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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Régulation de trafic urbain multimodal : une modélisation multi-agents / Cooperative system for multimodal traffic regulation : a multiagent model

Gaciarz, Matthis 05 December 2016 (has links)
Depuis plusieurs décennies, la congestion urbaine est de plus en plus répandue et dégrade la qualité de vie des habitants des villes. Plusieurs méthodes sont utilisées pour diminuer la congestion urbaine, notamment la régulation du trafic et la valorisation des transports en commun. Depuis les années 1990 l'utilisation d‘outils issus de l'intelligence artificielle, et en particulier des méthodes distribuées et les systèmes multi-agents, a permis de concevoir de nouvelles méthodes de régulation du trafic. Parallèlement, l'amélioration des capacités de communication des véhicules et des conducteurs et l'arrivée de voitures autonomes permettent d'envisager de nouvelles approches en matière de régulation. Le travail de recherche proposé dans le cadre de cette thèse est structuré en deux volets. Nous proposons d'abord une méthode de régulation du trafic à une intersection s'appuyant sur la négociation automatique. Notre méthode se fonde sur un système d'argumentation décrivant l'état du trafic et les préférences de chacun, appuyé par des méthodes de raisonnement pour les véhicules et les infrastructures. Dans le deuxième volet de cette thèse, nous proposons une méthode de coordination des bus avec le reste du trafic. Celle-ci permet à un bus de se coordonner de manière anticipative avec les prochaines intersections qu'il prévoit de traverser, afin de mettre en place une politique commune de régulation qui permet au bus d'atteindre son prochain arrêt en subissant le minimum de congestions potentielles / Since several decades, urban congestion is more and more widespread and deteriorate the quality of life of citizens who live in cities. Several methods are used to reduce urban congestion, notably traffic regulation and promotion of public transportation. Since the 1990's, the usage of tools from artificial intelligence, particularly distributed systems and multi-agent systems, allowed to design new methods for traffic regulation. Indeed, these methods ease to take into account the complexity of traffic-related problems with distribution. Moreover, the improvement of the communication abilities of the vehicles and the coming of autonomous vehicles allow to consider new approaches for regulation.The research work presented in this work is twofold. First we propose a method for traffic regulation at an intersection based on automatic negotiation. Our method is based on an argumentation system describing the state of the traffic and the preferences of each vehicle, relying on reasonning methods for vehicles and infrastructures. In the second part of this thesis, we propose a coordination method for buses for the rest of the traffic. This method allows a bus to coordinate in an anticipatory way with the next intersections on its trajectory, in order to define a common regulation policy allowing the bus to reach its next stop without suffering from potential congestions
242

[en] AUTOMATED TEST FOR OPEN MULTI-AGENT SYSTEMS IMPLEMENTED WITH MLAW MIDDLEWARE / [pt] TESTE AUTOMATIZADO PARA SISTEMAS MULTIAGENTES ABERTOS IMPLEMENTADOS COM O MIDDLEWARE M-LAW

LUIZ FERNANDO CHAGAS RODRIGUES 30 January 2007 (has links)
[pt] A complexidade e a distribuição de sistemas multiagentes tornam seu desenvolvimento muito sujeito a falhas. Ao mesmo tempo, poucas iniciativas procuram resolver o problema através de teste automatizado da mesma maneira que no desenvolvimento orientado a objetos. Este trabalho apresenta um framework para o desenvolvimento de aplicações de teste automatizado através de agentes Stubs para o middleware M-Law. O middleware implementa um interpretador para a linguagem XMLaw, atuando como mediador da comunicação dos agentes segundo a definição das leis de interação. / [en] Complexity and distribution of multi-agent systems make the development of such systems failure prone. In this context, few solutions try to solve the problem through automated tests as we see in object oriented development. This work presents a framework for test automated applications development through the use of Stub agents for the middleware M-Law. This middleware implements the law-enforcement mechanism for regulating OMAS specified by the description language XMLaw which implements a law definition language, called XMLaw, for agent interaction in open multi-agent systems.
243

