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This paper presents the results from extensive parametric dynamic analyses of soil-structure systems that focus on the clear modification (increase or decrease) of the acceleration amplitude at the foundation with respect to the free-field, especially for squatty structures. Properties of the systems are selected such as to cover a wide range of meaningful geometries and materials for engineering practice. The results are presented in terms of weighted modification factors of the maximum foundation acceleration amplitude with reference to the corresponding maximum acceleration amplitude at free-field, for squatty and more slender structures. For the large majority of the studied systems, foundation acceleration decreases from the free-field by 10–15% on average. Nevertheless, acceleration demand at the foundation increases compared to the free-field, for 30% of squatty and for 15% of the more slender structures. Modification of the foundation acceleration amplitude is also correlated with the ratio of the predominant period of the input motion to the flexible-base system period. Finally, the findings of this study are compared with sparse available recorded data from the Seismic Hazard Harmonization in Europe database. 相似文献
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Mauro F. La Russa Michela Ricca Anna Maria Cerioni Maria Grazia Chilosi Valeria Comite Marina De Santis 《International Journal of Architectural Heritage》2018,12(1):114-124
During the last restoration of the Fontana di Trevi -Rome (2014–2015), it has been performed a diagnostic investigation to characterize the materials used to build and obtain the colors of the surfaces of some architectural elements of this fountain. According to the restoration teamwork needs, we focussed our efforts on the dome over the central statue of Oceanus, on the bas-relieves on the sides of the dome, and on the cliff where the water flows. Several samples were collected from these elements and therefore, they were subjected to an analytical approach including infrared spectroscopy, optical and scanning electron microscopy. The achieved results indicated the use of red earth pigments on the dome. The same pigment has been revealed on the bas-relieves, although their colors have an additional contribution due to degraded layers. Samples taken from the cliff showed a complex stratigraphy, although a white scialbo has been identified as original layer, testifying the intentions of the authors in term of color rendering. This information was essential for the restores in order to choose the proper intervention procedure for each investigated surface. The research testified the importance of an integrated diagnostic analysis to preserve the original colours of monuments and building. 相似文献
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Changing patterns of carnivore modification in a landscape bone assemblage, Amboseli Park, Kenya 总被引:1,自引:1,他引:1
This study compares the landscape-scale taphonomic signal of carnivore modification to the surficial bone assemblage in Amboseli Park, Kenya as it was in 1975 and 2002–2004. Change in predator abundances over time provides a means of assessing the taphonomic signal of carnivore-mediated bone consumption and destruction under differing ecological conditions and varying levels of conspecific competition for resources. The landscape assemblage indicates taxonomic variation in the patterning of carnivore modification to ungulates of different size classes as well as within equivalent size classes. Analyses of long bone elements indicate that the differential destruction of limb ends and the strength of the correlation between limb end abundance and bone mineral density provide an indication of the intensity of carnivore modification to a faunal assemblage. The ability to infer levels of carnivore modification based on limb elements can provide faunal analysts with the tools to determine whether the taphonomic signals in the fossil record relate to carnivore modification, hominin transport of appendicular elements, or both. 相似文献
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Gas chromatography (GC), GC-mass spectrometry (GC-MS) and GC-combustion-isotope ratio MS (GC-C-IRMS) analyses of absorbed and surface lipid residues preserved in potsherds were used to explore the extent of pig product processing exploitation in the later British Neolithic Grooved Ware tradition. Assessments were made regarding whether porcine lipids were associated with specific Grooved Ware traits, i.e. decoration, substyle, geographical area and type of site. Two hundred and twenty-two Grooved Ware potsherds were analysed, 70% of which contained lipid concentrations considered significant (>5 μg g−1). All the lipid residues were dominated by animal fats, although plant and beeswax were also detected in a small number of extracts. δ13C values of the major fatty acid components of degraded animal fats (C16:0 and C18:0) were determined for 126 extracts and used to assign ruminant or porcine origins to the residues; 16% of these were found to have a predominantly porcine isotope signature. Statistical associations with pig exploitation were shown to exist with substyle, geographical area and site type, whereas, no relationship was seen between decoration and the type of commodity processed. Intact triacylglycerols were preserved in 19% of the sherds; half of these had distributions consistent with the identifications based on δ13C values, the remainder differed either due to the presence of mixed commodities or because lower molecular weight homologues had been lost due to degradation. In addition to the detection of pig exploitation, results from lipid residue analysis showed a good correlation with faunal assemblages, suggesting that stable isotope analysis may be used as a proxy for animal exploitation at sites where bones have not survived. 相似文献
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Anna M. Cienciala 《国际历史评论》2013,35(1):129-145
The Activities of Polish Communists as a Source for Stalin's Policy Towards Poland in the Second World War 相似文献