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2012

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Articles 751 - 780 of 12196

Full-Text Articles in Physical Sciences and Mathematics

Embedded Partially Replicated Designs For Grain Quality Testing, Alison B. Smith, Robin Thompson, Brian R. Cullis Dec 2012

Embedded Partially Replicated Designs For Grain Quality Testing, Alison B. Smith, Robin Thompson, Brian R. Cullis

Dr Alison Smith

The literature on the design and analysis of cereal variety trials has focussed on the trait of grain yield. Such trials are also used to obtain information on grain quality traits but these are rarely subjected to the same level of statistical rigour. The data are often obtained using composite rather than individual replicate samples. This precludes the use of an efficient statistical analysis. In this paper we propose an approach in which a proportion of varieties is grain quality tested using individual replicate samples. This is achieved by embedding a partially replicated design (for measuring quality traits) within a …

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When Is The Cuntz-Krieger Algebra Of A Higher-Rank Graph Approximately Finite-Dimensional?, D Evans, Aidan Sims Dec 2012

When Is The Cuntz-Krieger Algebra Of A Higher-Rank Graph Approximately Finite-Dimensional?, D Evans, Aidan Sims

Professor Aidan Sims

We investigate the question: when is a higher-rank graph C*-algebra approximately finite-dimensional? We prove that the absence of an appropriate higher-rank analogue of a cycle is necessary. We show that it is not in general sufficient, but that it is sufficient for higher-rank graphs with finitely many vertices. We give a detailed description of the structure of the C*-algebra of a row-finite locally convex higher rank graph with finitely many vertices. Our results are also sufficient to establish that if the C*-algebra of a higher-rank graph is AF, then its every ideal must be gauge-invariant. We prove that for a …

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The Co-Universal C*-Algebra Of A Row-Finite Graph, Aidan Sims Dec 2012

The Co-Universal C*-Algebra Of A Row-Finite Graph, Aidan Sims

Professor Aidan Sims

Let $E$ be a row-finite directed graph. We prove that there exists a $C^*$-algebra $\Cr{E}$ with the following co-universal property: given any $C^*$-algebra $B$ generated by a Toeplitz-Cuntz-Krieger $E$-family in which all the vertex projections are nonzero, there is a canonical homomorphism from $B$ onto $\Cr{E}$. We also identify when a homomorphism from $B$ to $\Cr{E}$ obtained from the co-universal property is injective. When every loop in $E$ has an entrance, $\Cr{E}$ coincides with the graph $C^*$-algebra $C^*(E)$, but in general, $\Cr{E}$ is a quotient of $C^*(E)$. We investigate the properties of $\Cr{E}$ with emphasis on the utility of co-universality …

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Crossed Products Of K-Graph C*-Algebras By Zl, Cyntyhia Farthing, David Pask, Aidan Sims Dec 2012

Crossed Products Of K-Graph C*-Algebras By Zl, Cyntyhia Farthing, David Pask, Aidan Sims

Professor Aidan Sims

An action of Zl by automorphisms of a k-graph induces an action of Zl by automorphisms of the corresponding k-graph C*-algebra. We show how to construct a (k + l)-graph whose C*-algebra coincides with the crossed product of the original k-graph C)-algebra by Zl. We then investigate the structure of the crossed-product C*-algebra.

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Renault's Equivalence Theorem For Reduced Groupoid C*-Algebras, Aidan Sims, Dana Williams Dec 2012

Renault's Equivalence Theorem For Reduced Groupoid C*-Algebras, Aidan Sims, Dana Williams

Professor Aidan Sims

We use the technology of linking groupoids to show that equivalent groupoids have Morita equivalent reduced C*-algebras. This equivalence is compatible in a natural way in with the Equivalence Theorem for full groupoid C*-algebras.

