On the Compact Vector Summation in Stochastic Machine Scheduling
نویسندگان
چکیده
Given a fixed budget, the generic relocation problem seeks to determine a feasible reconstruction sequence of old buildings for a public housing project. The feasibility issue can be resolved because it is mathematically equivalent to makespan minimization in a two-machine flowshop. In this paper, we consider the variant where multiple working crews are available for the redevelopment project. Most of our results center on the unitexecution time (UET) situations. In this case the relocation problem is a generalization of the classical bin packing problem and can be considered as a special resource-constrained scheduling problem. We first present an NP-hardness proof for a case with two working crews and unit processing times that has remained open since 1988. Then, we design several approximation algorithms and obtain non-approximability results for different cases of relocation problem.
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