Abstract

Container terminals help countries to sustain their economic development. Improving the operational efficiency in a container terminal is important. In past research, genetic algorithms (GAs) have been widely used to cope with seaside operational problems, including the berth allocation problem (BAP) and quay crane assignment problem (QCAP) individually or simultaneously. However, most GA approaches in past studies were dedicated to generate time-invariant QC assignment that does not adjust QCs assigned to a ship. This may underutilize available QC capacity. In this research, three hybrid GAs (HGAs) have been proposed to deal with the dynamic and discrete BAP (DDBAP) and the dynamic QCAP (DQCAP) simultaneously. The three HGAs supports variable QC assignment in which QCs assigned to a ship can be further adjusted. The three HGAs employ the same crossover operator but a different mutation operator and a two-stage procedure is used. In the first stage, these HGAs can generate a BAP solution and a QCAP solution that is time-invariant. The time-invariant QC assignment solution is then further transformed into a variable one in the second stage. Experiments have been conducted to investigate the effects of the three HGA and the results showed that these HGAs outperformed traditional GAs in terms of fitness value. In particular, the HGA3 with Thoros mutation operator had the best performance.

Highlights

  • Maritime transport is essential to a country as it plays a major role for international trading that can sustain economic development

  • The above literature showed that the simultaneous dynamic BAP (DBAP) and dynamic QCAP (DQCAP) have been mostly solved by genetic algorithms (GAs) approaches

  • The jth gene is an integer indicating the berth number assigned to the ship j; in the right segment the jth is an integer representing the number of QCs assigned to the ship Sj.uTsthaienatbwilitoy s2e01g9m, 1e1n, 2t0s1t8ogether indicate a total solution to the simultaneous dynamic and discrete BAP (DDBAP) and DQCAP9. of 21

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Summary

Introduction

Maritime transport is essential to a country as it plays a major role for international trading that can sustain economic development. There are three famous seaside operational problems in a container terminal They are the berth allocation problem (BAP), quay cranes assignment problem (QCAP), and quay cranes scheduling problem (QCSP). One disadvantage of a separate study is that it tends to result in poor overall system performance due to the lack of considering interrelationships among different levels of seaside operational problems simultaneously [8]. Another disadvantage found for a BAP-only study is that it often needs to assume fixed handling times for ships because these handling times cannot be estimated based on their assigned number of QCs [6].

Literature Review
Berth Plans with Different QC Assignment
The Definition of the DDBAP and DQCAP
The Mathematical Formulation of the DDBAP and DQCAP
Population Reproduction
Crossover Operation
Mutation Operation
Finding the Next Event
The Main Process Flow of the Event-Based Heuristic
The Main Process Flow of HGAs
Parameter Setting and Ship Data Generation for the Example
Comparison of Various GAs and HGAs
Findings
Conclusions
Full Text
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