182 research outputs found
Quasinormal modes of the Schwarzchild black hole with a deficit solid angle and quintessence-like matter: Scalar and electromagnetic perturbations
We study the quasinormal modes (QNM) for scalar, and electromagnetic
perturbations in the Schwarzchild black hole with a deficit solid angle and
quintessence-like matter. Using the sixth--order WKB approximation and the
improved asymptotic iteration method (AIM) we can determine the dependence of
the quasinormal modes on the parameters of the black hole and the parameters on
the test fields. The values of the real part and imaginary parts of the
quasi--normal modes increase with the decrease of the values of the deficit
solid angle and density of quintessence-like matter. The quasinormal modes
gotten by these two methods are in good agreement. Using the finite difference
method, we obtain the time evolution profile of such perturbations in this
Black Hole
Effects of quintessence on scattering and absorption sections of black holes
Basing on the ideas used by Kiselev, we study three black holes surrounded by
quintessence and the effects of quintessence on the classical and semiclassical
scattering cross-sections. In contrast, the absorption section is studied with
the sinc approximation in the eikonal limit. For Schwarzschild,
Reissner-Nordstr\"{o}m and Bardeen black holes surrounded by quintessence, the
values critical of charges and the normalization factor are obtained. We also
described the horizons and the extremal condition of the black holes surrounded
by quintessence. By setting for the quintessence state parameter in two the
particular cases w=-2/3 and w=-1/2
Simulation of Axisymmetric Flows with Swirl in Vorticity- Stream Function Variables Using the Lattice Boltzmann Method
In the present work, a Lattice Boltzmann formulation in vorticity-stream function variables is proposed for axisymmetric flows with swirl. For this purpose, several source terms are proposed and implemented. Although containing velocity gradients, these sources are in the Lattice Boltzmann framework and fulfill the Euler and Navier-Stokes equations in their conservative form. The main characteristics of the proposed method are: First, the momentum equation is solved using a unified Lattice Boltzmann solver; second, the proposed sources are consistent with the nonviscous and viscous momentum equations; and third, the implemented method is second-order accurate in space. Numerical tests on the Taylor-Couette flow with finite aspect ratio of 3.8 and the lid-driven cylindrical cavity flow were carried out showing good agreement with numerical and experimental results found in the literature, evidencing the ability of the implemented method to solve axisymmetric flows with swirl. In the case of the lid-driven cylindrical cavity flow, the implemented method is able to correctly reproduce some qualitative characteristics of this flow such as the vortex breakdown close to the cavity axis at different Reynolds numbers and cavity aspect ratio
Aplicación nativa de aula global para iPad
Este proyecto consistirá en el análisis y diseño de una aplicación de Aula Global, la
plataforma docente de la Universidad Carlos III de Madrid, para dispositivos Apple iPad
(Air, Mini o normal), que deberá ser capaz de realizar las siguientes tareas o funciones:
Acceso a la aplicación empleando el mismo usuario y contraseña que en Aula
Global y realizando una validación en el servidor.
Acceso a los cursos en los que se encuentre matriculado el usuario. Además podrán
marcarse como favoritos para facilitar su acceso desde la sección de favoritos en la que se
incluirán todos los cursos previamente marcados por el usuario.
En cada curso se podrán visualizar todos los documentos, vídeos, audios, enlaces y
tareas incluidos en él. No habrá posibilidad de realizar las tareas del curso, mostrándose un
resumen con el estado de la tarea y su calificación (en el caso de estar ya corregida).
Los usuarios con permisos suficientes (principalmente profesores) serán capaces de
ocultar, renombrar o eliminar recursos de cada curso.
Se tendrá acceso a los próximos eventos del usuario en el cual se reflejan todas las
actividades que tenga anotadas en la plataforma. Estas actividades podrán ser añadidas al
calendario del dispositivo.
Una sección dará acceso a todos los foros en los que el usuario esté incluido,
pudiendo leer y comentar todos los posts que en ellos se encuentren. El usuario recibirá
notificaciones push cada vez que haya nuevos comentarios en todos aquellos temas a los
cuales esté suscrito.
