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Algoritmos baseados em colônia de formigas para otimização multiobjetivo / Ant colony algorithms for multi-objective optimizationAngelo, Jaqueline da Silva 24 July 2008 (has links)
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Previous issue date: 2008-07-24 / Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior / This dissertation presents the BicriterionAnt, MACS and MONACO Ant Colony algorithms, available in literature, to solve the Multi-Objective Traveling Salesman Problem (MOTSP). The characteristics of the problem and of each
algorithm used are presented. Those algorithms were tested in six bi-objective instances of MOTSP. Changes in the original algorithms were implemented to try to produce better results than the original ones. To validate the results and to measure the quality of the solutions, metrics of performance were used which help to identify the best non-dominated solution sets. / Esta dissertação apresenta os algoritmos BicriterionAnt, MACS e MONACO,
disponíveis na literatura, baseados em colônia de formigas, para resolução do
Problema do Caixeiro Viajante Multiobjetivo (PCVMO). São apresentadas as
características do problema e de cada algoritmo utilizado. Estes algoritmos foram
testados em seis instâncias bi-objetivo do PCVMO. Foram implementadas algumas alterações na estrutura original dos algoritmos na tentativa de produzir resultados melhores do que os algoritmos originais. Para a avaliação dos resultados e medição da qualidade das soluções, foram utilizadas métricas de desempenho que auxiliam na identificação dos melhores conjuntos de soluções não-dominadas.
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Avaliação do uso de meta-heurísticas baseadas no comportamento da natureza em apoio a operações de esclarecimento por aeronaves de asa móvel / Evaluation of the use of metaheuristics based on the behavior of the nature in support of search and reconnaissance operations by rotary-wing aircraftYokoyama, André Muniz 10 May 2016 (has links)
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Previous issue date: 2016-05-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (Capes) / Brazil has an Exclusive Economic Zone that is very extensive and rich, both in its biodiversity as in its mineral resources. In order to exploit these resources and ensure safety for navigation, Brazil must ensure its sovereignty over this part of its territory. For this purpose, Brazil has the Naval Power exercised by the Brazilian Navy. Among the operations carried out by the Navy there are the search and reconnaissance missions, carried out by ships and by naval aircraft. This work is focused on reconnaissance missions carried out by naval aircraft. The main objective is the evaluation of meta-heuristics for the development of an application that can generate optimized routes for aircraft in the missions, attending the requirements of the Brazilian Navy. This work presents the methods developed based on two nature inspired meta-heuristics, for the elaboration of optimized routes for aircraft. The method is complying with two main constraints for these missions: checkpoints (targets) mobility and the limit of aircraft autonomy. It also presents the results of tests performed with the methods developed in this work and a general evaluation of their performance. / O Brasil possui uma área de Zona Econômica Exclusiva muito extensa e muito rica, tanto na sua biodiversidade como em recursos minerais. Porém, para poder explorar estas riquezas e garantir a segurança para a navegação destas águas o Brasil precisa assegurar sua soberania sobre esta parte de seu território. Para isso conta com o Poder Naval exercido pela Marinha do Brasil, que entre as operações por ela realizadas estão as missões de busca e esclarecimento, tanto por embarcações, como por aeronaves embarcadas. Este trabalho tem seu foco nas operações de esclarecimento por aeronaves embarcadas, tendo como objetivo principal a avaliação de meta-heurísticas para a elaboração de uma aplicação capaz de gerar rotas otimizadas para as aeronaves, em missões de esclarecimento, as quais atendam as necessidades da Marinha do Brasil. Neste trabalho, são apresentados os métodos desenvolvidos com base em duas meta-heurísticas, baseadas na natureza, para a elaboração de rotas otimizadas para as aeronaves, atendendo a duas restrições fundamentais em missões de esclarecimento aéreo, a mobilidade dos pontos de checagem (alvos) e o limite de autonomia das aeronaves. Também são apresentados os resultados dos testes realizados com os métodos desenvolvidos e uma avaliação geral dos seus desempenhos.
