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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.
211

O (re)dimensionamento da temporalidade laboral na vivência de professores tutores da educação on-line / Restructuring temporality labour in the experience of teachers tutors of online education

PONTE, Felipe Teófilo January 2015 (has links)
PONTE, Felipe Teófilo. O (re)dimensionamento da temporalidade laboral na vivência de professores tutores da educação on-line. 2015. 134f. – Dissertação (Mestrado) – Universidade Federal do Ceará, Programa de Pós-graduação em Psicologia, Fortaleza (CE), 2015. / Submitted by Márcia Araújo (marcia_m_bezerra@yahoo.com.br) on 2016-01-20T11:52:46Z No. of bitstreams: 1 2015_dis_ftponte.pdf: 751229 bytes, checksum: e129182d956d9c8e9f8be45aae0acaad (MD5) / Approved for entry into archive by Márcia Araújo(marcia_m_bezerra@yahoo.com.br) on 2016-01-20T12:19:48Z (GMT) No. of bitstreams: 1 2015_dis_ftponte.pdf: 751229 bytes, checksum: e129182d956d9c8e9f8be45aae0acaad (MD5) / Made available in DSpace on 2016-01-20T12:19:48Z (GMT). No. of bitstreams: 1 2015_dis_ftponte.pdf: 751229 bytes, checksum: e129182d956d9c8e9f8be45aae0acaad (MD5) Previous issue date: 2015 / This study was conducted between 2013 and 2015, with the search field the scope of the Distance Learning online and type as the subjects participating Letters Course tutors (Portuguese-English-Spanish) of an institution of public higher education. The objective of this study was to investigate how online education teachers experience resizing the labor temporality. Through qualitative approach, focusing on speeches by professionals in question, spoke about the relationship between the categories of time and effort in order to critically analyze the changes in the working structure and the repercussions that these changes produced in the constitutions subjective workers. By applying semi-structured interviews and methodological resource of hermeneutics social discourse analysis, analyzed how these professionals build and reproduce the temporal system in their work activities. The speeches of the participants highlighted a labor configuration demarcated by a temporal variability and the absence of a time of rigid and inflexible work. In addition, there was a work temporality that is diluted to other social times past, in most cases, to interfere in the daily lives of these professionals. Signs of insecurity emerged in the speeches of tutors such as: accumulation of tasks, fast-paced and intense speed of work, demand for versatility, versatility and flexibility, work devaluation, not professionalization, stretching labor hours. As a result of this study, it was found, then the professor of online education a social agent that explicit in your reality the imperatives of the flexible mechanisms of production. / Este estudo foi realizado entre os anos de 2013 e 2015, tendo como campo de pesquisa o âmbito da Educação a Distância do tipo on-line e como sujeitos participantes os professores tutores do Curso de Letras (Português-Inglês-Espanhol) de uma Instituição de Ensino Superior Pública. O objetivo deste estudo foi investigar como os professores da educação on-line vivenciam o redimensionamento da temporalidade laboral. Por meio da abordagem qualitativa, com enfoque nos discursos dos profissionais em questão, discorreu-se sobre a articulação entre as categorias tempo e trabalho, a fim de analisar criticamente as mudanças na estrutura de trabalho, bem como as repercussões que essas transformações produziram nas constituições subjetivas dos trabalhadores. Mediante a aplicação de entrevista semiestruturada e do recurso metodológico da análise sociohermenêutica do discurso, analisou-se como esses profissionais constroem e reproduzem o sistema temporal em suas atividades laborais. As falas dos participantes ressaltam uma configuração laboral demarcada por uma variabilidade temporal e pela ausência de um tempo de trabalho rígido e inflexível. Além disso, observou-se uma temporalidade de trabalho que se dilui para outros tempos sociais passando, na maioria das vezes, a interferir no cotidiano desses sujeitos. Indícios de precarização e precariedade emergiram nos discursos dos professores tutores, tais como: acumulação de tarefas, ritmo acelerado e intensa velocidade de trabalho, exigência de polivalência, versatilidade e flexibilidade, desqualficação do trabalho, desprofissionalização, alongamento das jornadas laborais. Como fruto deste estudo, encontrou-se, então, no professor da educação on-line um agente social que explicita em sua realidade os imperativos dos mecanismos flexíveis de produção.
212

