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21.
古建筑三维重建已成为历史遗迹保护与修复的重要内容。为了探讨三维激光扫描数据的获取流程、数据处理方法,以三维激光扫描获取的大雁塔海量点云数据为例,研究了古建筑三维重建中点云数据获取与处理的详细过程。联合Cyclone、AutoCAD和3D-Max软件的优点构建了大雁塔真实的横面、剖面、立面模型,其中重点研究了海量点云数据在Cyclone软件中分块建模的方法。结果表明:将拼接好的大雁塔海量点云数据分块建模,不仅加快了数据处理的速度,而且符合精度要求。在点云数据拼接时采用标靶拼接和同名点拼接相结合及测站间两两拼接之后再整体拟合平差的方法,减少了拼接中的误差,使每站拼接误差都不超过3cm。在建模过程中的墙体拟合是上万个点云经过平差计算得到,精度高达2mm。最后在3D-Max软件中组合、渲染和贴图,真实地构建了大雁塔三维立体模型。为古建筑数字化存档和后期的修缮工作提供了重要的依据。  相似文献   
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Oral cleft (OC) is a common congenital anomaly in humans, which occurs in approximately one per 700 live births. However, cleft skulls are found relatively seldom in archaeological specimens, especially for the bc period. Mortality of infants with OC was apparently high because of breastfeeding difficulties and culturally sanctioned rejection of them in the past. This paper presents one of the most ancient cases of OC in Eurasia. The finding comes from the Middle Bronze Age pastoralists' cemetery in Altai, Russia. The skeletal remains have been radiocarbon dated to 1883–1665 cal bc . Cranial and dental measurements, computed tomography and radiography have been used to examine this malformation. The facial sculpting reconstruction has been performed to visualise the ante mortem appearance of the cleft face. Besides, δ13C and δ15N isotope analysis was used for a comparative study of the diet of the cleft individual. It has been established that a young man from Altai was affected by complete bilateral cleft lip and alveolus, which is a very rare form of typical OC. This defect is associated with dental anomalies such as hypodontia, microdontia, and ectopia as well as with dysmorphology of the facial complex outside the cleft area, including mild hypertelorism, hypoplasia of nasal bones and antheroposterior maxillary deficiency. Furthermore, aplasia of the frontal sinuses and the sacral spina bifida occulta have been observed. These findings are consistent with clinical data indicating strong correlation between development of a major defect and multiple minor anomalies. The results of the study also suggest that there was tolerant attitude towards the facial deformities among the ancient Altai pastoralists. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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Why at this particular historical moment has there emerged a rousing interest in the potential contribution of diasporas to the development of migrant sending states and why is this diaspora turn so pervasive throughout the global South? The central premise of this paper is that the rapid ascent of diaspora‐centred development cannot be understood apart from historical developments in the West's approach to governing international spaces. Once predicated upon sovereign power, rule over distant others is increasingly coming to depend upon biopolitical projects which conspire to discipline and normalize the conduct of others at a distance so as to create self‐reliant and resilient market actors. We argue that an age of diaspora‐centred development has emerged as a consequence of this shift and is partly constitutive of it. We develop our argument with reference to Giorgio Agamben's “Homo Sacer” project and in particular the theological genealogy of Western political constructs he presents in his book The Kingdom and the Glory (2011). We provide for illustration profiles of three projects which have played a significant role in birthing and conditioning the current diaspora option: the World Bank's Knowledge for Development Programme (K4D); the US‐based International Diaspora Engagement Alliance (IdEA); and the EU/UN Joint Migration and Development Initiative Migration4Development project (JMDI‐M4D). Drawing upon economic theology, we make a case for construing these projects as elements of the West's emerging Oikonomia after the age of empire.  相似文献   
25.
The grave of La Balance-Ilot P, in Avignon, southern France, is an individual and isolated burial, attributed in the 1970′s to the Mesolithic or the Early Neolithic. The grave, partially unearthed, was exhibited and stored at the Calvet Museum until its rediscovery and laboratory excavation in 2009. We used 3D laser recording and field anthropological methods, followed by a multidisciplinary approach. The deceased, an adult male, was buried in primary deposition without any architectural features preserved. For the first time in the Mediterranean early Neolithic, this study led to the identification of a garment adorned with sophisticated embroidery using 158 red-colored Columbella rustica shells and 16 red deer canines. Calibrated AMS dates allow us to reliably place it in the early 5th millennium b.c. reinforcing evidence for long distance intercultural relationships in Europe during the Neolithic.  相似文献   
26.
