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Full-Text Articles in Physical Sciences and Mathematics
Grounding Locations Assessment Of Practical Power System, Nadheer Shalash, Ahmed M. Haidar, Abdul Sattar
Grounding Locations Assessment Of Practical Power System, Nadheer Shalash, Ahmed M. Haidar, Abdul Sattar
Faculty of Informatics - Papers (Archive)
Grounding Points (GPs) are installed in electrical power system to drive protective devices and accomplish the person- nel safety. The general grounding problem is to find the optimal locations of these points so that the security and reli- ability of power system can be improved. This paper presents a practical approach to find the optimal location of GPs based on the ratios of zero sequence reactance with positive sequence reactance (X0/X1), zero sequence resistance with positive sequence reactance (R0/X1) and Ground Fault Factor (GFF). The optimal values of these indicators were deter- mined by considering several scenarios of fault disturbances …
Transport Commons: A Community Based Public Transport System, Farzad Safaei
Transport Commons: A Community Based Public Transport System, Farzad Safaei
Faculty of Informatics - Papers (Archive)
In this paper we present a generalization of the concept of car-pooling for a public transport system, in which members of the community donate their trips to the 'transport commons'. The proposed system will then match the passengers to vehicles based on a range of criteria, including trip times, personal choices and economic incentives. We develop an analytical model to determine the probability of obtaining a ride from the transport commons in a worst-case scenario. The results of the analysis as well as simulation study demonstrate that the transport commons can provide a practical basis for a dependable public transport …
An Analysis Of An Activated Sludge Process Containing A Sludge Disintegration System, Mark I. Nelson, Easwaran Balakrishnan
An Analysis Of An Activated Sludge Process Containing A Sludge Disintegration System, Mark I. Nelson, Easwaran Balakrishnan
Faculty of Informatics - Papers (Archive)
A continuous flow bioreactor is a well-stirred vessel containing microorganisms (X) through which a substrate (S) flows at a continuous rate. The microorganisms grow through the consumption of the substrate, producing more microorganisms and products. The products will typically contain carbon dioxide, nitrogen, water and other species, including biological compounds, specific to the process under consideration. The nature of these products is unimportant in this study. Unused substrate, microorganisms, and products flow out of the reactor. The use of a continuous flow bioreactor to treat sewage or industrial wastewaters is known as the activated sludge process. One drawback associated with …
Development Of A Peer-To-Peer Information Sharing System Using Ontologies, Ghassan Beydoun, Graham Low, Numi Tran, Paul Bogg
Development Of A Peer-To-Peer Information Sharing System Using Ontologies, Ghassan Beydoun, Graham Low, Numi Tran, Paul Bogg
Faculty of Informatics - Papers (Archive)
Most existing agent-oriented methodologies ignore system extensibility, interoperability and reusability issues. Ontologies have been found to play a significant role in facilitating interoperability, reusability, MAS development activities (including MAS analysis and agent knowledge modeling) and MAS run-time operation (including agent communication and reasoning). However, most of the existing AOSE methodologies do not provide support for ontology-based MAS development. We present software engineering requirements for ontology-based development for MAS and examine an existing methodology, MOBMAS - a "Methodology for Ontology-Based MASs", which makes use of ontologies as a modeling tool. In this examination, we highlight how MOBMAS can be extended to …
Understanding The Conducting States Of Active And Passive Switches In An Inverter Circuit Used For Power System Applications, Danny Sutanto, B.P. Divakar, K.W.E. Cheng
Understanding The Conducting States Of Active And Passive Switches In An Inverter Circuit Used For Power System Applications, Danny Sutanto, B.P. Divakar, K.W.E. Cheng
Faculty of Informatics - Papers (Archive)
Bi-directional inverter circuits are commonly used in many applications in power systems, such as in FACTS devices, energy storage systems and active power filters. Many power engineering students however find it difficult to understand the conducting states of the active switches (transistors, IGBTs) and the passive switches (the antiparallel diodes connected across the active switches). It seems a mystery to them that power can flow from a lower voltage ac system to a higher voltage dc system to charge the energy storage system. This paper proposes a simple chart that intuitively explains how to determine the states (either conducting or …
