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31.
广州西汉南越王墓和徐州狮子山汉墓是我国汉代最重要和出土玉器数量最多的两个王侯级墓地,两墓出土的丝缕和金缕玉衣是当时南方和中原汉王朝最重要的墓葬玉器之一。通过上手观察、显微镜拍照并利用环境扫描电镜和漫反射红外光谱、拉曼光谱技术对广州南越王墓及徐州狮子山汉墓出土玉衣部分玉片的质材和加工工艺进行了观察测试和对比分析。结果显示,两地玉衣的玉料均主要为透闪石质,从现存玉衣颜色及玉质结构上看,徐州狮子山汉墓出土玉衣玉料来源单一且玉质明显好于南越王墓,南越王墓玉料具有多来源的特征,玉衣中的“假玉”可能来自粤西。从南越王墓玉衣片部分切割痕迹判断,南越王墓所使用的切割工具可能接近当时的最高水平,也可能存在中原交换来源的玉材,无法排除南越王墓玉衣全部或部分在当地制作的可能;南越王墓和徐州狮子山汉墓出土玉衣加工工艺特征明显不同,显示两地玉衣系由不同 “玉作”体系加工完成,汉代可能存在多个不同的玉作体系,工艺水平参差不齐。  相似文献   
32.
In Chinese traditional timber buildings, stitching is very common. When the bearing capacity or the rigidity is inadequate, a timber beam is often strengthened with another beam using the stitching method. The timber stitching beams are mainly of two types—the small-top/big-bottom type and the big-top/small-bottom type. To study the bending behavior of these two types of timber stitching beams, including the failure mode, the flexural capacity, the strain distribution at mid-span section, and the maximum deflection, bending tests are carried out on 14 timber stitching beams with Chinese traditional conformation for seven pine beams and seven fir beams. The results show that the failure modes of the small-top/big-bottom type of stitching beams all show brittle fractures at the bottoms of the bottom beams. The failure modes of the big-top/small-bottom type of stitching beams all show brittle fractures at the bottoms of the top beams. The distribution of section strain along the height of each part of the beam basically obeys plane hypothesis. Based on the theoretical and experimental analysis, the calculation formulas of flexural capacity and maximum deflection of these two types of timber stitching beams made of pine and fir are presented.  相似文献   
33.
Abstract

This special issue addresses the influences of planning cultures and histories on the evolution of planning systems and spatial development. As well as providing an international comparative perspective on these issues, the collection of articles also engages in a search for new conceptual frameworks and alternative points of view to better understand and explain these differences. The articles focus on three main aspects: the change in planning systems and its impact on spatial development patterns; the interrelationship between planning cultures and histories from a path-dependency perspective; and the variations in physical development patterns resulting from different planning cultures and histories. Papers from different parts of the European continent present evidence at different scales to illustrate these aspects. In all cases, the specific combinations of political, ideological, social, economic and technological factors are important in determining urban and regional planning trajectories as well as spatial development patterns.  相似文献   
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Intersectionality is a complex concept to deal with when doing research but also when teaching the interrelationships between space and social relations. Here we present “Relief Maps” as a visual tool for teaching intersectionality and its spatial dimension in higher education courses. “Relief Maps” are a model developed for research and applied in a Geography and Gender course at the Universitat Autònoma de Barcelona (UAB) with the aim of promoting student reflection on the relationships between power structures, places and lived experiences, starting from their everyday lives.  相似文献   
38.
Broca coined the neologism “aphemia” to describe a syndrome consisting of a loss of the ability to speak without impairment of language and paralysis of the faciolingual territories in actions unrelated to speech, such as protruding the tongue or pursing the lips. Upon examining the brains of patients with aphemia, Broca concluded that the minimum possible lesion responsible for aphemia localized to the posterior left inferior frontal gyrus and lower portion of the middle frontal gyrus. A review of Broca’s writings led us to conclude that (a) Broca localized speech, not language, to the left hemisphere, (b) Broca’s aphemia is a form of apraxia, (c) Broca’s aphemia is not, therefore, a terminological forerunner of aphasia, and (d) Broca was an outspoken equipotentialist concerning the cerebral localization of language. Broca’s claim about the role of the left hemisphere in the organization of speech places him as the legitimate forebear of the two most outstanding achievements of Liepmann’s work, namely, the concepts of apraxia and of a left hemisphere specialization for action.  相似文献   
39.
In polycentric urban regions several distinct cities, none of which is dominant, cooperate and compete with each other to attract inhabitants and firms. In such settings city branding strategies do not solely affect one city, but the entire region. We examined how city branding in the face of ecological modernization, that is, delivering higher added economic value, while lowering environmental impacts, is playing out in the Dutch Randstad and the German Rhine-Ruhr. Our findings show that regional identity formation occurs at the sub-polycentric urban region level, coinciding more with (historical) economic profiles than with planning imaginaries. The Dutch cities profile themselves more along the lines of ecological modernization than their German counterparts. Differences between subregions within each polycentric urban region are also noticeable, where more industrialized regions, such as the Ruhr or southern Randstad focus on ‘green’, ‘liveable’ and ‘knowledge-oriented’, while cities with stronger knowledge-intensive sectors portray themselves as ‘smart’ or ‘sustainable’. Cities generally substantiate their profiles through projects, but a significant gap persists between reality and aspirations for improved environmental conditions. This is especially true for the Dutch cities, where many claims, but little visible action can be observed.  相似文献   
40.
This paper argues that portable X‐ray fluorescence spectrometry (pXRF) is a suitable elemental measurement technique to study the production of copper‐alloy artefacts. However, rather than try to imitate the accuracy and precision of laboratory techniques, it is more beneficial to deploy it in a survey role, one that attempts to model chronological and geographical changes within large quantities of artefacts. To achieve this, it was investigated to what extent corrosion and the issues surrounding surface measurements affect the potential of this type of research. Analyses on early Roman period brooches gathered in the Nijmegen region of the Netherlands were subsequently compared with published data.  相似文献   
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