Minimizing Total Earliness and Tardiness for Common Due Date Single-Machine Scheduling with an Unavailability Interval

This paper addresses the problem of scheduling n independent jobs on a single machine with a fixed unavailability interval, where the aim is to minimize the total earliness and tardiness (TET) about a common due date. Two exact methods are proposed for solving the problem: mixed integer linear programming formulations and a dynamic programming based method. These methods are coded and tested intensively on a large data set and the results are analytically compared. Computational experiments show that the dynamic programming method is efficient in obtaining the optimal solutions and no problems due to memory requirement

避免暫時瓶頸漂移之晶圓投料法

[[abstract]]產品投料時程若控制不當，在非瓶頸製程步驟可能形成新的暫時瓶頸，此現象會間接導致原來瓶頸的缺貨，或是使得根據原始瓶頸製程步聚所訂定的投料時程無法達到預期的效果。本研究針對半導體晶圓製造廠環境，發展一個避免暫時瓶頸漂移的投料方法，比較用避免飢餓法（SA）所得到的投料計畫，與用本文所提之投料修正法產生的投料計畫，以實際晶圓製造廠生產模擬模型驗證，模擬結果顯示本文所提的方法能顯著縮短生產週期時間，降低關鍵非瓶頸機臺（受到監控的非瓶頸機臺）之在製品量，並保持系統的產出率在既定的水準。 [[abstract]]The order releasing methods currently available for avoiding bottleneck starvation assume that non-bottleneck machines have sufficient capacity to subordinate the releasing schedule. Although this assumption is theoretically true (due to the definition of a bottleneck), in practice, non-bottleneck machines may temporarily at some time window) lack adequate capacity to subordinate the planned releasing schedule. In other words, either a new bot- tleneck or bottleneck shifting subsequently occurs. This new bottleneck, if the production planner lacks advanced knowledge of bottleneck shifting and does not take appropriate corrective actions, adversely affects the original bottleneck performance and total production performances. Therefore, in this study , we present a bottleneck shifting averting order releasing method to resolve the above problems. The proposed method's effectiveness is confirmed by comparing it with the available SA order releasing methods. Three production performance measurements, i.e., cycle time, throughput rate and WIP level for those models are taken and compared

A Systematic Evaluation Model for Solar Cell Technologies

Fossil fuels, including coal, petroleum, natural gas, and nuclear energy, are the primary electricity sources currently. However, with depletion of fossil fuels, global warming, nuclear crisis, and increasing environmental consciousness, the demand for renewable energy resources has skyrocketed. Solar energy is one of the most popular renewable energy resources for meeting global energy demands. Even though there are abundant studies on various solar technology developments, there is a lack of studies on solar technology evaluation and selection. Therefore, this research develops a model using interpretive structural modeling (ISM), benefits, opportunities, costs, and risks concept (BOCR), and fuzzy analytic network process (FANP) to aggregate experts' opinions in evaluating current available solar cell technology. A case study in a photovoltaics (PV) firm is used to examine the practicality of the proposed model in selecting the most suitable technology for the firm in manufacturing new products