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基于相位差异技术的车载白天高分辨成像系统 预览
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作者 明名 陈涛 徐天爽 《光子学报》 EI CAS CSCD 北大核心 2019年第3期123-131,共9页
在1.2m车载望远镜的基础上,通过机上折轴卡塞格林焦点,将主光学系统与白天成像系统相连,实现了白天高分辨成像.该系统采用短波红外波段,在精密跟踪的同时,校正大气波前整体倾斜.近红外波段的双通道成像系统,通过在焦与离焦像面同时采集... 在1.2m车载望远镜的基础上,通过机上折轴卡塞格林焦点,将主光学系统与白天成像系统相连,实现了白天高分辨成像.该系统采用短波红外波段,在精密跟踪的同时,校正大气波前整体倾斜.近红外波段的双通道成像系统,通过在焦与离焦像面同时采集后,利用相位差异技术来提高成像分辨率.该系统探测能力达到5等星,成像分辨率接近两倍衍射极限,观测时间比自适应系统延长6h. 展开更多
关键词 车载式 光学望远镜 光学设计 成像分辨率 相位测量
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车载式底泥处理一体化设备结构及应用报告 预览
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作者 朱富春 何兵 +1 位作者 李银 余丹萍 《广州化工》 CAS 2019年第8期103-105,共3页
运用车载式底泥处理一体化设备,采用高分子絮凝剂(聚合氯化铝、聚丙烯酰胺)对深圳茅洲河1#底泥厂底泥进行絮凝脱水实验。通过对设备进料物质分析,得出底泥中含固率为10%,其中沙粒占50%左右,采用分级分筛系统,可提高单套一体化设备的处... 运用车载式底泥处理一体化设备,采用高分子絮凝剂(聚合氯化铝、聚丙烯酰胺)对深圳茅洲河1#底泥厂底泥进行絮凝脱水实验。通过对设备进料物质分析,得出底泥中含固率为10%,其中沙粒占50%左右,采用分级分筛系统,可提高单套一体化设备的处理能力。检测设备进料和设备出口处泥饼的含水率,发现在进料含水率在91%~97%范围内时,其脱水泥饼的含水率均低于60%,泥饼含水率为50.5%~58.9%。 展开更多
关键词 车载式 含水率 污泥脱水
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Vehicle-to-Infrastructure Channel Characterization in Urban Environment at 28 GHz 预览
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作者 Longhe Wang Bo Ai +4 位作者 Danping He Ke Guan Jiayi Zhang Junhyeong Kim Zhangdui Zhong 《中国通信:英文版》 SCIE CSCD 2019年第2期36-48,共13页
Both ultra-reliable low latency and high-data-rate communications are required by connective vehicles.Millimeter wave(mmWave)with large bandwidth is a key technology to support high-data-rate communications.In this pa... Both ultra-reliable low latency and high-data-rate communications are required by connective vehicles.Millimeter wave(mmWave)with large bandwidth is a key technology to support high-data-rate communications.In this paper,the 28 GHz wideband vehicle-to-infrastructure channel is characterized for the urban environment in a major street in Manhattan.The deployment of the transmitter and the receiver,as well as the traffic models,are selected by considering the recommendation by 3GPP TR 37.885.Ray tracing simulator with calibrated electromagnetic parameters is employed in this work to practically conduct intensive simulations.The 3D environment model is reconstructed from OpenStreetMap.The power delay profile,path loss,root-meansquare delay spread,K-factor and so on,are extracted from the calibrated simulation results.The evolution of the parameters,as well as their statistical properties,are analyzed and modeled.The work of this paper helps the researchers understand the propagation channel for designing mmWave technologies and communication system in a similar scenario. 展开更多
关键词 CHANNEL characterization mmWave CHANNEL RAY TRACING URBAN environment vehicular communication
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Fast Confidentiality-Preserving Authentication for Vehicular Ad Hoc Networks
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作者 MIRZAEE Siavash 蒋乐天 《上海交通大学学报:英文版》 EI 2019年第1期31-40,共10页
This paper studies the existing problems of message authentication protocols in vehicular ad hoc networks(VANETs) due to their significance in the future of commuting and transportation. Our contribution has been devo... This paper studies the existing problems of message authentication protocols in vehicular ad hoc networks(VANETs) due to their significance in the future of commuting and transportation. Our contribution has been devoted to implementing a new protocol for VANETs so that inherent security problems in past works are resolved. Exclusive security measures have been considered for the system which protects the users against threat of any attack. The new protocol shows a great hardness guaranteed by certificate based 80 bit security which assures messages to remain confidential in any time. Also, new unprecedented features like V2 X which improves system performance effectively have been instantiated. The simulation results indicate that message signature generation and verification both take place in much less time than present comparable rival protocols. 展开更多
