检索结果-南通市图书馆

Optimal Control Method for On-Ramp Merging on Highways Considering Fairness and Safety

在线全文

学校读者我要写书评

暂无评论

Journal of Traffic and Transportation Engineering(English Edition) 2024年

作者： Sen Xia Haigen Min Yukun Fang Jianqiu Wang Jie Li Xiaobo Qu xiangmo zhao School of Information and Engineering， Chang'an University Innovation Center for Western China Traffic Safety and Intelligent Cooperative Control China Mobile (Shanghai) Information and Communication Technology Co.Ltd. Shandong Hi-Speed Information Group Co.Ltd. School of Vehicle and Mobility， Tsinghua University

On-ramp merging can generate a traffic bottleneck due to predictability and coordination issues between vehicles on the main road and those from the ramp， which may result in traffic congestion and accidents. Connected and automated vehicles (CAVs) with vehicle-to-everything(V2X) communication have the potential to improve vehicles coordination and facilitate merging. Current research mainly focuses on enhancing traffic efficiency and reducing fuel consumption， neglecting the importance of fairness in right-of-way allocation and vehicle safety during merging. Thus， in this study， a double-layer optimized ramp-merge control model is proposed， where the upper layer aims to determine the merging sequence considering both fairness and efficiency， and the lower layer focuses on trajectory optimization considering safety constraints. Simulation results show that the proposed method reduces driving delays by 28.88% on average compared with the first-in-first-out method， and decreases unfair delay percentage in the merging sequence by 76.38% on average compared with the short delay method， validating the advantage of the proposed method in both traffic efficiency and fairness. Furthermore， compared with the Hamiltonian analysis method and the boundary adjustment method， the proposed model significantly reduces security risks by 63.47% and 65.14% respectively. Comparison of the results of the proposed method with NGSIM data further demonstrates the effectiveness of the proposed method.

关键词：

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

基于车辆外观特征和帧间光流的目标跟踪算法

应用科学学报 2024年第1期42卷 103-118页

作者：李绍骞程鑫周经美赵祥模长安大学信息工程学院陕西西安710064 长安大学电子与控制工程学院陕西西安710064

在复杂道路场景下,车辆目标之间频繁遮挡、车辆目标之间相似的外观、目标整个运动过程中采用静态预设参数都会引起跟踪准确率下降等问题。该文提出了一种基于车辆外观特征和帧间光流的目标跟踪算法。首先,通过YOLOv5算法中的YOLOv5x网... 详细信息

在复杂道路场景下,车辆目标之间频繁遮挡、车辆目标之间相似的外观、目标整个运动过程中采用静态预设参数都会引起跟踪准确率下降等问题。该文提出了一种基于车辆外观特征和帧间光流的目标跟踪算法。首先,通过YOLOv5算法中的YOLOv5x网络模型获得车辆目标框的位置信息;其次,利用RAFT (recurrent all-pairs field transforms for optical flow)算法计算当前帧和前一帧之间的光流,并根据得到的位置信息对光流图进行裁剪;最后,在卡尔曼滤波过程中利用帧间光流进行补偿得到更精确的运动状态信息,并利用车辆外观特征和交并比特征完成轨迹匹配。实验结果表明,基于车辆外观特征和帧间光流的目标跟踪算法在MOT16数据集上表现良好,相较于跟踪算法DeepSORT,成功跟踪帧数占比提高了1.6%,跟踪准确度提升了1.3%,跟踪精度提升了0.6%,改进的车辆外观特征提取模型准确率在训练集和验证集上分别提高了1.7%、6.3%。因此,基于高精度的车辆外观特征模型结合关联帧间光流的运动状态信息能够有效实现交通场景下的车辆目标跟踪。

关键词：目标跟踪车辆外观特征帧间光流卡尔曼滤波

Complex field network-coded cooperation based on multi-user detection in wireless networks

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2013年第2期24卷 215-221页

作者： Jing Wang Xiangyang Liu Kaikai Chi xiangmo zhao School of Information Engineering Chang'an University State Key Laboratory of Integrated Service Networks Xidian University Department of Network Management Xi'an Communication College College of Computer Science and Technology Zhejiang University of Technology

Cooperative communication can achieve spatial diversity gains,and consequently combats signal fading due to multipath propagation in wireless networks powerfully.A novel complex field network-coded cooperation（CFNCC） scheme based on multi-user detection for the multiple unicast transmission is *** analysis and simulation results demonstrate that,compared with the conventional cooperation（CC） scheme and network-coded cooperation（NCC） scheme,CFNCC would obtain higher network throughput and consumes less time ***,a further investigation is made for the symbol error probability（SEP） performance of CFNCC scheme,and SEPs of CFNCC scheme are compared with those of NCC scheme in various scenarios for different signal to noise ratio（SNR） values.

