A generative theory of relevance     

Fernando Diaz 《Information Retrieval》2010,13(6):689-692

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Representation of the cell and its processes in high school students: An integrated view     

Fernando Flores  Ma Eugenia Tovar  Leticia Gallegos 《International Journal of Science Education》2013,35(2):269-286

This paper presents an integrated view of the ideas and conceptual problems of high school students with respect to the cell, its processes, structure and relation to the functions of multicellular organisms. The theme of cell has divided into eight topics, with a questionnaire for each topic. In these topics, different levels of representation and understanding are distinguished between general considerations about plants and animals, those connected with processes at organ and system levels and, finally, the level of cell processes. Data from 1200 students were analysed. Results show that students have an analogical mechanism that establishes an isomorphism between the representation of the functioning of multicellular organisms of cell processes. A series of problems in understanding was also shown. Results imply that these problems are mainly due to students' lack of differentiation between some processes at organism and organ level, and have important implications for learning this subject. Finally, some suggestions are made for teaching.  相似文献   

对葡萄牙年轻乒乓球运动员训练结构的研究     

Fernando Malheiro 《体育科研》2005,26(3):37-43,58

从乒乓球国际比赛的情况看,近两年来葡萄牙乒乓球运动员人数显著增加,并且技术水平也明显提高.1996年在巴黎举行的欧洲青年乒乓球锦标赛上,葡萄牙运动员在乒乓球运动史上首次拿到了一枚个人项目的铜牌,实现历史性的突破.从这以后,葡萄牙运动员又多次在国际乒乓球赛事上获得奖牌.然而,如果以20世纪90年代或21世纪初期的情况作参照,不难看出,年轻运动员的技术水平要达到具有取得这样成绩的技术水平还相差得很远.因而,本文在深入调查和了解葡萄牙乒乓球联合会各训练中心年轻乒乓球运动员的训练结构基础上,分析这些训练方式方法是否促进这些年轻运动员协调、快速发展,并在成年时代达到最佳运动技术水平.研究方法本文通过对葡萄牙乒乓球联合会3个训练中心2002至2003年赛季的训练工作的记录文件进行整理,采用文献资料法、调查法、统计法、对比分析的方法进行了研究.主要结果研究分析可知,要使这些年轻运动员在成年时代达到顶尖级水平,这些训练量是不够的;教练员在给运动员的训练安排中主要以技术训练、战术训练和身体素质训练为主,并把重点放在了技、战术的结合方面,其结果还表明运动员在心理因素的训练方面极为不足.另外,在技术、战术、身体素质以及心理训练等各子项的具体内容安排方面也与现代乒乓球运动所要求的特点不相符合.  相似文献   

The democratic dilemma     

Fernando Hernandez 《Journal of Educational Change》2009,10(4):397-400

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Preconceptions and relations used by children in the construction of food chains     

Leticia Gallegos  Maria E. Jerezano  Fernando Flores 《科学教学研究杂志》1994,31(3):259-272

This study shows two aspects: the predator–prey relations and the preconceptions held by children (9–10 years old) on the construction of food chains. The subjects of the study were 506 fourth-, fifth-, and sixth-grade children from the Mexican education curriculum. The conclusions are based on a single application of an instrument after a lecture in the classroom. The instrument consists of three tasks. The outcome showed that the classification of herbivorous and carnivorous is based in children's preconceptions of size and ferocity. These preconceptions guide the children's selection of the higher-level predator in the construction of a food chain. Another element used by children is the predator-prey relation in the construction of a food chain. The results shed light on the difficulties students have at higher education levels in the resolution of food webs and the relationships with ecosystems.  相似文献   

High-Resolution Ultrasonic Imaging of Artworks with Seismic Interferometry for Their Conservation and Restoration     

Deyan Draganov  Jürg Hunziker  Karel Heller  Karin Gutkowski  Fernando Marte 《文物保护研究》2018,63(5):277-291

