Showing papers by "Chi-Hyuck Jun published in 2000"

Performance analysis of re-entrant flow shop with single-job and batch machines using mean value analysis

Abstract: We propose an approximate method based on the mean value analysis for estimating the average performance of re-entrant flow shop with single-job machines and batch machines. The main focus is on the steady-state averages of the cycle time and the throughput of the system. Characteristics of the re-entrant flow and inclusion of the batch machines complicate the exact analysis of the system. Thus, we propose an approximate analytic method for obtaining the mean waiting time at each buffer of the workstation and a heuristic method to improve the result of the analytic method. We compare the results of the proposed approach with a simulation study using some numerical examples.

Use of contagious distributions in the semiconductor yield models considering cluster effect

Abstract: As semiconductor chips become larger, more than one cluster can be expected to form on a single chip and consequently defect density variations may be apparent not only among chips but also within a chip. In order to reflect this situation more effectively, we propose semiconductor yield models based on the contagious distributions. These models incorporate the probability that a defect or a cluster becomes fatal. Furthermore, we consider various limiting forms of the proposed contagious distribution by taking extreme values of the related parameters, A simplified form of the proposed yield formula based on the limiting distribution is also derived and its performance is compared with others using computer simulation. The proposed three yield models are shown in a simulation study to outperform alternative models based on the existing ideas.