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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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Fran?ois Héran 《Revue de synthèse / Centre international de synthèse》1999,120(1):224-227
Vie Scientifique
Revue d’histoire des sciences humaines 相似文献18.
The main objective of this paper is to suggest an alternative approach for the investigation of domestication in the Levant. First, basic data regarding domestication in the Levant are presented. Then the various traditional approaches towards domestication in the prehistoric Levant, labeled (1) environmental, (2) social and anthropological, and (3) cognitive, are briefly reviewed. This discussion forms the basis for a proposal of a “holistic approach,” in which domestication is regarded as a long-term, multidimensional and multirelational phenomenon, including many elements—such as plants, animals, humans, material culture and ancestors—with increasing human manipulation of these various constituents. After a presentation of the theoretical framework, a growth metaphor is used to reconstruct the process of domestication (ca. 20,000–6500 B.P.) as a number of phases: (1) germination in the Kebaran; (2) development in the Early Natufian; (3) retreat/dormancy in the Late/Final Natufian; (4) growth in the Pre-Pottery Neolithic A; (5) florescence in the Early- and Middle Pre-Pottery Neolithic B: (6) further development in the Late Pre-Pottery Neolithic B; (7) dispersal in the Final Pre-Pottery Neolithic B and the Pottery Neolithic. In each of these phases, relations between the various elements are dealt with, special attention being paid to symbolical relations, as evidenced by “art” and ritual. 相似文献
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Food production originated in various ways in different parts of the world. Plant domestication with the adoption of agriculture has been successful in some areas, but not in others, where animal domestication with nomadic pastoralism proved to be more effective. Likewise, the preceding phases of pre-adaptation and development of a broad spectrum of wild resource exploitation followed different pathways, according to the locally available resources, climatic and geographic conditions, and social organizations. Northern Africa greatly contributed to the understanding of the origin of food production under preconditions that differed from those in the Fertile Crescent. Apart from a narrow strip along the Nile valley, northern African lands are arid and scarcely productive for agriculture. Nevertheless, early studies interpreted northern African archaeological records of the Early and Middle Holocene according to the traditional north-western Mediterranean and Near Eastern frames of reference. Consequently, terms such as Epipalaeolithic, Mesolithic, and Neolithic were uncritically applied to northern African contexts. This paper compares and discusses the evidence for food production in the Near East and northern Africa, considering the question of introduction or local breeds of domesticated animals in the Maghreb and the Sahara. It then reviews the relevant data for long-held diffusionist models of pastoralism into Africa to provide a different perspective and the proper means of interpretation of the northern African archaeological records. Finally, it examines some recent findings from the Tadrart Acacus, in the Libyan Sahara, which contribute to clarification of distinctive African pathways and propose an alternative model for the beginnings of food production. 相似文献
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Eva?Telkes-KleinEmail author 《Revue de synthèse / Centre international de synthèse》2004,125(1):197-215
Building upon Emile Meyerson's correspondence and other personal papers, all of them hosted by the Central Zionist Archives in Jerusalem, this article presents a mainly personal portrait of the philosopher (1859–1933). Thus this article describes his family circle in Lublin (Poland), his higher education (in Germany) and his professional course: settled in France, he worked first in chemistry, then get a job as foreign news editor and later took an important position at the Jewish Colonization Association. This article deals also with Meyerson's contacts with the French and international intellectuel milieu (scientists as well as writers). 相似文献