Artworks are an inseparable part of the cultural heritage of societies and provide us with a unique look at cultural developments through time and space. For the best possible conservation, it is paramount to know the constituent materials, condition, and construction techniques of the objects (e.g. painting on wood, fresco, sculpture). Such information is required not only for the surfaces of the objects, but also for the interiors; in the imaging discipline, this is known as depth imaging. Here, we introduce a new method for non-invasive depth imaging as an alternative to traditional non-invasive methods when the latter cannot be used to obtain the required information. We use ultrasonic transverse-wave transmission measurements and turn them into virtual reflection measurements. We achieve this by applying seismic interferometry with active sources. Obtaining reflection measurements by seismic interferometry allows us to apply an advanced imaging technique – prestack depth migration, as used in seismic exploration – to produce a high-resolution depth image of an object. We apply our method to ultrasonic data recorded on a mockup of a painting on a wooden support. We validate our method by comparing our results with an image from X-ray computed tomography.  相似文献   

The impact of the debt crisis on education in Latin America     

Fernando Reimers 《Prospects》1990,20(4):539-554

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Development and initial validation of a scale to measure emotional abuse among school children aged 13-15 years in Sri Lanka     

Fernandopulle S  Fernando D 《Child abuse & neglect》2003,27(10):1087-1099

OBJECTIVE: To develop a scale to measure emotional abuse among school children aged 13-15 years in Sri Lanka that can be used in field settings. METHOD: Emotional abuse was defined based on available literature. Review of literature and discussions with a panel identified 85 items indicating abusive behaviors. Content validity and social acceptability were achieved by getting the views of this same panel and parents, respectively. Item analysis and assessment of validity were carried out based on the responses to the draft instrument by 105 children aged 13-15 years attending a school in an urban slum area. The test-retest reliability of the scale was assessed using the responses from 144 students from a different school. Criterion validity was established by comparing the independent assessments of a psychiatrist for the presence or absence of emotional abuse with the respective scores of the children on the scale. RESULTS: The scale developed to assess emotional abuse included 46 items having a Cronbach alpha of .89. The test-retest reliability was .73. A cutoff score of 95 was identified at a sensitivity of 76.9% and a specificity of 51.4%. CONCLUSIONS: A scale that had a satisfactory level of reliability and validity was socially acceptable, which could be used in school settings in Sri Lanka was developed to enable identification of emotional abuse among school children aged 13-15.  相似文献   

Predictor variables of written picture naming in the deaf     

Fernando Cuetos  Asunción Monsalve  Alejandro Pinto  Javier Rodríguez-Ferreiro 《Reading and writing》2004,17(3):227-240

Studies conducted in recent years on oral andwritten language production show that the ageat which words are learned is the main variablethat influences lexical access in both hearingpeople and people who have suffered brainlesions. No studies have been done with deafpeople and, since they use sign language inaddition to oral language, differencesregarding hearing people might be found intheir lexical organization. The aim of thisstudy was to test which variables determine thelexical production of deaf people. For thispurpose, 40 deaf people between the ages of 13and 58 years were asked to write individuallythe names of 100 pictures. The regressionanalyses performed on a total of 4000 responsesshow that the main predictor variable ofperformance was also age of acquisition. It isconcluded that the organization of the lexicalsystem in deaf people is similar to that of hearing people, although the phonologicalrepresentations of deaf people may be moreinaccurate.  相似文献   

Approaches to studying in higher education Portuguese students: a Portuguese version of the approaches and study skills inventory for students     

Sandra Cristina A. T. S. Valadas  Fernando R. Gonçalves  Luís M. Faísca 《Higher Education》2010,59(3):259-275

This paper examines the validity of the Approaches and Study Skills Inventory for Students—short version (ASSIST; Tait et al. in Improving student learning: Improving students as learners, 1998), to be used with Portuguese undergraduate students. The ASSIST was administrated to 566 students, in order to analyse a Portuguese version of this inventory. Exploratory factor analysis (principal axis factor analysis followed by direct oblimin rotation) reproduced the three main factors that correspond to the original dimensions of the inventory (deep, surface apathetic and strategic approaches to learning). The results are consistent with the background theory on approaches to learning. Additionally, the reliability analysis revealed acceptable internal consistency indexes for the main scales and subscales. This inventory might represent a valuable research tool for the assessment of approaches to learning among Portuguese higher education students.  相似文献