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Utilisation de la conduite coopérative pour la régulation de trafic dans une intersection / Using the technology of cooperative driving for the traffic control at isolated intersectionWu, Jia 20 July 2011 (has links)
L’objectif de ce travail est d’exploiter les potentialités offertes par la conduite coopérative afin de fluidifier le trafic au niveau des intersections isolées. Pour ce faire, nous avons proposé un nouveau système de régulation au sein des intersections en s’inspirant du principe de l’intersection autonome. Nous avons appelé notre système : SVAC (système du véhicule-actionneur coopératif). Il repose sur la possibilité des échanges d’information entre le véhicule et son environnement de conduite.Le SVAC permet une régulation plus précise du trafic puisqu’il se base sur les requêtes de droit de passage envoyées par les véhicules réellement présents dans l’intersection. En outre, grâce à la signalisation à bord, la régulation consiste à définir les séquences de passage des véhicules, ce qui permet de personnaliser la signalisation. Le gain de précision soulève plusieurs obstacles. D’une part, nous nous heurtons systématiquement à l’absence de modèles mathématiques permettant d’aborder le problème. D’autre part, la simple énumération des séquences implique une explosion combinatoire, ce qui ne convient pas à l’application temps-réelle de la régulation des intersections. Pour s’affranchir des deux problématiques nous avons utilisé les réseaux de Petri P-temporisés. Le modèle nous a permis de décrire sous la forme d’équations mathématiques les compteurs des différents évènements observés par les véhicules. Deux objectifs de régulation ont été dégagés après avoir déduit le temps moyen d’attente basé sur la formule de Little. Le premier consiste à vider les intersections au plus tôt. Nous avons proposé un algorithme de programmation dynamique et deux heuristiques. La première heuristique est directement issue de l’analyse des propriétés du problème posé. La deuxième est basée sur l’algorithme de colonies de fourmis. En effet, le problème défini est un cas particulier du problème du voyageur de commerce. Le deuxième objectif de régulation consiste à minimiser instantanément la longueur de la file d’attente. Dans ce cadre, nous avons supposé le fonctionnement à vitesse maximale du réseau de Petri. L’utilisation des contraintes sur les ressources nous a permis de définir des règles simples de régulation en utilisant le mapping.Dans ce mémoire, nous avons utilisé la simulation microscopique basée sur les lois de poursuite pour s’approcher du comportement de conduite. La simulation a servi pour la comparaison des différentes approches proposées dans ce mémoire avec les régulateurs adaptatifs et les intersections autonomes. Dans tous les cas notre approche se distingue par un gain de capacité, ce qui nous a encouragé de reproduire le SVAC à travers un prototype de robots. Cette maquette montre la faisabilité du système au moins pour des applications industrielles. / The aim of this work is to benefit from the potential of the cooperative driving in order to optimize the traffic throughput at isolated intersections. To achieve this objective, we have proposed a new traffic control system for isolated intersections: Cooperative Vehicle-Actuation Signalization (CVAS). The concept of this new system is based on the assumption of the ability of exchanging information between each vehicle and the surrounding vehicles or the nearby infrastructure.The system allows more precise control of the traffic since it determines the right-of-way of each vehicle according to its corresponding data sent by the embedded wireless device. The right-of-way is displayed to the driver by means of the onboard signalization. The control system determines the sequence of the vehicles to be directed through the intersection. For the sake of benefiting the improvement brought by the new system, we face several challenges. On the one hand, we are confronted with the absence of a mathematical model to address the control problem. On the other hand, despite the fact that the optimal passing sequence of vehicles can be found by the simple enumeration of all feasible sequences, the exhaustive search does not fulfill the requirements of the real-time application. To overcome these two problems, we seek help from the P-timed Petri nets. This mathematical modeling tool is able to describe the events observed by the position markers in the form of mathematical equations. Two different objectives of the control have been derived from the Little's formula. The first one aims to minimize the maximum exit time of vehicles present in the intersection. An algorithm of dynamic programming and two heuristics have been proposed to achieve this objective. The first heuristic is based on the analysis of the properties of the control problem. The second heuristic is based on the analogy between the dealt problem and the problem of Traveling Salesman Problem, which can be solved successfully by the algorithm of ant colony system. The second objective of the control is to instantly minimize the queue length. A protocol of relaying the right of way has been determined from the assumption of a Petri net that operates at its maximum speed. This simple protocol of control can be extended to all possible layouts of the isolated intersections by using the technique of “mapping”.In this work, a microscopic model (car-following model) is used to simulate the driving behavior. The simulations show that the CVAS system outperforms the other systems which are popularly used at present. It is even better than some innovative systems based on the technology of the cooperative driving. The good results encouraged us to replicate the system under real conditions through a prototype of NXT robots. The tests of this prototype prove the feasibility of the system at least for industrial applications.