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Simplicity Of C*-Algebras Associated To Row-Finite Locally Convex Higher-Rank Graphs, David Robertson, Aidan Sims Dec 2012

Simplicity Of C*-Algebras Associated To Row-Finite Locally Convex Higher-Rank Graphs, David Robertson, Aidan Sims

Professor Aidan Sims

In a previous work, the authors showed that the C*-algebra C*(\Lambda) of a row-finite higher-rank graph \Lambda with no sources is simple if and only if \Lambda is both cofinal and aperiodic. In this paper, we generalise this result to row-finite higher-rank graphs which are locally convex (but may contain sources). Our main tool is Farthing's "removing sources" construction which embeds a row-finite locally convex higher-rank graph in a row-finite higher-rank graph with no sources in such a way that the associated C*-algebras are Morita equivalent.

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A Dixmier-Douady Theorem For Fell Algebras, Astrid An Huef, Alexander Kumjian, Aidan Sims Dec 2012

A Dixmier-Douady Theorem For Fell Algebras, Astrid An Huef, Alexander Kumjian, Aidan Sims

Professor Aidan Sims

We generalise the Dixmier–Douady classification of continuous-trace C*-algebras to Fell algebras. To do so, we show that C*-diagonals in Fell algebras are precisely abelian subalgebras with the extension property, and use this to prove that every Fell algebra is Morita equivalent to one containing a diagonal subalgebra. We then use the machinery of twisted groupoid C*-algebras and equivariant sheaf cohomology to define an analogue of the Dixmier–Douady invariant for Fell algebras, and to prove our classification theorem.

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A Direct Approach To Co-Universal Algebras Associated To Directed Graphs, Aidan Sims, S B. Webster Dec 2012

A Direct Approach To Co-Universal Algebras Associated To Directed Graphs, Aidan Sims, S B. Webster

Professor Aidan Sims

We prove directly that if $E$ is a directed graph in which every cycle has an entrance, then there exists a $C^*$-algebra which is co-universal for Toeplitz-Cuntz-Krieger $E$-families. In particular, our proof does not invoke ideal-structure theory for graph algebras, nor does it involve use of the gauge action or its fixed point algebra.

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Aperiodicity And Cofinality For Finitely Aligned Higher-Rank Graphs, Peter Lewin, Aidan Sims Dec 2012

Aperiodicity And Cofinality For Finitely Aligned Higher-Rank Graphs, Peter Lewin, Aidan Sims

Professor Aidan Sims

We introduce new formulations of aperiodicity and cofinality for finitely aligned higher-rank graphs $\Lambda$, and prove that $C^*(\Lambda)$ is simple if and only if $\Lambda$ is aperiodic and cofinal. The main advantage of our versions of aperiodicity and cofinality over existing ones is that ours are stated in terms of finite paths. To prove our main result, we first characterise each of aperiodicity and cofinality of $\Lambda$ in terms of the ideal structure of $C^*(\Lambda)$. In an appendix we show how our new cofinality condition simplifies in a number of special cases which have been treated previously in the literature; …

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Homology For Higher-Rank Graphs And Twisted C*-Algebras, Alex Kumjian, David Pask, Aidan Sims Dec 2012

Homology For Higher-Rank Graphs And Twisted C*-Algebras, Alex Kumjian, David Pask, Aidan Sims

Professor Aidan Sims

We introduce a homology theory for k-graphs and explore its fundamental properties. We establish connections with algebraic topology by showing that the homology of a k-graph coincides with the homology of its topological realisation as described by Kaliszewski et al. We exhibit combinatorial versions of a number of standard topological constructions, and show that they are compatible, from a homological point of view, with their topological counterparts. We show how to twist the C*-algebra of a k-graph by a T-valued 2-cocycle and demonstrate that examples include all noncommutative tori. In the appendices, we construct a cubical set Q(Λ) from a …

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Investigating The Impact Of Sensory Effects On The Quality Of Experience And Emotional Response In Web Videos, Benjamin Rainer, Markus Waltl, Eva Cheng, Muawiyath Shujau, Christian Timmerer, Stephen Davis, Ian Burnett, Christian Ritz, Hermann Hellwagner Dec 2012

