This paper deals with a vehicle routing problem with resource repositioning (VRPRR) which is a variation of well-known vehicle routing problem with pickup and delivery (VRPPD). VRPRR in which static repositioning of public bikes is a representative case, can be defined as a multi-objective optimization problem aiming at minimizing both transportation cost and the amount of unmet demand. To obtain Pareto sets for the problem, famous multi-objective optimization algorithms such as Strength Pareto Evolutionary Algorithm 2 (SPEA2) can be applied. In addition, a linear combination of two objective functions with weights can be exploited to generate Pareto sets. By varying weight values in the combined single objective function, a set of solutions is created. Experiments accomplished with a standard benchmark problem sets show that Variable Neighborhood Search (VNS) applied to solve a number of single objective function outperforms SPEA2. All generated solutions from SPEA2 are completely dominated by a set of VNS solutions. It seems that local optimization technique inherent in VNS makes it possible to generate near optimal solutions for the single objective function. Also, it shows that trade-off between the number of solutions in Pareto set and the computation time should be considered to obtain good solutions effectively in case of linearly combined single objective function.

1. 서 론
2. 자원 재배치 경로계획 문제
3. 다목적 해 탐색 알고리즘
    3.1 SPEA2
    3.2 가중치를 이용한 단일 목적함수
4. 실험 및 결과
    4.1 데이터 및 실험 방법
    4.2 성능 비교
    4.3 VNS 복잡성
5. 결 론
References

• Jae-Goo Kang(한남대학교 산업공학과) | 강재구
• Dong-Soon Yim(한남대학교 산업공학과) | 임동순 Corresponding Author