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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.
131

Failure analysis of bonded steel/CFRP laminate connections

Yahya, Najeeb Ali January 2015 (has links)
Adhesive-bonded applications are widely used in industry, because of significant advantages such as uniform stress distribution, design flexibility and suitability to bond similar and dissimilar structural materials. This study focuses the adhesive-bonded long overlap of steel/carbon fibre reinforced polymer (CFRP) composite double lap shear (DLS) joints. The purpose of the work is to predict and assess the structural failure and behaviour of the DLS joint, including delamination of the composite, and to determine the effects of the design parameters of adherend thickness, overlap length and fabric orientation on the joint’s failure. There are different ways for such a joint to fail, which makes predicting failure very difficult. Another important difference is the failure mode of composites, where the relatively low interlaminar shear or tensile strength of the resin system causes failure of the composite before failure of the adhesive bondline occurs. Both experimental and numerical methods were used for the analysis. The experimental programme includes fabrication, mechanical testing and failure examinations of various joints. The numerical methods are based on 2D models, using strength of materials and cohesive zone modelling (CZM) approaches. In order to model adhesive joints accurately and efficiently, fracture tests were implemented to determine the fracture criteria. Mode-I and mode-II fracture energies were obtained by double cantilever beam (DCB) and end notched flexure (ENF) tests. An inverse method was used to define the cohesive parameters of the bilinear relation, fitting the numerical and experimental load-displacement curves. The DLS model has been created in Abaqus software, and results for each approach have been presented. Critical locations of stress concentrations in the DLS joint were identified, and the CZM successfully predicted the delamination initiation and propagation region observed in the experiment. As a result, it was concluded that the data obtained from the analysis showed good agreement with the experimental results, and in addition to the fibre orientation angles of the CFRP laminate markedly affecting the failure load of joints, the failure mode and stress distributions appeared in adhesive and composite. Furthermore, the study shows that the cohesive elements enable the numerical results to be obtained in shorter simulation times than the strength of materials approach, which should encourage use of CZM to analyse large structural applications.
132

N. Hingley & Sons Limited - Black Country Anchor Smith and Chain Cable Maker : a study of the world's premier manufacturer of ships' anchors and cables in the period 1890-1918

Mallin, Kenneth January 1996 (has links)
The principal objective of this dissertation is to position the firm of N Hingley & Sons Limited in its rightful place in the economic history of the Black Country and of Britain in the period 1890 to 1918. As an original contribution to knowledge of the subject, the study focuses on a modestly sized firm of ironmakers in the Black Country that achieved a position of almost total hegemony in the provision of anchors and ships cables to the navies and merchant fleets of the world. This was at a time when 90 per cent of all chain manufactured in Britain came from the Black Country and when the bulk of the ships of the world were constructed in British yards. The success of the firm was based on the solid foundation built by Noah Hingley in harnessing natural resources to a cooperative labour force under the direction of a paternalistic family of marked goodwill. Chapters two and three place the Hingley firm in the economic context of the times. Particular attention is given to how well the enterprise conforms to NrCloskey's analysis that in this period British industry did well and did all that could have been reasonably expected of it. Chapter four draws heavily on the Hingley archival material to establish an outline of the firm's trading activities during the period under review. This process is extended to the limits of the files in chapters five, six and seven. Chapter five examines the evolution from a family partnership to a closely held family company to a broadly held private company demonstrating the continuing ability of the Hingley family to adapt, developing an appropriate structure at each stage. Chapter six examines the basis of Hingleys' hegemonic position : the excellence of its wrought iron, its ability to fashion large diameter cable (up to 6"), and its state-of-the-art anchors. Chapter seven examines the form and development of Hingleys' highly efficient method of marketing. This was a method that ensured that the entirety of its production was always sold year on year and regardless of the fluctuations of business activity. Chapter eight is supplementary to chapter seven and examines Hingleys' greatest achievement. This was the firm's ability to create combinations of manufacturers and mini-cartels in order to capture the lion's share of the production of large diameter ships' cables and anchors for a selected list of firms. This was not a simple rigging of the market. Rather, it was a precondition of sustained high quality that provided a first class product at a fair price. The navies of the world benefited from this strategy. The provision of first class products allied to excellent marketing was the key to Hingleys status in the industry. Chapter nine, dealing with relations with governments, examines the growing levels of state control in the period under review. Beginning with the unstoppable momentum for social and political change, the emergence of the military-industrial complex world wide ensured a greater degree of involvement by the state in matters of business and commerce. In the latter stages of the chapter, the way in which the Board coped with the command economy of the Great War is examined in the context of the resilience of the firm in adapting to the economic and cultural changes of the first quarter of the current century. It was this ability that enabled it to trade on successfully for a further fifty years after the end of this story. My dissertation endeavours to show that Noah Hingley's firm was a fine example of solid achievement within the parameters of what was sensible and economically achievable in Britain at that time.
133

