# Social and Behavioral Sciences Commons™

Faculty of Engineering and Information Sciences - Papers: Part A

2006

Articles 1 - 30 of 46

## Full-Text Articles in Social and Behavioral Sciences

The Use Of Maple Platform For The Study Of Geodisc Motion On Curved Spacetimes, Dumitru N. Vulcanov, Valentina D. Wheeler Jan 2006

#### The Use Of Maple Platform For The Study Of Geodisc Motion On Curved Spacetimes, Dumitru N. Vulcanov, Valentina D. Wheeler

##### Faculty of Engineering and Information Sciences - Papers: Part A

The article illustrates the graphical study of geodesic motion on curved space-times (mainly exact solutions of Einstein equations) using the symbolic, numerical and graphical computation facilities of Maple platform. The example of null geodesics on Schwarzschild solution is completely processed. The geodesic curves are plotted directly using DEtools package in Schwarzschild coordinates.

Exel's Crossed Product And Relative Cuntz-Pimsner Algebras, Nathan Brownlowe, Iain Raeburn Jan 2006

#### Exel's Crossed Product And Relative Cuntz-Pimsner Algebras, Nathan Brownlowe, Iain Raeburn

##### Faculty of Engineering and Information Sciences - Papers: Part A

We consider Exel's new construction of a crossed product of a $C^*$-algebra $A$ by an endomorphism $\alpha$. We prove that this crossed product is universal for an appropriate family of covariant representations, and we show that it can be realised as a relative Cuntz-Pimsner algbera. We describe a necessary and sufficient condition for the canonical map from $A$ into the crossed product to be injective, and present several examples to demonstrate the scope of this result. We also prove a gauge-invariant uniqueness theorem for the crossed product.

The Effect Of Small Business Clusters In Prioritising Barriers To E-Commerce Adoption In Regional Smes, Robert Macgregor, Lejla Vrazalic Jan 2006

#### The Effect Of Small Business Clusters In Prioritising Barriers To E-Commerce Adoption In Regional Smes, Robert Macgregor, Lejla Vrazalic

##### Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents a study of Swedish regional small businesses which investigated the barriers to E-commerce adoption (amongst other things). The aim of the paper is twofold: to examine the correlation between barriers to E-commerce adoption in order to identify underlying factors: and to determine whether these differ between SMEs that are members of a small business cluster and SMEs that are not. The paper begins by examining the nature of SMEs and identifying features that are unique to SMEs. A discussion of barriers to E-commerce adoption based on previous research is then presented and the barriers are mapped to …

Reply To Comment By M. Bayani Cardenas And John L. Wilson On "Flow Resistance And Bed Form Geometry In A Wide Alluvial Channel", Shu-Qing Yang, Soon-Keat Tan, Siow-Yong Lim Jan 2006

#### Reply To Comment By M. Bayani Cardenas And John L. Wilson On "Flow Resistance And Bed Form Geometry In A Wide Alluvial Channel", Shu-Qing Yang, Soon-Keat Tan, Siow-Yong Lim

##### Faculty of Engineering and Information Sciences - Papers: Part A

The authors would like to thank Cardenas and Wilson [2006] for their valuable comments and interesting discussions.

Chandra Observations Of Nuclear Outflows In The Elliptical Galaxy Ngc 4552 In The Virgo Cluster, M Machacek, Paul E. J Nulsen, C Jones, W R. Forman Jan 2006

#### Chandra Observations Of Nuclear Outflows In The Elliptical Galaxy Ngc 4552 In The Virgo Cluster, M Machacek, Paul E. J Nulsen, C Jones, W R. Forman

##### Faculty of Engineering and Information Sciences - Papers: Part A

We use a 54.4 ks Chandra observation to study nuclear outflow activity in NGC 4552 (M89), an elliptical galaxy in the Virgo Cluster. Chandra images in the 0.5–2 keV band show two ringlike features ∼1.7 kpc in diameter in the core of NGC 4552, as reported previously by Filho et al. We use spherically symmetric point explosion shock models to argue that the shape of the surface brightness profile across the rims of the rings and the temperature of hot gas in the rings are consistent with a Mach 1.7 shock carrying mean mechanical power Lshock ∼ 3 × 1041 …

