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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.
81

Validação de protótipo e análise de falhas no teste com feixe de elétrons : um estudo visando a sua automação

Vargas, Fabian Luis January 1991 (has links)
O trabalho aqui apresentado descreve algumas pesquisas em teste de circuitos integrados. Estas pesquisas consistem, por um lado, na análise de falhas e por outro, na validação de protótipos, ambas fazendo uso de técnicas de teste com feixe de elétrons. A primeira parte deste trabalho apresenta uma revisão dos princípios do teste com feixe de elétrons, bem como descreve as pesquisas correntemente em desenvolvimento no laboratório TIM3-INPG. Também são abordados temas como o tratamento de imagem em contraste de potencial e projeto visando a testabilidade de circuitos no teste com feixe de elétrons. Quanto a este último assunto, sua inclusão neste trabalho visou apresentar, aqueles que trabalham na área de projetos de circuitos, desconhecedores dos problemas do MEV, idéias de como realizar seu projeto a fim de tornar a tarefa de depuração do protótipo pelo feixe de elétrons o mais fácil possível. A segunda parte descreve experimentos práticos na área de validação de protótipos, onde duas técnicas pertinentes foram utilizadas e o estudo de um caso real foi apresentado. A primeira técnica é baseada na adaptação de uma ferramenta de comparação de múltiplas imagens adjacentes, que foi originalmente desenvolvida para o processo de análise de falhas. A segunda técnica utilizada faz uso de um sistema especialista que, baseado no conhecimento adquirido do circuito, gera o diagnóstico automático de falha. Os desempenhos destas duas ferramentas são apresentados e discutidos, bem como é fornecido o diagnóstico de falha para o circuito protótipo utilizado. Como conclusão, são propostos futuros desenvolvimentos no processo de validação de protótipo. Estes melhoramentos objetivam tanto a completa automação do processo quanto o enriquecimento da informação provida no final do processo de diagnóstico de falha, de forma a obter-se um ambiente de teste para validação de protótipos apresentando um alto grau de integração e automação. / The work reported herein describes some IC testing research. This research concerns on one hand, failure analysis and on the other hand IC prototype validation, both making use of e-beam testing techniques. The first part of this work presents a review of e-beam testing as well as describes the researches currently in progress at the TIM3-INPG Laboratory. Subjects like voltage contrast image treatment and design for testability in e-beam testing are also discussed. Considering the last theme, it was included in this work in order to provide to the IC designers, whose knowledge about the SEM problems is not enough, some ideas on the way of how to accomplish their design to make the prototype validation process as easy as possible. The second part describes practical experiments in the prototype validation domain, where two approaches were used and a real case study was presented. The first approach is based on the multiple adjacent images comparison process adaptation, firstly developed to be used in the failure analysis process. The second technique makes use of an expert system, based on the acquired knowledge of the device under test in order to provide the fault diagnosis. The performances of these two approaches are presented and discussed, as well as, the fault diagnosis to the prototype circuit is presented. As conclusion, it is proposed further developments in the prototype validation approach. These improvements deal with the automation of the entire process as well as the enhancement of the information provided at the end of the fault diagnosis process, in order to obtain a testing environment for prototype validation with high integration and automation degrees.
82

Sistematização de problemas e práticas da análise de falhas potenciais no processo de desenvolvimento de produtos / Systematization of problems and practices of potential failure analysis in the process of new product development

