In 2002, Aguilera et al. analyzed the performance of the disjunctive lift-and-project operator defined by Balas, Ceria and Cornuéjols on covering and packing polyhedra, in the context of blocking and antiblocking duality. Their results generalize Lovász’s Perfect Graph Theorem and a theorem of Lehman on ideal clutters. This study motivated many authors to work on the same ideas, providing alter...

This paper describes new local photometric descriptors based on dissociated dipoles for transformed images or rigid objects retrieval. Dissociated dipoles are non local differential operators proposed by Balas et al. [1] which have been proved to be more stable than purely local standard differential operators. In this paper, we define and compute specific oriented dissociated dipoles around mu...

Intersection cuts are a family of cutting planes for pure and mixedinteger linear programs, developed in the 1970s. Most papers on them consider only cuts that come from so-called maximal lattice-point-free polyhedra. We define a completely different family of intersection cuts, called “natural”. Their key property is that they can be generated very quickly and easily from a simplex tableau. In...

Untuk sesuatu rekaan, pembinaan serta ujian jentera-jmtera memproses dan mesin-mesin pengangkutan bahan-bahan biological, sifat-sifat mekanikal bahan-bahan tersebut perlu diketahui terlebeh dahulu. Oleh kerana percubaan-percubaan yang lampau dapat mempastikan bahawa bahan-bahan biological bersifat viscoelastic, perlulah ianya dinyatakan supaya dapat dipastikan tindak balas sifat-sifat tersebut ...

Aguilera et al. [DiscreteAppl.Math. 121 (2002) 1–13] give a generalization of a theorem of Lehman through an extension P̄j of the disjunctive procedure defined by Balas, Ceria and Cornuéjols. This generalization can be formulated as (A) For every clutter C, the disjunctive index of its set covering polyhedron Q(C) coincides with the disjunctive index of the set covering polyhedron of its blocker...

In the seventies, Balas introduced intersection cuts for a Mixed Integer Linear Program (MILP), and showed that these cuts can be obtained by a closed form formula from a basis of the standard linear programming relaxation. In the early nineties, Cook, Kannan and Schrijver introduced the split closure of an MILP, and showed that the split closure is a polyhedron. In this paper, we show that the...

A linear programming-based heuristic procedure for solving Multiple choice Programming (MCP) problems is presented. Two pivot schemes which may be viewed as the specialized versions of those in “Pivot and Complement”, an &icicnt heuristic by Balas and Martin for pure O-l programming, are inuxporatai into the procedure along with the additional features of cut generation, variable fixing and uch...

Our senses can process only a limited amount of the incoming sensory information. In the human visual system this becomes apparent in the reduced performance in the peripheral field of view, as compared to the central fovea. Recent research shows that this loss of information cannot solely be attributed to a spatially coarser resolution but is essentially caused by statistical pooling operation...