In most vehicle routing and crew scheduling applications solved by column generation, the subproblem corresponds to a shortest path problem with resource constraints (SPPRC) or one of its variants. This paper proposes a classification and a generic formulation for the SPPRCs, briefly discusses complex modeling issues involving resources, and presents the most commonly used SPPRC solution method...

In this paper we consider the NP-hard problem of determining the strong metric dimension of graphs. The problem is solved by a genetic algorithm that uses binary encoding and standard genetic operators adapted to the problem. This represents the first attempt to solve this problem heuristically. We report experimental results for the two special classes of ORLIB test instances: crew scheduling ...

An ACO Inspired Strategy to Improve Jobs Scheduling in a Grid Environment p. 30 Architecture Aware Partitioning Algorithms p. 42 A Simple and Efficient Fault-Tolerant Adaptive Routing Algorithm for Meshes p. 54 Deadlock-Free Adaptive Routing in 2D Tori with a New Turn Model p. 58 Neighbourhood Broadcasting and Broadcasting on the (n, k)-Star Graph p. 70 Fault Tolerance in the Biswapped Network ...

We present a new Lagrangian-based heuristic for solving large-scale set-covering problems arising from crew-scheduling at the Italian Railways (Ferrovie dello Stato). Our heuristic obtained impressive results when compared to state of the art codes on a test-bed provided by the company, which includes instances with sizes ranging from 50,000 variables and 500 constraints to 1,000,000 variables ...

In most vehicle routing and crew scheduling applications solved by column generation, the subproblem corresponds to a shortest path problem with resource constraints (SPPRC) or one of its variants. This chapter proposes a classification and a generic formulation for the SPPRCs, briefly discusses complex modeling issues involving resources, and presents the most commonly used SPPRC solution meth...

The 3-flip neighborhood local search (3FNLS) is an excellent heuristic algorithm for the set covering problem which has dominating performance on the most challenging crew scheduling instances from Italy railways. We introduce a method to further improve the effectiveness of 3FNLS by incorporating random flat move to its search process. Empirical studies show that this can obviously improve the...

We describe the design of an optimizer for 0-1 integer programming aimed at solving large problems. The algorithm is based on very simple operations giving it a low complexity, and we show that for large set covering problems it can produce very good solutions compared to other methods. This is the only optimizer in the Carmen system for airline crew scheduling, used by several major European a...

Kliewer et al. (2006b, 2011) proposed a time window implementation to the multi-depot vehicle (and crew) scheduling problem using a time-space network (TSN). Based on this approach, we developed a new methodology to implement time windows to the vehicle-type scheduling problem (VTSP), which solves the vehicle scheduling problem considering heterogeneous fleet. Our method presents as main advant...

Crew rostering is one of the most important scheduling problems that airlines have to face regularly. The goal is to assign a set of tasks to a group of workers as fairly as possible while following various business rules. Difficulties of the optimization mainly arise from its large scale. In this paper, a modified subproblem based algorithm for the LP relaxations of crew rostering problem is p...