Diagnostic and prognostic analysis tools for monitoring degradation in aged structures

Rosunally, Yasmine Zaina January 2012 (has links)
This research addresses the problem of prolonging the life of aged structures of historical value that have already outlived their original designed lives many times. While a lot of research has been carried out in the field of structural monitoring, diagnostics and prognostics for high tech industries, this is not the case for historical aged structures. Currently most maintenance projects for aged structures have focused on the instrumentation and diagnostic techniques required to detect any damage with a certain degree of success. This research project involved the development of diagnostic and prognostic tools to be used for monitoring and predicting the ‘health’ of aged structures. The diagnostic and prognostic tools have been developed for the monitoring of Cutty Sark iron structures as a first application. The concept of canary and parrot sensor devices are developed where canary devices are small, accelerated devices, which will fail according to similar failure mechanisms occurring in an aged structures and parrot devices are designed to fail at the same rate as the structure, thus mimicking the structure. The model-driven prognostic tool uses a Physics-of-Failure (PoF) model to predict remaining life of a structure. It uses a corrosion model based on the decrease in corrosion rate over time to predict remaining life of an aged iron structures. The data-driven diagnostic tool developed uses Mahalanobis Distance analysis to detect anomalies in the behaviour of a structure. Bayesian Network models are then used as a fusion method, integrating remaining life predictions from the model-driven prognostic tool with information of possible anomalies from data-driven diagnostic tool to provide a probability distribution of predicted remaining life. The diagnostics and prognostic tools are validated and tested through demonstration example and experimental tests. This research primarily looks at applying diagnostic and prognostic technologies used in high-tech industries to aged iron structures. In order to achieve this, the model-driven and data-driven techniques commonly used had to be adapted taking into consideration the particular constraints of monitoring and maintaining aged structures. The fusion technique developed is a novel approach for prognostics for aged structures and provides the flexibility often needed for diagnostic and prognostic tools.
134

Avaliação do aprendizado na produtividade de um estaleiro: uma abordagem através da dinâmica de sistemas. / Shipyard learning effects in productivity: a system dynamics approach.

