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An organizational ontology for multiagent-based Enterprise Process modeling and automationLin, Yishuai 10 September 2013 (has links) (PDF)
The work presented in this PhD thesis defines a new approach for the modeling and the conceptualization of enterprise business processes in the perspective of building intelligent assistance software tools to support these processes. The proposed approach defines an organizational ontology, named K-CRIO. Its description is based on the Ontology Web Language. To illustrate our work, an intelligent assistance system has been designed and implemented according to the result from the modeling and conceptualization of a specific business process with the K-CRIO Ontology. It is a web-based application that integrates and takes full advantage of multi-agent systems.The K-CRIO Ontology is an Ontology dedicated to the study of organizations and the analysis of business processes adopting an organizational point of view. Specifically, it is used to understand, analyze and reason about organizations and the processes they implement. The targeted organizations are those composed of entities involved throughout products' design and, to do so, following a defined business process. The range of this type of organizations is quite wide. We have thus limited our study to organizations that produce software as the final process goal, specifically IT enterprises delivering software products or services. In this context, the K-CRIO ontology could be used to model structure of the considered organizations and model human activities appearing in their business processes. This ontology could be used to support process assistance within the described organizations. More specifically, the ontology could provide means for reasoning, annotating resources, monitoring design processes, enabling searches and pro-actively proposing tips and proper content. In order to illustrate the usage of K-CRIO, we apply K-CRIO on two different processes: the Waterfall Model and the Scrum methodology. These examples are both classical software-development processes. Moreover, for Scrum, the famous agile software-development process widely used in software enterprises, we have designed and developed an intelligent assistance tool. This tool mainly helps Scrum Masters to make decision by monitoring Scrum project teams' activities within their various projects and collecting knowledge about these activities.
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Agents situés dans l'image et organisés en pyramide irrégulière: Contribution à la segmentation par une approche d'agrégation coopérative et adaptativeDuchesnay, Edouard 13 December 2001 (has links) (PDF)
Les agents situés dans l'image fournissent un cadre privilégié pour la mise en oeuvre de stratégies coopératives et localement adaptées en segmentation d'image. Ils facilitent l'intégration des connaissances a priori, expressions d'un modèle, permettant ainsi de dégager de nouvelles contraintes indispensables à toutes les étapes de la vision par ordinateur (de la segmentation à l'interprétation). Nous proposons un cadre conceptuel pour l'architecture logicielle d'un système de vision bas-niveau basée sur des agents situés dans l'image. Une telle architecture est articulée en trois niveaux d'analyse et de description : 1. Description globale et structurelle de l'organisation regroupant les agents. Cette étape de description s'attache à établir les liens entre agents. Nous proposons comme élément organisationnel la pyramide irrégulière qui impose sa structure à la population d'agents, afin de garantir un comportement globalement contrôlable et convergent de ces derniers. 2. Description locale, fonctionnelle et comportementale des agents composant le système. Nous proposons une mise en oeuvre particulière de l'architecture logicielle de vision bas-niveau. Dans cette dernière, deux familles d'agents, qui traduisent des primitives région et contour, interagissent localement au sein de la pyramide. Notre objectif est de montrer comment cette méthodologie permet une implémentation riche, flexible et distribuée des aspects précédemment identifiés; à savoir : l'adaptation locale, l'intégration et l'expression d'incertitudes dans l'information a priori et des traitements coopératifs région/région et région/contour. 3. Finalement, une analyse globale, comparative et fonctionnelle vérifie que l'ensemble des interactions locales produit une bonne segmentation des images. Nous comparons notre approche avec d'autres méthodes de segmentation sur des images médicales et des images de synthèse.
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Design and Development of an Intelligent Energy Controller for Home Energy Saving in Heating/Cooling SystemAbaalkhail, Rana 18 January 2012 (has links)
Energy is consumed every day at home as we perform simple tasks, such as watching television, washing dishes and heating/cooling home spaces during season of extreme weather conditions, using appliances, or turning on lights. Most often, the energy resources used in residential systems are obtained from natural gas, coal and oil. Moreover, climate change has increased awareness of a need for expendable, energy resources. As a result, carbon dioxide emissions are increasing and creating a negative effect on our environment and on our health. In fact, growing energy demands and limited natural resource might have negative impacts on our future. Therefore, saving energy is becoming an important issue in our society and it is receiving more attention from the research community.
