13,280 research outputs found

    KLAIM: A Kernel Language for Agents Interaction and Mobility

    Get PDF
    We investigate the issue of designing a kernel programming language for mobile computing and describe KLAIM, a language that supports a programming paradigm where processes, like data, can be moved from one computing environment to another. The language consists of a core Linda with multiple tuple spaces and of a set of operators for building processes. KLAIM naturally supports programming with explicit localities. Localities are first-class data (they can be manipulated like any other data), but the language provides coordination mechanisms to control the interaction protocols among located processes. The formal operational semantics is useful for discussing the design of the language and provides guidelines for implementations. KLAIM is equipped with a type system that statically checks access rights violations of mobile agents. Types are used to describe the intentions (read, write, execute, etc.) of processes in relation to the various localities. The type system is used to determine the operations that processes want to perform at each locality, and to check whether they comply with the declared intentions and whether they have the necessary rights to perform the intended operations at the specific localities. Via a series of examples, we show that many mobile code programming paradigms can be naturally implemented in our kernel language. We also present a prototype implementaton of KLAIM in Java

    A principled information valuation for communications during multi-agent coordination

    No full text
    Decentralised coordination in multi-agent systems is typically achieved using communication. However, in many cases, communication is expensive to utilise because there is limited bandwidth, it may be dangerous to communicate, or communication may simply be unavailable at times. In this context, we argue for a rational approach to communication --- if it has a cost, the agents should be able to calculate a value of communicating. By doing this, the agents can balance the need to communicate with the cost of doing so. In this research, we present a novel model of rational communication that uses information theory to value communications, and employ this valuation in a decision theoretic coordination mechanism. A preliminary empirical evaluation of the benefits of this approach is presented in the context of the RoboCupRescue simulator

    Advanced Knowledge Technologies at the Midterm: Tools and Methods for the Semantic Web