[en] A SOFTWARE AGENTS BASED ARCHITECTURE FOR THE AUTOMATION OF FAULT MANAGEMENT PROCESSES IN TELECOMMUNICATIONS NETWORKS / [pt] UMA ARQUITETURA BASEADA EM AGENTES DE SOFTWARE PARA A AUTOMAÇÃO DE PROCESSOS DE GERÊNCIA DE FALHAS EM REDES DE TELECOMUNICAÇÕES

ADOLFO GUILHERME SILVA CORREIA 11 October 2007 (has links)
[pt] Os últimos anos têm sido marcados pelo significativo crescimento em todo o mundo da demanda por serviços de telecomunicações. Tal cenário de expansão de redes e da necessidade de coexistência e interoperabilidade de diferentes tecnologias de forma economicamente viável proporciona grandes desafios para a gerência, operação e manutenção de redes de telecomunicações. O presente trabalho apresenta alguns dos principais modelos e paradigmas de gerência de redes tradicionalmente empregados em redes de telecomunicações e que ainda hoje são amplamente utilizados pela indústria. Muitos dos modelos apresentados foram significativamente influenciados por conceitos e técnicas oriundos da área de engenharia de software. Uma grande ênfase é dada particularmente ao uso de técnicas baseadas em agentes de software para gerência de redes. Para tanto, importantes conceitos sobre agentes de software são apresentados, assim como exemplos de trabalhos em que agentes de software são utilizados no domínio de gerência de redes. Por fim, é proposta uma arquitetura baseada em agentes de software para gerência de falhas em redes legadas de telecomunicações, que são comumente gerenciadas por sistemas centralizados. O objetivo principal desta arquitetura é permitir o diagnóstico e a correção de falhas de rede de forma a não sobrecarregar o sistema centralizado de gerência. Para tanto, são utilizados agentes de software que distribuem informações mantidas no sistema centralizado para outros agentes do sistema. Desta forma, é possível que os agentes responsáveis por executar os procedimentos de diagnóstico e correção de falhas desempenhem suas atividades sem a necessidade de uma comunicação direta com o sistema centralizado. / [en] The last few years have been marked by a significant and worldwide growth in the demand for telecommunications services. Such scenery of network expansion and the need for coexistence and interoperability of different technologies in an economically viable way provides great challenges for the management, operation and maintenance of telecommunications networks. This work presents some of the main network management models and paradigms traditionally employed in telecommunications networks and that still count with wide adoption in the industry as of this day. Many of the presented models have been significantly influenced by concepts and techniques originated in the software engineering field. A great emphasis is particularly given to the use of network management techniques based on software agents. To this end, important concepts of software agents are presented, as well as examples of works where software agents are used in the network management domain. Finally, an architecture based on software agents used for fault management in legacy telecommunications networks, which are usually managed by centralized systems, is proposed. The main objective of this architecture is to allow the diagnosis and the correction of network faults in a way not to overload the centralized management system. To this end, the architecture uses software agents that distribute information maintained in the centralized management system to other agents of the system. In such way, it is possible for the agents responsible for executing the fault diagnosis and correction procedures to perform their activities without the necessity for direct communication with the centralized system.
244

Uma ontologia funcional de reputação para agentes. / A functional ontology of reputation for agents.