Todas estas funciones serán realizadas gracias al conjunto de servicios web que
proporciona Moodle (plataforma en la cual está basada Aula Global), que permitirá que la
consistencia de datos entre el servidor y la aplicación sea perfecta e instantánea y cualquier
cambio realizado en la web se vea reflejado en la aplicación móvil y viceversa.This senior design project is about analyzing and designing a mobile app, based on any
kind of Apple iPad device, for Aula Global, the Universidad Carlos III de Madrid learning
platform. That app should have at least the following features:
Log into the app using the same user and password as Aula Global by performing
a validation with the server.
Access to user courses. There will be also a favorites section that will give the user
the chance to select courses and access to them easily.
All the documents, videos, audios, links and tasks included in a course will be
available in the app. However, it won’t be possible to complete the course tasks, showing
just a summary showing its status and score if it’s already corrected.
Some users with special permissions (mainly teachers) will be able to hide, rename
or remove resources from a course.
The user will have the chance to see his/her next events planned on the platform. It
will be possible to synchronize these events with the device calendar.
A section containing all the forums where the user is taking part, giving the chance
to read and reply to all the posts included in those forums. The user will receive a push
notification each time that a theme subscribed by the user is replied.
All these features will be accomplished thanks to the web services provided by Moodle
(the open source learning platform on which Aula Global is based), allowing a real
persistency between server and app data. In this way, each change done in the web tool
will be reflected in the app and vice versa.Ingeniería Técnica en Informática de Gestió
EL ESPACIO GEOGRAFICO Y LA PLANIFICACION ESPACIAL
El concepto de espacio, que hasta hace algunas décadas evocaba sólo unconcepto geométrico, complementado inmediatamente con términos como«euclidiano», «isotrópico» o «infinito», y que dependía sólo de la matemática; seaborda hoy desde diferentes puntos de vista y ramas del conocimiento hasta llegara ser «banal» como lo dice Francois Perroux. ¿Quién de nosotros, a lo largo denuestra vida académica no ha escuchado mencionar la palabra espacio, perodefinida como un Sustantivo? En estas condiciones se habla del espacio temporalde los historiadores, el espacio económico de los economistas, o el espacio socialtan de moda; y de nuestro espacio: el espacio geográfico
Diplomado de profundización CISCO (Diseño e implementación de soluciones integradas LAN / WAN).
La temática desarrollada en el transcurso de la carrera de ingeniería de sistemas , el diplomado de profundización en CISCO y la solución a los escenarios propuestos en la guía de actividades , me ayudo a fortalecerme al momento de realizar una instalación de dispositivos, configuración de una red local o empresarial , administrar las distintas redes que en el futuro se puedan presentar y aún más significativo la manera de atesorar cada uno de los problemas en redes pequeñas y empresariales como por ejemplo LAN y WAN, durante el desarrollo del trabajo en conjunto apoyado firmemente por profesionales y especialistas del área, con el fin de optimizar cada una de las destrezas adquiridas y de trabajar modo autónomo en el esquema de redes. Esta actividad logro afianzar mis conocimientos sobre protocolos de enrutamiento avanzados como IGRP, RIP, OSPF, se utilizó tanto el direccionamiento IPV4 e IPV6, con ellos se enfatizó en la seguridad. Una temática que es suma importancia la cual día a día es importante a momento del diseño de una red. El presente trabajo validad estas habilidades y nos da una visión más clara de lo que nos enfrentaremos, conjuntamente es la manera de evaluar nuestros conocimientos obtenidos durante el desarrollo de las unidades que forman el curso, así como la formación autónoma que el diplomado tiene como requerimiento.The theme developed in the course of the systems engineering career, the diploma of deepening in CISCO and the solution to the scenarios proposed in the activity guide, helped me to strengthen myself when performing a device installation, configuration of a network local or business, manage the different networks that may arise in the future and even more significant how to treasure each of the problems in small and business networks such as LAN and WAN, during the development of joint work strongly supported by professionals and specialists in the area, in order to optimize each of the acquired skills and work independently in the network scheme. This activity was able to strengthen my knowledge about advanced routing protocols such as IGRP, RIP, OSPF, IPV4 and IPV6 addressing was used, with them security was emphasized. A theme that is very important which day by day is important when designing a network. The present work validates these skills and gives us a clearer vision of what we will face, together it is the way to evaluate our knowledge obtained during the development of the units that form the course, as well as the autonomous training that the diploma has as a requirement
