48 results for Cranefield, Stephen, Working or discussion paper

  • Bridging the gap between the Model-Driven Architecture and ontology engineering

    Cranefield, Stephen; Pan, Jin (2005-12)

    Working or discussion paper
    University of Otago

    Please note that there is a revised version of this paper available at http://hdl.handle.net/10523/1260 (currently in press with the International Journal of Human-Computer Studies).

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  • Role model based mechanism for norm emergence in artificial agent societies

    Savarimuthu, Bastin Tony Roy; Cranefield, Stephen; Purvis, Martin; Purvis, Maryam A. (2007-07)

    Working or discussion paper
    University of Otago

    A revised version of this paper appears in the Proceedings of the AAMAS'07 Workshop on Coordination, Organization, Institutions and Norms in Agent Systems (COIN), Honolulu, Hawaii, USA, 14th May, pp. 1-12. See http://www.ia.urjc.es/COIN2007/ for further details.

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  • UML and the Semantic Web

    Cranefield, Stephen (2001-02)

    Working or discussion paper
    University of Otago

    This paper discusses technology to support the use of UML for representing ontologies and domain knowledge in the Semantic Web. Two mappings have been defined and implemented using XSLT to produce Java classes and an RDF schema from an ontology represented as a UML class diagram and encoded using XMI. A Java application can encode domain knowledge as an object diagram realised as a network of instances of the generated classes. Support is provided for marshalling and unmarshalling this object-oriented knowledge to and from an RDF/XML serialisation.

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  • Communicative acts and interaction protocols in a distributed information system

    Nowostawski, Mariusz; Carter, Dan; Cranefield, Stephen; Purvis, Martin (2003-05)

    Working or discussion paper
    University of Otago

    In FIPA-style multi-agent systems, agents coordinate their activities by sending messages representing particular communicative acts (or performatives). Agent communication languages must strike a balance between simplicity and expressiveness by defining a limited set of communicative act types that fit the communication needs of a wide set of problems. More complex requirements for particular problems must then be handled by defining domain-specific predicates and actions within ontologies. This paper examines the communication needs of a multi-agent distributed information retrieval system and discusses how well these are met by the FIPA ACL.

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  • Embedding agents in business applications using enterprise integration patterns

    Cranefield, Stephen; Ranathunga, Surangika (2013-02-08)

    Working or discussion paper
    University of Otago

    This paper addresses the issue of integrating agents with a variety of external resources and services, as found in enterprise computing environments. We propose an approach for interfacing agents and existing message routing and mediation engines based on the endpoint concept from the enterprise integration patterns of Hohpe and Woolf. A design for agent endpoints is presented, and an architecture for connecting the Jason agent platform to the Apache Camel enterprise integration framework using this type of endpoint is described. The approach is illustrated by means of a business process use case, and a number of Camel routes are presented. These demonstrate the benefits of interfacing agents to external services via a specialised message routing tool that supports enterprise integration patterns.

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  • View-based consistency and its implementation

    Huang, Zhiyi; Sun, Chengzheng; Cranefield, Stephen; Purvis, Martin (2001-05)

    Working or discussion paper
    University of Otago

    This paper proposes a novel View-based Consistency model for Distributed Shared Memory. A view is a set of ordinary data objects that a processor has the right to access in a data-race-free program. The View-based Consistency model only requires that the data objects of a view are updated before a processor accesses them. Compared with other memory consistency models, the View-based Consistency model can achieve data selection without user annotation and can reduce much false-sharing effect. This model has been implemented based on TreadMarks. Performance results have shown that for all our applications the View-based Consistency model outperforms the Lazy Release Consistency model.

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  • Integrating expectation handling into Jason

    Ranathunga, Surangika; Cranefield, Stephen; Purvis, Martin (2011-02)

    Working or discussion paper
    University of Otago

    Although expectations play an important role in designing cognitive agents, agent expectations are not explicitly being handled in most common agent programming environments. There are techniques for monitoring fulfilment and violation of agent expectations, however they are not linked with common agent programming environments so that agents can be easily programmed to respond to these circumstances. This paper investigates how expectation monitoring tools can be tightly integrated with the Jason BDI agent interpreter by extending it with built-in actions to initiate and terminate monitoring of expectations, and demonstrates how an external expectation monitor is linked with Jason using these internal actions.

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  • Automating information processing tasks: an agent-based architecture

    Cranefield, Stephen; McKinlay, Bryce; Moreale, Emanuela; Purvis, Martin (1998-03)

    Working or discussion paper
    University of Otago

    This paper describes an agent-based architecture designed to provide automation support for users who perform information processing tasks using a collection of distributed and disparate software tools and on-line resources. The architecture extends previous work on agent-based software interoperability. The unique features of the information processing domain compared to distributed information retrieval are discussed and a novel extension of hierarchical task network (HTN) planning to support this domain is presented.

