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61.
Dario Ambrosini Claudia Daffara Roberta Di Biase Domenica Paoletti Luca Pezzati Roberto Bellucci Francesca Bettini 《Journal of Cultural Heritage》2010,11(2):196-204
The need of inspecting a masterpiece of fine art without affecting it led to develop non destructive methods of investigation. In the field of art conservation, several diagnostic techniques are being widely used to inspect works of art, giving different but complementary results. The present work deals with two of these methods, reflectography and thermography, both techniques examining objects in the infrared spectrum but in different wavelength bands. Their integrated data potentially provide a powerful tool for mapping hidden features and alterations of artworks. This was confirmed during the inspections of a 13th century panel painting under restoration at the Opificio delle Pietre Dure laboratories (Florence, Italy). A graphical user interface was also designed to aid operators in the field of conservation dealing with the results of the two IR methods. Many options such as image adjustment, comparison, overlaying and transparency variation, in addition to thermographic elaborations, have been made available to users. Imaging data integration provides a multi-layered and multi-spectral representation of the painting that yields a comprehensive diagnosis confirms the anomalies individuation and reduces the ambiguities of information coming from a single diagnostic method. 相似文献
62.
Maintaining the microclimatic parameters at the desired value is essential for artefacts preservation. In order to control the status of the microclimatic parameters, a continuous monitoring of the indoor environmental provides conservators, curators, restorers, and lenders with an exact knowledge of the microclimatic conditions under which the works of art are kept. Moreover, the monitoring results give important information in order to make adequate changes to the control strategy of microclimatic parameters. From this point of view, monitoring is an essential tool to develop an actual preventive control programme aimed at maintaining the optimal microclimatic conditions for preservation. As a consequence, long-term monitoring has to be applied to prevent deterioration of works of art. The widespread opinion that a correct approach to the topic of microclimate control for artefacts preservation is not only and necessarily to provide buildings with sophisticated environmental control systems, but mainly to investigate the actual environmental dynamics and, before any structural intervention, to define the compatibility between the climate control potentials and the preservation requirements, has become more and more firm among the experts. Monitoring also allows to verify the capacity of the “building and Heating, Ventilation and Air Conditioning (HVAC)” system to maintain the desired thermo-hygrometric values within the operating conditions. To this aim, the Italian Standard UNI 10829 (1999) defining monitoring, elaboration and analysis of the microclimatic data as supporting actions for artefacts preservation, led to the need of a long-term monitoring and of a statistical approach to the data management. The approach proposed by the Italian Standard has been recently adopted by a European Standard (EN 15251, 2007). In accordance with the Standards mentioned above, in this paper an operational procedure to assess the thermo-hygrometric quality in museums is firstly synthetically presented and than applied to a case study. In particular, the procedure is developed in order to define the thermo-hygrometric quality level of the exhibition areas in the large museum complex of “Santa Maria della Scala” in Siena (Italy) during the international temporary exhibition “Duccio. La nascita della pittura senese” (“Duccio. The birth of Sienese Painting”). 相似文献
63.
吴迪 《黑龙江生态工程职业学院学报》2017,30(2)
产业聚集形成的集聚效应可以大大提升产业生产效率,对区域的经济发展具有很强的拉动作用.我国自20世纪80年代开始,在沿海地区开始进行产业集聚生产模式的发展,在取得巨大经济利益的基础上,同时也建立了以产业集聚为基础的科技创新平台,形成具有较强创新能力的科技创新网络.基于此,从产业集聚角度分析影响区域创新能力的运行机理,有着较强的实践意义,也可以为区域经济发展提供一定的理论参鉴. 相似文献
64.
