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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

Magnetic signature characterization of a fixed-wing vertical take-off and landing (VTOL) unmanned aerial vehicle (UAV)

Hansen, Cody Robert Daniel 17 December 2018 (has links)
The use of magnetometers combined with unmanned aerial vehicles (UAVs) is an emerging market for commercial and military applications. This study presents the methodology used to magnetically characterize a novel fixed-wing vertical take-off and landing (VTOL) UAV. The most challenging aspect of integrating magnetometers on manned or unmanned aircraft is minimizing the amount of magnetic noise generated by the aircraft’s onboard components. As magnetometer technology has improved in recent years magnetometer payloads have decreased in size. As a result, there has been an increase in opportunities to employ small to medium UAV with magnetometer applications. However, in comparison to manned aviation, small UAVs have smaller distance scales between sources of interference and sensors. Therefore, more robust magnetic characterization techniques are required specifically for UAVs. This characterization determined the most suitable position for the magnetometer payload by evaluating the aircraft’s static-field magnetic signature. For each aircraft component, the permanent and induced magnetic dipole moment characteristics were determined experimentally. These dipole characteristics were used to build three dimensional magnetic models of the aircraft. By assembling the dipoles in 3D space, analytical and numerical static-field solutions were obtained using MATLAB computational and COMSOL finite element analysis frameworks. Finally, Tolles and Lawson aeromagnetic compensation coefficients were computed and compared to evaluate the maneuver noise for various payload locations. The magnetic models were used to study the sensitivity of the aircraft configuration and to simultaneously predict the effects at potential sensor locations. The study concluded by predicting that a wingtip location was the area of lowest magnetic interference. / Graduate
202

Myodynamika oporové fáze při odrazových pohybech člověka / Myodynamics of the support phase during different take-off tasks in human locomotion

Hojka, Vladimír January 2013 (has links)
Title: Myodynamics of the support phase during different take-off tasks in human locomotion Objectives: Six types of take-off movement were analyzed in terms of support limb kinematics, take-off dynamics and muscle activation, in order to identify differences in motor control. Methods: 14 male athletes (22.6 ± 4.4 years; 182.4 ± 5.3 cm; 74.7 ± 6.2 kg) took part in laboratory experiment. Each athlete performed six different take-off movements (running, acceleration - first and second step, long jump take-off, high jump take-off and take-off to the hurdle). System Qualisys was used to analyze kinematics of the support limb. Dynamic of the suport phase was measured with Kistler 9281 EA force- plate. ME6000 apparatus was used to measure the muscle activation. Results were processed and statistically evaluated in Matlab (MathWorks, Inc) environment. Pair ANOVA, T-test and Friedmann test were performed to identify differences between take-off movements. regression analysis was introduced to find the relationship between parameters. Results: Significant differences in take-off dynamics are realized with not so significant differences in kinematic and electromyographic parameters. high jump and long jump take-offs acted most specifically in comparison with other types of take-offs. Two typically...
203

Programa Vamos Cuidar do Brasil com Escolas Sustentáveis : análise de uma experiência na Escola Estadual Antonio Padilha no munícipio de Sorocaba-SP