Investigating The Impact Of Sensory Effects On The Quality Of Experience And Emotional Response In Web Videos, Benjamin Rainer, Markus Waltl, Eva Cheng, Muawiyath Shujau, Christian Timmerer, Stephen Davis, Ian Burnett, Christian Ritz, Hermann Hellwagner

Dr Muawiyath Shujau

Multimedia is ubiquitously available online with large amounts of video increasingly consumed through Web sites such as YouTube or Google Video. However, online multimedia typically limits users to visual/auditory stimulus, with onscreen visual media accompanied by audio. The recent introduction of MPEG-V proposed multi-sensory user experiences in multimedia environments, such as enriching video content with so-called sensory effects like wind, vibration, light, etc. In MPEG-V, these sensory effects are represented as Sensory Effect Metadata (SEM), which is additionally associated to the multimedia content. This paper presents three user studies that utilize the sensory effects framework of MPEG-V, investigating the emotional …

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Backward Compatible Spatialized Teleconferencing Based On Squeezed Recordings, Christian Ritz, Muawiyath Shujau, Xiguang Zheng, Bin Cheng, Eva Cheng, Ian Burnett Dec 2012

Backward Compatible Spatialized Teleconferencing Based On Squeezed Recordings, Christian Ritz, Muawiyath Shujau, Xiguang Zheng, Bin Cheng, Eva Cheng, Ian Burnett

Dr Muawiyath Shujau

No abstract provided.

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Spatial Filter Approach To Evaluating The Role Of Convection On The Evolution Of A Mesoscale Vortex, Glenn A. Creighton, Robert E. Hart, Philip Cunningham Dec 2012

Spatial Filter Approach To Evaluating The Role Of Convection On The Evolution Of A Mesoscale Vortex, Glenn A. Creighton, Robert E. Hart, Philip Cunningham

Department of Earth and Atmospheric Sciences: Faculty Publications

A new spatial filter is proposed that exploits a spectral gap in power between the convective scale and the system (‘‘vortex’’) scale during tropical cyclone (TC) genesis simulations. Using this spatial separation, this study analyzes idealized three-dimensional numerical simulations of deep moist convection in the presence of a symmetric midlevel vortex to quantify and understand the energy cascade between the objectively defined convective scale and system scale during the early stages of tropical cyclogenesis. The simulations neglect surface momentum, heat, and moisture fluxes to focus on generation and enhancement of vorticity within the interior to more completely close off the …

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U.S. Drought Monitor, December 4, 2012, Rich Tinker Dec 2012

U.S. Drought Monitor, December 4, 2012, Rich Tinker

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for December 4, 2012 (12/4/12) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Hay, Cattle, Winter wheat.

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First Temperature Observations With The Usu Very Large Rayleigh Lidar: An Examination Of Mesopause Temperatures, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Marcus J. Bingham, Lance W. Petersen, Matthew T. Emerick Dec 2012

First Temperature Observations With The Usu Very Large Rayleigh Lidar: An Examination Of Mesopause Temperatures, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Marcus J. Bingham, Lance W. Petersen, Matthew T. Emerick

Leda Sox

No abstract provided.

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Eavesdropping On The Smart Grid, Craig Valli, Andrew Woodward, Clinton Carpene, Peter Hannay, Murray Brand, Reino Karvinen, Christopher Holme Dec 2012

Eavesdropping On The Smart Grid, Craig Valli, Andrew Woodward, Clinton Carpene, Peter Hannay, Murray Brand, Reino Karvinen, Christopher Holme

Australian Digital Forensics Conference

An in-situ deployment of smart grid technology, from meters through to access points and wider grid connectivity, was examined. The aim of the research was to determine what vulnerabilities were inherent in this deployment, and what other consideration issues may have led to further vulnerability in the system. It was determined that there were numerous vulnerabilities embedded in both hardware and software and that configuration issues further compounded these vulnerabilities. The cyber threat against critical infrastructure has been public knowledge for several years, and with increasing awareness, attention and resource being devoted to protecting critical in the structure, it is …