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  • A rule language for modelling and monitoring social expectations in multi-agent systems

    Cranefield, Stephen (2005-02)

    Working or discussion paper
    University of Otago

    This paper proposes a rule language for defining social expectations based on a metric interval temporal logic with past and future modalities and a current time binding operator. An algorithm for run-time monitoring compliance of rules in this language based on formula progression is also presented.

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  • On the testability of BDI agent systems

    Winikoff, Michael; Cranefield, Stephen (2008-11)

    Working or discussion paper
    University of Otago

    Before deploying a software system we need to assure ourselves (and stake-holders) that the system will behave correctly. This assurance is usually done by testing the system. However, it is intuitively obvious that adaptive systems, including agent-based systems, can exhibit complex behaviour, and are thus harder to test. In this paper we examine this “obvious intuition” in the case of Belief-Desire-Intention (BDI) agents. We analyse the size of the behaviour space of BDI agents and show that although the intuition is correct, the factors that influence the size are not what we expected them to be; specifically, we found that the introduction of failure handling had a much larger effect on the size of the behaviour space than we expected. We also discuss the implications of these findings on the testability of BDI agents.

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  • A study on feature analysis for musical instrument classification

    Deng, Da; Simmermacher, Christian; Cranefield, Stephen (2007-08)

    Working or discussion paper
    University of Otago

    In tackling data mining and pattern recognition tasks, finding a compact but effective set of features has often been found to be a crucial step in the overall problem-solving process. In this paper we present an empirical study on feature analysis for classical instrument recognition, using machine learning techniques to select and evaluate features extracted from a number of different feature schemes. It is revealed that there is significant redundancy between and within feature schemes commonly used in practice. Our results suggest that further feature analysis research is necessary in order to optimize feature selection and achieve better results for the instrument recognition problem.

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  • Generating ontology-specific content languages

    Cranefield, Stephen; Purvis, Martin (2001-05)

    Working or discussion paper
    University of Otago

    This paper examines a recent trend amongst software agent application and platform developers to desire the ability to send domain-specific objects within inter-agent messages. If this feature is to be supported without departing from the notion that agents communicate in terms of knowledge, it is important that the meaning of such objects be well understood. Using an object-oriented metamodelling approach, the relationships between ontologies and agent communication and content languages in FIPA-style agent systems are examined. It is shown how object structures in messages can be considered as expressions in ontology-specific extensions of standard content languages. It is also argued that ontologies must distingish between objects with and objects without identity.

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  • Reliable group communication and institutional actions in a multi-agent trading scenario

    Cranefield, Stephen (2004-12)

    Working or discussion paper
    University of Otago

    The use of asynchronous communication is traditionally seen to be an important element of an agent’s autonomy. This paper argues that groups of agents within a society need the ability to choose forms of communication with stronger guarantees for particular interactions, and in particular, focuses on the use of reliable group communication. An example electronic trading scenario — the game of Pit — is presented, and it is shown how a formal institution for a particular critical phase of Pit can be built on top of the semantics for totally ordered and virtually synchronous multicasting.

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  • Agent modelling with Petri nets

    Purvis, Martin; Cranefield, Stephen (1996-03)

    Working or discussion paper
    University of Otago

    The use of intelligent software agents is a modelling paradigm that is gaining increasing attention in the applications of distributed systems. This paper identifies essential characteristics of agents and shows how they can be mapped into a coloured Petri net representation so that the coordination of activities both within agents and between interacting agents can be visualised and analysed. The detailed structure and behaviour of an individual agent in terms of coloured Petri nets is presented, as well as a description of how such agents interact. A key notion is that the essential functional components of an agent are explicitly represented by means of coloured Petri net constructs in this representation.

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  • Integrating environmental information: Incorporating metadata in a distributed information systems architecture

    Cranefield, Stephen; Purvis, Martin (2000-02)

    Working or discussion paper
    University of Otago

    An approach is presented for incorporating metatata constraints into queries to be processed by a distributed environmental information system. The approach, based on a novel metamodel unifying concepts from the Unified Modelling Language (UML), the Object Query Language (OQL), and the Resource Description Framework (RDF), allows metadata information to be represented and processed in combination with regular data queries.

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  • An architecture for self-organising evolvable virtual machines

    Nowostawski, Mariusz; Purvis, Martin; Cranefield, Stephen (2004-11)

    Working or discussion paper
    University of Otago

    Contemporary software systems are exposed to demanding, dynamic, and unpredictable environments where the traditional adaptability mechanisms may not be sufficient. To imitate and fully benefit from life-like adaptability in software systems, that might come closer to the complexity levels of biological organisms, we seek a formal mathematical model of certain fundamental concepts such as: life, organism, evolvability and adaptation. In this work we will concentrate on the concept of software evolvability. Our work proposes an evolutionary computation model, based on the theory of hypercycles and autopoiesis. The intrinsic properties of hypercycles allow them to evolve into higher levels of complexity, analogous to multi-level, or hierarchical evolutionary processes. We aim to obtain structures of self-maintaining ensembles, that are hierarchically organised, and our primary focus is on such open-ended hierarchically organised evolution.

