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   256篇
  免费   15篇
  2023年   1篇
  2022年   5篇
  2021年   2篇
  2020年   5篇
  2019年   8篇
  2018年   19篇
  2017年   18篇
  2016年   14篇
  2015年   11篇
  2014年   14篇
  2013年   63篇
  2012年   6篇
  2011年   12篇
  2010年   7篇
  2009年   8篇
  2008年   4篇
  2007年   3篇
  2006年   1篇
  2005年   6篇
  2004年   7篇
  2003年   2篇
  2002年   4篇
  2001年   4篇
  2000年   3篇
  1999年   1篇
  1998年   4篇
  1997年   4篇
  1996年   1篇
  1995年   4篇
  1994年   2篇
  1993年   2篇
  1992年   4篇
  1991年   2篇
  1990年   3篇
  1989年   2篇
  1988年   5篇
  1987年   4篇
  1985年   1篇
  1981年   3篇
  1979年   1篇
  1969年   1篇
排序方式: 共有271条查询结果,搜索用时 15 毫秒
31.
Der letzte Bericht des Intergovernmental Panel on Climate Change (IPCC 2007) erl?utert die weltweiten Auswirkungen des Klimawandels deutlich – allerdings aus globaler Sicht. Um zu kl?ren wie sich das regionale Klima in ?sterreich ver?ndern wird, wurde mit dem Projekt „reclip:more“ (Research for Climate Protection: Model Run Evaluation) eine erste kleinr?umige Datenbasis für Klimaschutz und Klimafolgenforschung für ?sterreich generiert. Klimaszenarien wurden mittels regionaler Klimamodelle (RCMs) für die Alpen als 10 × 10-Kilometer-Raster und mit anschlie?endem Downscaling für ?sterreich mit einer Zielaufl?sung 1 km entwickelt. Die RCMs wurden mit ERA-40 Reanalyse-Daten der Vergangenheit und Daten eines Zukunftsszenarios des globalen Klimamodells (GCM) ECHAM5 angetrieben, um retrospektive (1981 bis 1990) und künftige (2041 bis 2050) Klimadatens?tze für die Alpen zu berechnen und M?glichkeiten und Unsicherheiten der Modelle und Downscaling-Methoden für die Alpen zu evaluieren. Die nun vorliegenden Datens?tze und weitere, die im Folgeprojekt „reclip:century“ für alternative Treibhausgasszenarien bis 2100 berechnet werden, dienen dazu als Basis für Aussagen über ?kologische und sozio?konomische Entwicklungen im Hinblick auf den Klimawandel.  相似文献   
32.
This article questions the participatory dimension of urban governance in Mumbai. Based on surveys of a number of participatory projects for urban services, it compares the differentiated impacts of participation in middle‐class colonies with those in slums. Results demonstrate that changing citizen–government relationships have led to the empowerment of the middle and upper middle class who harness the potential of new ‘invited space’ to expand their claims on the city and political space. In contrast, the poor end up on the losing side as NGOs function more as contracted agents of the State than as representatives of the poor. Direct community participation empowers influential community members, small private entrepreneurs and middlemen, and contributes to labour informalization. Ultimately, these processes consolidate a form of ‘governing beyond the State’ that promotes a managerial vision of participation and leads to double standards of citizenship.  相似文献   
33.
18th century philosophers analyzed art through the aesthetic experience of the audience. By contrast, Adam Smith was interested in the moral judgment that an impartial audience may formulate. How can art and morality, the beautiful and the good, be combined into one analytical framework? Art and morality convey non-transcendental values that are intrinsic to human experience. With the aesthetic experience of the audience, art is used, and ultimately depends on the ways that humans relate to works or art and to the beautiful.  相似文献   
34.
This paper draws on Wobst’s concerns ideas of material culture, style and the implications of contemporary archaeology. In a socially engaged “archaeology of now”, I examine the spatiality and material culture of asylum seekers in Irish society as the Irish State governs and thus engineers their social and physical space. Housed in State-operated accommodation centers around the country, the spatial governance of asylum seekers in Ireland creates a structured, exclusionary transnational landscape of difference. The State thereby controls the movement, social borders, place, identity and social relations of asylum seekers in a newly global Ireland.  相似文献   
35.
36.
37.
While it is generally agreed that food processing has had a role in human evolution, the specific ways that is has affected our evolution are not well understood. Using a Niche Construction Theory (NCT) perspective, coupled with methodologies borrowed from “post-harvest” research in the plant sciences, this paper investigates the means and mechanism by which food processing is of evolutionary consequence. The central tenet of NCT is that organisms have an active role in their own evolution through reciprocal interactions with their environments; niche construction is understood to occur when organisms initiate long-term changes to their environments that modify the selection pressures on themselves and their descendants (and on other organisms in the environment). Humans and our hominin ancestors are considered to be the ultimate niche constructors due to our ability to modify selection pressures through diverse culturally generated and transmitted cultural means, i.e. cultural niche construction. In this paper, post-harvest methods are used to identify how food processing could feasibly have permitted hominins to modify their evolutionary selection pressures. Food processing is shown to facilitate access to increasing amounts of digestible nutrients and energy (kilocalories/kilojoules) as well as promoting increased dietary breadth and making possible the production of safer and more stable foods. It is argued that these advancements catalysed related technological and ecological skills and knowledge, which together with the nutritional benefits, further triggered changes in hominin brain and body and locomotory adaptations and increased longevity, disease prevention and juvenile survival rates.  相似文献   
38.
We present a scheme to modify empirical Green's functions by attenuation considering: (1) geometrical spreading; (2) decay in high frequency; (3) regional attenuation; and (4) phase of the signal. The accelerograms computed with the proposed simulation method are compared, in time and frequency domains, with strong ground motions from subduction and intermediate-depth earthquakes recorded in Mexico. It is shown that this simple empirical Green's functions technique can synthesize both the shape and amplitude of the response spectra in the site, considering a postulated seismic source located at different distances from the original one.  相似文献   
39.
This article proposes a damage index for the seismic analysis of Reinforced Concrete members using the hysteretic energy dissipated by a structural member and a drift ratio related to failure in the structure. The index was calibrated against observed damage in laboratory tests of 76 RC column units under various protocols. Values obtained in this calibration had acceptable agreement with the levels of damage observed in the test specimens. An analysis of the parameters involved in the definition of the proposed damage index shows the importance of displacement history in the drift ratio capacity of structures.  相似文献   
40.
This article presents a numerical study aimed at improving effectiveness of the isolation system of an actual building by adding magneto-rheological (MR) dampers that act in parallel to the existing rubber bearings (RB). The building itself is modeled with uniaxial elastic elements. Additional elements that include the RBs and the MR dampers are added at the base of the building and two different genetic algorithms are used to optimize operation of the MR dampers. Maximum acceleration and relative displacement at the top of the building are taken as the variables to be minimized. Records of destructive earthquakes are used as input. A comparison is made between the building responses with RB and the one with the additional control system.  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