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61.
Abstract

The issue of whether power plants should be located on Wisconsin's Lake Michigan shore or inland is addressed in this article. It is quite likely that sites for several large power plants will be needed before the year 2000. Available evidence on the comparative costs of condenser cooling indicates that there may or may not be substantial economies from locating these plants at lakeshore sites depending on site characteristics, fuel costs, and other variables. Environmental impacts of coastal and inland siting are surveyed and also appear to be highly site‐specific. Important issues arise with respect to the intense competition for coastal land and the aquatic impacts at both coastal and inland sites. A third alternative, that of utilizing sites that are in the coastal zone but set back from the water's edge, has some promising aspects, but data on costs are scarce and inconclusive. Conclusions center on the importance of not ruling out either coastal or inland locations in future efforts to identify suitable power plant sites, the need to review current water‐quality measures, and the need for further research on institutions to facilitate sound siting decisions.  相似文献   
62.
Since the Rio conference in 1992 investments in integrated coastal management (ICM) have increased dramatically. National and subnational governments have undertaken many initiatives to protect and develop coastal areas. Extensive field experience has advanced understanding of the operational attributes of ICM. This article reviews the principles and operational attributes of ICM that have become well accepted, particularly from the perspective of international ICM donors and professionals. A common understanding of the fundamentals of ICM provides a base from which targeted and systematic study and assessment of ICM can be conducted. Several thematic areas are suggested where there are currently important needs and opportunities for collective study and learning in ICM. The important role of donors is emphasized in supporting collaborative learning initiatives that advance understanding of ICM, and improve and expand the practice.  相似文献   
63.
Abstract

An increasing threat to the marine environment is the presence of debris in the ocean, which is predominantly a result of land-based sources and increasing use of single-use packaging items. To begin reducing the amount of debris entering the ocean, human behavior must be addressed. The purpose of this study is to evaluate how coastal recreationists behave towards the environment and whether their participation in recreation correlates to their reported behavior specific to marine debris control. Path analysis was used to determine how one’s attitudes, knowledge, recreational activity, and background characteristics influence behavior. Results showed that type of recreational activity had very little impact on behavior and other predictors. From the model, marine environmental concern, connection to the marine environment, and gender most directly influenced reported behavior. Therefore, to encourage change in recreationists’ relevant behavior, the results indicate social groups where behavior change efforts could initially be made. Additionally, the marine environmental concerns of different demographic groups should be considered and used in developing programs directed at increasing environmentally responsible behavior with emphasis on marine debris.  相似文献   
64.
Note

This article is a short response to a critique by William Odum and Stephen Skjei of an earlier article by this author in this Journal entitled “Wetlands Preservation and Management on Chesapeake Bay: The Role of Science in Natural Resource Policy.”; It is a continuation of themes begun in that paper. It focuses on the question of determining the social value of wetlands preservation and the contradictory positions which ecologists fall into when discussing the value of wetlands.  相似文献   
65.
Abstract

Reliable predictive accident models (PAMs) are essential to design and maintain safe road networks, and yet the models most commonly used in the UK were derived using data collected 20 to 30 years ago. Given that the national personal injury accident total fell by some 30% in the last 25 years, while road traffic increased by over 60%, significant errors in scheme appraisal and evaluation based on the models currently in use seem inevitable. In this paper, the temporal transferability of PAMs for modern rural single carriageway A-roads is investigated, and their predictive performance is evaluated against a recent data set. Despite the age of these models, the PAMs for predicting the total accidents provide a remarkably good fit to recent data and these are more accurate than models where accidents are disaggregated by type. The performance of the models can be improved by calibrating them against recent data.  相似文献   
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This paper examines all the disparate technologies and techniques capable of smoothing the integration of public transport modes and services at both the urban and interurban scale. The paper focuses on the application of information technology and telematics solutions which have been designed to create as seamless a journey as possible from the point of view of the transport system user. The scope of the paper is therefore deliberately wide‐ranging and includes an examination of measures as apparently unconnected as smartcard ticketing, bus priority systems, automatic vehicle locationing, trip planning and on‐board information systems as well as new public transport services offering demand responsive travel and integration with taxi services. The paper intends to show how such technological solutions can be used to increase the attractiveness and competitiveness of fixed public transport networks in comparison to the door‐to‐door flexibility of the private car.  相似文献   
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