全文获取类型
收费全文 | 2974篇 |
免费 | 19篇 |
专业分类
公路运输 | 977篇 |
综合类 | 104篇 |
水路运输 | 940篇 |
铁路运输 | 89篇 |
综合运输 | 883篇 |
出版年
2023年 | 14篇 |
2022年 | 53篇 |
2021年 | 27篇 |
2020年 | 22篇 |
2019年 | 29篇 |
2018年 | 88篇 |
2017年 | 86篇 |
2016年 | 122篇 |
2015年 | 37篇 |
2014年 | 110篇 |
2013年 | 456篇 |
2012年 | 158篇 |
2011年 | 165篇 |
2010年 | 137篇 |
2009年 | 156篇 |
2008年 | 141篇 |
2007年 | 91篇 |
2006年 | 64篇 |
2005年 | 62篇 |
2004年 | 46篇 |
2003年 | 45篇 |
2002年 | 44篇 |
2001年 | 41篇 |
2000年 | 52篇 |
1999年 | 35篇 |
1998年 | 45篇 |
1997年 | 49篇 |
1996年 | 50篇 |
1995年 | 71篇 |
1994年 | 27篇 |
1993年 | 35篇 |
1992年 | 29篇 |
1991年 | 24篇 |
1990年 | 18篇 |
1989年 | 14篇 |
1988年 | 20篇 |
1987年 | 21篇 |
1986年 | 16篇 |
1985年 | 25篇 |
1984年 | 25篇 |
1983年 | 18篇 |
1982年 | 25篇 |
1981年 | 32篇 |
1980年 | 28篇 |
1979年 | 40篇 |
1978年 | 21篇 |
1977年 | 21篇 |
1976年 | 11篇 |
1975年 | 18篇 |
1974年 | 15篇 |
排序方式: 共有2993条查询结果,搜索用时 62 毫秒
151.
The Sydney Olympics held in September 2000 provided an opportunity to monitor the planning of transport provision for the world's greatest sporting spectacular. As the single largest major event, the pressures on a city's transport system are enormous, as witnessed by the previous Games in Atlanta and Barcelona. This paper takes a value-chain approach to assess transport performance as a crucial element in the delivery of the Sydney Olympic Games. We begin with a brief overview of strategic value, highlighting some generic aspects of value chains followed by the transport delivery system that came to the fore as significant 'drivers' in the value chain. This is followed by a summary of the effectiveness of the buses, trains, taxis, roads and the airport. A more detailed look is provided of the private bus sector where the problems leading up the opening of the Games received a great deal of media attention. The paper concludes with two stories, one good, one not so good, about transport and the Olympic Games. 相似文献
152.
M. Hadi Baaj 《运输评论》2013,33(1):103-113
The Lebanese Council of Ministers has recently endorsed a plan for the reform and organization of the Land Public Transport Sector (LPTS). The plan implies a new role for the government: it would cease being just a loss-making service provider and become the planner and regulator of the sector under a new strategy. The strategy would aim at creating the enabling environment and conditions that allow and ensure the existence of sufficient, affordable and efficient transport services provided by several private-sector operators functioning under competitive conditions. Thus, the existing autonomous Railway and Public Transport Authority (RPTA) will be restructured to serve as the effective regulator, its bus operations will be corporatized (for possible eventual privatization), and all existing private sector service providers will be regulated. Following a brief overview of the problems of the sector and the components of the reform and organization plan, this paper focuses on developing options for the restructuring of the RPTA to carry out its new role. 相似文献
153.
Peter J. Wilcoxen 《Coastal management》2013,41(3):173-191
Abstract One of the consequences of sea level rise resulting from the greenhouse effect is increased coastal erosion. This article discusses a model of erosion that can be used to estimate the response of beaches to sea level rise. The model is applied to Ocean Beach, California, with particular attention to the consequences of accelerated erosion for the San Francisco Westside Sewer Transport. Results obtained show that erosion produced by accelerated sea level rise could cause substantial damage to the structure. Large expenditures on beach nourishment will be required to protect the transport and the recreational value of the beach. 相似文献
154.
155.
