Sliding mode filtering for stochastic systems with polynomial state and observation equations     

Michael Basin  Pablo Rodriguez-Ramirez 《Journal of The Franklin Institute》2014

In this paper, the mean-square and mean-module filtering problems for polynomial system states over polynomial observations are studied proceeding from the general expression for the stochastic Ito differentials of the estimate and the error variance. The paper deals with the general case of nonlinear polynomial states and observations. As a result, the Ito differentials for the estimates and error variances corresponding to the stated filtering problems are first derived. The procedure for obtaining an approximate closed-form finite-dimensional system of the sliding mode filtering equations for any polynomial state over observations with any polynomial drift is then established. In the examples, the obtained sliding mode filters are applied to solve the third-order sensor filtering problems for a quadratic state, assuming a conditionally Gaussian initial condition for the extended second-order state vector. The simulation results show that the designed sliding mode filters yield reliable and rapidly converging estimates.  相似文献   

Sliding mode state and parameter identification for linear stochastic systems     

Michael Basin  Pablo Rodriguez-Ramirez 《Journal of The Franklin Institute》2014

This paper presents the sliding mode mean-square and mean-module state filtering and parameter identification problems for linear stochastic systems with unknown parameters over linear observations, where unknown parameters are considered Wiener processes. The original problems are reduced to the sliding mode mean-square and mean-module filtering problems for an extended state vector that incorporates parameters as additional states. The obtained sliding mode filters for the extended state vector also serve as the optimal identifiers for the unknown parameters. Performance of the designed sliding mode mean-square and mean-module state filters and parameter identifiers are verified for both, stable and unstable, linear uncertain systems.  相似文献   

Critical analysis of the effects of the digital technologies on reading and learning / Análisis crítico sobre los efectos de las tecnologías digitales en la lectura y el aprendizaje     

Ladislao Salmerón  Pablo Delgado 《Cultura y Educación》2013,25(3):465-480

Abstract

In the digital age, the introduction of digital technologies (or information and communication technologies, ICT) in classrooms is a necessary, imperative reality. However, the educational results do not seem to match the expectations generated. For this reason, this revision seeks to make up for the scant attention paid to the possible harmful effects of the use of ICT based on research and educational practice. After providing a general overview of the impact of ICT on learning, we survey the results of studies that reveal potential negative consequences of their use inside and outside the school context. We analyse their impact on both academic performance and other more specific areas, such as reading comprehension, and we stress the negative effects on so-called ‘digital natives’. In short, what stands out is the importance of an evidence-based education practice which bears in mind the possible harmful effects of using ICT and bears in mind that its beneficial effects seem to rely on not only how much but also how they are used.  相似文献   

Una aportación española al programa de la psicología histórico-cultural del desarrollo y la educación     

Amelia Alvarez  Pablo del Río 《Infancia y Aprendizaje》2013,36(51-52):5-14

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Publicidad y consumo: hacia un modelo educativo     

Pablo del Río 《Infancia y Aprendizaje》2013,36(35-36):139-173

Resumen

Se analizan las relaciones entre información y formación al consumidor y las implicaciones psicológicas y educativas en uno y otro caso, prestando especial atención a tres diferentes competencias aspectos: (estrategias de procesamiento de la información, capacidad de memoria y habilidades para la resolución de problemas); los factores evolutivo-contextuales (influencia y diseño de los contextos de consumo) y direccionalidad de la conducta: (autonomía, normatividad y estructuración de las actividades del niño como consumidor).

De cara al diseno de políticas sociales y programas educativos se analizan: los procesos de consumo familiar y la educación del niño consumidor en el contexto familiar, el consumo como contenido explícito e implícito en el curriculum escolar y alternativas de programación, y el papel educativo de los medios de comunicación de masas en este campo.  相似文献   

Investigación y práctica educativa en el desarrollo de la comprensión lectora     

Pablo del Río 《Infancia y Aprendizaje》2013,36(31-32):21-43

Resumen

Se revisan en este artículo los procesos de adquisición y uso del lenguaje y la lectoescritura en la escuela, como conformadores de los diversos mecanismos de comprensión. Se valora a continuación la aportación de los modelos teóricos de instrucción en la comprensión: esquemas, estrategias de resumen y extracción de ideas principales, técnicas de estudio y mecanismos metacognitivos de control, con vistas a una renovación de la didáctica de la lectoescritura.  相似文献   