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Bio-inspired Approaches for Informatio Dissemination in Ad hon Networks / Approches Bio-inspirées pour diffusion de l’information dans les réseaux ad hocMedetov, Seytkamal 19 December 2014 (has links)
La dissémination d’information dans les réseaux VANET est une opération fondamentale pour la sécurité routière. Il est dès lors nécessaire de concevoir et mettre en oeuvre des algorithmes efficaces et adaptatifs pour la dissémination d’informations sélectives et pertinentes.Dans ce travail, des approches Bio-inspirées sont proposées, à partir des comportements auto-organisés des essaims comme les colonies de fourmis et d’abeilles. Ces approches visent à fournir à chaque véhicule des informations en provenance de son environnement et alerter les conducteurs. Dans la première approche, le système de communication direct et indirect des fourmis est utilisé. Les fourmis partagent les informations sur les sources de nourriture avec des membres de la colonie en sécrétant la phéromone sur leurs chemins. La deuxième approche est inspirée par le système de communication des abeilles. Les abeilles partagent les informations à propos des sources de nourriture avec les autres membres de la ruche par des messages spécifiques, selon l’importance de ces sources.Une nouvelle mesure de "pertinence" associée aux messages est définie, par analogie à la sécrétion des phéromones des fourmis et au niveau de l’intensité des messages pour les abeilles, pour disséminer des informations de sécurité dans une zone géographique. Les simulations sont effectuées en utilisant le simulateur NS2 pour mesurer l’efficacité des approches proposées sous différentes conditions, en particulier en termes de densités et vitesses des véhicules. / Information dissemination in Vehicular Ad hoc Networks (VANETs) is a fundamental operation to increase the safety awareness among vehicles on roads. Thus, the design and implementation of efficient and scalable algorithms for relevant information dissemination constitutes a major issue that should be tackled.In this work, bio-inspired information dissemination approaches are proposed, that use self-organization principles of swarms such as Ant and Honey Bee colonies. These approaches are targeted to provide each vehicle with the required information about its surrounding and assist drivers to be aware of undesirable road conditions. In the first approach, Ant’s direct and indirect communication systems are used. Ants share information about food findings with colony members by throwing pheromone on the returning to the nest. The second, an RSU-based approach is inspired by the Bee communication system. Bees share profitable food sources with hive-mates in their hive by specific messages.A “relevance” value associated to the emergency messages is defined as an analogue to pheromone throwing in Ant colony, and as an analogue to profitability level in Bee colony, to disseminate safety information within a geographical area. Simulations are conducted using NS2 network simulator and relevant metrics are evaluated under different node speeds and network densities to show the effectiveness of the proposed approaches.
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Deterministic Scheduling Of Parallel Discrete And Batch ProcessorsVenkataramana, M 07 1900 (has links)
Scheduling concerns the allocation of limited resources to tasks over time. In manufacturing systems, scheduling is nothing but assigning the jobs to the available processors over a period of time. Our research focuses on scheduling in systems of parallel processors which is challenging both from the theoretical and practical perspectives. The system of parallel processors is a common occurrence in different types of modern manufacturing systems such as job shop, batch shop and mass production.
A variety of important and challenging problems with realistic settings in a system of parallel processors are considered. We consider two types of processors comprising discrete and batch processors. The processor which produces one job at a time is called a discrete processor. Batch processor is a processor that can produce several jobs simultaneously by keeping jobs in a batch form which is commonly seen in semiconductor manufacturing, heat treatment operations and also in chemical processing industries. Our aim is to develop efficient solution methodologies (heuristics/metaheuristics) for three different problems in the thesis. The first two problems consider the objective of minimizing total weighted tardiness in cases of discrete and batch processors where customer delivery time performance is critical. The third problem deals with the objective of minimizing the total weighted completion time in the case of batch processors to reduce work-in-process inventory.
Specifically, the first problem deals with the scheduling of parallel identical discrete processors to minimize total weighted tardiness. We develop a metaheuristic based on
Ant Colony Optimization(ACO) approach to solve the problem and compare it with the available best heuristics in the literature such as apparent tardiness cost and modified due date rules. An extensive experimentation is conducted to evaluate the performance of the ACO approach on different problem sizes with varied tardiness factors. Our experimentation shows that the proposed ant conony optimization algorithm yields promising results as compared to the best of the available heuristics.
The second problem concerns with the scheduling of jobs to parallel identical batch processors for minimizing the total weighted tardiness. It is assumed that the jobs are incompatible in respect of job families indicating that jobs from different families cannot be processed together. We decompose the problem into two stages including batch formation and batch scheduling as in the literature. Ant colony optimization based heuristics are developed in which ACO is used to solve the batch scheduling problem. Our computational experimentation shows that the proposed five ACO based heuristics perform better than the available best traditional dispatching rule called ATC-BATC rule.