This thesis introduces a intelligent energy controller algorithm based on software agent approach that reduce the energy consumption at home for both heating and cooling spaces by considering the user’s occupancy, outdoor temperature and user’s preferences as input to the system. Thus the proposed approach takes into consideration the occupant’s preferred temperature, the occupied and unoccupied spaces, as well as the time spent in each area of the home.
A Java based simulator has been implemented to simulate the algorithm for saving energy in heating and cooling systems. The results from the simulator are compared to the results of using HOT2000, which is Canada’s leading residential energy analysis and rating software developed by CanmetENERGY’s Housing, Buildings, Communities and Simulation (HBCS) group. We have calculated how much energy a home modelled will use under emulated conditions. The results showed that the implementation of the proposed energy controller algorithm can save up to 50% in energy consumption in homes dedicated to heating and cooling systems compared to the results obtained by using HOT2000.
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Flocking for Multi-Agent Dynamical SystemsWan, Zhaoxin January 2012 (has links)
In this thesis, we discuss models for multi-agent dynamical systems. We study the tracking/migration problem for flocks and a theoretical framework for design and analysis of flocking algorithm is presented. The interactions between agents in the systems are denoted by potential functions that act as distance functions, hence, the design of proper potential functions are crucial in modelling and analyzing the flocking problem for multi-agent dynamical systems. Constructions for both non-smooth potential functions and smooth potential functions with finite cut-off are investigated in detail.
The main contributions of this thesis are to extend the literature of continuous flocking models with impulsive control and delay. Lyapunov function techniques and techniques for stability of continuous and impulsive switching system are used, we study the asymptotic stability of the equilibrium of our models with impulsive control and discovery that by applying impulsive control to Olfati-Saber's continuous model, we can remove the damping term and improve the performance by avoiding the deficiency caused by time delay in velocity sensing.
Additionally, we discuss both free-flocking and constrained-flocking algorithm for multi-agent dynamical system, we extend literature results by applying velocity feedbacks which are given by the dynamical obstacles in the environment to our impulsive control and successfully lead to flocking with obstacle avoidance capability in a more energy-efficient way.
Simulations are given to support our results, some conclusions are made and future directions are given.
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Design and implementation of a multi-agent systems laboratoryJones, Malachi Gabriel 19 May 2009 (has links)
This thesis presents the design, development, and testing of a multi-agent systems laboratory that will enable the experimental investigation of Networked Control
Systems. Networked Control Systems (NCS) are integrations of computation, networking, and physical dynamics, in which embedded devices are networked to sense,
monitor, execute collaborative tasks, and interact with the physical world. As the potential for applications of NCS has increased, so has the research interest in this area.
Possible applications include search and rescue, scientific data collection, and health
care monitoring systems. One of the primary challenges in applying NCS is designing
distributed algorithms that will enable the networked devices to achieve global objectives. Another challenge is in ensuring that distributed algorithms have the necessary
robustness to achieve those global objectives in dynamic and unpredictable environments. A multi-agent systems laboratory provides the researcher with a means to
observe the behavior and performance of distributed algorithms as they are executed
on a set of networked devices. Through this observation, the researcher may discover
robustness issues that were not present in computer simulation. The objective of
this research is to design and implement the infrastructure for a multi-agent systems
laboratory to observe distributed algorithms implemented on networked devices.
