Research On The Problem Of Multiple Objective Optimization Of Airport Gate Assignment With Push-out Conflict Avoidance

The main purpose of the airport gate assignment problem(AGAP) is to assign aircraft to available gates so that the passengers can catch their destinations which include their connection flights, and then airport ground operations can keep in order. The problem is constrained by the density of airlines, the type of aircraft, the time between aircraft arrive and leave the gate, the walking time of the passengers and the distances concerning passengers and baggage. Poor assignment decisions may result in delays, congestions, even safety problems.The existing multi-objective optimization problems of AGAP have paid no attention to push-out conflict avoidance. The conflicts take place when there is a too short interval between the taxi-in or push-out times of two airplanes which are assigned to neighbor gates. Most of the times, safety ensuring is being paid more attention to than efficiency. However, push-out conflicts may happen rapidly, which cause a potential threaten to the safety.Based on analyzing the research both domestic and abroad, the research takes the lead in make multi-objective optimization problems of AGAP include push-out conflict avoidance. And two AGAP mathematical models that each includes three objective functions are established in this paper. The first is to minimize the total walking time of passengers. The second is to minimize the dispersion of idle time periods for aircraft-gate assignment. The third is to maximize the usage of large gates to large airplanes. The most important part is that the push-out conflict avoidance considered as a safety restriction in this paper, which can achieve the push-out conflict avoidance without extra manual work. The two models are established about the gate resources unconstrained and constrained, and the latter includes a fourth objective function than is to minimize the number of ungated flights. Then the models are solved by genetic algorithm programmed with MATLAB and show the validity of improving both safety and efficiency by comparing our approach to that one without safety restrict. The research also make a contribution for the avoidances of other similar conflicts...