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Two sets of twelve Portland limestone tablets were attached to carousels outside and under the open, lightweight shelter at Bishop’s Palace (Witney, England) for 18 months to assess the influence of shelters on soiling and microbiological growth on stone. At the start, and at 6-month intervals, tablets were analysed using microscopy (optical and SEM), colour measurement (spectrophotometry), weight change measurement and salt content determination (ion chromatography). Concentrations of NO2 and SO2 were also monitored for a month using diffusion tubes. In addition, results were compared with those obtained by the UK National Materials Exposure Programme (NMEP) on chemical weathering rates. Differences in soiling and biological growth on sheltered and unsheltered samples, and their influence on limestone decay were established. The shelter is likely to reduce biological growth by modifying the micro-environmental conditions. However, it may also exacerbate dust deposition, which might increase decay rates in the long-term.  相似文献   
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The restoration of paintings on elements in cultural heritage buildings (fundamentally, churches) involves two structural problems: capturing the geometry of the construction element and its development. In many cases, the geometries are regular (e.g., cylinders, spheres, elliptical domes). However, there are cases in which the elements cannot be adapted to any known geometry, much less one that can be mathematically developed. The development of surfaces becomes essential for the restoration of paintings over “flat elements” (over which work is performed on the ground) that are subsequently transferred to the real surface (ceilings). The mathematical transformations that allow regular geometries to be developed are widely known (cartographic projections). However, when the geometry is irregular, there is no development. This study presents a new methodology based on differential rectification and its application for the development of oculi in the Los Santos Juanes Church (Valencia), whose geometry is completely irregular both in shape and as a result of construction defects (and damage caused by fire). The present study focuses on the restoration of paintings damaged by fire.  相似文献   
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孙小龙  林璧属  郜捷 《人文地理》2018,33(1):143-151
旅游体验是游客情感价值的累积。旅游体验质量评价是对游客心理累积情感的测度,科学、准确的核算游客体验质量是旅游景区、旅游企业等可持续发展及竞争力提升的重要保障。本文通过对1980-2015年发表于国内外旅游及管理领域重要期刊文献的梳理,从服务质量研究的历史、科学视角及与旅游融合的角度对旅游体验质量评价的研究进展、理论基础等进行系统的回顾,并从体验质量评价的理论视角、思路、特征、类型与准确性、可操作性、应用范围等中观层面,对所梳理出的4类国外主流质量评价范式进行旅游体验哲学视角下的解读、比较分析和总评,最后对该领域未来研究重点进行展望。  相似文献   
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基于企业网络视角的城市网络研究进展与展望   总被引:4,自引:0,他引:4  
随着生产分割程度的不断加深,企业网络空间增长已经成为城市网络生长发育的重要驱动力量。近30年来,基于企业网络视角的城市网络研究日益增多,在链接关系及时空过程、价值生产空间格局、外部经济及其空间差异、规划实践及治理模式四个方面取得了重要进展。本文在梳理城市网络发展脉络的基础上,从多维视角提出了基于企业网络视角的城市网络理论体系研究框架。总体来看,基于企业网络视角的城市网络研究还处于起步发展阶段。围绕完善理论体系建设,未来研究应着力在5个方面取得进展:城市网络分析技术方法的发展完善、城市网络多维度时空过程的综合比较研究、城市网络发育过程的微观机理解析、城市网络演化模式理论模型研制、城市网络的治理模式和政策框架研究。  相似文献   
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Two new species of benthic foraminifera have been identified from Holocene sediments of the Papuan Plateau. Spirorutilus collinsi sp. nov. (suborder Textulariina) has a rapidly tapering, agglutinated test with depressed sutures, flattened upper chamber surfaces, and a low, broad-arched aperture. The second species, Cibicorbis aspera sp. nov. (suborder Rotaliina), differs from others of the genus in having rugae on both sides of the test, as well as rugose to serrate dorsal sutures.  相似文献   
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Amidst the wide array of women's magazines published in Italy in the 1930s, Lei. Rivista di vita femminile presents a compelling case study of the make-believe effect achieved through fashion and the allure of the silver screen. Published by Angelo Rizzoli between 1933 and 1938, Lei stands out for a cosmopolitan, American-looking lifestyle that champions an Italian ‘new woman’, aware of her own new image and enmeshed in a fantastic world of romantic novels and movie stars. This essay studies the paradoxes and complexities of an Italian illustrated periodical promoting the image of a fashionable woman in the midst of growing imperialism and autarchy, and publishing the work of Leica photographers, Lucio Ridenti and Paul Wolff in particular. Lei reflects the fundamental ambivalence of this time, promoting Italian fashion through Hollywood as a way to counteract the French fashion industry, and inviting women to role-play through the allure of their image.  相似文献   
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The Hui-style residence is an important architectural heritage of China. The hollow wall structures are widely used to build its exterior wall system. However, the thermal performance of the hollow wall is no longer able to meet the new energy-saving and environmental requirement. This article describes a laboratory study of the development of foamed mortar (FM), with the potential for use in thermal upgrading of the Hui-style hollow wall system without dramatically changing its traditional structure. The key early age, physical, mechanical and thermal properties were systematically measured. Two extended models were respectively developed to calculate compressive strength and thermal conductivity, as a function of porosity. Environment chamber test was also employed to investigate the effectiveness of this novel thermal upgrading approach and the results show that filling the voids with FM can effectively improve the overall thermal resistance of the hollow wall system by 44%, which is almost equal to the overall thermal resistance when using the more expensive commercial inorganic stucco system. In addition, the combination of these two methods yielded an overall thermal resistance of 0.701 m2·K/W, which is even higher than 0.67 m2·K/W for the code required in the hot summer/cold winter climate zone.  相似文献   
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This article aims at presenting and discussing the strategies for updating the finite element numerical modeling of stone masonry arch bridges using operational modal analysis. The study comprehended three bridges: two old ones, the St. Lázaro and the Lagoncinha bridges, and a recently constructed bridge in Vila Fria, Portugal. Updating of the bridge models is performed by comparing the numerical and experimental modal parameters. Three-dimensional detailed numerical models are used to perform modal analysis of the bridges. Experimental modal identification of the bridges is based on the measurement of their acceleration responses during normal operation. The assigned material properties are also based on available results obtained from in situ and laboratory tests and on the results of visual inspection and historical research carried out for both old bridges.  相似文献   
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