首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   197篇
  免费   10篇
公路运输   38篇
综合类   51篇
水路运输   102篇
铁路运输   7篇
综合运输   9篇
  2021年   3篇
  2020年   6篇
  2019年   4篇
  2018年   3篇
  2017年   2篇
  2016年   2篇
  2015年   3篇
  2014年   10篇
  2013年   56篇
  2012年   12篇
  2011年   13篇
  2010年   11篇
  2009年   15篇
  2008年   17篇
  2007年   16篇
  2006年   14篇
  2005年   8篇
  2004年   1篇
  2003年   3篇
  2002年   2篇
  2001年   3篇
  2000年   1篇
  1997年   1篇
  1988年   1篇
排序方式: 共有207条查询结果,搜索用时 78 毫秒
201.
生态护坡中根系的加固机理与能力分析   总被引:2,自引:0,他引:2  
周辉  范琪 《公路》2006,(12):179-183
植物根系在岩土介质中受力的复杂性、多变性,使得确定其加固能力十分困难。根据植被护坡作用机理和应力应变模式分析,建立了加固作用力学模型,导出植物根系的抗滑力一般计算式,并推导了植物根系加固能力的计算式。  相似文献   
202.
The Spanish Strategy for Coastal Sustainability (SCS) was an initiative aimed at implementing coastal interventions under the principles of Integrated Coastal Zone Management (ICZM) and improving the state of the coast at the Spanish national level. The SCS, promoted by the Spanish Ministry of the Environment, started as a broad national strategy in 2005 and was finally delivered as a coastal planning instrument at the regional level in late 2007, designed to address coastal policies within the Spanish maritime–terrestrial public domain (MTPD). The initiative was triggered by the increasing pressure on the coastal zone and its preparation was supported by different European initiatives, first of all the European Recommendation on ICZM (413/2002/EC), while taking into consideration the future requirements of the Mediterranean Protocol on ICZM of the Barcelona Convention, signed in February 2008. Technically, the preparation of the SCS included four steps: (i) a Stakeholder Identification and Engagement process, including a stocktaking of the laws and regulations, (ii) the design of a broad Strategic Framework for the Spanish coastal zone, including a set of specific objectives and the instruments for its implementation, (iii) the signature of cooperation agreements for ICZM between the central government and the regions, and (iv) a detailed Technical Diagnosis at the local scale, designed to address future coastal interventions in the maritime–terrestrial public domain and its areas of influence. This article aims to: (i) illustrate the triggering factors of the SCS, including the Spanish coastal issues, the administrative framework at the national level, and the European and international policies addressing coastal management and (ii) illustrate the approaches and methodologies used for the preparation of the SCS, reporting the most relevant quantitative results. The article concludes that the SCS gave a strong contribution in the construction of a base of knowledge for the coastal zone and to improve coastal management practices. Despite this, complex distributions of competences still undermine the implementation of strategic interventions. In this context, the future ratification of the ICZM Protocol of the Barcelona Convention represents an opportunity to use the SCS process results and improve coastal management practices and the state of the coast.  相似文献   
203.
高速公路边坡植被恢复景观效益评价   总被引:2,自引:1,他引:1  
应用植物生长率分析、盖度—时间动态分析的方法对公路边坡试验点植被群落数量特征进行了研究,并且通过对植被生长率、盖度、地径随时间的动态变化得出植物生长变化情况。同时为了分析植被生长形成的景观效果,应用层次分析法对试验点边坡植被恢复景观效应进行了定量评价,醒目程度在景观敏感性指标中最为重要;坡度、土壤侵蚀性和植被的恢复能力在景观视觉吸收能力指标中比较重要;植被覆盖率、自然性和空间配置在景观质量指标中比较重要。  相似文献   
204.
Nearly 40 years on since its first tentative steps in North America, this article considers whether Integrated Zone Coastal Management (ICZM) in Europe has grown to maturity as a form of governance. The article summarizes the findings of recent research concerning the levels of implementation of coastal management in Europe, with particular reference to the UK experience. A research framework is used to identify the different motivations behind the social actor groups involved in coastal management. The application of this framework reveals four major findings about gaps in implementation: (1) the complexity of responsibilities at the coast continues to prevent agencies from taking a “joined-up” approach; (2) a policy vacuum is constraining implementation from national to local scales; (3) informational obstacles are significant in preventing co-ordination between science and policymakers, and between different sectors; (4) a democratic deficit is preventing implementation in the working practices of coastal stakeholders, with little opportunity in decision making for public comment or local accountability, especially offshore. The article also explores different conceptualizations of the role of coastal management and planning held across Europe, providing an analysis using the Strategic Management literature and the experience of the EU Demonstration Programme on Integrated Coastal Zone Management (1996–1999). Recent arrangements, with the availability of priming funds from the European Commission and emphasis on “pilot” and “demonstration” methods, have tended to encourage a project-based approach to ICZM that may fail to realize long-term objectives. The article seeks to present an analysis of the behaviors of scientists, academics, policymakers, and practitioners, and will be of interest to all those seeking to establish ICZM within the wider system of governance, as supported by the Commission of the European Community (2000) Communication on ICZM (COM 547). Some technical solutions are also offered from the UK experience that will be of use to coastal project officers working at national and regional levels.  相似文献   
205.
结合大东港疏港高速公路设计情况,主要从桥梁耐久性的概念设计、混凝土材料的要求、桥梁构件细部的耐久性设计、结构使用阶段的维护与检测等方面,介绍了沿海桥梁结构耐久性的设计情况。并建议在设计中多从结构构造和体系的角度提高桥梁的耐久性,改进我国桥梁防腐结构设计。  相似文献   
206.
207.
倪学伟 《中国海事》2011,(5):25-27,31
沿海、内河货物运输合同关系,在法律适用方面,以《合同法》和《民法通则》为基本标尺,以《国内水路货物运输规则》为基本规范。相关货运合同的签订,遵循《合同法》规定的要约与承诺方式,运单是运输合同的证明和承运人已经接收货物的收据。未取得《水路运输许可证》的水运企业所签的沿海、内河货物运输合同,应依法认定为有效合同,但这不影响水运行政主管机关对有关承运人追究行政责任。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号