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1.
Amongst a large number of ancient quarries scattered along the North African coast, those at Sidi Ghedamsy (Monastir, Tunisia) have supplied building stones of Pliocene age. Two lithofacies have been distinguished in the quarry faces: (i) fine sandy limestone, which has been used in the construction of Roman and Arabic monuments; and (ii) porous and coarse limy sandstone, which is of bad quality for construction. Laboratory analysis results confirm that the exploitation of stone in antiquity was well focused on the levels containing the first type. This is confirmed by geotechnical tests, which show that the fine sandy limestone is harder and less porous than the coarse limy sandstone. Extraction of these stones began in the Roman period. The Romans exploited the quarries using steel tools that permitted the extraction of blocks from several levels. In the eighth century, Arabic quarry workers continued the stone extraction using the same technique, but they produced blocks of small and medium size. Statistical measurements have been done on the quarry faces and on the walls of the Ribat in order to understand the degree of conformity between the dimensions of the extracted blocks and those used for building, and ultimately to attempt to date the quarries and the construction of the Ribat.  相似文献   
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Summary.   Epigraphic and isotopic analysis of the lead ingots recovered from a shipwreck off Capo Passero (in Sicily) in mid-2006 suggests that the ingots were produced in Spain, in the Cartagena region. The shipwreck is estimated to have occurred around 38 BC, at the beginning of the Hispanic era. This provides further evidence that the Romans were trading lead throughout the Mediterranean Sea.  相似文献   
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Representations of ships, sailors and seafarers are common in many ancient societies. They were carved, drawn or painted on a great variety of raw materials – stone, wood, metal, textiles and pottery – and can be found in settings such as caves, tombs or royal palaces. Their presence at these sites raises the possibility that these images of maritime life have symbolic or ritual connotations. This paper presents examples of representations of Phoenician and Punic ships from the first millennium BC, in an attempt to understand the role of both their creators and their audiences. These images are subsequently analysed in more detail, focusing on their technical features and their historical contexts. This paper concludes with a consideration of the social and religious aspects of ancient Mediterranean navigation.  相似文献   
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Lead isotope ratios in ore bodies and magmatic rocks depend in a complex way on several a priori independent parameters, including the geological age of the tectonic province in which the ores and magmas formed and its U/Pb (μ) and Th/U (κ) ratios, two very sensitive parameters characteristic of metal sources. All these parameters are entangled in hard‐to‐read Pb isotopic ratios. With respect to the commonly used fingerprinting techniques, which rely on the comparison of raw isotope ratios, the main motivation for the present work is to provide a method for making geologically and geochemically educated guesses about metal provenance even in the absence of isotopic data on reference ores. It shows how to unscramble a geological model age and μ and κ information from isotopic measurements. This approach brings to light a new organization of the Pb isotope database and an untapped wealth of information that can be used for provenance studies and other archaeometric purposes. We provide expressions with which to calculate these parameters and, using literature data, demonstrate how Pb isotopes in ores and magmas define clear zones in the silver‐rich provinces of the Central Andes. We further show how the geological model age and μ and κ values fingerprint production areas in 16th–18th century silver coins minted in Mexico and South America. Finally, we use Pb isotopes to illustrate how the Reconquista of the Emirate of Granada (1482–91) and the seizure of the Betic silver mines are reflected in the silver coins of the Catholic Monarchs.  相似文献   
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This article examines the location of functions within the electricity sector in Canada from 1971 to 2001, using a centre‐periphery model. Power generation, distribution and retailing are generally carried out by multiestablishment crown corporations. Location patterns of different functions—management, scientific, production, etc.—are analyzed via the use of occupational groups. The spatial distribution of functions is found to be generally consistent with centre‐periphery relationships, with evidence of a growing functional specialization between large metropolitan and nonmetropolitan locations. However, differences emerge depending on power generation sources: fossil fuels, hydro, nuclear, solar or biomass. The choice of a power generation source has consequences for local economies.  相似文献   
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Cet article porte sur la relation entre la mondialisation, l'innovation économique et la cohésion sociale au sein des coopératives forestières du Québec dans une perspective de développement régional. Depuis une quinzaine d'années, certaines coopératives forestières au Québec tentent d'innover dans leurs façons de gérer et de produire. Pour innover, ces coopératives s'inscrivent dans un processus de gouvernance avec l'ensemble des acteurs de l'industrie forestière dont l'État, la grande entreprise forestière et les communautés forestières. Cette nouvelle gouvernance semble non seulement permettre aux coopératives forestières d'innover, mais aussi de dynamiser leur capacitéà assurer la cohésion sociale au sein de leurs communautés d'appartenance. La gouvernance forestière apparaît donc comme une stratégie de développement régional pertinente pour les régions qui, comme les régions forestières, sont situées en périphérie et souvent économiquement dévitalisées.  相似文献   
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Restoration requires the use of appropriate characterization methods and suitable new material preparation processes permit the reproduction of the original material to be as similar as possible in order to be an appropriate application method. The combination of these factors will facilitate a good restoration process. Different stuccos were taken from El Museo del Calendario, a building located in Querétaro, Mexico which was built in the 16th century. All the stucco samples were studied using the characterization process which is proposed in this article. The characterization method consisted of the use of analytical techniques, such as X‐ray diffraction, Fourier transform infrared and scanning electron microscopy. This characterization method made reproduction of the original material possible. The new material combined with new application techniques developed in situ will result in a high‐quality restoration process.  相似文献   
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L'objectif de cet article est de comprendre l'évolution des activités aériennes à Montréal. Plaque tournante majeure dans les années 1960, Montréal voit ses activités aériennes ralentir dès le milieu des années 1970. Quelles sont les origines véritables de ce ralentissement? Ce déclin est souvent attribuéà la construction d'un second aéroport international à Montréal‐Mirabel en 1975. Mais qu'en est‐il exactement? Ceci nous amène à nous interroger sur les facteurs de localisation des activités aériennes de manière générale. S'agit‐il d'une activité de service qui se localise selon une logique de places centrales, en fonction de la taille des villes? Faut‐il plutôt chercher ailleurs, par exemple dans les conditions technologiques et réglementaires propres à l'industrie? Pour y répondre, nous proposons une analyse en deux temps. D'abord, nous nous servirons des outils de régression afin d'évaluer l'importance du poids de l'économie locale comme facteur explicatif du trafic aérien. Cette première partie est essentiellement statique. Dans un deuxième temps, nous effectuerons une analyse à caractère davantage historique des activités aériennes de Montréal depuis 1945, pour renouer à la fin avec les résultats de l'analyse de régression.  相似文献   
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