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191.
Traditional timber frame walls are constructive elements representative of different timber frame buildings, well known as efficient seismic-resistant structures. They were adopted as a seismic-resistant solution in Lisbon’s reconstruction after the 1755 earthquake. To preserve these structures, a better knowledge of their seismic behavior is important and can give indications about possible retrofitting techniques. This article provides a study on possible retrofitting techniques adopting traditional solutions (bolts and steel plates). Static cyclic tests were performed on retrofitted traditional timber frame walls. The experimental results showed the overall good seismic performance of steel plates and the more ductile behavior of bolts retrofitting. 相似文献
192.
Helen Graham Jo Labanyi Jorge Marco Paul Preston Michael Richards 《Journal of Genocide Research》2014,16(1):139-168
193.
José M. Carcione Fabio Cavallini Davide Gei Marco A. B. Botelho 《Journal of Earthquake Engineering》2013,17(1):48-59
We present a detailed approach to implement a moment-tensor point source to compute displacements, particle velocities and accelerations using direct grid methods. Here, the wave modeling algorithm is based on pseudospectral methods to compute the partial derivatives. A comparison to the analytical solution in the 3D acoustic case verifies the discrete implementation of the source in the mesh. Then, the more general 3D elastic case is illustrated and simulations, with and without free surface, are performed that can be used as a reference solution for other grid methods. 相似文献
194.
Jorge Ruiz-García 《Journal of Earthquake Engineering》2013,17(3):449-468
This article presents results of a statistical study focused on evaluating inelastic displacement ratios (i.e., ratio of maximum inelastic displacement with respect to maximum elastic displacement demand) of degrading and non degrading single-degree-of-freedom (SDOF) systems subjected to forward-directivity near-fault ground motions. CR spectra are computed for normalized periods of vibration with respect to the predominant period of the ground motion to provide a better ground motion characterization. This period normalization allows reducing the record-to-record variability in the estimation of CR. An equation to obtain estimates of CR for the seismic assessment of structures exposed to forward-directivity near-fault ground motions is proposed. 相似文献
195.
Fundamental features of the early modern Atlantic – like the slave trade, the rise of experimental science and long‐distance commerce, and the proliferation of religious confessions – were transnational in character. This essay surveys recent work in the field, emphasizing emerging scholarship on the hybrid nature of the Atlantic world. Yet for hybridity to work as a useful analytical category, we need to do away with the narrative of “Northwestern Europeanization” as the normative model. We explore how ecology and place, science and medicine, and diasporic or extra‐national groups like smugglers, Jews, and slaves helped create an Atlantic that was defined more by its cross‐cultural encounters, local contexts, and mixed identities than by the power of European states. 相似文献
196.
Special buildings used as saunas have been found in certain large hillforts in the north of Portugal and in the Cantabrian coastal area of Asturias and Galicia in Spain. The principal aim of this study is to highlight the importance of these buildings in the archaeology and art of the European Iron Age, where they are very rarely mentioned. Two approaches are developed: in Parts 1 and 2, we explain the structure of the buildings, their function, and the current debate surrounding their dating. In Parts 3 and 4, further analyses are developed on their position in the landscape, associating the saunas with the public life of the hillforts, and on the decorative structure of the pedras formosas (‘beautiful stones’) found in some of them, and their relation to certain artistic trends in so‐called Celtic art. 相似文献
197.
Marco Bettiol Valentina De Marchi Eleonora Di Maria Roberto Grandinetti 《European Planning Studies》2013,21(4):498-515
Several studies have emphasized the role of knowledge-intensive business services (KIBS) in fostering innovation in metropolitan areas and regional innovation systems. Such areas are capable of expressing a strong demand for KIBS and consequently stimulate the rise and growth of KIBS. Despite an abundance of literature on KIBS emphasizing the relevance of spatial proximity to customers, many KIBS develop relationships on a broader national or even international scale. No studies have focused explicitly on this apparent discrepancy as yet. The aim of this paper is therefore to fill this theoretical and empirical gap by explaining the firm-level factors relating to the market extension of KIBS within the framework of regional innovation systems. Our analysis is based on a quantitative study on more than 150 KIBS supplying design or communication services located in the Veneto region (north-eastern Italy), an area that can be described as a regional innovation system. Five variables were considered, that is, size, experience, service standardization, investments in network technologies and relational intensity. Our results confirm that three of these variables, but not service standardization and relational intensity, correlate positively with the market extension of KIBS. Policy implications are also discussed. 相似文献
198.
199.
Jorge I. Dominguez 《外交史》2001,25(3):511-516
Book reviewed in this article:
Paul G. Pierpaoli, Truman and Korea: The Political Culture of the Early Cold War 相似文献
Paul G. Pierpaoli, Truman and Korea: The Political Culture of the Early Cold War 相似文献
200.
GPR survey at Lapa do Santo archaeological site,Lagoa Santa karstic region,Minas Gerais state,Brazil
Jorge Luís Porsani Guilherme de Matos Jangelme Renato Kipnis 《Journal of archaeological science》2010
In this work we present and discuss the results of a novel and timely GPR-2D and GPR-3D survey performed at an archaeological rock shelter site, Lapa do Santo, localized in the karstic region of Lagoa Santa, central Brazil. A total of 113 ground-penetrating radar profiles were acquired with 200 MHz and 400 MHz shielded antennas aiming in identifying geological and archaeological anomalies in order to assist archaeologists in an excavation program. The GPR results indicated clear geophysical anomalies characterized by hyperbolic reflections and areas with high amplitude sub-horizontal electromagnetic waves. The anomalies observed by GPR were confirmed by the excavation of test units, allowing the identification anthropogenic features such as a fire-hearth structure and wooden artifact, and natural features, such as, tree roots and rocky bodies such as speleothems, boulders and bedrock. The results showed the efficiency of GPR method in identifying potential buried archaeological targets in cave sites within a karstic area, and they oriented to archaeological excavations, reducing costs and increasing the probability of finding archaeological targets in the initial stages of a project. 相似文献