The aim of this master thesis is optimization of the rotor in the terms of efficiency. An analysis of the effects of rotor parameters is performed by RMXPRT. A genetic algorithm is created to find the optimal solution. Solutions are evaluated and adjusted according to the results. Measurements on the actual machine are performed and evaluated to verify the functionality of the simulation models.

Nas últimas décadas, considerável evidência tem sido direcionada no desenvolvimento de métodos computacionais que analisam os comportamentos não lineares das estruturas. O método da corda é considerado o tipo de método de seguimento de trajetórias que possui a técnica mais comum e versátil para analisar tais comportamentos não lineares. No entanto, testes realizados pelos autores concluem que tais métodos ainda apresentam algumas dificuldades quando as estruturas possuem formas complexas e comportamentos fortemente não lineares. Devido a isso, o objetivo do trabalho em questão é acrescentar duas modificações ao método da corda, a fim de desenvolver um modelo mais seguro e estável. A esses métodos, inclui-se (i) uma equação alternativa para o passo previsor, que tornará o método mais estável ao ultrapassar pontos críticos; e (ii) um parâmetro de controle, que através do conceito de soma dos comprimentos de corda, é chamado de método da corda acumulado. Ao final, por consequência destas alterações, um procedimento mais robusto para o método da corda é obtido. Sua validação é apresentada, pelos autores, através de exemplos utilizando estruturas treliçadas (bidimensionais e tridimensionais) em um programa de simulação numérica desenvolvida. / In the last decades, a considerable effort has been directed to develop of computational methods to analyze the nonlinear behavior of structures. The arc-length method is considered the type of path following method which have the most common and versatile techniques for analyzing such nonlinear behaviors. Nevertheless, tests performed by the authors conclude that such methods present some difficulties when the structures possess complex shapes and strongly nonlinear behaviors. Due to this, the purpose of the present work is to add two amendments to the arc-length method, in order to develop a model safer and more stable. In such methods, it is included (i) an alternative equation for the predictor step, that will make the method most stable to overcoming critical points, and (ii) a control parameter, through the concept of sum of the arc length up to now, referred to as accumulated arc-length method. By the end, as a result of these modifications, a more robust procedure for the method of the string is obtained. And its validation is presented by the authors through examples using truss structures in a two-dimensional and three-dimensional numerical simulation program developed.

Genetic algorithm has been widely used in different areas of optimization problems. Ithas been combined with renewable energy domain, photovoltaic system, in this thesis.To participate and win the solar boat race, a control program is needed and C++ hasbeen chosen for programming. To implement the program, the mathematic model hasbeen built. Besides, the approaches to calculate the boundaries related to conditionhave been explained. Afterward, the processing of the prediction and real time controlfunction are offered. The program has been simulated and the results proved thatgenetic algorithm is helpful to get the good results but it does not improve the resultstoo much since the particularity of the solar driven boat project such as the limitationof energy production

The realization of planning, design, construction, operation and maintenance of water supply systems pictures one of the largest infrastructure projects of municipalities / water distribution networks should be designed very meticulously. Genetic algorithm is an optimization method that is based on natural evolution and is used for the optimization of water distribution networks. Genetic algorithm is comprised of operators and the operators affect the performance of the algorithm. Although these operators are related with parameters, not much attention has been given for the determination of these parameters for this specific field of water distribution networks. This study represents a novel methodology, which investigates the parameters of the algorithm for different networks. The developed computer program is applied to three networks. Two of these networks are well known examples from the literature / the third network is a pressure zone of Ankara water distribution network. It is found out that, the parameters of the algorithm are related with the network, the case to be optimized and the developed computer program. The pressure penalty constant value varied depending on the pipe costs and the network characteristics. The mutation rate is found to vary in a range of [0.0075 &ndash / 0.0675] for three networks. Elitism rate is determined as the minimum value for the corresponding population size. Crossover probability is found to vary in a range of [0.5 &ndash / 0.9]. The methodology should be applied to determine the appropriate parameter set of genetic algorithm for each optimization study. Using the method described, fairly well results are obtained.

Application of optimization techniques for determining the optimal operating policy for reservoirs is a major title in water resources planning and management. Genetic algorithms, ruled by evolution techniques, have become popular for solving optimization problems in diversified fields of science. The main aim of this research was to explore the efficiency and effectiveness of the applicability of genetic algorithm in optimization of multi-reservoirs. A computer code has been constructed for this purpose and verified by means of a reference problem with a known global optimum. Three reservoirs in the Colorado River Storage Project were optimized for maximization of energy production. Besides, a real-time approach utilizing a blend of online and a posteriori data was proposed. The results achieved were compared to the real operational data and genetic algorithms were found to be effective, competitive and can be utilized as an alternative technique to other traditional optimization techniques.

