMOB) decision problems. First, based on the definition of a distance measure between two fuzzy vectors using λ-cut, a fuzzy-linear bilevel goal (FLBG) model is formatted, and related theorems are proved. Then, using a λ-cut for fuzzy coefficients and a goal-programming strategy for multiple objectives, a λ-cut and goal-programming-based algorithm to solve FLMOB decision problems is presented. A case study for …
Efficient Structured Support Vector Regression, Ke Jia, Lei Wang, Nianjun Liu
Efficient Structured Support Vector Regression, Ke Jia, Lei Wang, Nianjun Liu
Faculty of Engineering and Information Sciences - Papers: Part A
Support Vector Regression (SVR) has been a long standing problem in machine learning, and gains its popularity on various computer vision tasks. In this paper, we propose a structured support vector regression framework by extending the max-margin principle to incorporate spatial correlations among neighboring pixels. The objective function in our framework considers both label information and pairwise features, helping to achieve better cross-smoothing over neighboring nodes. With the bundle method, we effectively reduce the number of constraints and alleviate the adverse effect of outliers, leading to an efficient and robust learning algorithm. Moreover, we conduct a thorough analysis for the …
Hippocampal Shape Classification Using Redundancy Constrained Feature Selection, Luping Zhou, Lei Wang, Chunhua Shen, Nick Barnes
Hippocampal Shape Classification Using Redundancy Constrained Feature Selection, Luping Zhou, Lei Wang, Chunhua Shen, Nick Barnes
Faculty of Engineering and Information Sciences - Papers: Part A
Landmark-based 3D hippocampal shape classification involves high-dimensional descriptor space, many noisy and redundant features, and a very small number of training samples. Feature selection becomes critical in this situation, because it not only improves classification performance, but also identifies the regions that contribute more to shape discrimination. This work identifies the drawbacks of SVM-RFE, and proposes a novel class-separability-based feature selection approach to overcome them. We formulate feature selection as a constrained integer optimization and develop a new algorithm to efficiently and optimally solve this problem. Theoretical analysis and experimental study on both synthetic data and real hippocampus data demonstrate …
Stabilisation Of An Erodible Soil Using A Chemical Admixture, Jayan S. Vinod, B Indraratna, Md A. Al Mahamud
Stabilisation Of An Erodible Soil Using A Chemical Admixture, Jayan S. Vinod, B Indraratna, Md A. Al Mahamud
Faculty of Engineering and Information Sciences - Papers: Part A
Internal erosional behaviour of a lignosulfonate-treated dispersive soil has been studied using apparatus designed and built at University of Wollongong. The effectiveness of lignosulfonate-treated dispersive clay on its erosion resistance has been investigated and its advantages over traditional admixtures (cement) have been presented. Lignosulfonate is a non-toxic admixture that can stabilise certain erodible and dispersive soils effectively, without causing any adverse environmental impact on the ground unlike some traditional stabilisers. Test results show that the erosional parameters such as critical shear stress and coefficient of soil erosion are improved with the increase in the amount of lignosulfonate. Knowledge about the …
Coastal Reservoir In Murray-Darling River And Its Useful Experience For Yellow River, Shu-Qing Yang
Coastal Reservoir In Murray-Darling River And Its Useful Experience For Yellow River, Shu-Qing Yang
Faculty of Engineering and Information Sciences - Papers: Part A
this paper deals with the similarities between the Yellow River Basin and Murray - Darling River Basin. It is found that two of them are facing similar problems, such as water shortage, poor quality for water supply and decreasing runoff etc. Two basins suffer the sharp temporal and spatial variation in water resources, which results in flood threat and water stress alternatively. Consequently these two rivers have attracted global attention due to their significant impacts on their local economical development and ecological system. To alleviate the water stress conditions, this paper investigates the feasibility of coastal reservoirs at the river …
Discriminative Maximum Margin Image Object Categorization With Exact Inference, Qinfeng Shi, Luping Zhou, Li Cheng, Dale Schuurmans
Discriminative Maximum Margin Image Object Categorization With Exact Inference, Qinfeng Shi, Luping Zhou, Li Cheng, Dale Schuurmans
Faculty of Engineering and Information Sciences - Papers: Part A
Categorizing multiple objects in images is essentially a structured prediction problem: the label of an object is in general dependent on the labels of other objects in the image. We explicitly model object dependencies in a sparse graphical topology induced by the adjacency of objects in the image, which benefits inference, and then use maximum margin principle to learn the model discriminatively. Moreover, we propose a novel exact inference method, which is used in training to find the most violated constraint required by cutting plane method. A slightly modified inference method is used in testing when the target labels are …
Seven-Level Cascaded Anpc-Based Multilevel Converter, Sridhar R. Pulikanti, Georgios S. Konstantinou, Vassilios G. Agelidis
Seven-Level Cascaded Anpc-Based Multilevel Converter, Sridhar R. Pulikanti, Georgios S. Konstantinou, Vassilios G. Agelidis
Faculty of Engineering and Information Sciences - Papers: Part A
A seven-level converter based on the cascaded connection of a three-level active neutral-point-clamped (ANPC) converter and individual H-bridge cells per phase is presented in this paper. This converter only requires a single DC source for all three phases and extends the amplitude of output voltage of the converter with similar DC-link voltage. The operation principles and control strategies based on a fundamental frequency harmonic elimination PWM are discussed. The regulation of FC voltage depends on the positions of switching angles over a quarter period in the available solutions and on the load power factor. In order to extend the regulation …
Noncommutative Atiyah-Patodi-Singer Boundary Conditions And Index Pairings In Kk-Theory, Alan L. Carey, John Phillips, Adam C. Rennie
Noncommutative Atiyah-Patodi-Singer Boundary Conditions And Index Pairings In Kk-Theory, Alan L. Carey, John Phillips, Adam C. Rennie
Faculty of Engineering and Information Sciences - Papers: Part A
We investigate an extension of ideas of Atiyah-Patodi-Singer (APS) to a noncommutative geometry setting framed in terms of Kasparov modules. We use a mapping cone construction to relate odd index pairings to even index pairings with APS boundary conditions in the setting of KK-theory, generalising the commutative theory. We find that Cuntz-Krieger systems provide a natural class of examples for our construction and the index pairings coming from APS boundary conditions yield complete K-theoretic information about certain graph C*-algebras
Twisted Cyclic Theory And An Index Theory For The Gauge Invariant Kms State On Cuntz Algebras On, Alan L. Carey, John Phillips, Adam C. Rennie
Twisted Cyclic Theory And An Index Theory For The Gauge Invariant Kms State On Cuntz Algebras On, Alan L. Carey, John Phillips, Adam C. Rennie
Faculty of Engineering and Information Sciences - Papers: Part A
This paper presents, by example, an index theory appropriate to algebras without trace. Whilst we work exclusively with the Cuntz algebras the exposition is designed to indicate how to develop a general theory. Our main result is an index theorem (formulated in terms of spectral flow) using a twisted cyclic cocycle where the twisting comes from the modular automorphism group for the canonical gauge action on the Cuntz algebra. We introduce a modified K1-group of the Cuntz algebra so as to pair with this twisted cocycle. As a corollary we obtain a noncommutative geometry interpretation for Araki's notion of relative …