Baitello, André 28 May 2012 (has links)
Profundas transformações na política energética brasileira têm motivado a revitalização da indústria naval no Brasil. Novos estaleiros estão surgindo em diferentes regiões do país e todos, sem exceção, terão o desafio de aprender com a experiência e, paulatinamente, formar sua força de trabalho. Neste início, que além de árduo é decisivo para o futuro dos estaleiros, é fundamental que se comece a partir das diretrizes corretas, respeitando as mesmas regras básicas que selecionaram os estaleiros que hoje se encontram em posição de destaque no mundo. Os estaleiros japoneses, por exemplo, ergueram as suas bases em um ambiente econômico pós-guerra extremamente restritivo e cheio de dificuldades, mas que os obrigou a desenvolverem um novo paradigma industrial que eliminou desperdícios e possibilitou um salto no desenvolvimento tecnológico e na produtividade na construção naval. Desde então, especialmente após as duas crises do petróleo, a busca pela produtividade em um estaleiro, não é apenas uma questão de competitividade e diferenciação perante os concorrentes, mas um fator de sobrevivência, uma vez que a indústria de construção naval é global e extremamente competitiva em preço, prazo, qualidade, tecnologia e produtividade. Normalmente a produtividade na construção naval é expressa na forma inversa da produtividade parcial da mão de obra (HH/CGT), não por acaso, pois, além da influência de melhores práticas produtivas, sabe-se que o desempenho da força de trabalho representa importante parcela na produtividade de um estaleiro. Neste sentido, esta pesquisa propõe-se a desenvolver um modelo simplificado através da Dinâmica de Sistemas que possibilite simular o comportamento dinâmico da produção, da força de trabalho e da produtividade em um estaleiro para avaliar, através da experiência de modelagem e dos resultados das simulações, cenários que permitam mostrar direções que favoreçam seu aprendizado em produtividade e garantam sua sustentabilidade em função de seu desempenho no longo prazo. A razão desta proposta é explorar algumas das causas que determinam o comportamento dinâmico das curvas de aprendizado dos estaleiros, para então traçar algumas diretrizes que indiquem o caminho para o aprendizado sistêmico. A partir de uma seleção das alavancas para a aprendizagem em produtividade, foram selecionadas cinco diretrizes para estaleiros que tenham o objetivo da aprendizagem, todas relacionadas de alguma maneira com algum aspecto da força de trabalho que são: respeitar os limites do crescimento da força de trabalho, reter experiência e aumentar o seu aproveitamento, criar condições para alavancar o aprendizado da força de trabalho, facilitar a transferência do aprendizado da força de trabalho para o aprendizado da produção e que o aprendizado através de rotinas e processos de produção seja realizado em conjunto com o aprendizado das pessoas. A principal contribuição deste trabalho é a demonstração, através do processo de modelagem e dos resultados da simulação, de um conceito amplamente divulgado pelas teorias de aprendizagem organizacional, de que a origem do aprendizado está nas pessoas e, portanto, são estas os elementos mais importantes do estaleiro. O modelo também ajuda a replicar o paradoxo de que o estaleiro não depende de uma pessoa em específico, mas depende completamente do conjunto formado por todas as pessoas que lá trabalham. Portanto, conforme o pensamento sistêmico define as organizações de aprendizagem, o estaleiro deve ser pensado como um sistema de aprendizagem, em que o desenvolvimento das pessoas é realizado em todos os níveis e o aprendizado ocorre junto com o processo produtivo. / Profound changes in Brazil\'s energy policy have motivated the revitalization of the shipbuilding industry in Brazil. New shipyards are springing up in different regions of the country and all, without exception, have the challenge of learning from experience and gradually train their workforce. At this moment, that is decisive for the shipyards future, it is essential to start from the correct guidelines, respecting the same basic rules that selected established yards which are now in a prominent position in the world shipbuilding market. The Japanese shipyards, for instance, raised its bases in a post-war economic environment extremely restrictive and full of difficulties, but they were compelled to develop a new industrial paradigm that eliminated waste and enabled a leap in technological development and productivity in the shipbuilding process. Since then, especially after the two oil crises, the race for productivity in world yards, is not just a matter of competitiveness and differentiation against competitors, but a survival factor in the shipbuilding industry, now a global industry and extremely competitive in price, time, quality, technology and performance. In the shipbuilding industry, productivity is usually expressed as the inverse ratio of partial labor productivity (or MH/CGT), not only by the influence of best production practices, but also by workforce performance that plays an important share in a shipyard productivity indexes. Therefore, this research proposes to develop a simplified model using System Dynamics practices that allows to simulate the dynamic behavior of production, labor and productivity in a shipyard to assess, through the experience of modeling and simulating, a set of scenarios and show directions to promote learning in productivity and ensure shipyard sustainability in terms of its performance in the long run. The reason for this proposal is to explore some of the causes that determine the dynamic behavior shipyard learning curves, and then draw some guidelines that indicate the path to the systemic learning. From a selection of leverage points for learning productivity, we selected five guidelines for shipyards that have the learning goal, all related in some way with some aspect of the workforce which are: respect the limits of growth of the labor force, retain and increase workforce experience used by learning process, create conditions to empower the learning of the workforce, facilitate the transfer of learning from the workforce to the production learning through frameworks, routines and ensure that production learning is conducted in the same time of individuals learning once they have make concepts and implement new production process. The main contribution of this study is to demonstrate, through the process of modeling and simulation results, a concept widely publicized by the theories of learning organizations, that the source of learning is in people and, therefore, they are the most important elements in the shipyard. The model also helps to replicate the paradox that the shipyard does not depend on any specific person, but depends completely on all shipyard people. Therefore, as defined by systems thinking theories about learning organizations, the shipyard should be thought of as a learning system, where people at all levels are developed and learning occurs in the same time as the production process.
135

