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21.
Shaw Badenhorst Karen L. van Niekerk Christopher S. Henshilwood 《African Archaeological Review》2014,31(1):25-43
The ~100 ka Middle Stone Age levels at Blombos Cave, southern Cape, South Africa, contain numerous rock hyrax (Procavia capensis) remains. It is often ambiguous to interpret rock hyrax remains from archaeological deposits deriving from cave and shelter sites in southern Africa as the agent or agents of accumulation may be difficult to establish. In this paper, the different taphonomic signatures separating anthropogenic from natural accumulations at Blombos Cave are considered. The analysis indicates that although a few specimens show evidence for raptor and carnivore accumulation, there is also substantial evidence that suggests humans preyed on these small mammals during different times of the year. 相似文献
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Abstract This study examines the effects of the risk from transporting high–level radioactive waste to the proposed Yucca Mountain repository on housing location decisions in Southern Nevada. Using data from a survey of southern Nevada households, we develop a model–based subjective risk estimate for each household. We then explore different factors that may influence the household's location decisions if the proposed transportation route is ultimately chosen for nuclear waste transport. We extend the conventional expected utility model to allow for uncertainty surrounding the actual risks borne by the household. Finally, we examine the impact of federal government compensation on households' location decisions. The findings indicate that residents currently living near the proposed transportation route express subjective risk estimates much larger than those reported by the Department of Energy. In general, households that are uncertain about the future risks are more likely to relocate than those expressing certainty. When everything is considered, the model predicts that between one and three percent of households living near the transportation route are likely to relocate. Compensation can influence some households to remain at their present location and bear the transport risk. 相似文献
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Jon Seal 《International Journal of Nautical Archaeology》2003,32(2):238-245
This is the story of the building of a replica Viking craft. Being only 22 ft (6.7 m) long and having 4 ft 6 in (1.37 m) beam, the Gokstad faering does not conform to our usual image of a Viking boat. However, the smaller craft shows all the construction details found in the larger ships. A close examination can help us to see some of the principles the Vikings applied to their boatbuilding. 相似文献
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In recent years, Head Start's prominent role in preparing low‐income 4‐year‐olds for school has been affected by rapid growth in state‐funded pre‐K programs, some of which are based in public schools. This has led to questions about the comparative advantages of these two approaches to early education. An analysis of data from Tulsa, Oklahoma, indicates that the school‐based pre‐K program is more effective in improving early literacy outcomes, while Head Start is more effective in improving health outcomes. The two programs are comparable with regard to early math learning. Social–emotional effects are more subtle, but the school‐based pre‐K program has demonstrable positive effects, while the Head Start program does not. 相似文献
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Although the dietary importance of barnacles is recognized in Europe and elsewhere around the world, indigenous use of barnacles on the Pacific coast of North America has not been well-documented. On the Northwest Coast, most shell middens located along estuaries are dominated by clams (such as Saxidomus, Protothaca, etc.), while those on the outer coast are dominated by mussels (Mytilus californianus). At Kit’n’Kaboodle Cave in southeast Alaska, the acorn barnacle Semibalanus cariosus is unusually abundant over a 3500-year period, but is replaced by mussels over time. These results are placed within a larger geographic context to more closely examine patterns of barnacle use by First Nations of the Pacific Northwest. 相似文献
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