Paolo Bardella Irene Carrasquilla García Marco Pozzo Julio Tous-Fajardo Eduardo Saez de Villareal 《Sports biomechanics / International Society of Biomechanics in Sports》2017,16(1):102-114
The purpose of this study was to analyse the raw lifting speed collected during four different resistance training exercises to assess the optimal sampling frequency. Eight physically active participants performed sets of Squat Jumps, Countermovement Jumps, Squats and Bench Presses at a maximal lifting speed. A linear encoder was used to measure the instantaneous speed at a 200 Hz sampling rate. Subsequently, the power spectrum of the signal was computed by evaluating its Discrete Fourier Transform. The sampling frequency needed to reconstruct the signals with an error of less than 0.1% was f99.9 = 11.615 ± 2.680 Hz for the exercise exhibiting the largest bandwidth, with the absolute highest individual value being 17.467 Hz. There was no difference between sets in any of the exercises. Using the closest integer sampling frequency value (25 Hz) yielded a reconstruction of the signal up to 99.975 ± 0.025% of its total in the worst case. In conclusion, a sampling rate of 25 Hz or above is more than adequate to record raw speed data and compute power during resistance training exercises, even under the most extreme circumstances during explosive exercises. Higher sampling frequencies provide no increase in the recording precision and may instead have adverse effects on the overall data quality. 相似文献
65.
通过"亚住高训"交替训练实验,对12分钟极限跑运动中动态心率、血氧饱和度、"极点"等指标进行研究,探讨"亚住高训"模式对"极点"等指标的影响及其提高中长跑运动员有氧工作能力及运动成绩的新途径.方法:对8名大学生中长跑运动员进行6周"亚住高训"实验研究.测试实验前、中、后期的12分钟极限跑、运动中心率、运动中血氧饱和度等指标,并根据运动生理学原理划分12分钟极限跑中机能变化相对应的"极点"等指标及其持续时间.结果:(1)"亚住高训"交替训练前、中、后,12分钟极限跑成绩、最大摄氧量、运动中心率及血氧饱和度等指标变化,呈现有利于有氧工作能力提高的趋势,部分指标存在显著性差异(P<0.05).(2)"亚住高训"实验后,运动员赛前训练12分钟极限跑的"极点"及其持续时间明显缩短、"第二次呼吸"时间延长、"终点冲刺"时间增加,部分指标存在显著性差异(P<0.05).结论:(1)"亚住高训"交替训练能有效提高运动员12分钟极限跑成绩,对运动员有氧工作能力有积极影响.(2)运动中通过心率、血氧饱和度实时检测,能够反映运动中"极点"第二次呼吸"终点冲刺"等指标的变化规律.(3)"亚住高训"交替训练能对12分钟极限跑过程中"极点"第二次呼吸"终点冲刺"及其持续时间的分配进行干预,有助于中长跑运动成绩的提高. 相似文献
66.
The present study examined the generalizability of the factor pattern, structural parameters, and latent structure of a multidimensional hierarchical model of ethnocultural empathy in males and females. The Scale of Ethnocultural Empathy (SEE) (Wang et al., 2003) was administered to a sample of 610 Italian undergraduates to examine the generalizability and reliability of its factor structure across gender, the psychometric properties and the validity of the scale. Two models were tested through multi-group confirmatory factor analysis (MGCFA): a confirmatory factor-analytic model that hypothesized a multidimensional model of ethnocultural empathy; and a structural equation model that proposed a multidimensional, hierarchical structure with global ethnocultural empathy as a superordinate construct that explained the covariances among the subdomains of the SEE. Both models satisfied multiple criteria for goodness-of-fit with the data. Full metric invariance of factor loadings and factor covariances, and partial invariance of error variances across gender for the four-factors model were supported. Scale reliability was also satisfactory, showing good internal consistency. As regard scale validity, evidence was found for a positive moderate association with a measure of general empathy and a negative high association with a measure of prejudice. Implications are discussed. 相似文献
67.
68.
重庆成为直辖市以来,学校竞技体育取得了长足的发展,但还存在许多亟待解决的问题。本文通过对重庆市学校竞技体育的现状进行调查和分析,获得了一些有价值的数据和信息,供相关主管部门参考,以进一步推动学校竞技体育的开展。 相似文献
69.
70.