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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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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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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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Modélisation et simulation informatique de l'innovation en médecine : Conception d'un outil d'aide à l'évaluation médico-économique des centres de radiothérapie / Modeling and computer simulation of medical innovation : Design of a aid to medico-economic evaluation of radiotherapy centers toolShtiliyanova, Anastasiya 26 November 2012 (has links)
La thèse porte sur la conception d'un prototype logiciel ayant pour but l'évaluation de l'offre et de la demande pour les centres utilisant des traitements innovants en radiothérapie (hadronthérapie, tomothérapie, stéréotaxie, Cyberknife . . .). Le domaine applicatif visé est le domaine médical. L'étude menée porte également sur la modélisation du comportement du patient face à ces nouvelles technologies, sur leur mise en place et leur utilisation au sein des établissements de santé. Dans notre étude, nous modélisons des facteurs très importants tels que la qualité de vie du patient et sa prise en charge au niveau hospitalier. Nous nous intéressons au coût d'installation et d'entretien des nouvelles technologies. Nous comparons les nouvelles techniques utilisées en radiothérapie avec celles déjà existantes et bien évaluées. La comparaison est effectuée sur plusieurs critères, comprenant les critères médicaux et les critères financiers, dont le remboursement par la sécurité sociale enFrance. L'outil logiciel correspondant est construit en utilisant des techniques de modélisation multi-agents, en intégrant les techniques et le savoir-faire médicaux, ainsi que des modèles épidémiologiques pour caractériser les patients concernés et les thérapies correspondantes dans les centres de radiothérapie. Des méthodes économiques sont implémentées pour évaluer les coûts correspondants. / The main subject of the thesis is the modelling and the implementation of a software prototype for evaluating the supply and the demand for radiotherapy centers using innovative therapies (such as hadrontherapy, tomotherapy, stereotaxy, Cyberknife, . . .). The prototype should be used in the medical domain. The patient behaviour with respect to those new technologies is studied as well as their utilization in health institutions. The study takes into account important factors such as the quality of life of the patient and its treatment in a hospital. The costs of installation and maintainance are included in the tool. The new innovative radiotherapy techniques are compared with the existing ones. The comparison is based on medical and financial criteria, including refunding by the French public health insurance system. The software is based on multi-agent systems, and integrates medical knowledge as well as epidemiologic models for characterizing patients and relevant radio-therapies. Economical methods are also implemented for evaluating the associated costs.
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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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