Large Amplitude Nematicon Propagation In A Liquid Crystal With Local Response, Catherine Garcia-Reimbert, Antonmaria Minzoni, Noel Smyth, Annette L. Worthy Jan 2006

#### Large Amplitude Nematicon Propagation In A Liquid Crystal With Local Response, Catherine Garcia-Reimbert, Antonmaria Minzoni, Noel Smyth, Annette L. Worthy

##### Faculty of Engineering and Information Sciences - Papers: Part A

The evolution of polarized light in a nematic liquid crystal whose directors have a local response to reorienta-tion by the light is analyzed for arbitrary input light power. Approximate equations describing this evolution are derived based on a suitable trial function in a Lagrangian formulation of the basic equations governing the electric fields involved. It is shown that the nonlinearity of the material response is responsible for the forma-tion of solitons, so-called nematicons, by saturating the nonlinearity of the governing nonlinear Schrödinger equation. Therefore in the local material response limit, solitons are formed due to the nonlinear saturation behavior. It …

A Dual Graph Construction For Higher-Rank Graphs, And K-Theory For Finite 2-Graphs, Stephen Allen, David Pask, Aidan Sims Jan 2006

#### A Dual Graph Construction For Higher-Rank Graphs, And K-Theory For Finite 2-Graphs, Stephen Allen, David Pask, Aidan Sims

##### Faculty of Engineering and Information Sciences - Papers: Part A

Given a k-graph Λ and an element p of Nk, we define the dual k-graph, pΛ. We show that when Λ is row-finite and has no sources, the C*-algebras C*(Λ) and C*(pΛ) coincide. We use this isomorphism to apply Robertson and Steger's results to calculate the K-theory of C*(Λ) when Λ is finite and strongly connected and satisfies the aperiodicity condition.

Jacket Matrices Constructed From Hadamard Matrices And Generalized Hadamard Matrices, Ken Finlayson, Moon Ho Lee, Jennifer Seberry, Mieko Yamada Jan 2006

#### Jacket Matrices Constructed From Hadamard Matrices And Generalized Hadamard Matrices, Ken Finlayson, Moon Ho Lee, Jennifer Seberry, Mieko Yamada

##### Faculty of Engineering and Information Sciences - Papers: Part A

Behavior Of Transversal Crack On Slab Corner During V-H Rolling Process, Hai-Liang Yu, Xiang-Hua Liu, Chang-Sheng Li, Y Kusaba Jan 2006

#### Behavior Of Transversal Crack On Slab Corner During V-H Rolling Process, Hai-Liang Yu, Xiang-Hua Liu, Chang-Sheng Li, Y Kusaba

##### Faculty of Engineering and Information Sciences - Papers: Part A

The behavior of transversal cracks on the surface of the slab corner during vertical and horizontal (V-H) rolling process with flat vertical roll and groove vertical roll was simulated by explicit dynamic finite element method. The closure and growth of crack and the contact pressure on surfaces of the crack in contacting zone between slab and roll during rolling process were analyzed. The results showed that during vertical rolling process, when the groove vertical roll is used, the maximum contact pressure on surfaces of the crack is 115 MPa, and the closure of crack is stable; when the flat vertical …

Explicit Dynamic Fem Analysis Of Multipass Vertical-Horizontal Rolling, Hai-Liang Yu, Xiang-Hua Liu, Xian-Ming Zhao, Di Wu, Y Kusaba Jan 2006

#### Explicit Dynamic Fem Analysis Of Multipass Vertical-Horizontal Rolling, Hai-Liang Yu, Xiang-Hua Liu, Xian-Ming Zhao, Di Wu, Y Kusaba

##### Faculty of Engineering and Information Sciences - Papers: Part A

Three passes of plate rolling during vertical-horizontal rolling process are simulated with explicit dynamic finite element method and updating geometric method. The equivalent strain and stress fields, and shape change at the head and tail of slab during rolling are obtained. The calculated result of the shape at the head and tail of slab is in good agreement with the measured one. The explicit dynamic finite element method and updating geometric method can be used effectively to analyze the multipass vertical-horizontal (V-H) rolling process. © 2006 Central Iron and Steel Research Institute.

