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101.
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This paper presents dental morphological data of Neolithic, Chalcolithic and Bronze Age populations from the Catalan Pre-Pyrenean area. The Neolithic group, in particular, differs from those of surrounding areas in its funerary culture: the building of cists, which is not present in the Sepulcres de Fossa Culture. A minimum number of 118 individuals from this area were studied for this work, and the data were compared with those of other Iberian and European groups. The results indicate that the two micro-regional groups from the Catalan area (Pre-Pyrenean and Pre-Coastal) were biologically different during the Neolithic and the Chalcolithic, but not in the Bronze Age, when they also appeared to be more homogeneous culturally. In addition, both areas differ biologically from coetaneous Italian groups, although those closer to the coast show slightly smaller differences. Finally, the Bronze Age groups also present fewer differences with regard to the Italian Bronze Age’s group. Therefore, the results suggest that the Catalan Neolithic population had two separate origins, related to cultural patterns, and that differences between the groups decreased within time, probably due to trade-related activities. Moreover, the fact that the difference with Italian populations decreased during the Bronze Age suggests major population movements through the Mediterranean that would affect the biological composition of the human groups.  相似文献   
103.
In a previous article, we presented an innovative method to analyze cut marks produced with metal tools on animal bones from a metrical and tridimensional perspective (Maté-González et al. 2015). Such analysis developed a low-cost alternative technique to traditional microscopic methods for the tridimensional reconstruction of marks, using their measurements and sections. This article presents the results of an experimental study to test this photogrammetric and morphometric method for differentiating cut marks generated with metal, flint, and quartzite flakes. The results indicate statistically significant differences among cut marks produced by these three types of raw material. These results encourage the application of this method to archeological assemblages in order to establish a link between carcass processing and lithic reduction sequences on different raw materials and also to define the kind of tools used during butchery.  相似文献   
104.
Chert from the limestones and marly limestones of Castelltallat Formation (Ebro Basin) was widely used throughout prehistoric times in north-eastern Iberia to produce stone tools due to its properties and accessibility. A rough estimate indicates that this rock—either as raw material or as lithic products—was distributed mainly to the north of the outcrops, over an area of 6000–8000 km2. However, other rocks in the area have similar characteristics which can lead to confusion in the interpretation of its prehistoric use and distribution. In order to establish useful archaeometric criteria for differentiating this chert from other similar, the Castelltallat chert is characterised in petrographic, mineralogical and geochemical terms. The chert nodules are found to be homogenous at the macroscopic and microscopic level, with a significant presence of bioclasts, thus indicating they might be formed in a freshwater lake environment by the early diagenetic replacement of carbonates in shallow waters. The mineralogical composition is homogeneously uniform and of a flint type, characterised by an almost exclusive predominance of quartz, without any opaline phases, and a variable proportion of moganite. The iron oxide content is very low, whereas its chemical composition is unusually high in uranium which correlates positively with carbonate content and negatively with silica. Archaeometrical parameters are provided to reach a proper identification of tools knapped with this chert. This way, chert from Castelltallat Formation turns out to be a valuable lithological marker to evaluate the range of mobility of the human groups who lived in the north-eastern Iberia and their contacts with neighbouring areas.  相似文献   
105.
ABSTRACT

Mainstream ecological thought is explored in three sections: (i) Epistemological traits. Given the typical scientific development and the necessity of preserving our intellectual heritage, the conservatism outlined in (i) is cyclical, so its stages are graphically summarized. (ii) Methodological benchmarks antithetically derived from (i), in order to get faster advancement consistent with the growing environmental challenges which spur ecological development. (iii) The renaissance of an old paradigm. This section exposes the misunderstanding of the physical concept of equilibrium by the mainstream ecological thought; this explains its current state. Consequently, section (iii) also summarizes the evolution of a recent set of proposals (organic biophysics of ecosystems) that rescues the foundational paradigm of ecosystem ecology based on physics, neglected by the mainstream thought before producing its most valuable results. We highlight that the main problems emerge from the weakness of integration between ecology, physics and epistemology, and spurious links between ecology and neoclassical economics.  相似文献   
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段娟 《当代中国史研究》2012,(6):100-109,128
三线建设是中国在中西部地区进行的一场以备战为指导思想,以交通、国防科技和基础工业为主体的大规模的基本经济建设。近20年来,关于三线建设决策的形成、实施、评价以及与当前西部大开发的关系等相关问题的研究,一直是学术界关注的热点,无论在文献资料的公布方面,还是在相关问题的研究方面,都取得了很大进展。通过梳理近20年来的研究成果,可看出目前的研究仍存在一些薄弱环节,需要学者们继续挖掘档案资料、拓宽研究视野、丰富研究方法,并开展国内外学术交流,以促进研究的进一步深入。  相似文献   
108.
ABSTRACT In this paper, we introduce a new spatially constrained clustering problem called the max‐p ‐regions problem. It involves the clustering of a set of geographic areas into the maximum number of homogeneous regions such that the value of a spatially extensive regional attribute is above a predefined threshold value. We formulate the max‐p ‐regions problem as a mixed integer programming (MIP) problem, and propose a heuristic solution.  相似文献   
109.
Regional policies seek to enable regions to increase their competitiveness and development, and as such one priority Objective of activities financed by Structural Funds is higher employment, higher productivity and economic activity. How efficiently the regions apply the funds is a fundamental issue for the development and continuity of regional policies. We therefore consider that determining the efficiency of European regional policies is an issue of high importance, and this is the main aim of this study. We have considered it appropriate to use the available information to apply a mathematical technique known as Data Envelopment Analysis (DEA), which allows us to calculate the technical efficiency and inefficiency of the Structural Funds applied in the Objective 1 regions for the period 2000–2006. Furthermore, we wish to determine if the regions have been more efficient in creasing their levels of employment or in increasing productivity. Our study applies this methodology along with other methods like regression analysis, profit analysis and factorial analysis to determine the variation in the rate of unemployment and productivity in these European Regions. The study reveals that only eight regions are efficient, although none of them is run in all the models.  相似文献   
110.
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