Ki Ho Chung

Development of mathematical models for the container road transportation in Korean trucking industries

Abstract This study deals with some practical problems of the container road transportation in Korean trucking industries. We examine the workflow in container transportation and then develop mathematical models integrating the various operating and design characteristics of the containers. Several types of formulations are developed utilizing the standard formulations of well known TSP (Traveling Salesman Problem) and VRP (Vehicle Routing Problem). Heuristic algorithms are also presented to solve the models. An example problem is illustrated to explain how to apply the models to the real world through the data set collected from a container trucking company in Korea.

A Study on Improving the Efficiency of Logistics Networks in Express Package Deliveries

The market competition of express package deliveries in Korea is severe because a large number of companies have entered into the market. This study thus suggests an approach to the reconfiguration of express service networks with respect to the strategy partnership of closing/keeping service centers among companies involved and the adjustments of their cutoff times. For this we propose an integer programming model and a genetic algorithm based solution procedure for allowing companies involved to maximize their incremental profit. An illustrative numerical example is presented to demonstrate the practicality and efficiency of the proposed model.

Collaborative and Sustainable Network Design in Courier Services

While the courier service demand has been continuously increasing over the last decade, the unit price has been dropping due to the more severe competition among the courier services. The courier service companies with low market share are making several types of efforts to survive in competitive market. Collaboration via the economy of sharing can allow the courier service companies to extend their service network and increase the market share. This study suggests a collaboration model to increase the competitiveness of every participating company. In addition, a nucleolus-based profit allocation method is applied for fair allocation of the profits to each participating company based on a cooperative game theory. An illustrative example problem demonstrates the applicability and efficiency of the proposed model.

A study on strategic partership-based cutoff time adjustment for express package deliveries

The market competition of express package deliveries in Korea is severe because a large number of companies have entered into the market. Under the competitive business environment, it is helpful for a company to consider how to economically operate the consolidation terminal and its corresponding service centers. In general, each company owns and operates a number of service centers in order to achieve high level service for the country-wide coverage even though some service centers cannot create profits due to low volume and under-utilization as cost centers. Such strategy is not good option for companies involved so that strategic partnership particularly in the same service districts can be an alternative way to get win-win goals while maximizing the overall operating efficiency of express service networks. Therefore, this study suggests an approach to the reconfiguration of express service networks with respect to strategy partnership of closing/keeping service centers among companies involved and adjustments of their cutoff times. For this we propose an integer programming model and a genetic algorithm based solution procedure for allowing companies involved to maximize their incremental profit. An illustrative numerical example in Korea is presented to demonstrate the practicality and efficiency of the proposed model.

Compromised network design model for the strategic alliance of service centers and consolidation terminals in express courier services

A direct shipment via express courier is expected to be an area with huge sales potential in the near future. In Korean market, many domestic companies of various sizes have been fiercely competing to extend their own market share. Currently offering only international delivery services, moreover, foreign companies with a higher level of customer services are expected to escalate the competition by entering the market of domestic delivery. These competitive rivalry and price pressure have made market conditions tough and margins under severe pressure. To cope with these substantial competition pressures, we propose strategic alliance as an effective solution to the challenges faced by small and medium express courier service companies. An integer programming model for compromised network design and its solution procedure based on maxmin and maxsum criteria are developed respectively. The applicability and efficiency of the proposed model are demonstrated through an illustrative numerical example.