Distributed Generation Control Using Protection Principles, An D. T Le, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich Jan 2006

#### Distributed Generation Control Using Protection Principles, An D. T Le, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich

##### Faculty of Engineering and Information Sciences - Papers: Part A

No abstract provided.

Distributed Generation Diversity Level For Optimal Investment Planning, An D. T Le, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich Jan 2006

#### Distributed Generation Diversity Level For Optimal Investment Planning, An D. T Le, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich

##### Faculty of Engineering and Information Sciences - Papers: Part A

The task of improving the supply quality and maintaining supply continuity during emergencies has become more feasible for a distribution company (DISCO), owing to new developments in Distributed Generation (DG) technologies. Even though the technical issues regarding DG interconnection to the main grid are of great importance and are being addressed by on-going research, it must be clearly placed in the context of on the financial performance of the utility. In this paper, a general approach to quantify the technical benefits of DG employment is proposed. The power system economic impact is assessed by evaluating supply quality, supply reliability, system …

Control Stabilisation Of An Islanded System With Dfig Wind Turbine, M Aktarujjaman, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich Jan 2006

#### Control Stabilisation Of An Islanded System With Dfig Wind Turbine, M Aktarujjaman, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich

##### Faculty of Engineering and Information Sciences - Papers: Part A

Distributed Generation (DG) is often used to export power to the utility system. Loss of main supply can cause a severe loading mismatch between DG generation and load consumption. Consequently, the voltage and frequency of the islanded system will cross the allowable limit. Due to this fact, it is essential to control the voltage and frequency in the islanding mode of operation. In this paper, control stabilisation of an islanded system with a doubly-fed induction generator (DFIG) wind turbine has been addressed. Wind DG produces variable output and is not capable to produce enough reactive power. Hence, it is imperative …

Energy Storage System For Reduction Of Mid-Line Voltage Variation Of A Dfig Wnd Turbine Connected To A Weak Grid, M Aktarujjaman, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich Jan 2006

#### Energy Storage System For Reduction Of Mid-Line Voltage Variation Of A Dfig Wnd Turbine Connected To A Weak Grid, M Aktarujjaman, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich

##### Faculty of Engineering and Information Sciences - Papers: Part A

Penetration of wind power into electricity system is constantly increasing. Wind resources are usually distant from existing transmission lines. Wind farms are often connected to weak grids far from central generation stations. Maximum wind power extraction causes the more irregular and unpredicted power output of wind turbine, which has same nature as wind speed variation. The voltage in such long line is vulnerable with the consumption and generation imbalance. In a long line, the mid-line voltage is largely affected by the variation and the penetration of the wind fluctuating power. Fluctuating nature of wind power output and long transmission line …

Hydro-Turbine Governor Control: Theory, Techniques And Limitations, J Culberg, Michael Negnevitsky, Kashem M. Muttaqi Jan 2006

#### Hydro-Turbine Governor Control: Theory, Techniques And Limitations, J Culberg, Michael Negnevitsky, Kashem M. Muttaqi

##### Faculty of Engineering and Information Sciences - Papers: Part A

With the entry of Tasmania into the national electricity market, equipment upgrades are required in many parts of the existing power system. This presents an opportunity to embrace new technology, in order to enhance the current efficiency and productivity of the system. One area is that of hydro-turbine speed governors, an integral part of maintaining the frequency of the output. This paper analyses the current standard control algorithm for turbine governors, the PID controller. It illustrates the processes involved, tuning and their limitations. Finally, alternative control systems are discussed.