An aerodynamic design and optimization tool for wind turbines is developed by using both Blade Element Momentum (BEM) Theory and Genetic Algorithm. Turbine blades are optimized for the maximum power production for a given wind speed, a rotational speed, a number of blades and a blade radius. The optimization variables are taken as a fixed number of sectional airfoil profiles, chord lengths, and twist angles along the blade span. The airfoil profiles and their aerodynamic data are taken from an airfoil database for which experimental lift and drag coefficient data are available. The BEM analysis tool developed is first validated with the experimental data for low wind speeds. A 100 kW wind turbine, which is used in the validation, is then optimized. As a result of the optimization, the power production is improved by 40 to 80 percent. The optimization methodology is then employed to design a 1MW wind turbine with a 25m radius.

In this thesis work, minimization of platform-based coupling between the antennas of two VHF radios on an aircraft platform and two HF radios on a ship platform is aimed. For this purpose / an optimal antenna placement, which yields minimum average coupling between the antennas over the whole frequency band of operation is determined for each platform. Two important global optimization techniques, namely Genetic Algorithm Optimization and Particle Swarm Optimization, are used in determination of these optimal antenna placements. Aircraft &amp / ship platforms and antennas placed on them are modeled based on their real electrical and physical properties in CST &ndash / MWS (Microwave Studio) simulation tool. For each platform, antenna placements and coupling results determined by two different optimization techniques and performances of these optimization techniques are compared with each other. At the end of this thesis work / for each platform, far-field radiation pattern performances of the antennas at their optimal places are analyzed in terms of directivity and coverage.

Nas últimas décadas, considerável evidência tem sido direcionada no desenvolvimento de métodos computacionais que analisam os comportamentos não lineares das estruturas. O método da corda é considerado o tipo de método de seguimento de trajetórias que possui a técnica mais comum e versátil para analisar tais comportamentos não lineares. No entanto, testes realizados pelos autores concluem que tais métodos ainda apresentam algumas dificuldades quando as estruturas possuem formas complexas e comportamentos fortemente não lineares. Devido a isso, o objetivo do trabalho em questão é acrescentar duas modificações ao método da corda, a fim de desenvolver um modelo mais seguro e estável. A esses métodos, inclui-se (i) uma equação alternativa para o passo previsor, que tornará o método mais estável ao ultrapassar pontos críticos; e (ii) um parâmetro de controle, que através do conceito de soma dos comprimentos de corda, é chamado de método da corda acumulado. Ao final, por consequência destas alterações, um procedimento mais robusto para o método da corda é obtido. Sua validação é apresentada, pelos autores, através de exemplos utilizando estruturas treliçadas (bidimensionais e tridimensionais) em um programa de simulação numérica desenvolvida. / In the last decades, a considerable effort has been directed to develop of computational methods to analyze the nonlinear behavior of structures. The arc-length method is considered the type of path following method which have the most common and versatile techniques for analyzing such nonlinear behaviors. Nevertheless, tests performed by the authors conclude that such methods present some difficulties when the structures possess complex shapes and strongly nonlinear behaviors. Due to this, the purpose of the present work is to add two amendments to the arc-length method, in order to develop a model safer and more stable. In such methods, it is included (i) an alternative equation for the predictor step, that will make the method most stable to overcoming critical points, and (ii) a control parameter, through the concept of sum of the arc length up to now, referred to as accumulated arc-length method. By the end, as a result of these modifications, a more robust procedure for the method of the string is obtained. And its validation is presented by the authors through examples using truss structures in a two-dimensional and three-dimensional numerical simulation program developed.