关键词： network coding complex field wireless network cooperative communication multi-user detection

无信控交叉口网联车辆动态碰撞风险检测与预警策略

在线全文

学校读者我要写书评

暂无评论

计算机工程与应用 2024年第13期60卷 330-337页

作者：王润民凡海金何佳浚徐志刚赵祥模长安大学西部交通安全与智能控制省部共建协同创新中心西安710018 长安大学信息工程学院西安710018

针对无信控交叉口碰撞事故多发的问题,面向网联人工驾驶环境,研究提出了一种基于车车通信的无信控交叉口网联车辆碰撞动态风险检测与预警策略。在构建典型无信控交叉口场景的基础上,设计了一种基于多项式拟合的车辆轨迹模型;融合利用碰... 详细信息

针对无信控交叉口碰撞事故多发的问题,面向网联人工驾驶环境,研究提出了一种基于车车通信的无信控交叉口网联车辆碰撞动态风险检测与预警策略。在构建典型无信控交叉口场景的基础上,设计了一种基于多项式拟合的车辆轨迹模型;融合利用碰撞到达时间和风险暴露时间作为风险检测指标,构建了一种圆形-双圆车辆模型实现车辆碰撞风险检测;综合考虑了驾驶人异质性及其交互行为,提出一种基于博弈论和遗传算法的两级碰撞预警策略;基于SUMO搭建仿真环境对预警策略的有效性及适用性进行测试分析。结果表明,所提策略能够准确识别出所有的碰撞事件并触发预警,预警成功率达到100%;在不同比例驾驶人组成测试工况下,所提预警策略均能显著降低碰撞率和平均碰撞动能。

关键词：无信控交叉口网联车辆动态风险检测分级预警驾驶人异质性博弈论

Performance Analysis in SWIPT-Based Bidirectional D2D Communications in Cellular Networks

在线全文

学校读者我要写书评

暂无评论

China Communications 2023年第12期20卷 41-51页

作者： Yang Zhang Wei Wang xiangmo zhao Jun Hou School of Information Engineering Chang’an UniversityXi’an 710064China

In this paper,a novel traffic-aware cooperative cognitive radio network that can enable deviceto-device(D2D)communications in cellular system is proposed and *** providing relay cooperation to cellular transmission,D2D users can realize their own two-way communication in the licensed *** most existing works,in the proposed network,both wireless-powered D2D users can harvest energy via radio-frequency signals received from basic station(BS)through a hybrid protocol which can adaptively utilize both time-switching and powersplitting ***,D2D users perform decode-and-forward operation to transmit signals,and mobile user(MU)employs a selection combining *** addition,the performance of both D2D system and cellular system in the proposed network is evaluated by deriving the expressions of their exact outage probability and *** and simulation results validate correctness of derivations and reveal the influence of various system parameters of the proposed network.

关键词： D2D communication outage probability SWIPT

在线全文

学校读者我要写书评

暂无评论

驾驶行为分类方法及量化评估综述

汽车技术 2024年第5期 1-14页

作者：张立成张婷蔡学锐赵祥模彭琨长安大学西安710064 车联网教育部-中国移动联合实验室西安710064 陕西省车联网与智能汽车测试技术工程研究中心西安710064

对驾驶行为分类方法及量化评估进行综述,首先阐述了驾驶行为的涵义及表征方法,然后将驾驶行为分类方法划分为基于统计特性的分类方法、基于机器学习的分类方法、混合式(组合、集成)分类方法三大类,并对不同的驾驶行为分类方法的代表算... 详细信息

对驾驶行为分类方法及量化评估进行综述,首先阐述了驾驶行为的涵义及表征方法,然后将驾驶行为分类方法划分为基于统计特性的分类方法、基于机器学习的分类方法、混合式(组合、集成)分类方法三大类,并对不同的驾驶行为分类方法的代表算法、优点及局限性等进行系统归纳和总结,其次,从多个维度对驾驶行为的量化评估研究进行系统介绍,最后介绍了驾驶行为分类及量化评估研究成果在多个领域的应用现状及前景展望。

关键词：交通工程驾驶行为分类评估智能网联汽车交通安全节能减排舒适性

维普期刊数据库博看期刊

On-ramp merging strategy for connected and automated vehicles based on complete information static game

在线全文

学校读者我要写书评

暂无评论

Journal of Traffic and Transportation Engineering(English Edition) 2021年第4期8卷 582-595页