An Assessment Tool For E-Government System Performance: A Citizen-Centric Model, Shatha A. Al-Haddad, Peter Hyland, Geoffrey Hubona
An Assessment Tool For E-Government System Performance: A Citizen-Centric Model, Shatha A. Al-Haddad, Peter Hyland, Geoffrey Hubona
Faculty of Informatics - Papers (Archive)
Governments worldwide have, increasingly, implemented e-government initiatives for their potential significant benefits; among which, delivering better services to citizens through increasing citizens' convenience, satisfaction, and independence; and saving their time, effort, and cost. Achieving each benefit is an objective to these governments and fulfilling each objective is considered a critical success factors. Hence, governments need to assess the extent to which they were able to obtain their preset goals. This study merely focuses on the citizens' perspective of the evaluation. However, the literature seems to lack studies that propose such a sufficient evaluation tool that has been reliably validated. Therefore, …
Coordinated Utilisation Of Wind Farm Reactive Power Capability For System Loss Optimisation, Lasantha Meegahapola, S Durairaj, D Flynn, B Fox
Coordinated Utilisation Of Wind Farm Reactive Power Capability For System Loss Optimisation, Lasantha Meegahapola, S Durairaj, D Flynn, B Fox
Faculty of Informatics - Papers (Archive)
Most wind farms currently being installed are based upon doubly fed induction generator (DFIG) or direct-drive synchronous generator (DDSG) technology. Given that one of the impacts of introducing distributed generation is an alteration of steady-state power flows and voltages, both technologies are capable of providing local voltage support. Wind farms may, therefore, be included in optimal power flow (OPF) calculations to minimise fuel cost and/or network losses. The IEEE 30-bus system is considered as a case study, comparing fixed-speed induction generator (FSIG) requirements with DFIG capability. Results are presented for a range of DFIG capability modes, at varying system load …
Design An Automatic Appointment System To Improve Patient Access To Primary Health Care, Hongxiang Hu, Ping Yu, Jun Yan
Design An Automatic Appointment System To Improve Patient Access To Primary Health Care, Hongxiang Hu, Ping Yu, Jun Yan
Faculty of Informatics - Papers (Archive)
Advanced Access model has been introduced in general practice in the United States to improve patient access to primary health care services for more than ten years. It has brought in the benefits of eliminating service provider’s waiting lists, improving patients’ timely access to services and reducing no-show rate. However, to implement this model, practices need to collect relevant information, develop contingency plans and set up practice strategies to balance the provision of care and patient’s demand. These tasks are not always easy to achieve. Understanding the requirements and constraints for effective management of patient booking is essential for developing …
Building A System For Managing Clinical Pathways Using Digital Pens, Linda L. Dawson, Virginia Plummer, Stephen Weeding, Terri Harlem, Bob Ribbons, David Waterhouse
Building A System For Managing Clinical Pathways Using Digital Pens, Linda L. Dawson, Virginia Plummer, Stephen Weeding, Terri Harlem, Bob Ribbons, David Waterhouse
Faculty of Informatics - Papers (Archive)
Background: A research team from Monash University and Peninsula Health, Victoria is undertaking a trial of digital pen and paper technology for clinical pathway management. Digital pen and paper allows for the capture of images of handwritten documents using an embedded camera in the pen which is matched with special patterns of dots on the paper. These digitised images can be uploaded to a database for analysis. Objectives: Clinical pathways have been adopted in most Australian hospitals to document and manage multidisciplinary care across a variety of acute care environments. Analysis of the information collected in paper-based clinical pathway documents …
An Estimation Method For Feedback Level Factor C Of A Self-Mixing Interferometry System, Yuanlong Fan, Yanguang Yu, Jiangtao Xi, Joe F. Chicharo
An Estimation Method For Feedback Level Factor C Of A Self-Mixing Interferometry System, Yuanlong Fan, Yanguang Yu, Jiangtao Xi, Joe F. Chicharo
Faculty of Informatics - Papers (Archive)
This paper presents a fast estimation method for feedback level factor C of a self-mixing interferometry (SMI) system. The reconstruction of a displacement waveform using a SMI signal needs to know a C value. However, it is difficult to maintain a constant C value during the reconstruction process. We study the features of the reconstructed displacement waveforms incorporating different pre-set C values and classify waveforms into two types. Bisection method is introduced in our method for fast estimating C value. The effectiveness of our proposed method has been verified by both simulation and experimental data.
