Comparison of HTN Planning and OR-based Approaches for Solving Problems in Logistics Domains

Abstract

Logistics is a day-to-day real-life situation leading to a very large domain. Among the various kinds of logistics problems we encounter are those pertaining to transportation, product inventories and location. Traditionally, Operations Research (OR) techniques are used most often and are popular candidates for solving logistics problems. With the development of Hierarchical Task Network (HTN) planning algorithms, there has been a recent trend to use HTN planners to address planning problems in general. It is also envisaged that HTN planners could solve logistics problems; yet, no proof or evidence could be found as to whether this approach is more efficient or suitable to handle logistics problems. In this paper, a comparison is done to ascertain whether HTN planning could be more efficient than OR-based approaches in solving logistics problems. Results revealed that HTN planning outperforms the traditional OR-based approach, especially in solving moderate-sized and more difficult harder problems. Furthermore, HTN planning is capable of solving very large scale problems, whereas OR based approach was unable to handle them within the same computational resource limitations.Keywords: Logistics, Operations research, Hierarchical task network, Transportation simplex method, HyperTensioN