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961.
Bellens R. de Schrijver E. Van den Bosch G. Groeseneken G. Heremans P. Maes H.E. 《Electron Devices, IEEE Transactions on》1994,41(3):413-419
A continued fast interface trap generation is observed in n-channel MOS transistors after termination of the hot-carrier stress. The magnitude of this post-stress effect is strongly dependent on the conditions of the preceding stress, on the post-stress conditions and on the process parameters. For measurements at 293 K, a simple model is proposed which is based on the release of hydrogen by the thermal detrapping of holes, and which can explain the observed dependencies. The importance of the post-stress Dit-generation is illustrated for the case of dynamic stress conditions where it can lead to an apparently deviating degradation behavior 相似文献
962.
Load-capacity interference and the bathtub curve 总被引:1,自引:0,他引:1
Load-capacity (stress-strength) interference theory is used to derive a heuristic failure rate for an item subjected to repetitive loading which is Poisson distributed in time. Numerical calculations are performed using Gaussian distributions in load and capacity. Infant mortality, constant failure rate (Poisson failures), and aging are shown to be associated with capacity variability, load variability, and capacity deterioration, respectively. Bathtub-shaped failure rate curves are obtained when all three failure types are present. Changes in load or capacity distribution parameters often strongly affect the quantitative behavior of the failure-rate curves, but they do not affect the qualitative behavior of the bathtub curve. Neither is it likely that the qualitative behavior will be affected by the use of nonGaussian distributions. The numerical results, however, indicate that infant mortality and wear-out failures interact strongly with load variability. Thus bathtub curves arising from this model cannot be represented as simple superpositions of independent contributions from the three failure types. Only if the three failure types arise from independent failure mechanisms or in different components is it legitimate simply to sum the failure rate contributions 相似文献
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964.
An employee's failure to differentiate himself or herself from the perceived attitudes of another is at the heart of much stress in organizations. The world of family systems psychology identifies a dysfunctional process, called psychological fusion, which stems from insufficient self-definition by an individual and results in a dependency upon others to meet an innate need to feel accepted. People suffering from psychological fusion perceive any criticism as a threat, making it impossible for them to receive the critical feedback that is necessary for growth. To experience intrinsic motivation, people require a sense of relative self-determination and competence. This paper argues that much as employers take an interest in such emotional health issues as substance abuse and stress, they should also address psychological fusion; the paper offers methods for dealing with this interpersonal communications issue 相似文献
965.
The paper examines collaborative writing practices students in the Air Force Institute of Technology's Graduate School of Logistics and Acquisition Management use to produce team-authored theses. In analyzing how student writing teams plan, execute, and assess writing activities, the researchers identify and describe some of the forms that collaboration takes, thereby successfully connecting their work within a broader research continuum concerning collaborative writing, particularly when applied in academic settings 相似文献
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Reliability of software used in telecommunications networks is a crucial determinant of network performance. Software reliability (SR) estimation is an important element of a network product's reliability management. In particular, SR estimation can guide the product's system testing process and releasability decisions. SR estimation is performed using an appropriate SR estimation model. However, the art of SR estimation is still evolving. There are many available SR estimation models to select from, with different models being appropriate for different applications. Although there is no “ultimate” and “universal” SR model on the horizon (and there may not be one in the foreseeable future), methods have been developed for selecting a trustworthy SR model for each application. The present authors have been analyzing and adapting these methods for applicability to network software. Their results indicate that there already exist methods for SR model selection which are practical to use for telecommunications software. If utilized, these methods can promote significant improvements in SR management. The paper presents the results to date 相似文献
970.
Presents an overview of problems involved in introducing ISDN and new services in the public network of Poland. The technical aspects of the assumed network and services development strategy are considered. The focus is on development alternatives and the process of establishing national requirements for the development 相似文献