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91.
A geophysical survey was carried out at the ruins of Occhiolà Castle (Sicily, Italy), a medieval village located at the north-western part of a hill named “Terravecchia” at 491 m asl. In order to map the archaeological structures (such as walls and burrows), Electrical resistivity tomography (ERT) and seismic-refraction tomography methods were used. The resistivity variations are known to correlate quite well with the lithology, thus providing important information for identifying the buried archaeological remains. On the other hand, seismic velocity variations provide information about the geometrical features of the remains. The two geophysical methods are used in an enjoined way to better aid the interpretation and evaluate the significance and reliability of the results obtained with each single method. The electrical and seismic data are displayed in three dimensions by using the iso-resistivity and iso-velocity surfaces, respectively. This allows us to effectively define the location of the anomalies present in the single electrical and seismic sections. The results obtained in the survey highlight the presence of structures of regular shape, probably due to features of archaeological interest.  相似文献   
92.
The 15th‐century IJsselcog was lifted in 2016 from the river IJssel near Kampen (the Netherlands). From stern to bow and from starboard to portside about 70% of the original wooden hull is preserved. The combined approach of analogue documentation and photogrammetry enabled the research team to reconstruct the original ship in 2D and 3D, followed by a comprehensive study of its nautical characteristics. The hull volume and height were maximized by the shipbuilders using previously unknown construction elements in cogs, such as wales and vertical riders; shipbuilding traits that are generally applied to 16th‐ and 17th‐century carvel‐built cargo ships.  相似文献   
93.
China's increasing integration into the global pharmaceutical value chain is occurring at a time when big pharma's traditional R&D model has entered a period of crisis, and when China faces significant challenges in providing healthcare for its huge and rapidly ageing population. Despite China's ambitions of promoting its own pharmaceutical sector, it is likely to continue to depend for some time on significant contributions from foreign companies. While this situation provides considerable opportunities for big pharma companies to expand their markets in China, they are also hoping that offshoring aspects of their R&D to China may contribute to reconfiguring their current R&D model with its weak record of producing new drugs. Drawing on interviews with a small number of pharma R&D centres in Shanghai, patent analyses and industry reports, we provide insights into both the challenges and the opportunities associated with the early stages of establishing such centres in an emerging region with a rapidly growing market. This paper contributes towards a more nuanced view of the internationalization of R&D in emerging regions.  相似文献   
94.
在考古工作中的三维重建不仅能更好地展示考古遗址、遗迹与出土文物,还能对其空间信息进行全方位的采集与存档,为后续考古研究、文化遗产保护与展示等工作积累丰富的素材。因此,本研究以带有精细纹理的青铜鼎复制品为例,运用多视角影像三维重建技术,制作三维模型;通过设置控制点建立平面三维坐标系,生成正射影像图、侧视图、断面图、等值线图等数字成果。研究成果可满足考古发掘现场绘图、后期三维展示与定量空间信息的分析等需要,在考古研究及文物保护工作中具有重要的推广价值。  相似文献   
95.
Ancient bones in a good preservation state, ascertained by microscopic techniques, conserve extracellular matrix proteins over thousands of years. With new techniques, intact extracellular matrix proteins from ancient bones and teeth are extracted and separated by one‐dimensional and two‐dimensional electrophoresis. Proteins were identified in Western blots by special antibodies against different human extracellular matrix (ECM) molecules of bone. We have confirmed different types of ECM human bone molecules such as osteonectin, osteopontin, and alkaline phosphatase with specific antibodies in human bone samples from different age groups. Additionally, we selected bone samples from different cultural time periods, such as the Middle Ages, the Bronze Age and the Late Pre‐Pottery Neolithic Phase (PPNB), and teeth from individuals from the Early Middle Ages and from the Late PPNB. The survival of intact extracellular matrix proteins in ancient bones and teeth dating from recent times to the Late PPNB, and reliable techniques to identify these proteins, present a great challenge to further research. A Match Set with PD‐Quest 7.2 shows that only 16% of protein spots in the teeth are also found in the bone of the same individual. In combination with the results of macro‐ and microscopic investigation, biochemical techniques will help us in obtaining a better understanding of bone and teeth in health and disease. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
96.
莫高窟第172窟北壁的建筑图像是敦煌壁画中最具盛唐建筑风格的典型代表作。本研究以探索敦煌壁画中二维建筑图像三维数字化呈现的方法为目标,以第172窟北壁中央的前殿图像为例,综合利用史料文献和实证材料,进行基于有限数据资料与结构逻辑推导的推测性研究,并集成运用图像处理软件(Adobe PhotoShop、Adobe Illustrator)和三维建模软件(SketchUp、Rhino),建立了第172窟北壁中央前殿的三维彩色模型,实现了壁画中的建筑图像从二维到三维的虚拟转变,相对科学、客观地再现了壁画中的建筑形象。通过3D打印等快速成型技术和虚拟投屏等展示利用手段,深度挖掘技术成果价值,扩展了壁画遗产的价值阐释与展示深度,带给观者超现实的空间体验。  相似文献   
97.
In the present study a simple method is described for obtaining 3D digital models of petroglyphs of different sizes and characteristics and its usefulness, in the study of this cultural heritage, is evaluated. For this research we used low-cost photogrammetric software and consumer-grade digital cameras, without any other surveying techniques. In order to test this methodology, three field research studies were carried out in Galicia (Spain).  相似文献   
98.
考古出土的秦始皇兵俑是秦朝十分珍贵的实物资料,具有重大的历史、科学和艺术研究价值,其“千人千面”的特点更是备受关注,被认为是秦人的真实写照。现代人体测量中,头面部特征因其多受遗传因素作用,少受环境因素影响,被广泛应用于分析各民族之间的亲缘关系。通过采集50个样本的兵俑头部高精度三维点云数据并提取了头面部特征,运用样本相关性分析和数据大小排序的统计分析方法,与现代29个群体或地区头面部特征进行了对比研究。结果显示秦始皇兵俑样本的头面部特征完全各异且高度相关,同时与现代群体或地区的头面部特征差异性较小,定量化地明确了秦始皇兵俑的相关特点。  相似文献   
99.
贾湖骨笛是迄今为止我国历史上最早、形态完整、现今仍可演奏的吹管乐器,是9000~7500年前中国古代科技文明最重要的实物载体之一。由于骨笛经历数千年的埋藏,出土时多数已经破损。如何对破损的贾湖骨笛进行精确复制,是学界急待解决的难题。我们巧妙地利用CT扫描、数据处理、三维模型重建、虚拟复原与激光快速成型技术,复原出与M494:2号骨笛实物十分接近复原品。这种利用计算机虚拟修复的思想与技术为破损贾湖骨笛的复原开辟了一条新的技术途径。  相似文献   
100.
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