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Full-Text Articles in Physical Sciences and Mathematics
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 …
Multiresonator-Based Chipless Rfid System For Low-Cost Item Tracking, Stevan Preradovic, Isaac Balbin, Nemai Karmakar, Gerhard F. Swiegers
Multiresonator-Based Chipless Rfid System For Low-Cost Item Tracking, Stevan Preradovic, Isaac Balbin, Nemai Karmakar, Gerhard F. Swiegers
Faculty of Science - Papers (Archive)
A fully passive printable chipless RFID system is presented. The chipless tag uses the amplitude and phase of the spectral signature of a multiresonator circuit and provides I : 1 correspondence of data bits. The tag comprises of a microstrip spiral multiresonator and cross-polarized transmitting and receiving microstrip ultra-wideband disc loaded monopole antennas. The reader antenna is a log periodic dipole antenna with average 5.5-dBi gain. Firstly, a 6-bit chipless tag is designed to encode 000000 and 010101 IDs. Finally, a 35-bit chipless tag based on the same principle is presented. The tag has potentials for low-cost item tagging such …
Development And Application Of A System For The Analysis Of Atmospheric, Water And Sediment Nitrogen And Carbon, Ann Stavert, Stephen R. Wilson, Dianne F. Jolley
Development And Application Of A System For The Analysis Of Atmospheric, Water And Sediment Nitrogen And Carbon, Ann Stavert, Stephen R. Wilson, Dianne F. Jolley
Faculty of Science - Papers (Archive)
Eutrophication and climate change, key environmental concerns, are both linked to the carbon and nitrogen cycles hence the improved understanding of these cycles is essential. Currently, there is no system that simultaneously measures the fluxes of the three key gas phase products of nitrogen and carbon cycling (CO2, CH4 and N2O) in submerged ecosystems with hourly time resolution. A “Lake-in-a-box” (mesocosm) was developed in the laboratory which allowed the monitoring of key components of the carbon and nitrogen cycles within the air, water and sediments. The approach is automated, simple and time efficient and novel in its ability to examine …
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, …
A Novel Chipless Rfid System Based On Planar Multiresonators For Barcode Replacement, Stevan Preradovic, Isaac Balbin, Nemai Karmakar, Gerry Swiegers
A Novel Chipless Rfid System Based On Planar Multiresonators For Barcode Replacement, Stevan Preradovic, Isaac Balbin, Nemai Karmakar, Gerry Swiegers
Australian Institute for Innovative Materials - Papers
RFID is taking the world by storm but lowering the price of the tag is a necessity in order to completely replace barcode systems with RFID systems. Researchers around the world have been working on chipless RFID systems. In this paper we present a novel chipless RFID system for barcode replacement. The system can be effectively used in conveyor belt applications. It uses spectral signatures to encoded data and hence provide a unique ID for every tagged object. The chipless tag is fully passive and planar.
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 …
A Task Model Of Software Intensive Acquisitions: An Integrated Tactical Avionics System Case Study, Ricardo Peculis, Derek Rogers, Peter Campbell
A Task Model Of Software Intensive Acquisitions: An Integrated Tactical Avionics System Case Study, Ricardo Peculis, Derek Rogers, Peter Campbell
SMART Infrastructure Facility - Papers
The acquisition of complex software intensive systems is fraught with significant risks and often incurs schedule delays, cost overruns and reduced functionality when the product is finally delivered. This paper presents a model to assess the effectiveness of software intensive acquisitions, founded on the premise that the solution depends on a series of transformations that transform input products in one domain into output products in another domain. Transformations are performed by people, and require knowledge and skills pertinent to both input and output domains. Ideally, products should be transformed without distortions resulting into the desirable solution. In reality, distortions occur …
Conducting Polymers With Fibrillar Morphology Synthesized In A Biphasic Ionic Liquid/Water System, J.M. Pringle, Orawan Ngamna, Carol M. Lynam, Gordon G. Wallace, Maria Forsyth, Douglas Macfarlane
Conducting Polymers With Fibrillar Morphology Synthesized In A Biphasic Ionic Liquid/Water System, J.M. Pringle, Orawan Ngamna, Carol M. Lynam, Gordon G. Wallace, Maria Forsyth, Douglas Macfarlane
Faculty of Science - Papers (Archive)
The synthesis of poly(pyrrole), poly(terthiophene), and poly(3,4-ethylenedioxythiophene) with unusual fibrillar morphologies has been achieved by chemical polymerization in a biphasic ionic liquid/water system. Use of aqueous gold chloride as the oxidant, with the monomers dissolved in a hydrophobic ionic liquid, allows the polymerization to occur at the ionic liquid/water interface. The resultant conducting polymer fibrils are, on average, 50−100 nm wide and can be thousands of nanometers long. The polymers produced in this ionic liquid system are compared to those synthesized in a biphasic chloroform/water system.
