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   38篇
  免费   1篇
  2024年   2篇
  2023年   1篇
  2020年   2篇
  2019年   2篇
  2018年   5篇
  2017年   2篇
  2016年   3篇
  2015年   2篇
  2014年   2篇
  2013年   8篇
  2012年   2篇
  2011年   3篇
  2010年   1篇
  2009年   1篇
  2006年   2篇
  2002年   1篇
排序方式: 共有39条查询结果,搜索用时 171 毫秒
11.
12.
This article investigates the seismic performance of one-story reinforced concrete structures for industrial buildings. To this aim, the seismic response of two structural prototypes, a cast-in-situ monolithic frame and a precast hinged frame, is compared for four different levels of translatory stiffness and seismic capacity. For these structures an incremental nonlinear dynamic analysis is performed within a Monte Carlo probabilistic simulation. The results obtained from the probabilistic analysis prove that precast structures have the same seismic capacity of the corresponding cast-in-situ structures and confirm the overall goodness of the design criteria proposed by Eurocode 8, even if a noteworthy dependency of the actual structural behavior from the prescribed response spectrum is pointed out.

The experimental verification of these theoretical results is searched for by means of pseudodynamic tests on full-scale structures. The results of these tests confirm the overall equivalence of the seismic behavior of precast and cast-in-situ structures. Moreover, two additional prototypes have been designed to investigate the seismic behavior of precast structures with roof elements placed side by side. The results of these further tests show that an effective horizontal diaphragm action can be activated even if the roof elements are not connected among them, and confirm the expected good seismic performance of these precast systems. Finally, the results of the experimental tests are compared with those obtained from nonlinear structural analyses. The good agreement between numerical and experimental results confirms the accuracy of the theoretical model and, with it, the results of the probabilistic investigation.  相似文献   
13.
14.
This paper investigates the impact of the main criterion employed by the European Commission for the allocation of the largest portion of Structural Funds, based on the threshold of the 75% of European Union (EU) average gross domestic product (GDP) per capita. We focus on the 2014–2020 programming period and on EU-15 regions to analyze if this criterion has penalized some of them, as a consequence of the 2004 EU enlargement, which has represented an exogenous shock in the allocation process, due to the economic backwardness of new member states. Through the application of Synthetic Control Methods and Difference-in-Differences estimators at different geographical scales, we show that regions that did not obtain the less developed status in both the programming period 2007–2013 and 2014–2020, but that would have obtained it in the period 2014–2020 without the 2004 EU enlargement, experienced a significantly lower GDP per capita growth between −10.5% and −5.7%. Conversely, territories that in the period 2014–2020 lost the less developed status, previously obtained in the time frame 2007–2013, were not characterized by a significantly lower economic growth, providing some evidence of the effectiveness of the safety net.  相似文献   
15.
The practice of science usually involves more than a solitary genius in a solitary room, coping with the problem of her/his life. From the second half of the 19th century onwards, scientific research, especially in the field of the Natural Sciences, has grown into a more and more complex practice, which often entangles very special needs, in terms of research objects, techniques, sources, and perspectives. A few special places, such as the Stazione Zoologica di Napoli, have represented in this period the focal points of an ever growing international scientific network, promoting independent research, exchange and diffusion of novel practices and techniques and unrestricted confrontation. The so-called "Naples experience" has been cited by a large number of renowned scientists of the last two centuries as a key moment in their scientific life. Here we have tried to test it against the experience of three great scientists par excellence, i.e. three Nobel laureates (T. H. Morgan, Otto Warburg, J. D. Watson). The different experiences they have had at Naples represent, in our view, three different moments of the professional life of almost every scientist. Therefore, we have chosen to present them as a phenomenology. The final section is dedicated to a survey of the Zoological Station's contribution to neurosciences, especially to the Naples experience of the Nobel Prize winner Sir Bernard Katz and his assistant Ricardo Miledi, between 1965 and 1970. Their work on the squid at Naples allowed probing and quantitative refinement of results already obtained on different animals and contributed to reinforce the long lasting neurophysiological tradition of the institute.  相似文献   
16.
Stable isotope analysis of carbon (δ13C), nitrogen (δ15N) and sulphur (δ34S) were carried out on one of the largest assemblages of Late Upper Palaeolithic human remains in Southern Europe, at Grotta del Romito (Cosenza), Italy. The burials were stratigraphically dated from ca. 18,000 to 13,000 cal BP, which was confirmed by a series of new AMS dates made directly on the bone collagen. Dietary reconstruction from carbon and nitrogen stable isotopes revealed that eight of the nine individuals analysed, dating to the Final Epigravettian, had very consistent diets, rich in terrestrial animal protein, regardless of their age or sex. These included two individuals who were suffering from severe pathologies. A single individual, dating to the Evolved Epigravettian had a more variable diet, which was significantly enriched in protein from marine or freshwater fish compared to the later burials. Overall, the results are consistent with the very limited number of other studies which describe a change to more specialised and less variable subsistence strategies, in this case the hunting of large herbivores, towards the end of the Palaeolithic period. Sulphur isotope values of all of the nine burials and several faunal samples were notably consistent, showing no evidence of long-distance migration to the site from a different geological zone.  相似文献   
17.
One of the most important economic and social facts concerning the European Union consists in the mismatch among its regions in terms of unemployment rates. The paper aims at examining and measuring the efficiency of Italian policies for labour market carried out in the last 10 years, in terms of reduction in the regional disparities in comparison with the whole European distribution of unemployment. We question whether these policies have been successful or the territorial dimension has still a relevant role on the unemployment in Italy. We try to answer to this question by calculating the Theil Index using data from 1996 to 2006 on unemployment and participation from Eurostat at NUTS 2 level, comparing Italian data with those of other EU countries. Our results show that Italy has still a prominent role in the geographical disparities among regions and that its contribution to the geographical concentration of unemployment is still high (especially if we consider female and youth unemployment).  相似文献   
18.
The study of the various inspirations of Ludovico Geymonat's epistemology (positivism and neopositivism, neorationalism, historicism and dialectical materialism) illustrates the way in which for the Italian philosopher the problem of objectivity of knowledge remains inseparable from the historicity of the sciences. Geymonat's epistemological approach associates scientific progress to its objectivity.  相似文献   
19.
The scope and mission of the history of science have been constant objects of reflection and debate within the profession. Recently, Lorraine Daston has called for a shift of focus: from the history of science to the history of knowledge. Such a move is an attempt at broadening the field and ridding it of the contradictions deriving from its modernist myth of origin and principle of demarcation. Taking the move from a pluralistic concept of medicine, the present paper explores the actual and possible contributions that a history of knowledge can offer to the history of medicine in particular. As we will argue, the history of medicine has always been a history of knowledge, but for good reasons has always stuck to the concept of medicine as its object and problem throughout the ages, including the modern, scientific one. We argue that, in the history of medicine, the demarcation between scientific and non‐scientific represents an accident, but is not foundational as in the case of natural science. Furthermore, the history of medicine programmatically played a role in at least two academic domains (history proper and medical education), adjusting historical narratives of medical knowledge to its audience. Accordingly, we underscore that the history of both science and medicine, as traditionally defined, already provides room for almost the whole spectrum of approaches to history. Moreover, their different myths of origin can, and indeed must, be included in the reflexivity of the historical gaze. We argue that the position towards a history of science, medicine, or knowledge is not a question of narrative or theory, rather, it is a question of relevance and awareness of extant contexts.  相似文献   
20.
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