Black Start With Dfig Based Distributed Generation After Major Emergencies, M Aktarujjaman, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich Jan 2006

#### Black Start With Dfig Based Distributed Generation After Major Emergencies, M Aktarujjaman, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich

##### Faculty of Engineering and Information Sciences - Papers: Part A

Grid connected distributed generation (DG) increases reliability and additional benefits for consumers as well as utilities. The stable and reliable operation of a power system is necessary after major emergencies (or blackouts) following a major system event. Distributed generation may be capable of black start and contribute to fast restoration process at medium to low voltage level. A large scale voltage and frequency excursions may occur during the process of black start with distributed generation due to low inertia and intermittency in power generation. Energy storage integrated with DG can absorb initial impact of central generation and ensure smooth load …

Control Strategy Of Distributed Generation For Voltage Support In Distribution Systems, An D. T Le, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich Jan 2006

#### Control Strategy Of Distributed Generation For Voltage Support In Distribution Systems, An D. T Le, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich

##### Faculty of Engineering and Information Sciences - Papers: Part A

Voltage problem is always a critical issue in operating a distribution system. The uncertainties of load distribution and variation have introduced a great complexity to the task of maintaining system voltage within the permitted range. In this paper, small-scale generator, known as distributed generation (DG), is employed in the system and acting as a voltage regulator. The output of DG is controlled in such a way that acceptable level of electrical supply quality is achieved with a reasonable operating cost. The DG controller is tested with a non-uniformly varying load on the time domain basis. Simulations have been conducted with …

Loading Capabilities Assesment Of Power Transmission Lines, P Hu, Michael Negnevitsky, Kashem M. Muttaqi Jan 2006

#### Loading Capabilities Assesment Of Power Transmission Lines, P Hu, Michael Negnevitsky, Kashem M. Muttaqi

##### Faculty of Engineering and Information Sciences - Papers: Part A

This paper reviews the factors that affect the loading capabilities of the transmission line over the short duration. The paper demonstrates how to determine the impact of various parameters on the permissible loading of bare conductors of a power transmission line. Methods for calculating these factors are presented. A sample of a practical application is also included in order to show how these factors affect the loading capabilities of a transmission line.

Distributed Generation For Minimization Of Power Losses In Distribution Systems, Kashem M. Muttaqi, An D. T Le, Michael Negnevitsky, Gerard Ledwich Jan 2006

#### Distributed Generation For Minimization Of Power Losses In Distribution Systems, Kashem M. Muttaqi, An D. T Le, Michael Negnevitsky, Gerard Ledwich

##### Faculty of Engineering and Information Sciences - Papers: Part A

Appropriate size and location of distributed generation (DG) play a significant role in minimizing power losses in distribution systems. This paper represents techniques to minimize power losses in a distribution feeder by optimizing DG model in terms of size, location and operating point of DG. Sensitivity analysis for power losses in terms of DG size and DG operating point has been performed. The proposed sensitivity indices can indicate the changes in power losses with respect to DG current injection. The proposed techniques have been developed with considering load characteristics and representing loads with constant impedance and constant current models, separately. …

Spatial Prediction For Massive Datasets, Noel A. Cressie, Gardar Johannesson Jan 2006

#### Spatial Prediction For Massive Datasets, Noel A. Cressie, Gardar Johannesson

##### Faculty of Engineering and Information Sciences - Papers: Part A

Remotely sensed spatio-temporal datasets on the order of megabytes to terrabytes are becoming more common. For example, polar-orbiting satellites observe Earth from space, monitoring the Earth's atmospheric, oceanic, and terrestrial processes, and generate massive amounts of environmental data. The current generation of satellites, such as the National Aeronautic and Space Administration's (NASA) Earth Observing System (EOS) Terra and Aqua satellites, generate about 1.5 terrabytes of data per day. In the USA, there are remote-sensing projects in preparation that will dwarf even these datasets. NASA, the National Oceanic and Atmospheric Administration (NOAA), and the Department of Defense (DoD) have created the …

Generic Construction Of Hybrid Public Key Traitor Tracing With Full-Public-Traceability, Duong Hieu Phan, Rei Safavi-Naini, Joseph Tonien Jan 2006

#### Generic Construction Of Hybrid Public Key Traitor Tracing With Full-Public-Traceability, Duong Hieu Phan, Rei Safavi-Naini, Joseph Tonien

##### Faculty of Engineering and Information Sciences - Papers: Part A

No abstract provided.

