應用線性規劃於電子元件廠投料模式之構建

Abstract

本研究以電子元件廠為對象，發展一細部生產計畫的投料模式。以極小化平均流程時間和未達交率為目標式；以訂單需求量和在製品存量為計畫生產量，再加入工廠的機台產能限制、產品製程加工順序、關鍵物料備齊時間和產品只能在特定機台加工等因素，利用線性規劃求得每天產品投料量和產出量的最佳解。 根據目標式中的參數值(α,β)做實驗設計，分析其參數值對平均流程時間、未達交率、總延遲天數和平均延遲天數等相關績效的影響。實驗結果顯示：(1)當α愈大時，未達交率愈高，平均流程時間、平均生產週期時間及平均延遲天數較短。(2)當β愈大時，平均延遲天數愈長，未達交率和總延遲天數愈短。 本研究所提出的投料微調機制，可以將零散的製造工單微調後做為實際投料表，而微調後的生產投料表仍符合原先線性規劃中的限制式。對於電子元件製造廠實際運用線性規劃做生產投料排程而言，更具實用價值。

This study develops a releasing model using linear programming for a Taiwaness electronic component factory. The objective function is to minimize mean flow time and unfilled rate. Customer orders and WIP information are the major inputs. Factory characteristics including machine capacity, routing plan, critical material kittable date, and specific manufacturing constraints( such as some products can only be processed on certain machines) are taking into consideration. Daily release plan and output plan are then obtained. An experiment is designed. The impacts of parameters (α,β) on the performance of the mean flow time, unfilled rate, total delayed time, and mean delayed time are analyzed. The results show that (1)when α value grows, the unfilled rate becomes higher, while the mean flow time, mean cycle time, and mean delayed time become shorter, and (2)When β value increases, the mean delayed time, unfilled rate, and total delayed time are smaller. This study also proposes schedule adjusting rules. These rules make the production quantity more realistic. After the adjustment, the new schedule still satisfies the constraints of the linear programming model. This adjusting mechanism is more useful for the studied electronic component factory.