An evolutionary game theory–based security model in vehicular ad hoc networks

The word population is growing on a daily basis; consequently, the growth of commute and transport, developing efficient and intelligent transportation systems (ITS), has become one of the most popular requirements and the most significant attempts in modern urban areas containing large population. A key component of intelligent transportation systems is a vehicular ad hoc network. Devising internet‐based practical programs such as awareness of climatic conditions, geographical location, practical programs like on‐line payment services in the vehicular ad hoc network has led to safer driving, prevention of deadly accidents, transportation improvement, more welfare and convenience for passengers, and even offering more commercial opportunities. The special features of vehicular ad hoc network, such as intense activity, constantly‐changing topology, the vehicles' high speed, etc, will lead to challenges in gaining security. Therefore, providing vehicular ad hoc networks with security is of extreme importance in terms of users' anonymity, identification, and data privacy. In this paper, a security model is presented using a method based on evolutionary games. This method, in every vehicle, is applied as a node in the network while interacting with other vehicles; it aims at distinguishing some common attacks and defending against attackers. In this method, defending (honest) vehicles and attacking vehicles take part in an asymmetrical game; each vehicle aims at gaining the most utility and achieving its goals. The proposed method is simulated using various scenarios. The simulation results reveal that the proposed method is efficient and it reaches equilibrium and convergence at the end of the game in each scenario.     

An Intelligent Transportation System Application for Smartphones Based on Vehicle Position Advertising and Route Sharing in Vehicular Ad-Hoc Networks

关于到来的紧急情况车辆和他们的线路警告司机能极大地在拥挤的城市里改进他们的旅行时间,当由于分心减少事故的风险时。这份报纸由建议耶稣,能够关于象救护车一样的到来的紧急情况车辆通知常规车辆的机器人应用,警察汽车和消防队贡献这个目标。这被创造能够直接在他们之间交流的车辆的一个网络使可能。因此,用户能由考虑到来的警戒以一种及时方式作开车决定。用我们的 GRCBox 硬件的支持,申请能在 5 GHz 乐队依靠车辆的特定的网络通讯, V2V (vehicle-to-vehicle ) 通讯通过基于机器人的 smartphone 和我们的 GRCBox 设备的联合正在被提供。申请与阻塞的不同层次在三种不同情形被测试,证明提供有能力第二在不到一个以内提醒起来注意 300 米,和通知车辆。     

1株桃果实采后病原真菌的鉴定以及碳源代谢指纹图谱分析

从采后贮藏过程中发病的八月脆桃果实（Amygdalus persica cv.Bayuecui）中分离到1株真菌菌株074#.通过对病原菌形态学观察以及核糖体ITS rDNA序列分析,证明菌株074#为灰葡萄孢霉菌（Botrytis elliptica）.致病性试验结果表明,桃果实为灰葡萄孢霉菌的寄主.通过Biolog FFMicroPlate分析该病原菌对95种碳源的利用能力,结果表明,Botrytis elliptica代谢指纹图谱为最适碳源包括D-果糖、蔗糖、L-苹果酸、琥珀酸、D-葡萄糖酸、L-天门冬氨酸、L-丝氨酸、腺苷、5＇-磷酸腺苷等26种,可利用碳源14种,不可利用碳源55种.     

协同学理论应用于ITS研究

研究利用协同学理论进行ITS研究的可行性和合理性,并利用协同学理论分析ITS.提出车流量是系统的控制参量,交通控制系统,交通流诱导系统是系统的序参量,并根据协同学理论处理复杂系统的一般步骤,基于协同学的役使原理,消去系统的快弛豫变量,建立系统的序参量方程,大大简化了方程的维数。     

基于3S的IVLNS技术研究实验平台

智能交通系统是21世纪城市交通的发展方向，智能车辆定位导航系统(IVLNS)是其核心，因此开发IVLNS技术研究的实验平台，具有十分重要的意义。阐述了自行研制的基于3S(GPS，GIS和GPRS)的IVLNS的组成，对各组成部分的功能及其实现进行了详细说明，对该系统的车载软件及相关技术进行了介绍，并给出了实验平台的初步实验结果。实验结果表明：该实验平台能够对车辆导航与定位，并为智能交通关键技术的进一步研究提供了基础。     

Analysis of V2V Broadcast Performance Limit for WAVE Communication Systems Using Two‐Ray Path Loss Model

The advent of wireless access in vehicular environments (WAVE) technology has improved the intelligence of transportation systems and enabled generic traffic problems to be solved automatically. Based on the IEEE 802.11p standard for vehicle‐to‐anything (V2X) communications, WAVE provides wireless links with latencies less than 100 ms to vehicles operating at speeds up to 200 km/h. To date, most research has been based on field test results. In contrast, this paper presents a numerical analysis of the V2X broadcast throughput limit using a path loss model. First, the maximum throughput and minimum delay limit were obtained from the MAC frame format of IEEE 802.11p. Second, the packet error probability was derived for additive white Gaussian noise and fading channel conditions. Finally, the maximum throughput limit of the system was derived from the packet error rate using a two‐ray path loss model for a typical highway topology. The throughput was analyzed for each data rate, which allowed the performance at the different data rates to be compared. The analysis method can be easily applied to different topologies by substituting an appropriate target path loss model.     

汽车牌照自动识别系统在公路收费口的应用

最近及未来的几年 ,上海市境内将建成多条高速公路 ,如何提高高速公路的服务质量 ,出入口的通行能力是一条比较重要的衡量标准。汽车牌照自动识别系统利用先进的摄像技术、图像识别技术和计算机技术 ,对抓拍图像进行正确分割和快速处理 ,自动识别出汽车的牌照号码 ,提升了高速公路的服务水平     

基于高通量测序分析不同浏阳豆豉中真菌的多样性

建立测定酱油中铅的氢化物原子荧光光谱法,同时以酱油为样本进行精密度和准确度测定,以及对酱油能力验证盲样考核样进行不确定度分析。结果表明,铅含量在0～100.00 ng/mL呈线性关系,相关系数（R）为0.999 8,该方法的检出限为0.74 μg/L,定量限为2.22 μg/L,精密度试验结果相对标准偏差（RSD）为1.16%～4.48%,回收率为93.3%～106.6%。2个盲样考核样不确定度结果分别为（0.940±0.092） mg/L和（0.460±0.035） mg/L,能力验证考核结果为满意。研究结果表明,采用水质分析质量控制工作程序对氢化物原子荧光光谱法测定酱油中铅进行分析质量控制,保证实验结果误差在可控制的范围内,获得高度可信的分析结果。     

一种动态路段行程时间的预测模型

动态路段行程时问的预测是ITS动态最短路线选择的关键技术之一。根据对实际交通状况的分析,将路段行程时间分为三个部分,即自由行驶时间、排队等待时间和通过交叉 口时间。模型基于路段的基本信息及实时信息分别对这三部分时间进行预测,从而实现对整段路段行程时间的动态预测,精确度明显提高。     

智能交通系统的发展状况研究

介绍了智能交通系统的概念和目标。阐述了智能变通系统的研究内容和目前的发展状况。结合智能交通系统存在问题和我国交通的实际情况,提出了我国智能交通系统的研究重点。