The third scheduling problem is to minimize the total weighted completion time in a system of parallel identical batch processors. In the real world manufacturing system, jobs to be scheduled come in lots with different job volumes(i.e number of jobs) and priorities. The real settings of lots and high batch capacity are considered in this problem. This scheduling problem is formulated as a mixed integer non-linear program. We develop a solution framework based on the decomposition approach for this problem. Two heuristics are proposed based on the proposed decomposition approach and the performance of these heuristics is evaluated in the cases of two and three batch processors by comparing with the solution of LINGO solver.
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Shape Optimization Using A Meshless Flow Solver And Modern Optimization TechniquesSashi Kumar, G N 11 1900 (has links)
The development of a shape optimization solver using the existing Computational Fluid
Dynamics (CFD) codes is taken up as topic of research in this thesis. A shape optimizer
was initially developed based on Genetic Algorithm (GA) coupled with a CFD solver
in an earlier work. The existing CFD solver is based on Kinetic Flux Vector Splitting
and uses least squares discretization. This solver requires a cloud of points and their
connectivity set, hence this CFD solver is a meshless solver. The advantage of a meshless
solver is utilised in avoiding re-gridding (only connectivity regeneration is required) after each shape change by the shape optimizer. The CFD solver is within the optimization loop, hence evaluation of CFD solver after each shape change is mandatory. Although the earlier shape optimizer developed was found to be robust, but it was taking enoromous amount of time to converge to the optimum solution (details in Appendix). Hence a new evolving method, Ant Colony Optimization (ACO), is implemented to replace GA. A shape optimizer is developed coupling ACO and the meshless CFD solver. To the best of the knowledge of the present author, this is the first time when ACO is implemented for aerodynamic shape optimization problems. Hence, an exhaustive validation has become mandatory. Various test cases such as regeneration problems of
(1) subsonic - supersonic nozzle with a shock in quasi - one dimensional flow
(2) subsonic - supersonic nozzle in a 2-dimensional flow field
(3) NACA 0012 airfoil in 2-dimensional flow and
(4) NACA 4412 airfoil in 2-dimensional flow
have been successfully demonstrated. A comparative study between GA and ACO at
algorithm level is performed using the travelling salesman problem (TSP). A comparative study between the two shape optimizers developed, i.e., GA-CFD and ACO-CFD is carried out using regeneration test case of NACA 4412 airfoil in 2-dimensional flow. GA-CFD performs better in the initial phase of optimization and ACO-CFD performs
better in the later stage. We have combined both the approaches to develop a hybrid
GA-ACO-CFD solver such that the advantages of both GA-CFD and ACO-CFD are retained with the hybrid method. This hybrid approach has 2 stages, namely,
(Stage 1) initial optimum search by GA-CFD (coarse search), the best members from
the optimized solution from GA-CFD are segregated to form the input for the fine search by ACO-CFD and
(Stage 2) final optimum search by ACO-CFD (fine search).
It is observed that this hybrid method performs better than either GA-CFD or ACO-
CFD, i.e., hybrid method attains better optimum in less number of CFD calls. This
hybrid method is applied to the following test cases:
(1) regeneration of subsonic-supersonic nozzle with shock in quasi 1-D flow and
(2) regeneration of NACA 4412 airfoil in 2-dimensional flow.
Two applications on shape optimization, namely,
(1) shape optimization of a body in strongly rotating viscous flow and
(2) shape optimization of a body in supersonic flow such that it enhances separation of binary species, have been successfully demonstrated using the hybrid GA-ACO-CFD method. A KFVS based binary diffusion solver was developed and validated for this purpose.
This hybrid method is now in a state where industrial shape optimization applications
can be handled confidently.
