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31.
Cave bear (Ursus spelaeus) behavioural ecology, as evidenced through population dynamics, is crucial for improving our understanding of why this species went extinct. Despite the fact that the bones of this species have been recovered in very large quantities, allowing for extensive study, fundamental questions regarding its life-ways remain unanswered. We present research using geometric morphometrics (GMM) on molars to investigate population structure based on morphological variation over space and through time. This preliminary work deliberately restricts the geographic catchment area for sampling, allowing for a meaningful appraisal of scale of variation within a spatially conservative framework. Our results demonstrate no significant morphological variation evident temporally and a small but statistically significant degree of shape variation geographically despite the proximity of the study localities. These findings suggest that an accurate quantitative exploration of morphospace may be an important source of evidence on environmental and climatic shifts and the resulting influence on animal morphology.  相似文献   
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Abstract

Saami circular sacrificial sites have been known for many years in northern Norway and northern interior Sweden. Oral or written sources regarding their origins are nevertheless lacking outside reindeer-herding areas. These circular features have now been documented in Swedish Bothnian coastal environments together with site complexes at elevations, suggesting that they were used during the Iron Age, medieval and historic periods. It is argued that these coastal features, stone circles or ring-shaped enclosures, are Saami sacrificial sites of the same character as documented in North Norway and in the mountains and the forest lands of northern Sweden.  相似文献   
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The public opinion and the scientific community incorrectly believe that the English term “lunatic” was originally related only to insanity, but it also referred to epileptic people. The aim of this article is to clarify the original meaning of the English word “lunatic” by analyzing the evolution of the relationship between psychiatric and neurological diseases and by pointing out the influence of the moon in the history of medicine, in popular traditions, and in English literature. The article also contains a detailed and accurate review of the modern scientific literature on the relationship between moon and epilepsy/psychiatric disorders.  相似文献   
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A datum is considered spatial if it contains location information. Typically, there is also attribute information, whose distribution depends on its location. Thus, error in location information can lead to error in attribute information, which is reflected ultimately in the inference drawn from the data. We propose a statistical model for incorporating location error into spatial data analysis. We investigate the effect of location error on the spatial lag, the covariance function, and optimal spatial linear prediction (that is, kriging). We show that the form of kriging after adjusting for location error is the same as that of kriging without adjusting for location error. However, location error changes entries in the matrix of explanatory variables, the matrix of co‐variances between the sample sites, and the vector of covariances between the sample sites and the prediction location. We investigate, through simulation, the effect that varying trend, measurement error, location error, range of spatial dependence, sample size, and prediction location have on kriging after and without adjusting for location error. When the location error is large, kriging after adjusting for location error performs markedly better than kriging without adjusting for location error, in terms of both the prediction bias and the mean squared prediction error.  相似文献   
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Noel Castree 《对极》2002,34(1):111-146
This paper stages an encounter between two critical approaches that have been central to the recent "greening" of left geography. The theoretical and normative claims of the first approach, eco-Marxism, have been subject to sometimes biting criticism from advocates of the second approach, actor-network theory (ANT). Taking a nonorthodox Marxist perspective, I argue that the ANT critique of political economy approaches to nature is overstated and only partly defensible. By distinguishing between different modalities of eco-Marxism and ANT, I show the seeming standoff between the two approaches to society-nature relations to be false. Splitting the difference between a weak version of ANT and a relational version of eco-Marxism yields a political economy approach to socionature that arguably avoids the excesses of strong modalities of ANT and dualistic forms of eco-Marxism. By seeking to bridge the apparent gap between Marxism and ANT, the paper avoids reducing either approach to society-nature relations to one fixed position or theoretical-normative "essence". Instead, a particular modality of ANT is used to address the weaknesses of certain extant versions of eco-Marxism. The resulting synthesis offers conceptual tools with which Marxists can still critique a pervasive mode of human relationality to nature–namely, capitalist–while multiplying the actors and complicating the politics involved in approaching the society-environment nexus.  相似文献   
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