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921.
基于AHP的高速公路机电维护质量的模糊评价模型   总被引:1,自引:0,他引:1  
采用层次分析法建立高速公路机电系统维护质量评价体系,通过维护质量的影响因素两两比较形成不同层次判断矩阵,以判断矩阵的最大特征根对应的归一化特征向量作为模糊评价的各元素权重向量,应用于三级模糊综合评价,建立了基于AHP的高速公路机电维护质量的模糊评价模型。通过实例分析表明,基于层次分析法的高速公路机电维护质量的模糊评价模型计算较为客观和稳定,具有较好的评价效果。  相似文献   
922.
联网收费系统能够实时记录交通流量、行程时间、OD等大量信息,是先进的交通信息采集系统。鉴于此,论述河南省高速公路交通情况调查与联网收费数据相结合的应用实践,以实例说明高速公路交通情况调查的实现过程,可供同行参考与借鉴。  相似文献   
923.
高速公路的快速发展及公路客运场站布局规划的调整,特别是客运场站的外移,给中心城市的公路旅客运输组织带来了新的研究课题.因此,有必要重新审视原有的高速公路旅客运输组织模式,建立与高速公路交通网络相适应的运输组织模式.  相似文献   
924.
根据养护作业内容,通过对养护机械的合理配置,确定高速公路养护半径.  相似文献   
925.
Although car-following behavior is the core component of microscopic traffic simulation, intelligent transportation systems, and advanced driver assistance systems, the adequacy of the existing car-following models for Chinese drivers has not been investigated with real-world data yet. To address this gap, five representative car-following models were calibrated and evaluated for Shanghai drivers, using 2100 urban-expressway car-following periods extracted from the 161,055 km of driving data collected in the Shanghai Naturalistic Driving Study (SH-NDS). The models were calibrated for each of the 42 subject drivers, and their capabilities of predicting the drivers’ car-following behavior were evaluated.The results show that the intelligent driver model (IDM) has good transferability to model traffic situations not presented in calibration, and it performs best among the evaluated models. Compared to the Wiedemann 99 model used by VISSIM®, the IDM is easier to calibrate and demonstrates a better and more stable performance. These advantages justify its suitability for microscopic traffic simulation tools in Shanghai and likely in other regions of China. Additionally, considerable behavioral differences among different drivers were found, which demonstrates a need for archetypes of a variety of drivers to build a traffic mix in simulation. By comparing calibrated and observed values of the IDM parameters, this study found that (1) interpretable calibrated model parameters are linked with corresponding observable parameters in real world, but they are not necessarily numerically equivalent; and (2) parameters that can be measured in reality also need to be calibrated if better trajectory reproducing capability are to be achieved.  相似文献   
926.
Travel time is an effective measure of roadway traffic conditions. The provision of accurate travel time information enables travelers to make smart decisions about departure time, route choice and congestion avoidance. Based on a vast amount of probe vehicle data, this study proposes a simple but efficient pattern-matching method for travel time forecasting. Unlike previous approaches that directly employ travel time as the input variable, the proposed approach resorts to matching large-scale spatiotemporal traffic patterns for multi-step travel time forecasting. Specifically, the Gray-Level Co-occurrence Matrix (GLCM) is first employed to extract spatiotemporal traffic features. The Normalized Squared Differences (NSD) between the GLCMs of current and historical datasets serve as a basis for distance measurements of similar traffic patterns. Then, a screening process with a time constraint window is implemented for the selection of the best-matched candidates. Finally, future travel times are forecasted as a negative exponential weighted combination of each candidate’s experienced travel time for a given departure. The proposed approach is tested on Ring 2, which is a 32km urban expressway in Beijing, China. The intermediate procedures of the methodology are visualized by providing an in-depth quantitative analysis on the speed pattern matching and examples of matched speed contour plots. The prediction results confirm the desirable performance of the proposed approach and its robustness and effectiveness in various traffic conditions.  相似文献   
927.
Mobile communication instruments have made detecting traffic incidents possible by using floating traffic data. This paper studies the properties of traffic flow dynamics during incidents and proposes incident detection methods using floating data collected by probe vehicles equipped with on-board global positioning system (GPS) equipment. The proposed algorithms predict the time and location of traffic congestion caused by an incident. The detection rate and false rate of the models are examined using a traffic flow simulator, and the performance measures of the proposed methods are compared with those of previous methods.  相似文献   
928.
高速公路与地区经济发展   总被引:1,自引:0,他引:1  
本文讨论了高速公路经济效益的分类框架,效益分析,计算模型,以及高速公路与地区经济发展关系,对产业带、经济影响半径做了简要的论述。笔者在文中首先提出了“高速公路经济盲区”的概念。  相似文献   
929.
在转体前对转动体进行称重试验,测试转动体部分的不平衡力矩、偏心距、摩阻力矩及摩擦系数,为桥梁转体阶段的决策和施工提供依据。  相似文献   
930.
轨道交通亦庄线亦庄火车站,站后出入段线暗挖工程为单洞12.7 m宽大断面暗挖施工,且下穿京津高速公路,沉降控制严格,不允许进行降水。在这种条件下采取全断面注浆暗挖施工,在国内也没有十分成熟的施工经验。通过施工中的探索和实践,阐述全断面注浆止水、地面补偿注浆控制沉降等方面的内容,并对其效益进行分析评价。  相似文献   
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