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681.
Nearly 200 rock art sites of Upper Paleolithic age are currently known on the Iberian Peninsula, in both caves and the open air. Over half are still concentrated in Cantabrian Spain and they span the period between c. 30–11 kya, but–tracking the course of human demography in this geographically circumscribed region–many of the images were probably painted or engraved during the Solutrean and, especially, Magdalenian. Dramatic discoveries and dating projects have significantly expanded the Iberian rock art record both geographically and temporally in recent years, in close coincidence with the growth of contemporaneous archeological evidence: cave art loci in Aragón and Levante attributable to the Solutrean and Magdalenian, many cave art sites and a few open-air ones in Andalucía and Extremadura that are mostly Solutrean (in line with evidence of a major Last Glacial Maximum human refugium in southern Spain), the spectacular Côa Valley open-air complex in northern Portugal (together with a growing number of other such loci and one cave) that was probably created during the Gravettian-Magdalenian periods, and a modest, but important increase in proven cave and open-air sites in the high, north-central interior of Spain that are probably Solutrean and/or Magdalenian. Despite regional variations in decorated surfaces, themes, techniques and styles, there are broad (and sometimes very specific) pan-Iberian similarities (as well as ones with the Upper Paleolithic art of southern France) that are indicative of widespread human contacts and shared systems of symbols and beliefs during the late Last Glacial. As this Ice Age world and the forms of social relationships and ideologies that helped human groups survive in it came to an end, so too did the decoration of caves, rockshelters and outcrops, although in some regions other styles of rock art would return under very different conditions of human existence.  相似文献   
682.
683.
This paper presents the integration of automated sensors based on a terrestrial laser scanner and an amateur digital camera with the aim of generating a photorealistic three-dimensional (3D) model of the Principal Panel in Pindal Cave (Spain). The approach developed for 3D modelling overcomes many of the problems related to the independent implementation of photogrammetry and laser scanning. Particularly, a sequential and hierarchical approach was developed based on the processing and matching of images from the camera (camera image) and the laser scanner (range image). The results obtained demonstrate that the workflow for this model is automatic, effective, and accurate. The presented approach was found to create hyper-realistic models, even improving upon human visual capabilities.  相似文献   
684.
In the Wahiba Sands of eastern Oman, luminescence dating of sands enables us to relate wind activity to climatic variations and the monsoon cycle. These changes resulted from Polar glacial/interglacial cyclicity and changes in global sea levels and wind strengths. Luminescence dates show that development of the Sands began over 230 ka ago when the sand-driving winds were the locally arid, northward-blowing SW Monsoon.  相似文献   
685.
This study is focused on the El Milagro mine (Asturias, Spain) and is part of a large‐scale effort on the measurement of the lead isotopic composition of Spanish copper ores from prehistoric mines in the provinces of Asturias and León, from which no data were available until recently. Lead isotopic values are compared to the published lead data from the El Aramo mine in the same region. The results show that both mines have a very similar lead isotopic composition, apart from some highly radiogenic samples in the El Milagro mine, which are clearly different from those previously reported for the Iberian Peninsula.  相似文献   
686.
Handaxes, simple flakes and retouched flakes are three types of stone tools whose adaptive advantages are highly debated. Interpretations of these technologically different tools suggest that their adequacy for butchery is uneven. Although some experimentation has been made in this regard, further research is needed to understand which of these tool types are more efficient for butchery, thus granting adaptive advantages to the hominins who used them. The present experimental work shows that small handaxes provide higher return rates in butchery activities than simple and retouched flakes. Efficiency (measured in time) is significantly positive in handaxes compared to the other tools when defleshing. In contrast, when comparing the three stone tool sets (simple flakes, retouched flakes and handaxes), the return values obtained for disarticulation are very similar. This study also shows that cut marks do not occur randomly and are less stochastic than previously assumed. Defleshing leaves a preferential cluster of cut marks on mid‐shafts from long bones and even on these sections, depending on element type, patterns are statistically demonstrable.  相似文献   
687.
688.
Outright victories against urban elitisation are rare in the current urban revolution. This article highlights how urban elitisation is confronted in Chacao, the most elite and urban part of Venezuela. Initially it reviews how this urban elitisation created the main economic, political and military strongholds of the opposition to the Bolivarian revolution. Then, in contesting it, the urban and Bolivarian revolutions feed each other through women's participation in invited and invented spaces of citizenship. From such spaces, Chacao women in their settler's movement organised struggles of insurgent citizenship to stop elitist urban renewal agendas and develop further forms of insurgent urbanism to conduct an urban renewal from below and establish a New Socialist Community for 600 families. They emerged as a revolutionary class to implement Bolivarian policies addressing the inefficiency and opportunism of the bureaucratic state and contesting urban elitisation with an anti‐capitalist and anti‐imperialist insurgent urbanism.  相似文献   
689.
The conceptualisation of intersectionality has been one of the most important contributions to feminism, as it allows for theorisation about multiple and intersecting oppressions. This contributes to a more complex and dynamic understanding of social relations and power structures, and it acknowledges the differences between categories, but it has no methodological direction. I try to take this debate a step forward, by developing what I have called Relief Maps: a new way of collecting, analysing and displaying intersectional data. I consider Relief Maps to be a sound tool for studying the Geographies of Intersectionality, as they show the relationship between three dimensions: power structures (the social), lived experience (the psychological) and places (the geographical). By showing some examples of them, I demonstrate how Relief Maps make empirical work on intersectionality possible and how they are able to take into account both privilege and oppression without using categories in a fixed and rigid way. Taking the spatial dimension as a central part of the analysis, they show how the relationship between power structures varies depending on places and also illustrate how subject formations are done and undone through everyday spaces. Relief Maps aim to take the potentialities of intersectionality and minimise its limitations: they intend to disrupt homogeneous categories while pointing towards the material consequences of oppression. Finally, Relief Maps also provide some insights on intersectionality itself, as they help to think about how power structures relate to each other and the role that experience and place play in these processes.  相似文献   
690.
This paper analyses the effects of R&D expenditure in the higher education sector on the scientific production across regions in Europe 15. Our research questions relate to the regional production of science and the role of academic R&D expenditures on regional scientific output. The results show that money affects the production of scientific results in regions. On average, we found different impacts and lags of R&D expenditure according to the level of regional development. Our findings also suggest that scientific specialization is a significant factor affecting scientific outputs, although its effects differ across disciplines and regions.  相似文献   
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