2021 Vol. 39, No. 3

2021, 39(3) doi: 10.3963/j.issn.1674-4861.2021.03.020
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2021, 39(3) doi: 10.3963/j.issn.1674-4861.2021.03.019
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Overview
A Review on the Methods of Detecting Workload of Seafarers
YANG Liu, HE Meng, LIU Qing
2021, 39(3): 1-7, 16. doi: 10.3963/j.jssn.1674-4861.2021.03.001
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Maritime safety is a research hotspot in waterway transportation.The driving behaviors and options of seafarers directly affect maritime safety and are related to workload.Therefore, studying workload detection of seafarers is of great significance to prevent maritime accidents caused by human factors.First, individual factors, driving tasks, driving environment, and ship working conditions are the main factors on seafarers'workload.Then, some methods of seafarer workload detection are summarized from subjective evaluation method, task performance measurement method, and physiological data-detection method.There are some limitations in the research process of task performance measurement methods.Subjective evaluation and physiological data-detection methods are mainstream because of easy access to data and less interference to driving.Finally, it points out the development trends of seafarer workload detection: quantitative research on workload, construction of the comprehensive evaluation model of workload, the influence of multiple factors on workload, and construction of monitoring system to detecting workload of seafarers.
A Visualized Review of Research Progress in Aviation Safety
YANG Xiaoyong, ZHANG Hui, LIU Shangyu, ZHANG Heng
2021, 39(3): 8-16. doi: 10.3963/j.jssn.1674-4861.2021.03.002
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The work analyzes 1 340 related references collected from 2001 to 2020 in the web of science(WOS)core collection to explore the focused issues and trends in studies of international aviation safety.Bibliometric and visual analysis software CiteSpace and VOSviewer are used to investigate their spatial and temporal distribution, core author, co-citation network, and keyword clustering.The results are as follows: ①The publishing number of papers in international aviation security presents a fluctuating trend in a rapid growth stage after 2014.China ranks second but has not found a clear core authors group.②9/11 terrorist attack has accelerated the research on aviation security, especially in airport security screening.Other research focuses include fuzzy inference, aviation security, safety management, risk analysis, risk assessment, airport surface safety, and stochastic systems.③The research directions mainly focus on three aspects: the safety behavior of aviation personnel, the development of the airport security check system and aviation facilities, and the progress of safety management level.The future trend is the application of big data and artificial intelligence to the facilities of aviation safety.
Transportation Safety
Impacts of Major Epidemic on Passengers' Dependence on Public Transport
HU Song, WENG Jiancheng, LIN Pengfei, ZHOU Wei, JING Yunqi
2021, 39(3): 17-24. doi: 10.3963/j.jssn.1674-4861.2021.03.003
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Exploring the impacts of major epidemics on passengers' behaviors and dependence on public transportation can improve the quality of public transportation(PT)services and the balance between supply and demand.Based on the prospect theory and the theory of planned behavior(TPB), the work proposes the SP/RP travel survey scheme in the period of a major epidemic.Three indicators are selected from the dimension of travel behaviors, and a k-means algorithm is used to identify the PT passenger categories.The internal and external impact indicators of PT dependence are screened from seven levels.Then, a structural equation model is utilized to construct the model of major-epidemic impacts on passengers' PT dependence.The results show that the latent variables of individual attributes, travel environment, and travel characteristics indirectly affect passengers' PT dependence by changing individual psychological factors, which reflects the joint effect of subjective and objective factors on passengers' PT dependence.The positive intensity of travel intention on PT dependence under a major epidemic is 0.36, which is lower than that of 0.51 under normal conditions.The positive effect of the travel environment is strong, while the effect of individual attributes is relatively low and negatively correlated with PT attitude and subjective norms.Besides, bicycle availability, route risk, and travel intensity hardly affect passengers' PT dependence.The acquaintance of prevention and control policies, subjective normative variables, and travel preference on PT have significant effects, reflecting that the social promotion effect and the fuzzy effect of consumer psychology are more obvious in the PT market in the major epidemic period.
