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1.
高职院校以"服务为宗旨、就业为导向",与地方经济发展相结合,积极探索实践教学的方法,搭建技能型人才培养实践教学体系推动行业与自身的可持续发展。以此为出发点,建立一个完整而完善的信号设备实训课程体系,不仅有利于专业自身的发展,同时也对其他院校有着一定的借鉴意义。从而减少一些重复的工作,推动省内院校轨道信号相关专业整体水平的提升。  相似文献   
2.
为了降低城市轨道交通中列车在站间运行的能耗, 研究了列车的站间节能驾驶策略, 在考虑线路限速和坡度的情况下, 建立了时间约束下的列车节能优化模型, 采用粒子群算法优化目标速度序列得出了列车节能驾驶策略。节能驾驶优化方法通过2个阶段来实现, 第1阶段在站间运行时间不变的情况下, 采用粒子群算法优化了列车在站间的节能驾驶策略, 得到了运行时间和能耗的关系, 第2阶段在多站间总运行时间不变的前提下, 将运行时间进行重新分配, 得到了列车在全线运行的节能驾驶策略。以北京地铁亦庄线实际线路数据和车辆参数为基础, 对优化方法进行仿真验证。仿真结果表明: 经过第1阶段的优化, 列车在万源街-荣京东街的单站间运行能耗降低了6.15%, 经过第2阶段的优化, 列车在多站间总运行能耗降低了14.77%。可见, 优化模型可以有效降低列车的运行能耗, 为列车时刻表的编制提供依据。  相似文献   
3.
利用微元法, 推导了钢轨感应电流的数学模型。以大秦铁路实时同步测试数据为基础, 分析了电气化铁道钢轨感应电流的形成机理、分布特性、影响因素及其对钢轨电压的影响。实测数据对比表明: 该模型误差在10%以内, 可以满足工程要求; 机车与牵引变电所的距离越大, 钢轨感应电流越大, 其分布为中间大, 两端小; 衰减常数越大, 钢轨感应电流越大, 感应电流饱和速度越快; 钢轨感应电流具有降低钢轨电压的效果, 机车与牵引变电所的距离越大, 效果越明显, 随着距离的增加, 感应电流对钢轨电流输入点的电压最大可以降低55%。  相似文献   
4.
中低速磁浮交通道岔系统工程设计   总被引:1,自引:0,他引:1  
道岔系统是保证中低速磁浮列车安全运行的重要转线系统.根据工程实际.对道岔系统的总体结构、组成及功能进行研究,详细分析道岔基础、轨排、接触轨、供电、控制系统,并提出工程实际中的设计计算方法和部分数据,论述道岔系统的设计思路、设计原则,以及工程实际中存在的问题.  相似文献   
5.
The objective of this study is to provide a strategic evaluation of the mitigation of CO2 emissions via modal substitution of high-speed rail for short-haul air travel on the Sydney–Melbourne, Australia city-pair from a life cycle perspective. It has been demonstrated that when considering CO2 emissions from vehicle operations, the modal shift from air to high-speed rail on this city-pair has the potential to provide a means of CO2 mitigation. However, uncertainty exists with regard to the level of mitigation potential when considering the whole-of-life performance of the systems. Given the significant difference in the infrastructure requirements between the air mode and the high-speed rail mode, this study quantifies the life cycle CO2 load attributable to each system and examines the effect on CO2 mitigation potential. The study concluded that while the inclusion of the linehaul infrastructure did increase the CO2 load associated with high-speed rail mode, it did not equate to or exceed the CO2 load per trip as experienced by the air mode. The avoided annual life cycle CO2 emission in the target year 2056 was 0.37 Mt representing an 18% reduction when compared to the air mode only on the city pair. In fact, the scenario comparison indicated that the substitution of high-speed rail for short-haul air travel on the city pair resulted in CO2 emissions avoidance throughout the longitudinal period.  相似文献   
6.
