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1.
This essay examines the role of amateurs in founding the astronomical subdiscipline of astrophysics. During 1840–1870, they initiated many of the observing programs that came to comprise the new specialty. And during 1870–1910, they participated both in the ongoing research of the field and the campaign to provide it with an institutional base. These general trends are illustrated by examples from the lives of ten prominent amateur solar physicists.  相似文献   
2.
Scientists advise limiting global warming to 1.5°C with substantial actions by 2030. Our viewpoint argues that climate response strategies in Canada have underemphasized and underestimated the potential contribution deep energy retrofits can make to greenhouse gas (GHG) emissions reductions, leading to inadequate responses in the building sector, and that Canada can (and should) be ambitious with building retrofits over the next decade. GHG savings from building retrofits can be realized more quickly than GHG reductions from other sectors, and either deliver net cost savings or are cost‐effective when compared to other mitigation measures. Retrofits can also provide social and economic benefits, such as improved health and comfort, and lower energy costs. This paper reviews energy use and building retrofits in Canada and argues the following should be implemented: (1) focus innovation on deep energy retrofit processes, not singular retrofit actions; (2) maximize both social and environmental benefits; (3) improve data gathering and availability for analysis and delivery; (4) innovate for a process of decisions and to avoid “dropouts” during the retrofit process; and (5) focus innovation on business models that maximize benefits.  相似文献   
3.
古人发型是文化界长期关注的一个重要现象。发型不仅是时代的特征与时尚的符号,也是各个族群的辨识标志。从北朝到隋唐的中古社会,"剪头胡雏"的文物图像屡屡出现,一般来说,此类胡人形象是剪发而不是束发,在当时以"高髻为尚"的社会习俗中,"剪头胡雏"发型是有着"阶级感"的存在,是有关底层胡人的直观艺术产物。也说明当时入华胡人还没有彻底"汉化",仍然保留着本族群的发型特征。该发式是胡人与汉人的区别,也是其身份归属的象征。  相似文献   
4.
明清丝绸之路哈密—吐鲁番段存在一条自哈密西南沙尔湖转西北至鄯善进而抵达吐鲁番的“沙尔湖路”,它与“黑风川道”“小南路”等传统路线均不同。利用《蒙古山水地图》等文献,可对沙尔湖路具体行经进行考证复原。该路沿线地形平坦,有泉水与植被,在明廷与吐鲁番、清廷与准噶尔在哈密的政治和军事对峙阶段曾广泛使用,后因泉湖干涸、气候炎热而中断。  相似文献   
5.
利用三维扫描技术获取兵马俑残片的三维点云数据,结合Geomagic Studio和Hypermesh建立高精度的兵马俑足踝残片三维实体网格模型。通过基于ABAQUS的重力作用下的有限元分析,研究足踝部分的Von Mises应力和变形特征,以确定足踝处的受力薄弱部位。为进一步探究模型各残片的最佳点云简化比例,采用点云简化模型进行相同工况的有限元分析,以验证点云简化的可靠性。结果表明:结构在重力作用下可保持安全稳定的状态,相对薄弱部位位于左腿足踝处;对于大部分残片,其最佳简化比例在60%~70%,简化后可有效缩短模型实体化处理时间;采用简化模型得到的有限元结果,其最大Mises应力相比于原始模型的误差小于15%,且应力云图和变形图形状接近,模型简化具有可靠性。  相似文献   
6.
Knowledge about the Inca measurement system is based on information from the colonial chronicles and modern studies of the 16th-century Quechua dictionaries. Based on those texts, we can presume that the Incas used an anthropometric system of measurement adopted from the proportions of the human body. Using cosine quantogram analysis and statistical verification, it is possible to verify the existence of the measurement system used by the Inca architects. For this purpose, a measurement series of architectural and water infrastructure elements were collected from 3D point cloud of the Chachabamba and Machu Picchu settlements in Machupicchu National Archaeological Park.  相似文献   
7.
In this review essay, I examine the arguments made by Marnie Hughes-Warrington, with Anne Martin, in Big and Little Histories: Sizing Up Ethics in Historiography. While I find much to praise in this history, I also ask critical questions about the impact of non-Western ethics on historical writing, the role of ethics in historical writing generally, the need to further investigate the everyday lifeworlds of history makers in order to fully understand their ethical dispositions, and the relationship between the ethics of history making and engaged forms of historical writing. I conclude this review essay by offering some reflections on the interrelationship between history and memory and the ethics involved in both.  相似文献   
8.
One of the most intriguing questions for archaeologists studying clay artefacts concerns technologies employed in their manufacture and whether standardization can be demonstrated through traditional ceramic analysis. Visual comparisons and mechanical measurements have been used to determine correlations and infer standardization. Using a laser multi‐line scanner and software developed to quantify Hausdorff distances between vertices in 3D surfaces, we analysed sample collections of figurines and moulds from Belize, Mexico and Honduras. The results indicated that this procedure was a more precise indicator of common source and standardization in moulded clay artefacts. This method provided data relevant to assessing the scope of ancient trade networks and the nature of social and economic relationships that existed among the ancient inhabitants of Mesoamerica.  相似文献   
9.
This paper investigates the function of beauty in David and Bathsheba’s encounter in 2 Sam 11,1-5. It argues that the female bather’s pleasant appearance, rather than simply kindling king David’s desire, focalizes the woman as sexually available (and vulnerable) and wraps the whole episode in a royal fantasy of shared intimacy. The focus on Bathsheba’s beautiful body—her wash, her motion towards the king, her self-sanctification and her pregnancy—frames the episode in a very erotic way, suggesting adultery. It conceals the sexual violence committed by the king who sends, takes and sleeps with the woman. David’s violent entitlement to Bathsheba reveals the beauty politics at play in his royal House.  相似文献   
10.
The child-friendly city advocates for children's ‘right to the city’. Much of this advocacy focuses on the independent child, with little attention paid to the accompanied experiences of younger children, such as those travelling in prams. This paper draws on a material feminist perspective to help address this gap. We offer the concept of mother–child–pram assemblage to bring to the fore the corporeal dimensions of everyday pram journeys. By analysing sensory ethnographic materials collected with mothers and young children living in Wollongong, Australia, this paper highlights how the ‘affective affordances’ and ‘affective atmospheres’ of pram mobilities shape urban experience by reference to how motherhood and childhood are achieved on-the-move. We conclude with policy-relevant insights for the child-friendly city.  相似文献   
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