Driver And Pedestrian Smartphone Ise Behavior At Signalized Intersections:Impact On Traffic Efficiency And Safety

Mobile Internet applications,such as smartphones,have been widely popularized in China.The smartphones' GPS localization,map navigation functions,etcetera,have brought great convenience to traffic travel.However,the application of smartphones also has a tremendous impact on the operation of the traffic systems.This thesis mainly studies the influence of drivers and pedestrians'smartphone use on traffic efficiency and traffic safety at signalized intersections.Selecting typical signalized intersections in Hangzhou as the research object,the thesis carries out the research from two perspectives:the impact of driver's mobile phone use at red traffic signals on the start-up loss time,headway and saturation flow of the intersection,and the pedestrian's mobile phone use while crossing and its safety analysis.The main contents of this thesis are as follows:(1)Investigation of driver mobile phone use behavior during the red traffic signals.This thesis has designed two types of survey schemes:questionnaire survey and naturalistic survey.Questionnaires were conducted in the form of online questionnaires,including 27 questions,which related to the use of mobile devices during the waiting period of motor vehicles at a red traffic signal.The number of valid samples of questionnaires was 151.At the same time,the video data of five signalized intersections during the waiting period of vehicle red signals are acquired by video acquisition method,and the behavioral data samples of 2596 vehicles are acquired by video observation and manual judgment.Through these data,the mobile phone use behavior during vehicle red signals is analyzed and modeled.(2)Analysis of the influencing factors of driver's phone use behavior during the red traffic signals.According to the naturalistic(video-based)survey data,this thesis analyzed the important factors affecting drivers' use of mobile phones during the red signal period.A more robust and effective analysis method is proposed,which is the fusion analysis of non-dominated sorting genetic algorithm(NSGA-II)and logistic regression.The results reveal that the type of vehicle,the presence of passengers in the vehicle,the waiting time for red signal and the driver's age are the first four main factors affecting the use of mobile phones by drivers during the red phase of a traffic signal.(3)Analysis of the impact of mobile phone use on the operating efficiency of intersections.By analyzing the relationship between the operating behavior of the queued first three vehicles and the use of mobile phone during the red-period,the quantitative effects of using mobile phones on drivers' reaction time(start-up loss time),headway and saturated flow rate were compared respectively,and then the influence of mobile phone use on intersection operational efficiency was obtained.(4)Assessment performance indicators of pedestrian crossing behavior.This part mainly discusses the concept and measurement methods of basic performance indicators of pedestrian crossing,including pedestrian crossing distance,crossing time,stopping time,walking time,crossing speed,start-up time,start-crossing delay and so on.On this basis,the concept and measurement methods of pedestrian crossing safety performance indicators are proposed,including pedestrian Origin-Destination(OD)and trajectory difference,conflict avoidance rate and eye contact rate.(5)Analysis of the influence of mobile phone use on the safety of pedestrian crossing behavior.Four crosswalks at signalized intersections in the city of Hangzhou were investigated on the spot.Through data analysis,the effects of different types of mobile phone use and whether there is a central safety island on the safety of pedestrian crossing are studied.