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41.
This study aims to examine how key aspects of voluntary climate action influence economic values of aviation carbon offsets using an Australian case study, where voluntary carbon offset programs for the aviation sector were active under a carbon tax between July 01, 2012 and July 17, 2014. An online survey was administered during the period using choice experiments. This rare and short-lived Australian experience is useful to gain insights into how individuals respond to the new public policy in terms of the perceived economic value of voluntary offsets for air travel. According to the estimation results, supporters of the mandatory tax policy held a welfare value of voluntary carbon offsets for their domestic flights that is three times larger than non-supporters (i.e., $AU27.83 vs. $AU9.40). It is $AU12.27 on average per ton of carbon offsets per person for domestic flights and $AU0.92 for international long-haul flights. The findings endorse that individuals seem to attach personal responsibility for carbon emissions (i.e. climate liability or carbon conscience) to frequent domestic flights, but not so much to intercontinental flights. Furthermore, reported flight frequencies by respondents did not place any significant impact on economic values of voluntary carbon offsets in both domestic and international frameworks. A coupled approach between forced choices and certainty responses was adapted, where no-choice options were retrieved, potentially improving choice experiments. Results suggest that airlines should consider simplifying their carbon offset programs to fixed levels (e.g. £3, £10, and £20 as in the case of British Airways), regardless of geographical boundaries, while governments should promote both mandatory and voluntary climate measures in tandem.  相似文献   
42.
Parents compete for high-quality education for their children by enrolling them in good schools. However, in a Chinese mega-city like Beijing, three factors jointly lead to the spatial separation between schools and homes: the centralized public goods provision mechanism, the historical dependency in school location, and the constrained supply of housing in downtown. Without an adequate number of school buses, this spatial separation of schools and homes triggers the numerous long-distance driving-to-school trips by private vehicle during workday morning rush hours in Beijing. We use the start and end dates of “school holiday” as exogenous repeated shocks to the aggregate traffic congestion, and employ the two-stage least squares (2SLS) regression approach to examine the congestion and pollution consequences of such driving-to-school trips in Beijing. We find that, all else being equal, workdays during school holidays have a traffic congestion index 20% lower than that of non-school-holiday workdays. Such a sharp reduction in congestion leads to a significant decrease in PM10 concentration. Policymakers should lower such “extra” congestion and environmental costs via optimizing the spatial balance between school supply and demand.  相似文献   
43.
港珠澳大桥将改变珠江口东西两岸之间的空间运输联系方式,从而改变整个珠三角地区的物流格局.从珠三角地区城市空间布局结构、产业特点出发,总结珠三角地区物流业特点,对港珠澳大桥影响珠三角物流格局的途径进行介绍;并逐一分析港珠澳大桥建成后对香港、深圳、珠海等珠三角主要城市物流业的不同影响.  相似文献   
44.
为了总结面向智能车辆的现役道路设施行驶适应性,即现役道路基础设施承载智能车辆行驶的适宜程度,阐述自主智能驾驶定义与驾驶自动化等级分类,在此基础上剖析不同等级间的人机功能差异,并分别从感知层、感知-决策层、决策-控制层探讨与道路设计要素相关联的人机功能差异,通过归纳总结智能车辆与道路几何要素、路面性能及其他道路要素(如道路标线)的相互作用机制研究,从道路工程角度及其他道路要素方面回顾该领域的研究现状,指出存在的问题和未来发展方向。研究结果表明:相比传统车辆,配置高等级自动驾驶系统的智能车辆对现役道路设施行驶适应性最高,主动安全系统次之,而驾驶辅助及有条件自动驾驶系统适应性不足。而目前研究主要问题包括:难以归纳、标定不同驾驶自动化等级间的人机功能差异及其对于道路设计参数的需求设计值;测试道路场景条件过于理想,考虑的驾驶自动化等级单一,试验规模和样本有限;道路几何、路面性能以及道路标志、标线等道路要素与智能车辆间的相互作用机制研究不足,缺乏与不同道路场景相匹配的智能车辆驾驶特征数据的获取手段。因此建议:重视并推动与道路设计要素相关联的关键人机功能差异指标信息共享;联合高保真且可交互的道路场景、高精度感知传感器物理模型、车辆动力学模型及微观交通流模型,利用测试场景自动化生成、极限工况场景搜寻与泛化等技术开展智能驾驶虚拟测试,突破现有研究的深度和广度;探索反映不同等级智能车辆的道路行驶适应性特征指标与评价标准,精准、有效地评估预测复杂道路场景及不利道路条件下的行驶适应性。  相似文献   
45.