Freitas, Maria Estela Maciel 21 September 2015 (has links)
Submitted by Regina Correa (rehecorrea@gmail.com) on 2016-09-19T14:29:30Z No. of bitstreams: 1 DissMEMF.pdf: 1928126 bytes, checksum: 16d2b42091b2741c7212cb9748f1aac8 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-23T18:19:57Z (GMT) No. of bitstreams: 1 DissMEMF.pdf: 1928126 bytes, checksum: 16d2b42091b2741c7212cb9748f1aac8 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-23T18:20:03Z (GMT) No. of bitstreams: 1 DissMEMF.pdf: 1928126 bytes, checksum: 16d2b42091b2741c7212cb9748f1aac8 (MD5) / Made available in DSpace on 2016-09-23T18:20:10Z (GMT). No. of bitstreams: 1 DissMEMF.pdf: 1928126 bytes, checksum: 16d2b42091b2741c7212cb9748f1aac8 (MD5) Previous issue date: 2015-09-21 / Não recebi financiamento / Considering that the construction of sustainable social practices are central goals to guide the education of citizens in any learning context the Ministry of Education (MEC) has prepared the Progran “Let’s take care of Brazil” with sustainable schools which provides guidelines for the development of environmental education practices in schools. To participate in this program the school must present an ongoing project, addressing social and environmental issues in which the student is the subject of their learning in order to reach a personal, collective, conscious and critical training. Thus, among the objectives of this research are highlighted as follows: describe and analyze the development of the Program proposed by Ministry of Education (MEC) “Let’s take care of Brazil with sustainable schools / COM –VIDA” in school E.E. Antonio Padilha, located in Sorocaba-SP between the years 2013 and 2014, describe and analyze the practices developed by COM-VIDA and identify practices related to sustainability of those involved in the project. The methodology that leads this research is the study of qualitative case, as the case study focuses on a particular event revealing its peculiarities. For data collection were used different methods such as document analysis, participant observation, questionnaires and semi-structured interview. The Project began timidly in 2013 with the realization of practices that motivated students to participate in the IV National Children and Youth Conference for the Environment and as a result, we have the first group of students who started actions of environmental education at school. In 2014, such actions kept leading the construction of the COM-VIDA, a discussion space on environmental issues, providing carrying out actions to improve the quality of life and sustainability in the school environment. The implementation of the program and the construction of the COM-VIDA, provided to students of elementary school (6º to 9º years) practical experiences in environmental education focused on sustainability. The workshops COM-VIDA, guided in education for sustainability, the students had the opportunity to identify, discuss and propose solutions to local environmental and social problems. Among these activities are the awareness Project “Sustainability without being cliché” about the waste and proper disposal of garbage with the implementation of selective collection in our school, and growing food in the school garden. All activities were designed by the students themselves are the main protagonists in this process. Through these experiences for building theory knowledge about sustainability, it has been built their environmental identities. The move COM-VIDA has made the theme enter therein in the school environment both by students and by the managment staff causing small changes in individual and collective attitudes of the entire school community. / Tendo em vista que a construção de práticas sociais sustentáveis são metas centrais para orientar a educação dos cidadãos em qualquer contexto de aprendizagem o Ministério da Educação (MEC) lançou, em 2003, o programa “Vamos cuidar do Brasil com Escolas Sustentáveis/ COM VIDA” que apresenta diretrizes para a elaboração de práticas de Educação Ambiental no contexto escolar. O objetivo central dessa pesquisa foi descrever e analisar o desenvolvimento desse programa na Escola Estadual Antônio Padilha, localizada no município de Sorocaba-SP entre os anos de 2013 e 2014. Especificamente buscou-se descrever e analisar as práticas desenvolvidas pelo “COMVIDA” e identificar práticas relacionadas à sustentabilidade dos envolvidos no projeto da referida escola. Trata-se de uma pesquisa do tipo estudo de caso qualitativo e os procedimentos de tomada de dados referem-se a análise documental, a observação participante, a aplicação de questionários e realização de entrevista semiestruturada. Como procedimento de análise do conteúdo adotou-se a perspectiva da análise textual discursiva. Como principais resultados têm-se no ano de 2013, a realização de práticas que motivaram os estudantes para a participação da IV Conferência Nacional Infanto- Juvenil pelo Meio Ambiente resultando na organização de um grupo de estudantes que iniciaram ações de Educação Ambiental na escola. No ano de 2014 as ações continuaram dando origem a construção da COM-VIDA, um espaço de discussões sobre as questões ambientais que tem por objetivo a realização de ações para a melhoria da qualidade de vida e sustentabilidade do ambiente escolar. A implementação do projeto e a construção da COM-VIDA, proporcionou aos estudantes do Ensino Fundamental (6º ao 9º ano) experiências práticas em Educação Ambiental voltada para a sustentabilidade. Dentre as atividades desenvolvidas destacou-se o projeto de conscientização “sustentabilidade sem ser clichê” sobre o desperdício e o descarte adequado do lixo com a implantação da coleta seletiva na escola e o cultivo de alimentos na horta escolar. Todas as atividades foram elaboradas pelos próprios estudantes sendo os principais protagonistas nesse processo. Essas experiências contribuíram para construção de conhecimentos teóricos e práticos sobre sustentabilidade, ajudando na formação das identidades ambientais dos estudantes e na minha formação como docente. A movimentação da COM-VIDA fez com que o tema adentrasse no ambiente escolar, tanto pelos estudantes quanto pela equipe gestora, professores e funcionários ocasionando pequenas mudanças nas atitudes individuais e coletivas da comunidade escolar.
204