Casare, Sara Jane 09 December 2005 (has links)
Esta dissertação propõe uma Ontologia Funcional de Reputação para agentes. Tal ontologia representa uma parte do conhecimento científico sobre reputação provido tanto pelas Ciências Humanas quanto pelos trabalhos em Inteligência Artificial. Seu objetivo é oferecer uma perspectiva funcional para a representação e análise da reputação como mecanismo de controle social em sociedades de agentes, de forma a sustentar a implementação de modelos de reputação para agentes. A Ontologia Funcional de Reputação foi construída a partir das categorias de conhecimento da Ontologia Funcional do Direito, proposta por Valente (1995), e utiliza a categorização de conceitos definida para o mundo jurídico para a representação do mundo social. A ontologia foi codificada em OWL DL, uma linguagem formal baseada em lógica descritiva. Uma vez construída a ontologia, os conceitos utilizados por diversos modelos e sistemas de reputação foram utilizados na sua avaliação. A utilização de um motor de inferência permitiu comparar estes conceitos, representados por meio de classes OWL, com as classes da ontologia. Tal comparação permite avaliar, de modo preliminar, a adequação do uso da Ontologia Funcional de Reputação como uma possível interlingua entre diversos agentes heterogêneos, cada qual utilizando um modelo de reputação diferente, que necessitam interoperar. / This work presents a Functional Ontology of Reputation for agents. This ontology represents the broad knowledge about reputation produced in some areas of interest such as Social Sciences and Artificial Intelligence. Its goal is to provide a functional perspective both to represent and analyze reputation as a social control mechanism for agent’s societies, in order to support the implementation of reputation model for agents. The Functional Ontology of Reputation employs the primitive categories of knowledge used in the Functional Ontology of Law proposed by Valente (1995). The idea is that the concepts of the legal world can be used to model the social world, through the extension of the concept of legal rule to social norm and the internalization of social control mechanisms in the agent's mind, so far externalized in legal institutions. The Functional Ontology of Reputation contains five main categories that have been borrowed from or inspired by the Functional Ontology of Law: Reputative Knowledge, Responsibility Knowledge, Normative Knowledge, World Knowledge and Common Sense Knowledge.As in the Functional Ontology of Law, the distinction among the categories of the reputation ontology are accomplished according to a functional perspective, in which each component of the reputation system, embedded in the social system, exists to perform a specific function in the effort to achieve social objectives, such as trust, reciprocity and social cooperation. The Functional Ontology of Reputation was implemented in OWL, a description logic language. This ontology was evaluated by using several concepts related to reputation, included in different reputation models and reputation systems. These concepts were defined as OWL classes and a reasoner was used in order to produce the comparison between these concepts and the ontology classes. This comparison allows evaluating, in a preliminary way, the Functional Ontology of Reputation utilization as a possible interlingua between several heterogeneous agents that need to interoperate, despite the utilization of different reputation model.
245

Une architecture de contrôle de systèmes complexes basée sur la simulation multi-agent / A control architecture for complex systems based on multi-agent simulation

Navarrete Gutiérrez, Tomás 24 October 2012 (has links)
Les systèmes complexes sont présents partout dans notre environnement : internet, réseaux de distribution d'électricité, réseaux de transport. Ces systèmes ont pour caractéristiques d'avoir un grand nombre d'entités autonomes, des structures dynamiques, des échelles de temps et d'espace différentes, ainsi que l'émergence de phénomènes. Ce travail de thèse se focalise sur la problématique du contrôle de tels systèmes. Il s'agit de déterminer, à partir d'une perception partielle de l'état du système, quelle(s) actions(s) effectuer pour éviter ou au contraire favoriser certains états globaux du système. Cette problématique pose plusieurs questions difficiles : pouvoir évaluer l'impact au niveau collectif d'actions appliqués au niveau individuel, modéliser la dynamique d'un système hétérogène (plusieurs comportements différents en interaction), évaluer la qualité des estimations issues de la modélisation de la dynamique du système. Nous proposons une architecture de contrôle selon une approche " equation-free ". Nous utilisons un modèle multi-agents pour évaluer l'impact global d'actions de contrôle locales avant d'appliquer la plus pertinente. Associée à cette architecture, une plateforme a été développée pour confronter ces idées à l'expérimentation dans le cadre d'un phénomène simulé de " free-riding " dans les réseaux d'échanges de fichiers pair à pair. Nous avons montré que cette approche permettait d'amener le système dans un état où une majorité de pairs partagent alors que les conditions initiales (sans intervention) feraient évoluer le système vers un état où aucun pair ne partage. Nous avons également expérimenté avec différentes configurations de l'architecture pour identifier les différents moyens d'améliorer ses performances / Complex systems are present everywhere in our environment: internet, electricity distribution networks, transport networks. This systems have as characteristics: a large number of autonomous entities, dynamic structures, different time and space scales and emergent phenomena. This thesis work is centered on the problem of control of such systems. The problem is defined as the need to determine, based on a partial perception of the system state, which actions to execute in order to avoid or favor certain global states of the system. This problem comprises several difficult questions: how to evaluate the impact at the global level of actions applied at a global level, how to model the dynamics of an heterogeneous system (different behaviors issue of different levels of interactions), how to evaluate the quality of the estimations issue of the modeling of the system dynamics. We propose a control architecture based on an ``equation-free'' approach. We use a multi-agent model to evaluate the global impact of local control actions before applying the most pertinent set of actions. Associated to our architecture, an experimental platform has been developed to confront the basic ideas or the architecture within the context of simulated ``free-riding'' phenomenon in peer to peer file exchange networks. We have demonstrated that our approach allows to drive the system to a state where most peers share files, despite given initial conditions that are supposed to drive the system to a state where no peer shares. We have also executed experiments with different configurations of the architecture to identify the different means to improve the performance of the architecture
246

