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The one-dimensional cutting stock problem (1D-CSP) and the twodimensional two-stage guillotine constrained cutting problem (2D-2CP) are considered in this paper. The Gilmore-Gomory model of these problems has a very strong continuous relaxation which provides a good bound in an LP-based solution approach. In recent years, there have been several efforts to(More)
We consider two-dimensional rectangular strip packing without rotation of items and without the guillotine cutting constraint. We propose a single-pass heuristic which fills every free space in a onedimensional knapsack fashion, i.e. considering only item widths. It appears especially important to assign suitable heuristic “pseudo-values” as profits in this(More)
The primary objective in cutting and packing problems is trim loss or material input minimization (in stock cutting) or value maximization (when packing into a knapsack). However, in real-life production we usually have many other objectives (costs) and constraints. Probably the most complex auxiliary criteria of a solution are the number of different(More)
The primary objective in cutting and packing problems is trim loss or material input minimization (in stock cutting) or value maximization (when packing into a knapsack). However, in real-life production we usually have many other objectives (costs) and constraints, for example, the number of different patterns. We propose a new simple model for setup(More)
Preface Within such disciplines as Management Science, Information and Computer Science , Engineering, Mathematics and Operations Research, problems of cutting and packing (C&P) of concrete and abstract objects appear under various specifications (cutting problems, knapsack problems, container and vehicle loading problems, pallet loading, bin packing,(More)
Branch-and-Cut-and-Price (BCP) algorithms are branch-and-bound algorithms where both row generation (separation) and column generation (pricing) are performed. Following [12], we say that such an algorithm is robust when the separation and pricing subproblems are guaranteed to remain tractable during its execution. Robust BCP algorithms have been devised(More)
Constraint Programming (CP) standardizes many specialized “global constraints” allowing high-level modelling of combinatorial optimization and feasibility problems. Current Mixed-Integer Linear Programming (MIP) technology lacks both a modelling language and a solving mechanism based on high-level constraints. MiniZinc is a solver-independent CP modelling(More)
We consider several formulations of two-dimensional two-stage constrained cutting, where the number of variables is polynomial. Some new models with variable strip widths are developed. Symmetries in the search space are eliminated by lexicographic constraints which are already known from the literature. However, previously known models with fixed strip(More)