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Full-Text Articles in Physical Sciences and Mathematics

Assessing Infrastructure System Of Systems Integrity, Ricardo Peculis, Farid Shirvani, Pascal Perez Jan 2017

Assessing Infrastructure System Of Systems Integrity, Ricardo Peculis, Farid Shirvani, Pascal Perez

SMART Infrastructure Facility - Papers

Infrastructure refers to the fundamental facilities and systems serving a country, city, or area, including the services and facilities necessary for its economy to function. Infrastructure systems typically consist of interrelated constituent systems forming what is known as system of systems (SoS). Infrastructure systems present numerous challenges throughout their lifecycles. This paper addresses one of these challenges that is presented during operation, when managers need to report 'how well' the system is performing and finding ways to address the consequences of unexpected events that often degrade the intended performance. This state of system 'wellbeing' will be referred as system integrity …


Lifelong Machine Learning With Adaptive Multi-Agent Systems, Nicolas R. Verstaevel, Jeremy Boes, Julien Nigon, Dorian D'Amico, Marie-Pierre Gleizes Jan 2017

Lifelong Machine Learning With Adaptive Multi-Agent Systems, Nicolas R. Verstaevel, Jeremy Boes, Julien Nigon, Dorian D'Amico, Marie-Pierre Gleizes

SMART Infrastructure Facility - Papers

Sensors and actuators are progressively invading our everyday life as well as industrial processes. They form complex and pervasive systems usually called "ambient systems" or "cyber-physical systems". These systems are supposed to efficiently perform various and dynamic tasks in an ever-changing environment. They need to be able to learn and to self-adapt throughout their life, because designers cannot specify a priori all the interactions and situations they will face. These are strong requirements that push the need for lifelong machine learning, where devices can learn models and behaviours during their whole lifetime and are able to transfer them to perform …


Infrastructure System Of Systems Integrity, Ricardo Peculis, Farid Shirvani Jan 2017

Infrastructure System Of Systems Integrity, Ricardo Peculis, Farid Shirvani

SMART Infrastructure Facility - Papers

Infrastructure systems typically consist of technical structures comprising of physical and operational components of interrelated constituent systems forming what is now known as system of systems (SOS). The complexity and uncertainty of unforeseen events that are inherent characteristic of infrastructure systems makes it impossible to predict undesirable emergent behaviours that could push the operation of such systems away from their intended purposes. Infrastructure systems present numerous challenges throughout their lifecycles. This paper addresses one of these challenges that is presented during operation, when managers need to report 'how well' the system is performing and find ways to address the consequences …


Systematic Elongation Of Thienyl Linkers And Their Effect On Optical And Electrochemical Properties In Carbazole-Bodipy Donor-Acceptor Systems, Alina Brzeczek, Katarzyna Piwowar, Wojciech Domagala, Mikotaj M. Mikotajczyk, Krzysztof Walczak, Pawel W. Wagner Jan 2016

Systematic Elongation Of Thienyl Linkers And Their Effect On Optical And Electrochemical Properties In Carbazole-Bodipy Donor-Acceptor Systems, Alina Brzeczek, Katarzyna Piwowar, Wojciech Domagala, Mikotaj M. Mikotajczyk, Krzysztof Walczak, Pawel W. Wagner

Australian Institute for Innovative Materials - Papers

Synthesis, spectral and electrochemical properties of a series of new panchromatic BODIPY donor-acceptor-donor derivatives, comprising carbazole conjugated with systematically elongated framework by thiophene-based linkers were investigated. It has been found that elongation of the π-system with one thiophene unit shifts the spectra toward near infrared, while incorporation of next thiophene derivatives has only limited influence on the lowest energy transition, causing no further shift of absorption maxima. Elongation of π-conjugation of the donor arm tunes the electron properties, influencing the ionization potential (IP) and electron affinity (EA) values of the molecules. The experimental results are supported by quantum chemical computations …


Case Study: A Model Based Systems Engineering (Mbse) Framework For Characterising Transportation Systems Over The Full Life Cycle, William R. Scott, Richard Fullalove, Gary Arabian, Allan P. Campbell Jan 2016

Case Study: A Model Based Systems Engineering (Mbse) Framework For Characterising Transportation Systems Over The Full Life Cycle, William R. Scott, Richard Fullalove, Gary Arabian, Allan P. Campbell

