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191.
Discussions of how changes in exchange rates impact on international airlines tend to be ambivalent. In this paper, it is shown that the relative cost competitiveness of an international airline will decline when there is an exchange rate appreciation in its home country - as will be the case for other tradable goods and services. The extent to which this happens depends on which countries the prices of the inputs are set in and also on which countries' airlines it is closely competing with. The impact is greater if there is an appreciation relative to those countries whose airlines the home airlines are closely competing with. In the trade literature, this is recognised in the Trade Weighted Index of exchange rates, which weights exchanges rates according to their importance in a country's trade flows. In this paper, an Airline Trade Weighted Index is developed - the weights for this index depend on airline traffic and revenues on routes to and from a country. The ATWI is calculated for Australian international airlines, and it indicates that there has been a significant loss of competitiveness in recent years, due to the appreciation of the Australian dollar relative to currencies of key airline competitor countries.  相似文献   
192.
193.
Peter 《世界汽车》2007,(1):46-49
福特野马Shelby GT500继承了原型车全面高性能的传统,正是这种特质使GT500的原型赛车称雄于世界各地的赛场和公路比赛。  相似文献   
194.
Peter 《世界汽车》2007,(1):58-59
雷诺旗下主力产品Megane自从发表新一代车型以来.凭借着许多独特的设计手法,不但赢得全球车迷们的目光,还确立了这家法国车厂新时代的家族造型风格,而近年来雷诺在F1赛场上的优异表现.更让其拥有鲜明的运动形象.除了国人较为熟悉的MeganeRS225之外.原厂在日前也发表了同样具有运动取向的MeganeGT.以巩固其在市场上的地位。该款车定位介于一般版本的Megane以及由雷诺运动部门所开发的产品之间。同时.为了满足客户的不同需求.MeganeGT将同时有三门和五门两种车型。  相似文献   
195.
Peter 《世界汽车》2007,(3):68-70
维拉克斯是现代汽车全新打造的豪华SUV。维拉克斯从2004年7月开始研发,历时26个月耗资2亿2200万美元,以时尚动感的设计,大量的尖端技术,最完备的安全系统和各种人性化的便利配置融为一体。并寄予着提升现代汽车品牌的全新产品。  相似文献   
196.
Abstract

This paper documents some thoughts on the reform agenda in public transit that is occurring throughout the world. The specific focus is on a growing commitment to competitive regulation through competitive tendering, and the efforts by a few governments (notably in Australia) to take control of the tangible assets used by private operators as a mechanism to exercise the opportunity, if so taken, to put services out to competitive tender. The paper reviews the theoretical arguments and empirical evidence on contracting regimes and asset ownership, and the role that government and the operator might play in a setting in which building trusting and collaborative partnerships has merit in delivering services that are in the main funded from the public purse.  相似文献   
197.
Urban public transport energy use is determined largely by the weight of the vehicle, and frequency of intermediate stops, imposing repeated acceleration/steady running/braking cycles, in which much of the kinetic energy is dissipated. Energy consumed for the same capacity and vehicle performance may be reduced by coasting, cutting vehicle weight, and use of regenerative braking, on electrically‐powered systems, to convert the otherwise wasted braking energy into useful form. Particular attention is paid to the last‐named, identifying results of past experience and recent simulations. Practical constraints limiting the amount of energy actually recovered are discussed, including proportion of vehicle weight braked electrically, receptivity of the supply system, stop spacing and number of vehicles operated simultaneously. Reference is also made to battery vehicles and flywheel energy storage.

It is suggested that considerable scope exists in urban electric rail operation for reduced energy consumption, as existing fleets are replaced by lighter weight vehicles, fitted for regenerative braking. Further savings may come from use of inverter equipment. Rate of fleet renewal may be an important factor. Buses are already much more energy efficient, and dramatic gains are unlikely. However, there is some scope for use of flywheel energy storage, and regenerative braking on trolleybuses.  相似文献   
198.
Rollover of heavy vehicle is an important road safety problem world-wide. Although rollovers are relatively rare events, they are usually deadly accidents when they occur. The roll stability loss is the main cause of rollover accidents in which heavy vehicles are involved. In order to improve the roll stability, most of modern heavy vehicles are equipped with passive anti-roll bars to reduce roll motion during cornering or riding on uneven roads. However these may be not sufficient to overcome critical situations. This paper introduces the active anti-roll bars made of four electronic servo-valve hydraulic actuators, which are modelled and integrated in a yaw-roll model of a single unit heavy vehicle. The control signal is the current entering the electronic servo-valve and the output is the force generated by the hydraulic actuator. The active control design is achieved solving a linear optimal control problem based on the linear quadratic regulator (LQR) approach. A comparison of several LQR controllers is provided to allow for tackling the considered multi-objective problems. Simulation results in frequency and time domains show that the use of two active anti-roll bars (front and rear axles) drastically improves the roll stability of the single unit heavy vehicle compared with the passive anti-roll bar.  相似文献   
199.
While some countries have made progress in encouraging more sustainable transport and travel patterns, there are limits as to how far this can be taken simply by looking at the decarbonisation of transport systems, since most travel is a derived demand and hence is strongly influenced by decisions taken by public and private sector agencies in different sectors. The paper first identifies some of the major non-transport sector influences on different aspects of travel behaviour. It then looks in more detail at changing patterns of grocery shopping over the last half century, and how these changes have been associated with new non-transport technologies and accompanying developments in business and social practices. Next, a simple visual spreadsheet tool is presented, that has been used by agencies to explore the main cross sector impacts (both positive and negative) of their major location and operating decisions. Finally, the paper proposes three ways in which cross sector synergies can be encouraged: (i) by giving each sector or major organisation responsibility for all CO2 emissions associated with its activities, including those generated by the travel of its staff, customers, suppliers, etc.; (ii) by making major policy making within government a cross sector activity; and (iii) by developing a common, cross sector appraisal methodology for assessing the full range of impacts of policy proposals.  相似文献   
200.
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