Search results for "modelos"
showing 10 items of 199 documents
Avances de investigación en educación matemática
2020
El fomento de la flexibilidad y adaptabilidad en resolución de problemas matemáticos favorece el desarrollo de la competencia matemática. En este estudio se describe y justifica el diseño de una secuencia de tareas de modelización que permite analizar la flexibilidad inter-tarea en los estudiantes. El objetivo central del estudio es analizar si los estudiantes son capaces de adaptar sus planes de resolución según aspectos relativos al contexto de la tarea, cambiando de estrategia de una tarea a otra, si estos aspectos varían. En el estudio han participado 110 estudiantes del grado de Maestro/a en Educación Primaria; los resultados permiten conocer en qué medida son flexibles los estudiantes…
Explicación teórica y compromisos ontológicos : un modelo estructuralista
2021
En este ensayo me propongo esbozar un modelo de «explicación teórica con compromisos ontológicos». No se pretende que tal modelo tenga aplicación al uso de 'explicación' en la vida cotidiana, y ni siquiera que sea aplicable a todos los contextos científicos, tan sólo que tiene una significación genuina en grandes porciones de las ciencias naturales, particularmente en la física, y más generalmente en aquellas disciplinas que han sido matematizadas más o menos sistemáticamente. Mi tesis general, que voy a tratar de articular en lo que sigue, es simplemente la siguiente: al menos en muchos contextos de la ciencia teórica, la explicación adopta la forma de la inserción de una estructura de dat…
Problems of the Polish labour market against the backgrounds of the EU countries after 2004
2011
The situation in the labour market in the contemporary world is the subject of continual surveys and analyses. Particular attention in those surveys is focused on unemployment continuing over long-time that occurs despite governments of the majority of countries undertaking continual efforts aiming at liquidating or at least limiting it. The main goal of the paper is to present the current problems of the labour market in Poland and other European Union countries that developed under the influence of the global economic crisis. An attempt at presenting the current situation and selected characteristics of the labour market in Poland developed under the influence of the conditions existing a…
Andante filología
2010
¿Es posible diseñar un programa formativo para enseñar ciencias por Indagación basada en Modelos en la formación inicial de maestros? Fundamentos, ex…
2014
Una de las principales cuestiones que nos planteamos al abordar la formación inicial de maestros se refiere a los aspectos que deberíamos abordar de manera que se cubran las necesidades formativas de los futuros maestros para enseñar ciencias. De la combinación de las conclusiones de la investigación didáctica sobre formación docente y del análisis e interpretación realizados del enfoque de enseñanza por Indagación basado en Modelos que adoptamos, identificamos una serie de requerimientos de la formación inicial para promover el desarrollo de este enfoque en el aula. Requerimientos que plasmamos en el diseño de una propuesta formativa, y cuya presencia analizamos cuando concretamos el progr…
A contra-esperanza
2007
Multiring images of thin accretion disk of a regular naked compact object
2022
We discuss the importance of multi-ring images in the optical appearance of a horizonless spherically symmetric compact object, when illuminated by an optically thin accretion disk. Such an object corresponds to a sub-case of an analytically tractable extension of the Kerr solution dubbed as the {\it eye of the storm} by Simpson and Visser in [JCAP \textbf{03} (2022) 011], which merits in removing curvature singularities via an asymptotically Minkowski core, while harbouring both a critical curve and an infinite potential barrier at the center for null geodesics. This multi-ring structure is induced by light rays winding several times around the object, and whose luminosity is significantly…
Minimum main sequence mass in quadratic Palatini f ( R ) gravity
2019
General relativity yields an analytical prediction of a minimum required mass of roughly ∼0.08-0.09 M for a star to stably burn sufficient hydrogen to fully compensate photospheric losses and, therefore, to belong to the main sequence. Those objects below this threshold (brown dwarfs) eventually cool down without any chance to stabilize their internal temperature. In this work we consider quadratic Palatini f(R) gravity and show that the corresponding Newtonian hydrostatic equilibrium equation contains a new term whose effect is to introduce a weakening/strengthening of the gravitational interaction inside astrophysical bodies. This fact modifies the general relativity prediction for this m…
Light ring images of double photon spheres in black hole and wormhole spacetimes
2022
The silhouette of a black hole having a critical curve (an unstable bound photon orbit) when illuminated by an optically thin accretion disk whose emission is confined to the equatorial plane shows a distinctive central brightness depression (the shadow) whose outer edge consists of a series of strongly lensed, self-similar rings superimposed with the disk's direct emission. While the size and shape of the critical curve depend only on the background geometry, the pattern of bright and dark regions (including the size and depth of the shadow itself) in the image is strongly influenced by the (astro)physics of the accretion disk. This aspect makes it difficult to extract clean and clear obse…
Structure and stability of traversable thin-shell wormholes in Palatini f(R) gravity
2020
We study the structure and stability of traversable wormholes built as (spherically symmetric) thin shells in the context of Palatini f(R) gravity. Using a suitable junction formalism for these theories we find that the effective number of degrees of freedom on the shell is reduced to a single one, which fixes the equation of state to be that of massless stress-energy fields, contrary to the general relativistic and metric f(R) cases. Another major difference is that the surface energy density threading the thin shell, needed in order to sustain the wormhole, can take any sign and may even vanish, depending on the desired features of the corresponding solutions. We illustrate our results by…