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51.
The architectural remains at Pasargadae were built of three different stones classified according to their colors (beige, dark-gray, and green-gray). The stones show different macroscopic features, such as texture and decay patterns. The aim of this study is to identify the composition of the stones and to evaluate the main decay factors through petrographic studies in order to make conservation decisions more compatible. Petrochemical analyses show that the stones are in fact limestones with different features; two of them have a compact texture (beige and dark-gray stones), while the third has a fairly porous structure (green-gray stone). In some beige stone samples, dolomite was identified. Despite the fact that the presence of salt is a possible decay factor, X-ray diffraction analysis did not report any salt. According to SEM observations, the main reasons for decay in dark-gray and green-gray stones are the dissolution of calcite crystals and the swelling of clay minerals. The main decay factor in the beige stone, by contrast, is dissolution induced by microorganism activity. However, a patina formed by lichens on the surface of the beige stone, although aesthetically detrimental, protects it against further decay.  相似文献   
52.
The main goal of this work was the non-destructive testing (NDT) of an ancient fresco (15th century) preserved in the Santa Maria di Collemaggio Church (L’Aquila, Italy) and damaged after the 2009 earthquake. Active infrared thermography (IRT), near-infrared (NIR) reflectography and ultraviolet imaging (UV) were used. In addition, the state of the fresco prior to the earthquake was analyzed by electronic speckle pattern interferometry (ESPI), digital speckle correlation (DSC), raking light, tap, and chemical NDT techniques. The use of these techniques was important for the monitoring of new damages and for a comparison between the results over the years. Square heating thermography (SHT) data were processed using principal component thermography (PCT) and pulsed phase thermography (PPT) algorithms, in order to improve the defects’ signature and to reduce the impact of non-uniform heating and emissivity variations due to the painting’s pigments. A multi-analysis approach, segmentation operators and a specific data correlation method emphasize the overall study of the fresco. Furthermore, the facade and the high altar area were inspected by passive thermography and ground-penetrating radar (GPR), respectively. In the present case, the combined use of NDT techniques was useful to fill in the gaps in the construction history of the building.  相似文献   
53.
On évoquera très informellement l’énoncé de quelques résultats récents d’incomplétude des formalismes. Les preuves de ces théorèmes, très importants pour toute l’épistémologie contemporaine des mathématiques, utilisent une variété d’outils conceptuels qui vont démonstrativement au-delà des axiomatisations finitaires. Ces outils ne requièrent aucune ontologie mathématique, mais constituent des constructions humaines particulièrement solides, des formes d’intelligence de l’infini et de l’espace enracinées dans différentes formes de connaissance. On parlera également, mais très brièvement, tant de l’intelligence mathématique du Bon Dieu que de l’intelligence mathématique des ordinateurs digitaux.  相似文献   
54.
Stable isotope analysis of carbon (δ13C), nitrogen (δ15N) and sulphur (δ34S) were carried out on one of the largest assemblages of Late Upper Palaeolithic human remains in Southern Europe, at Grotta del Romito (Cosenza), Italy. The burials were stratigraphically dated from ca. 18,000 to 13,000 cal BP, which was confirmed by a series of new AMS dates made directly on the bone collagen. Dietary reconstruction from carbon and nitrogen stable isotopes revealed that eight of the nine individuals analysed, dating to the Final Epigravettian, had very consistent diets, rich in terrestrial animal protein, regardless of their age or sex. These included two individuals who were suffering from severe pathologies. A single individual, dating to the Evolved Epigravettian had a more variable diet, which was significantly enriched in protein from marine or freshwater fish compared to the later burials. Overall, the results are consistent with the very limited number of other studies which describe a change to more specialised and less variable subsistence strategies, in this case the hunting of large herbivores, towards the end of the Palaeolithic period. Sulphur isotope values of all of the nine burials and several faunal samples were notably consistent, showing no evidence of long-distance migration to the site from a different geological zone.  相似文献   
55.
