Open shop scheduling with delays. (English) Zbl 0766.90043

Summary: The concept of interprocessor delay is introduced on the open shop model. Delays are uniform if they are always the same for any job and between any pair of machines. Scheduling an open shop with uniform delays is shown to be NP-complete even for two machines. However, if all tasks are unit execution time and the delays are uniform then a polynomial algorithm to solve the decision problem is exhibited. If the delays are nonuniform, the problem remains NP-complete.


90B35 Deterministic scheduling theory in operations research
68Q25 Analysis of algorithms and problem complexity
90C60 Abstract computational complexity for mathematical programming problems
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