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Full-Text Articles in Physical Sciences and Mathematics
Adaptive Task Allocation For P2p-Based E-Services Composition, Jun Shen, Shuai Yuan
Adaptive Task Allocation For P2p-Based E-Services Composition, Jun Shen, Shuai Yuan
Faculty of Informatics - Papers (Archive)
To effectively manage the task allocation, especially when handling with numerous different peers’ qualities, is one of the greatest challenges to be faced in order to guarantee the success of P2P-based e-services composition. In this context, various QoS descriptive frameworks and Web services technologies (such as WSDL and BPEL) are being considered as the most affordable solutions to promote the performance of decentralized e-services, through applying strategies like QoS ontologies and related optimization algorithms globally or locally. Nonetheless, most P2P-based service selection and composition approaches applied nowadays lack dynamism and autonomy. In this paper, we first propose an extension of …
Resource Price Turbulence And Macroeconomic Adjustment For A Resource Exporter: A Conceptual Framework For Policy Analysis, Grant M. Cox, Charles Harvie
Resource Price Turbulence And Macroeconomic Adjustment For A Resource Exporter: A Conceptual Framework For Policy Analysis, Grant M. Cox, Charles Harvie
Faculty of Informatics - Papers (Archive)
The increased demand for energy and other resources in global markets, particularly arising from therapidly developing economies of China and India, has resulted in considerable turbulence in resourceprices, and most obviously that of oil. The recent magnitude of change, both positive and negative, inresource prices and their macroeconomic implications is of considerable contemporary importance forboth resource importing and exporting economies. For a resource exporting economy, such as that ofAustralia, the resource price boom had a number of beneficial effects: increased government taxationrevenues, increased employment and higher wages in the resource and resource related sectors,increased spending in the domestic economy and …
Control Of Energy Storage Interface With A Bidirectional Converter For Photovoltaic Systems, K.N Hasan, M.E Haque, Michael Negnevitsky, Kashem Muttaqi
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 …
The Wii Remote As An Input Device For 3d Interaction In Immersive Head-Mounted Display Virtual Reality, Yang-Wai Chow
The Wii Remote As An Input Device For 3d Interaction In Immersive Head-Mounted Display Virtual Reality, Yang-Wai Chow
Faculty of Informatics - Papers (Archive)
There has been a lot of interest regarding the possibilities that the motion sensing technology in the Wii Remote can offer. This study investigates the feasibility of using the Wii Remote for 3D interaction in immersive Head-Mounted Display (HMD) virtual reality. Normal usage of the Wii Remote requires that the controller to be pointed in a certain direction, typically towards the display. The requirements of an input device for interaction in immersive HMD virtual reality differ from that of normal display systems, in that the user should ideally be able to turn around in the virtual environment. A number of …
Optimisation Of Distributed Generation Units And Shunt Capacitors For Economic Operation Of Distribution Systems, Kai Zou, Sarath Perera, Kashem Muttaqi, Ashish P. Agalgaonkar
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 …
A Pragmatic Gis-Oriented Ontology For Location Based Services, Jun Shen, Aneesh Krishna, Shuai Yuan, Ke Cai, Yuemin Qin
A Pragmatic Gis-Oriented Ontology For Location Based Services, Jun Shen, Aneesh Krishna, Shuai Yuan, Ke Cai, Yuemin Qin
Faculty of Informatics - Papers (Archive)
With advances in automatic position sensing and wireless connectivity, location-based services (LBS) are rapidly developing, particularly in fields of geographic, tourism and logistic information systems. Currently, Web service has been viewed as one of most significant innovations in business industry, and designed on demand to provide spatial related information for LBS consumption. However, the traditional Web Service Description Language (WSDL) cannot meet those requirements, as WSDL is not able to support semantic content and information. In recent years, Ontology came up with an effective approach to enhance service description, automated discovery, dynamic composition, enactment, and other tasks such as managing …
A Scalable Lightweight Distributed Crawler For Crawling With Limited Resources, Milly W. Kc, Markus Hagenbuchner, Ah Chung Tsoi
A Scalable Lightweight Distributed Crawler For Crawling With Limited Resources, Milly W. Kc, Markus Hagenbuchner, Ah Chung Tsoi
Faculty of Informatics - Papers (Archive)
Web page crawlers are an essential component in a number of Web applications. The sheer size of the Internet can pose problems in the design of Web crawlers. All currently known crawlers implement approximations or have limitations so as to maximize the throughput of the crawl, and hence, maximize the number of pages that can be retrieved within a given time frame. This paper proposes a distributed crawling concept which is designed to avoid approximations, to limit the network overhead, and to run on relatively inexpensive hardware. A set of experiments, and comparisons highlight the effectiveness of the proposed approach.
