Optimization of oil tanker schedules by decomposition, column generation, and time-space network techniques

Abstract

Ship scheduling problem is an important operational level planning problem in maritime logistics. In this paper, we show how we designed and developed a mathematical model for real-world tanker scheduling problem in Japan. Tanker operators own their fleet of tankers and make their schedules for the next several weeks for meeting customers' demands. However, due to the high uncertainty of the ship operations and unexpected changes of demands, the schedules has to be revised frequently. Our methodology allows the operators to determine schedules that minimize the operational cost in a few minutes. These solutions provides cost improvements for tanker operators, as measured by reduction of 5-16%.

Tramp ship routing and scheduling with integrated bunker optimization

“…In line with that, recent years have shown an increase in maritime papers that explore dynamic column generation, see e.g. Kobayashi and Kubo (2010), Hennig et al (2012) and Stålhane et al (2012). Furthermore, Desaulniers et al (2005) devoted two whole chapters to column generation in maritime problems.…”

A Mathematical Modelling and Optimization Approach for a Maritime Facility Location Transshipment Problem

“…Al-Yakoob and Sherali 2013presented a column generation heuristic for a mixed-integer programming model to find an optimal combination of vessel schedules in a multiple sources and multiple destinations scheduling scenario. Kobayashi and Kubo (2010) presented a column generation algorithm for a time-space network to solve a vessel routing and scheduling problem, where cargoes can be assigned to multiple compartments onboard vessels. Li and Pang (2011) and investigated a shipping problem where each terminal/berth handles only one vessel at a time, and proposed a set partitioning formulations and column generation techniques to solve the problem.…”

A Synchronous Optimization Model for Multiship Shuttle Tanker Fleet Design and Scheduling Considering Hard Time Window Constraint

“…= {1, tanker s carry out transport plan; 0, ℎ }. 16 : the shadow price of (16). 17 : the shadow price of (17).…”

“…Equation (25) is a (0-1) variable constraint. Because SDSA-SM is the same as the path planning problem proposed by Kobayashi and Kubo [16], the dynamic programming labeling method proposed by them can be used to solve the problem efficiently.…”