Study on coordinated control of urban regional traffic system based on copula functionLi, LiHong; Xue, YuJun; Wang, WeiHang
doi: 10.1117/12.2627797pmid: N/A
Urban traffic is a complex system composed of multiple roads and intersections. The unimpeded road traffic directly affects the development of urban economy. The intersection is the pivot of urban road traffic and plays an important role in the management of the road traffic. Traffic at an intersection often is influenced by other intersections and is a result of a joint impact of them, there must be the relationship between an intersection and several other intersections. This relationship is difficult to express with determined mathematical formula due to the stochasticity of resident travel. However, the copula function can connect the distribution function of traffic flow at an intersection with the joint distribution function of traffic flow at several upstream intersections to establish a mathematical model and predict the traffic flow at this intersection. This traffic flow can be regarded as a traffic control parameter for the intersection, and can effectively improve the coordinated control in the region.This method has achieved good results with experimental validation.
Survey of expressway infrastructure based on vehicle-borne mobile mapping systemYuan, Qin; Yao, Lianbi; Xu, Zhengwen; Liu, Hao
doi: 10.1117/12.2627889pmid: N/A
Traffic infrastructure road property survey is the basic work of the intelligent management of traffic facilities, and traditional survey techniques have obvious shortcomings. Based on the investigation of a provincial expressway, this paper introduces the composition of the vehicle-borne mobile mapping system and the operation process and technical scheme of the highway infrastructure survey, and analyzes the acquisition results. It verifies the reliability and practicability of the vehicle-borne mobile measurement system in highway infrastructure surveys, and provides an efficient and accurate technical means for highway infrastructure surveys.
Urban rail transit route choice model using mobile phone user’s trajectory dataYu, Zijuan; Li, Qiang; Zhang, Xiaochun
doi: 10.1117/12.2627793pmid: N/A
Questionnaires are the traditional solution to obtain samples of urban rail passengers' route choice, but large-scale questionnaires are required to obtain a sufficient number of valid samples to calibrate a discrete choice model. The rail travel trajectory data of cell phone users provide a large amount of real travel data, which provides a new method to obtain rail route choice samples. Based on cell phone users' rail travel trajectory data, we propose a route choice model of rail passengers. First, this paper analyzes the issues and effects of the midway point loss of the track data of cell phone users, and explains the necessity of developing a discrete choice model. Second, this paper proposes a Logit model, and then describes the route travel time calculation method and the route choice dataset generation method, the latter of which fully considers the disadvantages and advantages of cell phone data. The model is calibrated and the result is evaluated based on the trajectory data of cell phone users in Shenzhen. The results show that the model proposed in this paper has high accuracy and can be utilized in actual rail passenger flow assignment.
Analysis of intercity highway traffic trip based on spatial autocorrelation model: an empirical study using mobile signaling dataLiu, Yi; Wu, Di; Ma, Jun; Wang, Yingping
doi: 10.1117/12.2627926pmid: N/A
Intercity transportation in urban agglomerations has the characteristics of large travel scale, diversified travel modes, diversified travel purposes, unbalanced temporal and spatial distribution and so on. Based on the mobile signaling data, this paper calculates the intercity travel volume and external traffic travel volume of the Beijing-Tianjin-Hebei urban agglomeration through data cleaning, processing, fusion and mining. Using the spatial autocorrelation analysis method, the spatial effect of intercity highway traffic travel is analyzed. The results indicate that the intercity highway travel volume of adjacent cities shows a significant positive correlation, and intercity highway travel is positively correlated with population, economic development level, urbanization development level and residents' income level.
A HIL platform for evaluating OBU performance in C-V2X scenariosYi, Wenxiong; Ma, Fei; Rao, Bowen; Yu, Xiaofan; Tan, Guoping; Zhou, Siyuan
doi: 10.1117/12.2627784pmid: N/A
In this paper we describe a hardware-in-the-loop platform (HIL) for evaluating the performance of On-Board-Unit (OBU) in C-V2X scenario. We use CARLA as the simulation environment to obtain high fidelity scenario data. In this platform we design the basic evaluation scenarios based on current standards and then design random scenario parameters for obtaining a large number of test scenarios with different parameters to test the robustness of the algorithm. The key scenario parameters are stored while the scenario is running and are used to analyze and evaluate the performance of the algorithm at the end of the scenario and to produce an evaluation report, a use case is provided in the text to demonstrate the overall usefulness of the platform.
