This thesis discusses the basics of software agents and the way they form the multiagent coalitions. Genetic algorithms are introduced as one of the methods of solving the coalition formation problem. MAPC 2018 competition is introduced, which inspired the final design and implementation of the solution by using the tools described. A demo project was created, in which agents communicate with the MASSim server and gather data which is then used as an input into the genetic algorithm. Its purpose is to assign the agents to the tasks based on the input data, so that the tasks can be accomplished in the most effective manner possible. The results of this algorithm are evaluated in experiments which are focused on the quality of the solutions found as well as the time required for the calculation.

La gestion des flux de trafic aérien (ATFM) cherche à structurer le trafic de manière à réduire la congestion dans l'espace aérien. La congestion étant causée par les avions volant dans les mêmes portions de l'espace aérien en même temps, l'ATFM organise le trafic dans les dimensions spatiales (ex. le réseau de routes) et dans la dimension temporelle (ex. séquencement et fusion de flux d'avions atterrissant ou décollant aux aéroports). L'objectif de cette thèse est de développer une méthodologie qui permet au trafic aérien de s'auto-structurer dans les dimensions spatiales et temporelle quand la demande est élevée. Cette structuration disparait quand la demande diminue. Pour remplir cet objectif, un système multi-agents a été développé, dans lequel les avions coopèrent pour structurer le trafic. Les systèmes multi-agents possèdent plusieurs avantages, incluant une bonne résilience aux perturbations, la résilience étant la capacité du système à modifier ses décisions de manière à retrouver un état stable après l'occurrence d'une perturbation dans son environnement. Dans ce système, trois algorithmes sont implémentés, visant à réduire la com- plexité du trafic de trois manières différentes. Le premier algorithme permet aux agents avions volant sur un réseau de route de réguler leur vitesse de manière à ré- duire le nombre de conflits, un conflit se produisant quand deux avions ne respectent pas les normes de séparation. Le deuxième algorithme permet aux avions de résoudre les conflits quand le trafic n'est pas structuré par un réseau de routes. Le troisième algorithme crée des réseaux de routes locaux temporaires pour structurer le trafic. Les trois algorithmes implémentés dans ce système multi-agents permet de réduire la complexité globale du trafic, qui devient plus simple à gérer pour les contrôleurs aériens. Ces algorithmes sont appliqués à des exemples réalistes et sont capables de structurer le trafic de manière résiliente. / Air Traffic Flow Management (ATFM) aims at structuring traffic in order to reduce congestion in airspace. Congestion being linked to aircraft located at the same position at the same time, ATFM organizes traffic in the spatial dimension (e.g. route network) and in the time dimension (e.g. sequencing and merging of aircraft flows taking off or landing at airports). The objective of this thesis is to develop a methodology that allows the traffic to self-organize in the time and space dimensions when demand is high. This structure disappears when the demand diminishes. In order to reach this goal, a multi-agent system has been developed, in which aircraft cooperate to structure traffic. Multi-agent systems have several advantages, including a good resilience when confronted with disruptive events, resilience being the ability of the system to adapt its decisions in order to get back to a stable state when confronted to a disruption in its environment. In this system, three algorithms have been implemented, aiming at reducing traffic complexity in three different ways. The first algorithm allows aircraft agents flying on a route network to regulate speed in order to reduce the number of conflicts, a conflict occurring when two aircraft do not respect separation norms. The second algorithm allows aircraft to solve conflicts when the traffic is not structured by a route network. The third algorithm creates temporary local route networks allowing to structure traffic. The three algorithms implemented in this multi-agent system allow to decrease overall traffic complexity, which becomes easier to manage by air traffic controllers. This algorithm was applied on realistic examples and was able to structure traffic in a resilient way.

