Johanna Törnquist

Agent-Based Approaches to Transport Logistics

This paper provides a survey of existing research on agent-based approaches to transportation and traffic management. A framework for describing and assessing this work will be presented and systematically applied. We are mainly adopting a logistical perspective, thus focusing on freight transportation. However, when relevant, work of traffic and transport of people will be considered. A general conclusion from our study is that agent-based approaches seem very suitable for this domain, but that this still needs to be verified by more deployed system.

Train Traffic Deviation Handling Using Tabu Search and Simulated Annealing

This paper addresses the problem of solving conflicts in railway traffic that arise due to disturbances. It is formulated as a problem of re-scheduling meets and overtakes of trains and has been dealt with in a two-level process. The upper level handles the order of meets and overtakes of trains on the track sections while the lower level determines the start and end times for each train and the sections it will occupy. A linear optimization model is used in the lower level process and provides the upper level with dual prices of the binding constraint in order to generate potentially good alternative meets and overtakes, i.e. generating a suitable neighborhood to the current solution. Simulated Annealing (SA) and Tabu Search (TS) have been applied separately on the top level. The values of their generated solutions were compared to the optimum, showing that TS outperformed SA.

Inter-Organization Interoperability in Transport Chains Using Adapters Based on Open Source Freeware

The significance of electronic information exchange in transport chains and its influence on the performance of the logistics processes is well-known. While much focus is still on the various techniques for information exchange, many Small and Medium-sized Enterprises (SMEs) experience problems that are not primarily caused by an absence of technology. Several advanced solutions exist but investment possibilities within many SMEs are very limited while their needs for electronic data exchange may be very similar as for the large companies. We describe a general “adapter” solution based on open source freeware that make it possible (in principle) for any business system to exchange information with any other business system. It has been successfully applied in a pilot study involving two companies (the transport operator being an SME) using different business systems (Hogia Mobilast and Movex). The solution was evaluated with the result that it met the requirements of the companies and is now planned to be used for future data exchange between the companies.

Enemy at the gates : Introduction of Multi-Agents in a Terminal Information Community.

Container terminals in Europe play a significant role as nodes within logistics chains. The management of container transportation system is a decentralized, often poorly structured, complex, and changeable problem domain, Therefore we propose that a Multi-Agent System (MAS) approach would offer port and terminal actors (e.g. rail operators), a suitable means of control, coordination, and management in the container terminal domain, Ports, as nodes, accept and deliver freight from various modes of transport and offer services that ald value to the freight. In order to plan the activities in the terminals, continuous and reliable information on the cargos’ physical status (e.g. position, condition) is paramount to other activities. Integrating the information flows from the various transport providers and actors would improve the planning for the terminals and benefit planning and scheduling for the others in the chain. Through the