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991.
992.
Past earthquakes have demonstrated that historical vaulted adobe buildings are highly vulnerable to seismic actions. Hence, it is crucial for such building typologies to be evaluated in terms of seismic capacity. To this end, this article deals with the seismic performance of historical vaulted adobe houses from the city of Yazd, Iran as one of the seismically active areas of the world and possessing a very rich adobe heritage. Thus, and based on a detailed geometrical survey, a representative sample of adobe houses from Yazd was studied using a simplified in-plane analysis based on three geometric indexes. Concerning the out-of-plane behavior, a deeper assessment was conducted by performing a numerical study, where the main influential parameters on the seismic behavior of vaulted adobe buildings were considered. The numerical analyses were carried out by adopting the limit analysis theory implemented in the Block2D software. The results obtained indicate the safe in-plane behavior of most of the houses and the safe out-of-plane response of the sample under gravitational loads. However, the sample out-of-plane safety under earthquake-induced loads seems to be a matter of concern.  相似文献   
993.
Ground-borne vibrations induced by mine blasting are typically of low amplitudes, which are not considered a major concern for modern engineered structures. However, historic structures are often considered more vulnerable due to inadequate knowledge regarding the state of construction materials and structural response. Specifically, the construction materials used might be fragile or have deteriorated to a stage that could be vulnerable to such vibrations. Simplistic rule based on peak ground motion parameter has been adopted worldwide for safety assessment, while the frequency characteristics of vibrations are not taken into account. Further, there is very limited study on response of heritage structures to near-field blasting. This article presents a practical structural vulnerability assessment method for mine blast-induced vibrations. In particular, a design response spectrum model is proposed based on close range measurements of nearby mine blasting, which is compared with an existing design spectrum model for far-field mine blasts and a typical design spectrum model for earthquake actions. The method is illustrated through a case study of heritage masonry buildings in Australia. The unique blast data presented and the generalized methodology would be useful to both structural engineers and blast engineers in considering potential effects of blasting on heritage structures.  相似文献   
994.
ABSTRACT

Building survey is an essential data-collection procedure to feed large-scale seismic vulnerability assessment. The available strategies usually consider survey forms to gather information about the urban buildings. The application of the available survey forms poses important challenges for the case of the heterogeneous urban centers including different structural typologies. This work proposes four specific survey forms for traditional structural typologies constructed with masonry, reinforced concrete, mixed steel-reinforced concrete, and timber. The proposed forms request essential information on the parameters necessary for seismic vulnerability assessment, by evaluating the lateral-load resistant system, regularity, condition of conservation, and existing damages. The survey forms were applied to the study of 111 buildings of the historical center of Valparaíso, Chile. The proposed methodology was complemented with the use of Geographic Information Systems to obtain a complete database with the structural characterization of the most representative typologies for future works of large-scale seismic vulnerability assessment.  相似文献   
995.
Practically all archeological assemblages are palimpsests. In spite of the high temporal resolution of Abric Romaní site, level O, dated to around 55 ka, is not an exception. This paper focuses on a zooarcheological and taphonomic analysis of this level, paying special attention to spatial and temporal approaches. The main goal is to unravel the palimpsest at the finest possible level by using different methods and techniques, such as archeostratigraphy, anatomical and taxonomical identification, taphonomic analysis, faunal refits and tooth wear analysis. The results obtained are compared to ethnoarcheological data so as to interpret site structure. In addition, activities carried out over different time spans (from individual episodes to long-term behaviors) are detected, and their spatial extent is explored, allowing to do inferences on settlement dynamics. This leads us to discuss the temporal and spatial scales over which Neanderthals carried out different activities within the site, and how they can be studied through the archeological record.  相似文献   
996.
