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21.
我国自然灾害频发,地震、洪水、泥石流等灾害极容易对道路,房屋等建筑造成巨大的损坏,从而对抢险过程直接或间接地增加了难度。为了高效遂行抢险任务和提高抢险能力,就有必要提高处理交通基础设施的能力。而抢险设备的选择和合理的配置能够大大提高抢险任务效率。一方面,对于不同的抢险任务,有着不同的作业内容,其中所需要的抢险器械也各不相同。另一方面,同一种工程机械又有着不同的型号,各自又具有独特的技术性能和适用范围。一种机械可以完成多种作业,而一种作业又可以使用多种工程机械。因此如何对工程机械的选择以及合理的配置是本文的重点。  相似文献   
22.
China’s transport industry is energy intensive and high-polluting. While with the surging urbanization and the development of service industry, China’s economic relies more and more on the transport sector. Therefore, exploring the relationship between transport energy-related carbon emission (TECE) and economic development is crucial to the realization of China’s “Post Paris” mitigation target. The paper carries out a decoupling research between TECE and Gross domestic product (GDP) at both national level and province level based on Logarithmic Mean Divisia Index (LMDI) decomposition analysis with the extended Kaya identity and Tapio decoupling model. The model quantifies eight factors’ effects on the relationship with focusing on external macro socio-economic related factors (i.e., spatial pattern, urbanization, per capita service industry output value, reciprocal of the service industry’s share of GDP, and demographic variable) successfully. The key conclusions are indicated as follows: (1) the national decoupling status was extensive coupling during 2004–2010 and then weak decoupling during 2010–2016. The progress can be attributed to the decline of energy intensity. (2) Per capita service output was always the prominent factor to promote carbon emissions growth in different time periods and provinces with inhibiting the advancement of decoupling process, followed by urbanization. (3) Scenario analysis shows that with the continuous growth of traffic demand and the promotion of urbanization, improving energy efficiency has become the key link to realize the decoupling between China’s TECE and its economy.  相似文献   
23.
在许多交通事故中,如果有安全座椅的保护,儿童可以避免死亡或受伤。家长们现在也意识到了安全座椅的重要性,但目前儿童安全座椅实际使用率却很低,这与儿童座椅本身的人性化设计有关。为了提高儿童安全座椅的舒适性和趣味性,文章从儿童身心特点出发,对儿童座椅造型、材料、功能方面的改良途径进行了探讨,提出了通过造型与材料的完美结合来实现座椅怀抱式感觉,增加趣味组件实现座椅趣味化,使用网络技术+智慧硬件实现座椅感知功能、交互功能等人性化改良途径。  相似文献   
24.
为研究智慧环境下课程资源建设,文章以《汽车空调原理与检修》课程建设应用为例,通过建设该教学平台,实现线上线下教学的有机结合,可以有效提升教师的教学质量及教学效率,还可以为那些渴望更深层次知识的学生提供一个良好的学习平台。在“智慧校园”的建设和发展过程中,需要不断更新与教学相关的信息,因此建设《汽车空调原理与检修》课程教学资源是高等院校课程改革的需求。  相似文献   
25.
Models for gasoline demand for transportation activities generally assume that demand is perfectly reversible with respect to gasoline price (and income). The small literature which relaxes the reversibility assumption in gasoline demand argues technological fixation leads to this asymmetry and utilizes aggregate time-series model to find evidence in favour of asymmetry. In this research it is suggested that there could also be behavioural factors behind this asymmetric response, possibly due to the loss aversion nature of human beings as described in the prospect theory. For the first time, household level data was used to understand asymmetry in gasoline demand in response to changes in gasoline price and income. There was statistical evidence that gasoline price and income both can induce asymmetric changes in gasoline demand among households. Specifically, elasticity with respect to rising prices and falling income is larger than the elasticity with respect to falling prices and rising income respectively, which is consistent with loss aversion in gasoline purchase behaviour. There was also some evidence of heterogeneity in the asymmetric responses between urban and rural households. The results have implications for transport-related energy tax policies or subsidies, while the method can be applied directly for non-energy goods as well.  相似文献   
26.