EXPLORING THE RELATIONSHIP BETWEEN COMMITTED ACTION AND PROCRASTINATION

Legaspi, David Nathaniel 01 May 2017 (has links)
Procrastination has been a concept that has recently gained attention. Current research has provided data that suggests there is a positive relationship between committed action (goal setting) and procrastination (Gagnon, Dionne, & Pychyl, 2016). This study had collected data from self-report only using a procrastination scale that has been globally validated (Steel, 2010). Acceptance and Commitment Therapy (ACT) interacts with a person’s psychological flexibility, which can be described as the ability to contact the present moment and then adapt to changes in that moment (Hayes, Strosahl, & Wilson, 2011). Committed action is just part of the six components that make up ACT. Committed action as a concept is concerned with the goals we take on a daily basis that bring us closer to our values. It stands to reason, that the more a person commits to these actions, the less they might procrastinate. The current study extends the existing literature by exploring the possible effect committed action (goal setting) sessions may have on the relationship between procrastination and committed action by examining discussion question turn in across two groups. The outcomes of this analysis may lend to the literature concerning developing a more effective classroom setting (Bijou, 1970). The current study’s purpose is then to increase the level of understanding we have concerning procrastination through a committed action intervention.
213

The Relationship between Psychological Flexibility, Mindfulness, and Goal-Directed Behaviors Controlled by Executive Function

Ashe, Sarah Cheyanne 01 May 2018 (has links)
The purpose of the present study is to examine the relationship among psychological flexibility, mindfulness, and goal-directed behaviors controlled by executive function, as measured by the Avoidance and Fusion Questionnaire for Youth (AFQ-Y), the Child and Adolescent Mindfulness Measure (CAMM), and the Comprehensive Executive Function Inventory (CEFI). Participants completed the AFQ-Y, CAMM, and CEFI as part of a Midwestern alternative school’s curriculum. Data was collected for 30 participants (male = 28, female = 2) with approval from the school. The results indicate a significant relationship between the AFQ-Y and CAMM (r = -0.7711, p < 0.0001), CAMM and CEFI (r = -0.3226; p = 0.0821), AFQ-Y and the emotion regulation subscale (r = -0.5018; p = 0.0047), as well as the working memory subscale of the CEFI (r = -0.3622; p = 0.0492), and the CAMM and the emotion regulation subscale (r = 0.494; p = 0.0055), organization subscale (r = 0.3723; p = 0.0427), and working memory subscale (r = 0.4725; p = 0.0084). The results are beneficial for clinicians who specialize in providing treatment to children and adolescents with development disabilities and various other disorders. Limitations and future research are also discussed within the current study.
214

Prediction of Clinical Symptoms and Psychological Flexibility Using a Novel Values Card Sort Activity

Kimball, Ryan S. 01 August 2018 (has links)
Values are directly relevant in a number of theoretical orientations in psychology, including Acceptance and Commitment Therapy (ACT). In ACT, clarification of one’s personal values is paramount. The present study examined the ability to predict clinical symptoms and psychological flexibility using variables derived from one’s performance on the ACT Values Card Sort (ACT-VCS), a novel values clarification exercise. The independent variables, obtained from the ACT-VCS, included 1) the number of values endorsed as very important in the initial sort (i.e., valuing propensity), 2) the number of values domains represented in the final sort (i.e., values diversity), and 3) the extent to which one’s values were oriented toward uncontrollable experiences (i.e., control agenda endorsement). Three hierarchical regressions were conducted to examine the extent to which these three predictors accounted for the variance in scores of a) depression, anxiety, and stress, b) psychological flexibility, and c) psychological inflexibility. The psychological flexibility model was significant (∆R squared = .25 (F (3, 69) = 12.20, p < .001) with valuing propensity (squared semi-partial correlation r = .13, p < .001) and control agenda endorsement (squared semi-partial correlation r = .05, p < .01), but not values diversity, independently accounting for a significant portion of the variance. Prior therapy experience moderated some of these relationships. These findings provide preliminary evidence for using performance variables from the ACT-VCS to predict clinical variables.
215

Estudo da utilização da técnica ultrassônica de TOFD com vistas no monitoramento de trincas de fadiga em tubos de aço superdúplex