Fpga-Based Signal Processing In An Optical Feedback Self-Mixing Interferometry System, Zongzhen Li, Yanguang Yu, Jiangtao Xi, Huiying Ye
Fpga-Based Signal Processing In An Optical Feedback Self-Mixing Interferometry System, Zongzhen Li, Yanguang Yu, Jiangtao Xi, Huiying Ye
Faculty of Informatics - Papers (Archive)
Optical feedback Self-mixing Interferometry (OFSMI) can achieve a high-resolution displacement sensing and measurement by using advanced digital signal processing. However, most existing signal processing algorithms used for OFSMI signals are implemented on a PC by Matlab or other programming languages. In this case, the whole structure of OFSMI sensing system is incompact and the measurement is in low speed. The design trends in sensing systems are towarding to small size, high integration and fast real time processing. These trends require us to improve the existing OFSMI design. It is a good solution to apply Field-programmable gate arrays (FPGAs) technique onto …
Optimisation Of Component Sizes For A Hybrid Remote Area Power Supply System, Saad M. Sayeef, Nishad Mendis, Kashem Muttaqi
Optimisation Of Component Sizes For A Hybrid Remote Area Power Supply System, Saad M. Sayeef, Nishad Mendis, Kashem Muttaqi
Faculty of Informatics - Papers (Archive)
In this paper, an optimisation model for determination of the optimal sizes of various system components, including wind, diesel and energy storage, has been developed to obtain a reliable and cost-effective wind-diesel hybrid remote area power supply (RAPS) system. A linear programming based cost minimisation algorithm has been formulated for determination of optimal sizes of various components in a RAPS system with consideration of continually varying wind and system load. The system constraints, including power balance for both under-generation and over-generation scenarios, have been considered in the optimisation formulation. Optimisation model to minimize the total cost of the system based …
Support Of Distribution System Using Distributed Wind And Pv Systems, Kai Zou, Ashish P. Agalgaonkar, Kashem Muttaqi, Sarath Perera, N Browne
Support Of Distribution System Using Distributed Wind And Pv Systems, Kai Zou, Ashish P. Agalgaonkar, Kashem Muttaqi, Sarath Perera, N Browne
Faculty of Informatics - Papers (Archive)
The application of renewable distributed generation (DG) could be considered as an alternative approach for distribution system expansion planning not only to reduce power loss and carbon emission, but also to improve system voltage profile. This paper investigates technical aspects relatedto voltage support and loss reduction in distribution systems with distributed wind and solar generation. The probabilistic wind, solar, and load models have been developed in order to address uncertain nature of wind speed, solar radiation, and load demand. Investigations have been carried out using Monte Carlo based probabilistic load flow analysis to estimate the probability distributions of system state …
Voltage Quality Behaviour Of A Wind Turbine Based Remote Area Power System, Nishad Mendis, Kashem Muttaqi, Sarath Perera
Voltage Quality Behaviour Of A Wind Turbine Based Remote Area Power System, Nishad Mendis, Kashem Muttaqi, Sarath Perera
Faculty of Informatics - Papers (Archive)
The power quality behaviour of a Remote Area Power System (RAPS) consisting of a Doubly Fed Induction Generator (DFIG), its main loads and a dummy load is presented in this paper. The dummy load is used to maintain the power balance of the system under changing wind and loading conditions. The performance of the remote area power system subject to various loading conditions has been evaluated in terms of the voltage quality, an aspect which has not received much attention in the past. The existing Distributed Generation (DG) power quality standards are taken as the basis to compare the voltage …
Dynamic Modelling Of Hydroelectric Turbine-Generator Unit Connected To A Hvdc System For Small Signal Stability Analysis, Yin Chin Choo, Ashish P. Agalgaonkar, Kashem Muttaqi, Sarath Perera, Michael Negnevitsky
Dynamic Modelling Of Hydroelectric Turbine-Generator Unit Connected To A Hvdc System For Small Signal Stability Analysis, Yin Chin Choo, Ashish P. Agalgaonkar, Kashem Muttaqi, Sarath Perera, Michael Negnevitsky
