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Optimization and Approximation in Deterministic Sequencing and Scheduling: a Survey
TLDR
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
TLDR
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
TLDR
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
TLDR
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
TLDR
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
TLDR
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
TLDR
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
TLDR
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
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