SMART Infrastructure Facility - Papers

Development of transport infrastructure has significant challenges including acquisition lag, phased evolution, multiple disparate stakeholders and environment-specific issues. The Asset Standards Authority (ASA) at TfNSW is introducing MBSE to address these challenges. Instrumental to the introduction is the development of a framework that structures the available data and provides guidance and traceability between the data sets. This framework combines the enterprise-level drivers with the lower level drivers such as standards to outline a generic conceptual design for a transport system. This conceptual design is then used to guide future system development. The outcome is future project information based on greater, …


Porous Nanoarchitectures Of Spinel-Type Transition Metal Oxides For Electrochemical Energy Storage Systems, Min-Sik Park, Jeonghun Kim, Ki Jae Kim, Jongwon Lee, Jung Ho Kim, Yusuke Yamauchi Jan 2015

Porous Nanoarchitectures Of Spinel-Type Transition Metal Oxides For Electrochemical Energy Storage Systems, Min-Sik Park, Jeonghun Kim, Ki Jae Kim, Jongwon Lee, Jung Ho Kim, Yusuke Yamauchi

Australian Institute for Innovative Materials - Papers

Transition metal oxides possessing two kinds of metals (denoted as AxB3-xO4, which is generally defined as a spinel structure; A, B = Co, Ni, Zn, Mn, Fe, etc.), with stoichiometric or even non-stoichiometric compositions, have recently attracted great interest in electrochemical energy storage systems (ESSs). The spinel-type transition metal oxides exhibit outstanding electrochemical activity and stability, and thus, they can play a key role in realising cost-effective and environmentally friendly ESSs. Moreover, porous nanoarchitectures can offer a large number of electrochemically active sites and, at the same time, facilitate transport of charge carriers (electrons and ions) during energy storage reactions. …


3-Dimensional (3d) Fabricated Polymer Based Drug Delivery Systems, Simon Moulton, Gordon G. Wallace Jan 2014

3-Dimensional (3d) Fabricated Polymer Based Drug Delivery Systems, Simon Moulton, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Drug delivery from 3-dimensional (3D) structures is a rapidly growing area of research. It is essential to achieve structures wherein drug stability is ensured, the drug loading capacity is appropriate and the desired controlled release profile can be attained. Attention must also be paid to the development of appropriate fabrication machinery that allows 3D drug delivery systems (DDS) to be produced in a simple, reliable and reproducible manner. The range of fabrication methods currently being used to form 3D DDSs include electrospinning (solution and melt), wet-spinning and printing (3-dimensional). The use of these techniques enables production of DDSs from the …


The Nanostructure Of Three-Dimensional Scaffolds Enhances The Current Density Of Microbial Bioelectrochemical Systems, Victoria Flexer, Jun Chen, Bogdan C. Donose, Peter C. Sherrell, Gordon G. Wallace, Jurg Keller Jan 2013

The Nanostructure Of Three-Dimensional Scaffolds Enhances The Current Density Of Microbial Bioelectrochemical Systems, Victoria Flexer, Jun Chen, Bogdan C. Donose, Peter C. Sherrell, Gordon G. Wallace, Jurg Keller

Australian Institute for Innovative Materials - Papers

Bioelectrochemical systems encompass a range of electrochemical systems wherein microorganisms are used as biocatalysts. These range from classical microbial fuel cells to novel microbial electrosynthesis processes. The future of practical applications relies on increased performance. In all cases the development of new electrode materials is essential to overcome the low current densities of bioelectrochemical systems. Here we describe a new biocompatible, highly conductive three-dimensional scaffold electrode, NanoWeb-RVC, with a hierarchical porous structure, synthesized by direct growth of carbon nanotubes on a macroporous substrate. The nanostructure of these electrodes enhances the rate of bacterial extracellular electron transfer while the macrostructure ensures …


Modelling And Data Frameworks For Understanding Infrastructure Systems Throuh A Systems-Of-Systems Lens, Matthew J. Berryman, Rohan Wickramasuriya, Vu Lam Cao, Pascal Perez Jan 2013

Modelling And Data Frameworks For Understanding Infrastructure Systems Throuh A Systems-Of-Systems Lens, Matthew J. Berryman, Rohan Wickramasuriya, Vu Lam Cao, Pascal Perez

SMART Infrastructure Facility - Papers

Modelling and analysis of large systems of infrastructure systems carries with it a number of challenges, in particular around the volume of data and the requisite complexity (and thus computing resources required) of models. In this paper we present an integrated land use–transportation model of a region in Sydney, and detail how we integrated an agent-based model of location and transport choice with a traffic micro-simulator. We also discuss both some novel architectures for scalability of modelling as well as for fusion and relevant visualisation of large data sets. We have a particular focus on geospatial infrastructure data visualisation.


