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21.
This paper presents a method for estimating edge length from flake dimensions. Comparison of estimated values with data from measured flake edges demonstrates the robusticity of the method. Building on the work of Braun (Braun, D.R., 2005. Examining flake production strategies: examples from the Middle Paleolithic of Southwest Asia. Lithic Technology 30, 107–125; Braun, D.R., Harris, J.W.K., 2003. Technological developments in the Oldowan of Koobi Fora: innovative techniques of artifact analysis and new interpretations of Oldowan behavior, in Mora, R., de la Torre, I. (Eds.), Oldowan: Rather More than Smashing Stones. Treballs d’ Arqueologia 9, pp. 132–144) this estimate is used to generate an edge length to mass value for complete flakes—taken to be a proxy for flaking efficiency. It is shown that this value is useful in tracking the onset, variability and decline of a well known technological phase—the Howiesons Poort of South Africa. The results suggest that the Howiesons Poort was a time in which flaking efficiency was emphasised. Furthermore, comparison of upper limits of edge to mass values for different raw materials may provide an insight into changes in raw material selection.  相似文献   
22.
Microscopy, mass spectrometry and X-ray diffraction methods were used to analyse 415 samples of natural and archaeological flint from Sierra de Atapuerca (Burgos, Spain) in order to define the different types from Neogene and Cretaceous formations in the study area, infer their genetic context and ascertain the supply sources used by hunter-gatherers who exploited this area in the Upper Pleistocene. A statistical classification model was also designed using linear discriminatory analysis and support vector machines which permitted the differentiation of the flint on an age basis.  相似文献   
23.
文物保护技术新世纪展望   总被引:1,自引:0,他引:1  
徐飞 《东南文化》2002,(7):93-96
新世纪中有机氟材料将在物保护领域广泛应用,纳米材抖将从物保护新材料中脱颖而出,抑制微生物腐蚀将成为物保护工作重中之重,互联网将在物保护工作中发挥巨大效率。  相似文献   
24.
谢小羽 《神州》2011,(9X):113-113
创新教育需要渗透到各科教学中。语文学科也毫不例外,并且只有对本学科不断创新,不断注入活水,它才有发展前途,才有存在的必要。语文教学法进行的是母语教学,是一门基础性的、工具性的学科教学。  相似文献   
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Companhia Aurifícia is located in Porto, Portugal, and was founded in 1864. It was a pioneer factory in the industrial production, casting, rolling, and stamping of metallic objects and laboured for about 150 years, in areas as jewelry, manufacture of parts in silver and gold or the production, and casting of various metals. In 1866, it began laboring in Rua dos Bragas, its present location, and in 2003 ceased all activities.Companhia Aurifícia is an industrial complex including several buildings, all located in the same block. It is a precious example of the industrial architecture in Porto, where the still existent retaining walls, structures, machinery, and decorative elements make it one of the last examples of 19th century industrial life of the city.This article aims to evaluate the safety condition of one of the buildings included in this industrial complex, in order to propose the necessary strengthening interventions.  相似文献   
27.
Studies of the ‘geographies of students’ have become increasingly prevalent across the social sciences and are particularly concerned with the predilection for young UK University undergraduates to be mobile in their institutional choice. A more recent focus within this work has been upon student identities, with attention given to how the spaces to which students move and in which they settle can have both positive and negative consequences for the evolution of the student identity, and how such identities are often framed within the context of social activities; learning environments; friendship networks; or other sociocultural factors. This paper contributes to these discussions by considering the role of student accommodation – a site which often remains on the periphery of discussions of student identities – in offering students opportunities to construct, adapt and manage their student identities. This adds to the important contemporary geographies of student accommodation, which are currently debating, among others, purpose-built student accommodation and the broad housing ‘careers’ and strategies of students. In contrast, this paper explores the micro-geographies of student accommodation (and more specifically, the bedroom) to highlight its value in providing young, mobile students with an anchor within which they can draw together their learner, social and domestic dispositions into one geographical location.  相似文献   
28.
化学材料在石质文物保护中的应用   总被引:1,自引:0,他引:1  
综述了目前石质文物保护中所用化学材料的种类、特点及应用,探讨了一些在石质文物保护中有发展潜能的化学材料。有机硅材料、纳米材料和仿生材料具有较好的应用前景。深入研究保护材料与石材的相互作用的微观机理,对于开发适用的石质文物保护材料是非常重要的。  相似文献   
29.
对高校教学管理科学化问题的思考   总被引:4,自引:0,他引:4  
霍云霞 《攀登》2005,24(4):135-136
高校教学管理的科学化是高校教学工作、教学管理工作发展的必然要求,也是高校提高教育质量的基拳保证。本文就高校教学管理科学化的作用、内容、基础、关键、保障等方面进行了粗略的探讨。  相似文献   
30.
中国特色社会主义文化纲领的历史发展   总被引:1,自引:0,他引:1  
从改革开放之初提出"两个文明"建设,到十五大正式提出"经济、政治、文化纲领",再到十六届四中全会发展为"物质文明、政治文明、精神文明、社会文明"四位一体,实质是中国特色社会主义事业总体布局的发展过程,是在这个总体布局中社会主义精神文明建设面临新任务、扮演新角色、承担新使命的过程,是中国特色社会主义文化纲领继往开来、不断丰富发展和完善的过程,反映了中国化马克思主义文化理论一脉相承、与时俱进的理论品质和实践品质。  相似文献   
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