An Integrated Model of Continuous Review Inventory and Vehicle Routing Problem with Time Windows

Öz

Item stock-out or shortage is a great issue for customer satisfaction and can be countered by providing safety stocks. This study discusses an authorized distributor of smartphone and tablet computer products in Indonesia. Currently, the company is considering a plan to take over the role of a logistics service company to reduce the total logistics costs that must be incurred by making improvements in terms of inventory management. Inventory management can also protect the company from the impact of inflation and price increases that will impose logistics costs. This study has assumed that the vehicle travel speed or travel time between two nodes is fixed. This study contributes to minimizing total logistics costs by integrating the concept of a continuous review lot size-reorder point (Q, R) inventory model with lost sales and vehicle routing problems with time windows (VRPTW). Continuous review (Q, R) inventory model with lost sales shows the retailers’ cycle demand ranges from 130 to 234 units. This condition leads to the value of the expected average annual inventory cost IDR 27.263.204.625,59. Based on the VRPTW calculation, the total distribution cost per trip is IDR 445.631.642,7. Based on the current total distribution costs, it was found that the total distribution costs were IDR 849.454.616,2, so there is a decrease in distribution costs of 47.54%. The total logistics cost that must be incurred by the company to deliver smartphone products to 10 retailers in Jakarta and its surrounding areas is IDR 27,708,836,268.29. 

Anahtar Kelimeler

• Continuous Review
• Vehicle Routing
• Logistics Cost

Kaynakça

1. Andiyan, Putra, R. M., Rembulan, G. D., & Tannady, H. (2021). Construction project evaluation using CPM-crashing, CPM-PERT and CCPM for minimize project delays. Journal of Physics: Conference Series, 1933(1), 1-7. https://doi.org/10.1088/1742-6596/1933/V012096 google scholar
2. Chopra, S., & Meindl, P. (2016). Supply chain management: strategy, planning, and operation (6th ed.). Pearson Education. google scholar
3. Christian, M., Dewi, D., Rembulan, G. D., Indriyarti, E. R., Wibowo, S., & Yuniarto, Y. (2021). Business performance determinants of salted fish distribution in Kapuk during the COVID-19. Journal ofDistribution Science, 19(6), 29-39. https://doi.org/10.15722/jds.19.6.202106.29 google scholar
4. Demirbilek, M. (2021). A-static-periodic solution strategy for dynamic vehicle routing problem with simultaneous pickup and delivery. Acta Infologica, 5(1), 1-12. https://doi.org/10.26650/acin.831973 google scholar
5. Dey, B. K., Sarkar, B., Sarkar, M., & Pareek, S. (2019). An integrated inventory model involving discrete setup cost reduction, variable safety factor, selling price dependent demand, and investment. RAIRO - Operations Research, 53(1), 39-57. https://doi.org/10.1051/ro/2018009 google scholar
6. Dixit, A., Mishra, A., & Shukla, A. (2019). Vehicle routing problem with time windows using meta-heuristic algorithms: A survey. Advances in Intelligent Systems and Computing, 741, 539-546. https://doi.org/10.1007/978-981-13-0761-4_52 google scholar
7. Dzhelil, Y., Mihalev, T., Ivanov, B., & Dobrudzhaliev, D. (2022). Mathematical modeling and optimization of supply chain for bioethanol. Acta Infologica, 6(1), 33-42. https://doi.org/10.26650/acin.817655 google scholar
8. Gholami, A., & Mirzazadeh, A. (2018). An inventory model with controllable lead time and ordering cost, log-normal-distributed demand, and gamma-distributed available capacity. Cogent Business and Management, 5(1), 1-17. https://doi.org/10.1080/23311975.2018.1469182 google scholar

