Study Of Open-loop Re-entrant Manufacturing System Based On New Parameter

With the strengthening of economic globalization trend, the market demand is diversified and the competition among enterprises is increasingly fierce. As a typical production system in the semiconductor industry, re-entrant manufacturing system has been a hotspot of research on international manufacturing industry and academia for a long time. Re-entrant characteristics, the complexity of the processing route of the re-entrant manufacturing system and larger system make the study of re-entrant manufacturing system more difficult than the traditional production system. At present, scholars study on re-entrant manufacturing system mainly from the aspects of system modeling, scheduling policy and release control, system bottleneck identification, system performance analysis, etc. Although previous scholars have made some achievements, the research results are discrete and have not been formed perfect system architecture yet. Besides, the comprehensive study of re-entrant manufacturing system has important theoretical significance and economic value on the development of semiconductor industry in China. Therefore, this article focuses on the study of the characteristics and system parameters of the open-loop re-entrant manufacturing system. In case of the actual liquid crystal production system, as a typical re-entrant production system in the semiconductor industry, this paper studies the open-loop re-entrant manufacturing system from the following aspects:system modeling and simulation, its parameters, system performance analysis, system bottleneck identification, system evaluation and optimization of scheduling policy, based on simulation modeling technology using AnyLogic software and the method of data analysis and data mining.First of all, according to re-entrant characteristics of the re-entrant manufacturing system and the ideas of discrete event simulation modeling, this paper adopts the system modeling method based on the processing route by means of AnyLogic and solves the problem of system modeling and simulation of the open-loop re-entrant manufacturing system. Furthermore, this paper proposes a new parameter, namely workstation time which described the characteristics of the open-loop re-entrant manufacturing system, through the overall analysis of the characteristics of the open-loop re-entrant manufacturing system. And the calculation formula and the definition of workstation time are given in this article which simplifies the complexity and reduces the difficulty of the research on re-entrant manufacturing system.Secondly, by analyzing the influence of workstation time, the scheduling strategy, fixed feeding interval of feeding strategy, on the performance of the open-loop re-entrant manufacturing system, this article puts forward a new method of system bottleneck identification, as well as the prediction method for the utilization of workstation and the upper bound of the system capacity of the open-loop re-entrant manufacturing system based on workstation time. And an evaluation strategy for the open-loop re-entrant manufacturing system and an optimization method for the system capacity are also come up in this paper.Finally, this paper proposes an optimal scheduling strategy based on workstation time, namely the biggest process time of the next working procedure. This article also testifies that this optimal scheduling strategy is appropriate for the open-loop re-entrant manufacturing system by means of AnyLogic simulation technology. In addition, this optimal scheduling strategy improves multiple performance of the open-loop re-entrant manufacturing system which simultaneously improves the output of system and reduces WIP, the average cycle time and the average waiting time.