作者： Haigen Min Yukun Fang Xia Wu Guoyuan Wu xiangmo zhao School of Information Engineering Chang'an UniversityXi'an 710064China Department of Electrical and Computer EngineeringUniversity of CaliforniaRiversideCA 92521USA

Improper handling of vehicle on-ramp merging may hinder traffic flow and contribute to lower fuel economy,while also increasing the risk of *** control for connected and automated vehicles(CAVs)has the potential to significantly reduce negative environmental impact while also improve driving safety and traffic ***,in this paper,we focus on the scenario of CAVs on-ramp merging and propose a centralized control *** sequence(MS)allocation and motion planning are two key issues in this *** deal with these problems,we first propose an MS allocation method based on a complete information static game whereby the mixed-strategy Nash equilibrium is calculated for an individual vehicle to select its *** on-ramp merging problem is then formulated as a bi-objective(total fuel consumption and total travel time)optimization problem,to which optimal control based on Pontryagin's minimum principle(PMP)is applied to solve the motion planning *** determine the proper parameters in the bi-objective optimization problem,a varying-scale grid search method is proposed to explore possible solutions at different *** this method,an improved quicksort algorithm is designed to search for the Pareto front,and the(approximately)unbiased Pareto solution for the bi-objective optimization problem is finally determined as the optimal *** proposed on-ramp merging strategy is validated via numerical simulation,and comparison with other strategies demonstrates its effectiveness in terms of fuel economy and traffic efficiency.

关键词： Connected and automated vehicles On-ramp merging Complete information static game Optimal control Varying-scale grid search

Identification and optimization of traffic bottleneck with signal timing

在线全文

学校读者我要写书评

暂无评论

Journal of Traffic and Transportation Engineering(English Edition) 2014年第5期1卷 353-361页

作者： Shaoxin Yuan xiangmo zhao Yisheng An School of Information Engineering Chang'an University Department of Civil and Environmental Engineering University of Washington

In urban transportation network, traffic congestion is likely to occur at traffic bottlenecks. The signal timing at intersections together with static properties of left-turn and straight-through lanes of roads are two significant factors causing traffic bottlenecks. A discrete-time model of traffic bottleneck is hence developed to analyze these two factors, and a bottleneck indicator is introduced to estimate the comprehensive bottleneck degree of individual road in regional transportation networks universally, the identification approaches are presented to identify traffic bottlenecks, bottleneck-free roads, and bottle- neck-prone roads. Based on above work, the optimization method applies ant colony algorithm with ef- fective green time as decision variables to find out an optimal coordinated signal timing plan for a re- gional network. In addition, a real experimental transportation network is chosen to verify the valida- tion of bottleneck identification. The bottleneck identification approaches can explain the features of oc- currence and dissipation of traffic congestion in a certain extent, and the bottleneck optimization meth- od provides a new way to coordinate signal timing at intersections to mitigate traffic congestion.

关键词： traffic bottleneck bottleneck indicator signal timing coordination ant colony algorithm discrete-time model

Vehicle Ego-Localization Based on Streetscape Image Database Under Blind Area of Global Positioning System

在线全文

学校读者我要写书评

暂无评论

Journal of Shanghai Jiaotong university(Science) 2019年第1期24卷 122-129页

作者： ZHOU Jingmei zhao xiangmo CHENG Xin XU Zhigang zhao Huaixin School of Electronic and Control Engineering Chang'an University School of Information Engineering Chang'an University

Vehicle positioning is critical for inter-vehicle communication, navigation, vehicle monitoring and tracking. They are regarded as the core technology ensuring safety in everyday-driving. This paper proposes an enhanced vehicle ego-localization method based on streetscape image database. It is most useful in the global positioning system(GPS) blind area. Firstly, a database is built by collecting streetscape images, extracting dominant color feature and detecting speeded up robust feature(SURF) points. Secondly, an image that the vehicle shoots at one point is analyzed to find a matching image in the database by dynamic programming(DP)matching. According to the image similarity, several images with higher probabilities are selected to realize coarse positioning. Finally, different weights are set to the coordinates of the shooting location with the maximum similarity and its 8 neighborhoods according to the number of matching points, and then interpolating calculation is applied to complete accurate positioning. Experimental results show that the accuracy of this study is less than 1.5 m and its running time is about 3.6 s. These are basically in line with the practical need. The described system has an advantage of low cost, high reliability and strong resistance to signal interference, so it has a better practical value as compared with visual odometry(VO) and radio frequency identification(RFID) based approach for vehicle positioning in the case of GPS not working.

关键词： vehicle ego-localization global positioning system(GPS) blind area dominant color dynamic programming(DP) matching weighted interpolation