Modelling Of Hydraulic Governor-Turbine For Control Stabilisation, Michael Negnevitsky, Kashem Muttaqi, Yin Chin Choo
Modelling Of Hydraulic Governor-Turbine For Control Stabilisation, Michael Negnevitsky, Kashem Muttaqi, Yin Chin Choo
Faculty of Informatics - Papers (Archive)
Power system performance is affected by dynamic characteristics of hydraulic governor-turbines during and following any disturbance, such as occurrence of a fault, loss of a transmission line or a rapid change of load. Accurate modelling of hydraulic governor-turbines is essential to characterise and diagnose the system response during an emergency. In this article, both detailed and simplified hydraulic systems governed by proportional-integral-derivative and proportional-integral controllers are modelled. This article examines their transient responses to disturbances through simulation in Matlab/Simulink. The article also investigates the dynamic performance of an isolated hydraulic system through evaluating stability margins, eigenvalues, root loci and frequency …
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 …
Conditions For The Assessment Of The Harmonic Compliance Of An Installation, Timothy J. Browne, Sarath Perera, Victor J. Gosbell
Conditions For The Assessment Of The Harmonic Compliance Of An Installation, Timothy J. Browne, Sarath Perera, Victor J. Gosbell
Faculty of Informatics - Papers (Archive)
Methods of allocating harmonic emission limits to customer installations have evolved considerably, as evidenced by the development of harmonic guides such as IEEE-519 and IEC/TR 61000-3-6. However, there is only limited consensus on appropriate techniques validating compliance of installations with those limits. Existing techniques are reviewed and related problems are examined. Conditions which acceptable tests of compliance should meet are proposed.
Proposal For A New Class Of Materials: Spin Gapless Semiconductors, Xiaolin Wang
Proposal For A New Class Of Materials: Spin Gapless Semiconductors, Xiaolin Wang
Australian Institute for Innovative Materials - Papers
The concept of the spin gapless semiconductor in which both electron and hole can be fully spin polarized is proposed, and its possibility is presented on the basis of first-principles electronic structure calculations. Possible new physics and potential applications in spintronic devices based on the spin gapless semiconductors are discussed.
Flux-Pinning Mechanism In Silicone-Oil Doped Mgb2: Evidence For Charge-Carrier Mean Free Path Fluctuation Pinning, Shaban R. Ghorbani, Xiaolin Wang, S X. Dou, Sung-Ik Lee, Md S. Hossain
Flux-Pinning Mechanism In Silicone-Oil Doped Mgb2: Evidence For Charge-Carrier Mean Free Path Fluctuation Pinning, Shaban R. Ghorbani, Xiaolin Wang, S X. Dou, Sung-Ik Lee, Md S. Hossain
Australian Institute for Innovative Materials - Papers
Flux-pinning mechanism of MgB2 doped with 10 wt % silicone-oil sintered at low and high temperatures has been investigated by magnetic measurements. The field dependence of the critical current density, jc(B), was analysed within the collective pinning model. A crossover field, Bsb, from the single vortex to the small vortex bundle-pinning regime was observed. For both types of sintered samples, the temperature dependence of Bsb(T) at low temperature is in good agreement with the δl pinning mechanism, i.e., pinning associated with charge-carrier mean free path fluctuation. At temperatures close to the critical …
Inkjet Printing: A Viable Tool For Processing Polymer Carbon Nanotube Composites, Marc In Het Panhuis, William R. Small
Inkjet Printing: A Viable Tool For Processing Polymer Carbon Nanotube Composites, Marc In Het Panhuis, William R. Small
Faculty of Science - Papers (Archive)
The inkjet processing of water dispersable polymer carbon nanotube composite materials is reported. Single printed layers displayed good optical transparency, sheet resistance, and conductivity. It is demonstrated that an alcohol sensor based on a single printed layer of polymer carbon nanotube composite could operate at a lower voltage compared to a sensor based on a single printed layer of the polymer.
