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61.
In this work a procedure for obtaining polytopic λ-contractive sets for Takagi–Sugeno fuzzy systems is presented, adapting well-known algorithms from literature on discrete-time linear difference inclusions (LDI) to multi-dimensional summations. As a complexity parameter increases, these sets tend to the maximal invariant set of the system when no information on the shape of the membership functions is available. λ-contractive sets are naturally associated to level sets of polyhedral Lyapunov functions proving a decay-rate of λ. The paper proves that the proposed algorithm obtains better results than a class of Lyapunov methods for the same complexity degree: if such a Lyapunov function exists, the proposed algorithm converges in a finite number of steps and proves a larger λ-contractive set. 相似文献
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Emilio Santa Rita Jr. 《Community College Journal of Research & Practice》2013,37(5):519-529
The study was an investigation of the usefulness of 50 variables in predicting the academic performance of 86 students readmitted to Bronx Community College following academic suspension. The variables included scores on the City University of New York placement tests, the Maudsley Personality Inventory, and the Survey of Study Habits and Attitudes. Other variables included 8 educational history items, 20 biographical items, and students' opinions about the contribution of 12 factors to their previous academic failure. The criterion measure was the academic performance (pass or fail) in the re‐entry semester. The principal conclusions to be derived from this study are that, for the population of academic failures characterized by average high school achievement and average scholastic aptitude, specific academic skills are important, past academic record seems unimportant, and a general factor called incentive seems important in the attainment of passing grades upon readmission. 相似文献
63.
Alberto Ruiz-Ariza Alberto Grao-Cruces Nuno Eduardo Marques de Loureiro Emilio J. Martínez-López 《International review of sport and exercise psychology》2017,10(1):108-133
Background: The aim of this systematic review was to investigate the association of different components of physical fitness on cognitive performance (CP) and academic performance (AP) in adolescents, taking into account potential confounders. Method: Studies were identified in four databases (Pubmed, SportDiscus, Web of Science, and ProQuest) from January 2005 through to January 2015. A total of 21 articles met the inclusion criteria. Results: 8 studies showed association between physical fitness and CP, and 11 studies with AP. Cardiorespiratory fitness, speed-agility, motor coordination, and perceptual-motor skill are the highest measures associated with CP and AP. However, the findings on strength and flexibility are unclear. Finally, 62% of the 21 studies used confounders. The most controlled confounder were socioeconomic status, fatness, pubertal status, sex, and age. Conclusion: Fitness is associated with higher CP and AP. More research is needed in order to understand the causes of the differential effect of physical fitness components on CP and AP. 相似文献
64.
When dealing with complex conceptual systems, low-prior- knowledge learners develop fragmentary and incorrect understanding. To learn complex topics deeply, these learners have to (a) monitor understanding to detect flaws and (b) generate explanations to revise and repair the flaws. In this research we explored if the detection of a flaw in understanding does lead to the generation of a revising explanation or, alternatively, if there is some independence between the two processes. In two studies participants with low prior domain knowledge learned about plate tectonics from a multimedia presentation. In Study 1 participants in two conditions received support for detection and their performance was compared to that of participants in two control conditions, one receiving no support and another one receiving support for both detection and revision. Performance on retention, transfer, and distortions revealed that the conditions with support for detection were not different from that with no support. The condition with support for both detection and revision was significantly better than all others. In Study 2 participants thought aloud while studying from the presentation. Self-generated detections were not correlated with revising explanations or with performance on retention or transfer measures. Overall, the results indicate that the detection of flaws in understanding does not necessarily lead to the generation of explanations to repair the flaws, meaning that this latter process is very difficult to execute and calls for instructional support. 相似文献
65.