Faculty of Informatics - Papers (Archive)
This paper presents the linearised small-signal dynamic modelling of hydroelectric turbine-generator (TG) unit with CIGRE first high-voltage direct current (HVDC) benchmark system in the synchronously rotating D-Q reference frame for small-signal stability analysis. The interaction behaviour between the hydroelectric unit and the dynamics and control of HVDC system is investigated utilising eigen-analysis,participation factor analysis and by conducting sensitivity studies. The computation of eigenvalues and eigenvectors for small signal stability analysis provides an invaluable insight onto the power system dynamic behaviour by characterising the damping and frequency of the system oscillatory modes. Theconsequences of different operating conditions, such as active and …
A Car Detection System Based On Hierarchical Visual Features, Fok Hing Chi Tivive, Abdesselam Bouzerdoum
A Car Detection System Based On Hierarchical Visual Features, Fok Hing Chi Tivive, Abdesselam Bouzerdoum
Faculty of Informatics - Papers (Archive)
In this paper, we address the problem of detecting and localizing cars in still images. The proposed car detection system is based on a hierarchical feature detector in which the processing units are shunting inhibitory neurons. To reduce the training time and complexity of the network, the shunting inhibitory neurons in the first layer are implemented as directional nonlinear filters, whereas the neurons in the second layer have trainable parameters. A multi-resolution processing scheme is implemented so as to detect cars of different sizes, and to reduce the number of false positives during the detection stage, an adaptive thresholding strategy …
Vulnerability Assessment Of Power System Using Radial Basis Function Neural Network And A New Feature Extraction Method, Ahmed M. Haidar, Azah Mohamed, Aini Hussain
Vulnerability Assessment Of Power System Using Radial Basis Function Neural Network And A New Feature Extraction Method, Ahmed M. Haidar, Azah Mohamed, Aini Hussain
Faculty of Informatics - Papers (Archive)
Vulnerability assessment in power systems is important so as to determine how vulnerable a power system in case of any unforeseen catastrophic events. This paper presents the application of Radial Basis Function Neural Network (RBFNN) for vulnerability assessment of power system incorporating a new proposed feature extraction method named as the Neural Network Weight Extraction (NNWE) for dimensionality reduction of input data. The performance of the RBFNN is compared with the Multi Layer Perceptron Neural Network (MLPNN) so as to evaluate the effectiveness of the RBFNN in assessing the vulnerability of a power system based on the indices, power system …
A Diagrammatic Reasoning System For The Description Logic Alc, Peter W. Eklund, Frithjof Dau
A Diagrammatic Reasoning System For The Description Logic Alc, Peter W. Eklund, Frithjof Dau
Faculty of Informatics - Papers (Archive)
Diagrammatic reasoning is a tradition of visual logic that allows sentences that are equivalent to first order logic to be written in a visual or structural form: usually for improved usability. A calculus for the diagram can then be defined that allows well-formed formulas to be derived. This calculus is intended in the analog of logical inference. Description logics (DLs) have become a popular knowledge representation and processing language. DLs correspond to decidable fragments of first order logic; their notation is in the style of symbolic, variable-free formulas. Moreover, DLs are equipped with table au theorem provers that are proven …
A Real-Time Facial Expression Recognition System For Online Games, Ce Zhan, Wanqing Li, Philip Ogunbona, Farzad Safaei
A Real-Time Facial Expression Recognition System For Online Games, Ce Zhan, Wanqing Li, Philip Ogunbona, Farzad Safaei
Faculty of Informatics - Papers (Archive)