Lopes, Marcelo de Freitas January 2017 (has links)
Este trabalho buscou avaliar a técnica ultrassônica de Tempo de Voo da Onda Difratada (TOFD - Time-Of-Flight-Diffraction) para o monitoramento de trincas de fadiga nucleadas no interior de tubos de aço Superdúplex. Para isso, foram fabricados corpos de prova do tipo single edge bending SE(B) a partir de um tubo de aço Superdúplex sem costura. Estas amostras foram ensaiadas em fadiga, e o crescimento de trinca foi monitorado com as técnicas de TOFD, de Flexibilidade no Descarregamento (Compliance) – durante os ensaios, foram dadas sobrecargas mecânicas que causaram deformação plástica. As deformações serviram de pontos de referência para analisar o crescimento de trinca. Para aferir a validade os resultados obtidos com o TOFD nos ensaios de fadiga e fazer uma correlação com o monitoramento em campo de defeitos em tubos de aço Superdúplex, foi fabricado um padrão que simulou um tubo com defeito interno conhecido. Este padrão foi inspecionado com o TOFD, empregando os mesmos equipamentos e parâmetros utilizados nos ensaios de fadiga. Foi possível monitorar o crescimento de trinca em fadiga utilizando a técnica de TOFD e houve forte correlação entre os dados obtidos com o TOFD e o Compliance. A inspeção no tubo padrão manteve uma diferença entre a medida real e a obtida com o TOFD proporcional às encontradas durante o monitoramento dos ensaios de fadiga. / This study aimed to evaluate the ultrasonic technique Time-Of-Flight-Diffraction (TOFD) in monitoring fatigue nucleated cracks within super duplex steel pipes. In order to do it, single edge bending SE (B) specimens were manufactured using a super duplex steel seamless pipe. These samples were tested in fatigue and crack growth was monitored with two different techniques: TOFD and Flexibility in Unloading (Compliance). During the tests, it was used mechanical overloadings so deformation would be cause on the steel pipes. The deformations caused by that served as reference points to analyze the cracking growth. Thus, to assess the validity of the data obtained with the TOFD in fatigue tests, it was made a pattern that simulated a tube with known internal defect. This pattern was inspected with the TOFD, using the same equipment and parameters used in the fatigue tests. A correlation with the monitoring of defects field super duplex steel pipes was also made. The experiment has shown it is possible to monitor the cracking growth fatigue using the TOFD technique. Figures indicate, as well, there is a strong correlation between results obtained with the TOFD and Compliance. The inspection of the standard steel pipe maintained a difference between the actual measurement and obtained measurement. That difference was proportional from TOFD data and those found during the monitoring of the fatigue tests.
216

A study of flexible supercapacitors : design, manufacture and testing

Zhang, Ruirong January 2016 (has links)
Supercapacitors have attracted great attention because of their high power density, long life cycle and high efficiency. They can be generally classified into two types: electrical double-layer capacitors (EDLCs) and pseudocapacitors. Compared with pseudocapacitors, EDLCs have a very fast charge/discharge rate, higher power density, higher coulombic efficiency and longer cycle life. Recently, in order to meet the requirements of portable and wearable electronics, supercapacitor development is moving towards flexible and stretchable solutions. This thesis presents the design, fabrication, performance testing and optimisation of flexible strip and fibre EDLCs. In this research, a sandwich structured strip EDLC was designed and manufactured. Experimental design was utilised to optimise the operation parameters of the EDLC in order to improve its capacity for energy storage. The flexibility of the strip EDLCs was studied extensively by mechanical tests under static and dynamic loading conditions, and the correlation between the electrochemical performance of the EDLCs and the mechanical testing process was investigated. Novel coaxial fibre EDLCs have also been studied and developed in this study. Fibre supercapacitors showed a good flexibility and weavability. The activated carbon produced by ball-milling method with optimum specific capacitance was mixed with commercial ink to produce active material to optimise the electrochemical performance of fibre EDLCs. The flexible EDLCs were applied into different appliances to demonstrate the stability of performance and the usability of EDLCs developed in this study. The electrical current and potential range can be altered by connecting multiple strip or fibre EDLCs in parallel or in series to meet the power and energy requirements. It has been proved that the flexible EDLCs developed have a great potential to be used as energy storage devices for smart electronics. This thesis makes original contributions to knowledge, including using an advanced test method to study the electrochemical performance of flexible supercapacitors under static and dynamic mechanical testing, investigation of the effect of key parameters in the manufacturing process on the performance of strip supercapacitors using experimental design method to optimise the supercapacitors’ performance, and optimisation of the performance of fibre supercapacitors by improving the structure and using a new active material with higher specific capacitance.
217

Sistemática para avaliação e melhoria da flexibilidade de layout em ambientes dinâmicos / A method to measure and improve layout flexibility in dynamic environments