Influencing Factors of Electrical Bikes'Risky Riding Behaviors Based on Reinforcement Sensitivity Theory
TANG Tianpei, CHEN Feng, GUO Yuntao, ZHU Senlai
2021, 39(3): 25-32. doi: 10.3963/j.jssn.1674-4861.2021.03.004
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From a traffic management perspective towards the reward and punishment strategies, the work studies the influence mechanisms of the reward and punishment responses of electric bike riders on their risky riding behaviors.A psychological cognitive model for risky riding behaviors is developed based on the revised reinforcement sensitivity.Perceived risk and risky riding intention are incorporated into the proposed framework, accounting for the potential impacts of gender, age, and riding frequency.The structural equation model is used to identify key psychological factors influencing risky riding behaviors with the self-reported survey data of 402 valid samples.The model-estimation results are as follows: ①The revised psychological cognitive model fits the data well(χ2/df=1.343, and RMSEA=0.029)and can explain 48%of the variance in risky riding behaviors.②Punishment sensitivity and reward sensitivity significantly affect risky riding behaviors, with the stronger influence of the latter.③Perceived risk and risky riding intention statistically affect risky riding behaviors.④Gender directly affects punishment sensitivity and rewardsensitivity and indirectly affects the risky riding behaviors via both variables.The influence of age and riding frequency on each variable is not significant.
Rapid Generation and Dynamic Optimization of Traffic Emergency Plans for Large-scale Events
SHEN Ling, LU Jian, WANG Chengchen
2021, 39(3): 33-40. doi: 10.3963/j.jssn.1674-4861.2021.03.005
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The generation and dynamic optimization technology of traffic-emergency plans under large-scale emergencies rely on experience, and the manual plan lacks targeted and quantitative emergency measures.The feature attributes of emergencies are extracted to quickly generate the optimal matching plan.The initial plan is quickly generated based on case-based reasoning(CBR)and naive Bayesian classification and selected according to the posterior probability obtained by the Bayesian classification algorithm.The knowledge base and rule base of traffic emergency plans are established based on rule-based reasoning(RBR), and the content of the plan is modified by forwarding reasoning.The evaluation-index system of emergency-response capability and emergency severity is established based on the fuzzy analytic hierarchy process(FAHP).Taking Beijing 2022 Winter Olympic Games as the case background, the method can quickly generate the optimal matching plan and realize dynamic adjustment and improvement.
A Contrastive Analysis of Survivability of Urban Rail Network Based on Complex Network Theory
ZHAO Ruilin, MOU Haibo, XIAO Ding, YANG Jingfeng
2021, 39(3): 41-49. doi: 10.3963/j.jssn.1674-4861.2021.03.006
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The metro networks of 10 typical cities in China are selected to analyze the resilience of different metro networks to emergencies.The complex network theory is used to analyze the resilience of networks under simulated attacks.Pajek software is used to construct an abstract road network of topological space Space-L.Quantitative evaluation indicators are set to systematically analyze the survivability of the network under random attacks and deliberate attacks of accumulated nodes.The improved network efficiency formula is used to analyze the influence of each node on the network under the single-node deliberate attack.The results show that the metro network is a scale-free network.Based on node degree, network efficiency, and the maximum connection sub-grap, the proportions of failed sites in the two networks reach 10.44%and 11.09%, 17.99%and 18.39%, and 13.27%and 12.92%under random attacks, and the net crashes.Under cumulative-node deliberate attacks, the proportions of failed sites in the two networks reach 5.22%and 5.17%, 4.3%and 3.19%, and 4.23%and 2.43%, and the net crashes.Compared with the failure node at the intersection of divergent lines, the node at the apex of the triangle or the mesh structure is more invulnerable to the network.
Transportation Information Engineering and Control
A Metaheuristic Algorithm for Multi-objective Transit Bus and Driver Scheduling Problems
KONG Yunfeng
2021, 39(3): 50-59. doi: 10.3963/j.jssn.1674-4861.2021.03.007
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This article introduces a metaheuristic algorithm for multi-objective transit bus and driver scheduling problems, such as fuel or electronic vehicles, single route/multiple routes, and driving the same bus on the same day in most transit companies in China.The work aims to minimize the fixed bus cost, the bus travel cost, the fixed driver cost, and the allowance for drivers and to satisfy various operational rules on vehicles and drivers.The algorithm starts from an initial solution and iteratively improves the solution by local search and perturbation.It is also enhanced by two search strategies such as population-based search and variable neighborhood decent search.The performance of the proposed algorithm is tested on 62 single-route instances and 11 multi-route instances.There are three important findings for transit operations in China from the experimentation.Electronic vehicles may replace fuel buses by increasing 0.8% and 1.6% vehicles for single-route and multi-route instances, respectively.Compared with single-route scheduling, multi-route scheduling has the potentials to reduce 4.6% of vehicles and 2.4% of drivers.If the drivers are allowed to drive different buses in their daily works, the number of vehicles required can be reduced significantly, especially for the single-route instances.The general-purpose metaheuristic algorithm in the work is essential for developing intelligent public transit systems in China.
Multi-Objective Optimization for Coordinated Control of Double-cycling Arterial Signals Considering Dynamic Vehicle Speeds
ZHANG Jingsi, LI Zhenlong, XING Guanyang
2021, 39(3): 60-67. doi: 10.3963/j.jssn.1674-4861.2021.03.008
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Arterial coordination control usually aims at maximizing the traffic efficiency in the main direction, which leads to a large delay in the cross street of some minor intersections.Based on the cooperative vehicle infrastructure, the work studies the multi-objective optimization method of double-cycling arterials under speed guidance.Aiming at the saturated and unsaturated traffic flow at the upstream intersection, a dynamic speed guidance model considering queue dissipation and offset is proposed.Furthermore, a double-cycling arterials multi-objective optimization model is constructed taking the average delay time, the average number of stops, the capacity of arterials, and the average delay of the double-cycling intersection as the comprehensive optimization objectives.Then, the genetic algorithm is used to solve the model to obtain the optimized coordinated signal-timing scheme.Based on the COM interface, the cooperative vehicle infrastructure environment is built using Python and Vissim software, and the model is simulated by taking three intersections of Guanganmen Inner Street in Beijing as a case study.The results of this model are compared with those of the original scheme and the multi-objective optimization model of the double-cycling artery without speed guidance.Compared with the original scheme and the multi-objective optimization model without speed guidance, the average delay of arterial is reduced by 19.6% and 8.3%; the capacity increased by 5.6% and 8.4%; the average number of stops is reduced by 11.2% and 24.2%; the average delay of the cross street of the double-cycling intersection re-duced by 33.9% and 5.8%, respectively.The results show that this model combines speed guidance with multi-objective optimization to achieve dynamic speed guidance, with the increased traffic efficiency of the double-cycling artery, the reduced delay of a cross street at a double-cycling intersection, and the mutual optimization of the artery and double-cycling intersection.
An Estimation Method of Traffic Flow State Based on Matching of Temporal-spatial Feature Sequences
CHEN Jialiang, HU Zhaozheng, LI Fei
2021, 39(3): 68-76, 120. doi: 10.3963/j.jssn.1674-4861.2021.03.009
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An estimation model of the traffic flow state based on matching of temporal-spatial feature sequences is studied to better estimate the traffic flow state for the road section without a traffic flow detector and improve the estimation accuracy.The model firstly uses the calculation method of the traffic-operation index to preset the traffic-flow state of the urban-road section with traffic flow data.Various factors affecting the operating conditions of urban roads are analyzed, with the introduction of the characteristics of time and space multi-dimensional parameters such as traffic flow parameters, road parameters, and road network topology parameters.The temporal and spatial characteristics of traffic flow form by extracting 3 dimensions, 8 features, and 1 additional dimension, thus constructing the DNA feature sequence of urban-road traffic flow.After normalizing the value of each feature, the WH-KNN matching method is used to obtain the traffic-flow state closest to the road section to be estimated in the whole road network.The experiment selects the data of one week in road sections 10468, 10483, and 8816 of Wuhan Zhonghuan Expressway.Assuming that the road section data is missing, the traffic flow state is estimated by the method described above, and the estimated results are compared with the original data results.The results shows that the model can obtain the traffic flow state of the road section without detection data as well as maintain the accuracy rate of the state estimation result above 88%. The misjudgment is within a performance-index level.
An Optimization Method of Vehicle Routing Considering Vehicle Restrictions and Two-dimensional Loading Constraints
XU Xiangbin, REN Chenhao
2021, 39(3): 77-84. doi: 10.3963/j.jssn.1674-4861.2021.03.010
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Considering vehicle restrictions in some urban roads and the vehicle-loading constraints such as Last-In-First-Out (LIFO) unloading rule, vehicle restrictions and two-dimensional loading constraints are added to the split routing of delivery vehicles in real distributions. A 2LVR-SDVRP mathematical model is constructed to minimize the total distribution costs consisting of the fixed cost and transportation cost. A heuristic algorithm is proposed to solve the model. Wherein, SA determines distribution routing, and BLF examines the vehicle-loading constraints when the current optimal solution routes are determined, which reduces the time of frequently calling the BLF algorithm. The practicability of the model and the algorithm is verified by a case study. Besides, the proposed algorithm can solve a better distribution scheme within a reasonable time range, with the fluctuation of optimal solutions no more than 0.8%. The total distribution costs of dual-vehicle distribution are from 15.17% to 31.27% less than those of single-vehicle under vehicle restrictions.
A Forecast of Short-term Passenger Flow of Rail Transit Based on IGWO-BP Algorithm
ZHANG Yiming, CHEN Mingming, SHI Lei, KANG Ronggui
2021, 39(3): 85-92. doi: 10.3963/j.jssn.1674-4861.2021.03.011
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Short-term passenger flow of rail transit has the characteristics of randomness and nonlinearity. An IGWO-BP algorithm is developed to forecast short-term passenger flow based on improved grey wolf optimization (IGWO) and BP neural network to improve the accuracy of predicting the short-term passenger flow of rail transit. The correlation coefficients of different time series of the rail-transit passenger flow are calculated to determine the input and output modes of the BP neural network. The cosine thought and dynamic weighting strategy are used to improve the orginal grey wolf optimization algorithm, thus enhancing the algorithm's global search and optimization. The IGWO algorithm is used to optimize the initial weights and thresholds of the BP neural network, which can improve the accuracy of predicting the short-term passenger flow. The work predicts the short-term passenger flow at the 15-min time granularity of the LONGSHOUYUAN Station of Xi'an Rail Transit Line 2 on Wednesday morning peak. The predicting results of the IGWO-BP algorithm are compared with those of the other five models (KF, GM, SVM, BPNN, and GWO-BP). For the IGWO-BP algorithm, the RMSE is 89.65, and the MAPE is 1.16%. The results show that the IGWO-BP algorithm has optimal accuracy and stability.
Transportation Planning and Management
A Quantitative Analysis on Urban Bus Emissions and Energy Consumptions under Different Road Speeds and Dwell Time
HUANG Wenfeng, YANG Pengshi, DING Hui, ZHAO Yongming, ZHONG Hui, LIU Yonghong
2021, 39(3): 93-102. doi: 10.3963/j.jssn.1674-4861.2021.03.012
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A model for estimating gas or electric bus operating conditions and emissions (or energy consumptions) is developed to quantify urban bus emissions and energy consumptions under different road speeds and dwell time at different locations. This model is developed by more than 750 thousand GPS records of 5 bus lines and a large amount of floating vehicle data. The result shows that in road areas, the road speed of mixed traffic flow has a greater impact on bus emission and energy consumption than dwell time at bus stops. As the road speed increases by 5 km/h, the relativebus speed increases by 0.17, and the relative emission factor and relative energy consumption factor decrease by 0.11 and 0.06, respectively. In the bus stop area, the dwell time at the bus stop has a greater impact on bus emissions and energy consumptions than the speed on the road.As the dwell time decreases by 15 seconds; the relative bus speed increases by 0.11; the relative emission factor and relative energy consumption factor both decrease by 0.06. Increasing the speed on the road at different locations does not always significantly reduce bus emissions and energy consumptions. Thus, cooperative control of bus operation efficiency and emissions (or energy consumptions) should be carried out in the comprehensive traffic system.
A Programming Model for the Flexible Multi-depot Heterogeneous Dial-a-ride Problems
CHEN Kejia, FANG Yunfei, LUO Jiayi
2021, 39(3): 103-110. doi: 10.3963/j.jssn.1674-4861.2021.03.013
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A mathematical model of mixed-integer non-linear programming is firstly constructed to solve a new dial-a-ride problem(DARP), the multi-depot heterogeneous dial-a-ride problem with flexible depots(MDHDARP-FD), as well as minimize the total driving cost.Due to the complexity of the proposed model, some strategies of linearizing constraints, aggregating variables, and strengthening inequalities are performed to reformulate the non-linear model.During linearizing constraints, non-linear constraints are rewritten as equivalent linear constraints.Aggregating variables, decision variables with the same properties, are aggregated to reduce the number of variables, with strengthened inequalities and valid inequalities introduced to strengthen the model.As a result, a new linear programming model with a small solution space is obtained and can be tractable.Then the dial-a-ride problem is simulated by combining different vehicles and passengers'demands.Simulation results show that compared with the traditional dial-a-ride problems, the model can obtain a group of optimal vehicle routes respecting the complex constraints and reduce the total driving cost, vehicle driving time, and solution time.The total driving cost can be reduced by 1.51%to 6.69%for different DARPs on an average, verifying that the total driving cost of dial-a-ride problems can be reduced with the introduced flexible depots.
Travel Decision-making Behaviors of Urban Electric Bicycle Users Considering Psychological Latent Variables
HU Cheng, HUANG Helai, LI Xintong, HAN Chunyang, JIANG Qianshan, YANG Qiushi
2021, 39(3): 111-120. doi: 10.3963/j.jssn.1674-4861.2021.03.014
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This paper aims to explore electric bicycle users'behavioral responses to different management policies of electric bicycles issued in 2018.A survey is conducted to collect socio-demographic characteristics, travel habits, psychological characteristics of electric bicycle users, and their decision-making against different policies.A multiple indicators and multiple causes model is constructed considering several latent variables such as policy acceptability to obtain the fitted value of the latent variables.Then a hybrid choice model taking the latent variables as explanatory variables is applied to analyze the impacts of social-demographic related variables, travel habit variables, and psychological latent variables on the travel decision of electric bicycle users.The results show that: ①The psychological characteristics of electric bicycle users significantly affect their travel decision-making, and travelers with higher policy acceptability tend to adopt positive behaviors.②Economic factors prompt the travelers to continue to use illegal electric bicycles or violate the policy.③Subsidies for scraping illegal electric bicycles can neutralize the impact ofeconomic factors on decision-making and can promote low-income families to purchase electric bicycles fitting the standard.④The implementation of the policy will promote the mode switching from electric-bicycle traffic to car traffic.
A Comprehensive Evaluation Method for Coordinating Resource Allocations and Passenger Flow of Bus Lines
MA Jiaxin, CHEN Xumei, KE Jingyu, PENG Fei
2021, 39(3): 121-127, 135. doi: 10.3963/j.jssn.1674-4861.2021.03.015
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Due to the imbalanced and inadequate resource allocations of bus lines, the quantitative coordination evaluation of the resource allocations and passenger flow of bus lines are essential for the optimized layout of the urban public transport network.The indicator system is developed by considering the characteristics of the coordination between the resource allocations and passenger flow.Because of the disadvantages of the traditional DEA method, such as the groundless selection of indicators, the subjective determination of their influence effects, and the difficulty in distinguishing effective decision-making units, the structural equation model is introduced as a basis for selecting effective indicators and identifying the rank of the influencing effects.Further, the differentiated coordination ranking is obtained based on the improved DEA model where the ideal point is introduced.Therefore, the work proposes a comprehensive evaluation method of the coordination between the resource allocations and passenger flow conditions.Finally, a case study is conducted with data from 65 bus lines in Haidian District, Beijing.The results show that the indicator of the average stop spacing has the most significant impact on the coordination of resource allocations and passenger flow, with an effect of 0.901.The five bus lines that are difficult to rank with the traditional DEA method are distinguished based on the proposed method.Also, the evaluation results consistent with the design and operation of bus lines show the good application of the proposed model.