[en] A MULTI-AGENT SYSTEMS FRAMEWORK FOR RFID APPLICATIONS / [pt] UM FRAMEWORK DE SISTEMAS MULTI-AGENTES PARA APLICAÇÕES RFID

FELIPE FORTES NASCIMENTO 07 February 2006 (has links)
[pt] Esta dissertação propõe um framework de sistemas multi- agentes para aplicações do domínio de Radio Frequency Identification (RFID). Esta tecnologia de identificação automática de objetos vem se desenvolvendo rapidamente e promete substituir brevemente a tecnologia atual de identificação de produtos: código de barras. Além de promover o desenvolvimento de hardware para etiquetas e leitoras RFID, novos padrões de identificação estão sendo propostos, desafiando os desenvolvedores de software a produzirem novas soluções para lidar com o novo e maior volume de dados e com a natureza distribuída das leitoras e leituras de objetos. Esta dissertação propõe um framework projetado utilizando-se a abordagem de sistemas multi-agentes (SMA) capaz de instanciar SMA distribuídos que: - Interagem com a infra-estrutura RFID existente (leitoras, etiquetas e middlewares); - Facilitam a geração de informações com semântica de negócios a partir de dados crus gerados por esta infra-estrutura, e; - Facilitam a implementação de novas funcionalidades decorrentes do leque de aplicações vislumbradas pelo surgimento de RFID. / [en] Radio Frequency Identification (RFID) technology along with the Electronic Product Code (EPC) created a new complex environment for warehouses systems and supply chain systems in general. The EPC specification created one more level of identification: the product instance. This new level of identification had blown the volume of data being managed by applications. That fact, along with the deployment of distributed RFID readers, causes the necessity of new applications capable of interacting with this infrastructure and capable of processing, filtering and interpreting these new data. This work proposes a framework for distributed multi-agent systems capable of interacting with a deployed RFID infrastructure.
247

