| Summary: | 碩士 === 國立臺灣大學 === 工業工程學研究所 === 87 === This research develops a hierarchical shop floor control system
for semiconductor factoies. The control system reduces the
complexity of the scheduling problems.And dynamically allocates
resources properly. In fact, the system use dynamic machine
assignment and load balance strategies to achieve an optimal
resource distribution, under unstable manufacturing circumstances.
There are three level defined in the hierarchical system structure.
The upper level is a non-identical parallel machine(NIPM) micro
scheduler for forecasting the capacity of each tunnel, by using
the integer programming methods. The middle level is changeover
time considered a load balance controller, which is responsible
for optimalizing utilization in each Tunnel. Proper workload is
distributed to each machine considering the batches in the stocker
and the current status of the machine. The bottom level is an
intelligent real-time dispatcher, which sorts the processing
sequence for the batches queued in each machine. The dispatching
strategy is developed as a Real-time-Decision-Tree that has the
capabilities of binary-seperation, sorting, batching. The processing
sequence is sorted by the Depth-First tree searching method.
The embedded dispatching rule based has the characteristics of
multi-objective, real-time response, flexible-construct, and
matching the characteristics of each production area.
In addition, based on the distributed structure of the widely used
MES system, the shop floor control system is implemented in
MS Visual C++ programming language. The software system provides
a simulation environments of the real semiconductor factory to
verify the superiority of the developed shopfloor control system
to meet the requirements of high machine efficiency and product
diversity.
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