The Electrochemical Properties Of High-Capacity Sulfur/Reduced Graphene Oxide With Different Electrolyte Systems, Yunxiao Wang, Shulei Chou, Hua-Kun Liu, S X. Dou Jan 2013

The Electrochemical Properties Of High-Capacity Sulfur/Reduced Graphene Oxide With Different Electrolyte Systems, Yunxiao Wang, Shulei Chou, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

The lithium/sulfur battery is a promising electrochemical system with high capacity, which is well-known to undergo a complex multistep reaction during the discharge process. Two types of electrolytes including poly (ethylene glycol) dimethyl ether (PEGDME)-based and 1.3 - dioxolane (DOL)/ dimethoxyethane (DME)-based electrolytes were investigated here. Furthermore, LiNO3 additive was introduced into the electrolyte in order to effectively eliminate the overcharge effect. The lithium sulfur battery with 1.0 M LiN(CF3SO2)2 in PEGME with 0.1 M LiNo3 shows highly stable reversible capacity of 624.8 mAh g-1 after 200 cycles and improved average coulombic efficiency of 98 percent.


A Novel Approach To Data Deduplication Over The Engineering-Oriented Cloud Systems, Zhe Sun, Jun Shen, Jianming Young Jan 2013

A Novel Approach To Data Deduplication Over The Engineering-Oriented Cloud Systems, Zhe Sun, Jun Shen, Jianming Young

Faculty of Informatics - Papers (Archive)

This paper presents a duplication-less storage system over the engineering-oriented cloud computing platforms. Our deduplication storage system, which manages data and duplication over the cloud system, consists of two major components, a front-end deduplication application and a mass storage system as back-end. Hadoop distributed file system (HDFS) is a common distribution file system on the cloud, which is used with Hadoop database (HBase). We use HDFS to build up a mass storage system and employ HBase to build up a fast indexing system. With a deduplication application, a scalable and parallel deduplicated cloud storage system can be effectively built up. …


Online Grocery Systems Design Through Task Analysis, Mark Freeman, Alison Freeman Jan 2011

Online Grocery Systems Design Through Task Analysis, Mark Freeman, Alison Freeman

Faculty of Informatics - Papers (Archive)

Purpose – Modelling users’ interactions online is envisaged to allow developers to increase the usability of online systems and will aid system developers in building better systems to meet users’ needs, hereby creating better system design processes. Design/methodology/approach – The normative task model that was developed in this paper was created through an expert review of 14 online grocery stores, using a reverse engineering technique to model the features of the stores’ ordering process. Findings – The research identified three main areas of user experience when undertaking the process of adding a product to an online trolley: attempting to retrieve …


Optimization Of Task Processing Schedules In Distributed Information Systems, Janusz R. Getta Jan 2011

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

Faculty of Informatics - Papers (Archive)

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 …


Investigating The Effect Of Participation-Limiting Structures On Outcomes Of E-Democracy Systems (Research In Progress), Rajeev Sharma Jan 2011

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

Faculty of Informatics - Papers (Archive)

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.


The Application Of Location Based Services In National Emergency Warning Systems: Sms, Cell Broadcast Services And Beyond, Anas Aloudat, Katina Michael Jan 2011

The Application Of Location Based Services In National Emergency Warning Systems: Sms, Cell Broadcast Services And Beyond, Anas Aloudat, Katina Michael

Faculty of Informatics - Papers (Archive)

Location-based services can be broadly defined as any service that provides information pertinent to the current location of an active mobile handset at a specific window of time, regardless of the underlying delivery technology used to convey its information. To date, the short message service and cell broadcast service have been utilised by several countries during emergencies, however the future indicates that these services while cost-effective today, will almost certainly be superseded in the next five to ten years by newer more powerful capabilities. The path forward in location-based emergency services in Australia is given against a backdrop of the …


A Preliminary Investigation Of Complex Adaptive Systems As A Model For Explaining Organisational Change Caused By The Introduction Of Health Information Systems, Kieren Diment, Ping Yu, Karin Garrety Jan 2011