Rafael Laurenti 23 July 2010 (has links)
A análise de falhas potenciais compreende o uso de técnicas sistemáticas (métodos) durante o Processo de Desenvolvimento de Produto (PDP) que utilizam conhecimentos tácitos de engenharia para prever possíveis falhas, tanto do projeto (design) do produto quanto de seu processo de fabricação, e propor ações que evitem a ocorrência dessas falhas. O problema prático que motiva a realização deste trabalho é a dificuldade enfrentada pelas empresas em alcançar plenamente todos os benefícios decorrentes da aplicação da análise de falhas potenciais. O exame do estado da arte indica que há diversos problemas e práticas propostas para minimizar esses problemas dispersos na literatura. Existem também empresas benchmark na aplicação de métodos de análise de falhas potenciais que podem ser estudadas para o levantamento de outras práticas. Assim, o trabalho tem como objetivo sistematizar os problemas e práticas presentes na literatura e práticas empregadas por uma empresa benchmark. A fim de atingir esse objetivo, são gerados dois resultados principais. O primeiro, alcançado por meio de uma Revisão Bibliográfica Sistemática, é o agrupamento dos problemas e das práticas de análise de falhas potenciais presentes na literatura em categorias. Os 37 problemas encontrados foram agrupados em: Definição do risco, Recursos, Integração PDP, Temporal, Cultura organizacional, Gestão de informações, Procedimentos e Comportamental; e as 161 práticas em Abordagem, Ferramenta, Framework, Método, Software e Diretriz. O segundo resultado, obtido a partir de um estudo de caso, são práticas empregadas por uma empresa que é referência na aplicação dos métodos de análise de falhas potenciais FMEA (Failure Mode and Effects Analysis) e DRBFM (Design Review Based on Failure Mode). Os resultados do estudo de caso sugerem que o sucesso da execução dos métodos FMEA e DRBFM, na unidade de negócio caso, deve-se à combinação de provisão de recursos, trabalho em equipe multidisciplinar, formação de competências (treinamento), definição de procedimentos, aplicação integrada com outros métodos/ferramentas do PDP, e, sobretudo, não considerar a aplicação como atividade pro forma. Os conhecimentos gerados nesse trabalho podem contribuir para auxiliar as empresas a alcançarem os benefícios da aplicação de métodos de análise de falhas potenciais no processo de desenvolvimento de produtos. / The potential failure analysis is the application of systematic techniques (methods) in the process of New Product Development (NPD) that make the use of tacit engineering knowledge to predict possible design and manufacturing process failures and to define countermeasures. The practical problem which motivates the accomplishment of this research is the challenge companies face in achieving the full benefits that can be yield with the application of methods of potential failure analysis. The status of the research carried out in the field shows that there are many problems related to that challenge and practices proposed to mitigate these problems, dispersed in the literature. Notwithstanding the practices later cited, benchmark companies in applying methods of potential failure analysis can be investigated for discovering more practices. The goal of this study is to systematize both the problems and practices reported in the literature and the practices adopted by a benchmark company. In meeting that goal, this research delivered two main outcomes. First, through a Systematic Literature Review, is the sorting of the problems and practices cited in the literature. The 37 problems found were categorised in the classes: Definition of risk, Resources, NPD integration, Moment, Organizational culture, Information management, Procedures and Behavioural; and the 161 practices in Approach, Tool, Framework, Method, Software and Guideline. The second outcome, accomplished through a case study, is a set of practices employed by a company which is reference in applying the FMEA (Failure Mode and Effects Analysis) e DRBFM (Design Review Based on Failure Mode) methods. The findings suggest that the successful execution of the FMEA and DRBFM methods, in the business unit case, is due to a combination of provision of resources, employing multi-disciplinary teams, training, defining and documenting the process of application, integrating the application of these methods with others NPD methods/tools, and, mainly, not considering the application a perfunctory task. It is believed that the knowledge resulted from this research might assist companies to get benefits from the methods of potential failure analysis applied into the process of new product development.
83

Análise inteligente de falhas para apoiar decisões estratégicas em projetos de sistemas críticos. / Intelligent analysis of failure that supports strategic decision-making in critical systems projects.

Adilson de Oliveira 13 October 2009 (has links)
Este trabalho propõe o uso de Sistemas de Informação e Inteligência Empresarial visando a Análise Inteligente de Falhas para Apoiar Decisões Estratégicas em Projetos de Sistemas Críticos. Tal proposta estabelece uma correlação entre a dinâmica proveniente de recursos e ferramentas de Sistemas de Informação e Inteligência Empresarial, e a necessidade de se obter informações precisas, em intervalos de tempo aceitáveis para agregar valores tangíveis na segurança, confiabilidade, disponibilidade e mantenabilidade de Sistemas Críticos. A proposta aqui apresentada vem ao encontro da necessidade premente de disponibilizar, com maior eficácia, informações precisas para a aferição de indicadores importantes ao Projeto de Sistemas Críticos, e favorecer a implementação de ações mitigadoras de falhas que possam vir a comprometer o funcionamento desses sistemas. De forma a completar e consolidar a proposta em questão desenvolveu-se um ambiente computacional, utilizando-se dos fundamentos teóricos e das melhores práticas de Sistemas de Informação e Inteligência Empresarial, com as especificidades inerentes a Sistemas Críticos. Avaliou-se tal ambiente em um estudo de caso desenvolvido no Sistema Metroviário de São Paulo. Esse estudo de caso contribuiu, no aspecto conceitual, com a realização de ensaios de análises qualitativas e quantitativas de falhas, fornecendo informações relevantes para apoiar possíveis decisões estratégicas no sistema estudado. / This work proposes the use of Information Systems and Business Intelligence aiming an Intelligent Analysis of Failure that supports Strategic Decision Making in Critical Systems Projects. This proposition establishes a correlation between the dynamics of resources and tools from Information Systems and Business Intelligence, and the need to obtain accurate information within an acceptable time interval to add tangible value in security, reliability, availability and maintainability of Critical Systems. The proposition presented here meets the need to provide, more efficiently, accurate information to measure relevant indicators of the projects in Critical Systems, and favor the implementation of failure mitigating actions that could come to compromise the functioning of these systems. In order to complete and consolidate the proposition in question, a computational environment was developed, making use of the theoretical bases and of the best practices of Systems of Information and Business Intelligence, with the peculiarities inherent to Critical Systems. Such environment was evaluated in a case study in the Metrorail Company of São Paulo State, in which qualitative and quantitative analysis of failures were tested, providing relevant information to support possible strategic decisions in the system studied.
84

