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21.
A useful index of the status of women should be mappable, in order to allow global and regional comparisons. Ideally, such an index should include political, economic, and social components. In actuality, data that measure political and economic equality are available only in Western societies. An index that measures the general well-being of women, however, can be mapped and used crossculturally. An index is proposed that includes indicators from the areas of health, education and fertility.  相似文献   
22.
A physically-based semidistributed model, TOPMODEL, is applied to a 340 hectare spruce forested catchment in mid-Wales. the model is calibrated to runoff and the subsurface flow is divided into components of flow identified by depth of origin. in addition, chemical mixing techniques are used to provide a hydrograph separation between acidic soil waters and well buffered deep waters. the short-term variations in the components of flow identified by these two approaches compare well.  相似文献   
23.
This paper explores the partnership between a community group and a geography department to assess the wind energy potential of the Blueskin Bay region in southern New Zealand. The partnership has provided opportunities for research and is of strategic importance. Year‐long wind observations and numerical modelling have revealed that the hills surrounding Blueskin Bay show potential for wind energy generation. Despite challenges for both parties, the university–community partnership has allowed a successful research platform to be established.  相似文献   
24.
Well before President Putin ratified the Kyoto Protocol, the debate had begun as to the appropriate form of any post-Kyoto agreement. Amongst the emission reduction regimes being considered is that of Contraction and Convergence; conceived by Global Commons Institute (GCI) as a practical interpretation of the philosophy that “every adult on the planet has an equal right to emit greenhouse gases”. To support the Contraction and Convergence regime, the GCI have developed a computer model, CCOptions, to correlate CO2 stabilisation levels with global, regional and national carbon reduction targets. This paper analyses the model, concluding that, whilst the aim of CCOptions is laudable, the application of the model in its current form is unnecessarily ambitious and as a consequence potentially misleading to all but the well-informed user.  相似文献   
25.
Giant planets embedded in circumstellar discs are expected to open gaps in these discs. We examine the vertical structure of the gap edges. We find that the planet excites spiral arms with significant (Mach number of a half) vertical motion of the gas, and discuss the implications of these motions. In particular, the spiral arms will make the edge appear 'puffed up' relative to the bulk of the disc. Infrared observations (sensitive to dust) would be dominated by the light from the thick inner edge of the disc. Submillimetre observations (sensitive to gas velocities) would appear to be hot in 'turbulent' motions (actually the ordered motion caused by the passage of the spiral arms), but cold in chemistry. Resolved submillimetre maps of circumstellar discs might even be able to detect the spiral arms directly.  相似文献   
26.
We look at the large-scale dynamo properties of spatially periodic, time dependent, helical 2D flows of the form u(x, t)?=?(? y ?ψ?(x, y, t), ?? x ?ψ?(x, y, t), ?ψ (x, y, t). These flows act as kinematic fast dynamos and are able to generate a mean magnetic field uniform and constant in the xy-plane but whose direction varies periodically along z with wavenumber k. Using Mean Field Electrodynamics, the generation mechanism can be understood in terms of a k-dependent α-effect, which depends on the magnetic Reynolds number, R m . We calculate this effect for different motions and investigate how its limit as k?→?0 depends on R m and on the properties of the flows such as their spatial structure or correlation time. This work generalises earlier studies based on 2D steady flows to motions with time dependence.  相似文献   
27.
While current rates of sea level rise and associated coastal flooding in the New York City region appear to be manageable by stakeholders responsible for communications, energy, transportation, and water infrastructure, projections for sea level rise and associated flooding in the future, especially those associated with rapid icemelt of the Greenland and West Antarctic Icesheets, may be outside the range of current capacity because extreme events might cause flooding beyond today??s planning and preparedness regimes. This paper describes the comprehensive process, approach, and tools for adaptation developed by the New York City Panel on Climate Change (NPCC) in conjunction with the region??s stakeholders who manage its critical infrastructure, much of which lies near the coast. It presents the adaptation framework and the sea-level rise and storm projections related to coastal risks developed through the stakeholder process. Climate change adaptation planning in New York City is characterized by a multi-jurisdictional stakeholder?Cscientist process, state-of-the-art scientific projections and mapping, and development of adaptation strategies based on a risk-management approach.  相似文献   
28.
The effect exerted by the seabed morphology on the flow is commonly expressed by the hydraulic roughness, a fundamental parameter in the understanding and simulation of hydro- and sediment dynamics in coastal areas. This study quantifies the hydraulic roughness of large compound bedforms throughout a tidal cycle and investigates its relationship to averaged bedform dimensions. Consecutive measurements with an acoustic Doppler current profiler and a multibeam echosounder were carried out in the Jade tidal channel (North Sea, Germany) along large compound bedforms comprising ebb-oriented primary bedforms with superimposed smaller secondary bedforms. Spatially averaged velocity profiles produced log-linear relationships which were used to calculate roughness lengths. During the flood phase, the velocity profiles were best described by a single log-linear fit related to the roughness created by the secondary bedforms. During the ebb phase, the velocity profiles were segmented, showing the existence of at least two boundary layers: a lower one scaling with the superimposed secondary bedforms and an upper one scaling with the ebb-oriented primary bedforms. The drag induced by the primary bedform during the ebb phase is suggested to be related to flow expansion, separation, and recirculation on the downstream side of the bedform. Three existing formulas were tested to predict roughness lengths from the local bedform dimensions. All three predicted the right order of magnitude for the average roughness length but failed to predict its variation over the tidal cycle.  相似文献   
29.
As karst systems are natural windows to the underground, speleology, combined with geological surveys, can be useful tools for helping understand the geological evolution of karst areas. In order to enhance the reconstruction of the structural setting in a gypsum karst area (Vena del Gesso, Romagna Apennines), a detailed analysis has been carried out on hypogeal data. Structural features (faults, fractures, tectonic foliations, bedding) have been mapped in the ”Grotta del Re Tiberio” cave, in the nearby gypsum quarry tunnels and open pit benches. Five fracture systems and six fault systems have been identified. The fault systems have been further analyzed through stereographic projections and geometric-kinematic evaluations in order to reconstruct the relative chronology of these structures. This analysis led to the detection of two deformation phases. The results permitted linking of the hypogeal data with the surface data both at a local and regional scale. At the local scale, fracture data collected in the underground have been compared with previous authors’ surface data coming from the quarry area. The two data sets show a very good correspondence, as every underground fracture system matches with one of the surface fracture system. Moreover, in the cave, a larger number of fractures belonging to each system could be mapped. At the regional scale, the two deformation phases detected can be integrated in the structural setting of the study area, thereby enhancing the tectonic interpretation of the area (e.g., structures belonging to a new deformation phase, not reported before, have been identified underground). The structural detailed hypogeal survey has, thus, provided very useful data, both by integrating the existing information and revealing new data not detected at the surface. In particular, some small structures (e.g., displacement markers and short fractures) are better preserved in the hypogeal environment than on the surface where the outcropping gypsum is more exposed to dissolution and recrystallization. The hypogeal geological survey, therefore, can be considered a powerful tool for integrating the surface and log data in order to enhance the reconstruction of the deformational history and to get a three-dimensional model of the bedrock in karst areas.  相似文献   
30.
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