全文获取类型
收费全文 | 621篇 |
免费 | 13篇 |
专业分类
公路运输 | 133篇 |
综合类 | 49篇 |
水路运输 | 71篇 |
铁路运输 | 298篇 |
综合运输 | 83篇 |
出版年
2024年 | 1篇 |
2022年 | 6篇 |
2021年 | 15篇 |
2020年 | 11篇 |
2019年 | 9篇 |
2018年 | 7篇 |
2017年 | 16篇 |
2016年 | 17篇 |
2015年 | 27篇 |
2014年 | 32篇 |
2013年 | 29篇 |
2012年 | 51篇 |
2011年 | 53篇 |
2010年 | 51篇 |
2009年 | 38篇 |
2008年 | 37篇 |
2007年 | 50篇 |
2006年 | 41篇 |
2005年 | 32篇 |
2004年 | 30篇 |
2003年 | 30篇 |
2002年 | 12篇 |
2001年 | 4篇 |
2000年 | 6篇 |
1999年 | 2篇 |
1997年 | 5篇 |
1996年 | 5篇 |
1995年 | 5篇 |
1994年 | 5篇 |
1993年 | 4篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
排序方式: 共有634条查询结果,搜索用时 390 毫秒
31.
本文介绍了当今世界上典型的中大型客滚渡船传统的线型设计方法和推进系统,以及近年来针对大型客滚渡船研发的新推进理念和方法。详细介绍这些新的推进理念,并将其与传统的方式进行比较,对将来的实际应用提出了建议。 相似文献
32.
结合我国国情,客运专线拟采用多种速度动车组混合运行的运输组织模式,通过分析客运专线运输市场需求价格弹性,探讨了按淡、旺季对客运专线分市场来实施差别价格策略的合理性与可行性。通过分析表明,在一定条件下实施季节性差别定价法能增加客运专线运营企业利润,提高经济效益。 相似文献
33.
The present paper deals with timetable optimisation from the perspective of minimising the waiting time experienced by passengers when transferring either to or from a bus. Due to its inherent complexity, this bi-level minimisation problem is extremely difficult to solve mathematically, since timetable optimisation is a non-linear non-convex mixed integer problem, with passenger flows defined by the route choice model, whereas the route choice model is a non-linear non-continuous mapping of the timetable. Therefore, a heuristic solution approach is developed in this paper, based on the idea of varying and optimising the offset of the bus lines. Varying the offset for a bus line impacts the waiting time passengers experience at any transfer stop on the bus line.In the bi-level timetable optimisation problem, the lower level is a transit assignment calculation yielding passengers’ route choice. This is used as weight when minimising waiting time by applying a Tabu Search algorithm to adapt the offset values for bus lines. The updated timetable then serves as input in the following transit assignment calculation. The process continues until convergence.The heuristic solution approach was applied on the large-scale public transport network in Denmark. The timetable optimisation approach yielded a yearly reduction in weighted waiting time equivalent to approximately 45 million Danish kroner (9 million USD). 相似文献
34.
In this paper, we propose an agent-based simulation approach that is capable of simulating the flow of passengers on board buses and at bus stops. The intention is that it will be applied during vehicle development to analyze how vehicle design affects passenger flow, and thus also how it affects system performance such as dwell time. In turn, this could aid the developers in making design decisions early in the development process. Besides introducing the simulation tool itself, the paper explores the realism of the data generated by the tool. A number of passenger flow experiments featuring a full-scale bus mockup and 50 participants were carried out. The setup of these experiments mirrored a number of ‘bus journeys’ (regarding vehicle design, number of passengers boarding/alighting at each stop and so on) that had previously been simulated using the simulation tool. When the data from the simulations were compared with the data from the passenger flow experiments, it could be concluded that the tool is indeed able to generate realistic passenger flows, although with some errors when a large number of passengers board/alight. The simulated dwell times were rationally affected by the tested bus layout aspects. It was concluded that the tool makes it possible to evaluate how variations in bus layouts affect passenger flow, providing data of sufficiently high quality to be useful in early phases of vehicle design. 相似文献
35.
36.
奥迪100轿车后螺旋弹簧的可靠性设计 总被引:6,自引:0,他引:6
本文介绍了奥迪100桥车后螺旋弹簧的可靠性设计方法。在基本随机变量的概率特性已知的情况下,使用二阶矩技术对弹簧的可靠性进行设计,所编制的计算机程序可以迅速准确地得到弹簧的可靠性设计参数。 相似文献
37.
作者考察了英国客运交通的发展情况,文章结合我国及广西的实际情况,就如何吸收和借鉴英国有益的经验和做法,提出了加快道路运输发展的措施和建议。 相似文献
38.
Avishai Ceder 《Transportation》2006,33(2):133-152
A predominant observation in Hong Kong is the continuous loss in ferry patronage. There are two main reasons for this: poor
level-of-service and better competitors. New roads, bridges, and tunnels are serving the buses, and to some extent the railways;
whereas the investment in ferry terminals is relatively at a lower level. On the one hand, there is no need to promote the
ferries in a free market environment; but on the other hand, the ferries have the best safety record, can only relieve some
traffic congestion and need water access that is one of the characteristics of Hong Kong. The goal of this paper is to design
a planning approach combined with an evaluation procedure on how to make the best use of the existing water and pier resources
in Hong Kong through the provision of commercially viable ferry services. The approach used covers the impact of future developments
planning up to 2006 comprising all public transport modes in Hong Kong (heavy rail, metro, bus, and ferry). The planning tool
is based on a newly developed multi-objective evaluation method in order to assess the ferry routes with scientific, practical,
and simplified analyses for future use. This assessment is applied to the existing ferry routes and candidate routes and can
also be carried out on an individual route basis or on a given set of routes. The objective functions set forth analytically
in the evaluation method take into account the interests of the three participants: the passengers, the operators and the
government. The proposed ferry network design formulation and the suggested new ferry routes will have a positive impact on
changing the ferry system’s image in Hong Kong. 相似文献
39.
由PSA集团和雷诺公司共同设计的AL4自动变速器,装备于雪铁龙Xantia中档轿车上。该变速器具有智能化程度高、换挡品质好、扭矩覆盖面大及结构紧凑等特点。该变速器采用带锁止离合器的扁平型三元件液力变矩器,行星齿轮变速机构采用的是CR-CR(辛普森2型)机构,换挡操纵机构采用推拉软轴式操纵机构。 相似文献
40.