Multiplayer online games (MOGs) have become increasingly popular because of the opportunity they provide for collaboration, communication, and interaction. However, compared with ordinary human communication, MOG still has several limitations, especially in communication using facial expressions. Although detailed facial animation has already been achieved in a number of MOGs, players have to use text commands to control the expressions of avatars. In this paper, we propose an automatic expression recognition system that can be integrated into an MOG to control the facial expressions of avatars. To meet the specific requirements of such a system, a number of algorithms are studied, …
Voltage Unbalance Emission Limits For Installations: General Guidelines And System Specific Considerations, Robert Koch, Alexander Baitch, Sarath Perera, Prabodha Paranavithana
Voltage Unbalance Emission Limits For Installations: General Guidelines And System Specific Considerations, Robert Koch, Alexander Baitch, Sarath Perera, Prabodha Paranavithana
Faculty of Informatics - Papers (Archive)
Guidelines for developing voltage unbalance emission limits for installations connected to EHV, HV, and MV power systems have recently been published as a technical report by the International Electrotechnical Commission (IEC). These guidelines, based on the work of Joint Working Group CIGRE/CIRED C4.103, are intended to provide a common basis for the development of similar guidelines or standards in specific countries. This paper reviews these international guidelines and the background to the development of specific recommendations made in the technical report. It also considers elements of these guidelines that may relate to specific network considerations, and therefore may be of …
Ontology-Based Knowledge Representation For A P2p Multi-Agent Distributed Intrusion Detection System, Dayong Ye, Quan Bai, Minjie Zhang
Ontology-Based Knowledge Representation For A P2p Multi-Agent Distributed Intrusion Detection System, Dayong Ye, Quan Bai, Minjie Zhang
Faculty of Informatics - Papers (Archive)
Many research efforts on application of ontology in network security have been done in the past decade. However, they mostly stop at initial proposal or focus on framework design without detailed representation of intrusion or attack and relevant detection knowledge with ontology. In this paper, the design and implementation of ontology-based knowledge representation for a peer-to-peer multi-agent distributed intrusion detection system (ontology-based MADIDS) are introduced. An example which demonstrates the representation of an attack with ontology and the relevant detection process is also presented. In ontology-Based MADIDS, ontology technique enables peers in the system and agents in one peer to …
Vulnerability Assessment Of A Large Sized Power System Considering A New Index Based On Power System Loss, Ahmed M. Haidar, Azah Mohamed, Aini Hussain
Vulnerability Assessment Of A Large Sized Power System Considering A New Index Based On Power System Loss, Ahmed M. Haidar, Azah Mohamed, Aini Hussain
Faculty of Informatics - Papers (Archive)
The concept of power system vulnerability assessment combines information on the level of system security as well as information on a wide range of situations, events and contingencies with regards to which a system is vulnerable. This paper attempts to investigate and evaluate the effect of line outage, generation outage and amount of load disconnected on the power transmission network losses of a large size power system. These effects will be investigated and evaluated using new proposed method based on vulnerability index of power system loss. The objectives of this work is to evaluate and compare the efficiency of the …
System Architecture And Mobility Management For Mobile Immersive Communications, Mehran Dowlatshahi, Farzad Safaei
System Architecture And Mobility Management For Mobile Immersive Communications, Mehran Dowlatshahi, Farzad Safaei
Faculty of Informatics - Papers (Archive)
We propose a system design for delivery of immersive communications to mobile wireless devices based on a distributed proxy model. It is demonstrated that this architecture addresses key technical challenges for the delivery of these services, that is, constraints on link capacity and power consumption in mobile devices. However, additional complexity is introduced with respect to application layer mobility management. The paper proposes three possible methods for updating proxy assignments in response to mobility management and compares the performance of these methods.