关键词 message AUTHENTICATION protocol vehicular ad HOC networks(VANETs) SIGNATURE generation and verification
Edge Computing Based Applications in Vehicular Environments:Comparative Study and Main Issues
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作者 Leo Mendiboure Mohamed-Aymen Chalouf Francine Krief 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第4期869-886,共18页
Despite the expanded efforts,the vehicular ad-hoc networks(VANETs)are still facing many challenges such as network performances,network scalability and context-awareness.Many solutions have been proposed to overcome t... Despite the expanded efforts,the vehicular ad-hoc networks(VANETs)are still facing many challenges such as network performances,network scalability and context-awareness.Many solutions have been proposed to overcome these obstacles,and the edge computing,an extension of the cloud computing,is one of them.With edge computing,communication,storage and computational capabilities are brought closer to end users.This could offer many benefits to the global vehicular network including,for example,lower latency,network off-loading and context-awareness(location,environment factors,etc.).Different approaches of edge computing have been developed:mobile edge computing(MEC),fog computing(FC)and cloudlet are the main ones.After introducing the vehicular environment background,this paper aims to study and compare these different technologies.For that purpose their main features are compared and the state-of-the-art applications in VANETs are analyzed.In addition,MEC,FC,and cloudlet are classified and their suitability level is debated for different types of vehicular applications.Finally,some challenges and future research directions in the fields of edge computing and VANETs are discussed. 展开更多
关键词 CLOUD COMPUTING EDGE COMPUTING FOG COMPUTING CLOUDLET vehicular network
Trust Access Authentication in Vehicular Network Based on Blockchain 预览
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作者 Shaoyong Guo Xing Hu +3 位作者 Ziqiang Zhou Xinyan Wang Feng Qi Lifang Gao 《中国通信:英文版》 SCIE CSCD 2019年第6期18-30,共13页
Data sharing and privacy securing present extensive opportunities and challenges in vehicular network.This paper introducestrust access authentication scheme’as a mechanism to achieve real-time monitoring and promote... Data sharing and privacy securing present extensive opportunities and challenges in vehicular network.This paper introducestrust access authentication scheme’as a mechanism to achieve real-time monitoring and promote collaborative sharing for vehicles.Blockchain,which can provide secure authentication and protected privacy,is a crucial technology.However,traditional cloud computing performs poorly in supplying low-latency and fast-response services for moving vehicles.In this situation,edge computing enabled Blockchain network appeals to be a promising method,where moving vehicles can access storage or computing resource and get authenticated from Blockchain edge nodes directly.In this paper,a hierarchical architecture is proposed consist of vehicular network layer,Blockchain edge layer and Blockchain network layer.Through a authentication mechanism adopting digital signature algorithm,it achieves trusted authentication and ensures valid verification.Moreover,a caching scheme based on many-to-many matching is proposed to minimize average delivery delay of vehicles.Simulation results prove that the proposed caching scheme has a better performance than existing schemes based on central-ized model or edge caching strategy in terms of hit ratio and average delay. 展开更多
关键词 blockchain vehicular NETWORK EDGE COMPUTING AUTHENTICATION mechanism many-to-many MATCHING
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车载光学平台结构及其优化设计 预览
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作者 杨浩 杨永志 《光电技术应用》 2019年第3期61-64,共4页
根据高精密光学系统的工作环境条件,即要求车载光学平台具备良好的力学性能和隔振性能,制定了车载光学平台的结构设计方案。通过ANSYS对车载光学平台进行了静态、模态分析,获得静态应变及振动模态,从而对车载光学平台进行优化设计。车... 根据高精密光学系统的工作环境条件,即要求车载光学平台具备良好的力学性能和隔振性能,制定了车载光学平台的结构设计方案。通过ANSYS对车载光学平台进行了静态、模态分析,获得静态应变及振动模态,从而对车载光学平台进行优化设计。车载光学平台随载车进行了跑车试验和测试,结果显示,ANSYS仿真分析结果与测试结果相近,表明车载光学平台具有良好的稳定性,保证高精密光学系统能够稳定工作。 展开更多
