ISSN:0748-8017    

DOI:10.1002/qre.4680070502

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

ISSN:0748-8017    

DOI:10.1002/qre.4680070503

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

ISSN:0748-8017    

DOI:10.1002/qre.4680070504

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractFailure mechanisms associated with the effects of humidity on plastic packaged devices are briefly reviewed. Relevant experimental and theoretical work on these failure mechanisms is then considered, pointing to an incomplete understanding as to why relative humidity is the appropriate variable, along with temperature to use in acceleration factor models. The BET equation (Brunauer, Emmett and Teller), is invoked to provide a theoretical underpinning to the use of relative humidity in such acceleration factor models. The BET equation provides such a connection by relating surface concentration of water to vapour pressure of water. Using the BET equation as a starting point, we derive a relation between surface concentration of water and relative humidity that has no explicit temperature dependence.We then consider a simple kinetic model for a corrosion reaction leading to failure. The result is an acceleration factor that is a typical Arrhenius form, multiplied by a simple function of relative humidity. This form is similar to other power‐law acceleration factor models that have been developed empirically. Now a physical derivation is offered as a theoretical basis for power‐law models of the effects of humidity on plastic packaged device reliabil

ISSN:0748-8017    

DOI:10.1002/qre.4680070505

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThe business environment of the 1990s will be affected in a major way by two major catalysts for change: one driven by technology and one driven by organizational change. This paper reviews the impact of major catalysts for change expected in the 1990s. Organizational change strategies will enable a corporation to be able accurately to assess the performance and success of each engineering group in the design, manufacturing, and customer installation and life cycle support. The strategies for the development of the methods and tools and long‐term career development strategies to support the ability of the organization to catalyse change are also discussed, with the conclusion that the quality engineering profession, correctly structured and empowered, will be the driver of the successful implementation of organizational change strategies in the 1990

ISSN:0748-8017    

DOI:10.1002/qre.4680070506

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThis paper is concerned with the assessment of reliability for equipment which is highly specialized. Of particular interest is the analysis of field data early in the life of the fleet of such equipment. Factors affecting the data underlying assessments are outlined, and a basic statistical model for describing these data is introduced. Methods of assessment of equipment reliability, and the precision of such assessments, are discussed, examples of data from this basic model are analysed, and further examples illustrate the role of model parameters. The model may also be used to analyse incomplete data sets, and we consider the penalty incurred at different levels of incompleteness. The paper concludes with a discussion outlining further possible modifications and refinements to the basic model.

ISSN:0748-8017    

DOI:10.1002/qre.4680070507

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThe aim of this paper is to illustrate primarily the suitability and secondly the ability of both PHM and ‘two‐sample’ tests in answering problems in the reliability field. The findings stress the fact that ‘two‐sample’ tests should be preferred for comparison purposes and PHM for modelling the behaviour of the equipment in the presence of vari

ISSN:0748-8017    

DOI:10.1002/qre.4680070508

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractTo address the wide variety of solder joint configurations, the authors have developed and applied a physics‐of‐failure model to predicting the service life of solder joints under thermal cycling conditions. The wide variety of solder joint geometries, materials and environments makes it impractical to develop and apply empirical models to predicting the service life of solder joint interconnects. On the other hand, a physics‐of‐failure model that describes the failure mechanisms in solder joints can be applied to a wide range of conditions. The physics‐of‐failure model framework is described and a model is demonstrated for predicting the failure of a leadless surface mount solder joint under slow thermal cycling

ISSN:0748-8017    

DOI:10.1002/qre.4680070509

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThere is a variety of ways to measure the quality of knowledge work. The best selection for a particular application depends on how the user defines quality and the intended use of the measure. This paper catalogues possible measures according to five different perspectives on quality and four different uses of quality measures. It concludes with some recommendations for measuring quality in a laboratory.

ISSN:0748-8017    

DOI:10.1002/qre.4680070510

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractDuring the lifetime of any system, e.g. an electronic circuit, sources of variation of parameters include fabrication, operational and environmental (FOE) variables. Since these sources of variation are not under designer control, one important objective at the product design stage is to reduce rather than control their influence. The aim of this paper is to present a methodology whereby settings of system parameters which make product performance less sensitive to FOE variations are identified. By so doing, reliability (consistency of acceptable performance), and hence quality, is enhanced. The approach taken is to minimize performance variability subject to a constraint on yield. This objective ensures consistency of performance while the constraint ensures acceptability of performance. Multiple performances are handled via a weighted sum objective. The Monte Carlo approach ensures that any parameter probability density function is handled and that computational cost does not increase with system dimensionality. The effectiveness of the technique is illustrated via a practical system example—an electronic circuit having 11 design parameter

ISSN:0748-8017    

DOI:10.1002/qre.4680070511

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY