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441.
This resource paper provides guidance for staff and students on the potential educational benefits, limitations and applications of geotagging photographs. It also offers practical advice for geotagging photographs in a range of fieldwork settings and reviews three free smartphone applications (apps) for geotagging photographs (Flickr, Evernote and Panoramio). Geotagged photographs have the potential to encourage post-fieldwork student reflection on a landscape. A short case study of first-year undergraduates who geotagged photographs as a method of data collection is outlined. This resource paper also briefly discusses the use of student-owned devices in fieldwork which may reduce pressure on departmental budgets.  相似文献   
442.
Time–space compression shows students that geographies are plastic, mutable and forever changing. This paper justifies the need to teach this topic, which is rarely found in undergraduate course syllabi. It addresses the impacts of transportation and communications technologies to explicate its dynamics. In summarizing various conceptual perspectives, the paper illustrates the diverse ways in which it has been theorized. The links between time–space compression and globalization are explored. The paper points to four common pitfalls that plague attempts to teach this issue. It offers five classroom examples through which time–space compression can be taught.  相似文献   
443.
444.
为研究皮质文物鞣制工艺与其组成及物化特性之间的关系,对内蒙古地区皮质文物的种类进行调查、归类。利用扫描电镜、能谱分析等手段对皮质样品的组成及相应的物化特性进行深入的分析研究。结果表明,皮革文物的组成和制作工艺有一定的联系:古代技术鞣制的皮革较现代工艺鞣制的皮革含有较多的四氯化碳提取物和较少的灰分,而现代鞣制皮革含有铬元素,这是现代鞣制的特征。两种皮革样品中都含有食盐,是用来做防腐剂的。  相似文献   
445.
The paper reports the results of an analysis of surface collections of artifacts made at the Luotuoshi site in Dzungaria, Xinjiang, northwest China. The site was discovered in 2004 by a joint Chinese-Russian-American archaeological expedition. A techno-typological analysis of the artifacts was carried out noting aeolian abrasion of the artifacts’ surfaces. This technocomplex is quite homogenous and is characterized by a combination of Levallois-like and subprismatic blade-based reduction techniques. Analogs of the Luotuoshi assemblage have been identified within the lithic industries of the Altai, the Orkhon-1 and Tolbor-4 sites in Mongolia, and at Shuidonggou in the Ningxia Hui Autonomous Region in China, all of which have been attributed to the Early Upper Paleolithic. Luotuoshi is the first site associated with the blade-based Early Upper Paleolithic discovered in northwest China and its particular features make it possible to correlate this technocomplex with those from southern Siberia and northern Central Asia.  相似文献   
446.
Recent studies make use of cortex proportion as a proxy measurement for the impact of artefact transport on assemblage formation. Cortex in these studies is measured on an ordinal scale and analysed in relation to mechanical measurements of artefact size. Here we report on the use of a 3D laser scanner to obtain precise measurements from experimental lithic reduction sets. High-resolution measurements of cortex area are compared to measurements obtained through ordinal approximations of cortex proportion and mechanical approximations of artefact size. While the ordinal and mechanical measurements result in considerable error for individual artefacts, estimates improve significantly as sample size increases.  相似文献   
447.
Detecting and diagnosing the causes of change through time in archaeological assemblages is a core enterprise of archaeology. Evolutionary approaches to this problem typically cast the causes of culture change as being either stochastic in origin, or arising from selection. Stochastic sources of change include random innovations, copying errors, drift and founder effects among dispersing groups. Selection is driven by differences in payoffs between cultural variants. Most efforts to identify these evolutionary forces in the archaeological record have relied on assessing how well the predictions from a neutral-stochastic model of cultural transmission fit a data set. Selection is inferred when the neutral-stochastic model fits poorly. A problem with this approach is that it does not test directly for the presence selection. Moreover, it does not account for the fact that both neutral-stochastic and selective forces can act at the same time on the same cultural variants. A different approach based on the Price Equation allows for the simultaneous measurement of selective and stochastic forces. This paper extends use of the Price Equation to the analysis of selective and stochastic forces operating on multiple artifact types within an assemblage. Ceramic data presented by Steele et al. (2010, Vol. 37(6): 1348–1358) from the Late Bronze Age Hittite site of Bo?azköy-Hattusa, Turkey, provide an opportunity to evaluate the efficacy of this model. The results suggest that selection is a dominant process driving the frequency evolution of different bowl rim types within the assemblage and that stochastic forces played little or no role. It is also clear, however, that we should be attentive to combinations of direct and indirect selective effects within assemblages consisting of multiple artifact types.  相似文献   
448.
Skill is an aspect of prehistoric technology that can inform us on many areas of investigation. This article discusses the notion of skill in prehistoric contexts and how skill is to be formally defined in relation to lithic bifacial tools. The nature of bifacial manufacture entails simultaneous attention to the facial, profile- and cross- section morphology of the core, since each flake removal affects all features. It is argued that bifacial skill can be measured using a multivariate approach, which takes all these features into account. An index measure, the “Bifacial Skill Score”, is proposed and evaluated using both experimental and archaeological data. This measure is argued to constitute a good proxy for skill in bifacial technology and a useful tool for comparative research.  相似文献   
449.
南阳汉代铜舟科学分析   总被引:1,自引:0,他引:1  
本文对一件南阳汉代铜舟进行科学分析,认为其在合金技术、锻造技术、热处理技术和机械加工技术等方面,反映了我国古代青铜技术的先进水平。  相似文献   
450.
"5.12汶川特大地震"对安岳石窟所属的孔雀洞经目塔产生了较大的影响和破坏。本次勘察修缮设计目标是修复经目塔震后的直接残损,对其结构进行必要的加固,减缓风化对塔体的影响,由于破坏的突然性及抢救工作的迫切性要求,从勘察到设计仅仅1个多月时间,勘察设计方在工作之初便决定引入三维激光扫描技术,并在评估及设计过程使用计算机模拟复原技术,力求准确翔实的得出经目塔震后的评估结论,及为震落构件找到准确的原有位置。作为最终修缮设计的依据。并通过结构计算,最终确定经目塔的修缮方案。本次勘察设计过程中引入的三维激光扫描技术及计算机模拟技术在石质文物勘察设计中均具有突破性进展,为今后石质文物的科技保护进行了切实有效的探索。  相似文献   
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