An Efficient Single-Key Pirates Tracing Scheme Using Cover-Free Families, Joseph Tonien, Rei Safavi-Naini Jan 2006

#### An Efficient Single-Key Pirates Tracing Scheme Using Cover-Free Families, Joseph Tonien, Rei Safavi-Naini

##### Faculty of Engineering and Information Sciences - Papers: Part A

A cover-free family is a well-studied combinatorial structure that has many applications in computer science and cryptography. In this paper, we propose a new public key traitor tracing scheme based on cover-free families. The new traitor tracing scheme is similar to the Boneh-Franklin scheme except that in the Boneh-Franklin scheme, decryption keys are derived from Reed-Solomon codes while in our case they are derived from a cover-free family. This results in much simpler and faster tracing algorithms for single-key pirate decoders, compared to the tracing algorithms of Boneh-Franklin scheme that use Berlekamp- Welch algorithm. Our tracing algorithms never accuse innocent …

Human Visual Perception Of Region Warping Distortions With Different Display And Scene Characteristics, Yang-Wai Chow, Ronald Pose, Matthew Regan, James Phillips Jan 2006

#### Human Visual Perception Of Region Warping Distortions With Different Display And Scene Characteristics, Yang-Wai Chow, Ronald Pose, Matthew Regan, James Phillips

##### Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents human visual perception experiment results for a computer graphics rendering technique introduced in ACSC'05. In order to achieve a good immersive virtual reality experience, it is necessary to have at least 60 frames per second to ensure smooth motion. It is also necessary to have low end-to-end latency so that user interaction does not suffer from perceptible delays in images presented to the eyes. The Address Recalculation Pipeline (ARP) architecture reduces end-to-end latency in immersive Head Mounted Display (HMD) virtual reality systems. By using the ARP in conjunction with priority rendering, different sections of the scene are …

An Agent-Oriented Approach To Change Propagation In Software Evolution, Khanh Hoa Dam, Michael Winikoff, Lin Padgham Jan 2006

#### An Agent-Oriented Approach To Change Propagation In Software Evolution, Khanh Hoa Dam, Michael Winikoff, Lin Padgham

##### Faculty of Engineering and Information Sciences - Papers: Part A

Software maintenance and evolution are inevitable activities since almost all software that is useful and successful stimulates user-generated requests for change and improvements. One of the most critical problems in software maintenance and evolution is to maintain consistency between software artefacts by propagating changes correctly. Although many approaches have been proposed, automated change propagation is still a significant technical challenge in software engineering. In this paper we present a novel, agent-oriented approach to deal with change propagation in evolving software systems that are developed using the Prometheus methodology. A metamodel with a set of the Object Constraint Language (OCL) rules …

Flexural Behaviour Of Hybrid Frp-Concrete-Steel Double Skin Tubular Members, T Yu, Y L. Wong, J G. Teng, S L. Dong, E S.S Lam Jan 2006

#### Flexural Behaviour Of Hybrid Frp-Concrete-Steel Double Skin Tubular Members, T Yu, Y L. Wong, J G. Teng, S L. Dong, E S.S Lam

##### Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents the results of an experimental study on the flexural behavior of a new type of hybrid FRP-concrete-steel member as well as results from a corresponding theoretical model based on the plane section assumption and the fiber element approach. This new type of hybrid member is in the form of a double-skin tube, composed of a steel inner tube and an FRP outer tube with a concrete infill between the two tubes, and may be employed as columns or beams. The parameters examined in this study include the section configuration, the concrete strength, and the thicknesses of the …

An Analytic Approach To Spectral Flow In Von Neumann Algebras, M-T Benameur, Alan L. Carey, John Phillips, Adam C. Rennie, Fyodor A. Sukochev, K P. Wojciechowski Jan 2006

#### An Analytic Approach To Spectral Flow In Von Neumann Algebras, M-T Benameur, Alan L. Carey, John Phillips, Adam C. Rennie, Fyodor A. Sukochev, K P. Wojciechowski