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Weak Values Are Universal In Von Neumann Measurements, Justin Dressel, Andrew N. Jordan Dec 2012

Weak Values Are Universal In Von Neumann Measurements, Justin Dressel, Andrew N. Jordan

Mathematics, Physics, and Computer Science Faculty Articles and Research

We refute the widely held belief that the quantum weak value necessarily pertains to weak measurements. To accomplish this, we use the transverse position of a beam as the detector for the conditioned von Neumann measurement of a system observable. For any coupling strength, any initial states, and any choice of conditioning, the averages of the detector position and momentum are completely described by the real parts of three generalized weak values in the joint Hilbert space. Higher-order detector moments also have similar weak value expansions. Using the Wigner distribution of the initial detector state, we find compact expressions for …

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2012 Fall Engr333 Student Seminar Presentation, 2012 Fall Engr333 Dec 2012

2012 Fall Engr333 Student Seminar Presentation, 2012 Fall Engr333

ENGR 333

File for student presentation, given by students in the Fall 2012 class of ENGR333.

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Spectroscopy Of 88Y By The (P,Dγ) Reaction, T. J. Ross, C. W. Beausang, R. O. Hughes, N. D. Scielzo, J. T. Burke, J. M. Allmond, C. Angell, M. S. Basunia, D. L. Bleuel, R. J. Casperson, J. Escher, P. Fallon, R. Hatarik, J. Munson, S. Paschalis, M. Petri, L. Phair, J. J. Ressler Dec 2012

Spectroscopy Of 88Y By The (P,Dγ) Reaction, T. J. Ross, C. W. Beausang, R. O. Hughes, N. D. Scielzo, J. T. Burke, J. M. Allmond, C. Angell, M. S. Basunia, D. L. Bleuel, R. J. Casperson, J. Escher, P. Fallon, R. Hatarik, J. Munson, S. Paschalis, M. Petri, L. Phair, J. J. Ressler

Physics Faculty Publications

Low-spin, high-excitation energy states in 88Y have been studied using the 89Y(p,dγ) reaction. For this experiment a 25 MeV proton beam was incident upon a monoisotopic 89Y target. A silicon telescope array was used to detect deuterons, and coincident γ rays were detected using a germanium clover array. Most of the known low-excitation-energy low-spin states populated strongly via the (p,d) reaction mechanism are confirmed. Two states are seen for the first time and seven new transitions, including one which bypasses the two low-lying isomeric states, are observed.

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Acid-Base Catalysis In Proton-Coupled Electron Transfer Reactions (Pcet): The Effects Of Brönsted Bases On The Oxidation Of Glutathione And Hydroquinone, Ramos Jonnathan Medina Dec 2012

Acid-Base Catalysis In Proton-Coupled Electron Transfer Reactions (Pcet): The Effects Of Brönsted Bases On The Oxidation Of Glutathione And Hydroquinone, Ramos Jonnathan Medina

Theses and Dissertations

This thesis presents the results and discussion of the investigation of the effects of Brönsted bases on the kinetics and thermodynamics of two proton-coupled electron transfer processes: the mediated oxidation of glutathione and the electrochemical oxidation of hydroquinone. Proton-coupled electron transfer (PCET) is the name given to reactions that involve the transfer of electron(s) accompanied by the exchange of proton(s). PCETs are found in many chemical and biological processes, some of current technological relevance such as the oxygen reduction reaction in fuel cells, which involves the transfer of four electrons and four protons (4e-, 4H+); or the splitting of water …

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Enhanced Learner Model For Adaptive Mobile Learning, Ahmed Alhmouz, Jun Shen, Jun Yan, Rami Al-Hmouz Dec 2012

Enhanced Learner Model For Adaptive Mobile Learning, Ahmed Alhmouz, Jun Shen, Jun Yan, Rami Al-Hmouz