Analyse des circuits intégrés par laser en mode sonde / Integrated circuit analysis by laser probing techniques

Rebaï, Mohamed Mehdi 08 December 2014 (has links)
Les travaux de recherche présentés dans ce manuscrit de thèse ont pour principal objectif d’aider à comprendre les différents mécanismes et phénomènes qui interviennent lors de l’interaction d’un laser avec un semiconducteur dans une analyse de circuits intégrés submicroniques. Le but étant de maitriser et améliorer les techniques d’analyse par laser en mode sonde. La miniaturisation et la densification des composants électroniques fait que les techniques d’analyse par laser atteignent leurs limites. Connaitre l’impact des différents paramètres physiques, optiques et électriques sur une analyse sonde est un facteur clé pour pouvoir améliorer la compréhension des signaux sonde mesuré. Ces travaux montrent également l’effet non négligeable de la température sur les techniques d’analyse par laser en mode sonde. / The main objective of the presented research work in this PhD thesis is to help to understand the different mechanisms and phenomena involved in the interaction of a laser with a semiconductor in the analysis of a submicron integrated circuit. The aim is to master and improve the Electro Optical Probing techniques. Miniaturization and densification of electronic components lead the failure analysis techniques using Laser to their limits. Knowing the impact of different physical, optical and electrical parameters on a probing analysis is a key to improve the understanding the measured EOP signals. These studies also show the significant effect of temperature on the EOP techniques.
85

Analyse multimodale et multicritères pour l'expertise et la localisation de défauts dans les composants électriques modernes / multimodal and multi-criteria analysis for the expertise and locating faults in modern electrical components

Boscaro, Anthony 20 November 2017 (has links)
Ce manuscrit de thèse illustre l’ensemble des travaux de recherche répondant aux problématiques de traitement des données issues des techniques de localisation de défauts. Cette phase de localisation étant une étape déterminante dans le processus d’analyse de défaillances des circuits submicroniques, il est primordial que l’analyste exploite les résultats de l’émission de lumière et du sondage laser. Cependant, ce procédé d’expertise reste séquentiel et dépend uniquement du jugement de l’expert. Cela induit une probabilité de localisation non quantifiée. Afin de pallier ces différents défis, nous avons développé tout au long de cette thèse, une méthodologie d’analyse multimodale et multicritères exploitant le caractère hétérogène et complémentaire des techniques d’émission de lumière et de sondage laser. Ce type d’analyse reposera sur des outils de haut niveau tels que le traitement du signal et la fusion de données, pour au final apporter une aide décisionnelle à l’expert à la fois qualitative et quantitative.Dans un premier temps, nous détaillerons l’ensemble des traitements utilisés en post-acquisition pour l’amélioration des données 1D et 2D. Par la suite, l’analyse spatio-temporelle des données en sondage laser sera explicitée. L’aide décisionnelle fera l’objet de la dernière partie de ce manuscrit, illustrant la méthode de fusion de données utilisée ainsi que des résultats de validation. / The purpose of this manuscript is to exhibit the research work solving the issue of data processing stem from defect localization techniques. This step being decisive in the failure analysis process, scientists have to harness data coming from light emission and laser techniques. Nevertheless, this analysis process is sequential and only depends on the expert’s decision. This factor leads to a not quantified probability of localization. Consequently to solve these issues, a multimodaland multicriteria analysis has been developped, taking advantage of the heterogeneous and complementary nature of light emission and laser probing techniques. This kind of process is based on advanced level tools such as signal/image processing and data fusion. The final aim being to provide a quantitive and qualitative decision help for the experts.The first part of this manuscript is dedicated to the description of the entire process for 1D and 2D data enhancement. Thereafter, the spatio-temporal analysis of laser probing waveforms will be tackled. Finally, the last part highlights the decision support brought by data fusion.
86

Backside observation of large-scale integrated circuits with multilayered interconnections using laser terahertz emission microscope

Yamashita, Masatsugu, Otani, Chiko, Kawase, Kodo, Matsumoto, Toru, Nikawa, Kiyoshi, Kim, Sunmi, Murakami, Hironaru, Tonouchi, Masayoshi 13 May 2009 (has links)
No description available.
87

Linear And Nonlinear Progressive Failure Analysis Of Laminated Composite Aerospace Structures

