Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Distributed (6)
- Geant4 (6)
- Generation (5)
- Control (4)
- Models (4)
-
- Approach (3)
- Dfig (3)
- Simulation (3)
- System (3)
- Systems (3)
- Turbine (3)
- Algebras (2)
- Analysis (2)
- Construction (2)
- Distribution (2)
- Flow (2)
- Human (2)
- Hybrid (2)
- Key (2)
- Planning (2)
- Power (2)
- Propagation (2)
- Radiation (2)
- Regional (2)
- Rolling (2)
- Theory (2)
- Tracing (2)
- Transmission (2)
- Validation (2)
- Voltage (2)
Articles 1 - 30 of 46
Full-Text Articles in Engineering
Quantifying The Regional Load-Bearing Ability Of Trans-Tibial Stumps, Ming Zhang, Winson Lee
Quantifying The Regional Load-Bearing Ability Of Trans-Tibial Stumps, Ming Zhang, Winson Lee
Faculty of Engineering and Information Sciences - Papers: Part A
This paper reports findings of experiments aiming to (1) compare the load tolerant ability over different regions of stumps of lower limb amputees, (2) study the effect of walking on the load tolerant ability, and (3) examine the distal-end weight-bearing ability supported by different interface materials. The method was to apply increasing load to the stump up to the pain level through a force transducer or a digital scale, considering the effect of regional difference, walking, and interface materials. The results show that the patellar tendon and the distal end of the fibula were the best and worst load-tolerant region, …
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
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 …
Distributed Generation Diversity Level For Optimal Investment Planning, An D. T Le, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich
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 …
Distributed Generation Control Using Protection Principles, An D. T Le, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich
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.
Control Strategy Of Distributed Generation For Voltage Support In Distribution Systems, An D. T Le, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich
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 …
Geant4 Simulation For Lhc Radiation Monitoring, M Glaser, S Guatelli, B Mascialino, M Moll, M G. Pia, F Ravotti
Geant4 Simulation For Lhc Radiation Monitoring, M Glaser, S Guatelli, B Mascialino, M Moll, M G. Pia, F Ravotti
Faculty of Engineering and Information Sciences - Papers: Part A
Monitoring radiation background is a crucial task for the operation of LHC experiments. A project is in progress at CERN for the optimisation of the radiation monitors for LHC experiments. A simulation system based on Geant4, designed to assist the engineering optimisation of LHC radiation monitor detectors, is presented. Various detector packaging configurations are studied through their Geant4-based simulation, and their behaviour is compared.
The Use Of Maple Platform For The Study Of Geodisc Motion On Curved Spacetimes, Dumitru N. Vulcanov, Valentina D. Wheeler
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.
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
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
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
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 …
The Effect Of Small Business Clusters In Prioritising Barriers To E-Commerce Adoption In Regional Smes, Robert Macgregor, Lejla Vrazalic
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 …
Geant4 Antropomorphic Phantoms, Susanna Guatelli, Barbara Mascialino, Maria Grazia Pia, Witold Pokorski
Geant4 Antropomorphic Phantoms, Susanna Guatelli, Barbara Mascialino, Maria Grazia Pia, Witold Pokorski
Faculty of Engineering and Information Sciences - Papers: Part A
A novel architectural approach to the design of human phantom software models is presented. A detailed design has been developed to enable the adoption of this approach in Geant4-based simulation applications. A few preliminary implementations and application demonstrations are described.
Geant4 Simulation In A Distributed Computing Environment, Susanna Guatelli, Alfonso Mantero, Patricia Mendez Lorenzo, Jakub Moscicki, Maria Grazia Pia
Geant4 Simulation In A Distributed Computing Environment, Susanna Guatelli, Alfonso Mantero, Patricia Mendez Lorenzo, Jakub Moscicki, Maria Grazia Pia
Faculty of Engineering and Information Sciences - Papers: Part A
A general system to perform a Geant4-based simulation in a distributed computing environment is presented. The architecture developed makes the system transparent to sequential or parallel execution and to the environment where the simulation is run: a single machine, a local cluster or a geographically distributed grid.
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
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 …
Hydro-Turbine Governor Control: Theory, Techniques And Limitations, J Culberg, Michael Negnevitsky, Kashem M. Muttaqi
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.