Integrated Late Quaternary Chronostratigraphy For San Salvador Island, Bahamas: Patterns And Trends Of Morphological Change In The Land Snail Cerion, Paul Hearty, Stephen A. Schellenberg
Integrated Late Quaternary Chronostratigraphy For San Salvador Island, Bahamas: Patterns And Trends Of Morphological Change In The Land Snail Cerion, Paul Hearty, Stephen A. Schellenberg
Faculty of Science - Papers (Archive)
Reconstructing the phylogeny and biogeography of the Caribbean land snail Cerion requires a robust stratigraphic and chronological framework. To this end, we have determined the stratigraphic succession on San Salvador, a Bahamian island with a rich fossil and modern Cerion fauna. A primary purpose of this paper is to independently verify this succession through whole-rock and Cerion aminostratigraphies and AMS 14C-based age models. Over 150 individual Cerion shells were age-ranked from 140 ka to modern using stratigraphic position and reverse-phase HPLC (RPC) amino acid racemization, which was sufficiently sensitive to resolve stratigraphic subunits within the Holocene and late Pleistocene. …
Elimination Of Gamma Nonlinear Luminance Effects For Digital Video Projection Phase Measuring Profilometers, Matthew J. Baker, Jiangtao Xi, Joe F. Chicharo
Elimination Of Gamma Nonlinear Luminance Effects For Digital Video Projection Phase Measuring Profilometers, Matthew J. Baker, Jiangtao Xi, Joe F. Chicharo
Faculty of Informatics - Papers (Archive)
In this paper we are concerned with the elimination of gamma related errors by employing a simple and direct approach, specifically, for phase measuring profilometry (PMP) methods. The harmonic structure of a gamma distorted fringe is investigated and the implications of j for the PMP algorithm is studied. The minimum requirements in terms of number of Steps for appropriate elimination of j related phase residuals is identified and verified via both simulation and practical experimentation.
Comparison Of Mass Spectrometry And Other Techniques For Probing Interactions Between Metal Complexes And Dna, Thitima Urathamakul, Daniel J. Waller, Jennifer L. Beck, Janice Aldrich-Wright, Stephen F. Ralph
Comparison Of Mass Spectrometry And Other Techniques For Probing Interactions Between Metal Complexes And Dna, Thitima Urathamakul, Daniel J. Waller, Jennifer L. Beck, Janice Aldrich-Wright, Stephen F. Ralph
Faculty of Science - Papers (Archive)
Electrospray ionization mass spectrometry (ESI-MS) was used to study the binding interactions of two series of ruthenium complexes, [Ru(phen)2L]2+ and [RuL′2(dpqC)]2+, to a double stranded DNA hexadecamer, and derive orders of relative binding affinity. These were shown to be in good agreement with orders of relative binding affinity derived from absorption and circular dichroism (CD) spectroscopic examination of the same systems and from DNA melting curves. However, the extent of luminescence enhancement caused by the addition of DNA to solutions of the ruthenium complexes showed little correlation with orders of binding affinity derived from ESI-MS or any of the other …
Reactions Of The Hydroperoxide Anion With Dimethyl Methylphosphonate In An Ion Trap Mass Spectrometer: Evidence For A Gas Phase A-Effect, Andrew M Mcanoy, Martin Paine, Stephen J. Blanksby
Reactions Of The Hydroperoxide Anion With Dimethyl Methylphosphonate In An Ion Trap Mass Spectrometer: Evidence For A Gas Phase A-Effect, Andrew M Mcanoy, Martin Paine, Stephen J. Blanksby
Faculty of Science - Papers (Archive)
The gas phase degradation reactions of the chemical warfare agent (CWA) simulant, dimethyl methylphosphonate (DMMP), with the hydroperoxide anion (HOO–) were investigated using a modified quadrupole ion trap mass spectrometer. The HOO– anion reacts readily with neutral DMMP forming two significant product ions at m/z 109 and m/z 123. The major reaction pathways correspond to (i) the nucleophilic substitution at carbon to form [CH3P(O)(OCH3)O]– (m/z 109) in a highly exothermic process and (ii) exothermic proton transfer. The branching ratios of the two reaction pathways, 89% and 11% respectively, indicate that the …
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 …
An Energy-Aware Multilevel Clustering Algorithm For Wireless Sensor Networks, Xinfang Yan, Jiangtao Xi, Joe F. Chicharo, Yanguang Yu
An Energy-Aware Multilevel Clustering Algorithm For Wireless Sensor Networks, Xinfang Yan, Jiangtao Xi, Joe F. Chicharo, Yanguang Yu
Faculty of Informatics - Papers (Archive)
Clustering sensors nodes as the basic of routing is an efficient mechanism for prolonging the lifetime of wireless sensor networks. In this paper, the high-efficient multilevel clustering is abstracted as a root tree which has the performances of the minimal relay set and the maximal weight according to graph theory. A mathematical model for the clustering virtual backbone is built. Based on the model, an algorithm called energy-aware multilevel clustering (EAMC) is proposed. The EAMC can reduce the number of relays used for data transmission by minimizing the amount of the nodes in the root tree (that is cluster-head). Furthermore, …
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 …