Gunel, Murat 01 January 2011 (has links) (PDF)
This thesis presents a finite element method based comparative study of linear and geometrically non-linear progressive failure analysis of thin walled composite aerospace structures, which are typically subjected to combined in-plane and out-of-plane loadings. Different ply and constituent based failure criteria and material property degradation schemes have been included in a PCL code to be executed in MSC Nastran. As case studies, progressive failure analyses of sample composite laminates with cut-outs under combined loading are executed to study the effect of geometric non-linearity on the first ply failure and progression of failure. Ply and constituent based failure criteria and different material property degradation schemes are also compared in terms of predicting the first ply failure and failure progression. For mode independent failure criteria, a method is proposed for the determination of separate material property degradation factors for fiber and matrix failures which are assumed to occur simultaneously. The results of the present study show that under combined out-of-plane and in-plane loading, linear analysis can significantly underestimate or overestimate the failure progression compared to geometrically non-linear analysis even at low levels of out-of-plane loading.
88

Progressive Failure Analysis Of Composite Shells

Olcay, Yasemin 01 February 2012 (has links) (PDF)
The objective of this thesis is to investigate the progressive failure behavior of laminated fiber reinforced composite shell structures under different loading conditions. The laminates are assumed to be orthotropic and the first order shear deformation theory is applied. Three-node layered flat-shell elements are used in the analysis. To verify the numerical results obtained, experimental and analytical results found in literature are compared with the outputs of the study, and the comparison is found to have shown good agreement with the previous work. Rectangular graphite/epoxy composite laminates under transverse loading are analyzed through several boundary conditions and stacking sequences. Maximum stress criteria, Hashin&rsquo / s criteria and Tsai Wu criteria are employed to detect the failure and progressive failure methodology is be implemented according to instantaneous degradation approach. First ply failure, final failure loads, corresponding deformations and failure patterns are presented and compared.
89

Using Telemetry to Measure Equipment Mission Life on the NASA Orion Spacecraft for Increasing Astronaut Safety

Losik, Len 10 1900 (has links)
ITC/USA 2012 Conference Proceedings / The Forty-Eighth Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2012 / Town and Country Resort & Convention Center, San Diego, California / The surprise failure of two NASA Space Shuttles and the premature failures of satellite subsystem equipment on NASA satellites are motivating NASA to adopt an engineering discipline specifically developed for preventing surprise equipment failures. The NASA Orion spacecraft is an Apollo module-like capsule planned to replace the NASA Space Shuttle reusable launch vehicle for getting astronauts to space and return to the earth safely as well as a crew escape vehicle stored at the ISS. To do so, NASA is adopting a non-Markov reliability paradigm for measuring equipment life based on the prognostic and health management program on the Air Force F-35 Joint Strike Fighter. The decision is based on the results from the prognostic analysis completed on the Space Shuttle Challenger and Columbia that identified the information that was present but was ignored for a variety of reasons prior to both accidents. The goal of a PHM is to produce equipment that will not fail prematurely and includes using predictive algorithms to measure equipment usable life. Equipment with transient behavior, missed by engineering analysis is caused from accelerated of parts will fail prematurely with 100% certainty. With the processing speed of today's processors, transient behavior is caused from at least one part suffering from accelerated aging. Transient behavior is illustrated in equipment telemetry in a prognostic analysis but not in an engineering analysis. Telemetry is equipment performance information and equipment performance has been used to increase reliability, but performance is unrelated to equipment remaining usable life and so equipment should be failing prematurely. A PHM requires equipment telemetry for analysis and so analog telemetry will be available from all Orion avionics equipment. Replacing equipment with a measured remaining usable life of less than one year will stop the premature and surprise equipment failures from occurring during future manned and unmanned space missions.
90

Stopping Launch Vehicle Failures Using Telemetry to Measure Equipment Usable Life

Losik, Len 10 1900 (has links)
Launch vehicle equipment reliability is driven by infant mortality failures, which can be eliminated using a prognostic analysis prior, during and/or after the exhaustive and comprehensive dynamic environmental factory acceptance testing. Measuring and confirming equipment performance is completed to increase equipment reliability by identifying equipment that fails during test for repair/replacement. To move to the 100% reliability domain, equipment dynamic environmental factory testing should be followed by a prognostic analysis to measure equipment usable life and identify the equipment that will fail prematurely. During equipment testing, only equipment performance is measured and equipment performance is unrelated to equipment reliability making testing alone inadequate to produce equipment with 100% reliability. A prognostic analysis converts performance measurements into an invasive usable life measurement by sharing test data used to measure equipment performance. Performance data is converted to usable life data provides a time-to-failure (TTF) in minutes/hours/days/months for equipment that will fail within the first year of use, allowing the production of equipment with 100% reliability.

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