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211.
This study focuses on domes the ground plan of which, instead of the more common circular shape, is an oval, and aims at finding the minimally necessary uniform wall thickness for domes of different geometries loaded by their selfweight. The discrete element code 3DEC was applied because of its capability of simulating the collapse mechanisms of masonry structures. Results on the minimal wall thickness, corresponding masonry volume and failure mechanisms for different dome geometries are presented. Three ranges of the friction coefficient were found. For very low frictional resistance collapse happens with pure frictional sliding, for any arbitrarily large wall thickness. In the range of relatively high (i.e., realistic) friction coefficients the structure collapses without any sliding if the wall is not sufficiently thick, and in the observed range of the friction coefficient the necessary wall thickness is nearly insensitive to its value (collapse initiates with hinging cracks only). Between the two domains an intermediate behavior was found: combined cracking and sliding collapse modes occur for insufficient wall thickness, and the minimal thickness strongly depends on the friction coefficient. The critical and transitional friction coefficients separating the failure modes were determined for different eccentricities of the groundplan.  相似文献   
212.
    
This palaeodietary study presents carbon and nitrogen stable isotope data from human and faunal skeletal remains from the Copper Age settlement of Valencina de la Concepción–Castilleja de Guzmán, located in Seville, Spain. Montelirio, the only Valencina–Castilleja human group from which we have obtained reliable palaeodietary results, had a diet based on C3 terrestrial resources, including both plants and animals. The protein component of the diet consisted mainly of meat, milk and dairy products from livestock as well as C3 plant protein from cereals and pulses. This study compares data from Montelirio, the Copper Age group from Valencina–Castilleja, with the published data from other Iberian Late Neolithic–Copper Age (LN‐CA) societies. This comparison reveals a homogeneous diet with some exceptions. Overall, the LN‐CA diet in the Iberian Peninsula consisted mainly of animal proteins from meat, milk and dairy products from livestock as well as C3 plant sources from the characteristic agriculture of the societies of these periods. This study also demonstrates the minor use of aquatic resources from the Neolithic to the Copper Age period in the Iberian Peninsula. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
213.
    
Congenital disorders are pathologies rarely found in archaeological cases. In recent years, however, there has been an increase in the number of reported cases, and a growing interest in understanding their development and implication as genetic markers within certain collections. In the central region of Argentina, researchers have begun to focus on issues related to the health of prehispanic populations from a bioarchaeological perspective. Between 1999 and 2012 our research group recovered, by rescue archaeological activities, a total number of 62 individuals from different archaeological sites in the province of Córdoba, from which only three individuals with pathologies classified as congenital were recorded (4.83%). Radiocarbon and contextual information sets these individuals in the late Holocene (2156 ± 86 and 920 ± 20 14C years BP). Hence, this work aims at presenting two pathological conditions deriving from congenital developmental abnormalities that arise during the first three months of pregnancy: (a) Klippel–Feil syndrome (type II) which was suffered by the individuals from the sites of Guasmara and El Vado, and (b) central sagittal fissure of the vertebral body or ‘butterfly vertebra’ as in the case of one individual from La Calera. We also analyse other lesions in these skeletons that may be associated with the conditions mentioned above, and we provide a thorough interpretation from an osteobiographical perspective. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
214.
    