Dr Jun Shen

Personalisation and learner modelling are becoming more important in the area of mobile learning applications, taking into consideration learners' interests, preferences and contextual information. Students nowadays are able to learn anywhere and at any time. Mobile learning application content is one of several factors within various contexts that play an important role in the success of the adaptation process. The vast amount of data involved in any successful adaptation process creates complexity and poses serious challenges. This paper focuses on how to model the learner and all possible contexts in an extensible way that can be used for personalisation in …

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Towards Knowledge Management In Sports Event Management: Context Analysis Of Malaysian Biannual Games With Commonkads, Azizul Abdul Ghaffar, Ghassan Beydoun, Jun Shen, William Tibben Dec 2012

Towards Knowledge Management In Sports Event Management: Context Analysis Of Malaysian Biannual Games With Commonkads, Azizul Abdul Ghaffar, Ghassan Beydoun, Jun Shen, William Tibben

Dr Jun Shen

Context Analysis (CA) is typically used as an early phase preceding the development of a knowledge-based systems in order to indicate how the system should interact with its environment and the various stakeholders. We undertake a detailed context analysis of business processes of the Malaysian Games (MG)to highlight blind spots of the process and enable the identification of an initial sports event knowledge management (KM) framework. Firstly, our CommonKADS driven analysis highlights how we can improve the business process and enable the organization to develop, distribute and apply its knowledge resources effectively. Secondly, the paper highlights specific features about the …

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A Survey On Bio-Inspired Algorithms For Web Service Composition, Lijuan Wang, Jun Shen, Jianming Yong Dec 2012

A Survey On Bio-Inspired Algorithms For Web Service Composition, Lijuan Wang, Jun Shen, Jianming Yong

Dr Jun Shen

Web service composition has become a promis- ing technology in a variety of e-science or e-business areas. There are a variety of models and methods to deal with this issue from di#11;erent aspects. Bio-inspired algorithms are becoming main approaches and solutions. This paper reviews the current researches on web service composition based on bio-inspired algorithms, such as Ant Colony Opti- mization(ACO), Genetic Algorithm(GA), Evolutionary Al- gorithm(EA) and Particle Swarm Optimization(PSO). By analyzing and investigating di#11;erent approaches, this paper gives an overview about the researches on bio-inspired al- gorithm in web service composition and point out future directions.

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P2cp: A New Cloud Storage Model To Enhance Performance Of Cloud Services, Zhe Sun, Jun Shen, Ghassan Beydoun Dec 2012

P2cp: A New Cloud Storage Model To Enhance Performance Of Cloud Services, Zhe Sun, Jun Shen, Ghassan Beydoun

Dr Jun Shen

This paper presents a storage model named Peer to Cloud and Peer (P2CP). Assuming that the P2CP model follows the Poisson process or Little’s law, we prove that the speed and availability of P2CP is generally better than that of the pure Peer to Peer (P2P) model, the Peer to Server, Peer (P2SP) model or the cloud model. A key feature of our P2CP is that it has three data transmission tunnels: the cloud-user data transmission tunnel, the clients’ data transmission tunnel, and the common data transmission tunnel. P2CP uses the cloud storage system as a common storage system. When …

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Analysis Of Business Process Integration In Web Service Context, J. Shen, G. Grossmann, Y. Yang, M. Stumptner, M. Schrefl, T. Reiter Dec 2012

Analysis Of Business Process Integration In Web Service Context, J. Shen, G. Grossmann, Y. Yang, M. Stumptner, M. Schrefl, T. Reiter

Dr Jun Shen

The integration of Web services is a recent outgrowth of the Business Process integration field that will require powerful meta-schema matching mechanisms supported by higher level abstractions, such as UML meta-models. Currently, there are many XML-based workflow process specification languages (e.g. XPDL, BPEL) which can be used to define business processes in the Web services and Grid Computing world. However, with limited capability to describe the relationships (schemas or ontologies) between process objects, the dominant use of XML as a meta-data markup language makes the semantics of the processes ambiguous. OWL-S (Ontology Web Language for Services) exploits the semantic description …