Emprego de redes neurais artificiais supervisionadas e n?o supervisionadas no estudo de par?metros reol?gicos de excipientes farmac?uticos s?lidos

Navarro, Marco Vin?cius Monteiro 05 February 2014 (has links)
Made available in DSpace on 2014-12-17T14:25:22Z (GMT). No. of bitstreams: 1 MarcoVMN_TESE.pdf: 3982733 bytes, checksum: 381ae79721c75a30e3373fe4487512c7 (MD5) Previous issue date: 2014-02-05 / In this paper artificial neural network (ANN) based on supervised and unsupervised algorithms were investigated for use in the study of rheological parameters of solid pharmaceutical excipients, in order to develop computational tools for manufacturing solid dosage forms. Among four supervised neural networks investigated, the best learning performance was achieved by a feedfoward multilayer perceptron whose architectures was composed by eight neurons in the input layer, sixteen neurons in the hidden layer and one neuron in the output layer. Learning and predictive performance relative to repose angle was poor while to Carr index and Hausner ratio (CI and HR, respectively) showed very good fitting capacity and learning, therefore HR and CI were considered suitable descriptors for the next stage of development of supervised ANNs. Clustering capacity was evaluated for five unsupervised strategies. Network based on purely unsupervised competitive strategies, classic "Winner-Take-All", "Frequency-Sensitive Competitive Learning" and "Rival-Penalize Competitive Learning" (WTA, FSCL and RPCL, respectively) were able to perform clustering from database, however this classification was very poor, showing severe classification errors by grouping data with conflicting properties into the same cluster or even the same neuron. On the other hand it could not be established what was the criteria adopted by the neural network for those clustering. Self-Organizing Maps (SOM) and Neural Gas (NG) networks showed better clustering capacity. Both have recognized the two major groupings of data corresponding to lactose (LAC) and cellulose (CEL). However, SOM showed some errors in classify data from minority excipients, magnesium stearate (EMG) , talc (TLC) and attapulgite (ATP). NG network in turn performed a very consistent classification of data and solve the misclassification of SOM, being the most appropriate network for classifying data of the study. The use of NG network in pharmaceutical technology was still unpublished. NG therefore has great potential for use in the development of software for use in automated classification systems of pharmaceutical powders and as a new tool for mining and clustering data in drug development / Neste trabalho foram estudadas redes neurais artificiais (RNAs) baseadas em algoritmos supervisionados e n?o supervisionados para emprego no estudo de par?metros reol?gicos de excipientes farmac?uticos s?lidos, visando desenvolver ferramentas computacionais para o desenvolvimento de formas farmac?uticas s?lidas. Foram estudadas quatro redes neurais artificiais supervisionadas e cinco n?o supervisionadas. Todas as RNAs supervisionadas foram baseadas em arquitetura de rede perceptron multicamada alimentada ? frente (feedfoward MLP). Das cinco RNAs n?o supervisionadas, tr?s foram baseadas em estrat?gias puramente competitivas, "Winner-Take- All" cl?ssica, "Frequency-Sensitive Competitive Learning" e "Rival-Penalize Competitive Learning" (WTA, FSCL e RPCL, respectivamente). As outras duas redes n?o supervisionadas, Self- Organizing Map e Neural Gas (SOM e NG) foram baseadas estrat?gias competitivo-cooperativas. O emprego da rede NG em tecnologia farmac?utica ? ainda in?dito e pretende-se avaliar seu potencial de emprego como nova ferramenta de minera??o e classifica??o de dados no desenvolvimento de medicamentos. Entre os prot?tipos de RNAs supervisionadas o melhor desempenho foi conseguido com uma rede de arquitetura composta por 8 neur?nios de entrada, 16 neur?nios escondidos e 1 neur?nio de sa?da. O aprendizado de rede e a capacidade preditiva em rela??o ao ?ngulo de repouso (α) foi deficiente, e muito boa para o ?ndice de Carr e fator de Hausner (IC, FH). Por esse motivo IC e FH foram considerados bons descritores para uma pr?xima etapa de desenvolvimento das RNAs supervisionadas. As redes, WTA, RPCL e FSCL, foram capazes de estabelecer agrupamentos dentro da massa de dados, por?m apresentaram erros grosseiros de classifica??o caracterizados pelo agrupamento de dados com propriedades conflitantes, e tamb?m n?o foi poss?vel estabelecer qual o crit?rio de classifica??o adotado. Tais resultados demonstraram a inviabilidade pr?tica dessas redes para os sistemas estudados sob nossas condi??es experimentais. As redes SOM e NG mostraram uma capacidade de classifica??o muito superior ?s RNAs puramente competitivas. Ambas as redes reconheceram os dois agrupamentos principais de dados correspondentes ? lactose (LAC) e celulose (CEL). Entretanto a rede som demonstrou defici?ncia na classifica??o de dados relativos aos excipientes minorit?rios, estearato de magn?sio (EMG), talco (TLC) e atapulgita (ATP). A rede NG, por sua vez, estabeleceu uma classifica??o muito consistente dos dados e resolveu o erro de classifica??o apresentados pela rede SOM, mostrando-se a rede mais adequada para a classifica??o dos dado do presente estudo. A rede Neural Gas, portanto, mostrou- se promissora para o desenvolvimento de softwares para uso na classifica??o automatizada de sistemas pulverulentos farmac?uticos
205