##### Faculty of Engineering and Information Sciences - Papers: Part A

The analytic approach to spectral flow is about ten years old. In that time it has evolved to cover an ever wider range of examples. The most critical extension was to replace Fredholm operators in the classical sense by Breuer-Fredholm operators in a semifinite von Neumann algebra. The latter have continuous spectrum so that the notion of spectral flow turns out to be rather more difficult to deal with. However quite remarkably there is a uniform approach in which the proofs do not depend on discreteness of the spectrum of the operators in question. The first part of this paper …

Network Measures And Simulation For Knowledge Intensive Work Performance, Kon Shing Kenneth Chung, Liaquat Hossain, Joseph Davis Jan 2006

#### Network Measures And Simulation For Knowledge Intensive Work Performance, Kon Shing Kenneth Chung, Liaquat Hossain, Joseph Davis

##### Faculty of Engineering and Information Sciences - Papers: Part A

We describe the process of designing a reliable and valid instrument for collecting network and attribute data. Here, we explore the relationship between social networks structure, information and communication technologies (ICT) use and attitude towards performance in knowledge intensive work. We first develop a model for exploring the inherent relationship between the three concepts based on existing literature. We then develop appropriate item sets for measuring different independent (network structure, ICT use) and dependent variables (performance). We use the reliable item sets along with justifications to construct different phases of our instrument. In doing so, we introduce a simulation approach …

Using Rfid And Bluetooth For Localised Interaction With Wireless Embedded Internet Devices, Matthew D'Souza, Montserrat Ros, Adam Postula Jan 2006

#### Using Rfid And Bluetooth For Localised Interaction With Wireless Embedded Internet Devices, Matthew D'Souza, Montserrat Ros, Adam Postula

##### Faculty of Engineering and Information Sciences - Papers: Part A

Interaction with embedded devices can take on many forms. This paper describes the implementation of an interactive information network and intuitive mechanisms for the personal or home environment using Bluetooth wireless communication and Radio Frequency ID (RFID) tag technology. This approach combines the freedom associated with wireless communication and the ability to detect user commands by RFID location information. Embedded Access Points are described along with intuitive mechanisms including digital pen/paper, interactive information board and mobile computing devices. Specifically, the web access point facilitated an Internet over Bluetooth link and was found to provide an average data rate of 15.97kbps. …

Specifying System Requirements Using The 5s Method, Robert B. K Brown, Peter Hyland, Ian C. Piper Jan 2006

#### Specifying System Requirements Using The 5s Method, Robert B. K Brown, Peter Hyland, Ian C. Piper

##### Faculty of Engineering and Information Sciences - Papers: Part A

The 5S Method takes an Activity Theory approach to stakeholder elicitation. We interview stakeholders and build up a network of Activities according to Activity Theory precepts. These Activities are hierarchically decomposed into the smaller units of Action and Operation. This comprises a useful conceptual map of the human motivations and dependencies prior to insertion of the new computer based system. To identify and describe such a potential computer system, we analyse and identify linkages between the Activities and assemble a list of those which could usefully pass through such a computer system. Design decisions are driven and evaluated by reference …

Experience In The Application Of Iec/Tr 61000-3-6 To Harmonic Allocation In Transmission Systems, T J. Browne, V J. Gosbell, S Perera, D A. Robinson, L M. Falla, P J. Windle, A C. D Perera Jan 2006

#### Experience In The Application Of Iec/Tr 61000-3-6 To Harmonic Allocation In Transmission Systems, T J. Browne, V J. Gosbell, S Perera, D A. Robinson, L M. Falla, P J. Windle, A C. D Perera

##### Faculty of Engineering and Information Sciences - Papers: Part A

Technical report IEC/TR 61000-3-6 is widely used as a guide to harmonic management in HV and MV networks, assisting in coordination of harmonic levels between utility and customer. In 2001, Australia and New Zealand adopted the harmonic standard AS/NZS 61000.3.6, which closely follows the above IEC technical report. As a result, transmission utilities and connected loads are required by government regulations to abide by the harmonic allocations set by the standard. The technical report contains some useful general principles which can be applied to the harmonic management of power systems. However, unexpected difficulties can be found when attempts are made …