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21.
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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According to the Act of 1996 on nature protection, mounds (kurgans) are natural monuments protected nationally in Hungary. According to the law, all kurgans in Hungary were to be surveyed by 2002, and 1692 were included in the cadastre. Fewer than half of the kurgans remained intact due to numerous anthropogenic impacts. A high number of disturbing artificial buildings together with soil erosion, soil removal, and afforestation have significantly reduced the landscape value of kurgans. In 2002, 51.5% of the surveyed kurgans still represented some kind of a value and thus their protection became one of the most urgent tasks of nature conservation and archaeology. According to a Hungarian ministerial decree, established on the basis of an EU Council decree, the area of kurgans under cultivation must be removed from cultivation. By 2015, in the area of 90% of the kurgans under cultivation this land use, which caused significant erosion, was terminated.  相似文献   
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ABSTRACT

This article examines cultural policy strategies supporting urban regeneration, focusing on its particular characteristics in the Ibero-American context. We start by developing a systematic contrast between the different circumstances that have led to the emergence of these strategies in the Ibero-American sphere and in other parts of the world. Our examination of the Ibero-American regenerative experience also includes a consideration of the paradigmatic cases that arose initially in the Iberian Peninsula and the typological analysis of subsequent Latin American experiences. The consideration of all these different elements ends up providing a global vision of the specificity of the phenomenon in its Ibero-American context.  相似文献   
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In the area of cultural heritage, tourists’ experiences emphasise not only the moment and its personal nature but also socio-cultural traits. These experiences when expressed (social communications) are an important gateway to knowledge about tourists’ sense-making processes. This paper reports on the mediation between tourists and heritage sites via comments on a digital platform (TripAdvisor) about two Spanish tourist destinations with opposing characteristics and four heritage sites, which are analysed. The methodology used seeks to transcend the individual and anecdotal aspects of tourists’ comments. Indeed, the results obtained show the relevance of the humanisation and the discursive weight of heritage contexts in emotional/personal stories. Tendencies observed in non-regulated contexts confirm the role of a complex negotiation at cultural heritage sites and highlight the need to explore possible exchanges of sense in tourists’ encounters with such sites.  相似文献   
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The restoration of paintings on elements in cultural heritage buildings (fundamentally, churches) involves two structural problems: capturing the geometry of the construction element and its development. In many cases, the geometries are regular (e.g., cylinders, spheres, elliptical domes). However, there are cases in which the elements cannot be adapted to any known geometry, much less one that can be mathematically developed. The development of surfaces becomes essential for the restoration of paintings over “flat elements” (over which work is performed on the ground) that are subsequently transferred to the real surface (ceilings). The mathematical transformations that allow regular geometries to be developed are widely known (cartographic projections). However, when the geometry is irregular, there is no development. This study presents a new methodology based on differential rectification and its application for the development of oculi in the Los Santos Juanes Church (Valencia), whose geometry is completely irregular both in shape and as a result of construction defects (and damage caused by fire). The present study focuses on the restoration of paintings damaged by fire.  相似文献   
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A vibrant artisanal fishery of the brackish water marsh clam (Polymesoda acuta) is located in the lower Río Tempisque, Costa Rica. Fishermen harvest clams from shoals according to tidal and lunar cycles. They take most clams directly to riverside processing stations to be cooked and sold as salted meat, although some cooked clams are dried, and others sold live. Processing activities result in the formation of shellmounds that share significant similarities and some differences with ancient marsh clam shellmounds of coastal Chiapas, Mexico. In this study, procurement and processing activities are described and quantified, revealing the substantial amount of labor and skill involved in the modern fishery. Implications for archaeological preservation and predictions from optimal foraging theory are evaluated.  相似文献   
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ABSTRACT

The “Quartel das Esquadras” is an 18th century infantry barrack located within the limits of the bulwarked fortress of Almeida, in Portugal. An ongoing adaptive reuse project of the building aims to recover its full capacity and also its importance, by implementing a variety of new uses. The architectural intervention results in the need of the structure to withstand new and diverse imposed loads. As the current configuration of the structure will be altered, the main objective of this article is to evaluate the suitability of some of the proposed structural interventions. The current condition has been characterized following a multidisciplinary approach comprising historical research, visual inspection, non-destructive testing, and structural analysis to identify the possible sources of major structural problems. A portion of the building particularly affected by the alterations has been selected to carry out structural analysis. A comparative safety assessment of the selected area in both current and altered condition has been done through finite element modelling and nonlinear static analysis, resulting in an identification of the weaker points against the new implemented loads and alterations. Finally, proposals for the implementation of the studied intervention, as well as recommendations for future research and analyses, have been given.  相似文献   
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This paper narrates Puerto Rico's fiscal and financial crisis through a reading of San Juan's urban landscape. We underscore the role of capital in the city, primarily embodied by the local capitalist class (the Criollo bloc) and foreign capitalists. Historically excluded from the manufacturing sector (dominated by US capitalists), the Criollo bloc accumulates its wealth by concentrating financial assets in the city. In times of crisis, the Criollo bloc resorts to the acquisition of new assets and asset exchange with foreign capitalists to remain solvent and provide short‐term solutions to the state's fiscal and financial limits. The survival of the local capitalist class, we demonstrate, is dependent on asset stripping. Drawing on Clyde Woods, we document how asset stripping unevenly redistributes wealth and risks along class and racial lines within a colonial economy. The finance capital/asset stripping basis of San Juan's economy renders it an extremely fragile city, we contend.  相似文献   
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