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An agent-based location evaluation modelSirikijpanichkul, Ackchai January 2008 (has links)
Truck transportation is considered as a favourable mode by shippers to carry freight at most ranges of distance as it has more flexibility in fleet size, capacity, scheduling, routing, and access. Although truck is considered as the popular mode for freight transportation, road-rail intermodal freight transportation becomes an attractive alternative to road only mode since the latter has no longer assured a reliable service due to traffic congestion problem. It also raises public concern in environmental and road safety impacts. Intermodal freight transportation is defined as a system that carries freight from origin to destination using two or more transportation modes where transfers between modes occur at an intermodal freight terminal. Success of the terminal depends on four major factors, namely: location, efficiency, financial sustainability, and rail level of service. Among these, the location is one of the most crucial success factors and needs to be considered carefully as it has direct and indirect impacts on a number of stakeholders including terminal users, terminal operators, transport network infrastructure providers, and community. Limitations of previous terminal location evaluation models in representing individual preference and behaviour as well as accommodating negotiation and communication between the players bring in an opportunity to develop a new model which is more flexible and capable of providing a solution that is not necessary to be optimal, but acceptable for every player without requiring explicit trade-offs. This thesis is aimed at demonstrating the feasibility of applying an agent-based approach to the evaluation of intermodal freight terminal location and investigating terminal effectiveness against stakeholder equity and some important aspects arising from the different stakeholders’ viewpoints. Agent technologies were introduced to model the stakeholders as individual agents. The agent concept was adopted to develop a decentralised location evaluation system that is able to balance the terminal effectiveness with the stakeholder equity. The proposed agent-based location evaluation model was modelled as a hierarchical control system that comprises three decision levels: local level, stakeholder level and policy level. Policy level is the highest decision level, which is represented by a policy maker. Apart from the policy level, the rest can be viewed as operational decision levels. Local level is the lowest control level. At this level, each stakeholder was classified into stakeholder groups based on their characteristics and interest. The terminal scenarios were then evaluated based on benefit maximisation criteria. Stakeholder control is the higher control level than the local level. It represents the control level where negotiations and decisions between groups of people (stakeholders) with different point of views are made. At this level, negotiation process was used to determine terminal location based on preference and equity of stakeholders. The determined terminal site was then used in the evaluation against constraints to ensure that all agents are satisfied. The terminal location decision for South East Queensland (SEQ) was applied as a case study of this thesis. The SEQ strategic freight transport model was developed, calibrated, and validated to assist in providing inputs for the evaluation of terminal location. The results indicated that for the developed agent-based location evaluation model, Yatala was selected as the most appropriate terminal location that results in the highest effectiveness and equity (as measured by level of satisfaction and Gini coefficient, respectively). Other location evaluation models were also used in comparison with the developed agent-based location evaluation model. Those include P-Median, P-Centre, and maximum covering models. It was found that the agent-based location evaluation model outperformed the other location evaluation models. Finally, a sensitivity analysis was conducted in order to evaluate the consistency of model outputs against the uncertainties in the input parameters. In most cases, the terminal location decisions obtained from the developed agent-based location evaluation model was not sensitive to the changes in those parameters. However, the results suggested that when a unit cost of truck travel delay increased, the impact on the final terminal location decisions was observed. This thesis demonstrated the feasibility of applying a decentralised approach to terminal location decision problem using a multi-agent concept and evaluating it against other well-known location problems. A new framework and methodology for the planning of intermodal terminal location evaluation was also formulated. Finally, the problems of terminal location evaluation and optimisation of intermodal freight terminal operation were integrated into a single evaluation model.
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Desenvolvimento de sistemas de automação da manufatura usando arquiteturas orientadas a serviço e sistemas multi-agentesPeixoto, João Alvarez January 2012 (has links)
