Catherine Mancel

A heuristic approach based on shortest path problems for integrated flight, aircraft, and passenger rescheduling under disruptions

In this paper, we present a heuristic method to solve an airline disruption management problem arising from the ROADEF 2009 challenge. Disruptions perturb an initial flight plan such that some passengers cannot start or conclude their planned trip. The developed algorithm considers passengers and aircraft with the same priority by reassigning passengers and by creating a limited number of flights. The aim is to minimize the cost induced for the airline by the recovery from the disruptions. The algorithm is tested on real-life-based data, as well as on large-scale instances and ranks among the best methods proposed to the challenge in terms of quality, while being efficient in terms of computation time.

3D airspace sector design by genetic algorithm

In recent years, special interest has been paid to the solution of sector design problem. The airspace is partitioned into sectors, each of them being controlled by a group of controllers. Airspace sectors should be designed cautiously, ensuring that no sector would be overloaded during the day. The objective of an airspace design process is to adapt the airspace according to the evolution of the traffic. The aim of the presented work is to propose a new global method for the sectorization of the European airspace based on a novel mathematical modeling of the airspace and heuristic optimization methods. The main purpose of this research is to develop a method for automatic airspace sectorization, which would be able to create operationally acceptable sectors.

A two level optimization approach for long-term planning in a large air transportation network

In this communication, the problem of long-term forecasting of the traffic growth in a large air transportation network is considered. This problem is crucial when planning the necessary investments in airports, fleets and air traffic control equipments. The resulting optimization problem is a multilevel one. The proposed approach makes use of two different optimization models: One model is devoted to demand forecasting, while the other defines the air transport supply according to a profit maximization behaviour of the airlines sector. The proposed solution scheme is composed of an iterative process between the current solutions of the demand and the supply optimization problems. Convergence conditions are discussed for this iterative process between these two problems which can be seen as inverse of each other. The proposed optimization approach is briefly illustrated in the case of the long-term forecasting of air traffic in the West Africa region.

Knowledge Discovery in Graphs Through Vertex Separation

This paper presents our ongoing work on the Vertex Separator Problem (VSP), and its application to knowledge discovery in graphs representing real data. The classic VSP is modeled as an integer linear program. We propose several variants to adapt this model to graphs with various properties. To evaluate the relevance of our approach on real data, we created two graphs of different size from the IMDb database. The model was applied to the separation of these graphs. The results demonstrate how the model is able to semantically separate graphs into clusters.

Optimal Allocation of Transportation Aircraft Actuators During Maneuver

In this communication we consider the problem of the design of an airborne system whose function is to solve the problem of allocation of transportation aircraft actuators during manoeuvres. The case of a roll manoeuvre, which may be quite demanding for the wings structure, is more particularly considered. The aim of this supervision function, similar to the load alleviation function, is to control the bending and flexion moments of the wings while performing a manoeuvre which can turn to be extreme. The wings actuators considered are the ailerons, the spoilers and the flaps, but the other aerodynamic actuators, elevators and rudders, must be considered to take into account the existing coupling effects between the three body axis. Their limitations, such as position, speed and response time are considered explicitly in this study.