The hull of the Roman wreck at Grado has been preserved under the cargo of amphoras. On the site, a lot of wooden elements of the rigging are preserved, including deadeyes, blocks, and toggles. Three possible bitts were identified, one of them sculpted; two were nailed to the hull while one was loose. Near the keel a lead tube, protected by a wooden box, has been interpreted as a bilge-pump but more probably it was a suction-pump. The tube would have been connected to a piston pump which has not survived. Possible explanations for its use are presented.
© 2005 The Nautical Archaeology Society  相似文献   
56.
57.
Is there a link between Rome and Barcelona's past and their Olympic legacies? This article sheds further light on the two cities' urban renewals through the Olympics on the basis of a historical and comparative analysis, as well as through the lenses of regime theory. It argues that Rome's modest outcome and Barcelona's success can be linked to their capacity to deal with their controversial past. The article shows that this capacity played a major role in shaping the composition and equilibrium of the two cities' informal networks of local elected officials, bureaucrats and entrepreneurs who planned and implemented the Games (‘growth regimes’). The difficulties of Rome in coping with the Fascist experience resulted in a growth regime in which weak and divided public actors – split along the Fascist/anti-Fascist and Communist/anti-Communist lines – were unable to counterbalance private agents' interests. In contrast, Barcelona's ability to reconcile itself with the past – facilitated by the Spanish entry in the European Economic Community and by the end of the Cold War – eased the Francoist/anti-Francoist and the centralist/Catalan divides, hence allowing the public actors to promote a coalition around a project of ‘democratic restoration’ of the city which involved planners, local businessmen and citizens.  相似文献   
58.
The application of Thermally (TL) and Optically (OSL) Stimulated Luminescence on bricks used as building material has allowed solving an chronological issue in the field of historical building dating. The possibility to use one or more methodologies of dating is closely related to the luminescent and granulometric characteristics of the sample. Using some brick samples collected in the church of Sain Seurin in Bordeaux (France), this paper discusses the implications and the possibility to use different approaches and techniques for dating. With this aim luminescence measurements were performed on both polymineral fine grain and quartz inclusion phases extracted from each brick. For Equivalent Dose (ED) and consequently age determination, TL on mixed fine grain fraction (FG), OSL on quartz inclusions (QI) and on mixed fine grain (FG*) fraction, were used. The results obtained suggest the advantage of using OSL technique on fine grain fraction cleaned up by IR stimulation (FG*), but the use of quartz inclusion represents indeed a good alternative.  相似文献   
59.
A device prototype, based on the superelastic properties of Shape Memory Alloys (SMAs), is proposed to enhance the thermal and seismic behavior of steel tie-rods. First, the thermal behavior of steel tie-rods with and without SMAs is presented based on the results of extensive experimental tests in thermal room. Next, the seismic performances of the proposed SMA system are discussed based on the results of a series of shaking table tests on a 1:4-scale timber roof truss model. In this article, the functioning principles of the proposed SMA-based device prototype are illustrated and the main aspects related to its implementation in practice are discussed in detail. Finally, a recent example of application of the proposed technology to a historic single-aisle church, realized in the 13th century in Brindisi (southern Italy), and equipped with inadequate and deteriorated steel tied rods, is shown.  相似文献   
60.
Italy is experiencing at present the most serious economic recession of the post-war period. Between 2008 and 2013 national income fell by 9 per cent, per capita incomes by 11 per cent, and industrial production by 25 per cent; and unemployment doubled. In this essay we argue that, while this dramatic situation has been made worse by the policies of ‘expansive austerity’, its origins can be traced back to changes that took place in the 1990s (notably globalization, competition for emerging new markets and the diffusion of new technologies – ICT) to which Italy failed to react speedily or effectively by reorganizing its entire productive system. Instead, many of the reforms that have been introduced with respect to the labour market, for example, have reduced costs but in ways that have encouraged firms to stay in traditional sectors where products are poorly differentiated and of low technology content. If the Italian economy is not to become even weaker, new reforms are urgently needed to encourage innovative investment and push through to completion a restructuring of the industrial system that can no longer be deferred.  相似文献   
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