2,031 research outputs found
Methodologies for self-organising systems:a SPEM approach
We define ’SPEM fragments’ of five methods for developing self-organising multi-agent systems. Self-organising traffic lights controllers provide an application scenario
A Self-healing Architecture based on RAINBOW for Industrial Usage
Over recent decades computer and software systems become more and more complex because of the applications’
and user’s requirements. The complexity makes the software systems more vulnerable to the error and bugs. Also, environmental situations affect software systems which do not react to the environmental activities. Self-healing architectures have been proposed in order to make systems defeat these problems and to make systems capable of reacting to the environmental activity. Hence, these architectures help system to become dynamic and more robust, but finding a proper architecture which can support and cover system’s requirements is an issue. This is particularly true in industrial environments, which consist of some known and some unknown parameters.
This paper presents an architecture that can be used in some industrial environment to facilitate the process of adapting the system to unpredicted situations. This architecture has been developed over the base of RAINBOW infrastructure and it is compliant to the MAPE control loop (Autonomic Computing control loop). The paper reports also about the practical experience of implementing this architecture for a painter robot in an automotive factory, which deals with problems in painted part by itself. The proposed architecture uses rule-based reasoning and it actualizes the method of environmental modeling by using a rule-based system as the model extractor. The results of the implementation shows huge benefits in reusability and even in the quality of painting process
Patterns for self-adaptive systems: agent-based simulations
Self-adaptive systems are distributed computing systems that can adapt their behavior and structure to
different kinds of conditions. This adaptation does not concern the single components only, but the entire
system. In a previous work we have identified several patterns for self-adaptation, classifying them by means
of a taxonomy, which aims at being a support for developers of self-adaptive systems. Starting from that
theoretical work, we have simulated the described self-adaptation patterns, in order to better understand the
concrete and real features of each pattern. The contribution of this paper is to report about the simulation
work of three patterns as examples, detailing how it was carried out, in order to provide a further support for
the developers
Cross-cultural adaptation and validation of the Portuguese version of the Knee Outcome Survey-Activities of Daily Living Scale (KOS-ADLS)
Abstract The objective of this study was to cross-culturally adapt and validate the Portuguese version of the Knee Outcome Survey-Activities of Daily Living Scale (KOS-ADLS). This version was obtained with forward/backward translations, consensus panels and pre-testing. The Portuguese KOS-ADLS and Medical Outcomes Study, 36-item Short Form (SF-36) questionnaires, visual analogue scales (VAS) of pain, disability and discomfort, and a form for patient’s characteristics were administered to 168 subjects with knee osteoarthritis (OA). Reliability was acceptable (Cronbach’s alpha?=?0.91; ICC?=?0.97). There were significant correlations with SF-36 physical component subscales, all VAS, and duration of knee OA. The subjects with bilateral knee OA and that need walking aids obtained lower scores (p?<?0.001). No floor/ceiling effects were detected. Responsiveness to physical therapy was showed (standardized effect size?=?0.62; standardized response mean?=?1.02). The Portuguese KOS-ADLS evidenced acceptable reliability, validity, floor/ceiling effects, and responsiveness
Building self-adaptive systems by adaptation patterns integrated into agent methodologies
Adopting patterns, i.e. reusable solutions to generic problems, turns out to be useful to rely on tested solutions and to avoid reinventing the wheel. To this aim, we proposed to use adaptation patterns to build systems that exhibit self-adaptive features. However, these patterns would be more usable if integrated in a methodology exploited to develop a system. In this paper we show how our Catalogue of adaptation patterns can be integrated into methodologies for adaptive systems; more in detail, we consider methodologies which support the development of multi-agent systems that can be considered good examples of adaptive systems. The paper, in particular, shows the integration of our Catalogue of adaptive patterns into the PASSI methodology, together with the graphical tool that we developed to support it
Location-dependent services for mobile users
Abstract—One of the main issues in mobile services ’ research (M-service) is supporting M-service availability, regardless of the user’s context (physical location, device employed, etc.). However, most scenarios also require the enforcement of context-awareness, to dynamically adapt M-services depending on the context in which they are requested. In this paper, we focus on the problem of adapting M-services depending on the users ’ location, whether physical (in space) or logical (within a specific distributed group/application). To this end, we propose a framework to model users ’ location via a multiplicity of local and active service contexts. First, service contexts represent the mean to access to M-services available within a physical locality. This leads to an intrinsic dependency of M-service on the users’ physical location. Second, the execution of service contexts can be tuned depending on who is requesting what M-service. This enables adapting M-services to the logical location of users (e.g., a request can lead to different executions for users belonging to different groups/applications). The paper firstly describes the framework in general terms, showing how it can facilitate the design of distributed applications involving mobile users as well as mobile agents. Then, it shows how the MARS coordination middleware, implementing service contexts in terms of programmable tuple spaces, can be used to develop and deploy applications and M-services coherently with the above framework. A case study is introduced and discussed through the paper to clarify our approach and to show its effectiveness. Index Terms—Context-awareness, coordination infrastructures, M-services, mobility, multiagent systems. I