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  • The NZDIS project: An agent-based distributed information systems architecture

    Purvis, Martin; Cranefield, Stephen; Bush, Geoff; Carter, Dan; McKinlay, Bryce; Nowostawski, Mariusz; Ward, Roy (1999-08)

    Working or discussion paper
    University of Otago

    This paper describes an architecture for building distributed information systems from existing information resources, based on distributed object and software agent technologies. This architecture is being developed as part of the New Zealand Distributed Information Systems (NZDIS) project. An agent-based architecture is used: information sources are encapsulated as information agents that accept messages in an agent communication language (the FIPA ACL). A user agent assists users to browse ontologies appropriate to their domain of interest and to construct queries based on terms from one or more ontologies. One or more query processing agents are then responsible for discovering (from a resource broker agent) which data source agents are relevant to the query, decomposing the query into subqueries suitable for those agents (including the translation of the query into the specific ontologies implemented by those agents), executing the subqueries and translating and combining the subquery results into the desired result set. Novel features of this system include the use of standards from the object-oriented community such as the Common Object Request Broker Architecture (CORBA) (as a communications infrastructure), the Unified Modeling Language (used as an ontology representation language), the Object Data Management Group's Object Query Language (used for queries) and the Object Management Group's Meta Object Facility (used as the basis for an ontology repository agent). Query results need not be returned within an ACL message, but may instead be represented by a CORBA object reference which may be used to obtain the result set.

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  • Norm identification in multi-agent societies

    Savarimuthu, Bastin Tony Roy; Cranefield, Stephen; Purvis, Maryam A.; Purvis, Martin K. (2010-02)

    Working or discussion paper
    University of Otago

    In normative multi-agent systems, the question of “how an agent identifies a norm in an agent society” has not received much attention. This paper aims at addressing this question. To this end, this paper proposes an architecture for norm identification for an agent. The architecture is based on observation of interactions between agents. This architecture enables an autonomous agent to identify the norms in a society using the Candidate Norm Inference (CNI) algorithm. The CNI algorithm uses association rule mining approach to identify sequences of events as candidate norms. When a norm changes, the agent using our architecture will be able to modify the norm and also remove a norm if it does not hold in its society. Using simulations we demonstrate how an agent makes use of the norm identification framework.

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  • Verifying social expectations by model checking truncated paths

    Cranefield, Stephen; Winikoff, Michael (2007-12)

    Working or discussion paper
    University of Otago

    One approach to moderating the behaviour of agents in open societies is the use of explicit languages for defining norms, conditional commitments and/or social expectations, together with infrastructure supporting conformance checking and the identification and possible punishment of anti-social agents. This paper presents a logical account of the creation, fulfilment and violation of social expectations modelled as conditional rules over a hybrid propositional temporal logic. The semantics are designed to allow model checking over finite histories to be used to check for fulfilment and violation of expectations in both online and offline modes. For online checking, expectations are always considered at the last state in the history, but in the offline mode expectations in previous states are also checked. At each past state, the then active expectations must be checked for fulfilment without recourse to information from later states: the truth of a future-oriented temporal proposition φ at state s over the full history does not imply the fulfilment at s of an expectation with content φ. This issue is addressed by defining fulfilment and violation in terms of an extension of Eisner et al.’s weak/strong semantics for LTL over truncated paths. The update of expectations from one state to the next is based on formula progression and the approach has been implemented by extending the MCLITE and MCFULL algorithms of the Hybrid Logic Model Checker.

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  • A distributed architecture for environmental information systems

    Purvis, Martin; Cranefield, Stephen; Nowostawski, Mariusz (1999-04)

    Working or discussion paper
    University of Otago

    The increasing availability and variety of large environmental data sets is opening new opportunities for data mining and useful cross-referencing of disparate environmental data sets distributed over a network. In order to take advantage of these opportunities, environmental information systems will need to operate effectively in a distributed, open environment. In this paper, we describe the New Zealand Distributed Information System (NZDIS) software architecture for environmental information systems. In order to optimise extensibility, openness, and flexible query processing, the architecture is organised into collaborating software agents that communicate by means of a standard declarative agent communication language. The metadata of environmental data sources are stored as part of agent ontologies, which represent information models of the domain of the data repository. The agents and the associated ontological framework are designed as much as possible to take advantage of standard object-oriented technology, such as CORBA, UML, and OQL, in order to enhance the openness and accessibility of the system.

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