A Preliminary Investigation Of Complex Adaptive Systems As A Model For Explaining Organisational Change Caused By The Introduction Of Health Information Systems, Kieren Diment, Ping Yu, Karin Garrety

Faculty of Informatics - Papers (Archive)

This paper documents the preliminary development of a framework for evaluating organisational change processes during the implementation of an electronic nursing documentation system in residential aged care facilities. It starts with a brief outline of organisational change processes. This is followed by a more detailed exposition of the principles underlying complex adaptive systems (CAS) theory, where we explain how mathematical concepts can be used to illuminate qualitative research approaches. Finally we present some preliminary findings on the facilitators and barriers for the introduction of the electronic documentation system, explained with reference to the CAS theory, based on analysis of interviews …


Supporting Developers In Complex Systems Modelling, Antonio A. Lopez-Lorca, Ghassan Beydoun, Rodrigo Martinez-Bejar, Holly Tootell Jan 2011

Supporting Developers In Complex Systems Modelling, Antonio A. Lopez-Lorca, Ghassan Beydoun, Rodrigo Martinez-Bejar, Holly Tootell

Faculty of Informatics - Papers (Archive)

Development of complex systems often requires building a large number of models with many interconnections and dependencies among them. The success of a project can be compromised by cognitive overload or limits of developers, who might miss relationships between elements of the models. Developing Multi-Agent Systems (MAS) is a typical example of where this may occur. Despite of its potential, this technology has not yet been widely adopted by industry due to its complexity and frequent errors in modelling activities. These errors typically propagate to later phases of the MAS development lifecycle, becoming costlier to fix and then lowering the …


A Multi-Method Approach To Evaluate Health Information Systems, Ping Yu Jan 2010

A Multi-Method Approach To Evaluate Health Information Systems, Ping Yu

Faculty of Informatics - Papers (Archive)

Systematic evaluation of the introduction and impact of health information systems (HIS) is a challenging task. As the implementation is a dynamic process, with diverse issues emerge at various stages of system introduction, it is challenge to weigh the contribution of various factors and differentiate the critical ones. A conceptual framework will be helpful in guiding the evaluation effort; otherwise data collection may not be comprehensive and accurate. This may again lead to inadequate interpretation of the phenomena under study. Based on comprehensive literature research and own practice of evaluating health information systems, the author proposes a multimethod approach that …


Using Task Analysis To Design Intuitive Online Grocery Systems, Mark Freeman, Alison Freeman Jan 2010

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

Faculty of Informatics - Papers (Archive)

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 …


Monitoring Intelligent Distribution Power Systems: A Power Quality Plan, Neil R. Browne, Timothy J. Browne, Sean T. Elphick Jan 2010

Monitoring Intelligent Distribution Power Systems: A Power Quality Plan, Neil R. Browne, Timothy J. Browne, Sean T. Elphick

Faculty of Informatics - Papers (Archive)

Power system monitoring capabilities and requirements are evolving rapidly. The traditional monitoring framework in Australian distribution networks involves biannual readings of maximum demand at each distribution substation. As utilities respond to developments in metering and communications technology, automated collection and retrieval of quasi-real-time system data between substations and central repositories is now feasible. This gives network managers a significantly increased understanding of distribution network dynamic activity such as daily and seasonal load profiles. This leads to the increased ability of utilities to exploit metering data for power quality analysis purposes. This paper examines the scope for, and challenges associated with, …


Putting The Architecting Back Into Software Architecture With Systems Thinking Agent-Based Modelling, Trevor Harrison, Allan Peter Campbell, Thong Nguyen Jan 2010

Putting The Architecting Back Into Software Architecture With Systems Thinking Agent-Based Modelling, Trevor Harrison, Allan Peter Campbell, Thong Nguyen

SMART Infrastructure Facility - Papers

This paper details exploratory research which treats architecting as a system. This human architecting system has a structure composed of decisions, interdependencies amongst decisions, decision making, decision makers and the decision-making environment. Agent-based modelling is used to model the architecting system, and simulation is used to visualise system behaviour over time. The goal is to map legitimate / optimal speed of architectural decision-making to an architecting system behaviour pattern. Knowing the appropriate behaviour pattern of early architecture evolution will provide a mechanism for fine-grained progress tracking of architectural design. Divergence from this behaviour pattern should provide early warning signs of …