Smart Meter Aware Domestic Energy Trading Agents
The domestic energy market is changing with the increasing availability of energy micro-generating facilities. On the long run, households will have the possibility to trade energy for purchasing to and for selling from a number of different actors. We model such a futuristic scenario using software agents. In this paper we illustrate an implementation including the interfacing with a physical Smart Meter and provide initial simulation results. Given the high autonomy of the actors in the domestic market and the complex set of behaviors, the agent approach proves to be effective for both modeling and simulating purposes
An adaptive agent-based system for deregulated smart grids
The power grid is undergoing a major change due mainly to the increased penetration of renewables and novel digital instruments in the hands of the end users that help to monitor and shift their loads. Such transformation is only possible with the coupling of an information and communication technology infrastructure to the existing power distribution grid. Given the scale and the interoperability requirements of such future system, service-oriented architectures (SOAs) are seen as one of the reference models and are considered already in many of the proposed standards for the smart grid (e.g., IEC-62325 and OASIS eMIX). Beyond the technical issues of what the service-oriented architectures of the smart grid will look like, there is a pressing question about what the added value for the end user could be. Clearly, the operators need to guarantee availability and security of supply, but why should the end users care? In this paper, we explore a scenario in which the end users can both consume and produce small quantities of energy and can trade these quantities in an open and deregulated market. For the trading, they delegate software agents that can fully interoperate and interact with one another thus taking advantage of the SOA. In particular, the agents have strategies, inspired from game theory, to take advantage of a service-oriented smart grid market and give profit to their delegators, while implicitly helping balancing the power grid. The proposal is implemented with simulated agents and interaction with existing Web services. To show the advantage of the agent with strategies, we compare our approach with the “base” agent one by means of simulations, highlighting the advantages of the proposal
O efeito das ligaduras funcionais da articulação tíbio-társica na propriocepção: revisão da literatura
Introdução: A ligadura funcional na articulação tíbio-társica é utilizada com fins terapêuticos ou preventivos. A sua eficácia pode ser atribuída à limitação mecânica que implica, mas também pode envolver processos neurofisiológicos relacionados com o feedback proprioceptivo. Existem instrumentos de medida que avaliam objectivamente algumas componentes da propriocepção. Objectivos: Realizar uma revisão da literatura sobre o efeito das ligaduras funcionais da articulação tíbio-társica na propriocepção. Relevância: O conhecimento sobre o tema pode constituir mais uma informação que contribui para decisão dos fisioterapeutas ou outros profissionais de saúde quanto à aplicação da ligadura funcional na articulação tíbio-társica. Metodologia: Com base numa metodologia sistemática, foi realizada uma revisão dos artigos publicados entre 1987 e 2007, pesquisados nas bases de dados referenciais PubMed e PEDro. Foram seleccionados os artigos que cumpriam com os critérios de selecção e eliminados os restantes. Resultados e discussão: Dos 66 artigos provenientes das pesquisas, foram seleccionados 10 artigos. Constatou-se que cinco artigos referem que as ligaduras funcionais não apresentam qualquer efeito sobre a propriocepção. Um estudo verificou alterações benéficas que desapareciam após o exercício físico.
Dois estudos referem que a ligadura funcional poderá intervir positivamente nos sistemas proprioceptivos implicados na estabilidade dinâmica. Apenas um estudo refere que a ligadura poderá ter um efeito prejudicial sobre a propriocepção. Conclusão: Os resultados dos estudos não são unânimes quanto aos efeitos da ligadura funcional da articulação tíbio-társica na propriocepção. É necessária a realização
de mais estudos com desenhos experimentais de maior qualidade metodológica
Introduction to the Special Issue on Enabling Technologies for Collaborations
Collaboration is an important aspect in almost all elds of human life, and today the need for supporting
collaboration is increased by the fact that we are always connected by means of different kinds of devices. In
particular in the enterprise world, this need has emerged and satisfying it can lead to relevant bene ts for
companies. In the last years, enabling technologies have evolved to meet new and challenging requirements.
The aim of this special issue is to provide a selection of the state of the art, emerging trends, new technologies
and best practices in the eld of technologies that enable collaboration. The idea was born at the 2014 IEEE
WETICE Conference on Enabling Technology: Infrastructure for Collaborative Enterprises, but the call was
open to any submission
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