GIS技术在萨拉乌苏考古遗址公园规划设计中的应用   总被引:1,自引:0,他引:1  
传统规划设计工作的技术平台多以计算机辅助设计(CAD)为主,本工作以内蒙古自治区鄂尔多斯萨拉乌苏考古遗址公园规划为例,将Arc GIS Desktop作为技术平台应用到公园的规划设计工作中。首先,通过对规划区的实地踏勘,采集相关数据和资料,进行规划区数据库建设;其次,在数据库建设的基础上,通过GIS技术构建与现实环境对应的虚拟地理信息空间,实现规划区景观的三维可视化;最后,利用三维景观模型对现实地理环境进行模拟、分析及虚拟场景飞行。不同于传统CAD的二维工作平台,本工作借助GIS对空间数据和属性数据的强大处理功能及其三维景观可视化模块,为实现内蒙古鄂尔多斯萨拉乌苏考古遗址公园的科学规划提供辅助。  相似文献   
27.
The ground penetrating radar (GPR) technique was used to investigate the subsurface in an urban area located in Mesagne (Italy) to obtain a map of the archaeological features in the ground. The GPR survey was undertaken at selected locations placed near (about 50 m) to a necropolis dating from the Messapian to the Roman imperial age, using a GSSI Sir System 2 incorporating 200 and 500 MHz centre frequency antennae. The selected areas (A and B) were surveyed along parallel 1 m spaced profiles using a 200 MHz antenna in area A and along parallel 0.5 m spaced profiles using a 500 MHz antenna in area B. For the selected areas the processed data were visualised in 3D space not only by means of the standard time slice technique, but also by means of a recently proposed approach, namely by iso-amplitude surfaces of the complex trace amplitude. The immediacy in revealing the spatial positioning of highly reflecting bodies, such as the anomaly interpreted as an old hypogeum room in area A, makes 3D visualisation techniques very attractive in archaeological applications of GPR. Their sensitivity to the signal/noise ratio is, on the other hand, highlighted by the quite poor performance in area B, where the only reliable result provided by all the techniques was the ancient living surface reflection, whereas none of them could effectively enhance the visibility of weak hyperbola reflections noted on 2D sections and probably related to the walls located on the ancient living surface. The performance of the various techniques in these two different situations allowed insights into their main advantages and drawbacks to be gained.  相似文献   
28.
A 3-D optical scanner was used to obtain precise and complete representations of lithic artifacts. A computer algorithm, which was specially developed for the purpose, was used to position the artifacts in a way which enables the extraction of the standard metric parameters (length, width, width at 1/2 length, etc.). In this way, the ambiguities which affect the traditional manual measurements were eliminated. This new methodology creates accurate and objective databases. Several other parameters (center of mass position, volume, surface area) were also computed. The advantages of our method are illustrated by the analysis of 90 scanned Lower Paleolithic handaxes.  相似文献   
29.
Optically stimulated luminescence (OSL) measurements are reported for single grains of quartz from deposits within Sibudu rock shelter. Such measurements enable rejection of unrepresentative grains and application of the finite mixture and central age models to obtain the most reliable age estimates. Three types of single-grain equivalent dose (De) distributions were observed: one sample represented a single dose population, three samples indicated mixing between Iron Age (IA) and Middle Stone Age (MSA) deposits, and 10 samples (in addition to the three mixed samples) showed scattered distributions. The latter type resulted from differences in the beta dose received by individual grains. For these samples, the beta doses were modelled and adjusted accordingly. Ages for the 14 samples collected from MSA deposits post-dating the Howiesons Poort (HP) resulted in three age clusters, which are stratigraphically consistent with the three informally named cultural phases at Sibudu: namely, the post-HP, late MSA and final MSA. Weighted mean ages of 58.5 ± 1.4 ka, 47.7 ± 1.4 ka and 38.6 ± 1.9 ka were calculated for these phases, respectively. The three phases were separated by two occupational hiatuses with durations of 10.8 ± 1.3 ka and 9.1 ± 3.6 ka. We hypothesise that the punctuated presence of humans at Sibudu was determined by large-scale fluctuations in climate during oxygen isotope stage (OIS) 3, which resulted in alternating wet and dry periods. Phases of occupation correspond to wet periods when fresh water was available in the Tongati River, whereas intervals of site abandonment correspond to dry periods when people were forced to migrate in search of a reliable source of fresh water. Where people migrated to, remains unresolved.  相似文献   
30.
The characterization of a ceremonial bronze axe is described. The axe is assigned to the Santamarian culture of north‐west Argentina, c. 1000–1470 ad, and was selected to increase presently limited knowledge of prehistoric metallurgy in the Andean region of Argentina. The characterization methods used were electron probe microanalysis, gamma radiography, X‐ray diffraction, optical metallography and microhardness testing. The axe was well cast in a bivalve mould, with the only defects in the area of an ancient fracture. The analysis showed that it is made from a tin bronze with a, probably, accidental addition of lead. Arsenic was found as a surface contamination, probably deriving from arsenic in the water of the stream in which the axe was found. The axe shows that Santamarian craftsmen had the skill to decorate the axe in an artistic style with a strong local accent while providing a functional, annealed and cold‐worked cutting edge.  相似文献   
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