Construction And Application Research Of 3D Visible Spectrum Database Of Urban Road Traffic Status

Since the 21st century,with the accelerating progress of urbanization and the rapid development of national economy,the number of urban motor vehicles surged every year,the contradiction between supply and demand of urban road traffic has become increasingly prominent,and the congested traffic problems have brought a serious impact on the urban road traffic system Safety and efficiency pose a huge risk.The improvement of urban road monitoring equipment,the continuous improvement of vehicle location system and the wide spread of hand-held mobile devices make more and more traffic data containing geographical location and time information stored.When the classic data visualization charts such as histogram and line chart are in response to the challenge of big data,Often can not show satisfactory results,the huge amount of data urgently need a new,efficient visualization of its analysis.So as to better mine the massive spatial and temporal traffic data reflected behind Traffic phenomenon,put forward an efficient and reasonable means of data analysis as an effective way to solve the problem of traffic jams.This paper takes the urban traffic system as the research object,uses GPS floating car data,and uses visualization techniques to explore and propose a three-dimensional viewable spectral library construction method based on time,space and traffic operation state,aiming at visualizing the city from a macro perspective.The road network’s traffic evolution process under different typical traffic conditions,and extracted traffic congestion duration parameters from the map library,studied the influence of different factors on the evolution of urban traffic congestion and the influence and direction of various factors on congestion.It provides decision-making basis and technical support for road managers to accurately grasp the urban traffic operation rules,achieve effective traffic guidance and traffic control.The main research contents and conclusions of this article are as follows:(1)Eextraction of traffic parameters and traffic classification.The method of estimating the average travel speed of road sections is expounded,and the average travel speed of road sections is calculated by using the floating car data.The traffic status of road sections is classified according to the average travel speed of road sections and the grade of road sections.(2)To explore the construction of the three dimensional visible spectrum database.By referring to a large amount of documents and drawing on the expression of trajectory wall,the ArcGIS software platform is used to build the three dimensional visible spectrum database of traffic status.Firstly,a traffic state space-time database containing static road network space information and traffic parameter time information is set up,and the space-time data is symbolized and visualized to realize the spatiotemporal visualization of the traffic state space-time data in different environments.With ArcGIS analysis function,traffic parameters such as congestion duration are extracted to analyze traffic characteristics.(3)Analysis of Distribution Characteristics of Congestion Duration Based on Atlas and Its Influencing Factors.With the aid of the map library,the congested duration parameters of typical expressways in mountainous cities in different traffic environments are extracted.The non-parametric method of survival analysis was used to analyze the regularity of the congestion duration of typical expressways under different influencing factors,and the Cox proportional hazards model was constructed to analyze the influence degree between the duration of congestion and its influencing factors.The results showed that:Among the four possible influencing factors of conditions,traffic conditions,time factors,and road conditions,except for the impact of bus stations on the duration of congestion,bridges,late peaks,early peaks,workdays,and ramps are the main factors contributing to congestion,resulting in congestion.The consecutive probabilities were 50.2%,18.1%,14.9%,13.9%,and 11.6%.The four-lane,rainy days,and low speed were the secondary factors for the continuation of congestion.The probability of continuation of the congestion increased by 9.4%,8.3%,and 2.7%in turn.