Estudio del estado del arte sobre la predicción de deserción universitaria usando machine learning
La deserción universitaria trae como principal
consecuencia el aumento del número de estudiantes con educación
superior incompleta. Por lo cual se ha implementado técnicas
predictivas que han ayudado a detectar patrones que sirven
para el estudio del tema. Existen varias técnicas utilizadas para
el análisis predictivo como: La Regresión Logística, El Análisis
Bayesiano, Árboles de Decisión, entre otras, que han logrado
ser de suma importancia al momento de arrojar resultados
favorables que ayuden a llevar un control estadístico sobre los
casos de estudiantes desertores. Es importante señalar que el
uso de técnicas predictivas como la minería de datos en donde
se pueda visualizar las razones por las que los estudiantes
desertan según los patrones expresados estadísticamente para
que las autoridades institucionales puedan tomar decisiones
basándose en esta información y disminuir la deserción de
los estudiantes universitarios. Este artículo recopila información
sobre los diferentes algoritmos de predicción utilizados en el tema
de la deserción universitaria y analiza los datos sobre técnicas,
algoritmos, datasets, usados para la predicción de la deserción
universitaria, con el objetivo de encontrar la técnica de mejor
rendimiento al momento de realizar el estudio mediante métricas
de evaluación como son el Accuracy, Recall y F-Score.The main consequence of university desertion is the
increase in the number of students with incomplete higher education.
Therefore, predictive techniques have been implemented
that have helped to detect patterns that are useful for the study
of the subject. There are several techniques used for predictive
analysis such as: Logistic Regression, Bayesian Analysis, Decision
Trees, among others, which have become extremely important
when it comes to yielding favorable results that help to keep
statistical control over student cases. deserters. It is important to
point out that the use of predictive techniques such as data mining
where it can be visualized the reasons why students drop out
according to patterns expressed statistically so that institutional
authorities can make decisions based on this information and
reduce the dropout rate of university students. This article
collects information on the different prediction algorithms used
in the subject of university dropout and analyzes the data
on techniques, algorithms, datasets, used for the prediction of
university dropout, with the aim of finding the technique with
the best performance at the moment. to carry out the study on
university desertion through evaluation metrics such as Accuracy,
Recall and F-Score
Scattering and absorption sections of Schwarzschild-anti de Sitter with quintessence
In this paper, we study the Schwarzschild-anti de Sitter black hole
surrounded by quintessence. The critical values of the cosmological constant
and the normalization factor are obtained. We described the event horizons and
the extremal condition of the black hole surrounded by quintessence. Also, the
effects of quintessence on the classical and semiclassical scattering
cross-sections have been estimated. The absorption section is studied with the
sinc approximation in the eikonal limit. This study considers the quintessence
state parameter in the particular cases and .Comment: arXiv admin note: substantial text overlap with arXiv:2103.0641
Geodesics of Hayward black hole surrounded by quintessence
Basing on the ideas used by Kiselev, we study the Hayward black hole
surrounded by quintessence. By setting for the quintessence state parameter at
the special case of , using the metric of the black hole
surrounded by quintessence and the definition of the effective potential, we
analyzed in detail the null geodesics for different energies. We also analyzed
the horizons of the Hayward black hole surrounded by quintessence as well as
the shadow of the black hole
Brane world corrections to scalar vacuum force in RSII-p
Vacuum force is an interesting low energy test for brane worlds due to its
dependence on field's modes and its role in submillimeter gravity experiments.
In this work we generalize a previous model example: the scalar field vacuum
force between two parallel plates lying in the brane of a Randall-Sundrum
scenario extended by compact dimensions (RSII-). Upon use of Green's
function technique, for the massless scalar field, the 4D force is obtained
from a zero mode while corrections turn out attractive and depend on the
separation between plates as . For the massive scalar field a
quasilocalized mode yields the 4D force with attractive corrections behaving
like . Corrections are negligible w.r.t. 4D force for
radius less than m. Although the case is not
physically viable due to the different behavior in regard to localization for
the massless scalar and electromagnetic fields it yields an useful comparison
between the dimensional regularization and Green's function techniques as we
describe in the discussion.Comment: 14 pages, v2: discussion clarified, reference adde
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