Simultaneously lifting sets of binary variables into cover inequalities for knapsack polytopes
نویسندگان
چکیده
منابع مشابه
Simultaneously lifting sets of binary variables into cover inequalities for knapsack polytopes
Cover inequalities are commonly used cutting planes for the 0–1 knapsack problem. This paper describes a linear-time algorithm (assuming the knapsack is sorted) to simultaneously lift a set of variables into a cover inequality. Conditions for this process to result in valid and facet-defining inequalities are presented. In many instances, the resulting simultaneously lifted cover inequality can...
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We consider the family of facets of the binary knapsack polytope from minimal covers. We study previous results on sequential lifting in a unifying framework and explore a class of most violated fractional lifted cover inequalities, defined by Balas and Zemel, which are more general than traditional simple lifted cover inequalities. We investigate some theoretical properties of these inequaliti...
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We present a method of lifting linear inequalities for the flag f -vector of polytopes to higher dimensions. Known inequalities that can be lifted using this technique are the non-negativity of the toric g-vector and that the simplex minimizes the cd-index. We obtain new inequalities for 6-dimensional polytopes. In the last section we present the currently best known inequalities for dimensions...
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ژورنال
عنوان ژورنال: Discrete Optimization
سال: 2008
ISSN: 1572-5286
DOI: 10.1016/j.disopt.2007.05.003