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Coastal Reservoir In Murray-Darling River And Its Useful Experience For Yellow River, Shu-qing Yang 2010 University of Wollongong

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 mouths ...


Computational Intelligence For Carbon-Centric Computing, John Fulcher 2010 University of Wollongong

Computational Intelligence For Carbon-Centric Computing, John Fulcher

Faculty of Engineering and Information Sciences - Papers: Part A

The focus of this paper is twofold: firstly we make a case for the use of Computational Intelligence (CI) techniques in the modelling and/or prediction of global weather, CO2 emissions, climate change and similar endeavours. CI exploits processes found in Nature, albeit by way of software simulations on digital computers (i.e. in silico), and excel in particular at pattern recognition and/or classification. Moreover, they are characterized as being non-algorithmic, bottom-up, data-driven, and learn-by-example. The second focus of this paper is to propose the use of carbonrather than silicon-based computing, specifically in the form of DNA (or molecular ...


Liner Shipping Fleet Deployment With Cargo Transshipment And Demand Uncertainty, S Wang, Q Meng 2010 National University of Singapore

Liner Shipping Fleet Deployment With Cargo Transshipment And Demand Uncertainty, S Wang, Q Meng

Faculty of Engineering and Information Sciences - Papers: Part A

This paper addresses a novel liner shipping fleet deployment problem characterized by cargo transshipment, multiple container routing options and uncertain demand, with the objective of maximizing the expected profit. This problem is formulated as a stochastic program and solved by the sample average approximation method. In this technique the objective function of the stochastic program is approximated by a sample average estimate derived from a random sample, and then the resulting deterministic program is solved. This process is repeated with different samples to obtain a good candidate solution along with the statistical estimate of its optimality gap. We apply the ...


Influence Of Hydrogen Content On Hot Deformation Behavior And Microstructural Evolution Of Ti600 Alloy, J W. Zhao, H Ding, H L. Hou, Z Q. Li 2010 Northeastern University

Influence Of Hydrogen Content On Hot Deformation Behavior And Microstructural Evolution Of Ti600 Alloy, J W. Zhao, H Ding, H L. Hou, Z Q. Li

Faculty of Engineering and Information Sciences - Papers: Part A

Isothermal hot compression tests of a Ti600 alloy after hydrogenation were carried out over the temperature range of 760 to 880℃ and strain rate range of 0.01 to 10 s-1. The influence of hydrogen content was studied on the flow stress and activation energy of deformation. The microstructural changes were examined by transmission electron microscopy (TEM). The results show that the addition of 0.3% hydrogen in Ti600 alloy can decrease the hot deformation temperature by 80 ◦C and increase the deformation strain rate by two orders of magnitude. Both the flow stress and activation energy of deformation of ...


On Pogorelov Estimates For Monge-Ampere Type Equations, Jiakun Liu, Neil Trudinger 2010 University of Wollongong

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.


Noncommutative Atiyah-Patodi-Singer Boundary Conditions And Index Pairings In Kk-Theory, Alan L. Carey, John Phillips, Adam C. Rennie 2010 Australian National University

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


Hippocampal Shape Classification Using Redundancy Constrained Feature Selection, Luping Zhou, Lei Wang, Chunhua Shen, Nick Barnes 2010 Australian National University

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 ...


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 2010 Australian National University

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 ...


Stabilisation Of An Erodible Soil Using A Chemical Admixture, Jayan S. Vinod, B Indraratna, Md A. Al Mahamud 2010 University of Wollongong

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 ...


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 2010 University of Melbourne

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 ...


A Critique Of The Marker Variable Technique: The Effect Of Alternative Marker Variable Criteria, Rajeev Sharma, Philip Yetton, Jeff Crawford 2010 University of Melbourne

A Critique Of The Marker Variable Technique: The Effect Of Alternative Marker Variable Criteria, Rajeev Sharma, Philip Yetton, Jeff Crawford

Faculty of Engineering and Information Sciences - Papers: Part A

The marker variable technique offers a practical and easy method to address the validity threat on account of common method variance to the findings of individual studies. Hawever, the validity of the marker variable technique has not been established. This paper examines the validity threat to the marker variable technique arising from multiple criteria for the selection of the marker variable proposed in the literature. Our findings shaw that the conclusions that can be drawn under different criteria are significantly and substantially different, raising doubts about the validity of the marker variable technique. Proposals for developing theoretically grounded criteria for ...


An N-Level Flying Capacitor Based Active Neutral-Point-Clamped Converter, Sridhar R. Pulikanti, Georgios S. Konstantinou, Vassilios G. Agelidis 2010 University of Sydney

An N-Level Flying Capacitor Based Active Neutral-Point-Clamped Converter, Sridhar R. Pulikanti, Georgios S. Konstantinou, Vassilios G. Agelidis

Faculty of Engineering and Information Sciences - Papers: Part A

An n-level flying capacitor (FC) based active neutral point clamped (ANPC) converter is discussed in this paper. The converter is based on an arrangement of a three-level ANPC converter and a number of two-level cells creating an n-level line-to-neutral waveform. The converter is operated under a phase-shifted carrier pulse-width modulation (PWM). The mathematical model for the DC-link capacitors voltage behavior of a three-phase arrangement is also presented. It is shown through simulations and experimental work that the voltage of flying capacitors can naturally balance to the required level in order to generate multilevel waveform. Simulations and experimental work of a ...