9. Gmira, M., Gendreau, M., Lodi, A., & Potvin, J. Y. (2021). Tabu search for the time-dependent vehicle routing problem with time windows on a road network. European Journal of Operational Research, 288(1), 129-140. https://doi.org/10.1016/j.ejor.2020.05.041 google scholar
10. Gunawan, F. E., Wilujeng, F. R., Rembulan, G. D., & Tannady, H. (2020). Service quality analysis of SMEs tempe in province of Jakarta, Indonesia. Technology Reports of 'Kansai University, 62(7), 3827-3833. google scholar
11. Gutierrez-Rodriguez, A. E., Conant-Pablos, S. E., Ortiz-Bayliss, J. C., & Terashima-Marin, H. (2019). Selecting meta-heuristics for solving vehicle routing problems with time windows via meta-learning. Expert Systems with Applications, 118, 470-481. https://doi.org/10.1016/j.eswa.2018.10.036 google scholar
12. Heizer, J., Render, B., & Munson, C. (2020). Operations management: sustainability and supply chain management (13th ed.). Pearson. google scholar
13. Keskin, M., Çatay, B., & Laporte, G. (2021). A simulation-based heuristic for the electric vehicle routing problem with time windows and stochastic waiting times at recharging stations. Computers and Operations Research, 125, 1-15. https://doi.org/10.1016/j.cor.2020.105060 google scholar
14. Kouki, C., Babai, M. Z., Jemai, Z., & Minner, S. (2019). Solution procedures for lost sales base-stock inventory systems with compound Poisson demand. International Journal of Production Economics, 209, 172-182. https://doi.org/10.1016/j.ijpe.2018.01.021 google scholar
15. Liu, C., Kou, G., Zhou, X., Peng, Y., Sheng, H., & Alsaadi, F. E. (2020). Time-dependent vehicle routing problem with time windows of city logistics with a congestion avoidance approach. Knowledge-Based Systems, 188. https://doi.org/10.1016/j.knosys.2019.06.021 google scholar
16. Montororing, Y. D. R., & Nurprihatin, F. (2021). Model of quality control station allocation with consider work in process, and defect probability of final product. Journal ofPhysics: Conference Series, 1-12. https://doi.org/10.1088/1742-6596/1811/1/012013 google scholar
17. Mukherjee, A., Dey, O., & Giri, B. C. (2019). An integrated imperfect production-inventory model with optimal vendor investment and backorder price discount. Advances in Intelligent Systems and Computing, 699, 187-203. https://doi.org/10.1007/978-981-10-7590-2_14 google scholar
18. Nahmias, S., & Olsen, T. L. (2021). Production & operation analytics (8th ed.). Waveland Press Inc. google scholar
19. Nurprihatin, F., Andry, J. F., & Tannady, H. (2021). Setting the natural gas selling price through pipeline network optimization and project feasibility study. Journal ofPhysics: Conference Series, 1-6. https://doi.org/10.1088/1742-6596/1811/1/012008 google scholar
20. Nurprihatin, F., Elnathan, R., Rumawan, R. E., & Regina, T. (2019). A distribution strategy using a two-step optimization to maximize blood services considering stochastic travel times. IOP Conference Series: Materials Science and Engineering, 650(1). https://doi. org/10.1088/1757-899X/650/1/012043 google scholar
21. Nurprihatin, F., Elvina, Rembulan, G. D., Christianto, K., & Hartono, H. (2021). Decision support system for truck scheduling in logistic network through cross-docking strategy. Journal of Physics: Conference Series, 1-10. https://doi.org/10.1088/1742-6596/1811/1/012009 google scholar
22. Nurprihatin, F., Gotami, M., & Rembulan, G. D. (2021). Improving the performance of planning and controlling raw material inventory in food industry. International Journal of Research in Industrial Engineering, 10(4), 332-345. https://doi.org/10.22105/riej.2021.306872.1250 google scholar
23. Nurprihatin, F., Jayadi, E. L., & Tannady, H. (2020). Comparing heuristic methods’ performance for pure flow shop scheduling under certain and uncertain demand. Management and Production Engineering Review, 11(2). https://doi.org/10.24425/mper.2020.133728 google scholar
24. Nurprihatin, F., & Lestari, A. (2020). Waste collection vehicle routing problem model with multiple trips, time windows, split delivery, heterogeneous fleet and intermediate facility. Engineering Journal, 24(5), 55-64. https://doi.Org/10.4186/ej.2020.24.5.55 google scholar
25. Nurprihatin, F., & Montororing, Y. D. R. (2021). Improving vehicle routing decision for subsidized rice distribution using linear programming considering stochastic travel times. Journal of Physics: Conference Series, 1-8. https://doi.org/10.1088/1742-6596/1811/1/012007 google scholar
26. Nurprihatin, F., Octa, A., Regina, T., Wijaya, T., Luin, J., & Tannady, H. (2019). The extension analysis of natural gas network location-routing design through the feasibility study. Journal of Applied Research on Industrial Engineering, 6(2), 108-124. https://doi.org/10.22105/jarie.2019.174164.1082 google scholar
27. Nurprihatin, F., Regina, T., & Rembulan, G. D. (2021). Optimizing rice distribution routes in Indonesia using a two-step linear programming considering logistics costs. Journal of Physics: Conference Series, 1-8. https://doi.org/10.1088/1742-6596/1811/1/012010 google scholar
28. Nurprihatin, F., & Tannady, H. (2018). An integrated transportation models and savings algorithm to minimize distribution costs. Proceeding of the 1st Asia Pacific Conference on Research in Industrial and Systems Engineering, 216-221. https://www.researchgate.net/publication/335231165 Statistics Indonesia. (2021). Telecommunication statistics in Indonesia 2020. google scholar
29. Tannady, H., Nurprihatin, F., & Hartono, H. (2018). Service quality analysis of two of the largest retail chains with minimart concept in Indonesia. Business: Theory and Practice, 19. https://doi.org/10.3846/BTP.2018.18 google scholar
30. Xu, G. Y., Feng, J. H., Chen, F. L., Wang, H., & Wang, Z. F. (2019). Simulation-based optimization of control policy on multi-echelon inventory system for fresh agricultural products. International Journal of Agricultural and Biological Engineering, 12(2), 184-194. https://doi.org/10.25165/j. ijabe.20191202.2834 google scholar