全文获取类型
收费全文 | 170篇 |
免费 | 4篇 |
专业分类
174篇 |
出版年
2024年 | 2篇 |
2021年 | 1篇 |
2020年 | 1篇 |
2019年 | 6篇 |
2018年 | 4篇 |
2017年 | 1篇 |
2016年 | 4篇 |
2015年 | 5篇 |
2014年 | 3篇 |
2013年 | 36篇 |
2012年 | 7篇 |
2011年 | 7篇 |
2010年 | 10篇 |
2009年 | 3篇 |
2008年 | 2篇 |
2007年 | 3篇 |
2006年 | 6篇 |
2005年 | 3篇 |
2004年 | 2篇 |
2003年 | 4篇 |
2002年 | 4篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 5篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1986年 | 7篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1971年 | 1篇 |
1958年 | 1篇 |
1957年 | 2篇 |
1950年 | 1篇 |
排序方式: 共有174条查询结果,搜索用时 0 毫秒
91.
92.
Pierre Lafortune Jason McCormick Patrick Terriault 《Journal of Earthquake Engineering》2013,17(3):383-399
Over the past decade, the use of shape memory alloys (SMAs) in passive control devices has been explored. Nevertheless, some aspects in regards to the cyclic behavior of SMAs and the effect of pre-straining need to be clarified. In this study, small-scale shake table tests have been performed to explore the effectiveness of SMA bracing systems as compared to steel bracing systems. The reduced-scale experimental results imply that SMAs used in braces are more effective in controlling the response of a steel frame compared with a traditional bracing system. A finite element model (FEM) of the frame is developed in order to compare the analytical results with the shake table tests. Further, the effect of pre-straining the SMA braces is evaluated through both experimental and analytical studies. The results show that pre-straining improves the performance of the frame compared to the nonpre-strained case. However, as the level of pre-straining increases above approximately 1.0% to 1.5%, the benefits of pre-straining decrease compared with low-to-moderate pre-strain levels. 相似文献
93.
Pierre Petit 《亚洲研究评论》2013,37(4):471-490
Following the 1975 revolution, the Laotian statesmen adopted a modernising discourse that targeted “backward” traditions as undesirable. But since the 1990s, authorities have mitigated this standpoint, distinguishing “good” from “bad” traditions according to their compatibility with the program of national development, and professing their will to (re)instate the former as suitable expressions of culture in a multi-ethnic nation. This is manifest everywhere from the National Constitution to TV shows and ethnic catalogues. This paper analyses the implementation of these principles through the case of the boun greh New Year festival, an invented ethnic tradition of the Khmou, the largest ethnic minority in Laos. The article demonstrates that this implementation has consequentially implied the adoption of a grammar of national ethnicity; that this official framework paradoxically allows the Khmou to articulate demands for better recognition of their group; and that this process does not mute expressions of “cultural intimacy” at variance with this matrix. The official frame of ethnicity has been eventually adopted by the Khmou, but this state effect has multiplied the layers of expressed ethnicity: it cannot be equated with a unilateral regimentation that would deprive the Khmou of their agency. 相似文献
94.
Pierre Losson 《International Journal of Cultural Policy》2013,19(1):20-39
In June 2010, a Ministry of Culture was created in Peru, raising many questions regarding the ability of this new administrative structure to effectively implement a comprehensive cultural policy, which has been lacking so far, for the Peruvian State has based its previous policies almost exclusively on the preservation of cultural heritage. The Ministry inherits the flaws of the National Institute of Culture, and must address various challenges: the improvement of heritage management; the inclusion of indigenous populations in a never established national identity; a renewed scheme of promotion of the arts and incentives to cultural industries. The article discusses possible policy options for the new ministry, evidences the needs for a renovation of bureaucratic culture within the ministry, for clarification in the objectives set to the Ministry and for more comprehensive data about cultural practices in Peru. 相似文献
95.