With the continuous expansion of urban rapid transit networks, disruptive incidents—such as station closures, train delays, and mechanical problems—have become more common, causing such problems as threats to passenger safety, delays in service, and so on. More importantly, these disruptions often have ripple effects that spread to other stations and lines. In order to provide better management and plan for emergencies, it has become important to identify such disruptions and evaluate their influence on travel times and delays. This paper proposes a novel approach to achieve these goals. It employs the tap-in and tap-out data on the distribution of passengers from smart cards collected by automated fare collection (AFC) facilities as well as past disruptions within networks. Three characteristic types of abnormal passenger flow are divided and analyzed, comprising (1) “missed” passengers who have left the system, (2) passengers who took detours, and (3) passengers who were delayed but continued their journeys. In addition, the suggested computing method, serving to estimate total delay times, was used to manage these disruptions. Finally, a real-world case study based on the Beijing metro network with the real tap-in and tap-out passenger data is presented.  相似文献   
7.
While the existing literature has focused on the short-term impacts, this paper investigates the long-term impacts of high-speed rail (HSR) competition on airlines. An analytical model is developed to study how an airline may change its network and market coverage when facing HSR competition on trunk routes. We show that prior to HSR competition, an airline is more likely to adopt a fully-connected network and cover fewer fringe markets if the trunk market is large. Under HSR competition, the airline will, for a given network structure, have a greater incentive to cover more fringe (regional or foreign) markets if the trunk market is large, or the airline network is close to hub-and-spoke. Further, the airline will, for any given market coverage, move towards a hub-and-spoke network when the trunk market is large, or the number of fringe markets covered by the airline network is large. Both effects are more prominent when the decreasing rate of airline density economies is large. We further show that HSR competition can induce the airline to adopt network structure and market coverage that are closer to the socially optimal ones, thereby suggesting a new source of welfare gain from HSR based on its long-term impacts on airlines. Implications for operators, policy makers and specific countries (such as China) are also discussed.  相似文献   
8.
A direct discrete mode choice model is introduced using relative attributes of competing modes as well as socioeconomic characteristics of travelers. The model is calibrated and validated for two available historic databases in the Dallas–Fort Worth region. The validation is conducted against the outputs of a current nested logit model used by the regional planning organization as well as the observed values based on transit ridership surveys for a newly inaugurated commuter rail service. The calibrated model is applied after the introduction of this new transit mode. The results show that the estimated mode shares by the proposed model have a statistically better consistency with the observed values than the estimates of the conventional nested logit model. Unlike the logit model, the structure of the direct model based on relative attributes also has the advantage of not needing recalibration each time a new travel mode is introduced. The model is found to be easier to calibrate and produces more accurate results than the nested logit model, commonly used by many metropolitan planning organizations.  相似文献   
9.
Short-term forecasting of high-speed rail (HSR) passenger flow provides daily ridership estimates that account for day-to-day demand variations in the near future (e.g., next week, next month). It is one of the most critical tasks in high-speed passenger rail planning, operational decision-making and dynamic operation adjustment. An accurate short-term HSR demand prediction provides a basis for effective rail revenue management. In this paper, a hybrid short-term demand forecasting approach is developed by combining the ensemble empirical mode decomposition (EEMD) and grey support vector machine (GSVM) models. There are three steps in this hybrid forecasting approach: (i) decompose short-term passenger flow data with noises into a number of intrinsic mode functions (IMFs) and a trend term; (ii) predict each IMF using GSVM calibrated by the particle swarm optimization (PSO); (iii) reconstruct the refined IMF components to produce the final predicted daily HSR passenger flow, where the PSO is also applied to achieve the optimal refactoring combination. This innovative hybrid approach is demonstrated with three typical origin–destination pairs along the Wuhan-Guangzhou HSR in China. Mean absolute percentage errors of the EEMD-GSVM predictions using testing sets are 6.7%, 5.1% and 6.5%, respectively, which are much lower than those of two existing forecasting approaches (support vector machine and autoregressive integrated moving average). Application results indicate that the proposed hybrid forecasting approach performs well in terms of prediction accuracy and is especially suitable for short-term HSR passenger flow forecasting.  相似文献   
10.
城市轨道建设的施工阶段作为整个工程中对周边地区负面影响较大的阶段,对其噪声进行治理有着十分重要的意义。本文通过研究城市轨道交通工程的建设过程,重点阐述地铁施工过程中产生的噪声污染情况,通过模型预测施工期噪声影响,从技术和管理层面分别开展施工期降噪技术研究,研究地铁施工可采用的噪声控制措施。  相似文献   
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