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A simplified model useful for assessing economic losses due to moderate seismicity events in urban areas has been developed by studying the behavior of buildings before yielding their structural system, allowing for nonuniform stiffness along their height. In particular, buildings are modeled as cantilever shear beams with uniform mass and parabolic reduction of lateral stiffness. This particular stiffness distribution is relevant, as it could be expected to occur in buildings where earthquake action is a critical structural design criterion. The equation of motion governing the dynamic behavior of the proposed model is solved analytically, finding mode shapes in terms of first and second zero-order Legendre functions. The solution is verified by comparing it with results obtained from fine mesh finite element models. The effect of reducing the lateral stiffness is then studied in the first five modes of vibration. Results include modal periods, mode shapes, modal participation factors, and derivatives of mode shapes. In general, it is found that effects of reduction of lateral stiffness in mode shapes are moderate when the lateral stiffness in the free end is smaller than about seventy percent of the lateral stiffness at the fixed end, but become significant for larger reductions. Effects are particularly important for the derivative of the mode shapes, which could play a significant role in estimating interstory drift demands in buildings. Model usefulness is showcased by analyzing a test case where both acceleration and drift demands are assessed by considering uniform beams and beams with parabolic stiffness variation, finding notable improvements by considering the latter.  相似文献   
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Kelly, R.S. & Nel, A., October 2017. Revision of the damsel-dragonfly family Campterophlebiidae (Odonata) from the Early Jurassic of England reveals a new genus and species. Alcheringa 42, 87–93. ISSN 0311-5518.

Historical fossil insect collections from England were re-examined and the taxa revised. Lateophlebia gen. nov. is erected for Liassophlebia anglicanopsis (Zeuner) in Campterophlebiidae. Petrophlebia anglicana Tillyard is confirmed in this family and Archithemis liassina (Strickland) is transferred to this family. Lastly, Archithemis brodiei (Geinitz), Archithemis Handlirsch, and Architemistidae Tillyard (reduced to this sole species) are transferred to the Heterophlebioidea.

Richard Kelly [], School of Earth Sciences, University of Bristol, Life Sciences Building, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK; Department of Natural Sciences, National Museum of Scotland, Chambers Street, Edinburgh, EH1 1JF, UK. André Nel [], Institut de Systématique, Évolution, Biodiversité, ISYEB—UMR 7205CNRS, MNHN, UPMC, EPHE, Muséum national d’Histoire naturelle, Sorbonne Universités, 57 rue Cuvier, CP 50, Entomologie, F-75005, Paris, France.  相似文献   

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Teaching of critical spatial thinking in higher education empowers graduates to effectively engage with spatial data. Geographic information systems (GIS) and science are taught to undergraduates across many disciplines; we evaluate how this contributes to critical spatial thinking. The discipline of GIS covers the whole process of spatial decision-making, but GIS modules often ignore the context setting of spatial problems, and just cover the technical aspects of how to use GIS software. We outline how some existing GIS practicals could be improved to focus on the development of critical spatial thinking skills, competences and abilities that are valuable to graduates.  相似文献   
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This paper explores the effectiveness of policies ‘in’ attracting the foreign research and development (R&D) of multinational enterprises (MNEs) to specific countries in Europe. We develop a macroeconomic investigation covering 29 European countries during the period between 1990 and 2012 in order to address: (a) whether the provision of direct financial support for business R&D is effective for the attraction of foreign R&D; (b) whether direct support is more effective than indirect support for this purpose and (c) whether the link between direct financial support for business R&D and the foreign R&D of MNEs is conditioned by the context within which the support is provided. The results of the analysis show that, first, the provision of direct financial support is generally effective for the attraction of foreign R&D by MNEs. Second, direct support for business R&D is more effective for this purpose than indirect support. Third, the provision of direct financial support for business R&D yields greater returns in contexts that are more socio-economically suitable for knowledge-intensive, innovative activity.  相似文献   
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This article analyses European ‘youth riots’ as a social phenomenon after World War II. It also uses a specific riot – the 1948 Stockholm Easter Riots – in order to discuss the limits and potential of some theoretical assumptions underlying the field of historical contentious politics studies, primarily ‘contentious politics’ and ‘claims’. Using police reports and newspapers, the article shows that the riots were part of a European repertoire of post-war ‘youth riots’, but that they also bear similarities to an older popular repertoire of contention in Sweden. However, the riots do not really fit into the concept of ‘contentious politics’, as this concept is built on ‘claim-making’ as a key aspect and the participants did not make explicit claims. This leads to the conclusion that other theoretical tools, inspired by the concept of ‘moral economy’, are better suited for understanding the motivations of the rioters, whose actions are interpreted as a way of defending a perceived moral right of access to the urban public space.  相似文献   
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This article presents the life stories of six indigenous women from the Amazonian region, who coordinate local women processes through indigenous organizations and networks. Since the political and legal visibility of violence against indigenous women in Colombia is weak and limited, we aim to analyze their experiences from an intersectional perspective. For this purpose, we employed multiple methodologies, including body mapping and social cartography. Thus, by reconstructing their experiences and attempts to make visible violence against them, we could perceive some of its multiple modalities, which are quickly captured by the great category.  相似文献   
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During every war between Denmark and Sweden from at least 1505 to 1676 popular peace treaties were concluded by common men on both sides of the national border. These treaties were negotiated in contrast to the aggressive policy of the political leaders and to the nationalistic discourse of the elite. The aim of this article is to use archaeology to give an economic, social, and mental background to these treaties, and to the regional identity across the border that they presuppose. Above all a specific building tradition seems to have given the peasants a mental affinity across the border.  相似文献   
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Comparative policy studies face a number of methodological challenges where conceptualization of the object of comparison—policy output—is the most fundamental. On the basis of three common approaches of the study of policy output, we reconsider this widely applied concept and propose a refined measure as a function of both density (number of policy instruments) and intensity (content of policy instruments). We theoretically derive six policy‐intensity measures (objectives, scope, integration, budget, implementation, and monitoring), which are used for weighting national policy instruments on an Index of Climate Policy Activity. The article presents an empirical application of this measurement approach. Focusing on national climate policy instruments in the energy production sector in Austria, Germany, and the United Kingdom, we investigate changes in the countries' policy portfolios from 1998 to 2010. The article demonstrates that our Index of Climate Policy Activity provides a reliable and valid measurement for national policy output that can be applied for comparative analyses of policy output.  相似文献   
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