Uma plataforma para agentes em hardware utilizando reconfiguração parcial

Nunes, Érico de Morais January 2018 (has links)
Este trabalho apresenta o projeto e arquitetura de uma plataforma para execução de Agentes com funções implementadas em hardware, tomando vantagem do uso de hardware reconfigurável. Os Agentes em hardware são implementados utilizando dispositivos FPGA (Field-programmable Gate Array). O trabalho estende trabalhos anteriores semelhantes na área, com o diferencial de adicionar suporte às funcionalidades de reconfiguração parcial do hardware, suportar aplicações que demandam alto desempenho em hardware – como processamento de sinais e imagens – e redução de recursos de hardware necessários para execução da interface em software. A plataforma proposta utiliza o framework JADE (Java Agent Development Framework), que é um dos frameworks mais populares no estado da arte de desenvolvimento de Agentes e compatível com outros frameworks de Agentes através da conformidade aos padrões FIPA (Foundation for Intelligent Physical Agents). Com o uso do JADE, a plataforma possibilita a comunicação entre Agentes com funções implementadas em hardware e Agentes puramente implementados em software dentro de um mesmo SMA (Sistema Multi-Agente). Uma funcionalidade notável do JADE é a possibilidade de migração de Agentes entre plataformas de um mesmo SMA. Através do uso da reconfiguração parcial de hardware em conjunto com o JADE, a plataforma permite a migração de Agentes de software para hardware e vice-versa, além de suportar reconfiguração de múltiplos Agentes em hardware com um único FPGA. A plataforma faz uso de um único chip através do uso de um processador soft core implementado na lógica programável. O uso deste processador é um diferencial neste trabalho, e mostra que é possível utilizar o JADE em sistemas embarcados com recursos de processamento limitados. Ou seja, em um Agente cuja principal função é implementada em hardware, basta um processador bastante simples para atuar como uma interface entre o hardware e o framework de Agentes. O uso do processador dentro do FPGA tem também o benefício de oferecer formas de acesso mais integrado ao hardware, permitindo maior desempenho na transmissão de dados ao hardware. A plataforma foi validada através de estudos de caso de Agentes com implementações em hardware e em software, incluindo um estudo de caso aplicado de processamento de imagem embarcado utilizando VANTs (Veículos Aéreos Não-Tripulados). O estudo também apresenta comparações de desempenho entre a execução dos Agentes em hardware e em outras plataformas embarcadas de prateleira. Os experimentos realizados mostram um ganho significativo de desempenho nas implementações em FPGA, especialmente considerando processamento de imagens de alta resolução, mesmo considerando que o FPGA executa em frequências consideravelmente reduzidas em comparação às outras plataformas testadas. / This work described the design and architecture of a platform for execution of Agents whose functions are implemented in hardware, by leveraging the use of reconfigurable hardware. The hardware Agents are implemented using FPGA (Field-programmable Gate Array) devices. This work extends previous similar work in this field, while adding the features of hardware partial reconfiguration, supporting applications which require high performance in hardware – such as image or signal processing – and reducing the hardware resource for the software interface execution. The proposed platform makes use of the JADE (Java Agent Development Framework) framework, which is one of the most popular frameworks in state-of-the-art Agent development, and is also compatible with other Agent development frameworks due to compliance with FIPA (Foundation for Intelligent Physical Agents) standards. With the use of JADE, the platform enables communication among Agents which are implemented in hardware and Agents purely implemented in software, inside the same MAS (Multi-Agent System). One notable feature of JADE is the possibility of migrating Agents among platforms inside a single MAS. Through the use of hardware partial reconfiguration along with JADE, the platform enables the migration of Agents from software to hardware and viceversa, in addition to supporting múltiple hardware Agents in a single FPGA. The platform makes use of a single chip, by using a MicroBlaze soft core processor implemented in programmable logic. The use of this processor is a distinction on this work, and it shows that it is possible to use JADE on embedded systems with limited processing power. That is, in an Agent whose main function is implemented in hardware, a very simple processor to act as an interface between hardware and the Agent framework is enough. The use of the soft core processor inside the FPGA also has the benefit of offering more integrated ways of accessing hardware, enabling higher performance for transferring data to hardware. The platform was validated through case studies of hardware and software Agent implementation, including a case study applied to image processing using UAVs (Unmanned Aerial Vehicles). The study also shows performance comparisons between the Agent execution in hardware and in other off-the-shelf embedded platforms. The performed experiments report a significative performance increase in the FPGA implementations, particularly in high resolution image processing, even considering that the FPGA runs in considerably lower clock frequency than the other tested platforms.
248

Taming NFV orchestration using decentralised cognitive components / Orquestrador NFV descentralizado baseado em raciocínio BDI

