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Investigating The Effect Of Participation-Limiting Structures On Outcomes Of E-Democracy Systems (Research In Progress), Rajeev Sharma Dec 2012

Investigating The Effect Of Participation-Limiting Structures On Outcomes Of E-Democracy Systems (Research In Progress), Rajeev Sharma

Professor Rajeev Sharma

Modern information systems provide a technical foundation for greater participation of citizens in the agenda-setting and decision-making processes of government. Information systems researchers and designers will need to address a number of issues to design IS applications for the effective functioning of evolving forms of democracy. This paper identifies a research agenda at the intersection of information systems research, economics and political science research and avenues for information systems researchers to contribute to the research agenda.


Partners Selection In Multi-Agent Systems By Using Linear And Non-Linear Approaches, Minjie Zhang, Fenghui Ren Nov 2012

Partners Selection In Multi-Agent Systems By Using Linear And Non-Linear Approaches, Minjie Zhang, Fenghui Ren

Dr Fenghui Ren

No abstract provided.


Using Colored Petri Nets To Predict Future States In Agent-Based Scheduling And Planning Systems, Minjie Zhang, John Fulcher, Quan Bai, Fenghui Ren Nov 2012

Using Colored Petri Nets To Predict Future States In Agent-Based Scheduling And Planning Systems, Minjie Zhang, John Fulcher, Quan Bai, Fenghui Ren

Dr Fenghui Ren

No abstract provided.


Coupling Biophysical And Socioeconomic Models For Coral Reef Systems In Quintana Roo, Mexican Caribbean, Deborah Cleland, Jess Melbourne-Thomas, Craig Johnson, Pascal Perez, Jeremy Eustache, Elizabeth Fulton Nov 2012

Coupling Biophysical And Socioeconomic Models For Coral Reef Systems In Quintana Roo, Mexican Caribbean, Deborah Cleland, Jess Melbourne-Thomas, Craig Johnson, Pascal Perez, Jeremy Eustache, Elizabeth Fulton

Professor Pascal Perez

No abstract provided.


Embracing Social Uncertainties With Complex Systems Science, Pascal Perez Nov 2012

Embracing Social Uncertainties With Complex Systems Science, Pascal Perez

Professor Pascal Perez

Human ecosystems are real-life systems characterized by very strong and longterm interactions between human communities and their environment; as such they constitute an expansion of the ecological concept of ecosystem. According to Stepp and colleagues (2003), human ecosystems not only process matter and energy flows, but - and more specifically - information flows as well. Therefore, they display very specific characteristics due to our ability to communicate and learn from others, creating the conditions for co-evolutionary processes in which chance lends a hand to necessity. Bradbury (2006) argues that, until recently, human beings had been able to adapt to changes …


Flicker Transfer In Radial Power Systems, Sankika Tennakoon, Lakshal Perera, D A. Robinson, Sarath Perera Nov 2012

Flicker Transfer In Radial Power Systems, Sankika Tennakoon, Lakshal Perera, D A. Robinson, Sarath Perera

Associate Professor Sarath Perera

Loads which exhibit continuous and rapid variations in their current can cause voltage fluctuations that are often referred to as flicker. One good example for such loads is arc furnaces which are usually fed by dedicated feeders from the high voltage busbars in transmission systems. The flicker generated from such loads will propagate to the upstream HV point of common coupling (PCC), and from there to the downstream through the transmission and sub transmission systems. This paper demonstrates how the generated flicker is propagated from the HV PCC to the downstream in radial networks exhibiting different levels of attenuation depending …


The Application Of Iec 61000-3-6 To Mv Systems In Australia, Victor J. Gosbell, D A. Robinson, Sarath Perera, Alex Baitch Nov 2012

The Application Of Iec 61000-3-6 To Mv Systems In Australia, Victor J. Gosbell, D A. Robinson, Sarath Perera, Alex Baitch

Associate Professor Sarath Perera

IEC 61000-3-6 [1] comprises a number of stages and tests to determine harmonic emission allowances for customers connected to MV or HV networks. Of particular importance is the section concerning loads distributed along a feeder, each having a different fault level. Although a common situation, the treatment given in the IEC standard is poorly described, being largely illustrated by one atypical example. This allows simplifying assumptions to be made which are invalid in practical cases. This paper outlines a more general approach that is relatively easy to apply.