Os requisitos de manufatura industrial apontam uma necessidade de reconfiguração e reprogramação do fluxo de processo, a fim de atender modificações no produto com as mudanças dos requisitos de mercado. Estas mudanças implicam em alterações no processo de fabricação, o que, em muitos casos, significa alterar o leiaute, reprogramar controladores, modificar acoplamentos e interfaceamentos, etc. Os tamanhos dos lotes de produção estão ficando menores e a variedade de produtos em uma mesma linha tem aumentado. Isto torna o tempo de preparação dos dispositivos de manufatura fator crucial na formação do custo final. Dispositivos com mais autonomia, capazes de se autogerenciar e que permitam uma troca rápida de funcionalidades passam a serem desejados em um ambiente de manufatura, onde os sistemas convencionais com programação centralizada, sequência definida no controlador central e arranjo de funcionalidades fixas deixam a desejar. Orientação a serviços é um conceito que propõe a descentralização do controle e a disposição de componentes de forma a se agruparem virtualmente e formar novos dispositivos, com novas funcionalidades, otimizando investimento, recurso e tempo de produção. Nesta abordagem os equipamentos passam a se comportar como agentes de manufatura, em um universo de multi-agentes, que negociam entre si o processo requerido, propiciando o atendimento à variação de produto e dispondo de um número maior de funcionalidades, o que reduz o tempo de troca de processos. Um estudo de caso de um sistema orientado a serviços, sob uma plataforma multi-agentes, é proposto neste trabalho, buscando fornecer subsídios para a análise de desempenho e potencialidades deste conceito. / The industrial manufacturing requirements indicate a need for reconfiguration and reprogramming of process flow in order to meet changes in the product with the changing market requirements. These changes imply changes in the manufacturing process, which in many cases, means changing the layout, reprogram controllers, modify interfaces and couplings etc. The production lot sizes are getting smaller and the variety of products in the same line has increased. This makes the preparation time of manufacturing devices crucial factor in the formation of the final cost. Devices with more autonomy, able to manage themselves and allow a rapid exchange of features are to be desired in a manufacturing environment, where conventional systems with centralized scheduling, sequence defined in the central controller and array of features still fall short. Service orientation is a concept that proposes to decentralize the control and disposition of components in order to regroup virtually and form new devices with new features, optimizing investment, resource and production time. In this approach the devices start to act as agents of manufacturing, in a universe of multi-agents, who negotiate among themselves the process required, providing care for the product variation and having a greater number of features, which reduces the switching time processes. A case study of system-oriented services, under a multi-agent platform is proposed in this work, aiming to provide tools for performance analysis and potential of the concept.
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Simulação de uso de solo urbano utilizando uma abordagem baseada em sistemas multiagentes reativos / Land use simulation based in Multi-Agents Reactive SystemsBastos, André Dias January 2007 (has links)
O planejamento urbano é muito importante para garantir o desenvolvimento sustentável das cidades modernas. Para isso, muitos aspectos devem ser considerados, tais como o crescimento urbano das mesmas, uma vez que, o entendimento das dinâmicas desse fenômeno é um pré-requisito para modelar e prever tendências futuras de mudanças de uso do solo/cobertura da terra (LUCC) e seus impactos ecológicos. Como as cidades são sistemas complexos, que envolvem vários atores com diferentes padrões de comportamento, uma das mais promissoras classes de modelos urbanos designados para simular e analisar mudanças de uso do solo são as baseadas em Sistemas Multiagentes (SMA). Sendo assim, este trabalho descreve uma proposta de abordagem baseada em agentes reativos aplicados na tarefa de simulação de crescimento urbano para a cidade de Bauru/SP, utilizando dados geográficos, extraídos de imagens de satélite, da ocupação e utilização efetiva do uso do solo dessa cidade em um período de aproximadamente trinta e cinco anos, para calibrar e validar o simulador. / Urban planning is a very important issue to guarantee the sustainable development of modern cities. For this, many aspects must be considered such as the urban growth. Understanding the dynamics of this phenomenon is a prerequisite for modelling and forecasting future trends of urban land use/cover change (LUCC) and its ecological impacts. Cities being complex systems, which involve various actors with different patterns of behaviour, one of the most promising class of urban models designed to simulate and analyze LUCC are based in Multi-Agent System (MAS). Hence, this work describes a proposal based in reactive agents applied in the simulation of urban growth of the city of Bauru/SP, using geographic data, extracted from satellite images, of the occupation and land use in this city in a time span of approximately thirty five years, to calibrate and validate the simulator developed.
