首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   161篇
  免费   5篇
  2023年   6篇
  2022年   3篇
  2021年   3篇
  2020年   5篇
  2019年   12篇
  2018年   8篇
  2017年   12篇
  2016年   10篇
  2015年   9篇
  2014年   5篇
  2013年   16篇
  2012年   11篇
  2011年   9篇
  2010年   11篇
  2009年   6篇
  2008年   4篇
  2007年   7篇
  2006年   6篇
  2005年   2篇
  2004年   2篇
  2003年   3篇
  2002年   2篇
  2001年   1篇
  2000年   3篇
  1999年   1篇
  1998年   1篇
  1997年   1篇
  1996年   1篇
  1995年   2篇
  1993年   2篇
  1983年   1篇
  1980年   1篇
排序方式: 共有166条查询结果,搜索用时 15 毫秒
1.
周滔  张璞洁 《人文地理》2023,38(1):118-129+157
乡村振兴要求走乡村内生性发展道路,客观认知乡村发展能力的时空分异格局和交互关系对乡村振兴战略实施具有重要意义。本文从农业产业发展、农村基础建设和农民社会生活三个维度构建测度指标体系,并引入面板向量自回归模型识别影响乡村发展能力的敏感因素,以此测度乡村发展能力指数,进而采用探索性时空数据分析方法揭示乡村发展能力的时空交互特征。结果表明:(1)我国中部地区多维乡村发展能力提升,但呈明显的空间异质性,不同维度间差异化显著;(2)中部地区多维乡村发展能力局域空间格局呈现较强的动态性并整体表现出较强的空间依赖关系;(3)邻接地级市多维乡村发展能力的时空交互网络以正向关联为主,局部空间呈差异化的竞合态势。  相似文献   
2.
Knowledge about the Inca measurement system is based on information from the colonial chronicles and modern studies of the 16th-century Quechua dictionaries. Based on those texts, we can presume that the Incas used an anthropometric system of measurement adopted from the proportions of the human body. Using cosine quantogram analysis and statistical verification, it is possible to verify the existence of the measurement system used by the Inca architects. For this purpose, a measurement series of architectural and water infrastructure elements were collected from 3D point cloud of the Chachabamba and Machu Picchu settlements in Machupicchu National Archaeological Park.  相似文献   
3.
This study aims to provide a comprehensive examination of the evolution of regional science, a scholarly domain in the social sciences that applies analytical and quantitative approaches and methods to understand and address urban, rural, or regional problems. We conducted a bibliometric analysis of 8509 articles published in six regional science flagship journals (including the Journal of Regional Science, Annals of Regional Science, Regional Science and Urban Economics, Papers in Regional Science, Regional Science Policy and Practice, and International Regional Science Review) from 1958 to 2021. The analysis presents an objective data-driven and unprecedented visualization of the field's intellectual, social, and conceptual structure and trends from the beginning to the present. It also provides a rich portrayal of the epistemology of regional science and illuminates matters related to regional science education and training. We find that regional science has moved well beyond its origins, shifting away from a heavy focus on theory and abstraction to modeling/simulation, empirical analysis, and policy research. We also find that there has been increasing attention to “people” in regions and the spatial characteristics of social problems, and some important shifts in the regional science community itself, particularly in terms of patterns of collaboration and the geography of scholarship. The findings of this paper provide implications for future directions of research and education for regional science.  相似文献   
4.
The fossil record suggests that modern human morphology evolved in Africa between 150,000 and 50,000 years ago, when the sole inhabitants of Eurasia were the Neanderthals and other equally nonmodern people. However, the earliest modern or near-modern Africans were behaviorally (archaeologically) indistinguishable from their nonmodern, Eurasian contemporaries, and it was only around 50,000-40,000 years ago that a major behavioral difference developed. Archaeological indications of this difference include the oldest indisputable ornaments (or art broadly understood); the oldest evidence for routine use of bone, ivory, and shell to produce formal (standardized) artifacts; greatly accelerated variation in stone artifact assemblages through time and space; and hunting-gathering innovations that promoted significantly larger populations. As a complex, the novel traits imply fully modern cognitive and communicative abilities, or more succinctly, the fully modern capacity for Culture. The competitive advantage of this capacity is obvious, and preliminary dates suggest that it appeared in Africa about 50,000 years ago and then successively in western Asia, eastern Europe, and western Europe, in keeping with an African origin. Arguably, the development of modern behavior depended on a neural change broadly like those that accompanied yet earlier archaeologically detectable behavioral advances. This explanation is problematic, however, because the putative change was in brain organization, not size, and fossil skulls provide little or no secure evidence for brain structure. Other potential objections to a neural advance in Africa 50,000-40,000 years ago or to the wider Out-of-Africa hypothesis, include archaeological evidence (1) that some Neanderthals were actually capable of fully modern behavior and (2) that some Africans were behaviorally modern more than 90,000 years ago.  相似文献   
5.
