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291.
李鑫铭  陆建  王炜 《城市交通》2009,7(4):51-57
为反映我国交通影响分析(TIA)的技术发展状况和存在的问题,对相关文献进行分析总结,从发展状况、阈值理论、预测模型、交通影响费、制度模式5个方面进行综述。研究显示,我国交通影响分析更重视交通对土地的反作用,实施对象由单体项目向区域化发展,而在交通影响分析调控土地开发强度的能力和为筹集建设资金增开渠道的作用方面尚未得到充分发挥。为了使我国交通影响分析工作更加完善,需要在4个方面进行更深入的研究:区域性交通影响分析理论、适合交通影响分析的分配算法、适合我国的交通影响费制度以及交通影响评价市场的规范化。  相似文献   
292.
针对某型试验导弹的拖曳式跟飞设备在飞行过程中受发动机高温高速尾焰影响的问题,提出了利用流体仿真计算确定尾焰辐射区域的方法。文章通过几何建模,并使用Fluent软件进行二维仿真计算,分析了固体火箭发动机尾焰辐射范围,为拖曳式设备可靠跟飞确定了危险区域,为设备自身气动设计等提供了必要的依据。  相似文献   
293.
采用RNGk-ε三维紊流模型和VOF方法,1:1几何建模,对柘林水电站左岸泄洪洞下游掺气分流墩的三维流场进行了数值模拟.在与原型观测试验对比验证的基础上,对该流场的流态、水面、流速分布和压强分布进行了分析.结果表明:流态模拟正确,水面、流速与原型观测结果均能较好吻合;联合作用下的流场,在三维涡体的形成、增强掺气效果和空化空蚀的防止等方面均明显优于无掺气分流墩的流场;三维涡体主要由两股入水主流与池内前部淹没水跃的水体相互摩擦形成;被抛向高空的水翅在下落入水时卷入大量空气,具有较深穿透力,使得波动坎及坎下区域充分掺气,从而破坏空化,防止空蚀.  相似文献   
294.
基于湍流动能倾向方程,推导出了其只含风切变和大气稳定度的简化方程.根据收集到的100例飞行中晴空颠簸的实际资料,利用环境技术应用(ETA)模式对该简化方程进行了检验.研究表明,仅利用湍流动能的产生预测晴空颠簸并不一定有效,而需要对湍流动能的产生项进行诊断.预报颠簸时,湍流动能倾向方程中的耗散项不能忽略;ETA模式的垂直分辨率和模式的设计者给定的大气稳定度对预报的准确性也有影响。  相似文献   
295.
言语失误是一种产生于口语交际过程的必然的语言现象,其形成受到认知因素、心理因素,及社会因素的影响。本文在前人研究成果的基础上,分析了言语失误的成因及其对英语口语教学的启示。  相似文献   
296.
The implementation of marine protected areas (MPAs) for fisheries management has increased recently due to the perceived role of MPAs in conserving biodiversity, increasing fish stocks, and enhancing the food security of coastal communities. However, it is unclear whether MPAs may restrict the availability of marine resources and decrease overall food security and the health of the people. In the Roviana Lagoon of the Solomon Islands, we conducted cross-comparisons of villages with MPAs and a village without an MPA to assess whether MPAs influenced local perceptions of governance, environmental change, livelihood strategies, and actual human nutrition and health. Results showed that residents of villages with effective MPAs had higher energy and protein intake than those who had no MPA or an ineffective MPA. We conclude that “no-take” marine reserves do not have adverse effects and that when MPAs are effectively sustained they may enhance local nutrition and health.  相似文献   
297.
当前我国严峻的生态危机和资源匮乏现状已对全面建设小康社会和实现中华民族的可持续发展构成了巨大威胁。我们必须摒弃发达国家走过并且正在走的以物质消耗和占有为考量标准的社会经济发展模式,并根据我国人口、资源与环境现状尽快实施社会经济发展的非物质化转型,走具有中国特色的全民富裕、全面小康的社会经济发展之路。为此,我们应首先全面提高国民的环境保护综合素质,树立适度消费的新观念;提高国家技术创新能力和自主技术依存度;下决心不惜一切代价从生产、消费源头乃至全过程保护生态环境、治理环境污染和控制资源的消耗,走非物质化的社会经济发展之路,构建资源节约型、环境友好型的和谐社会,为中华民族的可持续发展奠定生态环境和物质资源基础。  相似文献   
298.
    
This article analyzes institutional arrangements for the delivery of coastal programs through a new way of thinking about their evolution and structure. The notion of three distinct \"dimensions\" describing the phases in the evolution of institutional arrangements is introduced. The notion of dimensions is developed from conceptualizing about how institutional arrangements are diagrammed. This allows the visualization of how individual institutions and key stakeholders relate to each other in the delivery of coastal programs, how effective these relationships are, and how their relationships could be redesigned. \"Dimensional thinking\" enables the re-examination of existing institutional design of coastal programs and how these can evolve to meet the challenges of the new millennium. It is concluded that institutional arrangements have grown from a single dimensional view, where institutions (mainly governmental) delivered programs in isolation, through to the present second dimension where agency programs are managed through coordinating bodies and through coastal management plans. It is argued that a third dimension of institutional arrangements, one that recognizes and embraces the rapid pace of change in this century, will be needed that is aligned by themes rather than by organizational structure. To illustrate a third dimension a visualization tool is developed drawing from management cybernetics. It recognizes the increasing importance of formal and informal networks in relation to traditional modernist hierarchical management by recognizing multiple stakeholders (government at all levels, industry, advocacy groups, conservation interests, and the broader community) and their degree of mutual dependence. Dimensional thinking has the potential to institutionalize the interaction between these multiple stakeholders to ensure the effective delivery of coastal programs in the new millennium. A single answer to what the third dimension of coastal management program evolution should include is not presented. Rather, an approach is presented that allows coastal managers to move forward in the debate on redesigning coastal programs to meet today's complex suite of issues, values, and interests. An experimental case study from Western Australia is used to illustrate the potential application of the dimensional thinking to coastal management institutional design in that State's coastal program.  相似文献   
299.
    
Governments around the world are adopting inclusive growth agendas. The ambition to align economic growth ambitions with broader-based social benefits is increasingly embraced by corporations to limit the ‘negative externalities’ and enhance the ‘positive externalities’ of their operations. Therefore, micro-level corporate strategies and macro-level national ambitions meet at the meso-level of networks and clusters. This requires societal spheres to collaborate and search for alternative governance constellations. In this discourse, port development is only recently receiving attention. In March 2018, ports around the world signed the World Ports Sustainability Program declaration, which aims to contribute to the sustainable development goals (SDGs), whilst a number of national port (master) plans have started to include social along with environmental standards. Extant studies on partnering and stakeholder inclusion in port development are proliferating but are primarily aimed at environmental rather than social (inclusion) issues. This paper adopts an exploratory research design to consider conditions for inclusive port development. A novel taxonomy considers port development as a driver for inclusive growth, where partnerships are the missing link between micro-level business strategies and macro-level effects in the port region and economy at large. This paper shows the first findings and delineates areas for further research.  相似文献   
300.
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