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   1334篇
  免费   398篇
  2023年   4篇
  2022年   2篇
  2021年   31篇
  2020年   28篇
  2019年   143篇
  2018年   116篇
  2017年   103篇
  2016年   126篇
  2015年   117篇
  2014年   111篇
  2013年   231篇
  2012年   131篇
  2011年   115篇
  2010年   88篇
  2009年   43篇
  2008年   69篇
  2007年   64篇
  2006年   44篇
  2005年   34篇
  2004年   29篇
  2003年   31篇
  2002年   21篇
  2001年   25篇
  2000年   20篇
  1999年   3篇
  1994年   1篇
  1993年   1篇
  1992年   1篇
排序方式: 共有1732条查询结果,搜索用时 15 毫秒
1.
The context of this paper is return visits to the homeland of labour migrants in Europe. The paper draws on data from the author's ethnographic fieldwork on the island of Guernsey and in Latvia during 2010–2012. By theorizing the relevance which the research participants attached to the phenomenon of corporeal co‐presence in relation to these visits, the paper bridges a timegeographic perspective with phenomenological interpretations. It explains how actual experience during the return path is influenced by both past trajectories and future anticipation. Return visits are conceptualized as spaces of encounter‐displacement and illustrated through examples of sensory and emotional experiences of anticipating for the return, the actual travel, time spent in the home area, and departure. The paper suggests that a focus on the body scale can help researchers to gain important insights into how the path is shaped through the corporeal experiences and how it shapes interpretations about home and possible future orientations.  相似文献   
2.
本文对青海古代各历史时期的文化遗址及文物进行了分析与探讨,提出了青海古代文化遗址有着分布的集中性、石器时代的完整性以及多元结构的民族文化特点;论证了以上特点是由地理环境及历史的各民族文化活动所致。  相似文献   
3.
Scientists advise limiting global warming to 1.5°C with substantial actions by 2030. Our viewpoint argues that climate response strategies in Canada have underemphasized and underestimated the potential contribution deep energy retrofits can make to greenhouse gas (GHG) emissions reductions, leading to inadequate responses in the building sector, and that Canada can (and should) be ambitious with building retrofits over the next decade. GHG savings from building retrofits can be realized more quickly than GHG reductions from other sectors, and either deliver net cost savings or are cost‐effective when compared to other mitigation measures. Retrofits can also provide social and economic benefits, such as improved health and comfort, and lower energy costs. This paper reviews energy use and building retrofits in Canada and argues the following should be implemented: (1) focus innovation on deep energy retrofit processes, not singular retrofit actions; (2) maximize both social and environmental benefits; (3) improve data gathering and availability for analysis and delivery; (4) innovate for a process of decisions and to avoid “dropouts” during the retrofit process; and (5) focus innovation on business models that maximize benefits.  相似文献   
4.
Using the Brazilian census and administrative panel data, the present paper provides evidence that the spatial concentration of analytical skills generates positive wage externalities for all workers in the local labor market. We rely on shift‐share instrumental variables to overcome the endogeneity of skill concentrations. The observed externality is independent from the classical market size economies. The estimates are robust to geography, institutions and workers' sorting on unobservable abilities.  相似文献   
5.
Elisa Pascucci 《对极》2021,53(1):260-278
Focusing on the design and production of the IKEA Foundation “Better Shelter” and on its use in a camp on the island of Lesvos, Greece, this article explores the role of logistical calculative rationales in the provision of emergency shelters to refugees. It argues that an engagement with the critical geographies of logistics contributes to the study of such “humanitarian goods” in two main ways. First, it foregrounds the technologies that allow emergency shelter products to circulate across production sites and disaster and border zones, and their connections to broader infrastructures and commercial networks in what recent literature has called “supply‐chain humanitarianism”. Second, a logistical lens highlights the disruptions that characterise the production and usage of emergency shelter products. The analysis adds to a body of work that exposes humanitarian technology and design as sites of friction, deeply embedded in global processes of bordering and accumulation.  相似文献   
6.