Support Of Distribution System Using Distributed Wind And Pv Systems, Kai Zou, Ashish P. Agalgaonkar, Kashem Muttaqi, Sarath Perera, N Browne Nov 2012

Support Of Distribution System Using Distributed Wind And Pv Systems, Kai Zou, Ashish P. Agalgaonkar, Kashem Muttaqi, Sarath Perera, N Browne

Associate Professor Sarath Perera

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 Unbalance Emission Assessment In Radial Power Systems, U Jayatunga, S Perera, P Ciufo Nov 2012

Voltage Unbalance Emission Assessment In Radial Power Systems, U Jayatunga, S Perera, P Ciufo

Associate Professor Sarath Perera

Voltage unbalance (VU) emission assessment is an integral part in the VU-management process where loads are allocated a portion of the unbalance absorption capacity of the power system. The International Electrotechnical Commission Report IEC/TR 61000-3-13:2008 prescribes a VU emission allocation methodology establishing the fact that the VU can arise at the point of common connection (PCC) due to upstream network unbalance and load unbalance. Although this is the case for emission allocation, approaches for post connection emission assessment do not exist except for cases where the load is the only contributor to the VU at the PCC. Such assessment methods …


Optimisation Of Distributed Generation Units And Shunt Capacitors For Economic Operation Of Distribution Systems, Kai Zou, Sarath Perera, Kashem Muttaqi, Ashish P. Agalgaonkar Nov 2012

Optimisation Of Distributed Generation Units And Shunt Capacitors For Economic Operation Of Distribution Systems, Kai Zou, Sarath Perera, Kashem Muttaqi, Ashish P. Agalgaonkar

Associate Professor Sarath Perera

The integration of Distributed Generation (DG) units and shunt capacitors can be considered as an alternative approach for distribution system expansion planning not only to improve power supply quality and reliability, but also to defer major system updates. In this paper, the techno-economic issues of distribution system expansion planning with optimal sizing and siting of DG units and shunt capacitors are addressed. The minimisation of overall investment cost with the integration of DG units and shunt capacitors is assessed with the consideration of supply quality, reliability and energy loss. A new planning methodology by using Particle Swarm Optimisation (PSO) is …


Review Of Flicker Objectives For Lv, Mv And Hv Systems, Detmar Arlt, Herivelto Bronzeado, Rong Cai, Emmanuel De Jaeger, Zia Emin, David Guillot, Mark Halpin, Naoki Kobayashi, Matti Lahtinen, Igor Papic, Francisco Pazos, Sarath Perera, Jeremy Price, Herwig Renner, Xavier Yang, Francisc Zavoda Nov 2012

Review Of Flicker Objectives For Lv, Mv And Hv Systems, Detmar Arlt, Herivelto Bronzeado, Rong Cai, Emmanuel De Jaeger, Zia Emin, David Guillot, Mark Halpin, Naoki Kobayashi, Matti Lahtinen, Igor Papic, Francisco Pazos, Sarath Perera, Jeremy Price, Herwig Renner, Xavier Yang, Francisc Zavoda

Associate Professor Sarath Perera

No abstract provided.


Control Of Energy Storage Interface With A Bidirectional Converter For Photovoltaic Systems, K.N Hasan, M.E Haque, Michael Negnevitsky, Kashem Muttaqi Nov 2012

Control Of Energy Storage Interface With A Bidirectional Converter For Photovoltaic Systems, K.N Hasan, M.E Haque, Michael Negnevitsky, Kashem Muttaqi

Associate Professor Kashem Muttaqi

Efficient energy storage is one of the greatest concerns for renewable power generation. This paper focuses on the control of a battery management system (BMS) for photovoltaic (PV) applications with a high efficiency bidirectional converter. The proposed BMS control strategy utilizes the dc bus power and battery state of charge (SOC) for the charging and discharging of the battery with a bidirectional converter. The bidirectional converter includes fewer components and switches, has less switching losses with zero voltage switching, and has high gain buck-boost operations. A new control algorithm of charging-discharging control for the battery storage system is proposed. The …


Support Of Distribution System Using Distributed Wind And Pv Systems, Kai Zou, Ashish P. Agalgaonkar, Kashem Muttaqi, Sarath Perera, N Browne Nov 2012

Support Of Distribution System Using Distributed Wind And Pv Systems, Kai Zou, Ashish P. Agalgaonkar, Kashem Muttaqi, Sarath Perera, N Browne

Associate Professor Kashem Muttaqi

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 …


Optimisation Of Distributed Generation Units And Shunt Capacitors For Economic Operation Of Distribution Systems, Kai Zou, Sarath Perera, Kashem Muttaqi, Ashish P. Agalgaonkar Nov 2012

