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Optimization and Approximation in Deterministic Sequencing and Scheduling: a Survey
The state of the art with respect to optimization and approximation algorithms and interpret these in terms of computational complexity theory are surveyed. Expand
Complexity of machine scheduling problems
A classification of scheduling problems on single, different and identical machines is given and NP-completeness is established for a large number of other machine scheduling problems. Expand
Scheduling subject to resource constraints: classification and complexity
A classification scheme for resource constraints is proposed and the computational complexity of the extended problem class is investigated in terms of this classification. Expand
Deterministic Production Planning: Algorithms and Complexity
A class of production planning problems is considered in which known demands have to be satisfied over a finite horizon at minimum total costs. For each period, production and storage cost functionsExpand
Complexity of vehicle routing and scheduling problems
The complexity of a class of vehicle routing and scheduling problems is investigated and known NP-hardness results are reviewed and compiled to compile the worst-case performance of approximation algorithms. Expand
Bounds and Heuristics for Capacitated Routing Problems
Asymptotically optimal bounds and heuristics are developed for a capacitated routing problem that will find a solution with relative error at most (epsilon) in time polynomial in the number of customers. Expand
The traveling salesman problem
This study tested human performance on a real and virtual floor, as well as in a threedimensional (3D) virtual space, and modeled these results by a graph pyramid algorithm, which suggests that deterioration of performance in the 3D space can be attributed to geometrical relations between hierarchical clustering in a3D space and coarse-to-fine production of a tour. Expand
Complexity of Scheduling under Precedence Constraints
The use of precedence constraints between jobs that have to be respected in every feasible schedule is illustrated by extending some typical NP-completeness results and simplifying their correctness proofs for scheduling problems involving precedence constraints. Expand
Generating all Maximal Independent Sets: NP-Hardness and Polynomial-Time Algorithms
It is shown that it is possible to apply ideas of Paull and Unger and of Tsukiyama et al. to obtain polynomial-time algorithms for a number of special cases, e.g. the efficient generation of all maximal feasible solutions to a knapsack problem. Expand