Two-echolon vehicle routing problem with customs decision and time window: A case study

Businesses and supply chains depend heavily on routing decisions, transit times, and costs. Sales, trustworthiness, and fulfilling deadlines are essential to the success of any business. Sales might be affected by transportation expenses, but customers also value timely shipment. Companies gain trust and favor in this setting when they demonstrate that they can be counted on to deliver as promised. It includes the requested and carried out customs procedures that take place over an extended period of time, especially in the context of international shipping. Although customs procedures have been made more flexible for movement from Turkey to Europe, waiting times still vary due to the fact that customs-cleared products can only be transported from certain points and because of congestion at customs stations during different times. Both the sender and the recipient can save money and time by organizing cars according to the estimated transportation time, cost, and route information. On time delivery is especially important for bulky raw materials and semi-finished commodities that must be processed at the receiving factory. This research presents a Vehicle Routing Model subject to time and capacity limitations, where cargoes are moved using homogeneous vehicles leaving a single depot, and then travel to one of two customs points before being delivered to clients at full or partial vehicle capacity. We evaluate the generated model to real-world events and evaluate real data collected from a transportation firm.The mixed integer programming model was used to simulate a wide variety of delivery schedules and consumer populations. When evaluating the model with the input data, the results show a 70% reduction in expenses. Furthermore, in order to assess the suitability of the model for extensive datasets, symmetric datasets were generated in R Studio, wherein the elements corresponded to estimates of pairwise distances between sequences within a given set. The model was subsequently re-solved using CPLEX, and the outcomes were assessed.