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This article aims at presenting and discussing the strategies for updating the finite element numerical modeling of stone masonry arch bridges using operational modal analysis. The study comprehended three bridges: two old ones, the St. Lázaro and the Lagoncinha bridges, and a recently constructed bridge in Vila Fria, Portugal. Updating of the bridge models is performed by comparing the numerical and experimental modal parameters. Three-dimensional detailed numerical models are used to perform modal analysis of the bridges. Experimental modal identification of the bridges is based on the measurement of their acceleration responses during normal operation. The assigned material properties are also based on available results obtained from in situ and laboratory tests and on the results of visual inspection and historical research carried out for both old bridges.  相似文献   
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Abstract

A consistent access to food is paramount for humans at individual and group level. Besides providing the basic nutritional needs, access to food defines social structures and has stimulated innovation in food procurement, processing and storage. We focus on the social aspects of food storage, namely the role of cooperation for the emergence and maintenance of common stocks. Cooperative food stocks are examined here as a type of common-pool resource, where appropriators must cooperate to avoid shortage (i.e. the tragedy of commons). ‘Food for all’ is an agent-based model in which agents face the social dilemma of whether or not to store in a cooperative stock, adapting their strategies through a simple reinforcement learning mechanism. The model provides insights on the evolution of cooperation in terms of storage efficiency and considering the presence of social norms that regulate reciprocity. For cooperative food storage to emerge and be maintained, a significant dependency on the stored food and some degree of external pressure are needed. In fact, cooperative food storage emerges as the best performing strategy when facing environmental stress. Likewise, an intermediate control over reciprocity favours cooperation for food storage, suggesting that concepts of closed reciprocity are precursors to cooperative stocks, while excess control over reciprocity is detrimental for such institution.  相似文献   
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In this article, I explore the parallel responses of two groups of colonial subjects who were confronted with the institutional changes that occurred in the context of Enlightenment ideas in eighteenth-century Mexico: creole clerics headed by the Jesuit Francisco Javier Clavijero; and native religious men who petitioned to colonial authorities and the Crown for additional spaces for the education of indigenous men. I explore some of the interactions between creole clerics—often referred to as creole patriots—and native elites in the schools of central Mexico, and efforts by indigenous noble men to broaden the opportunities for natives to join the ranks of the Church and to receive a higher education. To this end, I build on the scholarship that has made evident how the hegemonic program of Bourbon reforms, which was inspired by the Enlightenment, was not a top-down plan implemented successfully and equally across the continent but rather a series of contested interpretations. This article contributes to the recent shift in the scholarship on the Enlightenment that acknowledges cross-cultural global exchanges by arguing that certain groups of natives in central Mexico, and a particular group of American-born clerics, participated actively in building a pragmatic version of the Enlightenment that responded to their local realities and contributed to a globalized understanding of enlightened ideas.  相似文献   
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An essential element usually passes unnoticed in recent discussion about how history as an academic discipline is supposed to be relevant for the shaping of our public life. It is the concept of history itself (history as both the course of events and historical writing) that underlies the whole discussion, which also configures the two currently most influential and fashionable efforts to reinstate the public relevance of history: The History Manifesto, co-authored by Jo Guldi and David Armitage, and Hayden White's The Practical Past. In advising to turn to the past in order to shape the present and the future, both books rely on the familiar developmental view that characterised nineteenth-century thinking in general, and on which the discipline of history became institutionalised in particular. The author's main contention in this essay is that turning to this notion of history is not the solution for the problem of the supposed public irrelevance of professional historical studies, but the problem itself. The developmental view, based on a presumption of a deeper continuity provided by the subject of the historical process that retains its self-identity amid all changes, certainly suited the discipline of history when it was engaged in the project of nation-building. However, it hardly fits our present concerns. These concerns, like the Anthropocene, take the shape of unprecedented change, and what they challenge is precisely the deeper continuity of the developmental view. The discipline of history can regain public relevance only insofar as it proves to be able to exhibit a thinking of its own specificity which can nevertheless explain such unprecedented changes. What such historical thinking could provide is what the developmental view can no longer: the possibility to act upon a story that we can believe.  相似文献   
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Territorial capital has gained considerable attention in the past few years. The aim with this work is to throw light on some underlying aspects of territorial capital research. The study focuses on the theoretical and empirical issues of territorial capital and highlights some critical remarks related to the topic. On the one hand, the focus of the study is on the comparison of concepts and approaches in connection with territorial capital; then an in-depth look is taken at “capital frameworks” related to the research field. On the other hand, a comprehensive overview is presented of empirical investigations by comparing the applied methods, dimensions and variables of territorial capital. An argument is also made for a critical assessment concerning the topic with regard to the sense and function of territorial capital in regional economics and local economic development and highlights some further dilemmas concerning the “properties of capital” and “territorial capital paradigm”. Finally, some suggestions are provided for the future of territorial capital analysis. The main result of the study is an own belief in the concept of territorial capital.  相似文献   
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The objective of this paper is to assess an approach to statistical modeling of point referenced establishment data that permit inclusion of “environmental” or establishment‐specific covariates and specific forms of interestablishment interaction. Gibbs models are used to decompose the conditional intensity of the spatial point process into trend and interaction components. The trend is composed of access measures (primarily different classes of roads) and three different interaction processes are tested: Geyer, area interaction, and Strauss hard core. While the models used have proved to be useful in ecology, we are unaware of any applications to establishment or firm data. In empirical application, the models yield intuitively appealing results for the trend component, and the ability to specify the interaction component gives deeper insights into interestablishment spatial dynamics than any previously published methods.  相似文献   
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