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   377篇
  免费   8篇
公路运输   26篇
综合类   16篇
水路运输   150篇
铁路运输   6篇
综合运输   187篇
  2022年   3篇
  2021年   2篇
  2020年   3篇
  2019年   10篇
  2018年   11篇
  2017年   13篇
  2016年   11篇
  2015年   4篇
  2014年   9篇
  2013年   93篇
  2012年   15篇
  2011年   11篇
  2010年   24篇
  2009年   21篇
  2008年   13篇
  2007年   12篇
  2006年   8篇
  2005年   10篇
  2004年   3篇
  2003年   2篇
  2002年   13篇
  2001年   2篇
  2000年   7篇
  1999年   3篇
  1998年   5篇
  1997年   5篇
  1996年   7篇
  1995年   4篇
  1994年   5篇
  1993年   5篇
  1992年   4篇
  1991年   4篇
  1989年   2篇
  1988年   1篇
  1987年   5篇
  1986年   1篇
  1985年   3篇
  1983年   3篇
  1982年   3篇
  1981年   2篇
  1980年   1篇
  1979年   2篇
  1978年   5篇
  1977年   1篇
  1975年   5篇
  1974年   3篇
  1973年   5篇
  1972年   1篇
排序方式: 共有385条查询结果,搜索用时 0 毫秒
271.
272.
In light of increasingly depleted coastal resources under the current management structure, this article explores the institutional arrangements that would be necessary in Fiji to create and implement a viable comanagement regime that would devolve some of the responsibility for management to the communities. Based on the literature concerning institutions for comanagement and the present situation and the institutional management structure in Fiji, it is recommended that government act as the catalyst by putting forth an enabling policy framework for comanagement that formally recognizes customary marine tenure. Such a policy should allow communities to derive bylaws from local rules, through shared management and technical assistance at the provincial level. At this same administrative level, planning units are recommended to coordinate government management of activities in the coastal zone.  相似文献   
273.
Marine food web dynamics are determined by interactions within and between species and between species and their environment. Global change directly affects abiotic conditions and living organisms, impinging on all trophic levels in food webs. Different groups of marine researchers traditionally study different aspects of these changes. However, over medium to long time scales perturbations affecting food webs need to be considered across the full range from nutrients to top predators. Studies of end-to-end marine food webs not only span organism sizes and trophic levels, but should also help align multidisciplinary research to common goals and perspectives. Topics are described that bridge disciplinary gaps and are needed to develop new understanding of the reciprocal impacts of global change on marine food webs and ocean biogeochemistry. These include (1) the effects of nutrients on biomass and production, (2) the effects of varying element ratios on food web structure and food quality, (3) bulk flows of energy and material in food webs and their efficiencies of transfer, (4) the ecological effects of species richness and the roles of microbial organisms, (5) the role of feeding behaviour in food web dynamics and trophic controls, (6) the spatial dynamics of communities and links between different food webs, (7) the combined effects of body size and behaviour in determining dynamics of food webs, and (8) the extent to which the ability of marine organisms (and communities) to adapt will influence food web dynamics. An overriding issue that influences all topics concerns the time and space scales of ecosystem variability. Threads link different nodes of information among various topics, emphasizing the importance of tackling food web studies with a variety of modelling approaches and through a combination of field and experimental studies with a strong comparative approach.  相似文献   
274.
中国传统文化价值观讲究“国家”、“家庭”、“父母”、“师长”优先于个人.本研究以“美国人眼中的中国”大型国际调研数据为基础,通过对涉及中国传统文化价值观的8个问题与人口学属性(性别、年龄、受教育程度、收入、种族、党派归属)和媒介接触频率进行回归分析后发现:受教育程度高者及黑人/非洲裔美国民众对中国传统文化价值观的认同度相对较低,而保守党人士及较多通过广播收听新闻的美国民众对中国传统文化价值观的认同度较高.由此导出,在中国国际形象塑造和对美文化交流中,应该注重“分众”传播.  相似文献   
275.
ROAD KILL CARPET     
这地毯血腥了点,其实它很有爱心。由于出品方是设计了树枝U盘(Wooden USB Stick)的荷兰Studio OOOMS,我很相信OOOMS这次又是在发挥对自然的热爱——地毯上那只血肉模糊的狐狸,是设定为被飞驰的汽车谋杀而死。那么你不妨将这地毯送给你粗心大意而又迷恋疾速驾驶的朋友,提示他以后通过野生动物栖息地的时候,将车速放慢些,眼睛睁大些。当然,如果他听取了意见,你也不必反对他拿狐狸尸体的那部分当做枕头,躺在这地毯上打盹。2009年春季上市,纯手工,纯羊毛制造。尺寸:165×240cm/65×94.5inch  相似文献   
276.
法国南特第一列Incentro轻轨列车   总被引:1,自引:0,他引:1  
简要介绍了法国南特轻轨车辆的设计思路、结构特点和模块化设计。  相似文献   
277.
Wu  Chenyang  Le Vine  Scott  Sivakumar  Aruna  Polak  John 《Transportation》2022,49(2):679-702
Transportation - Free-floating carsharing (FFCS) systems are characterised by volatile fleet distribution as well as customers’ heterogeneous price sensitivity and spatiotemporal flexibility....  相似文献   
278.
Congestion of urban transportation systems results from an equilibrium of location and travel choices with generalized travel costs which increase with vehicle flows as well as other factors. The use of network equilibrium concepts in analyzing urban policies and evaluating alternative plans is examined. Issues arising in the use of network equilibrium models are described, and formulations of urban network prediction and design models are explored.  相似文献   
279.
Rosenfield  Adam  Attanucci  John P.  Zhao  Jinhua 《Transportation》2020,47(4):1907-1932
Transportation - This paper presents a trial aimed at reducing parking demand at a large urban employer through an informational campaign and monetary incentives. A 6-week randomized controlled...  相似文献   
280.
Beck  Matthew J.  Rose  John M. 《Transportation》2019,46(4):1195-1213

While the study of choices focuses primarily on the individual decision maker, there is growing interest in the examination of the choices made by groups. Much of the research into the choices of multiple decision makers has revealed that they differ significantly to those of individuals. In this study of household vehicle choice we similarly compare individual choices to group choices and support this finding. Consequently any research into choices that involve groups should acquire data from those groups. In this paper we show how this may be done via an interactive agency choice experiment which makes the individual preferences endogenous to the choice of the group. This method and many like it, however, involve significant time, incentive and administrative costs that often make such studies prohibitive. In this paper we also compare another class of model, minimum information group inference, which is designed to provide an overview of the likely group choice and while not having the specificity of detail as other methods, has the advantage of being much easier and cheaper to implement and is perhaps the only methodology that can be employed when it is not feasible for respondents to interact. We find that this method is a good approximation of group choice, mapping the preference space over which group choice is likely to be located.

  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