Neumann, Carla Simone Ruppenthal January 2009 (has links)
Tradicionalmente, para que um layout possa ser avaliado, devem-se enfocar fatores de proximidade e de adjacência, já que os mesmos aumentam a eficiência da movimentação de materiais, o que reduz custos operacionais. Adicionalmente, se sugere acrescentar robustez, flexibilidade, suficiência e utilização do espaço a esses fatores. Nesta tese se apresenta uma sistemática de avaliação e melhoria da flexibilidade de layout em ambientes dinâmicos. Mais explicitamente, propõe-se mensurar os habilitadores de flexibilidade de um layout, ou seja, que o torna capaz de reagir às incertezas externas e internas que surgem à medida que mudam as necessidades futuras da produção. A sistemática proposta é desenvolvida em dez etapas, as quais partem de matrizes semelhantes as do Quality Function Deployment (QFD) para verificar o impacto de fatores de proximidade de departamentos, de utilização de área e de associação com outros tipos de flexibilidade de manufatura na flexibilidade de layout. A tese também traz uma proposta de análise reversa do QFD para comparar o que está realmente sendo valorado pela instalação ao ponderar os indicadores medidos. As proposições apresentadas são ilustradas em um caso prático de uma empresa do setor metal mecânico, representado pela sistemática, pelos índices de flexibilidade de layout e pelos direcionamentos de melhoria. / In the traditional evaluation of layouts emphasis is placed on factors such as proximity and adjacency, as they increase materials handling efficiency, reducing operational costs. It is usually recommended to consider additional factors in the analysis, such as robustness, flexibility, sufficiency and use of space. In this dissertation we propose a method to evaluate and improve layout flexibility in dynamic environments. More explicitly, we propose measuring the enablers of a layout that are capable of reacting to external and internal uncertainties that arise as production needs change. The proposed method is implemented in ten stages. We start using matrices similar to those in the Quality Function Deployment (QFD) method to measure the impact of proximity between departments, use of production space, and association with other types of manufacturing flexibility on layout flexibility. The thesis also presents a proposition where the traditional QFD analysis is performed in reverse. The propositions presented are illustrated in a case study from the metal component processing sector.
218

Habitação social evolutiva : análise do custo inicial de construção de um projeto do tipo embrião

Peña, Arlene Ramírez 09 December 2014 (has links)
Submitted by Simone Souza (simonecgsouza@hotmail.com) on 2017-10-06T13:08:21Z No. of bitstreams: 1 DISS_2014_Arlene Ramirez Pena.pdf: 9065918 bytes, checksum: 7106bef200928cec7a55efd430b56368 (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2017-11-06T11:46:06Z (GMT) No. of bitstreams: 1 DISS_2014_Arlene Ramirez Pena.pdf: 9065918 bytes, checksum: 7106bef200928cec7a55efd430b56368 (MD5) / Made available in DSpace on 2017-11-06T11:46:06Z (GMT). No. of bitstreams: 1 DISS_2014_Arlene Ramirez Pena.pdf: 9065918 bytes, checksum: 7106bef200928cec7a55efd430b56368 (MD5) Previous issue date: 2014-12-09 / CAPES / O problema do déficit habitacional é vivenciado na maioria dos países do mundo. Muitos governos e profissionais tem tentado diminuir este déficit com a criação de distintos programas e projetos de habitação de interesse social. O que acontece com a maior parte destas habitações é que construtivamente são muito rígidas e construídas em serie, pensadas para uma única configuração familiar tradicional, não se adaptando assim às diversas e mutáveis necessidades dos usuários na atualidade. No momento que o morador for realizar modificações, estas tornam se mais custosas e com menor qualidade do que poderiam ser se a moradia fosse planejada inicialmente para evoluir. Embora as vantagens das habitações evolutivas sejam aparentemente maiores do que as desvantagens, a construção das mesmas ainda não é uma prática comum. A ideia de projetar de forma “inacabada” em termos de espaços e de acabamentos, deixando que o usuário seja o seu próprio arquiteto, não é uma prática utilizada por empreendedores e promotores dos conjuntos habitacionais de interesse social. O propósito do presente trabalho é avaliar os custos das habitações do tipo embrião em comparação com as habitações padrão tradicionais não evolutivas. Mediante elaboração de orçamentos, em diferentes cenários, espera-se encontrar alternativas de moradias flexíveis que possam ser viáveis economicamente. A intenção é também despertar o interesse na temática das habitações evolutivas e flexíveis e motivar a criação de novas propostas que de melhor qualidade que proporcionem maior conforto aos usuários das habitações. Os resultados mostraram que os empreendimentos evolutivos, em sua maioria, são projetados para serem ampliados para as laterais e os fundos. O projeto proposto demostrou ser uma boa opção quanto à flexibilidade e diversidade de opções de ampliação. Quanto à parte financeira, possui uma diminuição do custo inicial em comparação com o projeto referência que pode permitir o acesso à habitação a pessoas de mais escassos recursos, como também estes fundos podem ser redirecionados para a compra de terrenos melhores localizados. / The problem of housing shortage is experienced in most countries of the world. Many governments and professionals have been trying to reduce this deficit by creating different programs and projects of social housing. The majority of these houses are designed to be built in series and in a rigid way. These are intended for a traditional family house setting. Therefore, house constructions are not adapted to the changing need of users nowadays. During the occupation phase the dweller usually make changes, personalize or expand his house, but these interventions become more expensive and with less quality than they could be if the house was originally planned to grow. Although the advantages of evolutionary housing are apparently greater than its disadvantages, the construction industry hasn’t adopted this concept as a common practice. The concept of an "unfinished" design, in terms of spaces and finishes, that allows the dweller to be his own architect, is not a practice used by entrepreneurs or housing projects developers. The purpose of this study is to evaluate the costs of embryo type dwellings compared with standard non-progressive traditional dwellings. Through budgeting, in different scenarios, is expected to find economically feasible flexible housing alternatives. The intention is to generate interest in the subject of evolutionary and flexible housing and inspire the creation of new proposals with superior quality and with greater comfort for its users. The results showed that the evolutionary developments mostly are designed to be extended to the sides and to the back of the ground. The proposed project has shown to be a good option for flexibility and diversity of expansion options. As for the financial part, the embryo house has a decreased initial cost compared to the reference design. In this way it can allow access to housing to people of scarce resources, and these initial savings can be redirected to buy a better located land to the residential.
219

