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1.
This article aims at presenting and discussing the strategies for updating the finite element numerical modeling of stone masonry arch bridges using operational modal analysis. The study comprehended three bridges: two old ones, the St. Lázaro and the Lagoncinha bridges, and a recently constructed bridge in Vila Fria, Portugal. Updating of the bridge models is performed by comparing the numerical and experimental modal parameters. Three-dimensional detailed numerical models are used to perform modal analysis of the bridges. Experimental modal identification of the bridges is based on the measurement of their acceleration responses during normal operation. The assigned material properties are also based on available results obtained from in situ and laboratory tests and on the results of visual inspection and historical research carried out for both old bridges.  相似文献   
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This study examines an ensemble of Romanesque churches in the region of Val d’Aran in the Spanish Pyrenees, built between the 11th and 13th centuries. Seven topographical studies performed between 2014 and 2015 examined these churches systematically using terrestrial laser scanning (TLS) as a data‐acquisition technique. The data obtained allowed for a geometrically accurate analysis of the orientation of these churches based on four Romanesque liturgies: Gemma animae (c.1120), by Honorius of Autun; Rationale divinorum officiorum (c.1150), by Jean Beleth; Mitralis de Officio (1190), by Sicard, Bishop of Cremona; and Prochiron, vulgo rationale divinorum officiorum (1291), by Guillaume Durand.  相似文献   
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Voltammetry of microparticles using a paraffin‐impregnated graphite electrode (VMP/PIGE) was applied as a very local and non‐invasive analytical technique in order to investigate the presence of remains of metallic plating on two ferrous and one cuprous artefact from the medieval period. The analyses have been performed locally and selectively on regions presenting particular features, such as texture, cohesion and colour differences. The results confirm local differences in chemical composition, leading to conclusions about the presence of metallic plating on these artefacts.  相似文献   
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The fundamental frequency of a structure enables better assessment of its seismic demand for an efficient design and planning of its maintenance and retrofit strategy. The frequency is independent of the type of external loads, however, depends on structural stiffness, mass, damping and boundary conditions. In the case of slender masonry structures such as towers, minarets chimneys, and pagoda temples, it is influenced by mass and stiffness distribution, connection to adjacent structures, material properties, aspect ratio and slenderness ratio. In this present article, the data collected from various literature reviews on the slender masonry structures regarding dynamic, geometrical, and mechanical characteristics have been correlated to identify the major parameters influencing the fundamental frequency of such structures. The database has been used for developing an empirical formulation for predicting the fundamental frequency of such structures. The comparison between the experimental fundamental frequencies and the estimated fundamental frequencies are carried out in order to define reliability and accuracy of these empirical formulae.  相似文献   
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This study presents a method for predicting meagre (Argyrosomus regius) body size (total length) from otoliths and vertebrae recovered from archaeological sites. The method involves regression equations calculated from a reference collection of 36 meagre skeletons and 113 meagre otoliths (sagitta) and allows the simultaneous estimation of original body size and minimum number of individuals (MNI) from archaeological bone structures. We selected the following measurements to predict meagre body size: greatest dorso-ventral height, greatest mediolateral breadth, and greatest anteroposterior length of the vertebrae centra; maximum anteroposterior length, medial anteroposterior length, and dorso-ventral height of the sagitta. Our results show that the original body size of meagre can be accurately predicted from many bone measurements (r2 range: 0.921–0.992). We exemplify the use of the regressions in the assessment of size variation and MNI of meagre from four Portuguese Mesolithic sites. We show that regression results provide additional insight into the significant role that this fish played in the subsistence of coastal fisher-hunter-gatherers, who targeted medium-sized animals but were also capable of acquiring rather larger specimens.  相似文献   
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In Turkey, with the occurrence of almost every strong and even moderate earthquake, damage to masonry minarets is observed. In the present work, efficiency of vertical post-tensioning application to reinforce masonry minarets against earthquakes has been investigated. Considering a representative minaret and its post-tensioned counterpart, and performing spectral and time-history analyses, the effects of post-tensioning on the axial stresses, top lateral displacements and overturning safety have been determined. Obtained results have shown that vertical post-tensioning application is a very efficient method to reduce axial tensile stresses and lateral displacements, and to assure the overturning safety of masonry minarets against earthquakes.  相似文献   
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In this paper, we look at what it means to ‘eat Hawai'i’ and examine how Hawai'i Regional Cuisine (HRC) imagines, produces, and consumes place through particular constructions of local foods. The term ‘local’ attaches to foods as a marker of numerous positive attributes such as seasonal, sustainable, and community-based. Drawing upon ongoing ethnographic research on Hawai'i Island, we examine spatial and discursive constructions of local and how this particular cuisine places itself in local food networks while simultaneously using place to localize itself within the Island's food networks. Using a case study approach to carefully contextualize localness, we show how Merriman's Restaurant and HRC complicate notions of alternative and local food systems in its discursive and material production and reproduction of Local food and locally grown food.  相似文献   
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We have determined the composition of rock art pigments from two megalithic barrows located in the north of Portugal. The use of XRD, SEM–EDS and FT–IR spectroscopy confirmed the presence of hematite and kaolinite in the red pigments from the Eireira barrow, and kaolinite in the white pigment from the Leira das Mamas barrow. The organic composition of the pigments was studied by GC–MS, suggesting that the red sinuous lines and dots from the Eireira barrow were prepared with cooked or heated algae and/or aquatic plants, with egg as binder, while the white pigment from the Leira das Mamas barrow revealed a mixture of vegetable oils for kaolinite moulding, which could be stabilized by temporary exposure to high temperatures. The multi‐analytical approach used on this study of megalithic pigments allowed the recovery of important data about north‐western prehistoric communities, namely the way in which they exploited existing resources and their ability to transform them.  相似文献   
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