    Get PDF
    The University of Edinburgh and research sponsors are authorised to reproduce and distribute reprints and on-line copies for their purposes notwithstanding any copyright annotation hereon. The views and conclusions contained herein are the author’s and shouldn’t be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of other parties.In a celebrated essay on the new electronic media, Marshall McLuhan wrote in 1962:Our private senses are not closed systems but are endlessly translated into each other in that experience which we call consciousness. Our extended senses, tools, technologies, through the ages, have been closed systems incapable of interplay or collective awareness. Now, in the electric age, the very instantaneous nature of co-existence among our technological instruments has created a crisis quite new in human history. Our extended faculties and senses now constitute a single field of experience which demands that they become collectively conscious. Our technologies, like our private senses, now demand an interplay and ratio that makes rational co-existence possible. As long as our technologies were as slow as the wheel or the alphabet or money, the fact that they were separate, closed systems was socially and psychically supportable. This is not true now when sight and sound and movement are simultaneous and global in extent. (McLuhan 1962, p.5, emphasis in original)Over forty years later, the seamless interplay that McLuhan demanded between our technologies is still barely visible. McLuhan’s predictions of the spread, and increased importance, of electronic media have of course been borne out, and the worlds of business, science and knowledge storage and transfer have been revolutionised. Yet the integration of electronic systems as open systems remains in its infancy.Advanced Knowledge Technologies (AKT) aims to address this problem, to create a view of knowledge and its management across its lifecycle, to research and create the services and technologies that such unification will require. Half way through its sixyear span, the results are beginning to come through, and this paper will explore some of the services, technologies and methodologies that have been developed. We hope to give a sense in this paper of the potential for the next three years, to discuss the insights and lessons learnt in the first phase of the project, to articulate the challenges and issues that remain.The WWW provided the original context that made the AKT approach to knowledge management (KM) possible. AKT was initially proposed in 1999, it brought together an interdisciplinary consortium with the technological breadth and complementarity to create the conditions for a unified approach to knowledge across its lifecycle. The combination of this expertise, and the time and space afforded the consortium by the IRC structure, suggested the opportunity for a concerted effort to develop an approach to advanced knowledge technologies, based on the WWW as a basic infrastructure.The technological context of AKT altered for the better in the short period between the development of the proposal and the beginning of the project itself with the development of the semantic web (SW), which foresaw much more intelligent manipulation and querying of knowledge. The opportunities that the SW provided for e.g., more intelligent retrieval, put AKT in the centre of information technology innovation and knowledge management services; the AKT skill set would clearly be central for the exploitation of those opportunities.The SW, as an extension of the WWW, provides an interesting set of constraints to the knowledge management services AKT tries to provide. As a medium for the semantically-informed coordination of information, it has suggested a number of ways in which the objectives of AKT can be achieved, most obviously through the provision of knowledge management services delivered over the web as opposed to the creation and provision of technologies to manage knowledge.AKT is working on the assumption that many web services will be developed and provided for users. The KM problem in the near future will be one of deciding which services are needed and of coordinating them. Many of these services will be largely or entirely legacies of the WWW, and so the capabilities of the services will vary. As well as providing useful KM services in their own right, AKT will be aiming to exploit this opportunity, by reasoning over services, brokering between them, and providing essential meta-services for SW knowledge service management.Ontologies will be a crucial tool for the SW. The AKT consortium brings a lot of expertise on ontologies together, and ontologies were always going to be a key part of the strategy. All kinds of knowledge sharing and transfer activities will be mediated by ontologies, and ontology management will be an important enabling task. Different applications will need to cope with inconsistent ontologies, or with the problems that will follow the automatic creation of ontologies (e.g. merging of pre-existing ontologies to create a third). Ontology mapping, and the elimination of conflicts of reference, will be important tasks. All of these issues are discussed along with our proposed technologies.Similarly, specifications of tasks will be used for the deployment of knowledge services over the SW, but in general it cannot be expected that in the medium term there will be standards for task (or service) specifications. The brokering metaservices that are envisaged will have to deal with this heterogeneity.The emerging picture of the SW is one of great opportunity but it will not be a wellordered, certain or consistent environment. It will comprise many repositories of legacy data, outdated and inconsistent stores, and requirements for common understandings across divergent formalisms. There is clearly a role for standards to play to bring much of this context together; AKT is playing a significant role in these efforts. But standards take time to emerge, they take political power to enforce, and they have been known to stifle innovation (in the short term). AKT is keen to understand the balance between principled inference and statistical processing of web content. Logical inference on the Web is tough. Complex queries using traditional AI inference methods bring most distributed computer systems to their knees. Do we set up semantically well-behaved areas of the Web? Is any part of the Web in which semantic hygiene prevails interesting enough to reason in? These and many other questions need to be addressed if we are to provide effective knowledge technologies for our content on the web

    Contracting with General Dental Services: a mixed-methods study on factors influencing responses to contracts in English general dental practice

    Get PDF
    Background: Independent contractor status of NHS general dental practitioners (GDPs) and general medical practitioners (GMPs) has meant that both groups have commercial as well as professional identities. Their relationship with the state is governed by a NHS contract, the terms of which have been the focus of much negotiation and struggle in recent years. Previous study of dental contracting has taken a classical economics perspective, viewing practitioners’ behaviour as a fully rational search for contract loopholes. We apply institutional theory to this context for the first time, where individuals’ behaviour is understood as being influenced by wider institutional forces such as growing consumer demands, commercial pressures and challenges to medical professionalism. Practitioners hold values and beliefs, and carry out routines and practices which are consistent with the field’s institutional logics. By identifying institutional logics in the dental practice organisational field, we expose where tensions exist, helping to explain why contracting appears as a continual cycle of reform and resistance. Aims: To identify the factors which facilitate and hinder the use of contractual processes to manage and strategically develop General Dental Services, using a comparison with medical practice to highlight factors which are particular to NHS dental practice. Methods: Following a systematic review of health-care contracting theory and interviews with stakeholders, we undertook case studies of 16 dental and six medical practices. Case study data collection involved interviews, observation and documentary evidence; 120 interviews were undertaken in all. We tested and refined our findings using a questionnaire to GDPs and further interviews with commissioners. Results: We found that, for all three sets of actors (GDPs, GMPs, commissioners), multiple logics exist. These were interacting and sometimes in competition. We found an emergent logic of population health managerialism in dental practice, which is less compatible than the other dental practice logics of ownership responsibility, professional clinical values and entrepreneurialism. This was in contrast to medical practice, where we found a more ready acceptance of external accountability and notions of the delivery of ‘cost-effective’ care. Our quantitative work enabled us to refine and test our conceptualisations of dental practice logics. We identified that population health managerialism comprised both a logic of managerialism and a public goods logic, and that practitioners might be resistant to one and not the other. We also linked individual practitioners’ behaviour to wider institutional forces by showing that logics were predictive of responses to NHS dental contracts at the dental chair-side (the micro level), as well as predictive of approaches to wider contractual relationships with commissioners (the macro level) . Conclusions: Responses to contracts can be shaped by environmental forces and not just determined at the level of the individual. In NHS medical practice, goals are more closely aligned with commissioning goals than in general dental practice. The optimal contractual agreement between GDPs and commissioners, therefore, will be one which aims at the ‘satisfactory’ rather than the ‘ideal’; and a ‘successful’ NHS dental contract is likely to be one where neither party promotes its self-interest above the other. Future work on opportunism in health care should widen its focus beyond the self-interest of providers and look at the contribution of contextual factors such as the relationship between the government and professional bodies, the role of the media, and providers’ social and professional networks. Funding: The National Institute for Health Research Health Services and Delivery Research programme