ABSTRACT

Geographers interested in how entrepreneurs perceive locational environments have studied their mental maps in several European countries, within the theoretical framework provided by behavioral approach. Such studies have typically employed quantitative techniques, but qualitative studies are relatively new to this line of research. In this article, I examine the mental maps of entrepreneurs in Italy by using a mixture of qualitative and quantitative methods. I present and discuss the qualitative outcomes of this research, focusing in particular on the explanatory location factors and the key influences on the mental maps of entrepreneurs. What emerges is the realization that entrepreneurs are far from being fully rational economic actors, who exploit optimally all information and who are driven only by objective considerations. Rather, their views are also affected by subjective factors, individual’s own insights, commonplaces, stereotypes, and prejudices, particularly with reference to the southern regions of Italy (Mezzogiorno), and of other peripheral areas.  相似文献   
6.
许多出土饱水木质文物因其降解严重、含水率较高,容易在脱水过程中出现不可逆的收缩变形以及开裂现象,从而遭到严重破坏。因此,饱水木质文物脱水方法的研究是文物保护工作中的重要课题。为探究风冷冷冻法对饱水木质文物脱水的效果,以一批无法复原的出土饱水木质文物为研究对象,在对其材种、含水率、基本密度及化学成分进行了测定和分析后,使用一台风冷电冰箱在-18℃条件下对样品进行了风冷干燥脱水处理,记录脱水时间和脱水效果,并分析了该方法的传质传热特点,证明了风冷干燥法用于饱水木质文物的脱水干燥能够取得良好效果,并且具有对文物干预小、适用性广、操作简便、成本低廉等优点,为饱水木质文物的脱水处理提供了一种新的思路。  相似文献   
7.
The restoration of paintings on elements in cultural heritage buildings (fundamentally, churches) involves two structural problems: capturing the geometry of the construction element and its development. In many cases, the geometries are regular (e.g., cylinders, spheres, elliptical domes). However, there are cases in which the elements cannot be adapted to any known geometry, much less one that can be mathematically developed. The development of surfaces becomes essential for the restoration of paintings over “flat elements” (over which work is performed on the ground) that are subsequently transferred to the real surface (ceilings). The mathematical transformations that allow regular geometries to be developed are widely known (cartographic projections). However, when the geometry is irregular, there is no development. This study presents a new methodology based on differential rectification and its application for the development of oculi in the Los Santos Juanes Church (Valencia), whose geometry is completely irregular both in shape and as a result of construction defects (and damage caused by fire). The present study focuses on the restoration of paintings damaged by fire.  相似文献   
8.
Students training to become primary school teachers appear to have little awareness of the core concepts of geography (teaching). To ensure that future primary school teachers are able to develop their pupils’ geographical awareness, a six weeks programme was developed. The characteristics of this programme – named Consciously Teaching Geography (CTG) – are: principles of good geography teaching, conjunction and a recurrent structure during training, modelling and reflection. In a quasi-experimental research design the question is answered what the effects are of CTG on the development of pedagogical content knowledge (PCK) for the subject of geography of first year primary student teachers. The results indicated that the programme has a positive effect on the domain-specific PCK development in the short term.  相似文献   
9.
Tie-rods are essential structural elements, which have been employed for centuries in masonry historical buildings, either during the construction or in successive strengthening interventions, with the aim of containing dangerous horizontal actions. The actual work conditions of these tie-rods, which are strongly influenced by their load history, are difficult to be quantified theoretically, and an effective method for their measure is of great importance in order to ensure the efficiency of these elements during the time and the stability of the entire building. Common measurements are often carried out adopting models based upon significant simplifications, like, for example, hinges at the extremities. These assumptions, rarely represent the real work conditions for anchorages. In this work, a non-destructive testing method is presented, based upon sophisticated dynamical models that can take into consideration many of the circumstances neglected by the simplified models. Four case studies are extensively described, trying to embrace the most common situations in term of peculiar features of the building, structural configuration, and load history. The discussion of the results yields the safety margin of the rod with respect to the material failure and provides important indications about the overall stability of the whole building.  相似文献   
10.
Colour measurements and non‐destructive μ‐X‐ray mappings have been used for the first time in a comprehensive study of medieval émail champlevé works from different production areas in France and Germany. This approach has given a new insight into the enamel powder preparation process of the glass material used for enamelling. Colour measurements demonstrated that all production centres used glass of very similar hues, but with large differences in colour saturation. The μ‐X‐ray mapping results of blue enamels are described by a semi‐qualitative approach. Significant variations in oxide contents of lead, cobalt, manganese and antimony oxides were found. The variations suggest that more than one glass material was used to prepare the powder for enamelling. The variations in antimony and cobalt show that glass had different degrees of opacity and colour depth. The manganese and lead contents, which do not correlate with the cobalt or antimony contents, indicate that probably glass of different base compositions was used to prepare the enamel powder for one champlevé field.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号