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41.
The key features of the western Galician shelf hydrography and dynamics are analyzed on a solid statistical and experimental basis. The results allowed us to gather together information dispersed in previous oceanographic works of the region. Empirical orthogonal functions analysis and a canonical correlation analysis were applied to a high-resolution dataset collected from 47 surveys done on a weekly frequency from May 2001 to May 2002. The main results of these analyses are summarized bellow. Salinity, temperature and the meridional component of the residual current are correlated with the relevant local forcings (the meridional coastal wind component and the continental run-off) and with a remote forcing (the meridional temperature gradient at latitude 37°N). About 80% of the salinity and temperature total variability over the shelf, and 37% of the residual meridional current total variability are explained by two EOFs for each variable. Up to 22% of the temperature total variability and 14% of the residual meridional current total variability is devoted to the set up of cross-shore gradients of the thermohaline properties caused by the wind-induced Ekman transport. Up to 11% and 10%, respectively, is related to the variability of the meridional temperature gradient at the Western Iberian Winter Front. About 30% of the temperature total variability can be explained by the development and erosion of the seasonal thermocline and by the seasonal variability of the thermohaline properties of the central waters. This thermocline presented unexpected low salinity values due to the trapping during spring and summer of the high continental inputs from the River Miño recorded in 2001. The low salinity plumes can be traced on the Galician shelf during almost all the annual cycle; they tend to be extended throughout the entire water column under downwelling conditions and concentrate in the surface layer when upwelling favourable winds blow. Our evidences point to the meridional temperature gradient acting as an important controlling factor of the central waters thermohaline properties and in the development and decay of the Iberian Poleward Current. 相似文献
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43.
Ruth Brennan 《Coastal management》2013,41(5):587-599
The North Norfolk coast is a naturally eroding coastline that has been subject to various management strategies over time, many of which have impeded its natural evolution. The Kelling to Lowestoft-Ness Shoreline Management Plan underpins management of the North Norfolk coast, advocating policies of managed realignment and no active intervention for much of this coastline. Implementation of these policies would give rise to significant loss of housing in North Norfolk during the course of this century. This has caused intense conflict between local communities and coastal planners, with the former feeling abandoned to the vagaries of natural coastal processes. Coastal planners need to work closely with local communities to implement a long-term vision for a sustainable coast. The issues of conflicting land-use planning policies and compensation for affected communities must be addressed. The wider implications of current management strategies are not fully understood and may, in some cases, be unsustainable. 相似文献
44.
沿海高速河北段工程地质、水文特性比较特殊,在路基高度、路基填料、路基断面等方面均有必要进行设计优化,可使设计方案更经济合理、技术可行、安全环保。 相似文献
45.
In many coastal states and territories, coastal zone management (CZM) programs have been the prime catalyst in leveraging public access initiatives among state and federal agencies, public organizations, and the private sector. A wide range of tools are used, including acquisition, regulations, technical assistance, and public education. The diversity of approaches is illustrated through a variety of case examples. Although hard numbers for measuring outcomes were not uniformly available, between 1985 and 1988, when federal and state CZM funding dedicated to public access was tracked, $141.5 million (unadjusted 1988 dollars) were spent on 455 public access-related projects. A policy shift occurred in the 1990s away from reliance on acquisition and regulation as the most effective means of providing access and toward technical assistance and public outreach-a response to the overall decrease in funds available for access. CZM programs have been able to balance the contradictory goals of the federal Coastal Zone Management Act of 1972 (CZMA), such as protecting coastal resources while providing for increased public access to those resources. It is recommended that CZM programs conduct assessments to determine the kind of access needed in the future and where it should be located. And, due to the creativity and innovation that states and territory coastal programs use to achieve access, it is recommended that a national clearinghouse be established for documenting and sharing information on innovative tools and programs. 相似文献
46.
Participation by local governmental officials is not given the same attention in the literature as that of citizens, publics, technical experts, or stakeholders. Yet, local governments are often a keystone to successfully implementing and enforcing coastal management policies. Qualitative analysis of open-ended interviews with local government officials from three national estuary program applications in New England revealed factors related to nine themes that shaped decisions to participate or not. Three categories of factors help to clarify the different types of influence agencies have over local government officials' decisions about whether or not to participate: factors associated with the character of individuals, with the context, and with the process. This taxonomy helps to clarify the kinds of opportunities available to project leadership to influence local government officials toward participating in regional coastal management processes. An important finding is that project staff should listen and learn about the concerns of local government officials and then create a process that accommodates and overcomes barriers to their participation. 相似文献
47.
Susie Westmacott 《Coastal management》2013,41(1):67-84
Integrated coastal management has been seen as the way to deal with the challenges currently facing managers of our coastal zones. In the tropics, these areas are typified with resources such as coral reefs and mangroves that are able to support a variety of activities. Integrated coastal management takes a multi-disciplinary approach that involves the integration of the different institutions and stakeholder groups in the coastal zone. A survey of tropical coastal locations revealed that fully implemented integrated coastal management is limited with programs apparently failing at the implementation stage. These coastal zones share a number of common challenges exacerbated by poverty and conflicts between the coastal activities. Conflict management needs to be incorporated into the management process that pays particular attention to the overextraction of resources and destructive resource use. 相似文献
48.
Chile has been attempting to establish a Management Area (MA) system that melds the use of marine protected areas with marine tenure. The process has brought to the fore the competing interests of various user groups: artisanal fishermen, marine science professionals, government managers, tourist developers, and the Navy. We explore the core relationships among fishermen and the ecologists and biologists whose work is essential for establishing and maintaining a MA. The MA system's creation and implementation raise the key question of whether a marine tenure system can work under the conditions imposed by the Chilean government. There is a need to recognize and reconcile contradictions in a government management model that strives simultaneously to be a conservation zone and a financially profitable co-management zone. This article examines the MA management system's fault lines in the context of Chile's political economy, and the intimate interaction of management with fishermen's cultural survival strategies. 相似文献
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Michael MacLeodr Andrew Cooperrn John McKenna James Power Anne-Marie O'Hagan 《Coastal management》2013,41(4):303-322
This article examines the use of inland mined sand and offshore dredged sand for beach nourishment projects in North Carolina, focusing on the question of whether inland mined sand is economically preferential for hot‐spot erosion control. Excavation, processing, and transport costs are presented, and cost efficiencies of hypothetical beach nourishment projects are compared. Cost analyses indicate that inland mined sand is economical for small projects (10,000–50,000 cubic yards), given that a clean sand source can be located within 15 miles of the nourishment site. The two factors primarily influencing per cubic yard costs of inland sand are overland transportation expenses and processing costs. The use of dredged offshore sand is less expensive for large projects (> 100,000 cubic yards) due to the economies of scale affecting dredge mobilization. Large beach nourishment projects in North Carolina will most likely continue to utilize offshore dredged sand. 相似文献
50.