This paper presents the results of a preference survey of 1545 respondents’ willingness to purchase electric vehicles (EVs) in Philadelphia. We pay particular attention to respondents’ willingness to pay for convenient charging systems and parking spaces. If the value of dedicated parking substantially outweighs the value of convenient charging systems, residential-based on-street charging systems are unlikely to ever be politically palatable. As expected, respondents are generally willing to pay for longer range, shorter charging times, lower operating costs, and shorter parking search times. For a typical respondent, a $100 per month parking charge decreases the odds of purchasing an EV by around 65%. Across mixed logit and latent class models, we find substantial variation in the willingness to pay for EV range, charge time, and ease of parking. Of note, we find two primary classes of respondents with substantially different EV preferences. The first class tends to live in multifamily housing units in central parts of the city and puts a high value on parking search time and the availability of on-street charging stations. The second class, whose members are likelier to be married, wealthy, conservative, and residing in single-family homes in more distant neighborhoods, are willing to pay more for EV range and charge time, but less for parking than the first group. They are also much likelier to consider purchasing EVs at all. We recommend that future research into EV adoption incorporate neighborhood-level features, like parking availability and average trip distances, which vary by neighborhood and almost certainly influence EV adoption.  相似文献   
46.
The increase of public attention, scientific research and political interest in environmental problems associated with transportation has provided the motivation for re-invention of electric vehicles. However the usage of grid-dependent EVs with a high-carbon electricity grid might produce more damage to the environment. This study aims to provide an environmental impact comparison of ICEVs, HEVs and EVs during their usage cycle, by modeling their energy consumption (electricity or fuel) and the supply chains of the supplied energy, (well-to-wheel) based on a life cycle assessment. The results show that running EVs with the existing mixed sources of electrical energy produce larger impacts on the environment 60% of the time; when compared to HEVs. When compared to ICEVs, EVs produce a larger environmental impact on 7 out of 15 environmental impact categories. Overall the environmental impacts of EVs are substantial based on the well-to-wheel analysis. It will continue to be so if no change is made to the methods of electricity generation in the near future. Given that the environmental profile of EVs is linked with the existing national electricity generation mix, the national electricity supply must be made cleaner before the electrification of the urban transport system.  相似文献   
47.
文章概述了STCW公约马尼拉修正案对航海技术专业修改的主要内容及影响,并从实践教学出发.分析了现阶段高职航海技术专业实践教学中师资队伍、教学实训设备、教学内容等方面存在的问题,提出了相应对策和建议.以期为履约过程中全面的教学改革提供思路。  相似文献   
48.
英国职业教育特色与启示   总被引:2,自引:0,他引:2  
文章介绍了中英职业教育合作项目的背景与进展,研究了英国当前的职业教育状况,分析了先进的教育经验.并对合作项目下的汽修课程体系改革作出了规划。  相似文献   
49.
公路工程投标报价的探讨   总被引:1,自引:0,他引:1  
从国内公路工程招投标工作的具体实践出发,探讨、分析投标报价,在帮助投标单位取得中标并获得更高施工利润的同时,希望能够与招标单位共同探讨:如何更加合理地开展投标报价,使其投标文件更具竞争性。  相似文献   
50.
航运协同中心机制创新改革,是广州航海学院创新强校工程的重中之重,对学院建设以及广东省航运业发展都具有重要的影响.本文紧密结合广州航海学院实际,在大力推进创新强校工程的大背景下,从航运协同中心机制创新改革的优势、面临的问题和困难、总体构想等方面进行探讨.  相似文献   
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