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71.
This paper continues the characterization of the lead isotopic fingerprint of ancient copper mines in the north‐west of Spain. In this work, the lead isotopic compositions found in copper ores from the La Profunda mine are presented. Azurites and malachites sampled from this deposit were subjected to lead isotope analysis by multicollector ICP–MS. The results showed a clear radiogenic lead signature compatible with the presence of uranium‐rich minerals (such as zeunerite) in the same mining complex. Moreover, a rare copper artefact, found in the galleries of the mine during its modern exploitation, was also analysed and showed that local mineral was used for its manufacturing.  相似文献   
72.
This article presents a method to identify “Absolute and Relative Employment Concentration (AREC) areas” for a particular industry. Two novel characteristics of the method are that it simultaneously analyses AREC, and that it combines spatial concentration per area with the spatial concentration in neighbouring areas. The method is easy to understand and apply. It is developed to assist regional policy makers and corporate decision-makers with their investment decisions related to new infrastructure or plants. The identification of concentration areas also allows for analysing the performance of these areas in relation to characteristics such as infrastructure availability and the housing and labour market. This can yield new academic insights that are relevant for regional planners. An application of the newly developed method to five industries in a Dutch province subdivided into 502 areas illustrates the value of the method in comparison to other methods.  相似文献   
73.
In a talk given at Zurich in the late 1940s, Hermann Weyl discussed Ferdinand Gonseth's dialectical epistemology and considered it as being restricted too strictly to aspects of historical change. His experiences with post-Kantian dialectical philosophy, in particular Johann Gottlieb Fichte's derivation of the concept of space and matter, had been a stronger dialectical background for his own 1918 studies in purely infinitesimal geometry and the early geometrically unified field theory of matter (extending the Mie-Hilbert program). Although now Weyl distantiated himself from the speculative features of his youthful philosophizing and in particular from his earlier enthusiasm for Fichte, he again had deep doubts as to the cultural foundations of modern mathematical sciences and its role in material culture of high modernity. For Weyl, philosophical «reflection» was a cultural necessity he now turned towards Karl Jaspers' and Martin Heidegger's existentialism to find deeper grounds, similar to his turn towards Fichte's philosophy after World War I. The discussion in the late 1940s can be read as a kind of post-World-War-II «Nachtrag» to Weyl's more widely known philosophical comments on mathematics and the natural sciences published in the middle of the 1920s.  相似文献   
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The second half of the 19th century, along with the first three decades of the 20th, saw the building of hundreds of flour mills in Spain, all based on new milling and sieving machinery developed after the industrial revolution. Unfortunately, very few of these early mills are now in use: most have disappeared, and many of those that are left have been abandoned. The present work examines the growth of the flour-milling industry in Spain from the mid-19th century, and discusses the typology, design and constructional features of its associated buildings. The information presented is the result of the study of a representative sample of these mills in central Spain, and could serve as a basis for the conservation, rehabilitation and reuse of this important agroindustrial heritage.  相似文献   
78.
3D surveys of archaeological elements and the construction of virtual models enable us to reconstruct historical sites. They provide useful data to select specific building processes.Photogrammetry and Terrestrial Laser Scanning (TLS) are the most common techniques to obtain synthetically heritage models. These techniques provide massive data which can only be managed by replacing them by primitive shapes, thereby obtaining more simple models and the explicit geometry of the element. Statistical and robust methods are used for this substitution, thereby avoiding the common errors due to measuring. Of these methods, the most widely used are the least-median-of-squares (LMedS) and the RANSAC method.Another computation method consists in recursive processes based on evolutive-type algorithms to adjust the model to the data captured.This paper describes two surface computation methodologies to determine the modelling of a column shaft located in temple G of the archaeological park of Selinunte (Sicily).  相似文献   
79.
In 1918, the Dutch government decided to enclose and reclaim the Zuider Zee (later called the IJsselmeer). The preceding decades had been marked by broad public debate about the utility and urgency of the project. Around 1900, its proponents constructed images of the region and of the Dutch nation in which the Zuider Zee was no longer a crossroads. They emphasized the backwardness of the area and depicted the sea as a domestic enemy, its violent storms posing a threat to the nation. Cornelis Lely’s Zuider Zee proposal (1891) promised a bright future for both the region and the Netherlands as a whole. The struggle against the water would revitalize the nation (by stimulating nation-building) and modernize its international image (perceived as a picturesque but archaic country). Opponents of the project feared the high costs and developed a counter-image: the Zuider Zee region as heartland of ‘authentic’ Dutch culture, a heritage that would be jeopardized by the project. The article concludes by highlighting the synchronicity of the non-synchronous: the Zuider Zee region was envisioned as a region living in the past, thereby constituting an ‘internal Other’ in a country undergoing rapid modernization around 1900.  相似文献   
80.
Proposing a general framework for the study of the emerging transnational society, the article critically surveys predominant disciplinary perspectives in this field, and outlines an approach based on a core/periphery model with oligopolistic competition. Within this general framework, sociology finds its specific subject in the ties that connect human beings across national borders, directly or mediated by transnational institutions. An elaborated and amended version of this approach is illustrated, among others, by the dynamics of cultural globalization and the «world language system».  相似文献   
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