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961.
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   
962.
后危机时代南通船舶产业发展战略研究   总被引:1,自引:1,他引:0  
文章分析了在金融危机对我国船舶工业带来巨大冲击的背景下,作为南通市支柱产业的船舶工业的发展现状.重点论述了后危机时代,南通船舶工业保持和提高竞争力,持续发展的具体对策.  相似文献   
963.
就船舶工业目前面临的形势,论述了加快科技发展、加强自主创新来应对挑战的战略思路,提出了实现可持续发展的根本举措,强调落实开创自主创新新局面的几项重要工作。  相似文献   
964.
回顾了我国船舶工业20年来的发展历程,介绍了近年来我国在船舶设计水平和船型开发优化方面取得的喜人成绩。但与造船业发达国家或地区相比,我国船舶设计、船型研发方面仍有不小差距。针对这些差距,提出了加快3大主流船型的优化和换代开发、高新技术船舶和海洋工程装备开发的发展思路和提高我国船舶设计水平的措施和建议。  相似文献   
965.
高频地波雷达发展动向与分析   总被引:1,自引:1,他引:0  
高频地波雷达在海洋领域发挥着不可替代的作用。文章分析了高频地波雷达的发展动向。  相似文献   
966.
陈志刚  姜军  李启元 《舰船电子工程》2010,30(2):132-134,143
IETM不仅实现了技术手册的数字化和智能化,而且它遵循相关标准,从根本上为实现数据的互操作和共享,实现数据的网络集成提供了可能。随着装备信息化程度日益提高,对IETM通用的制作编辑、发布和运行平台的需求日益突出。目前,有关IETM通用开发平台设计的文章比较少,针对该问题,在分析IETM创作过程和功能需求的基础上,提出了IETM开发平台的基本组成和工作流程,并重点对其信息数据结构给予定义,为IETM开发平台的软件实现奠定了基础。  相似文献   
967.
轨道交通车辆基地用地规划的选址和用地规模对综合开发的可行性和经济性影响显著。通过对车辆基地综合开发的建设周期、建设成本和开发强度分析,发现各个城市的落实程度和效果不一,整体出现综合利用比例低、综合绩效不理想等现象。以北京、南宁等城市为例,对典型车辆基地的规划布局和用地规模进行研究,车辆基地选址普遍位于非生活区,周边缺乏配套基础设施;用地规模受节地模式的影响,导致地块狭长、缺少腹地。研究结果表明在多样化的车辆基地用地程序下,重大项目和单独选址的用地模式导致车辆基地普遍采用节地模式,从而削弱综合利用结构转换层落地的可能性,缺少腹地限制了联合开发与综合平衡的可能性;由于在选址阶段考虑土地收储成本,导致位于城市边缘地区的车辆基地易受地价和周边开发成熟度的制约,影响综合利用率和上盖开发业态。基于此,对车辆基地在功能定位、选址标准、用地程序、规划编制等方面存在的缺失和错位提出改进建议。  相似文献   
968.
从规划和实施效果两个层面,研究南京轨道交通与城市发展间的相互影响。首先,通过梳理南京历版轨道交通线网规划与城市总体规划的互动关系,阐述各时期、不同城市形态下城市空间发展战略对轨道交通线网布局的需求,显示轨道交通“依据总规、支持总规”的属性;然后,通过剖析城市轨道交通对城市空间发展的影响,佐证轨道交通对城市发展的反作用,展现轨道交通“超越总规、回归总规”的作用。南京地铁在引领城市空间拓展、支持中心体系构建、促进城市立体化和集约化建设、引导城市人口与产业分布等方面发挥了重要作用。通过对轨道交通与城市空间发展互动中的问题展开思考,提出下阶段轨道交通发展策略:合理响应片区发展需求、强化轨道交通与城市空间协调建设及科学引领都市圈一体化发展等。  相似文献   
969.
针对我国城市以公共交通为导向的开发(transit-oriented development,TOD)实施过程中出现的交通站点与 空间形态发展耦合不足、步行环境欠佳、功能适配性存疑等问题,以广州珠江新城、公园前和长寿路 3 个地铁站 点为例,借助空间句法比较分析站域空间网络的组构特性及其与站点布置、步行人流分布、建设强度及功能布局 等的关联,考察 TOD 模式下站域空间形态发展的特征及规律,并对存在的问题进行厘定。结果显示:珠江新城 站域街区网格化程度不足,站点与空间组构耦合互动不足;公园前站域街道网络可达性强,集聚人群活动效应明 显,但当前功能布局与空间组构存在不匹配现象;长寿路站域背景网络结构连续均匀,对步行交通出行有利,但 商业功能布局对小尺度组构所牵引的人流利用不足。因此,我国未来轨道交通站域建设应关注空间组构对人车流 的基础决定力量,提高交通站点、功能布局与空间网络形态之间的协同。  相似文献   
970.
随着城市建设工程的持续增加,城市地下空间开发和市政设施建设产生的交叉也越来越多,许多基坑工程会在周边市政道路已经建成的条件下进行施工,基坑施工对既有市政道路产生一定的沉降影响,市政道路产生附加变形和附加应力降低了沥青路面的疲劳寿命。针对宁波市某基坑工程施工对近接市政道路的影响为工程背景,基于Plaxis数值模拟平台采用考虑小刚度的土体硬化本构模型,分析基坑的施工和简化的交通荷载对市政道路的受力变形的影响。在此基础上,采用蒙特卡洛法和数值模拟结果对道路结构层厚度进行随机选取,以沉降量为控制指标计算出疲劳寿命对该市政道路结构层给出了优化结果。  相似文献   
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