Some Complex Systems Engineering Principles, Matthew J. Berryman, Peter Campbell Jan 2010

Some Complex Systems Engineering Principles, Matthew J. Berryman, Peter Campbell

SMART Infrastructure Facility - Papers

Complex adaptive systems can be characterised by many adaptively changing parts, with a large number of interactions, and adaptation at the system level. This body of research can inform the large engineering projects that are characterised by large systems of systems, where interactions to achieve end goals matters, and where designs and the technology of parts in service undergo many adaptive changes. A number of key lessons can be drawn from the complex adaptive systems literature. Firstly, that the use of design patterns, as traditionally applied in software engineering, can also be applied to wider systems engineering and systems integration …


Genetic Structure And Dispersal Patterns Of The Invasive Psocid Liposcelis Decolor (Pearman) In Australian Grain Storage Systems, Katarina Maryann Mikac, N N. Fitzsimmons Jan 2010

Genetic Structure And Dispersal Patterns Of The Invasive Psocid Liposcelis Decolor (Pearman) In Australian Grain Storage Systems, Katarina Maryann Mikac, N N. Fitzsimmons

Faculty of Science - Papers (Archive)

Microsatellite markers were used to investigate the genetic structure among invasive L. decolor populations from Australia and a single international population from Kansas, USA to determine patterns of dispersal. Six variable microsatellites displayed an average of 2.5-4.2 alleles per locus per population. Observed (H-O) heterozygosity ranged from 0.12-0.65 per locus within populations; but, in 13 of 36 tests, H-O was less than expected. Despite low levels of allelic diversity, genetic structure estimated as theta was significant for all pairwise comparisons between populations (theta = 0.05-0.23). Due to suspected null alleles at four loci, ENA (excluding null alleles) corrected F-ST estimates …


Support Of Distribution System Using Distributed Wind And Pv Systems, Kai Zou, Ashish P. Agalgaonkar, Kashem Muttaqi, Sarath Perera, N Browne Jan 2009

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 …


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 Jan 2009

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

Faculty of Informatics - Papers (Archive)

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.


Development Of Non-Antibiotic-Resistant, Chromosomally Based, Constitutive And Inducible Expression Systems For Aroa-Attenuated Salmonella Enterica Serovar Typhimurium, Jake Matic, Tamsin D. Terry, David Van Bockel, Tracy A. Maddocks, David Tinworth, Michael Jennings, Steven P Djordjevic, Mark J. Walker Jan 2009

Development Of Non-Antibiotic-Resistant, Chromosomally Based, Constitutive And Inducible Expression Systems For Aroa-Attenuated Salmonella Enterica Serovar Typhimurium, Jake Matic, Tamsin D. Terry, David Van Bockel, Tracy A. Maddocks, David Tinworth, Michael Jennings, Steven P Djordjevic, Mark J. Walker

Faculty of Science - Papers (Archive)

Live-vaccine delivery systems expressing two model antigens from Mycoplasma hyopneumoniae, F2(P97) (Adh) and NrdF, were constructed using Salmonella enterica serovar Typhimurium aroA (STM-1), and immunogenicity in mice was evaluated. Recombinant plasmid-based expression (PBE) and chromosomally based expression (CBE) systems were constructed. The PBE system was formed by cloning both antigen genes into pJLA507 to create an operon downstream of temperature-inducible promoters. Constitutive CBE was achieved using a promoter-trapping technique whereby the promoterless operon was stably integrated into the chromosome of STM-1, and the expression of antigens was assessed. The chromosomal position of the operon was mapped in four clones. Inducible …


Control Of Energy Storage Interface With A Bidirectional Converter For Photovoltaic Systems, K.N Hasan, M.E Haque, Michael Negnevitsky, Kashem Muttaqi Jan 2008

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

Faculty of Informatics - Papers (Archive)

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 …


Optimisation Of Distributed Generation Units And Shunt Capacitors For Economic Operation Of Distribution Systems, Kai Zou, Sarath Perera, Kashem Muttaqi, Ashish P. Agalgaonkar Jan 2008

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

Faculty of Informatics - Papers (Archive)

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 Jan 2008

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

Faculty of Informatics - Papers (Archive)

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.


Embracing Social Uncertainties With Complex Systems Science, Pascal Perez Jan 2008

Embracing Social Uncertainties With Complex Systems Science, Pascal Perez

SMART Infrastructure Facility - Papers

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 …