Robust Network Design for Air Transport under PSO

Alice da Silva Costa Lourenço

Key information

Authors:

Alice da Silva Costa Lourenço (Alice da Silva Costa Lourenço)

Supervisors:

Sofia Kalakou; António Ramos Andrade (António Ramos Andrade)

Published in

June 30, 2022

Abstract

Accessibility is essential for social and economic development and cohesion of regions. Thus, air transport is vital, particularly in geographically remote areas, like islands, though some routes are unprofitable due to low passenger demand. Public Service Obligations (PSO) aim to preserve those unprofitable yet vital routes, assuring that minimum transportation services are granted to those remote communities. The present work aims to develop robust tools to support the decision-making process led by the responsible authorities regarding air transport subsidized networks. Thereby, a Passenger Demand Prediction model and a robust Route and Flight Schedule Optimization program were developed. Furthermore, given the computational complexity of this optimization problem, relaxation approaches were introduced. To validate the proposed approach, it was applied to the Rhodes (Greece) based PSO network case study. First, the demand prediction results indicate that the demand in this network is affected by the population of the islands, touristic attractiveness, seasonality, and sea transport competition. It was also shown that the Covid-19 pandemic affected the impact of some of these explanatory variables. Second, it was confirmed that making only use of the expected demand to optimize the network yields a less robust solution, incapable of serving a plausibly optimistic scenario. This study contributes to the literature by accounting for different passenger demand scenarios simultaneously upon the optimization. This consideration is shown to be vital, since the optimization taking the expected demand solely into consideration, which is proposed in the literature, is unable to adapt to uncertainty inherent to demand prediction.