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991.
A theory of ethnogenesis is advanced, associating stability of ethnic communities with homogeneous landscapes and ethnic change leading to the formation of new communities with heterogeneous landscapes. The ethnic aspect of population, unlike the social and political aspects, is found to be a function of geographical factors. The study of the interplay between ethnic man and the environment does not require an integration of the geographic disciplines but can be investigated within the framework of a special discipline, say, ethnology within geography.  相似文献   
992.
993.
Reductions of the cost increments of northern development depend to a large extent on the manufacture of machines and equipment with northern specifications designed for operation under low temperatures. Existing definitions of the northern regions of the USSR are not suitable for this purpose. An engineering-geographic regionalization of the USSR is therefore proposed, defining the area of application of specially designed northern machines on the basis of a harshness scale that relates climatic harshness to its effect on machines. The key threshold values on this harshness scale are 4.6, above which ordinary structural steel loses strength and is subject to harshness-related ruptures; 5.3, above which ordinary structural steel becomes brittle and is affected by a fifty-fold increase of ruptures; and 7.9, above which ordinary steel can no longer perform.  相似文献   
994.
995.
Geographical structures consisting of a sequence of ratios are examined from the point of view of homogeneity. Several measures of homogeneity are introduced. It is shown that any two such structures are not necessarily comparable in terms of homogeneity and their measures of homogeneity do not necessarily agree. One way of achieving agreement among homogeneity measures is to link the homogeneity of structures to the operation of smoothing, based on one of the properties stated by C. E. Shannon for entropy in information theory.  相似文献   
996.
A Soviet visiting geographer assesses the state of geography at Canadian universities in the light of Soviet experience. The system of higher education in geography is found to have expanded considerably in recent years, partly through the formation of new universities and the creation of new geography departments. Despite relatively weak links among universities and a wide diversity in research topics, each major department appears to have specialized in certain areas. This is partly a result of efforts by the Canadian Association of Geographers. The status of various geographic disciplines is briefly reviewed.  相似文献   
997.
A method of “structural chains” is proposed for the analysis of regional urban systems. Each chain is made up of a sequence of numerical elements representing the average population of places at various levels of urban development, from small mining or forestry settlements to large polyfunctional cities of regional or national rank. The absence of a particular category in a region is marked in the chain by a zero. The structural chains of local urban systems can be grouped into tables reflecting the structure of a regional urban system and its local variations. The key characteristics of urban systems reflected by these chains are: the number of elements or levels of development; the number of zeros and their position in the chain, reflecting the degree of development of the urban hierarchy; and the height of the regional tables (number of horizontal rows), representing the number of local urban structures. The method is tested and illustrated by the urban systems of the Dnieper-Donets and Black Sea regions of the Ukraine, the Upper Volga region, and the urban system of the Tatar ASSR.  相似文献   
998.
A regionalization of Moscow Oblast is derived from a physiologic-climatic evaluation for purposes of settlement and recreation. The evaluation is based on the frequency of occurrence of particular classes of weather through the year. The most common classes in Moscow Oblast are the 1C class (light negative heat balance), which is determined by global macrofactors and produces an undifferentiated background in the oblast, and the N class (comfortable condition of heat equilibrium) and 2C class (moderately negative heat balance), which reflect more localized factors and can be used for a differentiated evaluation of physiologic-climatic conditions. Eleven physiologic-climatic regions are delimited on the basis of the difference between the number of days with comfortable conditions (N class) and the number of moderately cold days (2C class). Optimal conditions for settlement and recreation are found south and southeast of Moscow; the most unfavorable in the low-lying swampy Dubna area, where the Moscow-Volga canal meets the Volga River.  相似文献   
999.
Spaee-time shifts are analyzed for a particular type of suburban recreational, development—the cottage, settlements and garden cooperatives around Moscow. Measurement of the appearance, stabilization and decline of this recreational function along six major rail lines radiating from Moscow shows a centrifugal shift fostefed by the development of high-speed transportation and the conversion of older recreational areas close to the city to residential and industrial uses. A characteristic feature of the expansion of the recreational zone Over time has been a leaping movement in which the centers of recreational development, after having taken shape for one or two decades, will suddenly leap outward to a more distant zone. Furthermore, suburban cities are beginning to generate their own demand for recreational space and are becoming nuclei of their own recreational zones.  相似文献   
1000.
The study of oceans as a subfield of geography has gained acceptance in the Soviet Union. Some universities have introduced courses in marine geography, and geographers have participated in oceanographic research voyages. An effort is made here to define the place of a marine geography within the geographic discipline as a whole, to set the spatial limits for geographical investigations of the oceans and to suggest problem areas suitable for geographical analysis. In keeping with the Soviet dichotomy, physical and economic geographic problems are distinguished. Physical-geographic problem areas would include study of oceanic water masses; large-scale interaction between oceans and atmosphere; study of island environments, and the biogeography of oceans. Economic geographic problems would focus both on theoretical aspects, such as spatial regularities in human activities related to oceans, and on applied aspects, providing a sound basis for economic development of ocean areas.  相似文献   
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