A structural property of the wavelet packet transform method to localise incoherency of a signal     

Manuel Schimmack  Paolo Mercorelli 《Journal of The Franklin Institute》2019,356(16):10123-10137

This paper proves a general structural property of the wavelet tree for a given seminorm in the context of the wavelet packet transform method. This structural property can be used in denoising algorithms of different applications to guarantee the optimality of novel search strategies. The property holds for any input signals using any orthogonal analysing wavelet families. The property holds for any norms, which results to be a convex function through the wavelet tree. Using a defined norms, seminorms or pseudonorms, this property can be used to detect incoherent parts of an input signal by using the minimal depth of the tree. In this sense the proposed denoising procedure works without thresholds for the localisation of different kinds of noise, as well as for a stop criterium for an optimal representation of the incoherency. The proof of this property is performed by mathematical induction and the demonstration is based on orthonormality with the help of the multiresolution framework aspects of the wavelets packet tree. The Theorem is independent of the definition of the adopted norm and of the incoherent part of an input signal. In this sense, the discovered property is a general one, which is related to any norm and any nature of the signal incoherence. It can be used in different applications, in which a minimum of a norm is required to be calculated through the wavelet tree.  相似文献   

A Longitudinal Study on Stability and Transitions Among Bullying Roles     

Izabela Zych  Maria M. Ttofi  Vicente J. Llorent  David P. Farrington  Denis Ribeaud  Manuel P. Eisner 《Child development》2020,91(2):527-545

Trajectories of stability and change in bullying roles were examined through a longitudinal prospective study of 916 school students followed up biannually from age 11 to 17. Perpetrators and victims had relatively stable trajectories with most of the children remaining in the same role over time or becoming uninvolved. Bully/victim was the most unstable role with frequent transitions to perpetrators or victims. Developmental change in bullying roles was found with a decrease in physical forms over time in bullies and victims but with persistently high perpetration and victimization in bully/victims. These findings open new horizons in research and practice related to bullying and can be useful for its early detection or design of targeted interventions.  相似文献   

Morphological priming effects on children’s spelling     

Joao Manuel Rosa  Terezinha Nunes 《Reading and writing》2008,21(8):763-781

Previous research has suggested that children in the early grades of primary school do not have much awareness of morphemes. In this study, a priming paradigm was used to try to detect early signs of morphological representation of stems through a spelling task presented to Portuguese children (N = 805; age range 6–9 years). Primes shared the stem with the targets and contained well-articulated, stressed vowels; the stems of the target words and pseudo-words contained non-stressed schwa vowels, which typically result in spelling difficulties. If priming proved effective, the well-articulated vowels in the prime should result in an improvement in the spelling of the schwa vowels. Primes were presented in two conditions: in only-oral or in oral-plus-written form. Effectiveness of priming was assessed by comparison with a no-priming condition. For both words and pseudowords, there was a significant interaction between priming effects and grade. No priming effects were detected in 6- and 7-year-old children; oral-plus-written priming produced higher rates of correct vowel spelling for 8- and 9-year-olds; only-oral priming was effective in improving the vowel spelling of 9-year-olds. Thus older children can use morphological information under priming conditions when the prime and the target are not phonologically transparent but there is no evidence to suggest that younger children do so.  相似文献   

The chimera of the competency-based approach to teaching mathematics: a study of carpentry purchases for home projects     

Diego-Mantecón  José Manuel  Haro  Elena  Blanco  Teresa F.  Romo-Vázquez  Avenilde 《Educational Studies in Mathematics》2021,107(2):339-357

Educational Studies in Mathematics - The competency-based approach conceives mathematics as a necessary tool for dealing with daily-life tasks. Many studies have focused on examining the low math...  相似文献   

How to Assess and Categorize Teachers’ Views of Science? Two Methodological Issues     

Bächtold  Manuel  Cross  David  Munier  Valérie 《Research in Science Education》2021,51(5):1423-1435

