Using Degradation-with-Jump Measures to Estimate Life Characteristics of Lithium-Ion Battery

Degradation-with-jump measures are time series data sets containing the information of both continuous and randomly jumping degradation evolution of a system. Traditional maximum likelihood estimation and Bayesian estimation are not convenient for such general jump processes without closed-form distributions. Based on general degradation models derived using Lévy driven non-Gaussian Ornstein-Uhlenbeck (OU) processes, we propose a systematic statistical method using linear programing estimators and empirical characteristic functions. The point estimates of reliability function and lifetime moments are obtained by deriving their explicit expressions. We also construct bootstrap procedures for the confidence intervals. Simulation studies for a stable process and a stable driven OU process are performed. In the case study, we use a general Lévy process to fit the Li-ion battery life data, and then estimate the reliability and lifetime moments of the battery. By integrally analyzing degradation data series embedded with jump measures, our work provides the efficient and precise estimation for life characteristics

Reliability deployment in distributed manufacturing chains via closed-loop Six Sigma methodology

This paper proposes a Six Sigma based framework to deploy high product reliability commitment in distributed subcontractor manufacturing processes. The study aims to expand the Six Sigma tools in applications, where products are designed and developed under the fast time-to-market requirement. The reliability deployment is driven by two incentives: the customer satisfaction and the reduction of the warranty cost. A closed-loop control mechanism is created between the upper and the lower manufacturing streams to identify and remove the early life failures occurred during the initial system installation. A cross-functional team is formed to implement Six Sigma tools for resolving critical failures arising in the upper manufacturing stream. The ultimate goal is to achieve high product reliability in the shortest time when the product time-to-market is essential for gaining the market share. Finally, the proposed control mechanism is demonstrated on the system designs drawn from the semiconductor testing industry.Six Sigma program Reliability growth Distributed supply chain Subcontract manufacturing Capital equipment