O soerguimento da construção naval brasileira nos anos 2000: uma análise neo-schumpeteriana / The soerguimento of the Brazilian naval construction in years 2000: a neo-schumpeteriana analysis

Lima, Guilherme Penin Santos de 30 November 2009 (has links)
A indústria brasileira de construção naval apresentou, ao longo da presente década, crescimento considerável em seu nível de atividade. Tal fato estilizado guarda relação íntima com a dinâmica da indústria de exploração de petróleo em alto mar, mas está relativamente apartado das variáveis que determinam o nível de atividade da indústria em outras regiões do planeta. Tal soerguimento deu-se sobre os escombros de uma profunda crise na qual a indústria esteve imersa por mais de uma década, período durante o qual o paradigma mundial de construção naval transformou-se sobremaneira. Não obstante, alguns dos estaleiros brasileiros lograram atender à demanda relacionada à atividade petrolífera e suprir o mercado com número considerável de embarcações, em curto período de tempo. A partir de marco teórico neo-schumpeteriano, tenta-se, primeiramente, explicar a atual distinção entre os padrões setoriais nacional e dos países líderes da construção naval, em termos da dinâmica tecnológica e de inovação. Uma vez caracterizada tal distinção, analisam-se, para uma amostra de estaleiros nacionais que participaram do esforço de soerguimento da indústria, as estratégias tecnológicas adotadas por cada uma das firmas para capacitar-se ao atendimento do impulso de demanda por embarcações, esforço analítico inspirado em Freeman (1975) e Vermulm (1994). Conclui-se que, enquanto a construção naval dos países líderes de mercado é uma indústria típica dos setores intensivos em escala, a indústria nacional aproxima-se da categoria dos dominados por fornecedores. No que se refere ao âmbito das firmas individuais, vê-se a emergência de heterogeneidade de estratégias, dependentes das trajetórias pregressas dos estaleiros e de suas decisões estratégicas durante a retomada. Tenta-se, por fim, classificálas através de taxonomia elaborada para este fim. / Brazilian shipbuilding industry has experienced considerable growth during the current decade. This fact is closely attached to the dynamics of offshore oil extraction, but is not related to the variables which determine the level of activity of the industry elsewhere. The uplift emerged from the debris of a crisis in which the industry had been deeply immersed for more than a decade. During the crisis, the international shipbuilding paradigm shifted. Nevertheless, some of the Brazilian shipyards succeeded to produce several ships, in a short period of time. Using neo-Schumpeterian framework, this paper firstly tries to explain the difference between Brazilian technological and innovational sectorial pattern and those of the leader countries. Once settled this distinction, a sample of shipyards which took part on the uplift is analyzed, according to the technological strategies they adopted in order to be able to do so. This effort is inspired by Freeman (1975) and Vermulm (1994). The conclusions are that, while shipbuilding is a scale- intensive industry in the leader countries, it is suppliersdominated in Brazil. In terms of individual firms, there is heterogeneity of strategies, which are path-dependents. At last, there is an attempt to classify the firms on our own taxonomy
136

A indústria de construção naval: uma abordagem estratégica. / The shipbuilding industry: a strategic approach.