Optimisation Of Distributed Generation Units And Shunt Capacitors For Economic Operation Of Distribution Systems, Kai Zou, Sarath Perera, Kashem Muttaqi, Ashish P. Agalgaonkar

Associate Professor Kashem Muttaqi

The integration of Distributed Generation (DG) units and shunt capacitors can be considered as an alternative approach for distribution system expansion planning not only to improve power supply quality and reliability, but also to defer major system updates. In this paper, the techno-economic issues of distribution system expansion planning with optimal sizing and siting of DG units and shunt capacitors are addressed. The minimisation of overall investment cost with the integration of DG units and shunt capacitors is assessed with the consideration of supply quality, reliability and energy loss. A new planning methodology by using Particle Swarm Optimisation (PSO) is …


Output Quality Evaluation Of Photovoltaic Systems With Different Current Control Methods Of Switch-Mode Converters, K. N. Hasan, Md Enamul Haque, Michael Negnevitsky, Kashem Muttaqi Nov 2012

Output Quality Evaluation Of Photovoltaic Systems With Different Current Control Methods Of Switch-Mode Converters, K. N. Hasan, Md Enamul Haque, Michael Negnevitsky, Kashem Muttaqi

Associate Professor Kashem Muttaqi

This paper presents a comparative assessment of the current control methods (CCM) of switch-mode converters for photovoltaic (PV) applications. In this paper, average current control, current programmed control, hysteresis current control and nonlinear carrier control methods are addressed considering input fluctuations and load variations for PV systems. Dynamic responses of PV systems are investigated and harmonic analysis is performed. Performances of the above current controllers are examined through simulation and the results are presented. The results show that the selection of different current control techniques depends on the working conditions and the area of applications.


Dynamic Universal Accumulators For Ddh Groups And Their Application To Attribute-Based Anonymous Credential Systems, Man Ho Au, Patrick P. Tsang, Willy Susilo, Yi Mu Nov 2012

Dynamic Universal Accumulators For Ddh Groups And Their Application To Attribute-Based Anonymous Credential Systems, Man Ho Au, Patrick P. Tsang, Willy Susilo, Yi Mu

Professor Yi Mu

We present the first dynamic universal accumulator that allows (1) the accumulation of elements in a DDH-hard group G and (2) one who knows x such that y = gx has - or has not - been accumulated, where g generates G, to efficiently prove her knowledge of such x in zero knowledge, and hence without revealing, e.g., x or y. We introduce the Attribute-Based Anonymous Credential System, which allows the verifier to authenticate anonymous users according to any access control policy expressible as a formula of possibly negated boolean user attributes. We construct the system from our accumulator.


Optimization Of Task Processing Schedules In Distributed Information Systems, Janusz R. Getta Nov 2012

Optimization Of Task Processing Schedules In Distributed Information Systems, Janusz R. Getta

Dr Janusz Getta

The performance of data processing in distributed information systems strongly depends on theefficient scheduling of the applications that access data at the remote sites. This work assumes atypical model of distributed information system where a central site is connected to a number ofremote and highly autonomous remote sites. An application started by a user at a central site isdecomposed into several data processing tasks to be independently processed at the remote sites.The objective of this work is to find a method for optimization of task processing schedules at acentral site. We define an abstract model of data and a system …


Evaluating The Implementation Of Emr Systems From The Perspective Of Health Professionals, Yung-Yu Su, John A. Fulcher, Khin Than Win, Herng-Chia Chiu, Gui-Fen Chiu Nov 2012

Evaluating The Implementation Of Emr Systems From The Perspective Of Health Professionals, Yung-Yu Su, John A. Fulcher, Khin Than Win, Herng-Chia Chiu, Gui-Fen Chiu

Professor John Fulcher

In health informatics, the "updated DeLone and McLean IS success model" is reviewed as a mature model in measuring health information system (HIS) success. This research provided an evaluation model to estimate the implementation of electronic medical records (EMR) systems from a health professional perspective by combined the updated DeLone and McLean IS success model, data quality management model, and EMR systems safety attributes. Based on evidence-based management (EBM), this research could be regarded as an empirical example for further EMR systems research since it not only provided a model to measure the Taiwanese EMR systems in two hospitals by …


Automated Change Impact Analysis For Agent Systems, Aditya Ghose, Hoa Dam Nov 2012

