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During the 1970's several policy analysts developed estimates of the effect of in-kind transfers (e.g., Food Stamps and Medicaid) on poverty. Unfortunately, many of these studies have, drastically overstated the antipoverty impact of in-kind transfers, leading some to claim that there are no mart? poor people in America. This article reviews these, studies, provides new evidence on the impact of in-kind benefits on poverty, and concludes that there is still a substantial poverty problem in America today which need be addressed by policymakers.  相似文献   
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国内外瓷器修复的基本流程没有很大差异,但是西方国家生产的修复专用材料品种较丰富,值得国内修复界吸收与应用。为此,本研究着重对Hxtal NYL-1、Golden Porcelain Restoration Glaze、Golden Polymer Varnish with UVLS三款瓷器修复专用产品开展分析研究。测试结果显示,在国内外5类环氧树脂中,Hxtal NYL-1的拉伸强度最低,断裂伸长率最高。Hxtal NYL-1在波长365nm的紫外线照射78d后,其色差变化最平稳。紫外可见光谱数据显示Golden Glaze仅吸收一定的中波紫外线UVB,Golden Varnish对长波紫外线UVA和中波紫外线UVB都具有吸收能力。波长365nm紫外老化实验可证明Golden Glaze和Golden Varnish都具备较好的光稳定性。而在254nm紫外老化环境下,Golden Varnish表现出更佳的抗紫外性能。此外,围绕瓷器修复实例,对这些产品的在修复中的使用方法进行了简要梳理。  相似文献   
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Microartefact analysis remains an uncommon practice in archaeology due to the time‐consuming nature of sample processing and analysis and the difficulty of ensuring reliability, replicability, and consistency in material identification and quantification. Work by Huisman et al. (2014) demonstrated the viability of using micro CT (Computed Tomography) to distinguish different kinds of artifactual materials in midden samples, an approach that can help remove “human error” and to speed up the analytical process. However, micro CT samples are limited in size relative to those that can be analysed via High‐Resolution Computed Tomography (HRCT). In addition, the utility of CT techniques for microartefact analysis in different soil types currently is little explored. We present the results of on‐going experimental work using scanning of “cores” containing different sediment matrices and microartefactual materials. Our results are complementary to those of Huisman et al. (2014), showing that microartefacts, including lithic debris, are readily distinguished from enclosing matrices via density class and morphological analysis.  相似文献   
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张云 《史学集刊》2015,(2):60-70
"软权力"的出现是"权力"从国家领域向社会领域流散的结果,侨民和移民作为软权力资源,形成了原籍国和现籍国在非国家领域的"非零和"权力博弈。华人华侨是中国国家软权力建构的基本资源,族群特征、民族习性、文化传统、文明特性是"软权力"建构的基本常量,意识形态、价值观念和政治制度是"软权力"建构的重要变量。中国国家软权力的建构是基于"中国价值观"的探索与实践,华人华侨的社会实践在孕育中国价值观、建构中国软权力中有重要的借鉴意义,要重新审视华人华侨与中国的关系,改变对华人华侨"血统主义"的传统认知,并在制度设计上赢得华人社团等社会性力量的支持。  相似文献   
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Ancient mortars played a crucial role in the construction of historical architectures due to their physical and chemical compatibility with traditional building materials such as stones and bricks. Therefore, the analysis and optimization of the ancient mortar formula are significant in the restoration and preservation of historical sites. In this work, 20 mortar samples selected from five ancient stone pagodas in Zhejiang Province, China, were analyzed. The results showed that mud, lime-soil mortar, lime-sand mortar, and lime-gypsum mortar were used as binders in these pagodas. The Ca(OH)2/aggregate ratio ranging from 0.3 to 2.7 was usually used to prepare lime mortar. Protein and polysaccharide were also found in some samples.  相似文献   
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Measuring the spatial correspondence among geographic features is an important component of many analyses such as those seeking to identify similar or dissimilar features, explore the extent to which change has taken place, and explain the processes influencing spatial change. In networked systems, the paths providing connectivity between pairs of nodes are often the geographic features among which spatial correspondence is to be assessed. That is, given a set of paths between a pair of nodes, the extent to which they share portions of the network and spatially deviate from one another can provide insight on the factors underlying the use of a system. While methods for measuring the spatial correspondence among specific types of network paths have been devised, this article proposes a methodology for measuring the spatial correspondence among the topology of network paths of any type, including those involving redundant use of network space. By basing comparisons upon the topologic relationships among the paths, the proposed approach better accounts for average spatial deviation as well as the asymmetric spatial relationship between pairs of paths, enabling greater stability and consistency in the analysis of their spatial characteristics. The developed methodology is applied to evaluate variability in spatial correspondence among a set of network paths to demonstrate its utility.  相似文献   
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In Papua New Guinea (PNG) more rural people, and especially rural women, earn cash from selling in marketplaces than from any other source. PNG's marketplaces are critical for food security, and for the redistribution of wealth. They are also important meeting places where people gather to see friends, hear the latest news, attend court cases, play cards and be entertained. This introduction to this special issue on ‘Marketplaces and Morality in Papua New Guinea’ reviews the history of PNG marketplaces and their contemporary forms. It charts their transformation from introduced colonial spaces into dynamic Melanesian places, which, as places to buy, sell and socialise, have become pervasive institutions in the lives of both urban and rural Papua New Guineans, and places where people interact with both known and unknown others. From this, marketplaces emerge as important spaces of moral evaluation and contestation in relation to what constitutes morally acceptable exchange and what practices are acceptable in these places. The paper demonstrates that exchange in the marketplace should not be reduced to commodity transactions, and questions assumptions about the types of people marketplaces create. It argues that the country's marketplaces are productive sites to consider ideas of exchange, social relations and social personhood, and that there is a critical need to understand the concrete details of what takes place in contemporary marketplaces.  相似文献   
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