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21.
ABSTRACT

Lighting a cultural heritage artifact requires balancing visual perception with preventive conservation, by providing the best lighting (in terms of spectral distribution and quantity) to enable the viewer to appreciate details and color, while limiting photo-induced degradation. The paper outlines the methodology applied by a multi-disciplinary team while lighting the Shroud of Turin at its last public exhibition in 2015. The methodology considered the special requirements of the Shroud, including exposure to ultraviolet light, while providing appropriate display conditions that would meet audience expectations. The desired appearance (readability of the body image and color) was defined with the help of Shroud researchers and confirmed by subjective tests, while appropriate light levels for preservation were set in agreement with standard requirements and using knowledge of the degradation of linen in visible and UV light. The installation provided a controlled environment and a managed visitor route to the Shroud, assuring excellent perception of both details and color, with the lowest illuminance level about 15?lx.  相似文献   
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23.
ABSTRACT

Working on preventive conservation in Italy is difficult but not impossible. After small successes and setbacks convincing museums to adopt elements of preventive conservation in the 1990s, the first author (Rossi Doria) was contracted for 15 years to preserve the historic carriages and associated objects of the Presidency of the Republic of Italy. This required patience to overcome or circumvent obstacles such as an inflexible bureaucracy and the absence of any formal recognition of preventive conservation within the educational and contractual systems for heritage conservation. The key factors in his success were the support of the curators, the financial and planning autonomy of the Presidency, and the obvious need for conservation and preservation of these elegant and complex objects. The program began in 2001 with the recovery of the forgotten collection from inappropriate storage in several locations. The entire collection was surveyed and recorded, not only the carriages but also thousands of harnesses, saddles, clothing, fabrics, weapons and memorabilia. Multiple preventive and interventive actions were undertaken, such as pest eradication for all sensitive materials, environmental surveys, and everyday maintenance, as well as complex treatments for the ornate carriages. Analysis by country of published articles on preventive conservation and of IIC membership both confirm that the topic is not as well established in Italy as in many other countries. Some reasons and solutions are proposed.  相似文献   
24.
ABSTRACT

Introduction: Low energy availability (LEA) results in physiological adaptations, which can contribute to unfavourable health outcomes. Little information exists on risk of LEA in active individuals competing in different sports or levels of competition. The aims of this study were to (1) identify risk of LEA in females competing at different levels of competition and (2) investigate associations between risk of LEA, illness and dietary habits. Methods: The validated questionnaire, ‘Low Energy Availability in Females Questionnaire’ was distributed online (November 2016–February 2017) to assess risk of LEA. Twenty-nine additional questions collected information on demographics, illness history and dietary habits. Participants were considered at risk of LEA if they attained a score of?≥?8 and were grouped into: (i) international; (ii) provincial/inter-county; (iii) competitive; and (iv) recreationally active. Chi-square and logistic regression analyses were used to explore differences between those at risk or not at risk of LEA. Results: Risk of LEA was identified in 40% (n?=?331) of 833 participants and was 1.7 and 1.8 times more likely in international and provincial/inter-county athletes compared to those who were recreationally active (International: odds ratios (OR) 1.68, 95% confidence intervals (95%CI) 1.12–2.54; Provincial/inter-county: OR 1.83, 95%CI 1.20–2.77). In participants at risk of LEA, missing >22 days of training during the previous year due to illness occurred 3 times more frequently (OR 3.01, 95%CI 1.81–5.02). Conclusion: Risk of LEA was widespread in this heterogeneous sample. Awareness of LEA and the development of appropriate energy management strategies to ensure athlete health across levels of competition are required.  相似文献   
25.
由于中国和印度都面对着同样的国际环境,且基本国情相似,特别是在能源安全方面都面临着相同或相似的问题,即近年来经济呈现高速和持续增长,能源问题,尤其是石油问题已成为制约中印经济发展的最大瓶颈,中印都积极面向全球部署本国的能源战略,为迅猛增长的经济谋求充足的能源保障。我国的能源战略应向石油进口渠道多样化及多方面与石油输出国乃至消费国加强合作的途径发展。  相似文献   
26.
通过讨论热力学系统在准静态过程ΔE、A、Q诸量与P-V图中过程曲线之间的关系,可直接从P—V图上判断内能的增减、做功正负及热量交换的方向。  相似文献   
27.
本文在文[3]的基础上,进一步给出了包含均熵气体动力学方程组在内的一类2×2拟线性双曲守恒律组的奇性形成结果,证明了在“真正大初值”条件下,Lax定理仍然成立。  相似文献   
28.
关于变频调速的应用与节能分析   总被引:1,自引:0,他引:1  
文章通过分析变频器调速的节能原理,并结合一个热电厂的变频器改造后的实例,阐述了变频调速的节能效果,提高了设备运行可靠性和节能降耗性。  相似文献   
29.
研究分析了Na^ -K^ 在跨膜主动输运过程中,细胞能量(由ATP分解提供)在各阶段的耗散情况.并且把ATP酶视为一个子系统,探讨了其在一个循环中发生的生物物理过程的规律性,对于深入了解细胞生命活动的内在机制提供了一种有益的研究方法。  相似文献   
30.
The Artist Initiative at the San Francisco Museum of Modern Art (SFMOMA) is piloting models for increased collaboration between conservators and curators through joint work with artists. We seek a more integrated, holistic approach to the care and research of our collection. The project, funded by the Andrew W. Mellon Foundation, comprises five robust research engagements that serve the curatorial collecting departments of the museum (Photography, Painting and Sculpture, Media Art, and Architecture and Design). Three of the projects are monographic studies, examining the work of Ellsworth Kelly, Vija Celmins, and Julia Scher in depth, while two more are thematic, exploring modes of displaying digitally-driven design objects, and developing strategies for addressing the problem of color shift common to photographic prints made with experimental materials during the 1970s and 1980s. The Artist Initiative is also charged with developing hybrid working spaces to advance collaborative approaches to collections research at the museum's new downtown campus and at SFMOMA's new Collections Center in South San Francisco. These spaces include the Collections Workroom, a 56?sq?m (600?sq?ft) space that functions as a studio for visiting artists, a conservation laboratory, an interview suite, and a classroom at SFMOMA's downtown campus. At the Collections Center, a 121?sq?m (1300?sq?ft) Mock-Up Gallery has been built as a working model of one of the museum's new galleries. A functional exhibition space, the Mock-Up Gallery is also a venue for interviewing artists, prototyping exhibition formats, and meeting with students, scholars, museum staff, and community members. With the goal of contributing to critical discourses in contemporary art history, art conservation, and public engagement, each of the Artist Initiative projects includes a colloquium that will bring experts from multiple fields together with the featured artists. Thereafter we aim to share our findings widely through public programs and a range of publications, both digitally and in print.  相似文献   
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