Cunha, Marcus Sá da 29 September 2006 (has links)
A abordagem estratégica de uma indústria é fundamentada no conhecimento dos mecanismos que regulam a competição dentro da mesma. As empresas participantes de qualquer indústria, de forma racional ou não, procuram um posicionamento favorável em relação aos seus concorrentes, de forma usufruir vantagens competitivas que se traduzam em rentabilidades superiores. Portanto, torna-se necessária a formulação de uma estratégia que é um caminho viável que conduzirá uma empresa a este posicionamento. As empresas da indústria naval competem entre si pelas encomendas dos armadores. Estes por sua vez tentam impor o seu poder de barganha exigindo menores preços e padrões de qualidade superiores. Na outra extremidade encontram-se os fornecedores que procuram capitalizar para si uma parcela do valor gerado pela indústria nos preços dos insumos fornecidos. Em meio a essas pressões, o ambiente competitivo do setor sofre a permanente ameaça da chegada de novos concorrentes, dispostos a lutar por uma fatia do mercado; sem dizer a possibilidade de embate com produtos ou serviços substitutos com desempenho equivalente. A arena desta competição é internacional, pois a construção naval é uma indústria global, ou seja, a posição estratégia de um estaleiro em um país é fortemente influenciada pela sua posição competitiva em outros países. Além disso, cabe ressaltar que além deste escopo global de competição, o seu ambiente econômico é estruturalmente cíclico, altamente influenciado pelos ciclos de desenvolvimento da economia mundial. No momento presente a indústria vive um momento de euforia, com preços aquecidos e carteiras de encomendas que garantem produção para mais de três anos para os principais construtores mundiais. É nesse momento de otimismo que a TRANSPETRO, a companhia de navegação da Petrobrás, lança um ousado programa para renovação e ampliação de sua frota de petroleiros, colocando uma licitação para a construção de 42 navios em estaleiros nacionais, com o objetivo subsidiário de estimular a revitalização da indústria naval brasileira. O fato é que o fracasso dos planos de construção naval (PCN) ao final da década de 70 ainda está na memória nacional. A indústria brasileira após alcançar a vice-liderança mundial assistiu o seu próprio colapso em meio à recessão mundial provocada pelas crises do petróleo em 1973 e 1979. Martin Stopford, diretor-presidente da Clarkson Research, afirma que o atual momento da indústria é uma espécie de ?super ciclo?, porém não há indícios que esteja surgindo um novo paradigma. Embora a indústria esteja em um patamar sem precedentes ela deverá experimentar a seguir períodos de desaquecimento. Pensar em estratégia para concorrer na indústria naval é pensar no longo prazo, ou seja, como diz o Professor Stopford: é necessário olhar além dos ciclos. / The strategic approach of any industry is grounded on the knowledge of the mechanisms which regulate the competition within this industry. The players, based on reason or not, try to achieve an advantageous position relative to the others, so as to take competitive advantages, which implies in superior profits. Therefore, it is necessary to formulate a strategy, a viable way which will lead a company to this position. The companies within the shipbuilding industry compete for the orders from the shipowners. These shipowners try to bargain so as to get lower prices and higher quality. On the other corner, we have the suppliers trying to capitalize upon the shipbuilders so as to improve their profits for the sale of the equipments and industrialized materials. Within this competitive environment there is another threaten, the arrival of new comers, ready to try to get a piece of the market. There is also the possibility to confront to new products or services with an equivalent performance. This competition takes place in an international arena, in other words the strategic position of a shipbuilder in a particular country is strongly affected for its competitive position in other countries. Furthermore, it is relevant the fact that besides the global scope of the competition, the economical environment of the industry is structurally cyclic, highly influenced by the waves of global economy. At the moment, the shipbuilding industry is in a good situation with prices and orders backlogs which guarantee production for more than three years to the greatest world shipbuilders. It is in this moment of great optimism that TRANPETRO, the PETROBRÁS shipping company, launches an audacious program to renew and expand its tanker fleet, presenting a bid to order 42 tankers in national shipyards, with the side effect of stimulating the revitalization of the Brazilian shipbuilding industry. The point is: the failure of two Naval Construction Plans (PCN), at the end of seventies, is still in mind. The Brazilian Shipbuilding Industry reached the second place in world just before to assist its own collapse in the middle of a world recession, caused by the crude oil crisis in 1973 and 1979. Martin Stopford, chairman of Clarkson Research, affirms that the current moment is a kind of ?super cycle?, but there is no evidence of a new paradigm. Although the industry is in a level without precedents, this period will be followed by a through. Thinking in strategy to compete in shipping industry means thinking in long terms, or, as Professor Stopford says: it is necessary to look beyond the cycles.
137

Desenvolvimento de uma ferramenta para direcionamento no fornecimento de navipeças pela indústria brasileira sob a ótica da Visão Baseada em Recursos (VBR). / Development of a tool to guide companies for the ship parts selling, under the Resource-Based View (RBV).

