A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Civil Engineering

Thesis (M.Eng.) - Asian Institute of Technology, 2005

Bangkok like other major cities of Asia, is developing at a very fast pace, coupled with increasing passenger and freight traffic. Government of Thailand has built public truck terminals along with introducing large truck bans to improve intra city freight traffic. This study introduces a Cooperative Delivery System (CDS) as a city logistic measure. The proposed CDS consists of a common stock point where goods are brought in by various participating companies and are consolidated; routes are then optimized at common stock point in a cooperative environment using Vehicle Routing Problem with Time Windows (VRP-TW) model. A MATLAB program code is developed to apply Genetic Algorithm (GA) to solve VRP-TW. Furthermore as a safe guard against the fears of small freight companies participating in CDS, of being side lined or losing their chances of advertisement through their trucks; Truck Assigning Module (TAM) is developed, which assigns consolidated routes back to the trucks of participating companies. It was shown through modeling results that CDS is capable of improving load factors and reliability along with considerable cost savings. CDS was found effective in distribution environment with larger demands at clients, but it was in lesser demand distribution environment where CDS was able to increase the load factor by a large percentage and thus it was able to reduce significant number of routes as compared to non-cooperative delivery system. In non-cooperative environments with smaller sized deliveries, freight carriers often have to make compromises on lesser load factors and more routes to satisfy the time windows of clients. Reducing number of routes not only reduces cost of distribution it also means less number of trucks on roads, with corresponding improvement in traffic conditions and decrease in on street parking. This could be a very important factor considering the narrow sois of Bangkok. CDS was also found proficient in reducing penalties, specially the delay penalty; this reduction not only saves cost but it also improves the reliability of freight carriers. Based on the modeling results obtained, this study can be used as an evaluation measure for future application of CDS in Bangkok. Considerable cost savings and potential increase in reliability can be showed to freight carriers as incentives to join CDS. TAM performed extremely well, it was able to distribute the consolidated routes of cooperative environment to the trucks of participating companies. Though in some instances a company had to take more routes than those it was running in non-cooperative environment, but as the overall cost of the solution was less in CDS, it would always get more benefits than whatever extra resources it would invest.