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   30篇
  免费   1篇
  2020年   1篇
  2019年   3篇
  2016年   2篇
  2015年   2篇
  2014年   1篇
  2013年   5篇
  2012年   3篇
  2011年   1篇
  2010年   2篇
  2008年   3篇
  2007年   1篇
  2005年   3篇
  2003年   1篇
  2002年   1篇
  2000年   1篇
  1976年   1篇
排序方式: 共有31条查询结果,搜索用时 15 毫秒
1.
2.
3.
Tie-rods are essential structural elements, which have been employed for centuries in masonry historical buildings, either during the construction or in successive strengthening interventions, with the aim of containing dangerous horizontal actions. The actual work conditions of these tie-rods, which are strongly influenced by their load history, are difficult to be quantified theoretically, and an effective method for their measure is of great importance in order to ensure the efficiency of these elements during the time and the stability of the entire building. Common measurements are often carried out adopting models based upon significant simplifications, like, for example, hinges at the extremities. These assumptions, rarely represent the real work conditions for anchorages. In this work, a non-destructive testing method is presented, based upon sophisticated dynamical models that can take into consideration many of the circumstances neglected by the simplified models. Four case studies are extensively described, trying to embrace the most common situations in term of peculiar features of the building, structural configuration, and load history. The discussion of the results yields the safety margin of the rod with respect to the material failure and provides important indications about the overall stability of the whole building.  相似文献   
4.
ABSTRACT

We analyse the gender composition of the highest hierarchical levels within large Italian firms and we investigate whether it correlates to the working career of women in lower ranks of the same firm. We observe a disproportionate share of men hired and promoted, regardless of the top ranks’ gender composition. However, we detect a mitigating effect when the presence of women in higher managerial ranks increases promotions of women in lower ranks. This is consistent with the “women helping women hypothesis”. However, this mitigating effect is far from rebalancing career chances by gender. No significant differences emerge between firms in innovative and traditional sectors, despite the quite different narrative put in place by HR managers.  相似文献   
5.
6.
Infrared spectrometry is a well-established method for the identification of minerals. Due to its simplicity and the short time required to obtain a result, it can be practiced on-site during excavation using portable infrared spectrometers. However, the identification of a mineral may not be sufficient. For example, a lime plaster floor and a crushed chalk surface have a similar appearance and are composed of the same mineral – calcite. Here we exploit differences in the infrared spectra of geogenic, biogenic and pyrogenic calcites for the identification of each calcite type. The infrared calcite spectrum has three characteristic peaks in the region of 400–4000 cm−1, designated ν2, ν3, and ν4. When a calcite sample is ground, as part of the measurement preparation procedure, some grinding dependent changes will be revealed in the infrared spectrum. With additional grinding, the ν3 peak narrows and the heights of the ν2 and ν4 peaks decrease, when both are normalized to the ν3 height. By plotting the normalized heights of the ν2versus the ν4 of several grindings of the same sample, a characteristic trend line is formed for each calcite type. The trend lines of geogenic calcites have the shallowest slopes and highest ν4 values when compared to pyrogenic calcites, which can be further divided to ash and plaster/mortar samples. This method can assist in distinguishing between the various calcites, and provide insights into homogeneity and preservation state of the calcitic materials in question.  相似文献   
7.
8.
The archaeological reconstruction of ancient states requires consistent regional measures of state-directed power and influence. This paper presents data from a series of systematic archaeological surveys in the Cusco region of highland Peru to evaluate patterns of influence by the Wari state during a period of colonization from ca. AD 600–1000. We discuss interpretive debates over the nature and intensity of Wari social power, suggesting that site-based studies can be contextualized meaningfully using our large-scale dataset, which offers settlement patterns at varying distances (0–70 km) from Pikillacta, a Wari administrative center. We discuss local settlement patterns before and during Wari colonization, as well as the distribution of Wari pottery and local Wari-influenced wares. We then use a geographic information systems analysis of travel time from key sites to evaluate the broad regional distribution patterns of local and Wari ceramic styles. Although the regional survey data do not inform us reliably about all kinds of social power, we conclude that the Wari cultural, economic, and political influence over the Cusco region was limited and discontinuous—an example of colonization that resembles the practices of other early states.  相似文献   
9.
The drought-stricken Australian rural landscape, cultures of farming masculinity and an economy of value, moral worth and pride form a complex matrix of discourses that shape subjective dynamics that render suicide a possibility for distressed farmers. However, the centrality of a ‘mental health’ perspective and reified notions of ‘stoicism’ within this discursive field operate to exclude consideration of the ways in which cultural identity is linked to emotions. To illuminate and explore complex connections between subjectivity, moral worth and affect in relation to understanding farmer suicide, this article draws on theory and literature on agrarian discourses of masculine subjectivity and shame to analyze empirical data from interviews with farmers during times of environmental, social and economic crisis. The idealized notion of the farming man as ‘Aussie battler’ emerges from romantic agrarian mythology in which pride and self-worth are vested in traditional values of hard work, struggle and self-sacrifice. However, the structural context of agriculture, as it is shaped by the political economy of neoliberalism, threatens farm economic viability and is eroding the pride, self-worth and masculine identity of farmers. The article suggests that the notion of the ‘fallen hero’ captures a discursive shift of a masculinity ‘undone’, a regress from the powerful position of masculine subjectivity imbued with pride to one of shame that is of central importance to understanding how suicide emerges as a possibility for farmers.  相似文献   
10.
This paper describes the 3D modelling of Pinchango Alto, Peru, based on a combination of image and range data. Digital photogrammetry and laser scanning allow archaeological sites to be recorded efficiently and in detail even under unfavourable conditions. In 2004 we documented Pinchango Alto, a typical site of the hitherto poorly studied Late Intermediate Period on the south coast of Peru, with the aim of conducting spatial archaeological analyses at different scales. The combined use of a mini helicopter and a terrestrial laser scanner, both equipped with a camera, allowed a fast yet accurate recording of the site and its stone architecture. In this paper we describe the research background, the 3D modelling based on different image and range data sets, and the resulting products that will serve as a basis for archaeological analysis.  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