Submitted by Maria Aparecida (cidazen@gmail.com) on 2017-08-21T12:14:23Z No. of bitstreams: 1 Falkner de Arêa Leão Moraes.pdf: 2601896 bytes, checksum: 0fa8b49e3f279d911a70b4f78d9cbe08 (MD5) / Made available in DSpace on 2017-08-21T12:14:23Z (GMT). No. of bitstreams: 1 Falkner de Arêa Leão Moraes.pdf: 2601896 bytes, checksum: 0fa8b49e3f279d911a70b4f78d9cbe08 (MD5) Previous issue date: 2009-02-16 / Lack of security is a constant concern in open distributed systems. Threats are present within environments insecure, uncertain and constantly changing. Due to this problem, many tools for evaluating vulnerabilities of the network as well as for their protection are being developed as techniques for encryption and software systems such as antivirus, firewall and IDS (Intrusion Detection System). Among these, there are IDS systems that are being conceived, designed and implemented, using techniques executed by agents. However, it is necessary to assure security and reliability of exchanged messages inside IDS. For this purpose, this paper proposes a security solution for IDS based on agents. The proposed solution provides a methodology and a secure mechanism for communication among agents, through information protection configuration mechanisms, authentication and authorization, key control and messages persistence using XML. The proposed solution is implemented as an extension to the IDS-NIDIA (Network Intrusion Detection System based on Intelligent Agents), whose architecture has an intelligent agent society that communicate in a cooperative way in a distributed environment. The implementation of the prototype and tests proposed in this work show the applicability of the proposed solution. / A falta de segurança é uma preocupação constante em sistemas distribuídos abertos. Ameaças estão presentes dentro de ambientes inseguros, incertos e que mudam constantemente. Devido a esses problemas, diversas ferramentas para avaliação de vulnerabilidades da rede, bem como para sua proteção, estão sendo desenvolvidas como técnicas de criptografia e softwares como antivírus, firewall e IDS (Intrusion Detection System). Dentre estas, destaca-se Sistemas IDS que estão crescentemente sendo concebidos, projetados e implementados, usando técnicas de segurança executadas por agentes. Entretanto, é necessário que a segurança e a confiabilidade das mensagens trocadas dentro de um sistema IDS sejam asseguradas. Para este fim, este trabalho propõe uma solução segura e confiável para IDS baseada em agentes. A solução propõe estabelecer um esquema de execução e comunicação segura dos agentes através de mecanismos de proteção de informações de configuração, autenticação e autorização, controle de chaves e persistência de mensagens do IDS, utilizando XML. A solução proposta é implementada como uma extensão do IDS-NIDIA (Network Intrusion Detection System based on Intelligent Agents), cuja arquitetura consiste em uma sociedade de agentes inteligentes que se comunicam de forma cooperativa em um ambiente distribuído. A implementação do protótipo e os testes apresentados neste trabalho demonstram a aplicabilidade da solução proposta.

