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   300篇
  免费   4篇
公路运输   63篇
综合类   4篇
水路运输   110篇
铁路运输   6篇
综合运输   121篇
  2022年   1篇
  2019年   5篇
  2018年   3篇
  2017年   12篇
  2016年   7篇
  2015年   6篇
  2014年   3篇
  2013年   58篇
  2012年   4篇
  2011年   6篇
  2010年   19篇
  2009年   21篇
  2008年   22篇
  2007年   23篇
  2006年   12篇
  2005年   6篇
  2004年   6篇
  2003年   4篇
  2002年   5篇
  2001年   2篇
  2000年   4篇
  1999年   3篇
  1998年   3篇
  1997年   3篇
  1996年   7篇
  1995年   6篇
  1994年   1篇
  1993年   6篇
  1992年   4篇
  1991年   4篇
  1990年   2篇
  1988年   2篇
  1987年   1篇
  1986年   3篇
  1985年   1篇
  1983年   1篇
  1982年   2篇
  1981年   4篇
  1979年   4篇
  1978年   2篇
  1977年   2篇
  1976年   7篇
  1975年   4篇
  1974年   1篇
  1973年   1篇
  1972年   1篇
排序方式: 共有304条查询结果,搜索用时 78 毫秒
301.
The paper compares the pedagogical advantages of two simulation types used for training verbal maritime communication. It tests the hypothesis that “low-fi” simulation using online web conference software, specifically ‘chat’ or messaging, is a valid complementary tool for the instruction of Maritime English and full-mission simulation. Based on a series of exercises involving multi-national and multi-lingual students, various linguistic patterns are determined and compared to audio recordings of full-mission simulation. Probability of superiority effect sizes is computed to quantify the observed effects. The findings corroborate the proximity of language patterns found in low-fi and full-mission simulation. Pedagogical implications are discussed, and future research possibilities are outlined.  相似文献   
302.
Wide-ranging and ambitious proposals for the comprehensive transformation of public transport systems in major South African cities, including Cape Town, have now been in play for a decade or more since the country’s post-apartheid transition. To date, progress in implementing such proposals has been, at best, much delayed and, in Cape Town, appears to have stalled, and may now be significantly compromised. This paper draws on aspects of the concept of regulatory cycles in the bus transport sector to explore some of the key factors which have given rise to this situation, focusing primarily on obstacles embedded in the present institutional framework which governs the provision of road-based public transport in the city. It specifically identifies difficulties in establishing an appropriately mandated and resourced agency at the local level to drive forward the transformation project and the sustained opposition of existing, largely ‘self-regulated’ minibus-taxi operators as key factors which have obstructed the introduction of the proposed regime of ‘regulated competition’. A tentative conclusion is offered to the effect that perhaps a partial or ‘hybrid’ transformation of the public transport system may be the best - and, indeed, possibly the most appropriate - outcome of the transformation process that can be anticipated under the present and foreseeable future circumstances prevailing in the city.  相似文献   
303.
Two-sided markets are characterised by the presence of an intermediary and two groups of end-users. In the cruise market, cruise lines may play the role of intermediaries to connect the two end-users, viz. cruise passengers and cruise ports. Our research explored whether the cruise industry can be regarded as a two-sided market, starting with a theoretical modelling. The findings show that cruise lines might be hybrid intermediaries, selling their own ship-based products and services, while offering also a platform to enable the transaction between cruise passengers and cruise ports. This particular business model of a quasi-two-sided market is also reflected in the pricing scheme of cruise industry, whereby cruise ports charge an entry fee from cruise lines and port dues from cruise passengers. We illustrate an empirical analysis on the basis of the cruise market in Japan, and it provides a preliminary clue that the behaviours of cruise ports and cruise lines are consistent with our theoretical framework. The results are not convincingly significant due to data limitations, hence, the concept of a ‘two-sided market’ in the cruise industry call for further empirical research.  相似文献   
304.
This paper describes a connected-vehicle-based system architecture which can provide more precise and comprehensive information on bus movements and passenger status. Then a dynamic control method is proposed using connected vehicle data. Traditionally, the bus bunching problem has been formulated into one of two types of optimization problem. The first uses total passenger time cost as the objective function and capacity, safe headway, and other factors as constraints. Due to the large number of scenarios considered, this type of framework is inefficient for real-time implementation. The other type uses headway adherence as the objective and applies a feedback control framework to minimize headway variations. Due to the simplicity in the formulation and solution algorithms, the headway-based models are more suitable for real-time transit operations. However, the headway-based feedback control framework proposed in the literature still assumes homogeneous conditions at all bus stations, and does not consider restricting passenger loads within the capacity constraints. In this paper, a dynamic control framework is proposed to improve not only headway adherence but also maintain the stability of passenger load within bus capacity in both homogenous and heterogeneous situations at bus stations. The study provides the stability conditions for optimal control with heterogeneous bus conditions and derives optimal control strategies to minimize passenger transit cost while maintaining vehicle loading within capacity constraints. The proposed model is validated with a numerical analysis and case study based on field data collected in Chengdu, China. The results show that the proposed model performs well on high-demand bus routes.  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