关键词 高精密光学系统 车载 光学平台 ANSYS 试验和测试
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Road traffic accidents, near-misses and their associated factors among commercial tricycle drivers in a Nigerian city 预览
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作者 Ahmed Dahiru Balami Garba Sam 《健康与环境(英文)》 2019年第1期1-8,共8页
Tricycles form an important part of the intra-city transport system, following the ban placed on motorcycles in Maiduguri, Nigeria. However, no previous studies have been conducted to assess the occurrence of accident... Tricycles form an important part of the intra-city transport system, following the ban placed on motorcycles in Maiduguri, Nigeria. However, no previous studies have been conducted to assess the occurrence of accidents among them. The objective of this study was to determine the prevalence of road accidents, near-misses, and their associated factors among commercial tricycle drivers in Maiduguri. A cross-sectional study was conducted among registered commercial tricycle drivers in Maiduguri who had been in the business for at least a year. Data was collected through face-to-face interviews, using a structured questionnaire, and was subjected to bivariate and multivariate analysis using SPSS. The prevalence of road accidents and near misses were 46% and 50.3% respectively. Only six (3.9%) of respondents who had experienced a near-miss mentioned that they occurred while they were fully awake;during clear weather;and on a smooth, broad, and non-congested road. All the others had experienced the near miss under an unfavourable weather, road, and/or while feeling sleepy. In the bivariate analysis, only psycho-active substance use (χ^2=3.941;df =1;p=0.047) and having experienced more than one near miss (χ^2=31.807;df =1;p<0.001) were significantly associated with having an accidents. However, in the multivariate analysis, having experienced more than one near miss was the only factor which significantly predicted having an accident (OR=2.89 95% CI: 1.64-5.09;p<0.001). There is a need to conduct further intervention studies to determine the effectiveness of intervention measures in reducing accident rates among these tricycle drivers. 展开更多
关键词 road accident NEAR-MISS TRICYCLE vehicular FACTORS DRIVER FACTORS
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Lattice-Based Double-Authentication-Preventing Ring Signature for Security and Privacy in Vehicular Ad-Hoc Networks
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作者 Jinhui Liu Yong Yu +4 位作者 Jianwei Jia Shijia Wang Peiru Fan Houzhen Wang Huanguo Zhang 《清华大学学报自然科学版(英文版)》 EI CAS CSCD 2019年第5期575-584,共10页
Amidst the rapid development of the Internet of Things (loT), Vehicular Ad-Hoc NETwork (VANET), a typical loT application, are bringing an ever-larger number of intelligent and convenient services to the daily lives o... Amidst the rapid development of the Internet of Things (loT), Vehicular Ad-Hoc NETwork (VANET), a typical loT application, are bringing an ever-larger number of intelligent and convenient services to the daily lives of individuals. However, there remain challenges for VANETs in preserving privacy and security. In this paper, we propose the first lattice-based Double-Authentication-Preventing Ring Signature (DAPRS) and adopt it to propose a novel privacy-preserving authentication scheme for VANETs, offering the potential for security against quantum computers. The new construction is proven secure against chosen message attacks. Our scheme is more efficient than other ring signature in terms of the time cost of the message signing phase and verification phase, and also in terms of signature length. Analyses of security and efficiency demonstrate that our proposed scheme is provably secure and efficient in the application. 展开更多
关键词 Vehicular AD-HOC NETwork(VANET) PRIVACY security Double-Authentication-Preventing Ring Signature(DAPRS) LATTICE
Cooperative Intelligence for Autonomous Driving 预览
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作者 CHENG Xiang DUAN Dongliang +1 位作者 YANG Liuqing ZHENG Nanning 《中兴通讯技术:英文版》 2019年第2期44-50,共7页