Pierre Voinchet Gongming Yin Christophe Falguères Chunru Liu Fei Han Xuefeng Sun Jean Jacques Bahain 《Geochronometria》2013,40(4):341-347
The ESR dating method requires to describe the evolution of the ESR signal intensities vs. increasing gamma doses, then to extrapolate the equivalent dose of radiation received by the sample since its deposition using mathematical fitting. The function classically used to describe the growth curves of ESR aluminium signal in quartz was recently discussed and challenged for Lower Pleistocene sediments. In the present work, some alluvial sediments sampled in Upper Pleistocene fluvial terraces of the Yellow River system (China) permit us to test the application of another extrapolation function (linear + exponential) recently proposed for Lower Pleistocene sediments. The equivalent doses obtained here for the recent deposits of the Yellow River system and the corresponding ages are promising and indicate the potential of ESR to date quartz deposits from Upper Pleistocene times. 相似文献
96.
Agnès Lauriat-Rage René-Pierre Carriol Pierre Lozouet André Giret Hervé Leyrit 《Alcheringa: An Australasian Journal of Paleontology》2013,37(2):275-287
A sedimentary deposit discovered at Kerguelen Islands in 1988 is interbedded in the Cape MacLear cliffs, near Mont Rond (Ronarc'h Peninsula). The age of this oceanic deposit is considered to be lower to middle Miocene as indicated by isotopic dating of both the underlying and overlying basalts. This deposit yields a fauna essentially consisting of molluscs (bivalves, gastropods) and crustaceans (cirripedes). This fauna exhibits some similarities to Miocene to Recent austral faunas (New Zealand, Argentina) as a result of the establishment of the Antarctic Circumpolar Current. However, it has no species in common with the extant Kerguelen fauna. The Mont Rond fossil assemblage is best compared with either of two types of extant communities developed on a bare sandy sea floor where infaunal species are dominant, but most likely to an opportunistic one in depths from approximately 10 to 80 m. 相似文献
97.
Pierre Filion 《The Canadian geographer》2024,68(1):12-23
The article is a critical review of the literature investigating the impact suburbanization has had since the mid-20th century on the downtowns of Canadian mid-size cities and the strategies deployed to revitalize these districts. It demonstrates that large city downtowns are more likely than their mid-size city counterparts to enjoy conditions favourable to their success, hence the need to devise revitalization efforts tailored to the reality of mid-size city downtowns. The article identifies revitalization strategies adopted over the last decades, which mostly failed to reverse the decline affecting these downtowns. It then concentrates on the present, and likely enduring, revitalization model, which emphasizes hospitality, recreation, culture, services, and walkability. The article refines the understanding of the differences between mid-size and large city downtowns by concentrating on their specific dynamics and explores future revitalization options for mid-size city downtowns. It discusses the present and likely enduring absence of alternatives to the present revitalization model and highlights its equity downsides as it challenges the downtown low-income resident living environment. 相似文献
98.
99.
William E. Banks Francesco d'Errico A. Townsend Peterson Marian Vanhaeren Masa Kageyama Pierre Sepulchre Gilles Ramstein Anne Jost Daniel Lunt 《Journal of archaeological science》2008
We apply eco-cultural niche modeling (ECNM), an heuristic approach adapted from the biodiversity sciences, to identify habitable portions of the European territory for Upper Paleolithic hunter-gatherers during the Last Glacial Maximum (LGM), circumscribe potential geographic extents of the Solutrean and Epigravettian technocomplexes, evaluate environmental and adaptive factors that influenced their distributions, and discuss this method's potential to illuminate past human–environment interaction. Our ECNM approach employed the Genetic Algorithm for Rule-Set Prediction (GARP) and used as input a combination of archaeological and geographic data, in conjunction with high-resolution paleoclimatic simulations for this time frame. The archaeological data consist of geographic coordinates of sites dated by Accelerator Mass Spectrometry to the LGM and attributed to the Solutrean and Epigravettian technocomplexes. The areas predicted by ECNM consistently outline the northern boundary of human presence at 22,000–20,000 cal BP. This boundary is mainly determined by climatic constraints and corresponds well to known southern limits of periglacial environments and permafrost conditions during the LGM. Differences between predicted ecological niches and known ranges of the Solutrean and Epigravettian technocomplexes are interpreted as Solutrean populations being adapted to colder and more humid environments and as reflecting influences of ecological risk on geographic distributions of cultures. 相似文献
100.