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Autonomic and Energy-Efficient Management of Large-Scale Virtualized Data CentersFeller, Eugen 17 December 2012 (has links) (PDF)
Large-scale virtualized data centers require cloud providers to implement scalable, autonomic, and energy-efficient cloud management systems. To address these challenges this thesis provides four main contributions. The first one proposes Snooze, a novel Infrastructure-as-a-Service (IaaS) cloud management system, which is designed to scale across many thousands of servers and virtual machines (VMs) while being easy to configure, highly available, and energy efficient. For scalability, Snooze performs distributed VM management based on a hierarchical architecture. To support ease of configuration and high availability Snooze implements self-configuring and self-healing features. Finally, for energy efficiency, Snooze integrates a holistic energy management approach via VM resource (i.e. CPU, memory, network) utilization monitoring, underload/overload detection and mitigation, VM consolidation (by implementing a modified version of the Sercon algorithm), and power management to transition idle servers into a power saving mode. A highly modular Snooze prototype was developed and extensively evaluated on the Grid'5000 testbed using realistic applications. Results show that: (i) distributed VM management does not impact submission time; (ii) fault tolerance mechanisms do not impact application performance and (iii) the system scales well with an increasing number of resources thus making it suitable for managing large-scale data centers. We also show that the system is able to dynamically scale the data center energy consumption with its utilization thus allowing it to conserve substantial power amounts with only limited impact on application performance. Snooze is an open-source software under the GPLv2 license. The second contribution is a novel VM placement algorithm based on the Ant Colony Optimization (ACO) meta-heuristic. ACO is interesting for VM placement due to its polynomial worst-case time complexity, close to optimal solutions and ease of parallelization. Simulation results show that while the scalability of the current algorithm implementation is limited to a smaller number of servers and VMs, the algorithm outperforms the evaluated First-Fit Decreasing greedy approach in terms of the number of required servers and computes close to optimal solutions. In order to enable scalable VM consolidation, this thesis makes two further contributions: (i) an ACO-based consolidation algorithm; (ii) a fully decentralized consolidation system based on an unstructured peer-to-peer network. The key idea is to apply consolidation only in small, randomly formed neighbourhoods of servers. We evaluated our approach by emulation on the Grid'5000 testbed using two state-of-the-art consolidation algorithms (i.e. Sercon and V-MAN) and our ACO-based consolidation algorithm. Results show our system to be scalable as well as to achieve a data center utilization close to the one obtained by executing a centralized consolidation algorithm.
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PID tuning with Ant Colony Optimization (ACO) : A framework for a step response based tuning algorithmBjörk, Carl Johan January 2018 (has links)
The building automation industry lacks an affordable, simple, solution for autonomous PID controller tuning when overhead variables fluctuate. In this project, requested by Jitea AB, a solution was developed, utilising step response process modelling, numerical integration of first order differential equations, and Ant Colony Optimization (ACO). The solution was applied to two control schemes; simulated outlet flow from a virtual water tank, and the physical air pressure in the ventilation system of a preschool in Sweden. An open-loop step response provided the transfer function in each case, which, after some manipulation, could be employed to predict the performance of any given set of PID parameters, based on a weighted cost function. This prediction model was used in ACO to find optimal settings. The program was constructed in both Structured Control Language and Structured Text and documented in an approachable way. The results showed that the program was, in both cases, able to eliminate overshoot and retain the settling time (with a slightly raised rise time) achieved with settings tuned per the current methods of Jitea AB. Noise and oscillations present in the physical system did not appear to have any major negative influence on the tuning process. The program performed above Jitea AB’s expectation, and will be tested in more scenarios, as it showed promise. Autonomous implementation could be of societal benefit through increased efficiency and sustainability in a range of processes. In future studies, focus should be on improving the prediction model, and further optimising the ACO variables. / Byggnadsautomationsbranschen saknar en kostnadseffektiv lösning för att autonomt trimma in PID-regulatorer när överordnade variabler fluktuerar. I detta (av Jitea AB beställda) arbete, utvecklades en lösning baserad på stegsvarsmodellering, numerisk integration av första gradens ordinära differentialekvationer och myrkolonisoptimering (ACO). Lösningen applicerades i två regleringsfall; en simulerad utloppsventil från en virtuell vattentank, och det fysiska lufttrycket i ventilationssystemet på en förskola i Sverige. Ett stegsvar med öppen slinga gav en överföringsfunktion i respektive fall, som efter viss manipulering kunde nyttjas för att förutspå prestandan för en uppsättning PID-parametrar baserat på en samlad, viktad kostnadsfunktion. Predikteringsmodellen implementerades i ACO för att finna optimala parametrar. Programmet konstruerades i Structured Control Language och Structured Text, och dokumenterades på ett pedagogiskt sätt. Resultaten visade att programmet (i båda fallen) klarade att eliminera översläng med bibehållen stabiliseringstid (och något förskjuten stigningstid) jämfört med Jitea AB:s existerande trimningsmetod. Signalbrus och oscillationer i det fysiska systemet verkade inte ha någon avsevärd negativ inverkan på trimningsprocessen. Programmet presterade över Jitea AB:s förväntan, och kommer (med tanke på de lovande resultaten) fortsatt att testas i fler scenarion. Implementation av en autonom version skulle kunna innebära flera samhälleliga förmåner i form av ökad verkningsgrad och hållbarhet i en rad processer. I framtida studier bör fokus läggas på att ytterligare förbättra prediktionsmodellen, samt att vidare utforska de optimala myrkolonisvariablerna.