Automated Change Impact Analysis For Agent Systems, Aditya Ghose, Hoa Dam

Dr Hoa Dam

Intelligent agent technology has evolved rapidly over the past few years along with the growing number of agent systems in various domains. Although a substantial amount of work in agent-oriented software engineering has provided methodologies for analysing, designing and implementing agent-based systems, recent studies have highlighted that there has been very little work on maintenance and evolution of agent-based systems. A critical issue in software maintenance and evolution is change impact analysis: determining the potential consequences of a proposed change. There has been a proliferation of techniques proposed to support change impact analysis of procedural or object-oriented systems, but to …


Mindful It Adoption: Making The Right Strategic Decisions By Knowing Why And How To Adopt Enterprise Systems?, Valerie A. Baker, Tim Coltman Nov 2012

Mindful It Adoption: Making The Right Strategic Decisions By Knowing Why And How To Adopt Enterprise Systems?, Valerie A. Baker, Tim Coltman

Tim Coltman

Corporate investment in enterprise level IT systems has been characterised by high rates of failure. The paper presents a knowledge based perspective to examine how firms adopt and implement enterprise systems in order to better understand how organisations can achieve reliable outcomes from such investments. The case presented explores the key decision stages of a major ERP investment, focusing on the strategic reasoning behind each decision. Particular attention is directed to the relationship between adoption know-why and implementation know-how to assess whether managers have been mindful or mindless in their investment decisions.


Dynamic Universal Accumulators For Ddh Groups And Their Application To Attribute-Based Anonymous Credential Systems, Man Ho Au, Patrick P. Tsang, Willy Susilo, Yi Mu Oct 2012

Dynamic Universal Accumulators For Ddh Groups And Their Application To Attribute-Based Anonymous Credential Systems, Man Ho Au, Patrick P. Tsang, Willy Susilo, Yi Mu

Dr Man Ho Allen Au

We present the first dynamic universal accumulator that allows (1) the accumulation of elements in a DDH-hard group G and (2) one who knows x such that y = gx has - or has not - been accumulated, where g generates G, to efficiently prove her knowledge of such x in zero knowledge, and hence without revealing, e.g., x or y. We introduce the Attribute-Based Anonymous Credential System, which allows the verifier to authenticate anonymous users according to any access control policy expressible as a formula of possibly negated boolean user attributes. We construct the system from our accumulator.


Design Of A High Temperature Superconductor Magnetic Energy Storage Systems, R L Causley, Christopher Cook, Steve Gower Aug 2012

Design Of A High Temperature Superconductor Magnetic Energy Storage Systems, R L Causley, Christopher Cook, Steve Gower

Christopher Cook

The University of Wollongong (UoW) has received funding for the research and development of a 20 kJ high temperature superconducting magnetic energy storage device (HTS SMES). This SMES will be operated at 25 K in contrast to most existing HTS designs, which operate at 77K. This paper includes a literature review of the current technology for the configuration of the SMES coil and a summary of the work done at UoW to date. Solenoidal and toroidal coils designs are compared to determine which will provide the required level of energy stored for a minimum superconductor and device volume. The design …


Using Task Analysis To Design Intuitive Online Grocery Systems, Mark Freeman, Alison Freeman Mar 2012

Using Task Analysis To Design Intuitive Online Grocery Systems, Mark Freeman, Alison Freeman

Dr Mark Freeman

This paper presents a normative task model for modelling user interactions with online grocery stores. It is envisaged that using task models will aid system developers in building better systems to meet users’ needs, and hereby creating better system design processes. This paper will discuss the three main areas of user experience when completing the process of adding a product to an online trolley: attempting to retrieve the product, receiving the results of the retrieval attempt, and adding the product to the trolley. The normative task model presented is expected to help in the future design of online grocery systems …


Developing The Next Generation Of Women And Minority Scientists For The Nuclear Energy Industry, Darrell Burrell, Andrea Todd, Aikyna Finch, Maurice Dawson Dec 2011

Developing The Next Generation Of Women And Minority Scientists For The Nuclear Energy Industry, Darrell Burrell, Andrea Todd, Aikyna Finch, Maurice Dawson

Maurice Dawson

The largest source of carbon dioxide emissions globally is the combustion of fossil fuels (coal, oil and natural gas) in power plants, automobiles, industrial facilities and other sources. Generating electricity is the single largest source of carbon dioxide emissions, representing 41% of all emissions. Since 2007 the United States has been more actively considering nuclear power as an option for developing energy. Three decades after the Three Mile Island accident seemed to doom the nuclear power industry, the idea of a nuclear renaissance has been gaining public acceptance as a way to generate energy without greenhouse gas emissions and meet …