La gestion d’énergie est un sujet de plus en plus important dans notre société. Nous faisons actuellement face à un nombre croissant de problèmes tels que l’épuisement des réserves pétrolières, le réchauffement climatique ou encore la diminution de la qualité de l’énergie (principalement due aux coupures pendant les pics de consommation). Les smartgrids sont une des solutions à ces problèmes. En ajoutant une communication bidirectionnelle et de nouvelles capacités en matière de technologies de l’information et de la communication, il est possible de créer un système autonome de gestion intelligente de l’énergie.Les travaux décrits dans ce mémoire s'intéressent particulièrement à la gestion des microgrids à l'aide de systèmes multi-agents (SMA). Les microgrids sont des réseaux de faibles puissances, composés de petits producteurs d’énergie décentralisés (éventuellement renouvelables) et de consommateurs. Ces réseaux peuvent être reliés (ou non) au réseau global ce qui ajoute à leur complexité. De par leurs complexités et leurs répartitions géographiques, les smartgrids, comme les microgrids, ne peuvent pas être gérés facilement par des systèmes centralisés. Les intelligences artificielles distribuées et plus particulièrement les SMA apparaissent comme un moyen cohérent de résoudre les problèmes liés aux smartgrids.Dans un premier temps, nous avons défini une approche mettant en oeuvre des boucles de rétroaction. Une boucle de rétroaction apparaît dans les systèmes complexes qui peuvent être définis avec plusieurs niveaux d'abstraction. Deux niveaux sont ainsi en interaction. Le niveau micro regroupe un ensemble d'agents ayant des comportements qui, une fois combinés, influeront sur l'état du système. Le niveau macro traite ces influences pour définir un nouvel état du système qui influera sur le comportement des agents du niveau micro. Cette boucle de rétroaction permet de séparer les comportements sur plusieurs niveaux.Cette approche est utilisée pour définir un problème de gestion offre-demande dans un microgrid. Ce problème permet de prendre en compte un ensemble d'objectifs qui sont actuellement traités de manière indépendante. Enfin, une application utilisant un SMA a été développée. Cette approche peut s'intégrer dans ce problème. Elle a pour but d'assurer la stabilité du réseau à tout instant grâce au contrôle de systèmes de stockage.Dans un second temps, un simulateur de réseau électrique permettant le contrôle dynamique des périphériques a été développé. Ce simulateur repose sur trois grands principes. Le premier est une modélisation à base d’agents du simulateur lui-même, pour représenter la complexité des réseaux électriques. Le second principe repose sur l’utilisation du paradigme holonique afin de prendre en compte les multiples niveaux inhérents aux réseaux électriques. Enfin, le troisième principe est inspiré du modelé influence/réaction et propose une technique qui permet de gérer les actions simultanées, éventuellement conflictuelles, au sein des SMA. / Energy management is, nowadays, a subject of uttermost importance. Indeed, we are facing growing concerns such as petroleum reserve depletion, earth global warming or power quality (e.g. avoiding blackouts during peak times). Smart grids is an attempt to solve such problems, by adding to power grids bidirectional communications and ICT capabilities in order to provide an intelligent autonomic management for the grid.This thesis focuses on the management of microgrids thanks to multiagent systems (MAS). Microgrids are low-power networks, composed of small and decentralized energy producers (possibly renewable) and consumers. These networks can be connected to the main grid or islanded, this make them more complex. Due to their complexity and their geographical distribution, smart grids and microgrids can not be easily managed by a centralized system. Distributed artificial intelligences especially MAS appear to be a solution to resolve problems related to smart grids.Firstly we defined an approach implementing feedback loops. These feedback loops exist in complex systems which can be defined with several abstraction levels. Two levels are interacting. The micro-level contains a set of agents owning behaviours that can be combined. The result of the combination imapct the state of the system. The macro-level processes these influences to define a new state of the system which will imapct the agents behaviours at the micro-level.This feedback loop separates behaviours on several levels.This approach is used to defined a demand and supply matching problem in microgrid. This problem afford to manage a set of goals which currently are independently processed. Finally, an application is developed using MAS that ensures grid stability thanks to storage systems. This application was thought to be integrated to the approach detailed above.Secondly, a grid simulator id developed. This simulator allows dynamic control of devices. It is based on three main principles.• An agent-based model of the simulator to represent the complexity of electrical networks. • The use of the holonic paradigm to take into account the multiple levels inherent to power grids. • The use of the influence/reaction model and offers a technology that can manage simultaneous actions, possibly conflicting, in MAS.

Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2018-03-20T21:54:36Z No. of bitstreams: 1 HugoNBR_DISSERT.pdf: 2536238 bytes, checksum: 0dfec391fbd30092d6d905cfe4301c34 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-06-18T17:00:26Z (GMT) No. of bitstreams: 1 HugoNBR_DISSERT.pdf: 2536238 bytes, checksum: 0dfec391fbd30092d6d905cfe4301c34 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-06-18T17:00:34Z (GMT) No. of bitstreams: 1 HugoNBR_DISSERT.pdf: 2536238 bytes, checksum: 0dfec391fbd30092d6d905cfe4301c34 (MD5) / Made available in DSpace on 2018-06-18T17:00:49Z (GMT). No. of bitstreams: 1 HugoNBR_DISSERT.pdf: 2536238 bytes, checksum: 0dfec391fbd30092d6d905cfe4301c34 (MD5) Previous issue date: 2017-08-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / During development of Service-Based Systems (SBS), bad solutions, design or implementation errors can lead to antipatterns that, as opposed to patterns, are bad specifications for recurring problems. Antipatterns result in deviations of functionality during the execution of the system, not adequately satisfying its requirements, which can degrade the Quality of Service (QoS) of the SBS. Its detection and correction are of extreme importance, the emergence of antipatterns may hinder future maintenance and evolution of SBS. As detection method, this work proposes the use of a Multiagent System (MAS), executing search at runtime and notifying the system administrator of QoS drops on the SBS caused by antipatterns. The detection of these antipatterns allows the agents to act in correction the project using the solution recommended by the MAS for the detected problem. The results show that, in the worst cases, the emergence of antipatterns reached extrapolate up to twice the response time of services in a Web Service. The MAS was able to detect, in execution time, the 3 antipatterns studied at work. When adopted, the solutions proposed by the MAS also normalized the response time / Durante o desenvolvimento de Sistemas Baseados em Serviços (SBS), soluções ruins, erros de projeto ou implementação podem conduzir ao surgimento de antipadrões, que em oposição aos padrões, são especificações ruins para problemas recorrentes. Antipadrões acarretam em desvios de funcionalidade durante a execução do sistema, não satisfazendo adequadamente aos seus requisitos, o que pode degradar a Qualidade de Serviço (QoS) de um SBS. Sua detecção e correção são de extrema importância pois o surgimento de antipadrões pode dificultar a manutenção e a futura evolução do SBS. Como método de detecção, este trabalho propõe o uso de um Sistema Multiagente (SMA), realizando buscas em tempo de execução e notificando ao administrador do sistema sobre quedas de QoS no SBS causadas por antipadrões. A detecção desses antipadrões permite a atuação dos agentes na correção do projeto, usando a solução recomendada pelo SMA para o problema detectado. Os resultados mostraram que, nos piores casos, o surgimento de antipadrões chegou a extrapolar em até o dobro de tempo de resposta dos serviços em um Web Service. O SMA foi capaz de detectar, em tempo de execução, os 3 antipadrões estudados no trabalho. Quando adotadas, as soluções propostas pelo SMA também normalizaram o tempo de resposta / 2018-03-20

