A Multi-Stage Graph Model Analysis for the International Toxic Waste Disposal Conflict

A generic conflict model is developed to analyze international toxic waste disposal issues, and then, to provide feasible strategic resolutions for this serious environmental dispute. With the rapid growth of the global economy, toxic waste traffic from the advanced to developing nations has become a serious side effect of this globalization. The illegal transboundary movement of toxic wastes not only aggravates the burden on the poorer nations, but also negatively impacts the worldwide environment. In this thesis, the ongoing toxic waste disputes are divided into two stages consisting of the dumping prevention and dispute resolution stages. The analyses based on the methodology of Graph Model for Conflict Resolution are used in both stages in order to grasp the structure and implications of the conflict from a strategic viewpoint. The in-depth modeling of the toxic waste dumping disputes, which consist of historical and generic situations, specifies the involved parties and their options. By synthesizing the economic, political and legal factors, the relative preferences for each party can be determined. The Graphical User Interface (GUI) of the Decision Support System (DSS) GMCR II simplifies the processing of calculations. The analytical research furnishes investigators or other interested parties with possible resolutions for the disputes arising from an international waste dumping event. Sensitivity analyses are also conducted to provide a comprehensive understanding of the different situations that may occur in real-world cases. The case study of the Ivory Coast waste dumping controversy is used to demonstrate how to practically implement the generic multi-stage graph model

Optimal Scheduling of Trains on a Single Line Track

This paper describes the development and use of a model designed to optimise train schedules on single line rail corridors. The model has been developed with two major applications in mind, namely: as a decision support tool for train dispatchers to schedule trains in real time in an optimal way; and as a planning tool to evaluate the impact of timetable changes, as well as railroad infrastructure changes. The mathematical programming model described here schedules trains over a single line track. The priority of each train in a conflict depends on an estimate of the remaining crossing and overtaking delay, as well as the current delay. This priority is used in a branch and bound procedure to allow and optimal solution to reasonable size train scheduling problems to be determined efficiently. The use of the model in an application to a 'real life' problem is discussed. The impacts of changing demand by increasing the number of trains, and reducing the number of sidings for a 150 kilometre section of single line track are discussed. It is concluded that the model is able to produce useful results in terms of optimal schedules in a reasonable time for the test applications shown here

Visual analytics of flight trajectories for uncovering decision making strategies

In air traffic management and control, movement data describing actual and planned flights are used for planning, monitoring and post-operation analysis purposes with the goal of increased efficient utilization of air space capacities (in terms of delay reduction or flight efficiency), without compromising the safety of passengers and cargo, nor timeliness of flights. From flight data, it is possible to extract valuable information concerning preferences and decision making of airlines (e.g. route choice) and air traffic managers and controllers (e.g. flight rerouting or optimizing flight times), features whose understanding is intended as a key driver for bringing operational performance benefits. In this paper, we propose a suite of visual analytics techniques for supporting assessment of flight data quality and data analysis workflows centred on revealing decision making preferences