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21.
A total of over 32,000 demersal fish and epibenthic crustaceans belonging to 62 species were caught in 42 biweekly trawls from 10 stations in Yaquina Bay, Oregon, during 1967 and 1968. English sole,Parophrys vetulus, was the most abundant species. Seventeen species (13 fishes and 4 crustaceans) constituted 95% of the catch. Total numerical abundances of both individuals (mainly juvenile fishes) and species were greatest in the lower 12 km of the estuary during summer and early fall, a period of water mass stability and increased water temperature and salinity. This section of the estuary is used by many immature fishes and crustaceans as a “nursery area”. These fishes generally emigrate from the estuary as subadults in the fall around the onset of the rainy season. The fewest species were taken in January 1968 from the central, upper-estuarine, and riverine areas of the bay, this being a time when high rainfall and river discharge result in low salinity and temperature. Crustaceans (shrimp and subadult crabs) were generally most abundant in late winter and early spring throughout the estuary. Changes in diversity indices reflected variations in community structure, the influence of migratory species and juvenile fishes, and seasonal changes in dominance. Year-to-year fluctuations in abundance may be due, in part, to local hydrographic and meteorological conditions along the central Oregon coast.  相似文献   
22.
DTM extraction from the ALS (Airborne Laser Scanning) point cloud is a complex task which involves many algorithms and numerical procedures. One of the first steps, performed to remove all of the terrain covering, is data filtration. There is a number of filtration methods and algorithms to chose from. In this paper we would like to propose a filtration method based on fuzzy logic. We present basic information regarding fuzzy logic, the design of fuzzy rules and an example of point cloud processing. For comparison, results from the ATIN filtration method are presented.  相似文献   
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The results of magnetovariational (MV) soundings are usually presented in the form of induction arrows. However, many examples show that the horizontal magnetic tensor (HMT) is more informative. The distribution of some HMT invariants directly traces the location of well-conducting rocks in the crust and upper mantle. The HMT determination requires simultaneous observations in an entire region, which is a substantial disadvantage. Yet, it is possible to apply techniques capable of restoring all the magnetic field components necessary for HMT estimation from tipper data arrays alone. These techniques exploit the spatial relationships between electromagnetic field components in a non-conducting atmosphere. For Central Europe, a large data set of induction arrows has been collected by the effort of many groups during the last 50 years. Based on these data, HMT values were calculated, and the results are very significant. The spatial behavior of certain HMT invariants demonstrates the presence of deeply seated, well-conducting rocks in the crust. Anomaly maximums display an arc-shaped trend that may be genetically linked with the Caledonian and/or Variscan margin thrust belts, which developed following the collision between Baltica and Avalonia and/or Gondwana-derived terranes, respectively. This is an important finding because the position of these deformation fronts in relation to the edge of the East European Platform is still controversial.  相似文献   
25.
Festivals are an increasingly common phenomenon. They strongly influence geographical space, and so are studied in depth by geographers. The author shows that festivals are a subject for research in different geographical sub-disciplines. The author also defines the research paradigm of the geography of festivals as a part of human geography. He also establishes the main aspects of festival research in geography: cultural, social, economic and time–space analysis, political, historical, general and theoretical. Finally, he suggests future directions in geographical research on festivals.  相似文献   
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ABSTRACT

The aim of the article is to present and discuss functions of public monuments in relation to different dimensions of geographical space. The authors discuss public spaces, monuments, public art, based on a mixed-method approach and an analysis of scientific literature as the main research method. The theoretical discussion is supplemented with the results of Internet searches and an analysis of media supplements, and specific examples are given, including some from Poland. An additional method was autoethnography, which involved an analysis of cultural phenomena based on the authors’ experience. The analysis revealed that monuments were part of public art and thus enriched public spaces in cities. They fulfilled different important functions: artistic, symbolic, commemorative, political, social, religious, marketing, and mixed. Additionally, the monuments reflected the contemporary transformation of ideas and social orders and therefore also reflected contemporary urban debates. They were products of social relations, powers, ideas, identities, and the collective memory reflected in the urban spatial structure of cities. The authors conclude that the examples presented in the demonstrate that monuments perform various functions in urban public spaces. From a spatial perspective, the role of monuments depends on their different impacts on people’s perceptions and interpretations of space.  相似文献   
27.
The marginal zone of the East European Platform, an area of key importance for our understanding of the geotectonic history of Europe, has been a challenge for geophysicists for many years. The basic research method is seismic survey, but many important data on physical properties and structure of the lithosphere may also be provided by the electromagnetic methods. In this paper, results of deep basement study by electromagnetic methods performed in Poland since the mid-1960s are presented. Over this time, several hundred long-period soundings have been executed providing an assessment of the electric conductivity distribution in the crust and upper mantle. Numerous 1D, 2D, and pseudo-3D electric conductivity models were constructed, and a new interpretation method based on Horizontal Magnetic Tensor analysis has been applied recently. The results show that the contact zone is of lithospheric discontinuity character and there are distinct differences in geoelectric structures between the Precambrian Platform, transitional zone (TESZ), and the Paleozoic Platform. The wide-spread conducting complexes in the crust with integral conductivity values reaching 10 000 S at 20–30 km depths are most spectacular. They are most likely consequences of geological processes related to Caledonian and Variscan orogenesis. The upper mantle conductivity is also variable, the thickness of high-resistive lithospheric plates ranging from 120–140 km under the Paleozoic Platform to 220–240 km under the East European Platform.  相似文献   
28.
Ohne ZusammenfassungAbgedruckt aus: Die Eruptivgesteine des Kristianiagebietes II. Die Eruptionsfolge der triadischen Eruptivgesteine bei Predazzo in Südtyrol. Videnskabsselskabets Skrifter I. Math.-naturv. Kl. Nr. 7, S. 1–3. Kristiania 1895.  相似文献   
29.
Surveys in Geophysics - This paper presents a three-dimensional (3-D) model of the resistivity distribution in the European lithosphere at the junction between the East European Craton, the...  相似文献   
30.

Background  

This study evaluates the carbon dioxide and other greenhouse gas fluxes to the atmosphere resulting from charcoal production in Zambia. It combines new biomass and flux data from a study, that was conducted in a miombo woodland within the Kataba Forest Reserve in the Western Province of Zambia, with data from other studies.  相似文献   
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