    Social Entrepreneurs by Chance: How environmentalists provide a favorable context for social entrepreneurial action.

    Get PDF
    How, why, and under what conditions can social movements contribute to the development of social entrepreneurial process developed by embedded actors? Social entrepreneurship scholars are increasingly adopting social movement theories to explain how individual entrepreneurs develop their social ventures. Despite the synergies achieved when combining social movement with social entrepreneurship literature, social entrepreneurial outcomes are still mostly explained by the efforts of atomistic actors. In this paper we offer an embedded perspective on social entrepreneurship and social movement, which enables us to examine their complementary features in a sustainable development project in a Dutch region. While contentious activity did not produce the desired effect in our case, we found that the various stages of social entrepreneurship processes (opportunity identification, evaluation, formalization, and exploitation) through which embedded actors develop their ventures were especially enhanced by joint knowledge creation between movements and embedded actors, the construction of producer identities, and direct business support. This study contributes to the social movement literature by showing how movements can bring about change by providing embedded actors with producers’ identities and hands-on support. The literature on social entrepreneurship is also complemented, as we show how motives and behaviors to engage in social entrepreneurship are shaped by social movements, in combination with changes in the degree of embeddedness

    Integration of Action and Language Knowledge: A Roadmap for Developmental Robotics

    Get PDF
    “This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder." “Copyright IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.”This position paper proposes that the study of embodied cognitive agents, such as humanoid robots, can advance our understanding of the cognitive development of complex sensorimotor, linguistic, and social learning skills. This in turn will benefit the design of cognitive robots capable of learning to handle and manipulate objects and tools autonomously, to cooperate and communicate with other robots and humans, and to adapt their abilities to changing internal, environmental, and social conditions. Four key areas of research challenges are discussed, specifically for the issues related to the understanding of: 1) how agents learn and represent compositional actions; 2) how agents learn and represent compositional lexica; 3) the dynamics of social interaction and learning; and 4) how compositional action and language representations are integrated to bootstrap the cognitive system. The review of specific issues and progress in these areas is then translated into a practical roadmap based on a series of milestones. These milestones provide a possible set of cognitive robotics goals and test scenarios, thus acting as a research roadmap for future work on cognitive developmental robotics.Peer reviewe

    Texts: A case study of joint action

    Get PDF
    Under embargo until: 2022-04-16Our linguistic communication often takes the form of creating texts. In this paper, we propose that creating texts or ‘texting’ is a form of joint action. We examine the nature and evolution of this joint action. We argue that creating texts ushers in a special type of joint action, which, while lacking some central features of normal, everyday joint actions such as spatio-temporal collocation of agency and embodiment, nonetheless results in an authentic, strong, and unique type of joint action agency. This special type of agency is already present in creating texts in general and is further augmented in creating texts through digital media. We propose that such a unique type of joint action agency has a transformative effect on the experience of our sense of agency and subjectivity. We conclude with the implications of the proposal for social cognition and social agency. The paper combines research in philosophy of mind with the emerging fields of digital humanities and text technology.publishedVersio
    • 

    corecore