Anderson, Valdir Lopes 22 July 2011 (has links)
Diversos empresários e órgãos de classe procuram identificar oportunidades no desenvolvimento potencial dos setores naval e offshore e no fornecimento de conteúdo local para essas indústrias. Também as instituições governamentais e privadas interessadas no fomento à indústria brasileira procuram formas de conferir competitividade à indústria alvo de suas políticas. Este trabalho desenvolve de forma preliminar uma ferramenta suportada pela teoria da Visão Baseada em Recursos (VBR), que visa identificar a similaridade entre os recursos necessários para produzir uma série de equipamentos e as competências detidas pela firma. Além da identificação da similaridade, que permite priorizar a escolha dos equipamentos que podem ser desenvolvidos pela firma interessada em atuar no mercado naval, a ferramenta permite a identificação de lacunas tecnológicas e traz à baila importantes discussões sobre a obtenção de competências externamente à firma. / Several entrepreneurs and unions seek to identify potential development opportunities in marine and offshore industries, aiming to provide local content for these industries. Also the government and private institutions interested in promoting the Brazilian industry endeavor ways to give competition to the shipbuilding industry. This study develops a preliminary tool supported by the theory of Resource-Based View (RBV), which aims to identify the similarity between the resources needed to produce a series of equipment and the capabilities held by the firm. Besides the identification of similarity, which helps on the choice of equipment to be developed by the firm, the tool allows the identification of technology gaps and brings up important discussions about getting capabilities outside the firm boundaries.
138

Fire Characteristics of Cored Composite Materials for Marine Use

Grenier, Andrew T. 01 May 2002 (has links)
A material study was conducted on two types of cored composite materials used in shipbuilding: a GRP/Balsa Cored sandwich and a GRP/PVC Foam Cored sandwich. The two materials were tested in the Cone Calorimeter and the LIFT Apparatus to obtain data on ignitability, heat release rate, mass loss rate, and smoke production. The observed phenomena of delamination, melting and charring of the core materials, and edge effects are discussed in the context of how they affect test results. The ignition data analysis method specified in ASTM E 1321 "Standard Test Method for Determining Material Ignition and Flame Spread Properties" and Janssens' "improved" method of analysis were both used to derive effective material properties of the test materials. These two analysis methods are shown to produce different material property values for critical irradiance for ignition, ignition temperature, and the effective thermal property, $k ho c$. Material properties derived using Janssens' method are shown to be more consistent between the two test materials and the two different test methods; they were also shown to be better predictors of time to ignition when compared to actual test data. Material properties are used as input to Quintiere's fire growth model in order to evaluate their affect on time to flashover predictions in the ISO 9705 Room/Corner test scenario. Recommendations are made for future testing of cored composite materials, ignition data analysis methods, predictive fire growth models, and other work with composite materials. ** This copy contains no figures or appendices **
139

Damage detection and damage evolution monitoring of composite materials for naval applications using acoustic emission testing

