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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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A lack of clear political commitment together with confusing rules and enforcement often characterize the institutional context of policy implementation and regulatory compliance in developing countries. By connecting such contextual features to existing models of policy implementation and regulatory compliance, we examine how regulatory factors are related to basic and proactive corporate environmental management practices in the Pearl River Delta region in China. Drawing on data derived from both a survey and in‐depth interviews, we show that a perception of clear political commitment to environmental protection across multiple government levels and units is positively associated with business efforts in basic environmental practices, regardless of the specific enforcement intensity. Nevertheless, a perception of clear political commitment is not related to proactive environmental practices. Conversely, a perception of policy ambiguity, in the form of confusing regulatory standards and enforcement, is negatively associated with corporate efforts in both basic and proactive environmental practices; yet, intensive inspections mitigate these negative associations with policy ambiguity. 相似文献
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正In China,legend says that animals choose different trees to inhabit.In Nagqu,situated on the northern area of the Tibet Autonomous Region,trees are nowhere to be seen,and birds often share holes underground with mice and rabbits.Nagqu means"black river"in Tibetan.The place is situated 相似文献
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2003年3月,笔者在宁波范宅古玩市场收集到一张宁波当地的光绪癸未年金融汇票(如图)及其他借票、除票等若干张。这批票据均是在镇海被发现整理出来的,同时发现的还有清代的田契、税单等,《宁波晚报》2002年11月8日“清代税票现身范宅”曾作报道。 相似文献
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本文认为,晚清时期,圣母圣心会在中蒙古教区获得了持续、稳定的发展。教会的成功既在于其传教方法得当,也在于教会拥有较多的社会资源。怎样评价教会的传教活动,并不是一个容易的话题。 相似文献