Research And Simulation On Multi-tasks Scheduling Strategy Of Air Cargo Terminals Monitoring System

With the rapid development of logistics and information construction, as one of the important taches of aviation logistics, the air cargo terminal has also been accelerating the construction of informnatization. Advanced automation equipments have been introduced constantly. At the same time, the air cargo terminal monitoring system has been developed to realize full automation management. The monitoring system integrates the functions of monitoring, control, scheduling and management, featuring the characteristics of high real-time, centralized scheduling and resources distributed in unison. The monitoring system, a new form of control and management, has been playing an increasingly important role.in air cargo terminal. The overall requirement of air cargo terminal is faster speed, and multi-task scheduling is one of the important ways to save operation time. Therefore, it has great significance to study multi-task scheduling.At the peak of freight transport, multiple tasks exist in the task queue of the montoring system. When execution sequence is different, the time that spent on executing these tasks is different. When allocated resources for these tasks are different, the time and the stability of the shelves are also different. Based on the design research and practial application of a certain airport cargo terminal monitoring system, this paper put forward the subject that research and simulation on multi-task scheduling strategy of air cargo terminal's monitoring system. Two typical scheduling problems were analysed deeply, the bulk region' multiple temporaiy outbound tasks and the ULD region' multiple inbound tasks. Mathematical models were built respectively and solved by genetic algorithm. At last, it was proved through the simulation of MATLAB.The main contents of this paper are as followed:(1) Firstly, the paper described the air cargo terminal in general, and introduced the common equipments and their work modes in detail, then made a deep analysis of various kinds of tasks principles and work flow in the online mode. This paper emphatically analysed characteristics of multi-task scheduling in the air cargo terminal monitoring system. According to the essential feature of multi-task scheduling, genetic algorithm is applied in the paper.(2) For the scheduling problem of the bulk cargo area' multiple temporary outbound tasks, mathematical model was built aim for minimum execution time and solved by genetic algorithms with the reversion and evolution operator. In the paper, the ecoding machanism, option, crossover and mutation were introduced in detail, including design procedure of evolution and reversion operator. At last, it was testified through the simulation of MATLAB. The experimental data showed the algorithm with the reversion and evolution operator was available for the scheduling problem of the bulk cargo area'multiple temporary outbound tasks. Besides, this algorithm can reduce the total execution time and is superior to basic genetic algorithms in searching the global optimum solution.(3) It made a further analysis and research upon operational conditions and the process of processing double plate. Translated the freight lot allocation problem into the constraint conditions of multiobjective optimization problem and set up a mathematical model. The model was solved by genetic algorithm combined with Pare to solution aggregate and niche technique. The genetic algorithm adopted multi-stage parameters cascade coding method, effectively considering double plate restricted condition and adopted the competition mechanism based on niching technique. The corresponding eliminated mechanism was designed in Pareto solution aggregate to ensure evenly distributed. The experimental data obtained by the simulation of MATLAB showed this genetic algorithm can solve the optimal Pareto solution aggregate of the ULD region' multiple inbound tasks freight lot allocation problem. This kind of scheduling strategy can shorten the total execution time, making the layout of the shelves more reasonable. And due to the optimal Pareto solution aggregate with multiple solutions, the operator can select different scheduling scheme according to different job purpose.