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121.
Beatriz Prieto Perla Ferrer Patricia Sanmartín Victor Cárdenes Benita Silva 《Journal of Cultural Heritage》2011,12(4):420
Substitution of slate roofing tiles is a conventional operation during building restoration, since tiles are very difficult to restore or clean because of the high degree of alteration they suffer. Criteria for replacement of historical building stones must be based on geological, geotechnical and esthetic parameters, among which color is of great importance. In this sense, this paper constitutes a comprehensive and useful colorimetric study of roofing slates from the Iberian Peninsula, for the purposes of restoration. The color of 50 commercial varieties of roofing slate mined in quarries from the 12 mining districts in the Iberian Peninsula was analyzed with a spectrophotometer device, by considering the CIELAB color space. The results of the study were used to develop a protocol for characterizing the color of roofing slate and to define the color range of roofing slate from the Iberian Peninsula. In addition, the similarities and differences in the color and microstructure of the different commercial varieties of Iberian roofing slate were established and the limit of acceptability of replacement of one type of slate by another was determined. Parameter hab was found to be the most important CIELAB color coordinate as regards the formation of homogeneous color groups, and the specular component excluded (SCE) mode was most sensitive as regards detecting color differences between two samples. 相似文献
122.
Catherine B. Woods Kevin Volf Liam Kelly Blthín Casey Peter Gelius Sven Messing Sarah Forberger Jeroen Lakerveld Joanna Zukowska Enrique García Bengoechea PEN consortium 《运动与健康科学(英文)》2021,10(3):263-276
BackgroundDespite the well-established health benefits of physical activity (PA) for young people (aged 4–19 years), most do not meet PA guidelines. Policies that support PA in schools may be promising, but their impact on PA behavior is poorly understood. The aim of this systematic review was to ascertain the level and type of evidence reported in the international scientific literature for policies within the school setting that contribute directly or indirectly to increasing PA.MethodsThis systematic review is compliant with Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Six databases were searched using key concepts of policy, school, evaluation, and PA. Following title and abstract screening of 2323 studies, 25 progressed to data synthesis. Methodological quality was assessed using standardized tools, and the strength of the evidence of policy impact was described based on pre-determined codes: positive, negative, inconclusive, or untested statistically.ResultsEvidence emerged for 9 policy areas that had a direct or indirect effect on PA within the school setting. These were whole school PA policy, physical education, sport/extracurricular PA, classroom-based PA, active breaks/recess, physical environment, shared use agreements, active school transport, and surveillance. The bulk of the evidence was significantly positive (54%), 27% was inconclusive, 9% was significantly negative, and 11% was untested (due to rounding, some numbers add to 99% or 101%). Frequency of evidence was highest in the primary setting (41%), 34% in the secondary setting, and 24% in primary/secondary combined school settings. By policy area, frequency of evidence was highest for sport/extracurricular PA (35%), 17% for physical education, and 12% for whole school PA policy, with evidence for shared use agreements between schools and local communities rarely reported (2%). Comparing relative strength of evidence, the evidence for shared use agreements, though sparse, was 100% positive, while 60% of the evidence for whole school PA policy, 59% of the evidence for sport/extracurricular PA, 57% of the evidence for physical education, 50% of the evidence for PA in classroom, and 50% of the evidence for active breaks/recess were positive.ConclusionThe current evidence base supports the effectiveness of PA policy actions within the school setting but cautions against a “one-size-fits-all” approach and emphasizes the need to examine policy implementation to maximize translation into practice. Greater clarity regarding terminology, measurement, and methods for evaluation of policy interventions is needed. 相似文献
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Perceived benefits and barriers to the use of high-speed broadband in Ireland's second-level schools
As part of Ireland's National Digital Strategy, high-speed broadband is being rolled out to all second-level schools to support greater use of information and communication technology (ICT) in education. This programme signals a move from slow and unreliable broadband connections for many schools to a guaranteed high-speed connection with technical support. Theoretically, this should allow for behaviours and pedagogies to adapt, incorporating ICT into education. Research shows that integrating ICT into teaching and learning is a gradual process for most teachers and is influenced by a complex mix of socio-technical factors. Our data set consists of survey data from teachers and principals from a sample of second-level schools. The survey collected factual and attitudinal variables including attitudes towards ICT integration, current availability of infrastructure and barriers to ICT use, before schools received high-speed broadband connectivity. We examine the factors influencing teachers’ attitudes to ICT and their perceived barriers in adopting new technologies in their day-to-day teaching. Analysis of this baseline period is essential in an iterative digital strategy, informing future strategies, targeting policy most effectively and achieving policy objectives. While attitudes towards the potential of high-speed broadband and use of ICT are consistently positive across sub groups of schools and teachers, perceived barriers to ICT usage differ. 相似文献
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Rodolfo herrero Ricaño Héctor Barrón Soto 《The American journal of distance education》2013,27(1):68-71
Abstract Since 1947, distance education in Mexico has had an important role for nonconventional populations. Considering that distance education is a heterogeneous and dynamic field, it is important to reflect on the need to improve quality as measured by our own standards. With that perspective in mind, a national meeting was organized to start a self‐diagnosis in which quality and access were the main concerns. Five hundred and twenty specialists from fifty‐one institutions participated in a national interactive synchronous meeting held in four regions. As a result of the meeting, thirty‐five criteria and 230 parameters of quality were established. The main conclusion of the meeting refers to the need for the elaboration of our own indicators for open and distance education. 相似文献
128.
The objective of this paper is to measure the efficiency of high schools in Tunisia. We use a statistical data envelopment analysis (DEA)-bootstrap approach with quasi-fixed inputs to estimate the precision of our measure. To do so, we developed a statistical model serving as the foundation of the data generation process (DGP). The DGP is constructed such that we can implement both smooth homogeneous and heterogeneous bootstrap methods. Bootstrap simulations were used to estimate and correct the bias, and to construct confidence intervals for the efficiency measures. The simulation results show that the efficiency measures are subject to sampling variations. The adjusted measure reveals that high schools with residence services would have to give up less than 12.1% of their resources on average to be efficient. 相似文献
129.
Néstor Herran 《Science & Education》2012,21(3):335-353
This paper provides a first approach to the history of Ibérica, one of the most important popular science magazines published in Spain before the Civil War. Founded in 1914 by members
of the Society of Jesus based at the Ebro Observatory, Ibérica reached a weekly circulation of about 10,000 in the mid 1920s, and was instrumental in extending science education in Jesuit
education facilities and in developing a “reactionary modernist” culture that embraced Catholicism and modernisation. By focusing
on its coverage of radioactivity and the radium industry, the article aims to examine the magazine’s popularising style and
ideology, and to determine its role in the debates regarding the cultural value of science in the first decades of twentieth
century Spain. 相似文献
130.