The presence of processed birds in the archeological faunal record is considered key to assessing human dietary evolution. Taphonomic studies on birds from sites older than Marine Isotope Stage (MIS) 2 have become relevant in the last few years, leading to the proposal of more complex scenarios of human subsistence. Several works have demonstrated direct evidence of bird consumption by Homo prior to anatomically modern humans in Europe; however, others support the hypothesis of non-anthropogenic bird accumulations. This has led to the necessity of determining what elements or factors cause the human exploitation of birds in some archeological sites before the end of the Pleistocene. The Grotte des Barasses II site is located within this framework. Short-term human occupations have been attested by the presence of lithic tools and processed macrofaunal remains. Additionally, a small assemblage of bird bones has also been recovered. Here, we present a detailed taphonomic study with the aim of exploring possible relationships between these avian taxa and human occupations. Despite the fact that Neanderthals inhabited the cave, avian specimens show damage pointing to different causative agents. Direct evidence (digestion, gnawing) indicates that mammalian carnivores and nocturnal raptors were mainly involved in the accumulation of bird bones. We propose some factors that might determine whether or not small game was exploited in this specific locality and emphasize the importance of such analytical approaches in the general interpretations of the Pleistocene sites.  相似文献   
997.
The anthracological study of Paredón Lanfré (Patagonia, Argentina) highlights the presence of radial cracks with a marked difference between the percentage of affected coniferous charcoal (Fitzroya cupressoides and Austrocedrus chilensis) compared to the angiosperms (e.g., Nothofagus antarctica and Nothofagus dombeyi). The aim of this work was to obtain experimental comparison data from two Patagonian conifers to understand the prehistoric combustion behavior of the region. These results showed a discrepancy between the average of shrinkage cracks made with green wood fires and those with dry wood fires. The study of the caliber of charcoal recovered from Paredón Lanfré showed significant differences between the samples of F. cupressoides and A. chilensis. The calculation of correlation between size and shrinkage cracks suggests for both species that the size is not related to the number of registered shrinkage cracks in charcoal studied. Therefore, the gauge would not be a variable which could influence the presence of shrinkage cracks in the charcoal. Consequently, the difference of average shrinkage cracks between the two specimens may result from another variable that remains to be identified.  相似文献   
998.
正ISBN:978-1-934536-68-1,pp.136,31 color,9 b/w illus,$59.95.Since"The Belt and Road Initiative"reviving the ancient trade land and maritime trade routes was proposed by the Chinese state at the end of 2013,the routes linking East and West by land and sea,whereby silk,spice,and glass were transported by ship or camel,are frequently mentioned.From East Asia to Europe,it garners increasing attention from institutes,think-tanks,and forums  相似文献   
999.
Since the Cold War, South-East Asia has been marked by a period of relative calm and stability. Yet this peace belies ongoing tensions, mistrust and stress in the Association of Southeast Asian Nations (ASEAN) and among its member states. Within the scholarship on ASEAN, not enough attention is devoted to these underlying currents. How and in what way do tensions stress the ASEAN norms? What are some of the coping mechanisms adopted by ASEAN and its member states? Engaging with the scholarship on norms, the author contends that changes wrought in this relationship are both extra- and intra-mural. These have accelerated as contentious issues—particularly the South China Sea disputes—gain more visibility. The author argues that ASEAN is put under pressure, firstly, through a more muscular Chinese foreign policy that disrupts but does not yet break the fundamental norms of ASEAN and, secondly, through internal contestation over ASEAN norms that challenges the meaning of these norms. Essentially, the article gives an account of how internal and external pressures are burdening ASEAN norms but yet remain durable because of resistance against duress by the bloc and member states. This is done through an examination of instances where the established order and practices in the region were disturbed, and the response to this disturbance.  相似文献   
1000.
Erica Benner and Leo Strauss have recently challenged the reigning consensus that, having concentrated on politics, Machiavelli was not a philosopher. Readers did not always consider Machiavelli's work to be unphilosophical; and whether a commentator considers Machiavelli to be a “philosopher” depends on his or her understanding of what a philosopher is. Neither Benner nor Strauss takes the activities and studies of professors of philosophy in universities today to be definitive. Instead, they look to an older tradition both describe as “Socratic.” Benner rests her argument primarily on Machiavelli's references to Xenophon, Plato, and Plutarch. Unfortunately, Machiavelli's references to the works of Xenophon and Plato do not include those that feature Socrates. Strauss points out the similarities between Socrates and Machiavelli's emphasis on the political and their appeal to the young, but he concludes that, although Machiavelli is a “political philosopher,” his use of philosophy to serve the desires of the demos means that he is not a “Socratic.”  相似文献   
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