Percepções de desigualdade no trabalho a partir de uma perspectiva de gênero: relatos das trabalhadoras de uma grande transnacional do varejo

Almeida, Bruna Lyra Alves de 30 November 2012 (has links)
Made available in DSpace on 2015-04-16T14:49:02Z (GMT). No. of bitstreams: 1 Arquivototal.pdf: 1035045 bytes, checksum: 2b16967e4412d81c42bc23259661fdf6 (MD5) Previous issue date: 2012-11-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The present study aims to examine women's perceptions about their working conditions in a large chain of transnational supermarkets installed in Brazil during trade liberalization in the 1990s. For this goal to be achieved it was necessary the theoretical background about the sexual division of labor, present throughout the history of women's work, and the understanding of the changes which occured in the world of work that developed the phenomenon of precariousness and labor flexibility. The retail supermarket segment suffered the impacts of the flexibility and precariousness unleashed in the labor world, that reflected in the introduction of technological innovations and the policy of reducing operating costs. These changes impacted the worker, as, the studied firms have adopted a management philosophy based on the toyotist model, as horizontalization, downsizing, Just in time, polyvalence and teamwork. The adoption of new processes and ways of managing gave the companies more scope to explore the workforce, increase the working hours and manipulate the worker to their interests. The women s situation, in this context, was the focus of this research, once their womanhood is associated to different aspects of discrimination and inequalities both in production and in the reproductive sphere. They always faced more challenges than men to consolidate in the labor market and are the most concentraded on precarious occupations. This study was delineated by a qualitative research whose case study was conducted in a multinational grocery business, known for adopting tough policies against competition, which operates in 18 states of Brazil. Fifteen women who worked or work at stores of the analyzed company, located in the great João Pessoa were interviewed. It was proved that, through the interviews made that perceptions of unequal gender perspective are contradictory in the sense that the talks induce the manipulated speech of the company, however, experiments show a strong impact scenario of working flexibility policies and extreme exploration of the worker, a fact that is more threatening for women, who face the double day wear and prejudice and discrimination in their professional context. / O presente estudo teve como objetivo geral analisar as percepções das mulheres acerca das suas condições de trabalho em uma grande cadeia transnacional de supermercados instalada no Brasil no período de abertura comercial dos anos 1990. Para que este objetivo fosse atingido fez-se necessário o embasamento teórico a respeito da divisão sexual do trabalho, presente em toda a história do trabalho feminino e o entendimento das transformações ocorridas no universo do trabalho que desenvolveram o fenômeno da precarização e flexibilização do trabalho. O segmento de varejo supermercadista sofreu os impactos da flexibilização e precarização desencadeadas no mundo do trabalho, que se refletiram na introdução das inovações tecnológicas e na política de redução de custos operacionais. Essas transformações impactaram o trabalhador, à medida que as empresas do segmento estudado adotaram a filosofia de gestão baseada no modelo toyotista, como horizontalização, enxugamento, Just in time, polivalência e trabalho em equipe. A adoção de novos processos e formas de gestão concedeu às empresas mais margem para explorar a mão-de-obra, intensificar a jornada de trabalho e manipular ideologicamente o trabalhador em função dos seus interesses. A situação das mulheres, nesse contexto, foi o foco da presente pesquisa, uma vez que sua condição de mulher está associada a diversos aspectos de discriminação e desigualdades tanto na esfera produtiva quanto na reprodutiva. Elas sempre enfrentaram mais desafios do que os homens para se consolidar no mercado de trabalho e estão majoritariamente concentradas em ocupações precarizadas. O presente estudo se delineou por meio de uma pesquisa qualitativa, cujo estudo de caso foi realizado em uma multinacional do ramo de supermercados que atua em 18 estados do Brasil, conhecida mundialmente por adotar políticas acirradas de competição. Foram realizadas 15 entrevistas com mulheres que trabalharam ou trabalham em lojas da empresa analisada, localizadas na cidade de João Pessoa/Paraíba. Constatou-se, portanto, através das entrevistas realizadas, que as percepções acerca das desigualdades de gênero são contraditórias, no sentido de que as falas aduzem ao discurso manipulatório da empresa. Contudo, as experiências retratam um cenário de forte impacto das políticas de flexibilização do trabalho e de extrema exploração do trabalhador, fato que se mostra mais ameaçador para as mulheres, que enfrentam o desgaste da dupla jornada e os preconceitos e discriminações no seu contexto profissional.
220