Rfid-Based Anti-Theft Auto Security System With An Immobilizer, Geeth Jayendra, Sisil Kumarawadu, Lasantha Meegahapola
Rfid-Based Anti-Theft Auto Security System With An Immobilizer, Geeth Jayendra, Sisil Kumarawadu, Lasantha Meegahapola
Faculty of Informatics - Papers (Archive)
This paper presents a novel radio frequency identification (RFID) based vehicle immobilizer system, which features low hacking probability while preserving the safety of the passengers of the hijacked vehicle. The immobilizer uses the active RFID technology where the tag is generated with comparatively large character sets. The receiving unit is intelligently integrated into three control circuits in the vehicle, namely, ignition circuit, power control unit, and automatic gear changing system, enabling it to bring the vehicle speed down to zero in a safe step by step manner. The anti-theft auto security system proposed here was tested under different weather conditions …
Application Of Semistructured Data Model To The Implementation Of Semantic Content-Based Video Retrieval System, Lilac A. E. Al-Safadi, Janusz R. Getta
Application Of Semistructured Data Model To The Implementation Of Semantic Content-Based Video Retrieval System, Lilac A. E. Al-Safadi, Janusz R. Getta
Faculty of Informatics - Papers (Archive)
Semantic indexing of a video document is a process that performs the identification of elementary and complex semantic units in the indexed document in order to create a semantic index defined as a mapping of semantic units into the sequences of video frames. Semantic content-based video retrieval system is a software system that uses a semantic index built over a collection of video documents to retrieve the sequences of video frames that satisfy the given conditions. This work introduces a new multilevel view of data for the semantic content-based video retrieval systems. At the topmost level, we define an abstract …
New Method Vulnerability Assessment Of Power System, Ahmed M. Haidar, Azah Mohamed, Aini Hussain
New Method Vulnerability Assessment Of Power System, Ahmed M. Haidar, Azah Mohamed, Aini Hussain
Faculty of Informatics - Papers (Archive)
Vulnerability assessment in power systems is to determine a power system`s ability to continue to provide service in case of an unforeseen catastrophic contingency. It combines information on the level of system security as well as information on a wide range of scenarios, events and contingencies. To assess the level of system strength or weakness relative to the occurrence of an undesired event, a quantitative measure based on vulnerability index is often considered. In this study, a new vulnerability assessment method is proposed based on total power system loss which considers power generation loss due to generation outage, power line …
A System For The 3d Reconstruction Of The Human Face Using The Structured Light Approach, Dean Mcguire, Prashan Premaratne
A System For The 3d Reconstruction Of The Human Face Using The Structured Light Approach, Dean Mcguire, Prashan Premaratne
Faculty of Informatics - Papers (Archive)
This paper will describe a computer vision system under development with the aim of use in robust facial recognition applications. The system employs the structured light approach to solve the correspondence problem. The system has been designed with ease of use in mind with calibration procedures designed to be simple enough to be carried out without the use of precision measuring equipment, but robust enough to provide good quality 3D reconstructions. The hardware in use is of consumer grade and is being used in an unmodified form. Early reconstructions of faces based on the projection of a striped pattern have …
Electronic Health Record System Evaluation Based On Patient Safety, Yung-Yu Su, Khin Than Win, John A. Fulcher
Electronic Health Record System Evaluation Based On Patient Safety, Yung-Yu Su, Khin Than Win, John A. Fulcher
Faculty of Informatics - Papers (Archive)
After describing the general characteristics of Electronic Health Records (EHRs), we consider patient safety. We then proceed to discuss IS evaluation in general terms, followed by HIS system evaluation in particular. The D&M IS Success model, Technology Acceptance model and Task-Technology Fit model are considered as potential candidates for EHR System evaluation. Based upon a critical review of the available literature, we draw some conclusions about the appropriateness of current HIS/EHR evaluation approaches. Finally, we suggest that by incorporating patient safety attributes in any EHR System evaluation framework, then this could lead to improved accuracy, and in turn improved patient …
Power System Applications Of Superconducting Magnetic Energy Storage Systems, X D. Xue, Eric Kw Cheng, Danny Sutanto
Power System Applications Of Superconducting Magnetic Energy Storage Systems, X D. Xue, Eric Kw Cheng, Danny Sutanto
Faculty of Informatics - Papers (Archive)
This study overviewed current researches on power system applications of SMES systems. Some key schematic diagrams of applications were given, too. Furthermore, the authors tried to present a few valuable suggestions for future studies of SMES applications to power systems.
An Adaptive Scalable Multiuser-Ofdm System For Multimedia Transmission Over Fading Channels, Ahmed Muthana M. Nadhim, Jianhua He, Jiangtao Xi, Zongkai Yang
An Adaptive Scalable Multiuser-Ofdm System For Multimedia Transmission Over Fading Channels, Ahmed Muthana M. Nadhim, Jianhua He, Jiangtao Xi, Zongkai Yang
Faculty of Informatics - Papers (Archive)
In this paper, an adaptive scalable multiuser-OFDM system was proposed for multimedia transmission over fading channels. The proposed adaptive algorithm can adapt according to the channel status information of each user's channel status. This algorithm dynamically changes according to the user's channel changes; this can keep fixed QoS at the physical layer. Another predefined QoS for different sessions and services to be provided for different users. This QoS can be guaranteed by multimedia scalability. Scalability can adapt to the service requirements, in terms of transmission data rate and bandwidth. As a result, a robust multimedia transmission scheme is achieved by …