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Towards Peer Selection In A Semantically-Enriched Service Execution Framework With Qos Specifications, Jun Shen, Ghassan Beydoun, Graham Low, Brian Henderson-Sellers, Shuai Yuan Dec 2012

Towards Peer Selection In A Semantically-Enriched Service Execution Framework With Qos Specifications, Jun Shen, Ghassan Beydoun, Graham Low, Brian Henderson-Sellers, Shuai Yuan

Dr Jun Shen

This paper promotes an ontology-based multi agent system (MAS) framework to facilitate Peer-to-Peer (P2P) service selection with multiple service properties. P2P-based service has emerged as an important new field in the distributed computing arena. It focuses on intensive service sharing, innovative applications and compositions, and, in some cases, high performance orientation. However, one of the remaining challenges for the P2P-based service composition process is how to effectively discover and select the most appropriate peers to execute the service applications when considering multiple properties of the requested services. By introducing an ontology, different ontology-based e-service profiles can be proposed to facilitate …

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Towards Bio-Inspired Cost Minimisation For Data-Intensive Service Provision, Lijuan Wang, Jun Shen Dec 2012

Towards Bio-Inspired Cost Minimisation For Data-Intensive Service Provision, Lijuan Wang, Jun Shen

Dr Jun Shen

The world is filled with an unimaginably vast amount of digital information which is getting even vaster and even growing more rapidly. The enormous new data is impacting every area of our society. The real strategic value of the data can determine what will happen and what can be discovered in the future. To better use the so called “Big Data”, automatic business process or workflow is needed to process large quantity of data. Biological systems present fascinating features, such as autonomy, scalability, adaptability, and robustness. The bio-inspired concepts and mechanisms have been successfully applied to service oriented systems. In …

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Evaluating Usage Of Wsmo And Owl-S In Semantic Web Services, Lina Azleny Kamaruddin, Jun Shen, Ghassan Beydoun Dec 2012

Evaluating Usage Of Wsmo And Owl-S In Semantic Web Services, Lina Azleny Kamaruddin, Jun Shen, Ghassan Beydoun

Dr Jun Shen

Applying ontologies is the most promising approach to semantically enrich Web services. To facilitate this, two efforts contributed the most in enabling the creation of ontologies: OWL-S from the US and WSMO in Europe. These two compete and promote their ontologies from the design perspective, reflecting their inventors’ bias but not offering much help to Web service developers using them. To bypass existing biases and enable evaluation of ontologies expressed in these two languages, this paper provides a study of the two important facilitators, OWL-S and WSMO, surveying their usage in several SWS Projects and identifying their respective and outstanding …

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A Pragmatic Gis-Oriented Ontology For Location Based Services, Jun Shen, Aneesh Krishna, Shuai Yuan, Ke Cai, Yuemin Qin Dec 2012

A Pragmatic Gis-Oriented Ontology For Location Based Services, Jun Shen, Aneesh Krishna, Shuai Yuan, Ke Cai, Yuemin Qin

Dr Jun Shen

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 …

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Reflecting On Ontologies Towards Ontology-Based Agent-Oriented Software Engineering, Ghassan Beydoun, Brian Henderson-Sellers, Jun Shen, G. Low Dec 2012

Reflecting On Ontologies Towards Ontology-Based Agent-Oriented Software Engineering, Ghassan Beydoun, Brian Henderson-Sellers, Jun Shen, G. Low

Dr Jun Shen

“Ontology” in association with “software engineering” is becoming commonplace. This paper argues for the need to place ontologies at the centre of the software development lifecycle for multi agent systems to enhance reuse of software workproducts as well as to unify agent-based software engineering knowledge. The paper bridges the state-of-the-art of ontologies research from Knowledge Engineering (KE) within Artificial Intelligence and Metamodelling within Software Engineering (SE). It presents a sketch of an ontology-based Multi Agent System (MAS) methodology discussing key roles on ontologies and their impact of workproducts, illustrating these in a MAS software development project for an important application …

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