Here, we present δ13C and δ15N results for the dietary reconstruction of nomadic pastoralists from the Iron Age (ca. 1000 bc –8 ad ) site of Heigouliang. The human (n = 27) δ13C values range from −19.6‰ to −17.0‰ with a mean value of −18.5 ± 0.5‰, and the δ15N results range from 11.5‰ to 13.8‰ with a mean value of 12.4 ± 0.6‰. The results indicated that animals, like sheep, were part of the predominately C3 terrestrial diet, but two individuals have values greater than −18‰ that is indicative of some input of C4 foods in their diets. Because of a lack of faunal samples and to supply complementary information concerning plant consumption, teeth from four individuals were analysed for dental calculus microfossils. Starch grains were found to correspond to Triticeae and Poaceae, possibly including wheat (Triticum aestivum), barley (Hordeum vulgare), highland barley (H. vulgare L var. nudum), foxtail millet (Setaria italica) and/or common millet (Panicum miliaceum). At the population level, no dietary differences were detected between burial owners and sacrificial victims, but variations were found when specific tombs were analysed. In particular, individuals with bone trauma associated with armed conflict also had distinct isotopic signatures possibly suggesting that some of the sacrificial victims could have been captured warriors that were sacrificed for the burial owners. While limited, the results are some of the first from an Iron Age population from Xinjiang and contribute to our understanding of the dietary patterns of this region. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
215.
孙秀莉 《神州》2012,(33):59-60,62
本文以浙江经贸职业技术学院国际贸易实务专业为例,通过对英语听说能力在毕业生就业中的作用以及英语听说教学现状的调查分析,从听说有机整合,融合职业场景和改进教学模式等方面探索英语听说教学改革,以顺应高职英语听说教学的要求,从而更加有效地促进学生英语听说能力的提高。  相似文献   
216.
Sherds from pots found layered under a granite boulder in the Tong Hills of the Upper East Region of Northern Ghana seem, based on their deposition context to have been used for the preparation of medicines. Organic geochemical and isotopic analyses of these sherds and a modern day analogue reveal an n-alkanoic acid composition that is consistent with their being used in the preparation of plant derived substances. Isotopic analyses of the modern medicine pot indicate a contribution of n-alkanoic acids derived from plants that use C4 carbon fixation, most likely maize, sorghum and/or millet suggesting that this pot was used for cooking C4 based plant substances, perhaps, based on current analogy, staple porridge type food. The modern medicine pot could thus have had a prior use. The absence of C4 plant residues in the archaeological sherds suggests that either staple foodstuffs differed radically to today, or, more likely, were not prepared in vessels that were to be used for medicinal purposes.  相似文献   
217.
土城坡墓地位于巫山县旧城区北部,是一处依山傍水的高台地。2005年元月,武汉市文物考古研究所联合巫山县文物管理所对墓地台顶南部大操场及附近地区(Ⅲ区)进行发掘,发掘面积约3571平方米,清理古代墓葬57座。本文主要报道的是Ⅲ区东汉时期4座墓葬的发掘材料。  相似文献   
218.
Geographical Information Systems (GIS) are being incorporated into archaeology as a technique to improve the understanding of spatial organization and the relationships among finds within specific areas. Although their use as a basic tool in predicting the location of archaeological sites or in assessing the extent of their catchment areas is relatively common, in general, they have less often been applied to the study of the spatial distribution of archaeological remains within individual deposits, and in particular to faunal assemblages. Despite this, they can prove essential to understanding dispersion and grouping patterns within deposits fully, and, together with various correlation analytical techniques, they provide valuable information about the economic organization of settlements and inhabitant lifeways. To demonstrate the potential of this methodology, a zooarchaeological GIS has been prepared for the Middle and Late Magdalenian and Azilian layers in El Mirón Cave (eastern Cantabria, Spain), and the spatial distribution patterns of various attributes of the archaeological record have been analysed. Significant conclusions in terms of type and duration of human occupation have been drawn.  相似文献   
219.
This paper describes the multi-disciplinary approach to reconstruct the face of Dante Alighieri (1265–1321). Since Dante's sepulchre will be opened in 2021, the reconstructive process is based on morphological and metric data collected on the poet's cranium during the formal identification of his remains in 1921 by the anthropologist Fabio Frassetto, as well as on the resulting plaster model. Starting from this plaster model and a morphologically compatible reference mandible, since the original mandible was never found, a 3D digital model of the complete skull was obtained by reverse engineering and virtual modelling techniques. The most important aspect in this work was the method of virtual modelling proposed for the ex novo generation of the mandible. The physical model of the skull (cranium + mandible) was then produced by means of a rapid prototyping system. This model was finally used to recreate Dante's face via traditional facial reconstruction techniques currently used in forensic anthropology.  相似文献   
220.
Recent developments in digital technologies are heralding significant changes in the way we acquire, visualise and analyse archaeological data. Terrestrial laser scanners can be used to create photo-realistic virtual copies of landscapes, and archaeological features, and offer the potential to improve our understanding of three-dimensional (3D) spatial relationships at study sites. Here we present a methodology for the integration of a high-resolution 3D site model with soil chemical data obtained from an abandoned settlement site located in the Central Highlands of Scotland. At this site, the multi-element concentration in soil, co-visualised within a topographic setting, has an important role to play in elucidating settlement layout and activity. The methods described here are also of significance in archiving sites of archaeological/historical importance where development activities and/or environmental processes may destroy remains, or where access to field sites is restricted.  相似文献   
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