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With the rapid development fo electronic products, the demand fro IC chips is increasing. IC packaging thus is getting more and more important. Due to the OEM production type, today, most IC pacaging factories face the problems that orders are arrived dynamically and mot easy to be forecasted. Therefore. the key point of mid-term production planning of the IC packaging factories is to plan the flexible production lines such that the capacities among lines can be adjusted. In the thesis, the mid-term production planning is executed through two models, production lines allocating and orders accepting. To allocate system capacities to prouction lines, the concept of group technology and theory of constraint is used so as to reduce setup times. Then, following the result of production lines allocating, the bottleneck machine utilization rate is set to plan the daily releasing quantities in each line. This justifies that orders accepting is fit for the planned capacities in each line. To find out the capacity for handling the variability of order arrivals, a short-term production lines capacity adjusting model is designed. When the actual order arrival is different from the planned one, the numbers of bottleneck machines are adjusted between production lines considering the capacity needed for actual order arrivals. Running the model for different cases, we can observe the degree of variability that the system can handle so as to make sure the feasibility of the mid-term proluction planning. This degree of variablity is then used as reference for setting the bottleneck utilization rate in next planning horizon. To verify the performance of proposed mid-term production planning system, an example is tested. The simulation results indicate that this model can provide at least 30% flexibility to handle the dynamically arrived orders given that the total capacity requirement is fixed. Also, the lead time can be decreased effectively by the releasing strategy.
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