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Sistemas inteligentes aplicados à coordenação da proteção de sistemas elétricos industriais com relés digitais. / The application of intelligent systems in industrial power systems protection coordination using digital relays.Eduardo Lenz Cesar 07 August 2013 (has links)
Atualmente existem diferentes ferramentas computacionais para auxílio nos
estudos de coordenação da proteção, que permitem traçar as curvas dos relés, de
acordo com os parâmetros escolhidos pelos projetistas. Entretanto, o processo de
escolha das curvas consideradas aceitáveis, com um elevado número de
possibilidades e variáveis envolvidas, além de complexo, requer simplificações e
iterações do tipo tentativa e erro. Neste processo, são fatores fundamentais tanto a
experiência e o conhecimento do especialista, quanto um árduo trabalho, sendo que
a coordenação da proteção é qualificada pela IEEE Std. 242 como sendo mais uma
arte do que uma ciência. Este trabalho apresenta o desenvolvimento de um
algoritmo genético e de um algoritmo inspirado em otimização por colônia de
formigas, para automatizar e otimizar a coordenação da função de sobrecorrente de
fase de relés digitais microprocessados (IEDs), em subestações industriais. Seis
estudos de caso, obtidos a partir de um modelo de banco de dados, baseado em um
sistema elétrico industrial real, são avaliados. Os algoritmos desenvolvidos geraram,
em todos os estudos de caso, curvas coordenadas, atendendo a todas as restrições
previamente estabelecidas e as diferenças temporais de atuação dos relés, no valor
de corrente de curto circuito trifásica, apresentaram-se muito próximas do
estabelecido como ótimo. As ferramentas desenvolvidas demonstraram
potencialidade quando aplicadas nos estudos de coordenação da proteção, tendo
resultados positivos na melhoria da segurança das instalações, das pessoas, da
continuidade do processo e do impedimento de emissões prejudiciais ao meio
ambiente. / Nowadays there are several computational tools applied to the protection
coordination studies, which allow observe the curves of the relays, according to the
parameters chosen by the designers. However, the process of choosing the curves
considered acceptable, with a great number of possibilities and variables involved, is
difficult and, moreover, requires simplifications and some trial and error iterations. In
this process, the key factors are the expert experience and knowledge as well as a
hard work. The protection coordination is described by IEEE Std. 242 as more of an
art than a science. This paper presents the development of a genetic algorithm and
an algorithm based on an ant colony optimization to automate and optimize the
coordination of overcurrent curves using intelligent electronic devices (IEDs) in
industrial substations. Six case studies, obtained from a database model based on
an actual industrial electrical system, were evaluated. The developed algorithms
generated, in all case studies, coordinated curves, complying with all previous
established restrictions. The temporal differences of the curves, at three-phase short
circuit current values, were very close to the set as optimal. The developed tools are
a valuable contribution to the protection coordination studies, improving the safety of
the equipment and the people, the process reliability and the prevention of harmful
emissions to the environment.
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Implementação e avaliação de abordagens heurísticas para o problema do roteamento de cabos em painéis elétricos / Implementation and evaluation of heuristic approaches for the cable routing problem in electrical panelsIttner, Alexandre Erwin 24 August 2010 (has links)
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Previous issue date: 2010-08-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This dissertation presents a research work on the Cable Routing Problem in Electrical Panels and its resolution by computational means. Strictly, this work shows a formal definition for the problem, elaborates on the available computational approaches, and suggests several algorithms for its resolution. At last, an application developed using the proposed algorithms is described, yielding good results for the problem instances typically found in the industry. / Esta dissertação apresenta um estudo sobre as características do Problema do Roteamento de Cabos em Painéis Elétricos e sua solução por meios computacionais. Especificamente, este trabalho apresenta uma definição formal para o problema, descreve as abordagens computacionais disponíveis e propõe uma série de algoritmos para sua solução. Por fim, descreve-se um aplicativo
desenvolvido empregando os algoritmos propostos que permite a obtenção de bons resultados para as instâncias deste problema tipicamente encontradas na indústria.
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