Concep??es de inf?ncia e de educa??o infantil que permeiam a pr?tica docente

Pinheiro, Maria Margarida 19 November 2008 (has links)
Made available in DSpace on 2014-12-17T14:36:11Z (GMT). No. of bitstreams: 1 MariaMP.pdf: 633833 bytes, checksum: 5d0e5bdd83d3d13a66b2e3ada0568c73 (MD5) Previous issue date: 2008-11-19 / This investigation proposes to analyze the teaching practice in the Child Education, considering the childhood and the Child Education conceptions declared by the teachers. It was opted as methodological approach the qualitative conception of research, marking a critical perspective of the subjects, and their relations in the educational processes. It was privileged as instruments of construction of the data, the observation of the practices of the teachers developed in the ordinary day, the semistructured interviews, and the documental analysis to complement information, through the developing report of the students, done by the teachers in the end of the teaching year. This way, from the understanding of the childhood in a social perspective, and historically constructed, considering the concrete children insertion in the social reality and the child as a whole subject and by rights, it was developed the interpretative analysis of the data. The investigated reality showed that the childhood conceptions linked to the comprehension of child and child development, declared by the teachers, subjects of the research, have been associated, in some aspects, to the present thought of thinking and acting in relation to the small child, evidencing, consequently, several limitations of pedagogical order, and the demanding evidence of a bigger development of the teachers about the question. / Esta investiga??o prop?e-se a analisar a pr?tica docente na Educa??o Infantil, considerando-se as concep??es de inf?ncia e de educa??o infantil declaradas pelas professoras. Optou-se como abordagem metodol?gica a concep??o de pesquisa do tipo qualitativa, demarcando-se uma postura cr?tica sobre os sujeitos e suas rela??es nos processos educativos. Privilegiou-se como instrumentos de constru??o dos dados, a observa??o das pr?ticas das professoras desenvolvidas no cotidiano, as entrevistas semi-estruturadas e a an?lise documental para complementar informa??es, atrav?s do relat?rio de desenvolvimento dos(a) alunos(a), feitos pelas professoras no final do ano letivo. Nesse sentido, partindo-se do entendimento de inf?ncia numa perspectiva social e historicamente constru?da, considerando-se a inser??o concreta das crian?as na realidade social e vendo a crian?a como sujeito integral e de direitos, desenvolveu-se a an?lise interpretativa dos dados. A realidade investigada apontou que as concep??es de inf?ncia aliadas ? compreens?o sobre crian?a e desenvolvimento infantil, declaradas pelas professoras, sujeitos da pesquisa, t?m se associado, em alguns aspectos, ao pensamento atual de pensar e agir em rela??o ? crian?a pequena, evidenciando-se, por conseguinte, v?rias limita??es de ordem pedag?gica, e a evid?ncia de demandas de um maior aprofundamento das professoras acerca da quest?o
206

Konsten att övertyga : En kvalitativ innehållsanalys av valkampanjerna i samband med den brittiska folkomröstningen under 2016

