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排序方式: 共有169条查询结果,搜索用时 31 毫秒
101.
Research design can be elegant but rarely does good research embarking on a new and complex area travel in a straight line. This article briefly describes the winding journey of three investigators, two Kuwaitis, a sociologist and the other asocial work researcher, and one American psychologist. Their goal was to tale the emotional pulse of Kuwait in the shadows of fifteen years of Iraq‐induced trauma. Along the way they adopt an indigenous focus that lead them to invent a measure of Raha (wellbeing) especially suited for studying Kuwaitis. The latter portion of the paper describes the procedures and results of the development of the Kuwaiti Raha Scale, ending with a discussion of the implications for international research in the social sciences. This study was funded by the Kuwait Foundation for the Advancement of Science (KFAS).  相似文献   
102.
This article demonstrates how some contemporary scholars, operating from within the traditional Shiʿi establishment, have paved the way for new interpretations of Islam in general and Shiʿism in particular. To do so, the article focuses on three specific themes: the notion of the (im)purity of non-Muslims, rulings on apostasy and precepts related to women's rights. Following a brief explanation of the history of Shiʿism, the article addresses each of three aforementioned themes in turn. In each section, the article explains how the relevant theme was approached by earlier religious scholars, and how it has been treated differently by some contemporary reformist Shiʿi clerics. While not claiming the trends of thought instigated by some contemporary ʿulamāʾ are entirely homogeneous with liberal ideas about human rights, this article provides examples of Shiʿi legal standpoints being reformed to meet the challenges of the contemporary world.  相似文献   
103.
Microbial biofilms have developed on the surfaces and within the painted and gilded layers of mummy cartonnage at the Saqqara museum storeroom in Giza, Egypt. SEM–EDX, XRD and FT–IR–ATR techniques were applied to analyse the coloured and gilded materials, ground layer, textile support and binder used for the cartonnage. Aspergillus niger (24.8%), Penicillium chrysogenum (21.5%) and a novel cartonnage‐biodegrading bacterium, Bacillus sonorensis (23.7%), were the most abundant microbes growing over the cartonnage surface. In addition, Aspergillus tamari (15.4%), A. fumigates (8.1%) and Fusarium solani (6.5%) were identified. The pigments comprised Egyptian blue (cuprorivaite), cinnabar (red), orpiment (yellow) and green pigment made from a mixture of cuprorivaite and orpiment. Gold leaf was used for the gilded layer, calcium carbonate and gypsum comprised the ground layer, gum arabic was the binding medium and the fibre base was a fine linen textile. Microbial colonization tests were performed on aged cartonnage replica samples made from linen and pigments of similar composition to ancient pigments found in the cartonnage. Each sample was inoculated separately with A. niger, P. chrysogenum and B. sonorensis. Yellow orpiment samples were the exception, as no colour change was detected after colonization by the examined micro‐organisms.  相似文献   
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The discovery of Kef en-Naga site, an open-air human occupation in northeastern Algeria, was favored by a sandstone quarrying where work truncated much of the archaeological sequence on its cross-section. A multidisciplinary rescue excavation conducted on this site provided, for the first time in the region, the evidence of superimposition of two stratigraphic levels (lower and upper) of sandy clay deposits formed in humid paleoenvironmental conditions. Besides, XRD analysis show that a large amount of hematite (Fe2O3) is localized at the lower level of the stratigraphic section, where iron is found in oxide form due to the moisture. As for rock magnetic property characterization analysis, the various magnetic parameters have strong values in the upper level, and the grains are small-sized. However, various magnetic parameters are lower at the lower level and the magnetic grain concentration is reduced. Although the site is lacking faunal and carpological remains, thereby depriving us of reliable dates, the two stratigraphic levels are correlated to the Holocene according to archaeological and paleoenvironmental considerations. The lower level likely corresponding to an early Epipaleolithic culture marked by the production of microliths using a microburin blow technique, while the upper level is related to a subsequent Epipaleolithic phase, characterized by the disappearance of microburin blow technique, the dominance of an industry on flakes and the existence of pressure debitage.  相似文献   
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It is well known that the soil-structure interaction (SSI) changes the dynamic response of a structure supported on flexible soil. The analysis of optimally controlled SSI systems has certain difficulties due to the nature of the SSI and the optimal control problem. In this paper, a two-step iteration-based numerical algorithm is proposed to handle optimally controlled SSI systems under earthquakes. First, the optimal control forces are obtained by using a fixed-base system. Then, the optimal control forces are converted to the frequency domain by the Fourier transform technique to be used in the equations of the SSI system. The lateral displacement and the rocking of the foundation are obtained from the equations of the SSI system containing the optimal control forces in the frequency domain. The lateral displacement and rocking of the foundation are then converted to the time domain by the inverse Fourier transform technique, and the lateral accelerations and the rocking accelerations of the foundation are obtained by the forward finite difference method. During the second step, the optimal control forces are calculated again by using the lateral acceleration and the rocking acceleration of the foundation along with the earthquake ground motion. Using the method explained above, the optimal control forces obtained in the time domain are used in the equations of the soil-structure system from which the behavior of foundation and structure is obtained. In the final section of the paper, a numerical study is conducted for a controlled structure supported on flexible soil.  相似文献   
109.
The unexpected damages in structures during severe earthquakes have been reported frequently so far. In this study, the damage-based inelastic behavior of special moment resisting frame (SMRF) structures designed according to the new versions of general earthquake loading codes (International building code [IBC] 2012 & American Society of Civil Engineers [ASCE] 7-2010) and seismic design references (National Earthquake Hazards Reduction Program [NEHRP] 2009 & Federal Emergency Management Agency [FEMA] P-750) has been investigated. The final results presented based on distinctive shear and flexural failure modes show that a non-uniform distribution of severe damage in structural height occurs during design level seismic excitations. Also it is observed that the shear and flexural damages are more critical in short and tall MRF structures, respectively.  相似文献   
110.
Roger Keil  Harris Ali 《对极》2007,39(5):846-873
Abstract: Based on a case study of the 2003 severe acute respiratory syndrome (SARS) outbreak in Toronto, Canada, this article suggests that we may have to rethink our common perception of what urban governance entails. Rather than operating solely in the conceptual proximity of social cohesion and economic competitiveness, urban governance may soon prove to be more centrally concerned with questions of widespread disease, life and death and the construction of new internal boundaries and regulations just at the time that globalization seems to suggest the breakdown of some traditional scalar incisions such as national boundaries in a post‐Westphalian environment. We argue that urban governance must face the new (or reemerging) challenge of dealing with infectious disease in the context of the “new normal” and that global health governance may be better off by taking the possibilities that rest in metropolitan governance more seriously.  相似文献   
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