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 …
Investigation Of Large-Scale Washover Of A Small Barrier System On The Southeast Australian Coast Using Ground Penetrating Radar, Brian G. Jones, C Bristow, Adam D. Switzer
Investigation Of Large-Scale Washover Of A Small Barrier System On The Southeast Australian Coast Using Ground Penetrating Radar, Brian G. Jones, C Bristow, Adam D. Switzer
Faculty of Science - Papers (Archive)
Prehistoric depositional signatures for large-scale washover involving marine inundation events such as storm and tsunami have been the subject of considerable research over the last 15 years. Much of this research has focused on the identification of sand sheets in back-barrier environments as depositional records for extreme washover events. All these deposits must have a sediment source, and by their nature, the most likely source of sediment for washover into back-barrier environments is the barrier itself. This study identifies an erosional signature for large-scale washover from a small coastal barrier on the southeast Australian coast. A distinct lense of marine …
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 …
Signal Processing Methods Implemented In A Novel Fbg Sensing System For Vibration/Dynamic Strain Measurement, Xingyuan Xu, Enbang Li, Jiangtao Xi, Joe F. Chicharo
Signal Processing Methods Implemented In A Novel Fbg Sensing System For Vibration/Dynamic Strain Measurement, Xingyuan Xu, Enbang Li, Jiangtao Xi, Joe F. Chicharo
Faculty of Informatics - Papers (Archive)
We have demonstrated a novel Fiber Bragg Grating sensing system based on a Fabry-Perot tunable filter for measuring dynamic processes. This system is very suitable for multipoint vibration or dynamic strain detection. However, in some conditions, the response time of Fabry-Perot tunable filter will influence the sensitivity of the sensor that the sensitivity is not kept constant. Therefore, post-processing for the measured vibration signal is necessary to solve this problem. In this paper, the demodulation technique of this system is briefly described and two signal processing methods are introduced to deal with the measured signal to obtain stable measurement of …
Magnetic And Transport Properties Of The Layered Perovskite System Sr2-Yyycoo4 (0< Y < 1), Xiaolin Wang, E Takayama-Muromachi
Magnetic And Transport Properties Of The Layered Perovskite System Sr2-Yyycoo4 (0< Y < 1), Xiaolin Wang, E Takayama-Muromachi
Australian Institute for Innovative Materials - Papers
Layered perovskite cobalt oxides Sr2-yYyCoO4 (y=0, 0.1, 0.3, 0.5, 0.67, 0.83 and 1) were synthesized under high pressure and high temperature conditions.
A Study On Solid Waste Management System Of Dhaka City Corporation: Effect Of Composting And Landfill Location, Faisal Ibney Hai, M. Ashraf Ali
A Study On Solid Waste Management System Of Dhaka City Corporation: Effect Of Composting And Landfill Location, Faisal Ibney Hai, M. Ashraf Ali
Faculty of Science - Papers (Archive)
This study has analyzed the generation and characteristics of solid waste in Dhaka city, along with the associated environmental impacts and existing solid waste management practices. Special focus was given on the effect of composting on final disposal of solid waste and effect of landfill site location on transportation cost. An estimate of the future generation rate indicates that the present generation rate of 3500 tons/day may exceed 30 thousand tons/day by the year 2020.The mixed waste dumped at dumping sites is characterized with high organic content and high moisture content (about 80% and 50-70% by weight, respectively). According to …
Harmonic Survey Of An Mv Distribution System, Victor J. Gosbell, Damian Mannix, D A. Robinson, Sarath Perera
Harmonic Survey Of An Mv Distribution System, Victor J. Gosbell, Damian Mannix, D A. Robinson, Sarath Perera
Faculty of Informatics - Papers (Archive)
The harmonic survey of a medium voltage distribution system involves three major aspects: (i) the choice of harmonic monitor, (ii) the choice of monitoring site, (iii) processing and presentation of results. As well as a discussion of the methodology for these aspects, the paper will discuss the harmonic levels measured, the minimum survey requirements for finding useful data and the harmonic parameters of residential, commercial and industrial loads.