Made available in DSpace on 2016-08-17T14:53:02Z (GMT). No. of bitstreams: 1 Lindonete Siqueira.pdf: 1117970 bytes, checksum: 5ae44660dd82bbb5725821410930f632 (MD5) Previous issue date: 2006-07-10 / An Intrusion Detection System (IDS) is one tool among several existing ones to provide safety to a computational system. The IDS has the objective of identifying individuals that try to use a system in non-authorized way or those that have authorization but are abusing of their privileges. However, to accomplish the functions correctly an IDS needs to guarantee reliability and availability of its own application. The IDS should provide continuity to its services in case of faults, mainly faults caused by malicious actions. This thesis proposes a fault tolerance mechanism for the Network Intrusion Detection System based on Intelligent Agents Project (NIDIA), an intrusion detection system based on the agents technology. The mechanism uses two approaches: monitoring the system and replication of agents. The mechanism has a society of agents that monitors the system to collect information related to its agents and hosts and to provide an appropriate recovery for each type of detected fault. Using the information that is collected, it is possible: to discover agents that are not active; determine which agents must be replicated and which replication strategy must be used. The replication type depends on the type of each agent and its importance for the system in different moments of processing. Moreover, this monitoring allows to accomplish other important tasks such as load balancing, migration, and detection of malicious agents, to guarantee safety of the proper IDS (self protection). The implementation of the proposed architecture and the illustrated tests demonstrate the viability of the solution. / Entre as diversas ferramentas existentes para prover segurança a um sistema computacional destaca-se o Sistema de Detecção de Intrusão (SDI). O SDI tem como objetivo identificar indivíduos que tentam usar um sistema de modo não autorizado ou que tem autorização, mas abusam dos seus privilégios. Porém, um SDI para realizar corretamente sua função precisa, de algum modo, garantir confiabilidade e disponibilidade a sua própria aplicação. Portanto, o SDI deve dar continuidade aos seus serviços mesmo em caso de falhas, principalmente falhas causadas por açõe maliciosas. Esta dissertação propõe um mecanismo de tolerância a falhas para o Projeto Network Intrusion Detection System based on Intelligent Agents (NIDIA), um sistema de detecção de intrusão baseado na tecnologia de agentes. O mecanismo utiliza duas abordagens: o monitoramento do sistema e a replicação de agentes. O mecanismo possui uma sociedade de agentes que monitora o sistema para coletar informações relacionadas aos seus agentes e hosts e para prover uma recuperação adequada para cada tipo de falha detectada. Usando a informação que é coletada, o sistema pode: descobrir os agentes não ativos; determinar quais os agentes que devem ser replicados e qual estratégia de replicação deve ser usada. A estratégia de replicação depende do tipo de cada agente e da importância do agente para o sistema em diferentes momentos do processamento. Além disso, esse monitoramento também permite realizar outras importantes tarefas tais como balanceamento de carga, migração, e detecção de agentes maliciosos, para garantir a segurança do próprio SDI (self protection). A implementação da arquitetura proposta e os testes realizados demonstram a viabilidade da solução.

