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   158篇
  免费   3篇
  161篇
  2024年   2篇
  2023年   4篇
  2021年   3篇
  2020年   4篇
  2019年   7篇
  2018年   21篇
  2017年   19篇
  2016年   15篇
  2015年   11篇
  2014年   4篇
  2013年   27篇
  2012年   4篇
  2011年   5篇
  2010年   5篇
  2009年   4篇
  2008年   3篇
  2007年   3篇
  2005年   1篇
  2004年   1篇
  2003年   2篇
  2002年   3篇
  2001年   1篇
  2000年   3篇
  1999年   2篇
  1997年   2篇
  1989年   2篇
  1986年   1篇
  1984年   1篇
  1983年   1篇
排序方式: 共有161条查询结果,搜索用时 15 毫秒
41.
After two turbulent years in which different pathways for the future of the political and institutional framework of Portugal clashed, the country began a process of consolidation of the democratic institutions delineated between 1975/6. However, the role played by the military in the fall of the previous dictatorial regime and the fragility of the new democratic institutions did not allow their immediate withdrawal from political life. The President of the Republic was a military man and the political parties had agreed to maintain an unelected sovereign body, the Council of the Revolution, which only dissolved in 1982. Based on primary sources that only recently became available, this article presents some elements that help to understand the success of democratic consolidation in Portugal. This long process should not be interpreted as a confrontation between civilians, desirous to put an end to military tutelage, and the military, who at all costs sought to keep their privileges. The dividing line should be placed between those who defended the maintenance of the status quo, and the supporters of military subordination to the civil power.  相似文献   
42.
    
ABSTRACT

Although many experimental tests and numerical models are available in the literature, the numerical simulation of the seismic response of existing masonry buildings is still a challenging problem. While the nonlinear behavior of masonry structures is reasonably predictable when the out-of-plane behavior can be considered inhibited, when the in-plane and out-of-plane responses coexist and interact, simplified models seem unable to provide reliable numerical predictions. In this article, taking advantage of the experimental tests carried out in a shaking table on two masonry prototypes at LNEC, a macro-element approach is applied for the numerical simulations of their nonlinear response. The adopted approach allows simulating the nonlinear behavior of masonry structures considering the in-plane and out-of-plane responses. Since it is based on a simple mechanical scheme, explicitly oriented to representing the main failure mechanisms of masonry, its computational cost is greatly reduced with respect to rigorous solutions, namely nonlinear FEM approaches. Two modeling strategies are adopted, namely a regular mesh independent from the real texture of the prototypes and a detailed one coherent with the units disposal. The numerical results are discussed and the correlation between the nonlinear static analyses and the dynamic response is provided.  相似文献   
43.
    
ABSTRACT

Earthquakes cause severe damage to masonry structures due to inertial forces acting in the normal direction to the plane of the walls. The out-of-plane behavior of masonry walls is complex and depends on several parameters, such as material and geometric properties of walls, connections between structural elements, the characteristics of the input motions, among others. Different analytical methods and advanced numerical modeling are usually used for evaluating the out-of-plane behavior of masonry structures. Furthermore, different types of structural analysis can be adopted for this complex behavior, such as limit analysis, pushover, or nonlinear dynamic analysis.

Aiming to evaluate the capabilities of different approaches to similar problems, blind predictions were made using different approaches. For this purpose, two idealized structures were tested on a shaking table and several experts on masonry structures were invited to present blind predictions on the response of the structures, aiming at evaluating the available tools for the out-of-plane assessment of masonry structures. This article presents the results of the blind test predictions and the comparison with the experimental results, namely in terms of formed collapsed mechanisms and control outputs (PGA or maximum displacements), taking into account the selected tools to perform the analysis.  相似文献   
44.
45.
46.
Evacuation planning is an important component of emergency preparedness in urban areas. The number and location of rescue facilities is an important aspect of this planning, as is the identification of primary and secondary evacuation routes for residents to take. This article introduces a multiobjective approach to identify these aspects of evacuation planning. The approach incorporates a multiobjective model into a geographical information systems–based decision support system that planners can access via the Internet. The proposed approach is demonstrated with a case study for the City of Coimbra, Portugal, for evacuation during major fires. Although presented in this context, this approach is applicable to other emergency situations such as earthquakes, floods, and acts of terrorism.  相似文献   
47.
Lost after partial destruction by dredging in 1970, Arade 1 was a priority for the Centro Nacional de Arqueologia Náutica e Subaquática (CNANS). The upper part of the hull, lying over a 7-m-long area of the bed of the Arade river, was fully observed and recorded during the first two seasons (2001 and 2002) and dismantled in a third phase (2003). The 2004 and 2005 seasons aimed at the excavation, full recording and dismantling of the lower hull, briefly observed at the end of 2002. This second, detached, portion of the hull, was buried in the sediment and corresponds to midships.
© 2008 The Authors  相似文献   
48.
The article examines Vidas secas (1938) by Brazilian writer Graciliano Ramos as bridging biopolitical reflections on animality and new materialist reflections on animal studies. By tracing the bond between canine and human in Vidas secas as a canine melancholia, from Lacanian extimité into Donna Haraway’s species companionship, I expose the implicit theory of animality of the novel as an interspecies politics of survival. In doing this, I present a new frame of interpretation for the novel that places its particular kind of melancholia as untimely contemporary.  相似文献   
49.
50.
This study examines the potential socio-spatial impacts of a new series of marine protected areas (MPAs) on fishers in Moorea, French Polynesia. The establishment of the MPAs is contextualized within recent and historical processes of economic development and theories of women in development and gender, culture and development. Seventy adults from three neighborhoods in Moorea were interviewed. Analysis of the data provides new information about the characteristics of fishing in Moorea. Unlike most fishing cultures and communities throughout the Pacific Islands, men and women in Moorea have similar, as opposed to segregated, spatial patterns of fishing activities and fishing methods. The study also points out the potential negative impacts of the MPAs on both men and women, particularly younger and lower-income fishers.  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