Characterising pre-service primary teachers’ discursive activity when defining

2021/FQM-226, Junta de Andalucía; PPIIV.4/2021/005, Universidad de Sevilla

El discurso de estudiantes para maestro cuando describen y definen cuerpos geométricos

Todos los autores son miembros del grupo de investigación FQM-226 de la Junta de Andalucía, España y han sido parcialmente financiados por una Ayuda del Plan Propio de Investigación de la Universidad de Sevilla.En este trabajo, nos planteamos avanzar en el estudio de la práctica matemática de definir de los estudiantes para maestro. Esta investigación ha sido realizada usando un marco teórico sociocultural: la teoría de la comognición (Sfard, 2008), que considera las matemáticas como un tipo particular de discurso, lo que lo convierte en el foco de estudio. El instrumento de investigación diseñado, que constaba de 9 preguntas abiertas sobre la descripción y definición de cuerpos geométricos, hizo posible acceder al discurso tanto hablado como escrito de estudiantes para maestro. El análisis de este discurso nos ha permitido identificar propiedades discursivas (narrativas, uso de palabras, mediadores visuales, rutinas y metarreglas) con el objetivo de localizar conflictos comognitivos que podrían conllevar un aprendizaje matemático de estos estudiantes al resolverse.In this work, we study the mathematical practice of defining among pre-service teachers. This research has been carried out using a sociocultural theoretical framework: the theory of commognition (Sfard, 2008), which considers mathematics as a particular type of discourse and thus the discourse becomes the focus of study. A research instrument was designed with 9 questions about the description and definition of geometric solids, which made it possible to access pre-service teachers' spoken and written discourse. The analysis of this discourse has allowed the identification of discursive properties (narratives, word use, visual mediators, routines and meta-rules) with the aim of inferring commognitive conflicts whose resolution could lead to mathematical learning

Characterising Pre-Service Primary School Teachers’ Discursive Activity when Defining

This paper studies how pre-service primary school teachers construct and selectmathematical definitions through the analysis of their discursive activity.Specifically, the theory of commognition (Sfard, 2008) is employed to determinewhether the existence of different meta-rules always leads to the existence of acommognitive conflict. Moreover, we study the reasons that give rise to thecommognitive conflicts found and whether they are resolved. To this end, westudied the discourse of 45 pre-service primary school teachers while theyanswered several questions on defining geometric solids. The data in this studyconsisted of audio recordings of their discussions and their written answers. In thispaper, three vignettes showing different meta-rules are presented. In the first,discussions regarding the characteristics of a definition promoted the appearanceof different meta-rules that existed in incommensurable discourses, which meantthe existence of a commognitive conflict. This conflict highlights the fact thatcertain pre-service teachers confuse the processes of describing and defining. Boththe second and third vignettes featured the appearance of two different meta-rules.However, in both cases, those meta-rules could coexist in the same discourse, andtherefore a commognitive conflict could not be inferred

Overview of recent TJ-II stellarator results

The main results obtained in the TJ-II stellarator in the last two years are reported. The most important topics investigated have been modelling and validation of impurity transport, validation of gyrokinetic simulations, turbulence characterisation, effect of magnetic configuration on transport, fuelling with pellet injection, fast particles and liquid metal plasma facing components. As regards impurity transport research, a number of working lines exploring several recently discovered effects have been developed: the effect of tangential drifts on stellarator neoclassical transport, the impurity flux driven by electric fields tangent to magnetic surfaces and attempts of experimental validation with Doppler reflectometry of the variation of the radial electric field on the flux surface. Concerning gyrokinetic simulations, two validation activities have been performed, the comparison with measurements of zonal flow relaxation in pellet-induced fast transients and the comparison with experimental poloidal variation of fluctuations amplitude. The impact of radial electric fields on turbulence spreading in the edge and scrape-off layer has been also experimentally characterized using a 2D Langmuir probe array. Another remarkable piece of work has been the investigation of the radial propagation of small temperature perturbations using transfer entropy. Research on the physics and modelling of plasma core fuelling with pellet and tracer-encapsulated solid-pellet injection has produced also relevant results. Neutral beam injection driven Alfvénic activity and its possible control by electron cyclotron current drive has been examined as well in TJ-II. Finally, recent results on alternative plasma facing components based on liquid metals are also presented.ISSN:0029-5515ISSN:1741-432