Galal M. Said 《运输评论》2013,33(4):321-348
Abstract Kuwait is a relatively small country located at the top of the Arabian Gulf with population in 1980 amounting to 1.355 millions. Kuwait occupies an area of approximately 17 800 square kilometres. Kuwait's main source of national income is oil export. Income from oil export and other sources has resulted in Kuwait having the highest per capita income in the world. Consequently vehicle ownership is very high and traffic is ever growing and extending. Kuwait is self‐sufficient in only a few commodities and has a shortage of local labour. This means that transport has a fundamental role to play at the national and international level for the development of Kuwait's economy. This paper provides a brief statement of transport in Kuwait. It starts by describing Kuwait's national setting and touches on the economic and social aspects in Kuwait that have an influence on transport patterns and needs. It describes the national transport system and covers road, air, rail and ports. Urban development planning in Kuwait is described and issues related to stages of urban development planning. The Kuwait City Master Plan and new town initiatives are presented. The urban transport system in Kuwait Metropolitan Area is described. In particular the characteristics of the urban road network and public transport facilities are outlined along with recent transport planning studies and new initiatives in the urban transport system. The paper ends with a statement on organizations involved in the transport sector in Kuwait and a note on transport finance. 相似文献
156.
Derek J. McGlashan 《Coastal management》2013,41(3):221-236
This article considers the issue of economic development as a component of coastal management initiatives in developed countries, focusing on the Forth Estuary Forum as a case study. The evolution of coastal management into integrated coastal management is briefly considered, as is the context of the Scottish coastal management system and a brief discussion of the variations between the different legal systems within the UK. The current hurdles to economic development and the views of developers and economic agencies being considered in the coastal management process itself are highlighted, illustrating the process of integration and the current voluntary regime in the UK, particularly in the Forth Estuary Forum. The article concludes that economic development issues must be taken seriously if coastal management is to be integrated and inclusive. 相似文献
157.
158.
Standardized and free-format questionnaires on the state of coastal management were fielded to coastal management practitioners during three workshops and a national feedback and recommendation workshop. The most commonly cited responses were identified for each of 13 political regions and overall trends were identified. Management frameworks frequently included research, community organizing, education, livelihood, resource enhancement, resource protection, regulation, and networking components. Gender issues, documentation, and infrastructure investment were rare. The most commonly perceived environmental problem was illegal/ destructive fishing and its associated overfishing and low fish catch. The most commonly cited socioeconomic problem was the inadequacy of law enforcement. The best monitored variables were usually those related to environmental management: status and change of habitats, resources, and degree of enforcement/patrolling activities. The most common nonregulatory enhancement, aside from environmental education (which is the most popular), was mangrove reforestation. In terms of regulations, the majority of the respondents have reportedly formulated an integrated coastal management plan. In practice, regulating destructive and illegal fishing practices and then the establishment of fish sanctuaries are the next most implemented. The most popular quality-of-life enhancement strategies focused on the improvement of sustainable fishing as a livelihood and on a variety of supplementary livelihoods. The most usual institutional intervention being implemented was the setting up of local community people's organizations. Major factors which may influence success or failure of coastal management and recommendations on research, community organizing and livelihood, legislation and policies, implementation and coordination, and networking are also summarized. 相似文献
159.
Earl J. Baker 《Coastal management》2013,41(4):263-283
Abstract Risk from the “natural event system”; of hurricanes varies greatly along the U.S. coastline, and so do the property and lives at risk. Damage potential from storm surge in the Miami area is less than a third that of the Tampa area. However, damage potential from winds in the Boston and New York areas exceeds that of either the Miami or Tampa areas. Passage of time since the great hurricane disasters near the turn of the century and improvements in the warning system may make coastal dwellers underestimate the likelihood of a hurricane catastrophe. But population growth near the coast has been more than three times the national average, and 10 of 58 coastal segments 50 miles in width more than doubled in population between 1960 and 1970. Twenty‐two segments increased by more than 25,000 people with six increasing by 150,000. Legislative response to the growing hazard has varied as widely as risk but is not clearly correlated with risk. 相似文献
160.
An adjoint 1-D model was used to determine vertical diffusivity coefficients from temperature profiles collected within a filament escaping from the Galician coast following an upwelling event. The optimisation scheme ended with relatively high diffusivity values within the thermocline (9×10−5 m2 s−1). Such high values are relevant for biogeochemical exchanges between surface and deep waters in stratified areas.The optimised values were several orders of magnitude higher than the bulk of diffusivity measurements recorded with a free-falling device; however, the optimisation solution was consistent with the arithmetic mean of the measurements in the thermocline (7.7×10−5 m2 s−1), giving more weight to the few largest values. Below the thermocline, the data assimilation method failed because of the three-dimensional nature of the advective field of the upwelling system. Ignoring this advective forcing in the model led to estimates that were two orders of magnitude too high.The results suggest that turbulent mixing is a random process where a few intense events determine the average mixing that drives the long-term evolution of the water column structure. This statistical property is very important when one wants to use instantaneous diffusivity measurements for modelling purposes. 相似文献