Toma el Tiempo: The Wisdom of Migrant Families in Consultation     

Mary M. Clare  Anna Jimenez  Jennifer McClendon 《Journal of educational and psychological consultation》2013,23(1-2):95-111

Children of migrant farm working families often live and learn in conditions that conspire against both health and education. At the same time, these children are as capable as any in our nation. Education and health care professionals are frequently in positions to support these capabilities and migrant families can be significant contributors to the success of education and health programs. However, the variables obstructing collaboration with migrant families are numerous and often go unidentified. More invisible are the variables supporting natural and positive inclusion of these families in problem-solving processes. This article reveals both barriers and avenues to connecting with migrant farm working families so their children may gain greater benefits from health and educational services.  相似文献   

Actividad y lenguaje. El diseño cultural como marco para un programa de enseñanza del inglés como lengua extranjera     

Amelia Alvarez  Pablo del Río 《Cultura y Educación》2013,25(7-8):99-125

La enseñanza de una lengua extranjera en el medio escolar se conceptualiza en este artículo desde una perspectiva histórico-cultural, planteando la necesidad de recurrir al diseño cultural de entornos y actividades en la LE a partir de las peculiaridades del entorno social de los niños y del centro escolar. El diseño cultural del proceso de enseñanza-aprendizaje propone vertebrar la programación en torno a ejes de subsistemas de actividades rectoras procedentes de la cultura que permitan al niño acceder a la lengua extranjera como un sistema global de sentidos y significados.  相似文献   

Functional hamstrings: quadriceps ratios in elite women's soccer players     

Nathaniel D.M. Jenkins  Matthew J. Hawkey  Pablo B. Costa  Ryan E. Fiddler  Brennan J. Thompson  Eric D. Ryan 《Journal of sports sciences》2013,31(6):612-617

Abstract

We compared starters and non-starters for various isokinetic strength variables in elite women’s soccer players. A convenience sample of 10 starters (mean ± s; age = 20 ± 2 years; height = 170 ± 4 cm; body mass = 65 ± 5 kg) and 7 non-starters (age = 20 ± 1 years; height = 164 ± 3 cm; body mass = 63 ± 4 kg) performed maximal voluntary muscle actions of the leg extensors (concentric) and flexors (eccentric) on an isokinetic dynamometer in order to measure concentric peak torque for the leg extensors, eccentric peak torque for the leg flexors, and the functional hamstrings:quadriceps (H:Q) ratio at 1.047 rad · s^-1 and 4.189 rad · s^-1 concentric peak torque for the leg extensors was not different between starters and non-starters. However, it was greater at 1.047 rad · s^-1 than at 4.189 rad · s^-1 in both groups. Eccentric peak torque for the leg flexors was greater for the starters versus non-starters at 4.189 rad · s^-1. Eccentric strength of the leg flexors at fast movement velocities may be used as an effective physiological profile and may discriminate between playing status in elite women’s soccer players.  相似文献   

Comparing Disaster News on Twitter and Television: an Intermedia Agenda Setting Perspective     

Sebastián Valenzuela  Soledad Puente  Pablo M. Flores 《广播与电子媒介杂志》2017,61(4):615-637

Intermedia agenda setting predicts a high degree of convergence between news media agendas. However, the rise of social media forces a re-examination of this expectation. Using the 8.8-earthquake of February 27, 2010 in Chile as a case study, this article compares which topics were covered by professional journalists on broadcast news and Twitter, analyzing both cross-sectional and longitudinal trends. A positive, reinforcing influence was found among the journalistic agendas of TV and Twitter. However, counter to the idea that social media are echo chambers of traditional media, it was found that Twitter influences TV news more so than the other way around. Thus, the study provides an early lens into the agenda setting function of social media among television news professionals, and its findings are consistent with Twitter succeeding among journalists due to its provision of valuable information.  相似文献