Harmonic Elimination Control Of A Five-Level Dc-Ac Cascaded H-Bridge Hybrid Inverter, Georgios S. Konstantinou, Sridhar R. Pulikanti, Vassilios G. Agelidis 2010 University Of New South Wales

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 ...


Organisational Culture And Organisational Impacts Of Information Systems: A Review Of The Empirical Literature, Fei Peng, Rajeev Sharma, Sherah Kurnia, Reeva Lederman, Suelette Dreyfus 2010 University Of Melbourne

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.


Seven-Level Cascaded Anpc-Based Multilevel Converter, Sridhar R. Pulikanti, Georgios S. Konstantinou, Vassilios G. Agelidis 2010 University of Sydney

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 ...


Discriminative Maximum Margin Image Object Categorization With Exact Inference, Qinfeng Shi, Luping Zhou, Li Cheng, Dale Schuurmans 2010 Australian National University

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 ...


The Ideal Structure Of Reduced Crossed Products, Adam Sierakowski 2010 University of Southern Denmark

The Ideal Structure Of Reduced Crossed Products, Adam Sierakowski

Faculty of Engineering and Information Sciences - Papers: Part A

Let (A, G) be a C*-dynamical system with G discrete. In this paper we investigate the ideal structure of the reduced crossed product C*-algebra and in particular we determine sufficient—and in some cases also necessary—conditions for A to separate the ideals in A ⋊r G. When A separates the ideals in A ⋊r G, then there is a one-to-one correspondence between the ideals in A ⋊r G and the invariant ideals in A. We extend the concept of topological freeness and present a generalization of the Rokhlin property. Exactness properties of (A, G) turns out to ...


Investigation Of High Resolution Compact Gamma Camera Module Based On A Continuous Scintillation Crystal Using A Novel Charge Division Readout Method, Qiu-Sheng Dai, Cui-Lan Zhao, Hualin Zhang, Yujin Qi 2010 Chinese Academy Of Sciences

Investigation Of High Resolution Compact Gamma Camera Module Based On A Continuous Scintillation Crystal Using A Novel Charge Division Readout Method, Qiu-Sheng Dai, Cui-Lan Zhao, Hualin Zhang, Yujin Qi

Faculty of Engineering and Information Sciences - Papers: Part A

The objective of this study is to investigate a high performance and lower cost compact gamma camera module for a multi-head small animal SPECT system. A compact camera module was developed using a thin Lutetium Oxyorthosilicate (LSO) scintillation crystal slice coupled to a Hamamatsu H8500 position sensitive photomultiplier tube (PSPMT). A two-stage charge division readout board based on a novel sub-tractive resistive readout with a truncated center-of-gravity (TCOG) positioning method was developed for the camera. The performance of the camera was evaluated using a flood 99mTc source with a four-quadrant bar-mask phantom. The preliminary experimental results show that the image ...


Iterative Soft Compensation For Ofdm Systems With Clipping And Superposition Coded Modulation, Jun Tong, Li Ping, Zhonghao Zhang, Vijay Bhargava 2010 University of Newcastle

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 ...


High-Energy, Khz-Repetition-Rate, Ps Cryogenic Yb:Yag Chirped-Pulse Amplifier, 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 2010 Massachusetts Institute of Technology

High-Energy, Khz-Repetition-Rate, Ps Cryogenic Yb:Yag Chirped-Pulse Amplifier, 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 demonstrate amplification of picosecond laser pulses to 40 mJ at a 2 kHz pulse repetition frequency (PRF) from a two-stage cryogenic chirped-pulse Yb:YAG amplifier, composed of a regenerative amplifier (RGA) and a two-pass booster amplifier. The RGA produces 8.2 mJ of energy at 2 kHz PRF and 13.2 mJ at 1 kHz PRF with excellent energy stability (~0.3% rms) and beam quality ( M2<1.1 ). Pulse stretching and compression are achieved by using a chirped fiber Bragg grating and a multilayer dielectric grating pair, respectively. Compressed 15 ps pulses from the RGA are obtained with a throughput efficiency of ~80% (~6.5 mJ for 2 kHz ). The booster amplifier further amplifies the pulses to 40 mJ at 2 kHz PRF, and ~32 mJ, ~15 ps pulses are expected after compression. The amplifier chain seeded from a femtosecond Yb-fiber laser enables the optical self-synchronization between signal and pump in optical parametric chirped-pulse amplifier applications.


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