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University of Wollongong

Faculty of Informatics - Papers (Archive)

Series

2011

System

Articles 1 - 5 of 5

Full-Text Articles in Physical Sciences and Mathematics

An Analysis Of An Activated Sludge Process Containing A Sludge Disintegration System, Mark I. Nelson, Easwaran Balakrishnan Jan 2011

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 Jan 2011

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 Jan 2011

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 Jan 2011

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 Jan 2011

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 …