An indirect search algorithm for disaster restoration with precedence and synchronization constraints

Akifumi Kira,Yutaka Kimura,Katsuki Fujisawa,Hirokazu Anai,Hidenao Iwane

doi:10.1186/s40736-017-0032-5

Abstract

When a massive disaster occurs, to repair the damaged part of lifeline networks, planning is needed to appropriately allocate tasks to two or more restoration teams and optimize their traveling routes. However, precedence and synchronization constraints make restoration teams interdependent of one another, and impede a successful solution by standard local search. In this paper, we propose an indirect local search method using the product set of team-wise permutations as an auxiliary search space. It is shown that our method successfully avoids the interdependence problem induced by the precedence and synchronization constraints, and that it has the big advantage of non-deteriorating perturbations being available for iterated local search.

Highlights

In the wake of the Great East Japan Earthquake, hands-on research and development is required to solve concrete social problems
We propose an enhanced indirect search method which uses the product set of team-wise permutations as an auxiliary search space, though many successful indirect search algorithms use permutations as an auxiliary search space
3 Proposed method we develop an enhanced indirect search algorithm that avoids the interdependence problem induced by the precedence and synchronization constraints

Summary

Introduction

In the wake of the Great East Japan Earthquake, hands-on research and development is required to solve concrete social problems. To repair the damage to the networks as fast as possible, planning is needed to appropriately allocate tasks to two or more restoration teams and optimize their traveling routes Such a scheduling problem is a variant of the vehicle routing problem (VRP) which designs optimal delivery or collection routes from one or several depots to a number of geographically scattered customers. The first systemic studies of this problem using VRPs in the context of Japan, appears to be Watanabe et al [9, 10] In these case studies, the problem is formulated as a VRP with time windows (VRPTW) and standard local search heuristics are applied. The results obtained from numerical examples in this study are described

The case study

Decoder

Conclusion and future work