Estimation of absolute error for the resources-constrained project scheduling problem
نویسندگان
چکیده
We consider some special cases of the NP -hard resource-constrained project scheduling problem (RCPSP ) to minimize the makespan. We conjecture that the ratio of the optimal makespan of RCPSP to that of the preemptive version of the problem is less than 2. We show that a well-known lower bounds for the problem may yield bad approximation ratios or its calculation is an NP -hard problem too. We also provide some new estimates of the optimal makespan of RCPSP .
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