Karlsson, Patrik January 2018 (has links)
Syftet med följande undersökning var att analysera korrelationerna mellan valkampanjerna Britian Stronger In Europe och Vote Leave, Take Back Control i förhållande till retorikens tre element ethos (trovärdighet), logos (förnuft) och pathos (känslor). Utifrån en kvalitativ innehållsanalys har valkampanjernas dokument, rapporter, affischer, tal och videoklipp analyserats för att presentera korrelationerna faktorerna emellan. Undersökningen kommer fram till att valkampanjen Britian Stronger In Europe och dess kampanjmaterial gick att korrelera till samtliga retoriska element, medan Vote Leave-kampanjen enbart gick att korrelera till ethos- och pathos-elementen. Anledningen till detta berodde på att Vote Leave-kampanjen inte utgick från något tillförlitligt material för att styrka sitt ställningstagande i relation till Storbritanniens medlemskap i EU, vilket var ett krav för att uppfylla logos-elementets kännetecken. Detta till trots, lyckades Vote Leave-kampanjen gå segrande ur den brittiska folkomröstningen med 52 % av rösterna gentemot Stronger In-kampanjens 48 %.
207

Mediando uma cultura da não-violência: a municipalização da medida de liberdade assistida na integração social do adolescente em conflito com a lei

Duque, Sidnéia Bento 21 June 2006 (has links)
Made available in DSpace on 2016-12-23T14:36:53Z (GMT). No. of bitstreams: 1 Sidneia Bento Duque.pdf: 945477 bytes, checksum: 38005a21ae82f83ddd3efc1036a22b94 (MD5) Previous issue date: 2006-06-21 / Estudo de caso exploratório que busca analisar as medidas sócio-educativas de liberdade assistida de atendimento ao adolescente em conflito com a lei desenvolvidas no município de Colatina\ES. O presente estudo teve como objetivo analisar a percepção do adolescente em conflito com a lei da medida sócio-educativa de liberdade assistida, tendo em vista os valores que ele destaca como importantes no processo de integração social. Os valores deveriam ser propiciadores da mediação para a construção de uma cultura da não-violência. Foram realizadas entrevistas semi-estruturadas com 15 (quinze) adolescentes que participaram do programa de Liberdade Assistida da Prefeitura Municipal de Colatina/ES durante o ano de 2005. Foi remetido questionário para a equipe técnica do programa, além de grupo focal com os familiares para corroborar com as informações fornecidas. A abordagem foi quanti-qualitativa e a técnica de análise dos dados utilizada foi à análise de conteúdo. Segundo a percepção dos adolescentes o programa conseguiu destacar os valores de família e cultura. O trabalho, o programa foi considerado relevante em relação às qualificações profissionais, mas deficitário na inserção no mercado de trabalho. A cidadania e a educação como questão política é ainda insuficiente, até porque a redução do Estado conduz as soluções individuais para satisfação das necessidades sociais. O programa de LA aparece como uma tentativa de articular as alianças sociais em torno da problemática que envolve o adolescente em conflito com a lei. A experiência da Prefeitura Municipal de Colatina/ES demonstra ser replicável em outras realidades, pois trabalha com elementos universalizantes sem esquecer as especificidades da realidade local. / Case study explore that analyses the social educational measures of controlled freedom of attainment for the adolescent take in conflict with the law develop in the city of the Colatina/ES. The current study had like goal analyses the perception of adolescent take in conflict with the law about the social educational measures of controlled freedom, aiming to know the important values in the social integration process. The values should be mediation for the no-violence culture. It was realized interviews with fifteen (15) adolescents that participated of the social educational measures of controlled freedom of the Colatina/ES city hall. It was realized questionnaire for the technique group besides focal group with adolescent´s relatives for corroborate with informations furnished. The approach is quanti-quality and the technique datum analyses utilized was the content analyze. According to perception of the adolescents the program got prominence family and culture values. The work, the program was considerated important with regard to professional qualification, but deficient in the insertion in work market. The citizenship and the education like politician issue are still insufficient, because reduction of the State promotes individuals solutions for satisfaction social necessities. The measure of controlled freedom program shows like a tentative of articulate social nets around the problems that involves adolescent take in conflict with the law. The experience of the Colatina/ES city hall could be reproduced in others realities, because uses universal elements without forget the specifics of the local reality.
208

Análise e Desenvolvimento de um Filtro alfa-beta para Medição Indireta de Sistemas Dinâmicos de Primeira Ordem / Analysis and Development of a Filter alpha-beta stop Indirect measurement of Dynamic Systems of First Order