Research in Science Education - This paper addresses two methodological issues related to the assessment of teachers’ views of science. The first concerns the distinction between the...  相似文献   

The Use of Different Translation Devices to Analyze Knowledge-Building in a University Chemistry Classroom     

Barreto  Lucas Passos  Rodrigues  Adriana Araújo Dutra  de Oliveira  Giordanna Camilla Bié  de Almeida  Laila Thayanne Gomes  Felix  Matheus Augusto Campelo  Silva  Penha de Souza  Quadros  Ana Luiza  Macedo  Andrea Mara  Mortimer  Eduardo Fleury 《Research in Science Education》2021,51(1):135-152

Research in Science Education - This research draws on Legitimation Code Theory (LCT) to understand the epistemic dimension of the higher education classroom discourse of a professor who is well...  相似文献   

Adult education in Andalusia     

Manuel Gracia Navarro  Juan Carlos López Eisman 《Prospects》1985,15(3):399-406

  相似文献   

Mental attention in gifted and nongifted children     

Jose I. Navarro  Pedro Ramiro  Jose M. Lopez  Manuel Aguilar  Manuel Acosta  Juan Montero 《European Journal of Psychology of Education - EJPE》2006,21(4):401-411

The relationship between the construct of mental attention and “giftedness” is not well established. Gifted individuals could make effective use of their executive functions and this could be related to their mental attentional capacity. The dialectic constructivist model developed by Pascual-Leone introduced the concept of mental attention or “effort”, relating it to mental capacity. The aim of this study is to investigate whether the measurement of mental capacity (M-measurement) is differential for a group of children with high IQs. 110 students between 4 and 18 years old participated in this study. Some were Gifted (n=70) and others Non-Gifted (n=40). Wechsler-R Scale and the Figural Intersection Test were administered to all participants. An interesting pattern was found in the younger groups. The gifted scored higher than the non-gifted in the Figural Intersection Test and much higher than their theoretical M. The non-gifted scored quite close to their theoretical M (based on age). In the oldest group, the gifted again achieved higher scores, but now they scored at the theoretical level, and the non-gifted underperformed.  相似文献   

A Remote Sensing Class Exercise to Study the Effects of El Niño in South America     

Moxey  Lucas Eduardo 《Journal of Science Education and Technology》2002,11(4):325-332

Satellite remote sensing techniques can be used for conducting environmental change detection studies following a natural disaster. Modern computer technology and free access to global satellite imagery allows educators to introduce undergraduate students to the fields of remote sensing and encourage their scientific participation through a research assignment that also serves as an educational exercise. The undergraduate physical science laboratory manuals used in higher education that contain printed remote sensing material often fail to effectively achieve these goals. This class exercise utilizes digital satellite imagery for studying the floods that resulted in the Paraná River region in South America during El Niño 1997–98. In addition, it examines vegetation cover and spectral profiles from the study area in order to further understand and assess the changes that were caused by this recurrent climatic anomaly.  相似文献   

Learning contexts for young children in Chile: process quality assessment in preschool centres     

María Olivia Herrera  María Elena Mathiesen  José Manuel Merino  Isidora Recart 《International Journal of Early Years Education》2005,13(1):13-27

ITERS (Infant and Toddler Environment Rating Scale), ECERS (Early Childhood Environment Rating Scale) and SACERS (School Age Care Environment Rating Scale) are used to measure process quality. The psychometric characteristics of the three scales are established, and high reliability and adequate validity are observed. The global quality process for the classrooms under study is less than good; process quality based on the direct interaction of adults with children in the classroom is better when compared with quality related to the experiences that children have with learning materials, equipment and space. The associations between child development outcomes and childcare quality are examined. Vocabulary, social development and adaptive behaviour show a strong and positive association with ECERS. Hierarchical regression analyses show that preschool quality has a significant and persistent effect in the variation of child outcomes (5%). These effects are maintained three years later, when children are in primary school (8%).  相似文献