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Um modelo de simulação baseado em agentes para análise de cadeias de suprimentoFerreira, Luciano January 2009 (has links)
Uma cadeia de suprimentos é uma rede composta por fornecedores, plantas de manufatura, depósitos, centros de distribuição e varejistas através da qual matériasprimas são adquiridas, transformadas e entregue aos consumidores. A gestão de cadeias de suprimentos (do inglês, Supply Chain Management - SCM) envolve a tomada de decisão nos níveis estratégico, tático e operacional, cujo objetivo é otimizar o desempenho da cadeia . O desenvolvimento de modelos para a avaliação de cadeias de suprimento é uma boa alternativa para estudar a gestão da demanda por produtos, bem como para analisar a efetividade de políticas de gerenciamento. Sistemas multiagentes são apropriados para estudar cadeias de suprimento, pois as diferentes unidades de negócio envolvidas podem ser modeladas como agentes autônomos, assim como suas regras de gerenciamento. Além disso, a modelagem do fluxo de produtos e do fluxo de informações, tais como volume de pedidos e prazos de entrega de um elo da cadeia para outro é facilitada. A análise da literatura especializada da área demonstra que a maior parte dos estudos procura resolver problemas específicos e sem considerar agentes normativos interferindo no comportamento individual de cada ator da cadeia. Este trabalho procura contribuir com o estado da arte da área de gestão de cadeias de suprimento da seguinte forma: (1) propondo um modelo de simulação, composto por agentes genéricos que podem ser facilmente estendidos e utilizados e outros contextos de aplicação, e (2) propondo a utilização dos conceitos de agentes normativos no contexto de cadeias de suprimento. A união dessas áreas (SCM e sistemas multiagentes normativos) aumenta as possibilidades de modelagem de cadeias de suprimento, permitindo a inclusão de entidades externas que normalmente exercem influência na gestão, tais como órgãos do governo, agências reguladoras e instituições eletrônicas. A modelagem da cadeia do biodiesel é apresentada como estudo de caso; os principais resultados obtidos são apresentados e discutidos. / The supply chain is a network of suppliers, factories, warehouses, distribution centers, and retailers through which raw materials are acquired, transformed, and delivered to customers. Supply-chain management (SCM) is the strategic, tactical, and operational decision making that optimizes supply-chain performance. Modeling supply chain is a good way of studying order fulfillments processes and investigating the effectiveness of management policies. Multiagentes models are increasingly being used of this purpose. A multiagent model fits well with the task of simulation supply chain because the businesses involved can be modeled as agents, each with its own inventory rules. It is also easy to model the flow of products down the chain and the flow of information, such as order volumes and lead times, from one organization to another. The analysis of the relevant literature shows that most research works carried out in this area aim to resolve specific problems. Some methodologies and more generic solutions have been proposed, but without considering normative agents which may interfere in the behaviour of actors of the supply chain. This work aims to contribute with the state of the art in the SCM area as follows: (1) building a simulation model to the supply chain context, providing generic agents which may be easily extended and used in other application contexts, and (2) exploiting normative agents in the context of supply chain modeling. The integration of these areas (SCM and normative multi-agent systems) increases the possibilities of supply chain modeling, allowing the inclusion of external entities which normally influence management, such as governmental organizations, regulating agencies and electronic institutions, to give some examples. The modeling of the biodiesel supply chain is presented as a case study; the main results are presented and discussed.
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Simulação de uso de solo urbano utilizando uma abordagem baseada em sistemas multiagentes reativos / Land use simulation based in Multi-Agents Reactive SystemsBastos, André Dias January 2007 (has links)
O planejamento urbano é muito importante para garantir o desenvolvimento sustentável das cidades modernas. Para isso, muitos aspectos devem ser considerados, tais como o crescimento urbano das mesmas, uma vez que, o entendimento das dinâmicas desse fenômeno é um pré-requisito para modelar e prever tendências futuras de mudanças de uso do solo/cobertura da terra (LUCC) e seus impactos ecológicos. Como as cidades são sistemas complexos, que envolvem vários atores com diferentes padrões de comportamento, uma das mais promissoras classes de modelos urbanos designados para simular e analisar mudanças de uso do solo são as baseadas em Sistemas Multiagentes (SMA). Sendo assim, este trabalho descreve uma proposta de abordagem baseada em agentes reativos aplicados na tarefa de simulação de crescimento urbano para a cidade de Bauru/SP, utilizando dados geográficos, extraídos de imagens de satélite, da ocupação e utilização efetiva do uso do solo dessa cidade em um período de aproximadamente trinta e cinco anos, para calibrar e validar o simulador. / Urban planning is a very important issue to guarantee the sustainable development of modern cities. For this, many aspects must be considered such as the urban growth. Understanding the dynamics of this phenomenon is a prerequisite for modelling and forecasting future trends of urban land use/cover change (LUCC) and its ecological impacts. Cities being complex systems, which involve various actors with different patterns of behaviour, one of the most promising class of urban models designed to simulate and analyze LUCC are based in Multi-Agent System (MAS). Hence, this work describes a proposal based in reactive agents applied in the simulation of urban growth of the city of Bauru/SP, using geographic data, extracted from satellite images, of the occupation and land use in this city in a time span of approximately thirty five years, to calibrate and validate the simulator developed.
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