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181.
面向ITS的GIS研究与设计   总被引:6,自引:2,他引:6  
地理信息系统在智能交通系统中起着重要作用,是基础子系统和功能子系统的集成。在面向ITS的GIS设计中,系统框架采用B S结构,系统功能分为4部分:数据采集、数据管理、空间分析和系统维护与刷新。在此基础上设计图层和数据库,并给出应用界面。这样的设计是合理和可行的,已经用于兰州市智能交通系统建设中。文章最后还列举了面向ITS的GIS亟需解决的问题。  相似文献   
182.
王少军  张志  詹云军 《公路》2003,(3):45-49
在公路可行性研究工程地质勘察阶段,使用美国陆地卫星7的ETM 信息及其增强信息,探调了西藏波蜜-墨脱公路方案线的公路地质背景条件,并对沿线不同地段、重点工程的不良地质进行了分析。这一研究为青藏高原这个特殊地理单元上应用遥感技术进行公路方案线的选择、优化提供了操作性极强的方法与技术体系。  相似文献   
183.
针对环形感应线圈采集数据的特点,讨论一种基于动态时间弯曲(DTW)算法的车型分类新方法。由于采样波形与车速、车辆自身结构以及其通过线圈时的相对位置有关,导致实际同类车辆波形存在伸长、压缩,甚至波形残缺不全或局部振荡等复杂情况。为此,本方法首先对样本数据进行降噪滤波,补齐不完整信号等预处理;熟后结合DTW方法和最优聚类分析原理选取同类车型的多个模板,综合考虑误纳与误拒情况,可降低单模板匹配存在的误拒率;最后利用DTW算法和多个分类区分度指标进行多模板匹配,得出分类结论。论文仿真部分以一类车型为例,分析了本文方法与其他方法比较存在的优势。  相似文献   
184.
浅析高校图书馆的信息资源建设   总被引:1,自引:0,他引:1  
文章简要分析了高校图书馆信息资源建设的现状,就如何提高信息资源建设水平,从制定合理的藏书原则、科学认真地做好采访工作、加强虚拟馆藏建设、建立馆藏特色数据库、妥善处理信息资源建设中的几个关系、全面提高采访人员素质等六方面提出了工作思路,从而更好地为学校的教学科研提供高质量的文献信息保障.  相似文献   
185.
通过国内外各种出租车运行方式的比较,结合上海的现状,对上海现今的出租车业务流程进行改革,并基于信息系统建立新的运行模式,在提高地区出租车服务水平(提高载客率)和降低出租车总体运营成本两者之间取得平衡.  相似文献   
186.
张显满 《中国造船》2000,41(1):69-72
在信息战概念的基础上,分析现有水面舰艇作战系统设计的缺陷,从提高信息利用角度和资源共享角度,提出利用局域网技术,实现武器系统之间信息的横向交换。通过对所述系统的分析,证明这种方案是一种效费比较高、适应信息战要求的一种选择。  相似文献   
187.
基于信息素养教育的文献检索课程的教学改革   总被引:5,自引:0,他引:5  
文献检索课的培养目的应该定位在信息素养教育上,培养学生对信息的搜集、整理、利用能力是文献检索课的全新理念。拓展教育内容,改变教学方法,评价标准和提高教师信息素养均为改革文献检索课教学和加强信息素养教育的有效途径。  相似文献   
188.
陈亚杰  王洋  葛灵佳  葛永达 《船舶工程》2017,39(S1):290-292
在企业信息化建设过程中,普遍存在不同时期建设的信息系统中的用户管理、权限控制和日志审计管理各不相同,在对信息系统的运维管理提出较高要求的同时,也关系着企业的信息安全。结合国内科研院所企业信息系统建设现状,提出设计开发一套基于构件的权限控制安全平台,实现统一授权和审计管理并成功应用,提高了企业的信息系统运维管理效率,加强企业信息系统的安全性能。  相似文献   
189.
Without questioning the fact that to achieve efficiency emitters should pay for the true costs of their actions (a core principle of economic policies such as pollution taxes), we find sufficient evidence in the literature to demonstrate that many other policy instruments can be used in combination with taxes and permits to ensure that the transport needs of the present generation can be met without compromising the ability of future generations to meet any needs of their own.The policies and policy aspects considered in this paper broadly fall into three categories: physical policies, soft policies, and knowledge policies. All three aim to bring about changes in consumers’ and firms’ behaviour, but in different ways. The first category includes policies with a physical infrastructure element: public transport, land use, walking and cycling, road construction, and freight transport. We also consider the particular challenges for mobility in developing countries, and how these may be addressed. Soft policies, on the other hand, are non-tangible aiming to bring about behavioural change by informing actors about the consequences of their transport choices, and potentially persuading them to change their behaviour. These measures include car sharing and car pooling, teleworking and teleshopping, eco-driving, as well as general information and advertising campaigns. Finally, knowledge policies emphasise the important role of investment in research and development for a sustainable model of mobility for the future.The main findings can be summarised as follows.

