Microscopic Theoretical Modeling Of Airplane Boarding Process And Boarding Strategy Optimization

The air transportation industries grow rapidly in recently years,at the same time they encounter with severe challenges,such as the international carbon emissions limits,oil price fluctuations,fiercely competition with other means of transportation,especially the high-speed railway system.Therefore,how to fully utilize the existing aviation resources and improve operational efficiency becomes an urgent problem for airlines.One of the most promising ways to get more profits is reducing the airplane turn time,which constitutes the time to unload an airplane after its arrival and to prepare it for departure again.A significant saving could be obtained by reducing the enplaning time,since it is the key part of an airplane's turn time.So,airlines have been exploring the fastest boarding strategy.This dissertation evaluates various boarding strategies from different perspectives,and proposes some optimized boarding strategies as well as management measures.The accomplishments of those works will ultimately provide scientific suggestions for the aviation planning and operation.The main line of this dissertation is designing of airplane boarding strategy,combined analytical method with simulation method,as well as the qualitative analysis and quantitative analysis.By utilizating system science,traffic engineering,computer science and other disciplines,we carry out a comprehensive research on boarding problem,such as modeling passenger flow dynamics,optimizing boarding strategy and investigating microscopic mechanism behind boarding process.The detailed contents of the research include:(1)Micro modeling of the passenger boarding process and strategy evaluation.The main pourpose of this section is to explore the characteristics of passenger flow dynamics,distinguish the main factors influencing the airplane boarding time,as well as their mutual relationships,and finally establish a passenger boarding simulation model based on cellular automata.Numerical simulations are carried out to investigate how the various factors affect the passenger boarding behaviors,and the formation and dissipation of jams in the boarding process.The efficiency of some typical boarding strategies is evaluated,as well as boarding time stability,sensitivity to the boarding conditions,such as luggage distributions and cabin occupancy rates.Simulation results indicate that the improved strategy i.e.,Steffen strategy,is time saving and much more stability compared with other traditional strategies like Back-to-front and Random.(2)Optimization and design of airplane boarding strategies.Two methods are separately proposed in this paper to improve the boarding efficiency.For the first strategy,we utilize the simulated annealing algorithm to obtain the minimum boarding time under a deterministic boarding model.The evolution of finding minimum boarding time provides some inspirations to find two fast boarding sequences.Furthermore,considering the aisle interferences arisd from storing luggage is the main reason for the time delay,we finally propose a new optimizated boarding strategy with considering the distribution of luggage in the cabin.For the second strategy,we take both the enplaning and deplaning processes into consideration,since both of them are the main factors contribute for the airplane turn time.We propose a symmetrical design of deplaning strategies to match three typical grouped enplaning strategies,in which the groups are organized in a 'last in first out' manner.The efficiency,stability,fairness,maneuverability and other aspects of the proposed strategy are tested by using the proposed cellular automata model.Simulation results show that the first proposed strategy could largely reduce the boarding time;the second proposed strategy not only reduces the total time of enplaning and deplaning but also guarantees fairness between different enplaning groups.(3)Seat preference and free boarding modeling.Budget airlines adopt free boarding strategy when conducting passengers to board the airplane in which passengers are not offered any preassigned seats and they choose their favourite seats freely.A simulation framework based on cellular automaton is developed to mimic the dynamics of passenger flow in the free boarding process.In the model,each seat in the cabin is assigned a positive value to character how desirable it appears to the overall passengers.A logit-based discrete choice principle is applied to formulate the seat choice behaviors of passengers.The influence of the sensitivity parameters on the mean boarding time is discussed in order to identify the different classes of behaviour exhibited by the model.Besides,two grouped strategies in a manner of free style are proposed,and quantitative comparisons are made with those that involve assigned seats.(4)Analysis of micro mechanism behind boarding time delay based on particle hopping model.Aiming at to further analyze the nonlinear relationships between the various factors,the airplane boarding process is viewed as a simple particle transmission system in this section.Distinguished by the particle speed hypothesis two models are considered.The first model ignores particle speed when boarding,namely the particles' advancing time along the aisle is neglected.The discussion mainly focus on analyzing how the scaling behavior of mean boarding depends on the dimensions of cabin seat layout,sequence order and relative factor such as congestion coefficient.The second model takes particle's velocity into consideration,in which particles are injected,moving along a one dimensional aisle,and finally removed at reserved sites.This model is able to describe the dynamic flow characteristics in the boarding process,such as the formation and dissipation of jams.Simulation results found three states in boarding process:free flow,jamming and maximum flow.(5)Design of an equivalent airline boarding experiment.Considering the difficulty of carrying out the boarding experiment in the real world,here we carried out equivalent airline boarding experiments based on the similarity principle,in which participants are organized to board a bus with 10 rows of four seats and a single aisle.We test seven strategies by evaluating their boarding time,time flunction and interval time of getting through the bus gate.Besides,two structured delighting strategies are also evaluated to test their abilities to reduce the delighting time.Moreover,we will discuss how the boarding process is affected by the passengers' seat preference in the free boarding strategy.Experimental test results confirm the high efficiency of the proposed Steffen-lug and CRBF strategies.Moreover,the experiment results also stress the importance of enplaning condition,for example the number of luggage passenger taking along,on selecting the enplaning or deplaning strategy.