Simulation analysis of indoor orbital inspection robot based on GazeboFang, Shu-juan
doi: 10.1117/12.2628608pmid: N/A
In order to reduce the complicated daily inspection tasks of power system staffs and improve the inspection efficiency and accuracy, an indoor orbital inspection robot applied to the power industry is developed. The inspection robot includes robot body, track and background monitoring system. The walking system, lifting system and camera platform system of the robot are introduced, and the hardware control circuit and software system are developed. Based on the simulation environment Gazebo of the Robot Operating System(ROS), the robot model is created by two method. The first method is to create robot by using Gazebo model editor, and the second method is to create robot by software SolidWorks then model is exported to URDF file. The simulation results show, the robot model established by Gazebo model editor is more convenient for simulation optimization analysis.
Research on the traceable intelligent garbage classification system based on voice interactionWang, Yanyan; Lin, Ying; Yin, Xiaohong; Fang, Junlong; Lu, Zhaoji; Li, Kunyu; Luo, Guohao
doi: 10.1117/12.2627872pmid: N/A
At present, garbage classification mainly depends on manual work, with large classification workload, low efficiency and low user participation rate. Under the background of the gradual popularization of smart home in people's life, aiming at the unsatisfactory implementation of waste classification, a kind of traceable intelligent garbage classification system based on voice interaction was developed in this work. The voice interactive flexible garbage sorting bin in the system can realize automatic movement of the partition to adjust the regional capacity, and automatically recognize the garbage type by voice, so that users can start classification at home. In addition, the encrypted QR code was adopted to track the user's information so as to supervise the garbage classification and solve the first half of the problem of garbage classification.
Research on early warning of public opinion based on Internet of Things and text emotion analysisChen, Xiang; Chen, Chen; Gong, Siyuan; Liu, Shantong
doi: 10.1117/12.2627791pmid: N/A
Combine the networking process and text emotion analysis technology to build an early warning system of public opinion, which provides a basis for judging the emotional tendency of police Weibo and points out the direction for the future emotional analysis and research. Based on the emotion analysis method of emotion dictionary, this paper constructs the analysis model of emotion polarity, takes the related topics of police work as an example to verify the availability of the model, and finally carries on the correlation analysis to these information of Weibo and the emotion polarity. The emotional polarity analysis model of this paper has availability, there is a significant positive correlation between Weibo comments and retweets, and when the retweets are low, there is a significant negative correlation between comments and emotional polarity. And when the number of likes on Weibo is greater than the number of comments, Weibo content itself has a positive emotional tendency.
A network migrating framework based on CloudSimZhu, Leilei; Sui, Xin; Song, WenHao; Liu, RuiXiang; Liu, Dan; Li, Li
doi: 10.1117/12.2627859pmid: N/A
With the continuous expansion of cloud data center scale, the flow of network traffic generated by virtual machine scheduling also increased, resulting in a sharp increase of energy consumption in cloud data center. Under certain network topology, different virtual machine scheduling strategies would produce different network flow. Therefore, how to optimize the scheduling strategy and reduce network flow became the key factors to reduce the energy consumption of cloud datacenter. In this paper, based on the cloud computing simulation platform CloudSim, the network module was extended, adding the network communication module of virtual machine migrating. In order to ensure the stability of the network data center, a virtual machine scheduling algorithm NPABFD for network traffic and energy consumption aware was proposed. The experimental results showed that the NPABFD algorithm could effectively reduce the transfer traffic of migrating VMs in high-level switches, reduce the global NDC's global energy consumption and the migrating number of VMs.
Intelligent traffic detection with millimeter-wave radar and cameraZhang, Yingchao; Ma, Zhaoyou; Han, Wen; Li, Tao; Hou, Fujin; Song, Xiuguang
doi: 10.1117/12.2627800pmid: N/A
With the impact of COVID-19, more people are choosing to travel by private cars, which will cause problems such as traffic congestion. It is essential for traffic engineers to have real-time traffic volume, speed, and individual vehicle length. In this study, the ACC7350 millimeter-wave radar was tested, and its advantages and disadvantages were analyzed in vehicle speed, distance from the radar, and vehicle trajectory. The speed detection error between MWR and GPS was within 6%, and the distance detection error was 20%. Then the traffic flow detection results of the camera and millimeter-wave radar were compared and analyzed. Results show that the mistakes of traffic flow detection based on vision and MWR are 4% and 13%, respectively. Finally, we proposed a traffic data processing method combined with a camera-based target tracking algorithm.