Autonomous driving is an emerging technology attracting interests from various sectors in recent years.Most of existing work treats autonomous vehicles as isolated individuals and has focused on developing separate in... Autonomous driving is an emerging technology attracting interests from various sectors in recent years.Most of existing work treats autonomous vehicles as isolated individuals and has focused on developing separate intelligent modules.In this paper,we attempt to exploit the connectivity among vehicles and propose a systematic framework to develop autonomous driving techniques.We first introduce a general hierarchical information fusion framework for cooperative sensing to obtain global situational awareness for vehicles.Following this,a cooperative intelligence framework is proposed for autonomous driving systems.This general framework can guide the development of data collection,sharing and processing strategies to realize different intelligent functions in autonomous driving. 展开更多
关键词 AUTONOMOUS driving COOPERATIVE INTELLIGENCE information FUSION vehicular COMMUNICATIONS and NETWORKING
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车载式果园静电喷雾机的研制 预览
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作者 薛杨春 崔恩 党革荣 《安徽农业科学》 CAS 2018年第19期188-190,203共4页
针对目前果园施药过程中耗时费力及环境日益恶化的问题,设计了一款轻便、高效、省药、能减少对环境的污染、悬挂于农用三轮车尾部的果园静电自动喷雾机。该喷雾机有效减小了劳动强度,降低了农药施用量,高效低污染。因此,这种新型的车载... 针对目前果园施药过程中耗时费力及环境日益恶化的问题,设计了一款轻便、高效、省药、能减少对环境的污染、悬挂于农用三轮车尾部的果园静电自动喷雾机。该喷雾机有效减小了劳动强度,降低了农药施用量,高效低污染。因此,这种新型的车载果园静电喷雾机具有良好的推广应用前景。 展开更多
关键词 果园喷雾机 设计 车载式
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A Novel Range-Free Jammer Localization Solution in Wireless Network by Using PSO Algorithm 预览
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作者 LiangPang Xiao Chen +1 位作者 Zhi Xue Rida Khatoun 《国际计算机前沿大会会议论文集》 2017年第2期46-48,共3页
In wireless networks, jamming attacks are easy to launch and can significantly impact the network performance. The technique which localizes the jamming attacker is useful to address this problem. Some range-based loc... In wireless networks, jamming attacks are easy to launch and can significantly impact the network performance. The technique which localizes the jamming attacker is useful to address this problem. Some range-based localization schemes depend on the additional hardware of wireless nodes too much, and they can not work in resource-constrained wireless networks. Solutions in range-free localization are being pursued as a cost-effective alternative to more expensive range-based approaches.In this paper, we propose a novel range-free algorithm to localize the source of the attacker. We show that our approach only relies on the positions of each jammed or no-jammed node in the network, PSO algorithm is used to get the minimum covering circle of jammed positions and the circle center is the estimated jammer location. We compare our work with some existing range-free solutions via extensive simulations in two models, which are wireless sensor network (WSN) and vehicular ad hoc network (VANET) respectively. The experimental results suggest that our proposed algorithm achieves higher accuracy than the other solutions, and the localization error goes down with larger number of recorded jammed positions. In additional, when the recorded jammed positions are distributed in a specific constrained area, the localization error goes higher, we also propose an improved PSO algorithm to deal with this issue. 展开更多
关键词 Jamming ATTACK JAMMER LOCALIZATION Vehicular ad hoc NETWORK (VANET) Wireless sensor NETWORK (WSN) PSO Minimum covering circle
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车载卫星双向时间同步系统研究 预览
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作者 张金涛 魏海涛 +1 位作者 李隽 郑晓冬 《无线电工程》 2016年第11期51-54,共4页
卫星双向时间频率传递技术是高精度时间频率远程比对的基本手段。对设备时延进行校准是获得高精度时间比对的关键。设计了车载卫星双向时间同步系统,描述了系统设备组成、工作原理及各设备的功能特点,并对关键技术的实现进行了分析。设... 卫星双向时间频率传递技术是高精度时间频率远程比对的基本手段。对设备时延进行校准是获得高精度时间比对的关键。设计了车载卫星双向时间同步系统,描述了系统设备组成、工作原理及各设备的功能特点,并对关键技术的实现进行了分析。设计并完成了同源零基线验证实验。实验结果表明,车载卫星双向时间同步系统时延不确定度在0.4 ns之内,可以完成对卫星双向时间比对链路设备时延高精度的校准。 展开更多
关键词 双向时间同步 设备时延 车载 零基线
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Improving Traffic Conditions by Using Neural Networks 预览