Estudo da utilização da técnica ultrassônica de TOFD com vistas no monitoramento de trincas de fadiga em tubos de aço superdúplex

Lopes, Marcelo de Freitas January 2017 (has links)
Este trabalho buscou avaliar a técnica ultrassônica de Tempo de Voo da Onda Difratada (TOFD - Time-Of-Flight-Diffraction) para o monitoramento de trincas de fadiga nucleadas no interior de tubos de aço Superdúplex. Para isso, foram fabricados corpos de prova do tipo single edge bending SE(B) a partir de um tubo de aço Superdúplex sem costura. Estas amostras foram ensaiadas em fadiga, e o crescimento de trinca foi monitorado com as técnicas de TOFD, de Flexibilidade no Descarregamento (Compliance) – durante os ensaios, foram dadas sobrecargas mecânicas que causaram deformação plástica. As deformações serviram de pontos de referência para analisar o crescimento de trinca. Para aferir a validade os resultados obtidos com o TOFD nos ensaios de fadiga e fazer uma correlação com o monitoramento em campo de defeitos em tubos de aço Superdúplex, foi fabricado um padrão que simulou um tubo com defeito interno conhecido. Este padrão foi inspecionado com o TOFD, empregando os mesmos equipamentos e parâmetros utilizados nos ensaios de fadiga. Foi possível monitorar o crescimento de trinca em fadiga utilizando a técnica de TOFD e houve forte correlação entre os dados obtidos com o TOFD e o Compliance. A inspeção no tubo padrão manteve uma diferença entre a medida real e a obtida com o TOFD proporcional às encontradas durante o monitoramento dos ensaios de fadiga. / This study aimed to evaluate the ultrasonic technique Time-Of-Flight-Diffraction (TOFD) in monitoring fatigue nucleated cracks within super duplex steel pipes. In order to do it, single edge bending SE (B) specimens were manufactured using a super duplex steel seamless pipe. These samples were tested in fatigue and crack growth was monitored with two different techniques: TOFD and Flexibility in Unloading (Compliance). During the tests, it was used mechanical overloadings so deformation would be cause on the steel pipes. The deformations caused by that served as reference points to analyze the cracking growth. Thus, to assess the validity of the data obtained with the TOFD in fatigue tests, it was made a pattern that simulated a tube with known internal defect. This pattern was inspected with the TOFD, using the same equipment and parameters used in the fatigue tests. A correlation with the monitoring of defects field super duplex steel pipes was also made. The experiment has shown it is possible to monitor the cracking growth fatigue using the TOFD technique. Figures indicate, as well, there is a strong correlation between results obtained with the TOFD and Compliance. The inspection of the standard steel pipe maintained a difference between the actual measurement and obtained measurement. That difference was proportional from TOFD data and those found during the monitoring of the fatigue tests.

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