Search results for "Linea"
showing 10 items of 7724 documents
Impact of the terrestrial reference frame on the determination of the celestial reference frame.
2022
Currently three up-to-date Terrestrial Reference Frames (TRF) are available, the ITRF2014 from IGN, the DTRF2014 from DGFI-TUM, and JTRF2014 from JPL. All use the identical input data of space-geodetic station positions and Earth orientation parameters, but the concept of combining these data is fundamentally different. The IGN approach is based on the combination of technique solutions, while the DGFI is combining the normal equation systems. Both yield in reference epoch coordinates and velocities for a global set of stations. JPL uses a Kalman filter approach, realizing a TRF through weekly time series of geocentric coordinates. As the determination of the CRF is not independent of the T…
Juegos y gamificación en las aulas de música de educación primaria.
2020
espanolEn la ultima decada se refuerza la tendencia de buscar herramientas innovadoras y motivadoras que ayuden a optimizar el proceso de adquisicion de aprendizajes. En esta linea, tras analizar recientes publicaciones y busquedas en bases de datos, se senalan los juegos y la gamificacion como herramientas educativas de apogeo en la actualidad. Desde un paradigma positivista, la pretension del estudio es contrastar estos resultados con la realidad educativa en la que viven dichas estrategias dentro del aula de musica de educacion primaria, tomando como fuente de analisis las percepciones y experiencias de los docentes que estan en activo en l’Horta Oest de Valencia. Para ello, se valora cu…
Comparing Different approaches - Data mining, Geostatistic, and Deterministic pedology - to assess the Frequency of WRB reference soil groups in the …
2014
Estimating frequency of soil classes in map unit is always affected by some degree of uncertainty, especially at small scales, with a larger generalization. The aim of this study was to compare different possible approaches - data mining, geostatistic, deterministic pedology - to assess the frequency of WRB Reference Soil Groups (RSG) in the major Italian soil regions. In the soil map of Italy (Costantini et al., 2012), a list of the first five RSG was reported in each major 10 soil regions. The soil map was produced using the national soil geodatabase, which stored 22,015 analyzed and classified pedons, 1,413 soil typological unit (STU) and a set of auxiliary variables (lithology, land-use…
System identification via optimised wavelet-based neural networks
2003
Nonlinear system identification by means of wavelet-based neural networks (WBNNs) is presented. An iterative method is proposed, based on a way of combining genetic algorithms (GAs) and least-square techniques with the aim of avoiding redundancy in the representation of the function. GAs are used for optimal selection of the structure of the WBNN and the parameters of the transfer function of its neurones. Least-square techniques are used to update the weights of the net. The basic criterion of the method is the addition of a new neurone, at a generic step, to the already constructed WBNN so that no modification to the parameters of its neurones is required. Simulation experiments and compa…
Linguistic diversity and assessment in multilingual schools
2018
En un entorno en el que la diversidad lingüística es natural, la metodología de evaluación afronta nuevos retos. La equidad en el proceso evaluativo aconseja la consideración de aspectos relacionados con las características psicométricas de las pruebas, el desarrollo de la competencia lingüística, o el contexto sociolingüístico, a través de modelos explicativos sobre las variables contextuales de naturaleza lingüística que inciden en el rendimiento. Utilizando datos poblacionales de centros educativos de segundo curso de enseñanza secundaria obligatoria que ofertan más de un modelo lingüístico en la Comunidad Autónoma del País Vasco (N=45), este trabajo analiza las respuestas de 2783 estudi…
Refugees’ perception of their new life in Germany
2021
Since 2015, Germany has been hosting noticeable incoming flows of refugees and asylum seekers and despite the quality of life of refugees is expected to be improved in the aftermath of their arrival to Germany, refugees are still facing several problems of integration and economic deprivation. Using a sample of individuals from the first wave of the German IAB-BAMF-SOEP Survey of Refugees, we present some preliminary analyses on their life satisfaction (LS). A gamma glm was estimated to focus on the association among levels of LS and main socio-demographic characteristics as well as post-migration factors. Greater stability (both in the legal and personal sphere) in refugees’ lives is posit…
Complex dynamics, hidden attractors and continuous approximation of a fractional-order hyperchaotic PWC system
2018
In this paper, a continuous approximation to studying a class of PWC systems of fractionalorder is presented. Some known results of set-valued analysis and differential inclusions are utilized. The example of a hyperchaotic PWC system of fractional order is analyzed. It is found that without equilibria, the system has hidden attractors.
Ryhmä SO(3) ja sen lineaariset redusoitumattomat esitykset
2014
Ryhmät ovat yksinkertaisina mutta elegantteina algebrallisina rakenteina jo pitkään olleet keskeinen osa niin puhdasta kuin sovellettuakin matematiikkaa. Erityisesti ryhmät soveltuvat erilaisten symmetrioiden esittämiseen. Ryhmien esitysteoriassa voidaan ryhmien rakennetta koskevia ongelmia palauttaa lineaarialgebran ongelmiksi, jotka ovat hyvin ratkaistavissa. Tämä tapahtuu kuvaamalla ryhmä homomorfisesti lineaarikuvausten ryhmään. Osoittautuu myös mielenkiintoiseksi tutkia jo itsessään lineaarikuvauksista muodostuvien ryhmien epätriviaaleja lineaarisia esityksiä. Erityisen tarkastelun kohteena tutkielmassa on klassinen matriisiryhmä SO(3), joka siis koostuu avaruuden ℝ3 rotaatiokuva…
Stem cell populations in the heart and the role of Isl1 positive cells
2013
Cardiac progenitor cells are multipotent stem cells isolated from both embryonic and adult hearts in several species and are able to differentiate at least into smooth muscle cells, endothelial cells and cardiomyocytes. The embryonic origin of these cells has not yet been demonstrated, but it has been suggested that these cells may derive from the first and secondary heart fields and from the neural crest. In the last decade, two diffe-rent populations of cardiac progenitor or stem cells have been identified and isolated, i.e., the Islet1 positive (Isl1+) and c-Kit positive (c-Kit+)/Stem Cell Antigen-1 positive (Sca-1+) cells. Until 2012, these two populations have been considered two separ…
Preconceptualización con modelos neuronales lineal-no lineal en el sistema visual
2018
El presente trabajo trata los procesos de normalización en el sistema visual, desde la entrada sensorial en retina, núcleo geniculado lateral (NGL) hasta el área visual V1, con el fin de encontrar un invariante de escena que sea capaz de indentificarla. Entendiendo como procesos de normalización a las transformaciones de las señales sensoriales desde la retina hasta el cortex. Los tres primeros estados con etapas lineales y no lineales, normalizan la escena ajustando la luminancia, el brillo y el contraste. El cuarto estado transforma la señal y la mapea en el espacio, en frecuencia y en ángulo, según el modelo implementado por Martinez-Garcia et al., (2018). Su correlato neuronal correspon…