Schardong, Frederico January 2018 (has links)
Network Functions Virtualisation (NFV) separa as funções de rede dos dispositivos físicos, simplificando a implantação de novos serviços. As típicas funções de rede, como firewalls, aceleradores de tráfego, sistemas de detecção de intrusão e sistemas de prevenção de intrusões, são tradicionalmente realizadas por equipamentos físicos proprietários, que devem ser instalados manualmente pelos operadores de rede. A implantação de equipamentos físicos é desafiadora porque eles têm requisitos específicos de encadeamento e ordenação. Ao contrário dos equipamentos físicos tradicionais, as funções de rede virtuais (VNFs) podem ser dinamicamente implementadas e reconfiguradas sob demanda, colocando desafios de gerenciamento rigorosos aos sistemas em rede. A seleção das VNFs mais apropriadas para atingir um objetivo específico e a decisão sobre onde implantar essas VNFs e por quais caminhos elas se comunicarão são responsabilidades de um orquestrador de NFV. Nesta dissertação, propomos orquestrar VNFs usando componentes cognitivos interativos estruturados com a arquitetura belief-desire-intention (BDI), levando a soluções emergentes para enfrentar os desafios da rede. A arquitetura BDI inclui um ciclo de raciocínio que fornece aos agentes um comportamento racional, permitindo que lidem com diferentes cenários nos quais o comportamento flexível e inteligente é necessário. Estendemos a arquitetura NFV substituindo seu orquestrador centralizado por agentes BDI. Nossa proposta inclui um protocolo de leilão reverso e uma nova heurística de licitação que permite que os agentes tomem decisões sobre as tarefas de orquestração. Por fim, nós fornecemos uma plataforma de testes que integra uma plataforma para o desenvolvimento de agentes BDI com um emulador de rede, permitindo que os agentes controlem as VNFs e percebam a rede. Essa plataforma de testes é usada para implementar VNFs e avaliar empiricamente nosso modelo teórico em um ataque de negação de serviço distribuído. Os resultados da avaliação mostram que uma solução para o ataque DDoS surge através da negociação de agentes, mitigando com sucesso o ataque. / Network Functions Virtualisation (NFV) decouples network functions from physical devices, simplifying the deployment of new services. Typical network functions, like firewalls, traffic accelerators, intrusion detection systems and intrusion prevention systems, are traditionally performed by proprietary physical appliances, which must be manually installed by network operators. Their deployment is challenging because they have specific chaining requirements. As opposed to traditional physical appliances, virtual network functions (VNFs) can be dynamically deployed and reconfigured on demand, posing strict management challenges to networked systems. The selection of the most appropriate VNFs to achieve a particular objective, the decision on where to deploy these VNFs and through which paths they will communicate are the responsibilities of an NFV orchestrator. In this dissertation, we propose to orchestrate VNFs using interacting cognitive components structured with the belief-desire-intention (BDI) architecture, leading to emergent solutions to address network challenges. The BDI architecture includes a reasoning cycle, which provides agents with rational behaviour, allowing agents to deal with different scenarios in which flexible and intelligent behaviour is needed. We extend the NFV architecture, replacing its centralised orchestrator with BDI agents. Our proposal includes a reverse auction protocol and a novel bidding heuristic that allow agents to make decisions regarding the orchestration tasks. Finally, we provide a testbed that integrates a platform for developing BDI agents with a network emulator, allowing agents to control VNFs and perceive the network. This testbed is used to implement VNFs and empirically evaluate our theoretical model in a distributed denial-of-service (DDoS) attack. The evaluation results show that a solution to the DDoS attack emerges through the negotiation of agents, successfully mitigating the attack.
249

Avaliação do impacto da confiança em cadeias de suprimentos através de simulação baseada em agentes. / Impact of trust on agent-based simulation for supply chains.

