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191.
车牌自动识别系统设计与实现   总被引:3,自引:0,他引:3  
车牌自动识别分为图像预处理、车牌定位、字符分割、字符识别四步。利用形态学变换对图像进行滤波聚类,HOUGH变换对车牌图像进行水平校正,BP神经网络的方法进行字符识别,最后基于DELPHI7.0环境下设计开发了车牌自动识别系统。  相似文献   
192.
����GIS�Ľ�ͨ��ϢWeb���ⷢ��ϵͳӦ���о�   总被引:4,自引:1,他引:4  
针对目前智能交通系统中所采用的有限的交通信息发布手段,在对外发布的信息内容和数量都远远不能满足实际需要情况,运用系统的思想,对目前国内刚刚起步的,将互联网和先进的地理信息系统平台相结合起来对外发布交通信息的信息发布系统的基本原理、可行应用、一般系统构架等进行了研究.指出运用互联网可以提供大量的信息服务,而先进的地理信息系统平台能够处理、查询、分析、显示各种静态与动态的交通信息,二者的结合是交通信息发布的一个重要发展趋势,并特别通过一个实际系统探讨了一种当前经济可行系统的实现方式.  相似文献   
193.
智能交通系统中的公交车辆调度方法研究   总被引:17,自引:3,他引:17  
针对公交车辆调度现状及所处的运营环境 ,利用遗传算法 ( Genetic Algorithm,GA)的智能化特征 ,进行了公交车辆智能调度方法的研究。采用 GA的一点和二点交叉方式 ,确定了三种规模的不同调度方式。以北京 375路车运营线路为实例 ,得到了简洁的 GA公交车辆调度结果。仿真结果表明 ,该方法可有效地改善公交车辆运营调度优化效果 ,提高公交车辆的运营效率 ,为城市公交车辆智能化调度管理提供合理、有效的调度方法  相似文献   
194.
This study introduces a new CONnectivity ROBustness model (CONROB) to assess vehicle-to-vehicle communication in connected vehicle (CV) environments. CONROB is based on Newton’s universal law of gravitation and accounts for multiple factors affecting the connectivity in CV environments such as market penetration, wireless transmission range, spatial distribution of vehicles relative to each other, the spatial propagation of the wireless signal, and traffic density. The proposed methodology for the connectivity robustness calculation in CONROB accounts for the Link Expiration Time (LET) and the Route Expiration Time (RET) that are reflected in the stability of links between each two adjacent vehicles and the expiration time of communication routes between vehicles. Using a 117 sq-km (45-square mile) network in Washington County, located west of Portland city, Oregon, a microscopic simulation model (VISSIM) was built to verify CONROB model. A total of 45 scenarios were simulated for different traffic densities generated from five different traffic demand levels, three levels of market penetration (5%, 15%, and 25%), and three transmission range values [76 (250), 152 (500), and 305 (1000) m (ft)]. The simulation results show that the overall robustness increases as the market penetration increases, given the same transmission range, and relative traffic density. Similarly, the overall connectivity robustness increases as the relative traffic density increases for the same market penetration. More so, the connectivity robustness becomes more sensitive to the relative traffic density at higher values of transmission range and market penetration. Multiple regression analysis was conducted to show the significant effect of relative traffic density, transmission range, and market penetration on the robustness measure. The results of the study provide an evidence of the ability of the model to capture the effect of the different factors on the connectivity between vehicles, which provides a viable tool for assessing CV environments.  相似文献   
195.
‘Vehicle miles traveled’ (VMT) is an important performance measure for highway systems. Currently, VMT [or ‘annual average daily traffic’ (AADT)] is estimated from a combination of permanent counting stations and short-term counts done at specified locations as part of the Highway Performance Monitoring System (HPMS) mandated by the US Federal Highway Administration. However, on some roadway sections, Intelligent Transportation Systems (ITS) such as detectors and cameras also produce traffic data. The question addressed in this paper is whether and under what conditions ITS systems data could be used instead of HPMS short-term counts (called ‘coverage counts’)? This paper develops a methodology for determining a threshold number of missing daily traffic counts, or alternatively, the number of valid ITS data observations needed, in order to confidently replace the HPMS coverage counts with ITS data.

Because ITS counts, coverage counts, and actual ground counts (e.g. continuous counts) cannot be found coexisting on a roadway section, it is hard to compare them directly. In this paper, the Monte Carlo simulation method is employed to generate synthetic ITS counts and coverage counts from a set of relatively complete traffic counts collected at a continuous count station. Comparisons are made between simulated ITS counts, coverage counts, and actual ground counts. The simulation results indicate that when there are<330 daily traffic counts missing in a set of ITS counts in a year, that is, when there are at least 35 days of valid data, ITS counts can be used to derive a better AADT than using coverage counts. This result is applied to calculate the VMT for the Hampton Roads region in Virginia. The comparison between the VMTs derived with using and not using the threshold number indicates that these two VMTs are significantly different.  相似文献   
196.
大力发展智能交通系统是缓解成都市交通拥堵的有效手段之一.成都市已初步构建综合交通数据枢纽、智能交通技术支撑平台和智能交通应用系统.成都市“交通先行”的交通发展战略对ITS提出新需求.近期成都市ITS应以“一枢纽、七平台、多个应用系统、一套保障体系”为实施框架,未来建设完善的重点包括8项内容.  相似文献   
197.
编组站调度指挥智能化管理   总被引:1,自引:0,他引:1  
任广伟 《中国铁路》2009,(11):61-64
铁路编组站调度指挥智能化管理是智能交通系统(ITS)研究的一个重要领域,其依据编组站调度运输生产作业流程、性质和特点,运用智能交通管理理论,在对原编组站调度指挥信息管理系统进行系统优化和改造的基础上,采用新的调度作业组织模式,实现调度指挥的智能化管理,以达到减少人工作业环节,防止人为差错,提高运输效率的目的。  相似文献   
198.
介绍了我国智能运输系统(ITS)在城市交通管理、城市公共交通管理、公路和运输管理领域的应用情况,及国内代表性城市的应用进展。  相似文献   
199.
为了解决含有禁行路线路网中的最优路径求解问题.研究了含有装行路线路网的特点.建立了数学模型。通过路网转化法把含有禁行路线的路网转化为不含禁行路线的路网.降低了最优路径求解的难度。采用邻接结点关系矩阵和邻接结点权矩阵表达路网中结点和路段的拓扑关系,减少了路网的存储空间。用动态邻接结点关系矩阵和邻接结点权矩阵对经典的Dijkstra算法进行了改进,节省了计算机存储空间、提高了计算效率.并给出了基本算法。将所研究的路网转化方法和改进的Dijkstra算法应用于所研发的车辆诱导系统软件,并进行了实际测试。测试结果表明.府用该方法能够在含有禁行路线的路网中求解最优路径.且运算效率较高。  相似文献   
200.
User-centric intelligent mobility businesses emerge and prosper in Asian metropolitan areas by utilizing the progress if information and communication technology (ICT). Under the rise of private lead initiatives on intelligent transport systems (ITS), the roles of public sectors are still large. Public sectors should precisely identify the extensive ITS services by considering the regional conditions and deploy them by collaboration between the public and private. Public sectors also are strongly encouraged to identify the benefits acquired by development and compliance of the international technical standards. Furthermore, in order to maximize the potential capacity of ICT, improvements of social infrastructures are required by the public sectors together with private businesses. With the realization of the collaboration works, Asian regions are well deserved to take the lead in future ITS initiatives.  相似文献   
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