Models and valid inequalities to asymmetric skill-based routing problems

Improved Solutions for Inventory- Routing Problems through Valid Inequalities and Input Ordering

Valid inequalities based on the interpolation procedure

We study the interpolation procedure of Gomory and Johnson (1972), which generates cutting planes for general integer programs from facets of cyclic group polyhedra. This idea has recently been re-considered by Evans (2002) and Gomory, Johnson and Evans (2003). We compare inequalities generated by this procedure with mixed-integer rounding (MIR) based inequalities discussed in Dash and Gunluk (...

Valid inequalities for problems with additive variable upper

We study the facial structure of a polyhedron associated with the single node relaxation of network flow problems with additive variable upper bounds. This type of structure arises, for example, in production planning problems with setup times and in network certain expansion problems. We derive several classes of valid inequalities for this polyhedron and give conditions under which they are f...

Valid Inequalities for Problems with Additive Variable Upper Bounds

We study the facial structure of a polyhedron associated with the single node re laxation of network ow problems with additive variable upper bounds This type of structure arises for example in network design expansion problems in production planning problems with setup times We rst derive two classes of valid inequalities for this polyhedron and give the conditions under which they are facet d...

Valid inequalities for a class of assembly system problems

This paper establishes a foundation for a cutting plane approach to solve a class of problems that are important to assembly systems, including assembly line balancing (ALB), workload smoothing (WS) and assembly system design (ASD). We describe relationships among the integer programming formulations of these problems and recast their relaxations as node packing problems (NPPs). Exploiting the ...