A Quantitative Analysis on Repeatability of Residents'Bus Trip Chain and Travel Regularity
CUI Hongjun, SUN Wanru, ZHAO Rui, ZHU Minqing, LI Xia
2021, 39(3): 128-135. doi: 10.3963/j.jssn.1674-4861.2021.03.016
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As a hub system of urban transportation, public transportation carries a large number of residents'travel.The IC card data collected by the automatic data collection system contains a large number of passenger-travel information, which can be analyzed to optimize the public transport service.The information entropy and entropy rate are introduced to quantify the repeatability of the trip chain of public transport, with the method of analyzing the law of public transport travel based on the quantitative index studied.The trip chain of passengers is transformed into a discrete travel sequence through the state calibration of the travel place.Information entropy and the entropy rate are used to quantitatively analyze the travel sequence, thus obtaining the relationship between travel repeatability and quantitative index.In other words, the higher the information entropy of the travel sequence, the lower the entropy rate, the higher the passengers'travel repeatability, and the stronger the travel rule.Based on the repeatability of quantitative processing, the work takes the travel data of smart card passengers in Shijiazhuang as a case study to analyze the travel rules of bus passengers from group and individual.The results show that the quantification index of trip-chain repeatability can intuitively judge the strength of travel rules.When the information entropy is higher than the sample mean(2.53 bits)and the entropy rate is lower than the sample mean(1.13 bits/event)with the unobvious travel rules of passengers, the potential travel rules of passengers can be mined through further analysis.
An Evaluation Method for Bicycle Sharing Satisfaction Based on a Bivariate Ordered Probit Model
XU Jiahong, ZHOU Jibiao, MA Changxi, WAN Yan, SHEN Ying
2021, 39(3): 136-141, 151. doi: 10.3963/j.jssn.1674-4861.2021.03.017
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As an integral part of the urban green transportation system, bicycle sharing is an important way to serve the public for short-distance travel and public transport interchange, playing an active role in solving the"last mile"of urban transportation.A valid sample of 1 212 bicycle-sharing users in Ningbo is collected using questionnaires and field surveys to assess the satisfaction of bicycle-sharing services.Also, a bivariate-ordered-probit(BOP)model is constructed using statistical methods to analyze the factors influencing bicycle sharing satisfaction and calculate the marginal effects of significant influencing factors.The BOP model is used to quantify the utility of the factors influencing bicycle sharing satisfaction and usage.The results show that it can quantify the factors influencing the frequency and satisfaction of bicycle sharing.Gender, age, education, household ownership, usual travel mode, and trip distance are statistically significant factors influencing satisfaction with bicycle sharing services in the city.From user needs and service perceptions, the main problems of the existing service and the aspects that need to be optimized are understood to improve the quality of bike-sharing service and users'travel experience.
A Method for Hierarchical Planning of Ground Access Network of Airports Based on Accessibility
BAO Danwen, CHENG Hao, ZHU Ting, TIAN Shijia, ZHANG Tianxuan
2021, 39(3): 142-151. doi: 10.3963/j.jssn.1674-4861.2021.03.018
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The planning of ground access network of airports affects the efficiency and experience of passengers.The traditional road-network planning method is used to propose a hierarchical planning of the ground access network of airports based on accessibility and different characteristics to improve travel and passengers'experience.The ground access network is divided into the highway and branch layers for their different characteristics and specific definitions.For the highway layer, the optimization aims at the weighted average travel time of passengers; for the brunch layer, the optimization aims at maximum accessibility.Meanwhile, a simulated annealing algorithm is used to solve the problem.The ground access network of Beijing Daxing International Airport is taken as a case study to verify the planning method, and the road planning for the future in Beijing is compared.The results show that the weighted average travel time of passengers at the highway layer is reduced by 7.1%, and the accessibility of the branch layer increases by 7.0%, which reflects the feasibility of this method.