A Numerical Approach To Evaluate The Fatigue Life Of Monolimb, Nian-Zhong Chen, Winson Lee, Ming Zhang
A Numerical Approach To Evaluate The Fatigue Life Of Monolimb, Nian-Zhong Chen, Winson Lee, Ming Zhang
Faculty of Engineering and Information Sciences - Papers: Part A
Monolimb refers to a transtibial prosthesis with the prosthetic socket and the shank being molded into one piece of thermoplastic material. Shank flexibility of a monolimb can improve gait and comfort. However, fatigue failure of monolimbs under cyclic walking load is an important concern. This study is to evaluate the fatigue life of a monolimb designed for a transtibial amputee, based on finite element analysis, the statistical Miner's rule and reliability analysis. Stress uncertainty due to modeling error and the scatter in fatigue test data were considered. Results indicated that the accuracy of fatigue life evaluation of monolimb depends significantly …
A Robust Design Procedure For Improvement Of Quality Of Lower-Limb Prosthesis, Nian-Zhong Chen, Winson Lee, Ming Zhang
A Robust Design Procedure For Improvement Of Quality Of Lower-Limb Prosthesis, Nian-Zhong Chen, Winson Lee, Ming Zhang
Faculty of Engineering and Information Sciences - Papers: Part A
Lower-limb prostheses are used to restore amputee's walking. Monolimb is one of the designs referring to socket and the shank being molded into one piece of thermoplastic material. Appropriate shank flexibility of a monolimb can improve gait of an amputee. However, during the fabrication, the variations of design variables are inevitably produced which may lead the unexpected shank deflection and directly influence on gait efficiency of an amputee. This paper presents a robust design procedure for improvement of quality of the monolimb by simultaneously minimizing performance variations caused by variations in design variables and bringing the mean value of performance …
An Agent-Oriented Approach To Change Propagation In Software Evolution, Khanh Hoa Dam, Michael Winikoff, Lin Padgham
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 …
Using Rfid And Bluetooth For Localised Interaction With Wireless Embedded Internet Devices, Matthew D'Souza, Montserrat Ros, Adam Postula
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. …
Direction-Of-Arrival Estimation In The Presence Of Unknown Nonuniform Noise Fields, Yuntao Wu, Chaohuan Hou, Guisheng Liao, Qinghua Guo
Direction-Of-Arrival Estimation In The Presence Of Unknown Nonuniform Noise Fields, Yuntao Wu, Chaohuan Hou, Guisheng Liao, Qinghua Guo
Faculty of Engineering and Information Sciences - Papers: Part A
A new method for estimating directions-of-arrival (DOA) of multiple spatial narrowband signals in the presence of spatially nonuniform independent sensor noise with unknown covariance is presented. An estimate of the colored noise-covariance matrix is given first. The received data for parameter estimation is then prewhitened using the estimated noise covariance, hence, overcoming the highly biased estimates. Furthermore, the performance improvement of standard MUSIC method is confirmed by computer simulations. © 2006 IEEE.
Behavior Of Transversal Crack On Slab Corner During V-H Rolling Process, Hai-Liang Yu, Xiang-Hua Liu, Chang-Sheng Li, Y Kusaba
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 …
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
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
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 …
Specifying System Requirements Using The 5s Method, Robert B. K Brown, Peter Hyland, Ian C. Piper
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 …
Comparison Of Channelized Hotelling And Human Observers In Determining Optimum Os-Em Reconstruction Parameters For Myocardial Spect, Karen L. Gilland, Benjamin M. W Tsui, Yujin Qi, Grant T. Gullberg
Comparison Of Channelized Hotelling And Human Observers In Determining Optimum Os-Em Reconstruction Parameters For Myocardial Spect, Karen L. Gilland, Benjamin M. W Tsui, Yujin Qi, Grant T. Gullberg
Faculty of Engineering and Information Sciences - Papers: Part A
The performance of the Channelized Hotelling Observer (CHO) was compared to that of human observers for determining optimum parameters for the iterative OS-EM image reconstruction method for the task of defect detection in myocardial SPECT images. The optimum parameters were those that maximized defect detectability in the SPECT images. Low noise, parallel SPECT projection data, with and without an anterior, inferior or lateral LV wall defect, were simulated using the Monte Carlo method. Poisson noise was added to generate noisy realizations. Data were reconstructed using OS-EM at 1 & 4 subsets/iteration and at 1, 3, 5, 7 & 9 iterations. …
Gaussian Message Passing On Linear Models: An Update, Hans-Andrea Loeliger, Junli Hu, Sascha Korl, Qinghua Guo, Li Ping
Gaussian Message Passing On Linear Models: An Update, Hans-Andrea Loeliger, Junli Hu, Sascha Korl, Qinghua Guo, Li Ping
Faculty of Engineering and Information Sciences - Papers: Part A
This semi-tutorial paper considers message passing algorithms on factor graphs of linear Gaussian models. Freshly polished tables of message computation rules are given and their use is demonstrated for soft-in soft-out equalization.
Generic Construction Of Hybrid Public Key Traitor Tracing With Full-Public-Traceability, Duong Hieu Phan, Rei Safavi-Naini, Joseph Tonien
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
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 …
Control Stabilisation Of An Islanded System With Dfig Wind Turbine, M Aktarujjaman, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich
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 …
Black Start With Dfig Based Distributed Generation After Major Emergencies, M Aktarujjaman, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich
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 …