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Ancient iron tie-rods are handcrafted elements with large geometric irregularities, due to production techniques (they are shaped by hammering and linked by hot-forging) and corrosion processes. In common practice, their cross section (that is one of the main parameter to assess their strength) is manually measured on site with a manual caliber. By analyzing a set of detailed three-dimensional (3D) digital surveys of real ancient tie-rods, this study provide an evaluation of the errors made by in-situ manual geometric measurements. In particular, it shows that, in some cases, manual on-site survey is sufficiently reliable and has errors that fall below 10%. Moreover, it shows that when tie-rods have high corrosion levels in hidden zones (typically those close or within the retaining walls) the on-site survey of visible parts only may produce far greater errors that exceed 100%, leading to a strong overestimation of the cross-section of the tie. The ongoing study is a first step toward the definition of correction coefficients to be applied to the on-site manual measurements of ancient tie-rods, with the final aim to improve the reliability of structural analyses.  相似文献   
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Tie-rods are essential structural elements, which have been employed for centuries in masonry historical buildings, either during the construction or in successive strengthening interventions, with the aim of containing dangerous horizontal actions. The actual work conditions of these tie-rods, which are strongly influenced by their load history, are difficult to be quantified theoretically, and an effective method for their measure is of great importance in order to ensure the efficiency of these elements during the time and the stability of the entire building. Common measurements are often carried out adopting models based upon significant simplifications, like, for example, hinges at the extremities. These assumptions, rarely represent the real work conditions for anchorages. In this work, a non-destructive testing method is presented, based upon sophisticated dynamical models that can take into consideration many of the circumstances neglected by the simplified models. Four case studies are extensively described, trying to embrace the most common situations in term of peculiar features of the building, structural configuration, and load history. The discussion of the results yields the safety margin of the rod with respect to the material failure and provides important indications about the overall stability of the whole building.  相似文献   
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An archaeological survey of Saudi Arabia's Farasan Islands in May 2010 recorded a broad range of sites that have not previously been documented. The survey concentrated on Greater Farasan and Segid islands, and comprised a rapid recording of sites shown to the authors by representatives of the Saudi Commission for Tourism and Antiquities. The sites were photographed, their positions logged, sketch drawings made of the principal features and surface pottery drawn and photographed. Detailed drawings were made of a stone anchor and a well with possible Ancient South Arabian carved decoration. The sites visited included settlements, wells, cemeteries and a cave. Several sites included the remains of buildings made of massive ashlar blocks, as well as others of rubble‐stone construction. Datable material at the sites points to several periods of occupation, from the early first millennium BC to early modern times. Some locations were characterised by long periods of settlement. Apart from the findings of this survey, most of the sites remain largely uninvestigated, and suggest significant potential for future research into settlement on the archipelago, as well as into past maritime activity and technology in the southern Red Sea region and beyond.  相似文献   
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This article looks at three historical efforts to coordinate the scientific study of biological and cultural aspects of human consciousness into a single comprehensive theory of human development that includes the evolution of the human body, cultural evolution and personal development: specifically, the research programs of Wilhelm Wundt, Lev Vygotsky and Albert Bandura. The lack of historical relations between these similar efforts is striking, and suggests that the effort to promote cultural and personal sources of consciousness arises as a natural foil to an overemphasis on the biological basis of consciousness, sometimes associated with biological determinism.  相似文献   
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This paper examines the return to infrastructure in the European Union regions in a spatial framework. It innovates on the earlier literature on infrastructure and growth by a combination of regional focus, disaggregation of infrastructure types and consideration of spatial dependence. Different types of infrastructure capital are considered as determinants of economic performance at the Nomenclature des Unités Territoriales Statistiques level. To account for growth spillovers among regions, a spatial Durbin model is estimated. The results confirm the important role of infrastructure and identify the highest rates of return as associated with telecommunication, quality and accessibility of transportation networks, with a positive impact of roads and railways.  相似文献   
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The archaeobotanical research carried out in the Iron Age site of Salut (north Oman) gives insights on various interpretative scenarios: the ancient vegetation surrounding the site, oasis farming, and possible ritual practices. The landscape was dominated by dry shrublands with, among others, acacia, jujube and tamarisk that were exploited for obtaining timber and firewood. Agricultural practices mainly consisted of date palm, cereal and sesame cultivation. By comparing the datasets it was possible to assess that the date palm had various uses in this site: one hypothesis involves its offering in ceremonial practices. This third scenario suggests a new way of interpreting some of the plant remains in an archaeological site as Salut, a multipurpose site including a possibly cultic function.  相似文献   
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