Oliveira, Jaderson Pereira 18 April 2006 (has links)
Made available in DSpace on 2016-08-17T14:52:54Z (GMT). No. of bitstreams: 1 Jaderson Pereira Oliveira.pdf: 404370 bytes, checksum: cdd98c0292ea8584c4aca3a5c5006d3a (MD5) Previous issue date: 2006-04-18 / We present in this work the development of an α-β filter for indirect measurement in 1st order dynamic systems, derived from the known equations for the α-β filter applied to systems with a pure integer. The main α-β filter design parameters analyzed are: the variance reduction factor of the measurement noise and the total transient error for a step input. Further, we present the development of the equations for the calculation of a critically dumped filter. As example of application, we use the concepts developed for the design of an α-β filter for the indirect measurement of the oxygen up-take rate in activated sludge systems in a dissolved oxygen feedback configuration, which can be viewed as a 1st order system. Simulations and comparisons with other methods are carried out in order to illustrate the proposed formulations. / Neste trabalho, apresenta-se o desenvolvimento do filtro α-β para medição indireta em sistemas dinâmicos de 1ª ordem a partir das equações conhecidas do filtro α-β aplicados a sistemas com um integrador puro. Os principais parâmetros de projeto do filtro analisado são: o fator de redução de variância do ruído de medição e o erro total de transitório para uma entrada do tipo degrau. Além disso, apresenta-se o desenvolvimento das equações para o cálculo de um filtro criticamente amortecido. Como exemplo de aplicação, utiliza-se os conceitos desenvolvidos para o projeto de um filtro α-β para medição indireta da taxa de consumo de oxigênio em sistemas de tratamento de esgotos de lodo ativado em uma configuração de realimentação da concentração de oxigênio dissolvido, o qual pode ser considerado um sistema de 1ª ordem. Simulações e comparações com outros métodos são apresentadas de forma a ilustrar a formulação proposta.
209

Gestaltningar av genus i förskolemiljö : En kvalitativ text- och bildanalys av hur genus gestaltas i ett bestämt urval av bilderböcker / Portrayals of gender in preschool environment : A qualitative text- and picture analysis of gender portrayals in picture books

Jessica, Karlsson January 2018 (has links)
The study is a qualitative literature analysis with the purpose of examining how children and preschool pedagogues were portrayed in picture books that take place in the preschool environment, based on gender perspectives. To define the material, books that take place in the preschool environment had been selected. The purpose of the study was also to examine how relationships between children and preschool pedagogues were portrayed, from a gender perspective. And whether there was a difference between the gender portrayals depending on the year when the book was published. The picture book analysis has created an understanding of how preschool pedagogues can work gender pedagogically with literature as a tool, together with the children. The analysis and the results have shown that there are variations in how gender and gender roles were portrayed in the picture books. It also showed that there are picture books that are gender conscious and that some maintain and enhance gender roles.
210

Modelling and Simulation of a Power Take-off in Connection with Multiple Wave Energy Converters

Ghodrati, Ashkan, Rashid, Ahmed January 2014 (has links)
The objective of this thesis is to develop a model that will integrate multiple buoys to a power take-off hub. The model will be derived using a time domain analysis and will consider the hydraulic coupling of the buoys and the power take-off. The derived model is reproduced in MATLAB in order to run simulations. This will give possibility to conduct a parameter study and evaluate the performance of the system. The buoy simulation model is provided by Wave4Power (W4P). It consists of a floater that is rigidly connected to a fully submerged vertical (acceleration) tube open at both ends. The tube contains a piston whose motion relative to the floater-tube system drives a power take-off mechanism. The power take-off model is provided by Ocean Harvesting Technologies AB (OHT). It comprises a mechanical gearbox and a gravity accumulator. The system is utilized to transform the irregular wave energy into a smooth electrical power output. OHT's simulation model needs to be extended with a hydraulic motor at the input shaft. There are control features in both systems, that need to be connected and synchronized with each other. Another major goal within the thesis is to test different online control techniques. A simple control strategy to optimize power capture is called sea-state tuning and it can be achieved by using a mechanical gearbox with several discrete gear ratios or with a variable displacement pump. The gear ratio of the gear box can be regulated according to a 2D look up table based on the average wave amplitude and frequency over a defined time frame. The OHT power take-off utilizes a control strategy, called spill function, to limit the excess power capture and keep the weight accumulator within a span by disengaging the input shaft from the power take-off. This is to be modified to implement power limitation with regulation of the gear ratio of the gearbox. / +46736290781

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