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A reliability-based methodology to estimate strength amplification factors for structures with asymmetric yielding is proposed. The approach is based on structural demand hazard analyses. Nonlinear time-history analyses of tridimensional simplified systems are carried out. The effects of two orthogonal components of the seismic ground motions and soil-structure interaction, are considered. Results show that the expected ductility demand of systems with asymmetric yielding may be much higher than those of symmetric systems. A simplified mathematical expression (which is function of the ratio between the fundamental vibration period of the system and that of the soil, ductility demand, and level of asymmetric yielding) is proposed to estimate the amplification factors. The expression is applied successfully to a 9-story reinforced concrete building exhibiting asymmetric yielding produced by tilting.  相似文献   
63.
A group of Euganean trachytic grinding stones from Slovenia and the available data about the same type of artefacts in the whole Caput Adriae are presented. The occurrence of Iron Age saddle querns in Karst and Istria is confirmed, but our study suggests a likely provenance from Mts Cero/Murale instead of Mts Altore/Rocca Pendice, as previously suggested. Este, an important Venetic centre, is just south of Mts Cero/Murale, suggesting its central role in the production and distribution of saddle querns. During the Roman period Euganean trachytes are still used for rotary millstones, but new quarries (Mt Rosso), relatively close to ancient Padua, are exploited. Such shift in the position of millstone quarries most probably reflects the changed geopolitical framework.  相似文献   
64.
Camillo Negro, Professor in Neurology at the University of Torino, was a pioneer of scientific film. From 1906 to 1908, with the help of his assistant Giuseppe Roasenda and in collaboration with Roberto Omegna, one of the most experienced cinematographers in Italy, he filmed some of his patients for scientific and educational purposes. During the war years, he continued his scientific film project at the Military Hospital in Torino, filming shell-shocked soldiers. In autumn 2011, the Museo Nazionale del Cinema, in partnership with the Faculty of Neurosciences of the University of Torino, presented a new critical edition of the neuropathological films directed by Negro. The Museum’s collection also includes 16 mm footage probably filmed in 1930 by Doctor Fedele Negro, Camillo’s son. One of these films is devoted to celebrating the effects of the so-called “Bulgarian cure” on Parkinson’s disease.  相似文献   
65.
The experimental characterization of historical bell towers and wall belfries can provide important information for the calibration of numerical models as well as to implement proper restoration strategies. Within this framework, the presented study is concerned with the experimental dynamic assessment of an ancient belfry dating back to 1537. The structure is part of the “Santa Maria in Aracoeli Church” (Rome, Italy), an important heritage construction placed on the summit of the Capitoline Hill, close to the building that hosts the Major’s office. Several field tests have been conducted using accelerometers, and records obtained under different dynamic loading scenarios have been examined. Moreover, experimental accelerations have been elaborated to estimate the most important modal features of the structure and to validate a finite element model. Field tests have confirmed that severe vibrations are induced when the bells swing, and thus a slight reduction of the swing angle has been suggested in order to provide an immediate and inexpensive benefit to the structure. A new set of field tests demonstrates that the new swing angle is sufficient to reduce the induced vibrations while preserving the original sound.  相似文献   
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This paper reports the results of a long-term project on the stone axes from Caput Adriae. Available data show that jade axes originating in the western Alps reached the Neolithic groups of Friuli Venezia Giulia and coastal Istria as early as the second half of the 6th millennium BC, during the Danilo/Vla?ka culture. The exchange of this and other classes of lithic artefacts testifies that in this period this area was fully integrated into long-distance exchange systems that used mainly coastal routes. These systems would have continued in the 5th millennium BC, as indicated by a few oversized jade axe blades and other materials. Far from the coast, jade axes entered central Slovenia, probably reaching sites of the Sava Group of the Lengyel culture in the first half of the 5th millennium BC. In roughly the same period, shaft-hole axes made of Bohemian metabasites (BM) spread over central and southeastern Europe, crossed the Alps and reached Italy. According to different Neolithic traditions, during the 5th millennium BC Europe appears to be divided into a jade-using western area and a central-eastern BM-using one. During the 4th millennium BC, the exchange networks of Caput Adriae are increasingly influenced by the eastern Alpine and Balkan world, where the raw material sources of the main groups of shaft-hole axes are located. The association of the rocks used for axe production and copper ore suggests that the changes in raw material exploitation strategies during the Copper Age were probably related to the development of the first metallurgy.  相似文献   
68.
Pigments appearing on ninth–twelfth-century AD-carved stucco, wall painting, and terracotta friezes excavated at Nishapur in north-eastern Iran were investigated by optical reflectance spectroscopy, micro X-ray fluorescence spectrometry (μ-XRF), X-ray diffractometry (XRD), micro-Raman spectroscopy (μ-Raman), and scanning electron microscopy (SEM). Many of the pigments identified including vermilion, red lead, hematite, limonite, carbon black, atacamite, calcite, and gypsum have been identified in previous studies of pigments used in later Islamic periods. However, a series of unusual pigments such as wulfenite, pyromorphite, phoenicochroite, and jarosite were also found in the present study. The association of kaolinite and alunite with limonite and other Fe-bearing yellow pigments points to a local provenance for these pigments. In addition, the presence of orpiment in the vermilion may be indicative that the vermilion was artificially manufactured. These findings suggest that pigment use and manufacturing during the ninth to eleventh centuries in Nishapur was still in a trial-and-error stage and the palette known from the twelfth century onwards had not yet been systematized.  相似文献   
69.
This paper examines the geographical imaginations associated with aviation in fascist Italy, focusing on the representation of flight on the one hand, and on the other hand the role of propaganda flights organized by the regime in the 1930s. The representation and use of aviation in interwar Italy is explored in light of the concept of technological legitimation, based on an understanding of technological practice as a political and ideological instrument. Aviation, as one of the new subjects of artistic representations of the modern era, was grasped by avant-garde and modern movements in the early twentieth century. In turn, representations of aviation were used by Mussolini's regime, which considered it a key to national development and modernization, materially as well as in the representational sphere. Propaganda flights in 1930s Italy were organized by the Ministry of Aeronautics and local aero clubs, and were an expression of the politicized use of aviation, both in terms of representations of technology and the aviator, and the exploitation of flight's public potential for the construction of fascist spectacle.  相似文献   
70.
Federico Ferretti 《对极》2013,45(5):1337-1355
Abstract: The anarchist and geographer Élisée Reclus (1830–1905) argued for the idea of universal brotherhood for all the peoples of the world in his encyclopaedic work the Nouvelle Géographie Universelle (NGU) (1876–1894). The nature of Reclus' argument and its representations of Europe, otherness and colonialism, however, are contested today, and it is unclear what insights it might offer to contemporary students of colonialism and post‐colonialism. In this paper I engage with two emblematic cases—British rule over India and French occupation of Algeria—as they are presented in the NGU, considering Reclus' analysis of imperialism and his novel critique of colonial power. In doing so I wish to demonstrate that far from being conventional, the NGU is a radical and interesting resource for those struggling to construct a critical discourse on Europe, otherness and colonialism.  相似文献   
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