Universitat Politècnica de Catalunya
Mostrando ítems 1-20 de 26
In the middle of the 70s, some authors suggested that accretion of hydrogen and helium rich material by a neutron star in a binary system, where the companion star would have low mass, could explain thermonuclear bursts ...
Este trabajo está dividido en dos partes claramente diferenciadas, ambas dentro de la Física no lineal.<br/>La primera es un estudio de las inestabilidades de la corriente en semiconductores extrinsecos, incluyendo ...
Two-phase flows are encountered in a wide range of applications both on-ground and in space. The dynamics of such flows in the absence of gravity is completely different from that in normal gravity due to the absence of ...
This Thesis is devoted to the construction of global climate networks (CNs) built from time series -surface air temperature anomalies (SAT)- using nonlinear analysis. Several information theory measures have been used ...
En la tesis doctoral Convección térmica en un anillo cilíndrico en rotación se estudian diferentes aspectos de la dinámica lineal y no lineal de un fluido Boussinesqconfinado en un anillo cilíndrico, en rotación alrededor ...
La presente tesis es un estudio mediante simulaciones de dinámica molecular de los efectos de la polarización inducida en las propiedades de las sales fundidas, en concreto de los haluros de plata. Estas sales se caracterizan ...
In this thesis we have focused on semi-classical methods that enables us to obtain non-thermal spectra for the vast majority of black holes. This fact is due to taking into account the backreaction of the metric, when the ...
Shoreline sand waves are shoreline undulations with a length scale of several kilometres and a time scale of years to decades. They occur on many coasts, migrating in the direction of the dominant littoral drift and they ...
En esta tesis se estudia la formación y mantenimiento de los bancos de arena sobre la plataforma continental asociados a la costa. Estos son estructuras sedimentarias de forma alargada y que se repiten periódicamente a lo ...
Even though the transition to turbulence has been studied for over a century, its complete comprehension still remains unclear even for the simplest flows and continues to be a daunting challenge for the scientific community. ...
In the field of second harmonic (SH) generation most studies have been concerned with maximizing conversion efficiencies, generally achievable at the phase matching (PM) condition. Outside of the PM the conversion efficiency ...
Esta tesis se dedica en un estudio de estabilidad no lineal de la morfodinàmica de la zona de rompientes de playas de arena. El modelo numérico MORFO55 resuelve las ecuaciones de aguas someras no lineales para la hidrodinámica ...
Despite the large amount of research which has been conducted on turbulent flows, a full understanding of their dynamics as well as the mechanisms involved in the onset of turbulence is still missing. Experimental studies ...
Several microscopic theories point out that Bose-Einstein condensation (BEC), i.e., a macroscopic occupation of the lowest energy single particle state in many-boson systems, may appear also in quantum fluids and solids ...
L'estudi de la formació de microstructures en processos de solidificació té importants aplicacions científiques i tecnològiques. L'aparició d'aquestes estructures determina les propietats elèctriques i mecàniques del ...
Esta tesis describe el diseño, la fabricación y la caracterización óptica de sistemas plasmónicos resonantes capaces de confinar y aumentar campos de luz en la escala manométrica. En primer lugar, se utilizaron modelos ...
Els materials nanoestructats periòdics han ofert, en les dues darreres dècades, un nou marc per a l'estudi de la interacció entre la radiació electromagnètica i la matèria. Aquestes estructures permeten modelar les propietats ...
The study of the elastic, dielectric and piezoelectric non-linear behavior in PZT-based and KNN-based piezoelectric ceramics represent the main goal of this work. Both systems present a perovskite-like structure. Several ...
La luz comprimida (squeezed light) es uno de los componentes importantes de los experimentos de memorias cuánticas. Un almacenamiento eficiente<br/>de la luz comprimida en una colectividad de átomos exige que la luz ...
Neutron diffraction is a powerful technique that allows to probe the structure of disordered phases across a variety of length scales. However, due to the inherent complexity of these disordered hases, the analysis of the ...