Angelopoulos, Nikolaos January 2017 (has links)
Maritime transport has profound importance for the world economy. Vessels of all sizes constantly transport large numbers of passengers and goods across the sea, often under adverse operational conditions. Vessels need to exhibit high levels of reliability, availability, maintainability and safety (RAMS). However, at the same time their performance needs to be optimised ensuring the lowest possible fuel consumption with the maximum operational capacity and range without compromising RAMS. Sweating of naval assets and profitability should be maximised for the operator ensuring investment in future projects and supporting the growth of maritime transport and world economy as a whole. Vessels have been traditionally manufactured using naval steel grades such AH, DH and EH. Smaller leisure and specialised purpose vessels such as patrol boats, etc. have been built using fibre-reinforced composite (FRC) materials. This trend is gradually penetrating the market of larger commercial vessels including freight and cruise ships. However, these are still the early days and further investigation of the optimum FRC manufacturing techniques and mechanical properties together with an in-depth understanding of the damage mechanics are required before such materials can become more commonplace. This project has investigated different glass FRCs using different manufacturing techniques. Glass fibres are preferred due to their lower cost in comparison with carbon fibres. The use of carbon FRCs in maritime applications is limited to the fabrication of racing and high performance speedboat vessels. Samples manufactured under laboratory conditions have been compared with those manufactured by a shipyard. It has been seen that the in-house samples had generally superior performance. Steel-to-composite joints have also been assessed including different designs. The effect of different features in the design such as drilled holes and bolts on the mechanical performance of the manufactured samples has also been evaluated. The damage mechanisms involved during damage propagation and features causing damage initiation have been considered. Damage initiation and subsequent evolution have been monitored using acoustic emission (AE). Various signal processing approaches have been employed (manual and automatic) for optimum evaluation of the AE data obtained in a semiquantitative manner. It has been shown that AE could be applied effectively for structural health monitoring of naval structures in the field. Several factors and parameters that need to be considered during acquisition and analysis have been successfully determined. The key results of the study together with mechanical testing and characterisation of samples employed are presented in summarised form within the present thesis.
140

Base industrial de defesa, estratégia de desenvolvimento e inserção internacional : a indústria naval civil e militar na China e no Brasil (1950-2015)

Nunes, Raul Cavedon January 2017 (has links)
Este trabalho tem como objetivo analisar a relação entre a Base Industrial de Defesa (BID) e o Desenvolvimento Econômico nacional no contexto das Relações Internacionais. Em relação ao campo de Estudos Estratégicos e Relações Internacionais, aborda-se o debate entre os teóricos da Revolução em Assuntos Militares (caráter disruptivo das inovações tecnológicas e militares) e os advogados das Gerações da Guerra (caráter evolutivo das inovações tecnológicas e militares), suas decorrências para a análise do Poder Naval, para a polaridade do Sistema Internacional e para a inserção internacional dos países. Após a análise dos principais autores e teorias que abordam a existência de uma sinergia entre esses aspectos da realidade, adotou-se como estudos de caso a indústria naval civil e militar na China e no Brasil, de forma a averiguar tendências e indicadores que corroborem, ou não, as teorias supracitadas. Conclui-se que há de fato possibilidades de sinergia entre a BID e o desenvolvimento econômico, o que pode ser inferido pelos casos estudados. Entretanto, o modelo de desenvolvimento escolhido, os Arranjos Institucionais entre Estado, setor privado e terceiro setor, e as parcerias estratégicas internacionais variam entre os países, gerando resultados diferenciados quanto à modernização tecnológica e à ampliação da escala produtiva. Neste sentido, os conceitos de Sistema Nacional de Inovação (SNI), Clusters, Complexo Militar-Industrial e Cooperação Técnica Internacional auxiliam na análise dos aspectos auxiliares da sinergia entre a BID e a estratégia de desenvolvimento. / This study aims to analyze the relationship between the Defence Industrial Base (DIB) and the Economic Development in the context of International Relations. Concerning the Strategic Studies and International Relations fields, it aproaches the debate between the Revolution on Military Affairs (disruptive aspects of technological and military innovations) and the proponents of the generations of warfare (evolutionary character of technological and military innovations) and its consequences for naval power analysis, for the polarity of the international system, and for foreign policy. After the analysis of the main authors and theories that approach the synergy between these aspects, two case studies were adopted to verify trends and indicators that could corroborate or not the aforementioned theories: China’s and Brazil’s civilian and military shipbuilding. The findings of this exercise is that there are possible synergies between the DIB and Economic Development, which can be inferred from the case studies. However, the development model, the institutional arrangements between State, the private sector, the third sector, and the International Strategic Partnerships vary between countries, generating different results for the technological modernization and scale of production. In this sense, the concepts of National Innovation System (NIS), Clusters, Military-Industrial Complex and International Technical Cooperation assist in the analysis of the management aspects of synergy between DIB and the Development Strategy.

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