Multistate Reliability Model and Quality Loss Analysis

本研究将动态多状态可靠性模型与质量损失分析相结合，将产品性能退化描述为时间的函数。在这种建模方法中，产品性能水平被表示为产品设计参数和环境因素在任何给定时间的函数。定义一个质量损失函数，用来衡量一段时间内的产品性能水平。然后，模型和损失函数导致可靠性驱动的产品参数设计、产品性能评估、可靠性驱动的产品公差设计以及可靠性和鲁棒性设计的集成。该研究部分建立在与福特汽车公司合作的基于可靠性的机动车辆系统蒸发排放的工作基础上，将蒸发排放作为典型的性能退化问题。通过与福特汽车公司的合作，通过将理论研究与基于1995年及以后车型年机动车辆燃料系统蒸发排放的实际可靠性研究相结合，可以验证这项研究的结果。这项研究将有助于汽车制造商达到《清洁空气法》规定的蒸发排放新标准，该标准由美国环保署和加州空气资源委员会制定。它还将开发可靠性驱动产品设计的技术，并提出可以更广泛使用的稳健设计集成策略。

9500126 Yang This research integrates dynamic multistate reliability model and quality loss analysis in order to describe the product performance degradation as a function of time. In this modeling approach the product performance level is expressed as the function of product design parameters and environmental factors at any given time. A quality loss function which measures the product performance level over a time period will be defined. The model and loss function then lead to reliability-driven product parameter design, product performance evaluation, reliability-driven product tolerance design, and reliability and robust design integration. The research is partially built upon work in collaboration with the Ford Motor Company on reliability-base motor vehicle system evaporative emission, using evaporative emission as a typical performance degradation problem. Collaboration with Ford Motor Company allows the results of this research to be validated by combining the theoretical research with a practical reliability-based study of a motor vehicle fuel system's evaporative emission for 1995 and subsequent model years. This research will contribute to motor vehicle manufacturers' ability to meet new standards for evaporative emission governed by the Clean Air Act and set by the EPA and the California Air Resource Board. It will also develop techniques for reliability-driven product design and suggest robust design integration strategies that can be used more generally.