全文获取类型
收费全文 | 7984篇 |
免费 | 101篇 |
专业分类
公路运输 | 1729篇 |
综合类 | 591篇 |
水路运输 | 2561篇 |
铁路运输 | 774篇 |
综合运输 | 2430篇 |
出版年
2022年 | 113篇 |
2021年 | 58篇 |
2020年 | 47篇 |
2019年 | 82篇 |
2018年 | 197篇 |
2017年 | 117篇 |
2016年 | 150篇 |
2015年 | 92篇 |
2014年 | 242篇 |
2013年 | 1222篇 |
2012年 | 324篇 |
2011年 | 396篇 |
2010年 | 247篇 |
2009年 | 368篇 |
2008年 | 316篇 |
2007年 | 274篇 |
2006年 | 231篇 |
2005年 | 271篇 |
2004年 | 293篇 |
2003年 | 185篇 |
2002年 | 150篇 |
2001年 | 135篇 |
2000年 | 139篇 |
1999年 | 106篇 |
1998年 | 129篇 |
1997年 | 111篇 |
1996年 | 138篇 |
1995年 | 149篇 |
1994年 | 84篇 |
1993年 | 189篇 |
1992年 | 160篇 |
1991年 | 77篇 |
1990年 | 83篇 |
1989年 | 57篇 |
1988年 | 74篇 |
1987年 | 65篇 |
1986年 | 59篇 |
1985年 | 77篇 |
1984年 | 73篇 |
1983年 | 73篇 |
1982年 | 73篇 |
1981年 | 95篇 |
1980年 | 68篇 |
1979年 | 91篇 |
1978年 | 56篇 |
1977年 | 69篇 |
1976年 | 53篇 |
1975年 | 65篇 |
1974年 | 50篇 |
1973年 | 45篇 |
排序方式: 共有8085条查询结果,搜索用时 78 毫秒
361.
Sarah L. Richardson 《Coastal management》2013,41(1-2):21-46
Abstract Urban waterfronts are increasingly the focus of revitalization efforts designed to enhance tourism and recreation. The evolution of urban waterfronts suggests that these resources experience distinct stages of introduction, growth, maturity, decline, and sometimes revitalization. In this paper the product life cycle is broadened to describe the evolution of the waterfront district of Galveston, Texas. Implications of the product life cycle model of urban waterfront revitalization pertain to public policy formation, “product”; development, and management response to different life cycle stages. 相似文献
362.
William H.K. Lam 《运输规划与技术》2013,36(4):245-258
This paper investigates the role of transport pricing in network design and describes two facts about flow pattern in a transportation system. The first, illustrated by an example of Braess paradox, is that adding a new link to the network does not necessarily minimize the total travel time. The second is that introducing of appropriate toll pricing may reduce not only the total network time but also the travel time for each individual traveller. It follows with the investigations of different system objectives and different pricing policies (only toll pricing and distance‐based pricing are considered), and shows how they affect the system performance and flow pattern. Lastly, a systematic optimization process is proposed for integrated planning of transport network and pricing policies. 相似文献
363.
C. O. Ikporukpo 《运输规划与技术》2013,36(3-4):181-188
In spite of the fact that about 70% of Nigeria's population live in rural areas, these areas have remained largely inaccessible. Not only do they lack motorable roads and organized public transport but also field surveys indicate that nearly all rural inhabitants do not have a private car. A Directorate of Food, Roads and Rural Infrastructure has been set up to manage the inaccessibility problem, among others. Whereas there are several conventional approaches to the management of the rural transportation problem, the Nigerian approach relies on the provision of roads. This restrictive approach with an emphasis on locational to the neglect of personal accessibility has various limitations which are analysed. 相似文献
364.
L. R. Roueche 《Maritime Policy and Management》2013,40(1):19-29
In this paper, in which the author attempts to redress the lack of attention by economists to ferry operation, a simple pricing model, based on marginal cost pricing, is developed. 相似文献
365.
Tae-Woo Lee Nam-Kyu Park John F. Joint Woong Gyu Kim 《Maritime Policy and Management》2013,40(2):133-144
There have been many efforts to develop a logistics information system in the Korean logistics industry. In spite of these efforts, there are many points which need improvement in the Logistics Information System, of which function is the electronic data communication without added value. This paper aims to describe some of the main problems and the successful factors which are being found in the evolution of the present EDI systems for clearing import/export container cargoes, with special reference to Singapore, Korea, and Japan. Following this, leaving legal issues aside, to suggest workable guidelines for designing a new efficient EDI system for container cargo logistics. As a result of the review, the following successful factors are drawn: (a) the planning, requirement analysis and design of EDI are critical, as it provides a framework for its implementation; (b) as the data of customs clearance are an integral part of a logistics EDI system, the inclusion of customs in the system design is essential; (c) the sharing system of cargo data as the framework of the logistics EDI is efficient for data interchange; (d) the EDI software for the user has been developed and provided by an EDI network operating company; and (e) to facilitate communication between trading partners and the transport sector, it is necessary to adopt a global message standard, such as EDIFACT. 相似文献
366.
Green turtles (Chelonia mydas) are among the most high profile species in San Diego Bay, California, and understanding impacts of coastal development and industry is essential to the management and conservation of this local population. Here we describe power plant changing energy production and its impact on turtle habitat use and our ability to research and manage this population. For over 20 years, green sea turtles have been captured, assessed, and tagged near the South Bay Power Plant (SBPP) in the San Diego Bay; from 2002–2011, 104 turtles were captured on 212 occasions. As the 50-year-old SBPP generates less energy, effluent patterns change and water temperatures decrease, presumably to more natural conditions. There has been a concurrent decrease in turtle-capture success, perhaps due to lesser visitation to the effluent site where nets are tended. Seasonal catch-per-unit-effort declined from a high of 4.14 turtles per monitoring day, to a nine-year low of 1.33 during the 2010–2011 season. It is already apparent that management decisions related to energy policy are affecting the habitat and behavior of this stock of endangered turtles. Green turtles are expected to remain in the San Diego Bay after the SBPP becomes inoperative and continuing research will monitor future impacts and distribution shifts resulting from the expected changes in thermal pattern within south San Diego Bay. Research efforts to study this population (i.e., capture methods and locations) will require modification in response to these changes. Lessons learned here are applicable to the immediate coastal development of San Diego, as well as at similar interactions between marine turtles and industrial thermal effluent discharge throughout Southern California, the United States, and beyond. 相似文献
367.
Coastal Resources Management: Beyond Market and Bureaucracy by Robert B. Ditton, John L. Seymour, and Gerald C. Swanson. Published by D. C. Heath and Company, Lexington, Massachusetts, 1977, 191 pp., 6 figures. The Urban Sea: Long Island Sound by Lee E. Koppelman, Peter K. Weyl, M. Grant Gross, and DeWitt S. Davies. Published by Praeger Publishers, 1976. 209 pp., 81 figures, 42 tables. 相似文献
368.
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
369.
370.
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