Nik Heynen  Megan Ybarra 《对极》2021,53(1):21-35
This introduction calls for political ecology to systematically engage with the ways that white supremacy shapes human relationships with land through entangled processes of settler colonialism, empire and racial capitalism. To develop the analytic of abolition ecology, we begin with the articulation of W.E.B. Du Bois’ abolition democracy together with Ruth Wilson Gilmore’s spatially attuned analytic of abolition geography. Rather than define communities by the violence they suffer, abolition ecologies call for attention to radical place‐making and the land, air and water based environments within which places are made. To that end, we suggest that an abolition ecology demands attention to the ways that coalitional land‐based politics dismantle oppressive institutions and to the promise of abolition, which Gilmore describes as making “freedom as a place”.  相似文献   
7.
This paper contributes to a critical methodological discussion that has direct ramifications for policy studies: how computational methods can be concretely incorporated into existing processes of textual analysis and interpretation without compromising scientific integrity. We focus on the computational method of topic modeling and investigate how it interacts with two larger families of qualitative methods: content and classification methods characterized by interest in words as communication units and discourse and representation methods characterized by interest in the meaning of communicative acts. Based on analysis of recent academic publications that have used topic modeling for textual analysis, our findings show that different mixed‐method research designs are appropriate when combining topic modeling with the two groups of methods. Our main concluding argument is that topic modeling enables scholars to apply policy theories and concepts to much larger sets of data. That said, the use of computational methods requires genuine understanding of these techniques to obtain substantially meaningful results. We encourage policy scholars to reflect carefully on methodological issues, and offer a simple heuristic to help identify and address critical points when designing a study using topic modeling.  相似文献   
8.
移动性是21世纪人文地理的研究热点和重要议题,它体现了空间科学的社会学转向,属于人文地理学的核心概念和中心命题,其中心性突出体现在它与其他传统和新兴的人文地理分支学科的交叉。本文以表格为工具梳理了地理移动性的研究理路,发现移动地理与其他人文地理分支学科共同聚焦的核心是:时间地理、旅游地理、行为地理的“时空行为”问题,政治地理、社会地理的“权力”“平等”“权利”问题,身体地理的“具身实践”“感官体验”问题,情感地理的“地方依恋”“身份认同”问题,想象地理的“地方感”问题,道德地理的“空间道德感”问题。本文识别这些关键问题为移动地理的“核心要素”,搭建移动地理的框架和体系,指出探查这些要素之间相互作用机制和不同时空移动类型的转化机理是未来移动性的研究方向。根据移动的空间尺度和时间强度,构建了包括日常移动、旅游和旅行移动到永久性移动在内的地理学移动性连续轴类型,并探索了移动地理研究的方法论体系。  相似文献   
9.
This article explores the articulation—in different forms, at different periods, and by different actors—of ‘national self‐determination’ in Somalia and across the Somali‐speaking regions of the Horn of Africa. It explores how this concept can be understood in the context of protracted political fragmentation in Somalia—considering unresolved debates over the ideological foundations of state reconstruction, disagreements about the suitability of federalism, aspirations for the recognition of an independent Republic of Somaliland, and the distinctive trajectory of the Somali Regional State in Ethiopia. Taking a comparative, cross‐border and wide‐angled historical approach, the article argues that ideas of an ethno‐linguistically, culturally and religiously defined Somali ‘nation’ continue to coexist (and be reproduced, updated and used) within an environment of extreme political fragmentation and across multiple ‘state’ boundaries. This argument is made through comparative analysis of contemporary examples of the performance of Somali state and nationalist identities within and beyond the region and the distinctive transnational Somali‐language media environment within which these ideas circulate and compete.  相似文献   
10.
The bodies and glazes of 27 early Western Zhou proto‐porcelain samples from Yejiashan cemetery, Hubei Province, were analysed using LA‐ICP–AES, SEM, XRD, a thermal expansion instrument and other analytical methods. The results indicated that the bodies of all samples were characterized by high silicon and low aluminium, and were made with porcelain stone raw materials found in the south of China. The glazes are typical of high‐temperature calcium glazes of the CaO (MgO) – K2O (Na2O) – Al2O3 – SiO2 series, with relatively high Mn and P content, which was probably caused by the addition of plant ashes. The physical properties and phase compositions of Yejiashan proto‐porcelain show that firing processes were still in the early stages of development in ancient China. Multivariate statistical analyses indicated that Yejiashan proto‐porcelain might have come from the Deqing area, in Zhejiang Province. These results provide new archaeological evidence for research on issues related to material flow in the Western Zhou dynasty.  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