André Domingues da Silva Jalbut 24 October 2018 (has links)
Empresas em cadeias de suprimentos têm como objetivo maximizar suas produtividades, e consequentemente seus lucros. Uma maneira de estudar o comportamento destas cadeias é simulá-las utilizando uma abordagem multi-agentes. Neste trabalho, adicionamos múltiplos agentes nos níveis de um modelo amplamente adotado na literatura, denominado Beer Game, para avaliar a eficiência local e global dos fornecedores. Para tal, utilizamos perfis distintos baseados em confiança ou em preço. Medimos o impacto de usar tais políticas de seleção no capital acumulado pelos agentes, e concluímos que as parcerias baseadas em confiança são recomendáveis em cenários com ampla disseminação de informações verdadeiras, enquanto que as baseadas em lucro são mais vantajosas em cenários marcados por pouca comunicação ou pelo espalhamento de informações falsas. / Companies in supply chains have the objective of maximizing their productivities, and consequently their profits. A way of to study the behavior of these chains is to simulate them using a multi-agent-based approach. In this work, we added multiple agents at the levels of a widely adopted model in the literature, called Beer Game, to evaluate the local and global performance of suppliers. To do this, we use distinct profiles based on trust or price. We measure the impact of using such selection policies on the agents\' profit, and we could conclude that trust-based partnerships are recommended in scenarios with wide dissemination of true information, while profit-based partnerships are most advantageous in scenarios marked by poor communication or spreading false information.
250

Automated service negotiation between autonomous computational agents

Faratin, Peyman January 2000 (has links)
Multi-agent systems are a new computational approach for solving real world, dynamic and open system problems. Problems are conceptualized as a collection of decentralised autonomous agents that collaborate to reach the overall solution. Because of the agents autonomy, their limited rationality, and the distributed nature of most real world problems, the key issue in multi-agent system research is how to model interactions between agents. Negotiation models have emerged as suitable candidates to solve this interaction problem due to their decentralised nature, emphasis on mutual selection of an action, and the prevalence of negotiation in real social systems. The central problem addressed in this thesis is the design and engineering of a negotiation model for autonomous agents for sharing tasks and/or resources. To solve this problem a negotiation protocol and a set of deliberation mechanisms are presented which together coordinate the actions of a multiple agent system. In more detail, the negotiation protocol constrains the action selection problem solving of the agents through the use of normative rules of interaction. These rules temporally order, according to the agents' roles, communication utterances by specifying both who can say what, as well as when. Specifically, the presented protocol is a repeated, sequential model where offers are iteratively exchanged. Under this protocol, agents are assumed to be fully committed to their utterances and utterances are private between the two agents. The protocol is distributed, symmetric, supports bi and/or multi-agent negotiation as well as distributive and integrative negotiation. In addition to coordinating the agent interactions through normative rules, a set of mechanisms are presented that coordinate the deliberation process of the agents during the ongoing negotiation. Whereas the protocol normatively describes the orderings of actions, the mechanisms describe the possible set of agent strategies in using the protocol. These strategies are captured by a negotiation architecture that is composed of responsive and deliberative decision mechanisms. Decision making with the former mechanism is based on a linear combination of simple functions called tactics, which manipulate the utility of deals. The latter mechanisms are subdivided into trade-off and issue manipulation mechanisms. The trade-off mechanism generates offers that manipulate the value, rather than the overall utility, of the offer. The issue manipulation mechanism aims to increase the likelihood of an agreement by adding and removing issues into the negotiation set. When taken together, these mechanisms represent a continuum of possible decision making capabilities: ranging from behaviours that exhibit greater awareness of environmental resources and less to solution quality, to behaviours that attempt to acquire a given solution quality independently of the resource consumption. The protocol and mechanisms are empirically evaluated and have been applied to real world task distribution problems in the domains of business process management and telecommunication management. The main contribution and novelty of this research are: i) a domain independent computational model of negotiation that agents can use to support a wide variety of decision making strategies, ii) an empirical evaluation of the negotiation model for a given agent architecture in a number of different negotiation environments, and iii) the application of the developed model to a number of target domains. An increased strategy set is needed because the developed protocol is less restrictive and less constrained than the traditional ones, thus supporting development of strategic interaction models that belong more to open systems. Furthermore, because of the combination of the large number of environmental possibilities and the size of the set of possible strategies, the model has been empirically investigated to evaluate the success of strategies in different environments. These experiments have facilitated the development of general guidelines that can be used by designers interested in developing strategic negotiating agents. The developed model is grounded from the requirement considerations from both the business process management and telecommunication application domains. It has also been successfully applied to five other real world scenarios.

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