Chapter Objective Chapter Outline

Abdul Samad Shibghatullah 16 30052008 Chapter Two: Literature Reviews and Interviews

2.1 Introduction

The research at this point tries to understand the UE problem, how to deal with it in detail, and tries to see current crew scheduling approaches and whether they have mechanisms for dealing with UE. The information will help to identify limitations in dealing with UE and will be used as a foundation to propose a suitable approach to deal with such problems. Then the research also justifies the choice of a MAS as a suitable tool to implement the approach. To achieve the above aim, we do a literature survey to find information on UE, to evaluate current crew scheduling approaches, and to justify the use of a MAS. Also, we perform interviews with three bus companies to obtain empirical information about the UE problem, the current scheduling system in use, and how to deal with UE. Findings from literature and interviews will identify the research gap and then the proposed approach in Chapter Three is our attempt to fill the gap.

2.1.1 Chapter Objective

The objectives of Chapter Two are to present information gathered from the literature survey and interviews, to identify a theoretical gap based on critiques of current Abdul Samad Shibghatullah 17 30052008 approaches and proposes a MAS as a suitable approach to tackle this gap. This proposal is then put as the research question to be tackled throughout the rest of the dissertation. Three types of information are gathered from the literature survey: the UE problem and ways of tackling it, current approaches in regard to dealing with UE, and a MAS as a suitable implementation tool. The interviews give information on practical experiences of bus companies in managing their daily operations and dealing with UE, how crews are rescheduled manually, and the current system that they use. Interviews with Bus Companies Current Approaches -heuristics, mathematical, others Motivations to Use MAS -current approaches have limitations -need a tool that provides quick results in uncertain environment Critiques to Current Approaches -no mechanism to deal with UE -if there is still has limitations Interview Analysis -UE take place anytime -supervisor has many responsibilities -current system does not support crew rescheduling -manual way is hard and slow, prone to errors, not optimal MAS Details -agents and MAS, MAS interaction, MAS communication -the use of MAS in scheduling UE problems in Literature Research Question -Is MAS a suitable approach for automated crew rescheduling system? Literature Review Describing the Interviews Empirical Review Figure 2.1: The Structure of Chapter Two

2.1.2 Chapter Outline

Section 2.1 started with an introduction to Chapter Two, its objectives, and outline see Figure 2.1. Section 2.2 presents an overview of the UE problem, its sources and how to deal with them in the literature. Thereafter, Section 2.3 presents the definition of crew Abdul Samad Shibghatullah 18 30052008 scheduling problems and then examines the three groups of most commonly used approaches in crew scheduling problems: heuristics, mathematical programming, and other approaches. These approaches are evaluated with respect to their abilities to deal with the UE problem. Section 2.4 presents the interviews with bus companies, and the