Physical policies

An increase in the use of public transport, combined with a decrease in the use of private cars, can reduce traffic congestion and, more importantly, carbon dioxide (CO2) emissions, as public transport generally causes lower CO2 emissions per passenger kilometre than private cars. Public transport fares are subsidised in most places, which can be justified by economies of scale and by the fact that public transport can reduce total road transport externalities. London, Singapore, Portland and Curitiba are all examples of good practice at government level, having achieved reliable, frequent and integrated public transport.Policies to increase public transport use must be part of an integrated policy. Integrated policy refers to integration across different modes of transport, different government objectives (such as the economy, health and the environment), considering the needs of different social groups, and coordinating action between the relevant government institutions. There is evidence that a lack of coordination can jeopardise the achievement of policy objectives.A sustainable model for transport policy also requires integration with land-use policies. These may be somewhat limited within the bounds of existing cities, but as cities grow and new cities are built, urban planners must put more emphasis on land use for sustainable transport in order to reduce congestion and CO2 emissions. Sustainable land-use policy can direct urban development towards a form that allows public transport as well as walking and cycling to be at the core of urban mobility.Walking and cycling, which improve general health and produce no tailpipe emissions, constitute an excellent alternative to motorised transport on short-distance trips within towns and cities. The policies which can incentivise walking and cycling include crime reduction to make streets safer, well-maintained and clean pavements, attractive street furniture, safe crossings with shorter waiting times, dedicated cycle paths, showers in offices, and lower speed limits, to name but a few.Road construction and expansion used to be seen as one of the most promising ways to reduce traffic congestion. However, in the mid-1990s, the issue was reassessed and it was found that building and expanding roads, increased, rather than decreased, congestion, and ultimately induced higher levels of travel demand. The reason for this is that the extra capacity reduces the general cost of travelling and the less expensive the travel, the more it will be demanded. Regarding freight modal shift, road transport is much more polluting than rail per tonne-km of goods transported and therefore a shift towards greater use of rail in freight transport is desirable. Inadequate infrastructure is the main obstacle preventing this modal shift taking place.Developing countries face great mobility challenges: rural areas are often extremely poorly connected to transport infrastructure, such that, in contrast to the situation in developed countries, the benefits of road construction can strongly outweigh the total costs (including environmental ones). The main challenge, however, is to develop a solution to the problems arising from the combination of urbanisation and motorisation. Integration of transport and land-use policy will be key to rising to this challenge.

Soft policies

Car sharing and car clubs can also potentially reduce CO2 emissions, although the aggregate reduction in congestion and emissions has not been measured with an adequate degree of precision in the literature. Teleworking and teleshopping can potentially reduce congestion and also CO2 emissions. However, the evidence for this reduction is rather mixed, as it is unclear whether these measures lead to overall reductions in road transport.Eco-driving campaigns aim to inform and educate drivers in order to induce them to drive in a fuel-efficient and thus environmentally friendly way. There seems to be some consensus in the literature that eco-driving could lead to reductions in CO2 emissions of around 10 per cent.Information and education policies have often been advocated as instruments which may affect behavioural change. We find in this paper that these types of measures are necessary, but not sufficient for behavioural change. Advertising and marketing may go a long way in changing peoples’ behaviour. In California, for example, Kahn (2007) finds the “Prius” effect: the Toyota Prius is preferred by consumers relative to other similarly green vehicles, probably due to extensive marketing and celebrity endorsements. Family life changes are also found to trigger changes in behaviour ( [Goodwin, 1989] and [106]). People whose lives are being changed by some important development (birth of a child, retirement, etc) tend to respond more to changes in the relative attractiveness of different transport modes. Advertising campaigns promoting a modal shift towards public transport, for instance, may thus be more successful if targeted at people in the process of important life transitions.

Knowledge policies

Research and Development is crucial for developing sustainable and low-carbon transport for the future, and it is essential that governments provide incentives to undertake R&D, so that new low-carbon technologies in the transport sector can be demonstrated and applied at a large scale.Finally, we consider the issue of policy combination and integration. There is evidence that the combination and integration of policies can lead to positive side-effects and synergies. Policy integration is crucial in order to rise to the challenges we face in moving towards a sustainable mobility model. We conclude that classical economic policies may be successfully combined with a number of policy measures discussed in this paper in order to achieve sustainability in transport.  相似文献   
190.
面对上海市城市的新一轮发展目标,交通信息技术的应用也面临着从独立建设和实验性应用阶段到系统集成和大规模推广应用阶段的转变。上海市综合交通信息中心运用城市交通信息化战略导向下的系统分析方法,在整体设计上以信息资源规划为基础,在组织架构上以组织协同思想作为指导,在技术构成上以标准化、可靠性、先进性、开放性为原则,通过对交通信息化功能领域和应用划分、信息资源共享需求分析、组织体系结构分析和技术体系结构分析等核心技术环节的研究,提出了网络化中心和层次化支持平台构成的组织体系框架和以共用信息平台为核心的技术体系框架。并从领导机制、建设运营模式、数据标准和核心技术等几方面就其建设策略提供了有益建议,提出了分阶段实现模式。  相似文献   
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