| Summary: | 碩士 === 國立清華大學 === 工業工程研究所 === 84 === In this paper, we propose several heuristics to schedule
independent jobs in unrelated parallel machine systems. We
limit our scope to the static and deterministic problem. The
system we investigate consists of several different types of
machines, and machines of different types are unrelated and
machines of the same type are identical. Both the total
lateness and total tardiness problem in this thesis are
formulated into mathematical programming models. Nevertheless,
an optimal solution may not be available; and in practice, all
that is required may be just a near-optimal solution. The
proposed heuristics contain two phases: The first phase is to
allocate jobs onto machines or subsystems. The second phase is
to sequence the jobs on each machine or in each subsystem. The
first phase consists of two stages: the constructing stage and
the allocating stage. The constructing stage is to construct an
initial job list which is used as reference to allocate jobs.
The allocating stage is to allocate jobs onto machines or
subsystems by balancing machine workload or by the criterion
taking performacne measure directly into account. The second
stage is composed of the sequencing stage which determine the
final processing order of jobs on each machine. For the total
lateness problem, the SPT rule is adopted to determine the
final job sequence; for the total tardiness problem, the TPI
rule is adopted in this stage.
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