ResumenEl presente artículo tiene como objetivo analizar los procesos de codificación y almacenamiento en tareas que implican el sistema de la MCP. Con este fin, hemos utilizado material verbal y hemos manipulado el grado de similitud táctil y fonética de los estímulos para estudiar su efecto en la retención a corto plazo. Los resultados de los dos experimentos indican, por un lado, que los ciegos se sirven de formatos de naturaleza diferente (táctil-fonémica) para mantener la información a corto plazo y, por otro lado, que incrementan su capacidad de almacenamiento con la edad. 相似文献
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Abstract This article describes Project ASTER III (Active Science Teaching Encourages Reform), a science professional development program for early elementary teachers, which is based on the premise that people learn best by doing. Very few professional development programs focus on early childhood teacher development and how best to integrate informal science centers into teaching. In ASTER III, development teams—consisting of university scientists, science educators, K‐3 teachers, and educators from a hands‐on science museum—developed 5E lesson plans aligned with the Ohio Academic Content Standards and the National Science Education Standards in conjunction with the museum’s exhibits. This study explores the impact of the ASTER III model on teacher perceptions about the role and effect informal science museum visits have on subsequent teaching and student learning. 相似文献
68.
Enrique A. González-Velasco Emilio Sanvicente 《Journal of The Franklin Institute》1980,310(2):135-142
The analytic representation of band-pass signals, which is extremely useful in information transmission and radar, is usually obtained by first introducing the Hilbert transform of a signal. We consider this procedure artificial, and propose here to follow the opposite path, which leads, in a natural way, to a motivated definition of the Hilbert transform. The key to this procedure is to show how, as a simple application of the Fourier integral, every band-pass signal can be expressed as the real part of a low frequency signal which modulates an exponential. Such a representation, called the analytic signal, is then used to define the Hilbert transform in a natural manner. Finally, we show that the term analytic signal is motivated by the fact that this signal is the restriction to the real axis of a function defined and analytic (holomorphic) in the upper half of the complex plane. 相似文献
69.
Fernando Rodriguez Emilio Duran Juan P. Vargas Blas Torres Cosme Salas 《Learning & behavior》1994,22(4):409-420
Goldfish were trained to obtain food in a four-arm maze placed in a room with relevant spatial cues. Four experimental conditions were run: allocentric, egocentric, egocentric + allocentric, and control. Relative to controls, all groups were able to solve the different tasks with high accuracy after 1 week of training. Subsequent transfer tests revealed place and response strategies for allocentric and egocentric groups, respectively, and both types of strategies for the ego-allocentric group. Moreover, the allocentric group showed the capacity to choose the appropriate trajectory toward the goal, even from novel starting points, presumably by using the distal cues as a whole. The results suggest that, in addition to using egocentric strategies, goldfish are able to solve spatial tasks on the basis of allocentric frames of reference and to build complex spatial cognitive representations of their environment. 相似文献
70.
Google Scholar,Web of Science,and Scopus: A systematic comparison of citations in 252 subject categories 总被引：1，自引：0，他引：1
Alberto Martín-Martín Enrique Orduna-Malea Mike Thelwall Emilio Delgado López-Cózar 《Journal of Informetrics》2018,12(4):1160-1177
Despite citation counts from Google Scholar (GS), Web of Science (WoS), and Scopus being widely consulted by researchers and sometimes used in research evaluations, there is no recent or systematic evidence about the differences between them. In response, this paper investigates 2,448,055 citations to 2299 English-language highly-cited documents from 252 GS subject categories published in 2006, comparing GS, the WoS Core Collection, and Scopus. GS consistently found the largest percentage of citations across all areas (93%–96%), far ahead of Scopus (35%–77%) and WoS (27%–73%). GS found nearly all the WoS (95%) and Scopus (92%) citations. Most citations found only by GS were from non-journal sources (48%–65%), including theses, books, conference papers, and unpublished materials. Many were non-English (19%–38%), and they tended to be much less cited than citing sources that were also in Scopus or WoS. Despite the many unique GS citing sources, Spearman correlations between citation counts in GS and WoS or Scopus are high (0.78-0.99). They are lower in the Humanities, and lower between GS and WoS than between GS and Scopus. The results suggest that in all areas GS citation data is essentially a superset of WoS and Scopus, with substantial extra coverage. 相似文献