The AOE Accumulated Ocean Energy Inc. (AOE) wave energy converter (WEC) is a cascaded pneumatic system, in which air is successively compressed through three point absorber devices on the way to shore; this air is then used to drive an electricity generator. To better quantify the performance of this device, this thesis presents a dynamically coupled model architecture of the AOE WEC, which was developed using the finite element solver ProteusDS and MATLAB/Simulink. This model is subsequently applied for the development and implementation of control in the AOE WEC. At each control stage, comprehensive power matrix data is generated to assess power production as a function of control complexity. The nature of the AOE WEC presented a series of novel challenges, centered on the significant residency time of air within the power take-off (PTO). As a result, control implementation was broken into two stages: passive and active control. The first stage, passive control, was realized as an optimization of eight critical PTO parameters with the objective of maximizing exergy output. After only 15 generations, the genetic algorithm optimization led to an increase of 330.4% over an initial, informed estimate of the optimal design, such that the annually-averaged power output was 29.37 kW. However, a disparity in power production between low and moderate energy sea-states was identified, which informed the development of an active control strategy for the increase of power production in low energy sea-states. To this aim, a recirculation-based control strategy was developed, in which three accumulator tanks were used to selectively pressurize and de-pressurize the piston at opportune times, thereby increasing the continuity of air throughput. Under the influence of active control, sea-states with significant wave heights between 0.75 m – 1.75 m, which on average encompass 55.93% of the year at the Amphitrite Bank deployment location, saw a 16.3% increase in energy production. / Graduate / 2018-08-18

As tecnologias da informação, telecomunicações e mobilidade aliadas às mudanças econômicas e sociais acarretaram uma grande reestruturação da indústria. Entre estas mudanças, verifica-se um maior nível de descentralização e especialização das unidades produtivas, o aumento da automação dos processos e, em conseqüência, uma maior quantidade e complexidade nas interações de seus sub-sistemas. De forma a lidar com esta complexidade e facilitar o estudo e projeto de novos sistemas, faz-se necessário o uso de modelos, que são analisados por exemplo, através de simulação. Entre elas destaca-se a simulação distribuída, a qual trata da evolução de situações/cenários do sistema em computadores fisicamente dispersos, conectados através de uma rede de comunicação, visando, por exemplo, a redução do tempo de simulação, a simulação de grandes modelos(composto por muitos elementos), maior tolerânica a falhas e mesmo a distribuição geográfica. Visando contribuir para uma maior aplicabilidade das técnicas de modelagem e simulação, em especial a distribuída, propõe-se nesta tese (1) um novo método para a modelagem hierárquica de sistemas produtivos; e (2) um novo algoritmo para a sincronização da evolução do tempo de simulação de diferentes simuladores interagindo através de redes de comunicação (LAN, WAN). No método de modelagem proposto, utiliza-se uma abordagem top-down para a decomposição do sistema, partindo-se de um nível de abstração para um de maior detalhamento, permitindo, assim, um maior nível de conhecimento quanto ao comportamento dos elementos e suas interações. No nível de detalhamento desejado, utiliza-se a Rede de Petri na modelagem dos elementos básicos do sistema, que são, assim como na orientação a objetos, denominados classes. Em seguida, através de uma abordagem bottom-up, estes modelos são agrupados, formando modelos mais complexos: componentes e aplicativos. A fim de garantir a interação entre estes elementos, foram definidos um conjunto de interfaces, bem como suas regras de relacionamento. Este método foi aplicado a um estudo de caso para comprovar sua eficácia. No que diz respeito ao algoritmo proposto para sincronizar os tempos de simulação, utiliza-se como subsidio o mecanismo de gerenciamento da transmissão de dados em redes conhecido como Token Ring. Um simulador de eventos, distribuído, foi implementado com a finalidade de validar o algoritmo proposto. / Evolution on the information technology, telecommunications and transport systems, associated to social and economic changes around the world have caused a significative reorganization of the industry. In this context, a high level of decentralization and specialization of the productive units, as well as an increment of the automation level used in productive processes have been verified. It results on the increase of the amount and the complexity of the enterprise subsystems interactions. Modeling techniques are used with simulation to deal with the complexity, to analysis, and to design new productive systems. Among the simulation approaches, distributed simulation is distinguished. It deals with the execution of simulation in physically dispersed computers connected through a LAN (Local Area Network), providing, for example, the reduction of the simulation time, huge simulation models (models with many elements), fault tolerance, as well as geographic dispersion. To contribute for the evolution of modeling and simulation techniques, in special the distributed one, it is proposed on this work: (1) a new method for the hierarchical modeling of productive systems; and (2) a new time synchronization algorithm used to manage the time evolution of a set of distributed simulation software. On the proposed modeling method it is used a top-down approach to decompose the system in basic elements, starting in a high-level abstraction model, and ending with a set of basic models with high level of detail. Then, these models are modeled using Petri net. As well as on object-oriented languages, each model is called class. After that, using a bottom-up approach, these basic models are grouped to generate more complex models: component and application. A set of interfaces, as well as its relationship rules had been defined to guarantee the interaction among these elements. This method was applied to a case study to confirm its effectiveness. About the time synchronization algorithm, the token ring protocol is used as subsidy. An event based distributed simulator was implemented with the purpose to validate the proposed algorithm.