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51.
The seismic assessment of special bridges, even under the hypothesis of full knowledge of site conditions, structural characteristics, and seismic activity at their location, is not an easy and straightforward task due to the complexities and uncertainties related to the finite-element modeling approaches, structural loading scenarios, and seismic analysis methodologies. In this article, a series of nonlinear static and dynamic finite-element analyses on the Mogollon Rim Viaduct are performed with consideration of both uniform and conditionally simulated non-uniform seismic motions. The failure modes of the bridge using different numerical modeling approaches are discussed, and the degree of sensitivity of its response to the different seismic assessment strategies is evaluated. The effect of the multi-component, multi-support and multi-directional excitations of ground motions on the design and response are studied, and the pros and cons of the commonly used structural analysis methodologies of bridges are also addressed. The numerical results of the present study provide a deeper insight into the nonlinear behavior of curved reinforced-concrete bridges, and suggest practice-oriented approaches for their seismic assessment.  相似文献   
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53.
The townscape of “old” Lerwick reflects its traditional focus on the sea for its economic base. The major elements in this cohesive visual character are the closely clustered houses in the steep hillside district of the Lanes, the narrow, winding principal commercial street, and the lodberries projecting out into the harbour. The latter were constructed to meet the needs of the prosperous expanding trade period of the latter half of the 18th century and first half of the 19th century. Harbour improvements in the final quarter‐century of the 1800s ended their commercial usefulness. After a century of declining use and of neglect they are being restored as part of the renewal of “old town” Lerwick.  相似文献   
54.
[I] want to single out one phenomenon that could be called the ‘politics of sources’. It points to the extent to which the histories that both scientists and historians can write are artifacts of the available sources. The Rockefeller Foundation not only opened its archives very early on for historical work but also invested a lot in making the archives readily available for historical exploration. During the 1980s, many young historians took advantage of this opportunity. Thus, in a relatively early phase of the professional historiography of molecular biology, one could have gained the impression that the development of the new biology as a whole was a bio-politically directed enterprise of the Rockefeller Foundation sustained by the vision that social processes could ultimately be controlled by biological processes.  相似文献   
55.

This article explains the often neglected history of the Spanish telephone sector. Its main purpose is to examine the factors that determined the technological choices that were made in this sector, and to describe and analyze the growth of telephone networks in Spain and the rest of Europe between 1876 and 1924, a period marked by the internationalization of technology. It concludes that a complex range of factors, varying in their specific importance over the period, determined the pattern of technological diffusion in this sector. In the period dominated by Bell's patents, the sector was characterized by a high degree of technological homogeneity. However, once the licenses on these patents expired, a greater variety of technological devices were adopted in the sector, although this variety was limited by the control that the larger firms wielded over the market and policies of international cooperation. Spain, unable to keep pace with technological developments elsewhere in Europe, failed to establish its own national industry of telephone materials and equipment.  相似文献   
56.
By focusing on the key book‐length studies of the Apollo program that landed American astronauts on the Moon in the 1960s and 1970s, this essay seeks to evaluate the historiography about Apollo in the first decade of the twenty‐first century, dividing the subject into five major areas. The first area is the foreign policy and public policy antecedents of Apollo and its immediate ramifications; some of these efforts have yielded significant studies. The second area involves the evolution of space hardware, in many instances these are overwhelmingly detailed studies of rockets and other space flight technologies. Third, there is a great fascination with the astronauts and their actual flights, and a rich tradition of memoir and narrative exists in this arena. The fourth area receiving attention from historians of Apollo and the lunar voyages emphasizes the history of science, in which much of the focus is on the scientists, scientific findings from the voyages of discovery, and the use of this evidence in developing larger theories about the origin and evolution of the solar system. Finally, and increasingly so in the last 20 years, the Apollo story has been recontextualized through social and cultural investigations of its meaning in modern America. Assessing the five major areas enumerated above, this essay also offers some possibly fruitful avenues of future research.  相似文献   
57.
The paper explores processes of transnational network building in Europe in the 19th and 20th centuries. The first section reviews several relevant literatures. It concludes that historiographies of Europe often recognize the pivotal importance of transnational network building, but fail to analyse network developments as well as their entanglement with wider historical processes. Specialized infrastructure studies exist in economic and technological history, but have a distinct (sub)national focus. The networking of Europe has not been investigated. The second section presents a preliminary narrative of transnational network building in the 19th and 20th century. It highlights the relationship between network building and political events in different eras, as well as different types of ambiguities or tensions. The conclusion suggests a number of topics for further research.  相似文献   
58.
Benedetto Croce was the author of the most important and original theory of history in the 20th century. His theory was that of ‘absolute historicism’, and this necessarily entailed an acute critique of inherited ideas about the Enlightenment. This article studies both Croce's theoretical analysis of Enlightenment and his historical analysis of the Neapolitan Enlightenment. Croce's interest in the Enlightenment had political as well as philosophical roots. All over Europe in the 1920s and 1930s historical and theoretical research was occurring into in the Age of Enlightenment. The broad goal of such research was to bring forth a new concept of reason, which would have purchase in the contemporary debate about rationalism and irrationalism. This debate, which flourished in the era of totalitarian regimes, raised a series of further questions: What was culture? What was the task of culture in the fight against political irrationalism? What was the relationship between culture and the growth of public opinion? With respect to the latter relationship an important role was played by intellectuals, as evinced by the works of Benda, Max Weber and Croce himself. The genealogy of the modern intelligentsia led again to Enlightenment. In the third part of the article Croce's position on this issue is discussed in the light of his historical researches on Enlightenment by reference to his correspondence with two young historians, Delio Cantimori and Franco Venturi.  相似文献   
59.
Contributing to the surging interest in rhetorical uses of anecdotal narratives in ancient China, the present article investigates sources about a purported follower of Confucius going by the name of Yan Zhuoju, or variants thereof. The main advantage of focusing on such an obscure figure is that extant sources can be exhaustively analysed – an approach intractable for more fully documented personalities – in order to gauge the mechanisms which created the textual record historians utilise to reconstruct events of the ancient past. The article demonstrates how the same figure can be appropriated across different discourses, to wit, in attacks on Confucius's alleged improprieties; in attempts to counter such attacks; and in arguments for the increasingly meritocratic social order of the Warring States period. Rarely adding up to a complete story, such appropriations are constituted by fragmentary narratives, summary statements, and intertextual references.  相似文献   
60.
In the early modern period, the European concept of “nobility” was rarely used to describe the upper classes of the societies born in the British or in the French Americas. The presence of French nobles in New France or in the French West Indies and the emergence of the native gentry in parts of the British Empire have been much studied. But the social impact of elites has not been fully recognized by Atlantic historians—due, perhaps, to a bias towards “authentically” New World systems of social recognition based upon wealth, emphasizing supposedly greater possibilities of social mobility. This paper takes a comparative perspective to the social meanings of being a noble or being a gentleman in both empires. It concludes that there were few substantive differences between French nobles living in the metropolis and in the colonies because legal definitions of the French noblesse were strictly determined by the Crown. The essence of the French nobility was, in theory, the same in Versailles, in a remote rural parish of France or in Quebec. The story was very different for British colonial gentlemen who encountered countless difficulties to be socially accepted by their metropolitan counterparts. The paper explores the consequences of the chasm between British metropolitan and colonial upper classes and assesses solutions taken by colonial gentlemen to be fully integrated in the gentry of Great Britain.  相似文献   
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