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61.
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Abstract

Very little site-oriented dendrochronology has been undertaken in Scotland, possibly because of the absence of a locally based dendrochronological facility until recently. However, timbers found during the excavations of several medieval burghs in the late 1970s and 1980s were saved for future analysis and had been stored in museums around the country. During a project to locate suitable samples fir a Scottish tree-ring database the potential of these assemblages was recognised. Although relatively small assemblages, their analysis has expanded and strengthened the tree-ring database within Scotland, thus facilitating future work. Evidence fir synchronous development in the early burghs in the late 12th century and the nature of the woodland resource at times during the medieval period is presented. An 'event horizon' in the early 10th century, signalled by the birth dates of marry of the dated timbers, has been recognised and possible causes are discussed. The projects reported on here were all funded by Historic Scotland.  相似文献   
63.
A distinction between hard-to-shake but rational convictions, on the one hand, and the rationality that calculates causal and logical consequences, on the other hand, can generate questions for the history of ethics. Most moral thinkers draw some such distinction but the contours of the line differ greatly, and, in drawing the line, past moral thinkers tend to be influenced by their own deeply held principles, which in turn tend to reflect their social world. Questions about where the line between values and instrumental calculation are drawn and about the effect on this of the moral thinkers own social world are applied by way of illustration to Thomas Aquinas and Kant. The paper attempts to use Weberian social theory to elucidate a theme in the history of ethics, making every effort to keep the two kinds of theory distinct.  相似文献   
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A well-preserved assemblage of pottery and a broken stone artefact were excavated within a long house in the southern part of Tiszasziget, near the town of Szeged, Hungary. The settlement had been inhabited by the Late Neolithic Tisza culture around 5000–4500 BC. Based on the position of the finds it is suggested that the objects represent an ideologically-charged structured deposition. A piece of organic residue found in a mug (No. 18) with three-fold articulation has been subjected to macro- and microfloral analysis. After precise sampling of the residue, the standard methods to recover organic and inorganic plant remains were utilised. Based on the macrofloral and amino acid content analysis, it is suggested that the organic remains were pieces of fermented pastry made of cereal flour. The recovered silicified tissues and articulated phytoliths were subjected to morphometric measurements, which revealed that the food remain placed in the structured deposition was prepared of Triticum and – probably wild – Avena species. Starch granules of cereals were also detected, whilst the palynological evidence supports morphologies most likely to be related to the accompanying weed flora. The fortunate survival of the organic matter and the complex macro- and micro-archaeobotanical approach provided an unique opportunity to gain a better insight to the food preparation of Late Neolithic communities of the Carpathian Basin.  相似文献   
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This paper outlines the environmental history of the Tigrean Plateau (northern Ethiopia) during the Holocene, based on the available geomorphological, palynological, archaeological, and historical evidence. At present, it seems that (1) the plateau experienced a more humid climate with a denser vegetation cover during the Early Holocene; (2) Soil erosion due to clearing vegetation began in the Middle Holocene; (3) agricultural activity was intensified in the Late Holocene, as a consequence of the rise of a state; (4) demographic pressure increased from the early first millennium BC to the mid–first millennium AD, causing soil erosion; (5) environmental degradation and demographic decline occurred in the late first millennium AD; (6) the vegetation cover was regenerated in the early second millennium AD; and (7) progressive vegetation clearance started again in the second half of the second millennium AD.Cet article trace l'histoire ambiante du Plateau Tigréen dans l'Holocène en utilisant les données géomorphologiques, palynologiques, archéologiques et historiques. Il semble que (1) dans l'Holocène ancien le plateau était caractérisé par une phase humide avec une dense végétation; (2) l'érosion causée par l'abbattage de la végétation commen¸a dans l'Holocène moyen; (3) l'activité agricole s'inténsifia à la fin de l'Holocène, par conséquence de l'essor d'un état; (4) la pression démographique augmenta de plus en plus du début du premier millénaire av. J.-Ch. à la moitié du premier millénaire ap. J.-Ch.; (5) la dégradation ambiante et la diminution démographique se vérifièrent à la fin du premier millénaire ap. J.-Ch.; (6) une régéneration de la vegetation se vérifia au début du seconde millénaire ap. J.-Ch.; et (7) l'abbatage de la végétation recommen¸a dans la seconde moitié du seconde millénaire ap. J.-Ch.  相似文献   
68.
We describe a preliminary survey of a relatively unknown part of the eastern Himalayas: northwestern Sichuan. This survey revealed that three phases of occupation are represented across the landscape. Large settlements with dense remains characterize the landscape during the Neolithic (3400–2000 cal b.c.). Following a hiatus in occupation, stone-cist graves characterize the region during the Bronze Age (1450–800 cal b.c.). The lack of settlement remains from this period indicates that mobile pastoralism increased in importance. Finally, between a.d. 500 and 1500, dense scatters of ceramics over a wide altitudinal range correspond to a fragmentation in Tibetan history, when local warlords established themselves in the region. While some changes in occupation and subsistence practices are linked to climate change, others relate to changes in political power. We argue that further survey work is needed to expand our understanding of past land use and the development of pastoralist practices.  相似文献   
69.
A simple variational formulation for contact dynamics is adopted to investigate the dynamic behavior of planar masonry block structures subjected to seismic events. The numerical model is a two-dimensional assemblage of rigid blocks interacting at potential contact points located at the vertices of the interfaces. A no-tension and associative frictional behavior with infinite compressive strength is considered for joints. The dynamic contact problem is formulated as a quadratic programming problem (QP) and an iterative procedure is implemented for time integration. Applications to analytical and numerical case studies are presented for validation. Comparisons with the experimental results of a masonry wall under free rocking motion and of a small scale panel with opening subjected to in-plane loads are also carried out to evaluate the accuracy and the computational efficiency of the formulation adopted.  相似文献   
70.
We present novel imaging results from a non-invasive examination of three ‘pattern-welded’ swords from the Viking Age belonging to the National Museum of Denmark, using white beam and energy resolved tomographies with neutrons. Pattern-welded blades are made by forge welding together thin strips of iron and steel that were twisted and joined in various ways, producing a decorative pattern on the surface. The study shed light on the inner structure of the composite material and manufacturing techniques of these admired examples of past technology, revealing some otherwise invisible details of their assembly methods, phase distribution and extent of the corrosion.  相似文献   
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