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作者 Erick Cervantes C. José A. Castán R. +5 位作者 Salvador Ibarra M. Julio Laria M. Javier Guzmán O. Mayra G. Trevino B. Emilio Castán R. 《计算机技术与应用:英文版》 2016年第1期46-56,共11页
The paper promotes the implementation of a neural network approach to improve one of the most transcendent traffic conditions: the mobility of the cars in any particular junction. Neural networks have proven to be an ... The paper promotes the implementation of a neural network approach to improve one of the most transcendent traffic conditions: the mobility of the cars in any particular junction. Neural networks have proven to be an effective paradigm of modern computing, providing extensive benefits in a wide range of applications. In this sense, the paper uses a BPNN (backpropagation neural network) model. The three input nodes are related to: n1: the amount of cars in the road; n2: the green light interval; and n3:the distance (taking into account the quantity of cars) between the first car in the intersection and the last car in the longest line in front of it. In particular, the paper promotes that each traffic light signal will be capable of offering a new green light interval according to the requirement and constrains of the vitality, ensuring a vehicular mobility level greater than 65%. To assess this idea, the paper presents two experiments confronting the real world data versus experimental results. For example, in the first experiment, the BPNN improves the performance of the real data about vehicular mobility in almost 30%. Finally, some conclusions and future work are presented. 展开更多
关键词 TRAFFIC conditions NEURAL networks INTELLIGENT transport systems vehicular MOBILITY
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车载虚拟仪表及诊断系统的设计与实现 预览 被引量:3
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作者 刘善坤 窦立谦 +1 位作者 宗群 苟鹏程 《计算机应用与软件》 CSCD 2016年第8期229-233,248共6页
论述基于Android平台的车载虚拟仪表及诊断系统的软硬件设计过程。在具体实现上,利用ARM+Android体系构建终端仪表装置,在此基础上完成Android下CAN驱动的移植、车辆数据采集、图形化虚拟仪表显示以及故障诊断等功能。该装置借助Andr... 论述基于Android平台的车载虚拟仪表及诊断系统的软硬件设计过程。在具体实现上,利用ARM+Android体系构建终端仪表装置,在此基础上完成Android下CAN驱动的移植、车辆数据采集、图形化虚拟仪表显示以及故障诊断等功能。该装置借助Android特有的SurfaceView类实现了将车辆状态数据以图形化的方式展现在LCD触摸屏上,从而取代了传统的仪表盘。此外,还可以实时监测汽车运行和各ECU工作状态。当出现故障时,进行诊断,并第一时间为车主提供故障详情及维修建议。最后,采用dSPACE实时仿真系统与本装置构成闭环的测试系统来进行硬件在环(HIL)仿真测试,结果证明该装置性能稳定、显示效果良好,故障诊断功能全面、准确。 展开更多
关键词 车载 虚拟仪表 SurfaceView CAN通信 故障诊断
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一种卫星通信车载/便携终端的设计 预览 被引量:1
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作者 李红英 华煜 《机械与电子》 2016年第8期26-28,共3页
介绍了一种新型的天线和通信主机高度集成的一体化卫星通信终端,具有体积小、质量轻、使用方便、安全可靠,防水、防盐雾、抗冲击振动的特点,适用车载及野外背负使用。针对其外观造型和结构设计进行阐述,可为同类的卫星通信终端提供一种... 介绍了一种新型的天线和通信主机高度集成的一体化卫星通信终端,具有体积小、质量轻、使用方便、安全可靠,防水、防盐雾、抗冲击振动的特点,适用车载及野外背负使用。针对其外观造型和结构设计进行阐述,可为同类的卫星通信终端提供一种新思路。 展开更多
关键词 卫星通信 车载 便携 外观 结构设计
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车载式消磁站消磁能力综述 预览
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作者 王志飞 陈金凤 +1 位作者 杨辉 高嵬 《船电技术》 2016年第1期42-44,共3页
本文在分析消磁站在现代舰船及海战当中作用的基础上,介绍了车载式消磁站的意义和前景,通过分析其原理,对其消磁能力进行了系统的梳理和归纳,为该类型消磁站的更广泛应用指明了方向。
关键词 车载式 消磁站 消磁
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车载式火化机助燃风二次预热设计 预览
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作者 高源 孟浩 钱高 《工业加热》 CAS 2016年第5期13-15,共3页
介绍了一种在率载式遗体火化设备中应用的空气预热设计,在助燃风设计上,通过采用二次预热的设计思路,可大幅提升助燃风的预热温度,提高火化效率。
关键词 车载式 火化机 预热器 燃烧效率
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基于车载式照明检测系统的路灯等照度曲线检测
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作者 宋金德 《中国照明电器》 2016年第2期38-40,共3页
根据城市道路照明行业的特点和需要,以及近年来对道路照明效果的检测和研究经验,系统地介绍1种基于车载式道路照明检测系统的路灯等照度曲线检测方法,可直接在路灯现场快速、方便地完成路灯等照度曲线的检测和数据分析,此方法具有测量... 根据城市道路照明行业的特点和需要,以及近年来对道路照明效果的检测和研究经验,系统地介绍1种基于车载式道路照明检测系统的路灯等照度曲线检测方法,可直接在路灯现场快速、方便地完成路灯等照度曲线的检测和数据分析,此方法具有测量效率高、准确性高和安全可靠等优点。 展开更多
关键词 车载式 检测系统 路灯 等照度曲线 现场检测 数据分析
基于车联网技术的醉酒禁驾系统的设计 预览
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作者 郭瞻 肖祖铭 周云鹏 《南昌师范学院学报》 2015年第6期43-46,共4页
该系统以单片机为核心,利用酒精传感器检测驾驶员的酒精浓度,如果酒精超标则禁止汽车的运行,并通过车联网技术将醉驾信息发送到家人和交警指挥监控平台,便于交警部门对酒驾车辆进行有效监管和控制。
关键词 醉酒禁驾系统 车联网技术 车载式
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