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101.
Beatriz Trinchão Andrade Olga Regina Pereira Bellon Luciano Silva Alexandre Vrubel 《Journal of Cultural Heritage》2012,13(1):28-39
Three-dimensional (3D) digital preservation aims at generating 3D models of objects that have cultural or scientific value. It allows realistic visualization of objects through virtual museums or scientific applications, and the restoration of the preserved object in case of natural wear or accidents. This work contributes to this research area by presenting a method to improve color texture quality of 3D models obtained from color and depth images of a laser scanner. Although this device offers precise depth information, the resulting color information is still poor and limits the generation of realistic textures. Our approach is to capture photographs of the object with a high-resolution digital camera and use them to generate a new color texture for the 3D model. Our work proposes a practical technique, easy to replicate, to generate high quality textures for 3D models from photographs. The method is composed by three main steps: (1) calibration of the image acquisition devices; (2) data acquisition; and (3) texture generation. In this paper, we detail our color texture generation method and apply it on the digital preservation of many artworks made by native Brazilians (indians) from the Wauja and Karaja communities. These indigenous communities are acknowledged as great ceramic artists, each bearing their own main themes, using a very rich symbolism in their paintings. Their artworks represent important aspects of the native South American culture and their digital preservation is motivated by three main reasons: (1) their fragility; (2) the paintings loose their original appearance with time; and (3) the possibility of extinction of these communities. We present several results of preserved artworks with enhanced quality realistic texture maps. Also, we present a methodology to analyze the quality and accuracy of texture maps. The resulting 3D models can be visualized through a tool we developed to support the virtual exhibit of 3D preserved heritage. 相似文献
102.
Beatriz Trinchão Andrade Caroline Mazetto Mendes Jurandir de Oliveira Santos Olga Regina Pereira Bellon Luciano Silva 《Journal of Cultural Heritage》2012,13(2):210-214
We present our recent efforts in the digital preservation of a set of baroque sculptures made by Antônio Francisco Lisboa, known as O. Aleijadinho, which is an important American baroque artist. The set was made in the beginning of the xix century and is composed of 12 near real sized sculptures, hand-carved in soapstone. These sculptures represent 12 of the 16 prophets from the Holy Bible and are part of a UNESCO World Heritage Site. Our group has been collaborating with UNESCO in a project that aims to preserve all these statues. We hereby present our initial efforts, consisting of the 3D digital preservation of the Prophet Joel sculpture. We developed a complete 3D digital preservation pipeline composed of four main stages: data acquisition, 3D reconstruction, texture generation and 3D model visualization. By evaluating our results in this first sculpture, we discuss the improvements we conceived before applying our pipeline in the remaining ones. Finally, we present the 3D model of the Prophet which registers the sculpture's current state and will be used in restoration, research and educational activities. We believe this contribution may be useful to guide further research on similar scenarios, showing how to avoid some practical mistakes and achieve good results. 相似文献
103.
The purpose of this study was to investigate the acute effect of cigarette smoking on cardiac autonomic function in young adult smokers during dynamic exercise. Fourteen healthy young smokers (21.4 ± 3.4 years) performed peak and submaximal exercise protocols under control and smoking conditions. Resting and submaximal beat-to-beat R-R series were recorded and spectrally decomposed using the fast Fourier transformation. Smoking resulted in a significant decrease in work time, VO(2peak) and peak O(2) pulse (P < 0.05). Heart rate increased at rest and during submaximal exercise after smoking (P < 0.05). The raw high frequency and low frequency power were significantly reduced by smoking, both at rest and during exercise (P < 0.05). The low to high frequency ratio was higher after smoking (P < 0.05). The normalised low frequency power was also significantly increased by smoking, but only at rest (P < 0.05). These data demonstrate that the tachycardic effect elicited by smoking is accompanied by acute changes in heart rate spectral components both at rest and during exercise. Therefore, the cardiac autonomic control is altered by smoking not only at rest, but also during exercise, resulting in reduced vagal modulation and increased sympathetic dominance. 相似文献
104.
Miniaturization of immunoassays through microfluidic technology has the potential to decrease the time and the quantity of reactants required for analysis, together with the potential of achieving multiplexing and portability. A lab-on-chip system incorporating a thin-film amorphous silicon (a-Si:H) photodiode microfabricated on a glass substrate with a thin-film amorphous silicon-carbon alloy directly deposited above the photodiode and acting as a fluorescence filter is integrated with a polydimethylsiloxane-based microfluidic network for the direct detection of antibody-antigen molecular recognition reactions using fluorescence. The model immunoassay used consists of primary antibody adsorption to the microchannel walls followed by its recognition by a secondary antibody labeled with a fluorescent quantum-dot tag. The conditions for the flow-through analysis in the microfluidic format were defined and the total assay time was 30 min. Specific molecular recognition was quantitatively detected. The measurements made with the a-Si:H photodiode are consistent with that obtained with a fluorescence microscope and both show a linear dependence on the antibody concentration in the nanomolar-micromolar range. 相似文献
105.
