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This report is a tool to be used by the design engineer, manufacturer, and user to aid them in diagnosing failures in the large rolamite. It provides a tabular list of failure modes, the effect of the failure, and the degree to wh...
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This report is a tool to be used by the design engineer, manufacturer, and user to aid them in diagnosing failures in the large rolamite. It provides a tabular list of failure modes, the effect of the failure, and the degree to which the failure affects operation. (ERA citation 11:054513)
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It is assumed that the phenomenon under study is such that the time-to-failure may be modeled by an exponential distribution with failure rate lambda. For Bayesian analyses of the assumed model, the family of gamma distributions p...
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It is assumed that the phenomenon under study is such that the time-to-failure may be modeled by an exponential distribution with failure rate lambda. For Bayesian analyses of the assumed model, the family of gamma distributions provides conjugate prior models for lambda. Thus, an experimenter needs to select a particular gamma model to conduct a Bayesian reliability analysis. The purpose of this report is to present a methodology that can be used to translate engineering information, experience, and judgment into a choice of a gamma prior distribution. The proposed methodology assumes that the practicing engineer can provide percentile data relating to either the failure rate or the reliability of the phenomenon being investigated. For example, the methodology will select the gamma prior distribution which conveys an engineer's belief that the failure rate lambda simultaneously satisfies the probability statements, P(lambda less than 1.0 x 10 exp -3 ) equals 0.50 and P(lambda less than 1.0 x 10 exp -5 ) equals 0.05. That is, two percentiles provided by an engineer are used to determine a gamma prior model which agrees with the specified percentiles. For those engineers who prefer to specify reliability percentiles rather than the failure rate percentiles illustrated above, it is possible to use the induced negative-log gamma prior distribution which satisfies the probability statements, P(R(t sub 0 ) less than 0.99) equals 0.50 and P(R(t sub 0 ) less than 0.99999) equals 0.95, for some operating time t sub 0 . The report also includes graphs for selected percentiles which assist an engineer in applying the procedure. 28 figures, 16 tables. (ERA citation 02:061831)
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Failure analysis is a critical element in the integrated circuit manufacturing industry. This paper reviews the changing role of failure analysis and describes major techniques employed in the industry today. Several advanced fail...
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Failure analysis is a critical element in the integrated circuit manufacturing industry. This paper reviews the changing role of failure analysis and describes major techniques employed in the industry today. Several advanced failure analysis techniques that meet the challenges imposed by advancements in integrated circuit technology are described and their applications are discussed. Future trends in failure analysis needed to keep pace with the continuing advancements in integrated circuit technology are anticipated.
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摘要 :
Failure analysis is a critical element in the integrated circuit manufacturing industry. This paper reviews the changing role of failure analysis and describes major techniques employed in the industry today. Several advanced fail...
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Failure analysis is a critical element in the integrated circuit manufacturing industry. This paper reviews the changing role of failure analysis and describes major techniques employed in the industry today. Several advanced failure analysis techniques that meet the challenges imposed by advancements in integrated circuit technology are described and their applications are discussed. Future trends in failure analysis needed to keep pace with the continuing advancements in integrated circuit technology are anticipated.
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Research has shown that nearly 80% of the costs and problems are created in product development and that cost and quality are essentially designed into products in the conceptual stage. Currently, failure identification procedures...
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Research has shown that nearly 80% of the costs and problems are created in product development and that cost and quality are essentially designed into products in the conceptual stage. Currently, failure identification procedures (such as FMEA (Failure Modes and Effects Analysis), FMECA (Failure Modes, Effects and Criticality Analysis) and FTA (Fault Tree Analysis)) and design of experiments are being used for quality control and for the detection of potential failure modes during the detail design stage or post-product launch. Though all of these methods have their own advantages, they do not give information as to what are the predominant failures that a designer should focus on while designing a product. This work uses a functional approach to identify failure modes, which hypothesizes that similarities exist between different failure modes based on the functionality of the product/component. In this paper, a statistical clustering procedure is proposed to retrieve information on the set of predominant failures that a function experiences. The various stages of the methodology are illustrated using a hypothetical design example.
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Understanding risks and avoiding failure are daily concerns for the women and men of NASA. Although NASA's mission propels us to push the limits of technology, and though the risks are considerable, the NASA community has instille...
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Understanding risks and avoiding failure are daily concerns for the women and men of NASA. Although NASA's mission propels us to push the limits of technology, and though the risks are considerable, the NASA community has instilled within, the determination to preserve the integrity of the systems upon which our mission and, our employees lives and well-being depend. One of the ways this is being done is by expanding and improving the tools used to perform risk assessment. The Failure Environment Analysis Tool (FEAT) was developed to help engineers and analysts more thoroughly and reliably conduct risk assessment and failure analysis. FEAT accomplishes this by providing answers to questions regarding what might have caused a particular failure; or, conversely, what effect the occurrence of a failure might have on an entire system. Additionally, FEAT can determine what common causes could have resulted in other combinations of failures. FEAT will even help determine the vulnerability of a system to failures, in light of reduced capability. FEAT also is useful in training personnel who must develop an understanding of particular systems. FEAT facilitates training on system behavior, by providing an automated environment in which to conduct 'what-if' evaluation. These types of analyses make FEAT a valuable tool for engineers and operations personnel in the design, analysis, and operation of NASA space systems.
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The RTNS-II facility at LLNL uses 50 cm diameter electroformed copper targets for the production of neutrons used in the study of radiation damage of materials. One of these targets failed during a post manufacture hydrotest. This...
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The RTNS-II facility at LLNL uses 50 cm diameter electroformed copper targets for the production of neutrons used in the study of radiation damage of materials. One of these targets failed during a post manufacture hydrotest. This report identifies the causes that led to this failure, i.e., an insufficient pre-plating cleaning operation, and an interruption of the electroforming process. (ERA citation 10:007293)
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This 4-volumes report gives a background of ideas, principles, and examples which might be of use in developing practical methods for risk analysis. Some of the risk analysis techniques, described are somewhat experimental. The re...
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This 4-volumes report gives a background of ideas, principles, and examples which might be of use in developing practical methods for risk analysis. Some of the risk analysis techniques, described are somewhat experimental. The report is written in an introductory style, but where some point needs further justification or evaluation, this is given in the form of a chapter appendix. In this way, it is hoped that the report can serve two purposes, - as a basis for starting risk analysis work and as a basis for discussing effectiveness of risk analysis procedures. The report should be seen as a preliminary stage, prior to a program of industrial trials of risk analysis methods. Vol. 1 contains a short history of risk analysis, and chapters on risk, failures, errors and accidents, and general procedures for risk analysis. (Atomindex citation 12:588181)
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