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142.
In this work we present and discuss the results of a novel and timely GPR-2D and GPR-3D survey performed at an archaeological rock shelter site, Lapa do Santo, localized in the karstic region of Lagoa Santa, central Brazil. A total of 113 ground-penetrating radar profiles were acquired with 200 MHz and 400 MHz shielded antennas aiming in identifying geological and archaeological anomalies in order to assist archaeologists in an excavation program. The GPR results indicated clear geophysical anomalies characterized by hyperbolic reflections and areas with high amplitude sub-horizontal electromagnetic waves. The anomalies observed by GPR were confirmed by the excavation of test units, allowing the identification anthropogenic features such as a fire-hearth structure and wooden artifact, and natural features, such as, tree roots and rocky bodies such as speleothems, boulders and bedrock. The results showed the efficiency of GPR method in identifying potential buried archaeological targets in cave sites within a karstic area, and they oriented to archaeological excavations, reducing costs and increasing the probability of finding archaeological targets in the initial stages of a project.  相似文献   
143.
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   
144.
This paper explores how mechanical properties of different South Asian tree taxa might influence charred wood fragmentation and the composition of charcoal assemblages retrieved from archaeological contexts. The dataset is composed of selected plant species that were collected in Gujarat (Northern India) in September 2007 as part of the North Gujarat Archaeological Project. The taxa analysed represent the most common wood species found in the arid thorn scrubland formation in South Asia and are among the most abundant identified in Neolithic and Chalcolithic archaeological sites in this area. The specimens have been measured and subsequently charred at three different temperatures, under constant conditions. Afterwards, their resistance to compression has been measured on two planes, parallel and perpendicular to the direction of fibres, using a Hounsfield 5-kN machine. The tests were performed in order to understand the different response to compressive stress of wood that has been subject to a range of thermal degradations. The standardised treatment applied to the samples has permitted the comparison of results and the delineation of simple correlations and divergences among the species analysed. Furthermore, the utilisation of a relatively simple operating protocol easily allows the addition of further data in the future. The applied protocol was specifically designed to answer archaeological questions. Therefore, even though from a material science point of view some of the measurements were not taken according to the prevailing standard procedures, it offers valuable data for anthracological research applied to archaeology in arid zones.  相似文献   
145.
The island of Nevis in the eastern Caribbean was until recently home to a unique traditional‐built sailing lighter. The last two working vessels were hauled out for the last time only in 2001. The lighters of Nevis have a rich history and were built without plans, conforming to traditional proportions and practices. One of these vessels was carefully documented by the author in the grounds of the Horatio Nelson Museum in Charlestown before it completely succumbed to the elements. The vessels have since deteriorated and are gone. The maritime legacy of Nevis and the lighters are described. © 2012 The Author  相似文献   
146.
耶稣会士郎世宁于1715年至1766年供职于清廷内务府期间,将两种截然不同的艺术文化融合在一起:欧洲艺术风格是这位艺术家所受的基础训练,中国艺术风格则促成了他的职业成就。本文在分析郎世宁意大利基础训练及绘画知识的同时,也分析了其在清廷的代表作品,以提供这位画家在中国进行文化融合的基本框架。郎世宁的文化融合证明,他所接受的意大利基础训练与其后来作为宫廷画家所取得的成就之间,有着深远的联系。本文讨论了郎世宁全部绘画作品中不同元素之间相互关联的动态系统。这些相互关联的元素主要包含三方面的背景:绘画的、政治的以及感性的,分别与三种绘画流派有关——风景画、肖像画以及通景画,这一点对于理解郎世宁的事业至关重要。从更广义的角度讲,本文的目的在于通过展示郎世宁的艺术生涯,有助于我们勾勒出18世纪促成中国与欧洲文化艺术碰撞中的联结点。  相似文献   
147.
This paper presents the theoretical basis and first results of an agent-based model (ABM) computer simulation that is being developed to explore cooperation in hunter–gatherer societies. Specifically, we focus here on Yamana, a hunter-fisher-gatherer society that inhabited the islands of the southernmost part of Tierra del Fuego (Argentina–Chile). Ethnographical and archaeological evidence suggests the existence of sporadic aggregation events, triggered by a public call through smoke signals of an extraordinary confluence of resources under unforeseeable circumstances in time and space (a beached whale or an exceptional accumulation of fish after a low tide, for example). During these aggregation events, the different social units involved used to develop and improve production, distribution and consumption processes in a collective way. This paper attempts to analyse the social dynamics that explain cooperative behaviour and resource-sharing during aggregation events using an agent-based model of indirect reciprocity. In brief, agents make their decisions based on the success of the public strategies of other agents. Fitness depends on the resource captured and the social capital exchanged in aggregation events, modified by the agent’s reputation. Our computational results identify the relative importance of resources with respect to social benefits and the ease in detecting—and hence punishing—a defector as key factors to promote and sustain cooperative behaviour among population.  相似文献   
148.
Herding and farming coexisted in Central Asia for several thousand years as main options of preindustrial economic production. The relationship between people practicing different variants of these modes of subsistence is known to have been dynamic. Among the many possible explanations, we explore this dynamic by modeling mechanisms that connect aggregate decisions to land use patterns. Within the framework of the SimulPast project, we show here the results from step 1 of our modeling program: the Musical Chairs Model. This abstract agent-based model describes a mechanism of competition for land use between farming and herding. The aim is the exploration of how mobility, intensity, and interdependence of activities can influence land use pattern. After performing a set of experiments within the framework of this model, we compare the implications of each condition for the corroboration of specific land use patterns. Some historical and archaeological implications are also discussed. We suggest that the overall extension of farming in oases can be explained by the competition for land use between farming and herding, assuming that it develops with little or no interference of climatic, geographical, and historical contingencies.  相似文献   
149.
Traditional timber frame walls are constructive elements representative of different timber frame buildings, well known as efficient seismic-resistant structures. They were adopted as a seismic-resistant solution in Lisbon’s reconstruction after the 1755 earthquake. To preserve these structures, a better knowledge of their seismic behavior is important and can give indications about possible retrofitting techniques. This article provides a study on possible retrofitting techniques adopting traditional solutions (bolts and steel plates). Static cyclic tests were performed on retrofitted traditional timber frame walls. The experimental results showed the overall good seismic performance of steel plates and the more ductile behavior of bolts retrofitting.  相似文献   
150.
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