Ruth Da Cunha Pereira 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1997,43(5-6):569-579
The paper focuses on the contribution of action research to teachers' in-service education at elementary schools in the Rio de Janeiro local system of education, linking thought and action indissolubly. This involves inviting teachers and learners to question their own practice, in their own process of building up citizenship, while striving to recover their place in a society that limits and makes their social relations difficult. The development of action research at the Faculty of Education in Rio de Janeiro State University, Rio de Janeiro, Brazil, has brought to light ethical, scientific and political questions in the school system. 相似文献
106.
This paper presents the methodology, results and difficulties encountered in the development and delivery of a course through the Internet. The course, which is about the application of information technology to education, is being delivered using the AulaNet environment, which is groupware for the creation, participation and maintenance of Web-based courses. A model for group work is provided. This paper also shows how this kind of environment can be used to provide support, and to facilitate and manage cooperative learning. 相似文献
107.
Michele Souza Joey Eisenmann Raquel Chaves Daniel Santos Sara Pereira Cláudia Forjaz 《Journal of sports sciences》2016,34(19):1885-1892
In this paper, three different statistical approaches were used to investigate short-term tracking of cardiorespiratory and performance-related physical fitness among adolescents. Data were obtained from the Oporto Growth, Health and Performance Study and comprised 1203 adolescents (549 girls) divided into two age cohorts (10–12 and 12–14 years) followed for three consecutive years, with annual assessment. Cardiorespiratory fitness was assessed with 1-mile run/walk test; 50-yard dash, standing long jump, handgrip, and shuttle run test were used to rate performance-related physical fitness. Tracking was expressed in three different ways: auto-correlations, multilevel modelling with crude and adjusted model (for biological maturation, body mass index, and physical activity), and Cohen’s Kappa (κ) computed in IBM SPSS 20.0, HLM 7.01 and Longitudinal Data Analysis software, respectively. Tracking of physical fitness components was (1) moderate-to-high when described by auto-correlations; (2) low-to-moderate when crude and adjusted models were used; and (3) low according to Cohen’s Kappa (κ). These results demonstrate that when describing tracking, different methods should be considered since they provide distinct and more comprehensive views about physical fitness stability patterns. 相似文献
108.
Valdir De Aquino Lemos Eduardo Da Silva Alves Paulo Adriano Schwingel João Paulo Pereira Rosa Andressa Da Silva Ciro Winckler 《European Journal of Sport Science》2016,16(8):955-964
Body composition is a physiological variable associated with physical activity and, in some cases, is related to athletic performance. Our objectives were to describe the body composition of participants in three distinct Paralympic sports and to compare the values of body density and estimated body fat obtained from the Paralympic athletes on the National Team by air-displacement plethysmography (ADP) and by the anthropometric method (skinfolds (SFs)). The sample consisted of 70 volunteers of both genders. The body composition of the volunteers was evaluated using the ADP in a Bod Pod® and seven SFs. There were no significant differences between the values obtained by ADP and SF for body fat percentage (p?=?.58) and body density (p?=?.49). Analysis by Bland–Altman plots showed mean differences of 0.56?±?4.94 (?9.12–10.23) and ?0.0017?±?0.0113 (?0.024–0.020) for body fat percentage and body density, respectively. In conclusion, body composition analyses of Paralympic athletes by the ADP and SF methods show similar results, and ADP should be used as the first option when available. When the use of ADP is not possible, estimating body density and fat percentage by SF is a viable alternative for Paralympic athletes when future comparisons will use the same analysis method. 相似文献
109.
Alves João Carvalho Luísa Carvalho Renato Correia Florbela Cunha Jorge Farinha Luís Fernandes Joana Ferreira Manuela Lucas Eugénio Mourato Joaquim Nicolau Ana Nunes Sara Nunes Sandra Oliveira Pedro Pereira Cristina Pinto Sandra Silva José 《Tertiary Education and Management》2015,21(2):81-98
Tertiary Education and Management - Higher education institutions and, particularly, polytechnic institutes in Portugal are, generally speaking, recognized as the key stakeholders in regional... 相似文献
110.
Promoting Gypsy children's behavioural engagement and school success: Evidence from a four‐wave longitudinal study 
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下载免费PDF全文 Pedro Rosário José Carlos Núñez Guillermo Vallejo Raquel Azevedo Raquel Pereira Tânia Moreira Sonia Fuentes Antonio Valle 《British Educational Research Journal》2017,43(3):554-571
Low schooling, high non‐attendance and school dropout rates are critical phenomena within disadvantaged groups, especially among the Gypsy community. For example, in the UK, 10%–25% of Gypsy children do not attend school regularly and have significantly higher levels of overall absence from school (percentage of half‐day sessions missed) than pupils from other ethnic groups. In Portugal, available data on Gypsy children is sparse, yet data from one geographic region of the country reports high school failure (45%) and dropout rates (15%) among this population. The present study assessed the efficacy of a four‐year intervention to promote Gypsy children's behavioural engagement and school success. Gypsy communities were contacted and 30 children participating in the four waves were randomly distributed into control and experimental groups. Every school day throughout four years, 16 children in the experimental group were called at home and invited to go to school. The effectiveness of the intervention was evaluated in four waves (at the end of each of the four school years), assessing behavioural engagement (i.e. school non‐attendance, classroom behaviour) and school achievement (i.e. mathematics achievement, student progression). Findings show the efficacy of the intervention on promoting behaviour engagement and academic success without devaluing Gypsy people's culture. 相似文献