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101.
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THE PALEOLITHIC CAVE ART OF VASCO-CANTABRIAN SPAIN 总被引:1,自引:0,他引:1
LAWRENCE G. STRAUS 《Oxford Journal of Archaeology》1987,6(2):149-163
Summary. This article explores the relationship between cave art and Upper Paleolithic archeology in northern Spain (and extreme southwestern France). Among the 83 known art sanctuaries, only three can probably be terminus ante quem dated to the early Upper Paleolithic (c. 35,000-20,000 BP). Other types of evidence (virtual absence of ornaments and mobile art objects before the Solutrean, stylistic similarities between works of late Upper Paleolithic mobile art and parietal art, overwhelming association of Solutrean and/or Magdalenian cultural deposits with art sanctuaries) clearly suggest that most of the cave art was done in the period between c. 20,000-10,000 BP. Cave art sanctuaries are distributed in non-random fashion. The clusters of sanctuaries usually correspond with dense clusters of habitation sites. The clusters are separated by substantial geographical gaps. These chronological and geographical facts coincide with contemporaneous subsistence intensification, all of which tends to support the hypothesis of increased territorialism in the late Last Glacial. 相似文献
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The upper Mersey Valley was glaciated on three occasions during the Pleistocene. The youngest, Rowallan Claciation, probably commenced after 28000 years B.P. The maximum ice limit was attained before 13500 years B.P., and retreat occurred before 10000years B.P. Deposits associated with Rowallan Glaciation are weakly weathered chemically. They overlie moderately weathered deposits that were formed during the Arm Glaciation, which is inferred from relative dating data to have occurred before the Last Interglacial Stage. North of the deposits and ice limits of the Arm Glaciation extremely weathered tills and rhythmites occur. They were formed by ice of the Croesus Glaciation which is inferred to be of Early Pleistocene age or older. 相似文献
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David M. Mark 《Geographical analysis》1987,19(3):264-272
A new and recursive algorithm for determining proximal polygons is based on quadtree concepts. The algorithm can use any distance metric, and produces a quadtree of the image of the proximal polygons. This can be converted to vector form, or be incorporated directly into a quadtree-based geographic information system, in order to solve a number of closest-point problems. The algorithm can also produce the Delaunay triangulation, which is the dual of the proximal polygons. Empirically, the running time of the algorithm is proportional to the number of centers raised to the 1.6 power. 相似文献
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Fyle CM 《Africa : journal of the International Institute of African Languages and Cultures》1987,57(4):498-509
243 blacksmiths in Sierra Leone were interviewed in 1984-85 in an effort to focus on both the activities and attitudes of traditional blacksmiths in the country's economy. Due to the fact of an shortage of foreign exchange with which to import and maintain equipment, agriculture using high-technology equipment accounts for less than 15% of total production. Consequently, blacksmiths are vital to the nations' survival, despite prevailing attitudes toward them. The interviews were conducted in 9 of the 12 districts in Sierra Leone. The blacksmith operates not simply in terms of producing and servicing goods; cultural values frame his position in the community. In all of West Africa, and particularly among Mende-related peoples, there historically exists a mystique surrounding a blacksmith. In some societies, blacksmiths were believed to be witches. The arguments that most likely could account for this would probably lie in the fact that the blacksmith made farm tools and weapons of war, means of survival in the community. Thus, his position was vital. Traditionally the importance of the smith's profession lies in the fact that some of the implements he fabricates and the materials he uses are believed to provide elements of social control or to have healing powers. An appreciation of the cultural significance of the blacksmith demonstrates the degree of attachment of the population to this profession as well as the context within which one could relate to possible technological changes in the trade. An attempt was made in the interview to gather some information about levels of production. The figures represent averages, and production capacity varied owing to a number of factors, including the degree of organization of the unit, the capacity of the head of the forge to keep his team busy when work was intensive, and the degree of energy and determination of an operator to get the greatest amount of work done in 1 day. The most obvious factor influencing production levels was the size of the units. Pricing of commodities and the blacksmith's services depended on a combination of factors, but, generally, in semi-urban areas, where more impersonal relationships tended to obtain, prices appeared relatively more fixed than in rural areas. All smiths interviewed complained about the increasing scarcity of scrap iron. As there is every reason to envisage a continued dependence on informal-sector production by blacksmiths, official attitudes need to take these trades more seriously. 相似文献
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