Search results for " Retrieval"
showing 10 items of 1114 documents
Fiabilidad y evidencias de validez de un instrumento para la evaluación de la calidad de los mapas conceptuales
2017
Diversos autores han señalado el interés y la pertinencia de los mapas conceptuales como herramientas para el aprendizaje significativo. Sin embargo, la revisión de la literatura pone de manifiesto la escasez de propuestas dirigidas a la evaluación de los mapas con criterios objetivables y la complejidad de las existentes. El objetivo del presente estudio fue desarrollar un instrumento para la evaluación de los mapas conceptuales en formato rúbrica. De esta manera, se consigue que los alumnos posean una herramienta que permita, mediante indicadores precisos, la evaluación de la calidad tanto de sus ejecuciones como de las ejecuciones realizadas por otros. Se construyó una rúbrica que incluy…
Educación XX1 : revista de la Facultad de Educación
2019
Aprender a aprender es una de las competencias claves fijadas por la Comisión Europea (CE, 2005 y 2006) para los sistemas educativos de los países miembros. Las últimas investigaciones ponen de relieve la importancia de que los estudiantes universitarios aprendan a aprender, por lo que este estudio se ubica en la universidad. El objetivo es concretar un modelo teórico sobre dicha competencia que permita su operacionalización en los grados universitarios. Para ello se ha realizado una revisión de la literatura sobre el tema. Después de estudiar su fundamentación científica y la normativa reguladora, se analizaron múltiples modelos -especialmente provenientes de la literatura europea- y se pr…
Balanced Large Scale Knowledge Matching Using LSH Forest
2015
Evolving Knowledge Ecosystems were proposed recently to approach the Big Data challenge, following the hypothesis that knowledge evolves in a way similar to biological systems. Therefore, the inner working of the knowledge ecosystem can be spotted from natural evolution. An evolving knowledge ecosystem consists of Knowledge Organisms, which form a representation of the knowledge, and the environment in which they reside. The environment consists of contexts, which are composed of so-called knowledge tokens. These tokens are ontological fragments extracted from information tokens, in turn, which originate from the streams of information flowing into the ecosystem. In this article we investig…
Non-thermal pressure support in X-COP galaxy clusters
2018
Galaxy clusters are the endpoints of structure formation and are continuously growing through the merging and accretion of smaller structures. Numerical simulations predict that a fraction of their energy content is not yet thermalized, mainly in the form of kinetic motions (turbulence, bulk motions). Measuring the level of non-thermal pressure support is necessary to understand the processes leading to the virialization of the gas within the potential well of the main halo and to calibrate the biases in hydrostatic mass estimates. We present high-quality measurements of hydrostatic masses and intracluster gas fraction out to the virial radius for a sample of 12 nearby clusters with availab…
Taming big knowledge evolution
2016
Information and its derived knowledge are not static. Instead, information is changing over time and our understanding of it evolves with our ability and willingness to consume the information. When compared to humans, current computer systems seem very limited in their ability to really understand the meaning of things. On the other hand, they are very powerful when it comes down to performing exact computations. One aspect which sets humans apart from machines when trying to understand the world is that we will often make mistakes, forget information, or choose what to focus on. To put this in another perspective, it seems like humans can behave somehow more randomly and still outperform …
Phase retrieval for studying the structure of vitreous floaters simulated in a model eye
2021
We simulate vitreous floaters in a model eye and apply a phase retrieval algorithm to recover the structure of the vitreous floaters. The algorithm requires modulating the object under study by a r...
Embodied Meter Revisited : Entrainment, Musical Content, and Genre in Music-Induced Movement
2022
Previous research has shown that humans tend to embody musical meter at multiple beat levels during spontaneous dance. This work that been based on identifying typical periodic movement patterns, or eigenmovements, and has relied on time-domain analyses. The current study: 1) presents a novel method of using time-frequency analysis in conjunction with group-level tensor decomposition; 2) compares its results to time-domain analysis, and 3) investigates how the amplitude of eigenmovements depends on musical content and genre. Data comprised three-dimensional motion capture of 72 participants’ spontaneous dance movements to 16 stimuli including eight different genres. Each trial was subjected…
Directionlets: Anisotropic Multidirectional representation with separable filtering
2006
In spite of the success of the standard wavelet transform (WT) in image processing in recent years, the efficiency of its representation is limited by the spatial isotropy of its basis functions built in the horizontal and vertical directions. One-dimensional (1-D) discontinuities in images (edges and contours) that are very important elements in visual perception, intersect too many wavelet basis functions and lead to a nonsparse representation. To efficiently capture these anisotropic geometrical structures characterized by many more than the horizontal and vertical directions, a more complex multidirectional (M-DIR) and anisotropic transform is required. We present a new lattice-based pe…
Analyse multirésolution pour la recherche et l'indexation d'images par le contenu dans les bases de données images - Application à la base d'images p…
2005
Recent content-based image retrieval systems offer an interactive visual browsing of images databases. These methods perform a classification of images (offline) into a search tree for users browsing (online). This approach shows three main problems:1) The size of decriptor vector (n>100) makes distance computing sensitive to dimensionality curse,2) Having many different kinds of attributes into descriptor vector does not help classification,3) In general, classification does not take in consideration users' search context. In this work, we propose a method based on building hierarchical signatures having small increasing sizes, this allows to take users' search context into consideration. …
Typology and Representation of Alterations in Territorial Units: A Proposal
2018
Abstract This article proposes a typology of boundary changes in territorial units at two points in time. The different types of changes are organized in a hierarchy and represented homogeneously, independently of the number of territorial units involved and of the changes to them. Each alteration is described precisely and unambiguously, and it is codified to allow the information to be treated automatically. In addition to providing efficient storage of the information about these changes, a canonical representation facilitates the automatic detection of inconsistencies in the database. At the same time, the typology allows us to define backward and forward equivalence rules, which helps …