Igor Crévits

Human‐machine cooperation: Toward an activity regulation assistance for different air traffic control levels

Our research is based on the air traffic control activity regulation assistance. It aims at integrating the two levels of the air traffic control organization: a tactical level managed by a so‐called radar controller and a strategic one managed by a so‐called organic controller. Concerning the tactical level, our research is directed toward a “horizontal cooperation” that consists in a dynamic allocation of control tasks between a human air traffic controller and an assistance tool. Regarding the other level, it is oriented toward a scheduling module in order to improve the initial allocation policy.

Iterative semi-continuous relaxation heuristics for the multiple-choice multidimensional knapsack problem

Recently several hybrid methods combining exact algorithms and heuristics have been proposed for solving hard combinatorial optimization problems. In this paper, we propose new iterative relaxation-based heuristics for the 0-1 Mixed Integer Programming problem (0-1 MIP), which generate a sequence of lower and upper bounds. The upper bounds are obtained from relaxations of the problem and refined iteratively by including pseudo-cuts in the problem. Lower bounds are obtained from the solving of restricted problems generated by exploiting information from relaxation and memory of the search process. We propose a new semi-continuous relaxation (SCR) that relaxes partially the integrality constraints to force the variables values close to 0 or 1. Several variants of the new iterative semi-continuous relaxation based heuristic can be designed by a given update procedure of multiplier of SCR. These heuristics are enhanced by using local search procedure to improve the feasible solution found and rounding procedure to restore infeasibility if possible. Finally we present computational results of the new methods to solve the multiple-choice multidimensional knapsack problem which is an NP-hard problem, even to find a feasible solution. The approach is evaluated on a set of problem instances from the literature, and compared to the results reached by both CPLEX solver and an efficient column generation-based algorithm. The results show that our algorithms converge rapidly to good lower bounds and visit new best-known solutions.

Model building for air-traffic controllers' workload regulation

Abstract In the supervision of industrial processes, complex situations appear that only a human operator (HO) is able to grasp. This complexity comes from the size of the process and from the diversity of factors to master. Designing help functions for the supervising operator is one way to improve the mastery of its complexity. This complexity must be grasped by the designer of help functions. But in this context, the HO introduces an additional difficulty. In order to master all the difficulties several points of view from various disciplines and techniques are necessary.

New hybrid matheuristics for solving the multidimensional knapsack problem

In this paper we propose new hybrid methods for solving the multidimensional knapsack problem. They can be viewed as matheuristics that combine mathematical programming with the variable neighbourhood decomposition search heuristic. In each iteration a relaxation of the problem is solved to guide the generation of the neighbourhoods. Then the problem is enriched with a pseudo-cut to produce a sequence of not only lower, but also upper bounds of the problem, so that integrality gap is reduced. The results obtained on two sets of the large scale multidimensional knapsack problem instances are comparable with the current state-of-the-art heuristics. Moreover, a few best known results are reported for some large, long-studied instances.

Hybrid Variable Neighbourhood Decomposition Search for 0-1 Mixed Integer Programming Problem

Abstract In this paper we propose new hybrid heuristics for the 0-1 mixed integer programming problem, based on the variable neighbourhood decomposition search principle and on exploiting information obtained from a series of relaxations. In the case of a maximization problem, we add iteratively pseudo-cuts to the problem in order to produce a sequence of lower and upper bounds of the problem, so that integrality gap is reduced. We validate our approaches on the well-known 0-1 multidimensional knapsack problem, in which the general-purpose CPLEX MIP solver is used as a black box for solving subproblems generated during the search process. The results obtained with these methods are comparable with the current state-of-the-art heuristics on a set of large scale instances.

AMANDA V3: Toward a Common Workspace between Air Traffic Controllers

This paper presents the different tools developed in the LAMIH, in optics to assist air traffic controllers in their tasks, to decrease their workloads, and to enable them to support the ceaseless increase of the traffic. Common philosophy to all these tools is to preserve the controllers in the loop: we do not try to develop tools entirely automatic. The platform AMANDA V2 made it possible to set up and to evaluate a common workspace, which allows the two controllers of a sector to cooperate and to share the same representation of their traffic and conflicts. This space maintains common situation awareness. This tool was very appreciated by professional controllers and we now wish to extend this principle to the co-operation between two planning controllers of two adjacent sectors. It is what we present in this paper which begins with a presentation of the ATC then a point on the platforms of the laboratory and particularly AMANDA V2, to conclude with the objectives of AMANDA V3.

VNS based heuristic for solving the Unit Commitment problem

Unit commitment problem for thermal units consists of finding an optimal electricity production plan in a long time horizon. In this paper, we propose an hybrid approach which combines Variable Neighborhood Search metaheuristic and mathematical programming to solve this NP-Hard problem. For each period, the economic dispatch problem which can be formulated as a convex programming problem is solved by the Lambda iteration method. Extensive computational experiments are performed on well-known test instances from literature. The proposed method successfully solved both small and large scale problems and offers the best results for the problem compared to the well-known metaheuristics used for solving it.

A Mixed Integer Program for a Dynamic Task Allocation Problem

Abstract In this paper we propose a mixed integer programming model for a type of supervisory assistance which is the dynamic task allocation between man and machine. We study the behavior of this model when it is solved by Branch and Bound methods in a real context which is the air-traffic control.

TOWARD A COOPERATIVE ACTION-DRIVEN DECISION MODEL OF AN AIRPORT SECURITY PROCESS

This paper presents a prospective and conceptual approach based on an action-driven decision that can lead to build a future decision. Such a process is driven by an action facilitated by the human-machine cooperation principles. Decision-making and action-making are then proposed to develop a cooperative action-driven decision model. This model is applied to airport security and is compared to the present organization model in order to identify possible improvements. Copyright

Choice, sorting and ranking in aerial conflict management

Abstract In the Air Traffic control, many decisions must be taken, quickly. Due to the increase of traffic, these decisions are more and more numerous. It is possible to propose some assistance tools to air traffic controllers in order to help them to make decisions. For that purpose we need to understand how the controllers make these decisions. This paper proposes a knowledge acquisition approach composed of three steps: an analysis of the decision-making process, a multiple criteria methodology, and interviews in order to obtain information, and to develop models. The last part of this paper presents the results we expect to obtain with appropriate interviews and analyse.