Transit agencies implement many strategies in order to provide an attractive transportation service. This article aims to evaluate the impacts of implementing a combination of strategies, designed to improve the bus transit service, on running time and passenger satisfaction. These strategies include using smart card fare collection, introducing limited-stop bus service, implementing reserved bus lanes, using articulated buses, and implementing transit signal priority (TSP). This study uses stop-level data collected from the Société de transport de Montréal (STM)’s automatic vehicle location (AVL) and automatic passenger count (APC) systems, in Montréal, Canada. The combination of these strategies has lead to a 10.5% decline in running time along the limited stop service compared to the regular service. The regular route running time has increased by 1% on average compared to the initial time period. The study also shows that riders are generally satisfied with the service improvements. They tend to overestimate the savings associated with the implementation of this combination of strategies by 3.5-6.0 min and by 2.5-4.1 min for both the regular route and the limited stop service, respectively. This study helps transit planners and policy makers to better understand the effects of implementing a combination of strategies to improve running time and passenger’s perception of these changes in service.  相似文献   
27.
Intergraph Smart 3D软件的电缆敷设功能在化工电力行业应用较为广泛,考虑到邮轮电气生产设计中的电缆具有长度长(3 000 km~5 000 km)、种类多、通道网络复杂和分段敷设的特点,直接应用Smart 3D原生的电缆敷设功能进行电缆敷设存在较大的风险。从邮轮电缆敷设需求出发,对Smart 3D原生电缆敷设解决方案进行优化,充分考虑电气设计人员的使用习惯,基于贪心算法和单源最短路径算法(Dijkstra算法)优化算法解决断续托架的电缆敷设和电缆分区敷设最优路径选取的问题,提高电气设计人员的电缆敷设效率。  相似文献   
28.
Map-matching (MM) algorithms integrate positioning data from a Global Positioning System (or a number of other positioning sensors) with a spatial road map with the aim of identifying the road segment on which a user (or a vehicle) is travelling and the location on that segment. Amongst the family of MM algorithms consisting of geometric, topological, probabilistic and advanced, topological MM (tMM) algorithms are relatively simple, easy and quick, enabling them to be implemented in real-time. Therefore, a tMM algorithm is used in many navigation devices manufactured by industry. However, existing tMM algorithms have a number of limitations which affect their performance relative to advanced MM algorithms. This paper demonstrates that it is possible by addressing these issues to significantly improve the performance of a tMM algorithm. This paper describes the development of an enhanced weight-based tMM algorithm in which the weights are determined from real-world field data using an optimisation technique. Two new weights for turn-restriction at junctions and link connectivity are introduced to improve the performance of matching, especially at junctions. A new procedure is developed for the initial map-matching process. Two consistency checks are introduced to minimise mismatches. The enhanced map-matching algorithm was tested using field data from dense urban areas and suburban areas. The algorithm identified 96.8% and 95.93% of the links correctly for positioning data collected in urban areas of central London and Washington, DC, respectively. In case of suburban area, in the west of London, the algorithm succeeded with 96.71% correct link identification with a horizontal accuracy of 9.81 m (2σ). This is superior to most existing topological MM algorithms and has the potential to support the navigation modules of many Intelligent Transport System (ITS) services.  相似文献   
29.
The use of fossil fuels in transportation generates harmful emissions that accounts for nearly half of the total pollutants in urban areas. Dealing with this issue, local authorities are dedicating specific efforts to seize the opportunity offered by new fuels and technological innovations in achieving a cleaner urban mobility. In fact, authorities are improving environmental performances of their public transport fleet by procuring cleaner vehicles, usually called low and zero emission vehicles (LEV and ZEV, respectively). Nevertheless there seems to be a lack of methodologies for supporting stakeholders in decisions related to the introduction of green vehicles, whose allocation should be performed since the network design process in order to optimize their available green capacity.In this paper, the problem of clean vehicle allocation in an existing public fleet is faced by introducing a method for solving the transit network design problem in a multimodal, demand elastic urban context dealing with the impacts deriving from transportation emissions.The solving procedure consists of a set of heuristics which includes a routine for route generation and a genetic algorithm for finding a sub-optimal set of routes with the associated frequencies.  相似文献   
30.
A modification to the transportation problem is outlined that aims to improve the quality of predictions of trip matrices, and at the same time, allow some behavioural and economic insights. A framework is suggested within which this modification may be made and a suitable statistic and iterative process are described. A simple example demonstrates the validity of the modification and suggests some areas of difficulty with the approach.  相似文献   
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