The content of this master thesis project is about design and implementation of intelligent client application for Music Player Daemon (MPD), which searches and presents the metadata related to played content. The actual design precedes the theoretical analysis, which includes analysis of agent systems, methods of data classification, web communication protocols and languages for describing HTML document. At the same time is analyzed the MPD server and communication protocol used by clients application. Furthermore, this work describes the current client applications that presents metadata. In the last chapters of the thesis describes the design and implementation of intelligent client. It describes the methods of solution the implementation and solution of problems. Lastest chapters describes the testing result.

This term project desribes simulator of multiagent system implementation. It explains basic concepts of agent and multiagent systems. Simulator is implemented as a separated object, which allows to join various models of environment and agents acting in this environment. Evaluation of several types of agent cooperation behavior is in last section of this project.

L’optimisation de la maintenance industrielle revêt différents aspects suivant les objectifs fixés par l’exploitant industriel. L’objectif le plus courant est la réduction des arrêts et des pannes. Le but est d’assurer une disponibilité élevée de l’équipement. Nous allons plus loin en nous posant la question de l’efficience des coûts de maintenance et de la rentabilité. La réponse donnée ici à cette question provient des résultats d’une fonction de coût associée à une plateforme de simulation basée sur les systèmes multiagents. Le choix du paradigme Agent est motivé par l’utilisation des SMA à d’autres fins de simulation et qu’ils garantissent une forme de souplesse quant à l’évolution du contexte métier. La thèse porte sur un modèle de systèmes multiagents destiné à améliorer la gestion des parcs éoliens à travers la définition d'un ensemble de critères financiers propres à l’exploitant éolien. / Optimization & maintenance in the Industrial sector covers different aspects according to the objectives set by the industrial operator. Their common goal is to reduce downtime and failures. For the windfarm operators the goal is to ensure the wind farms high availibility. We went one step further by asking the question of the efficiency of maintenance costs and the profitability. The answer to this question comes from the results of a cost function associated to a simulation model based on multiagents systems. The choice of the multiagent paradigm is motivated by the use of MAS for other simulation purposes and the fact that they guarantee a kind of flexibility regarding the evolution in a moving business context. This Phd thesis focuses on a multi-agent systems model designed to improve the management of wind farms through the definition of a set of financial criteria specific to the wind farm operators.

<p>For researches in the field of the data mining and machine learning the necessary condition is an availability of various input data set. Now researchers create the databases of such sets. Examples of the following systems are: The UCI Machine Learning Repository, Data Envelopment Analysis Dataset Repository, XMLData Repository, Frequent Itemset Mining Dataset Repository. Along with above specified statistical repositories, the whole pleiad from simple filestores to specialized repositories can be used by researchers during solution of applied tasks, researches of own algorithms and scientific problems. It would seem, a single complexity for the user will be search and direct understanding of structure of so separated storages of the information. However detailed research of such repositories leads us to comprehension of deeper problems existing in usage of data. In particular a complete mismatch and rigidity of data files structure with SDMX - Statistical Data and Metadata Exchange - standard and structure used by many European organizations, impossibility of preliminary data origination to the concrete applied task, lack of data usage history for those or other scientific and applied tasks.</p><p>Now there are lots of methods of data miming, as well as quantities of data stored in various repositories. In repositories there are no methods of DM (data miming) and moreover, methods are not linked to application areas. An essential problem is subject domain link (problem domain), methods of DM and datasets for an appropriate method. Therefore in this work we consider the building problem of ontological models of DM methods, interaction description of methods of data corresponding to them from repositories and intelligent agents allowing the statistical repository user to choose the appropriate method and data corresponding to the solved task. In this work the system structure is offered, the intelligent search agent on ontological model of DM methods considering the personal inquiries of the user is realized.</p><p>For implementation of an intelligent data and metadata exchange repository the agent oriented approach has been selected. The model uses the service oriented architecture. Here is used the cross platform programming language Java, multi-agent platform Jadex, database server Oracle Spatial 10g, and also the development environment for ontological models - Protégé Version 3.4.</p>