Search results for "Model"
showing 10 items of 24058 documents
Estudio de la radiación neta en zonas semiáridas utilizando modelos lineales y neuronales y la sinergia entre GERB y SEVIRI
2012
Las regiones áridas o semiáridas se caracterizan por una distribución irregular de los recursos hídricos, lo que muchas veces constituye una limitación para el desarrollo de una determinada región. La variabilidad hidrológica de estas regiones se debe a la mala distribución espacial y temporal de la lluvia, a la topografía heterogénea y a los cambios de origen antropogénicos que muchas veces conducen a procesos de degradación y de desertificación. Como en estas regiones la evapotranspiración explica una parte significativa de la pérdida de agua hacia la atmósfera, el estudio y modelización de la radiación neta en superficie (Rn), es de suma importancia, una vez que las estimaciones o medici…
Reemigrācijas naratīvi ziņu portālos “lsm.lv”, “delfi.lv” un “tvnet.lv” (2013. gada janvāris – 2017. gada aprīlis)
2017
Bakalaura darba "Reemigrācijas naratīvi ziņu portālos “lsm.lv”, “delfi.lv” un “tvnet.lv” (2013. gada janvāris – 2017. gada aprīlis)" mērķis ir noteikt, kādus naratīvus par reemigrāciju veido vadošie interneta ziņu portāli Latvijā un noskaidrot, vai šajos medijos tie ir atšķirīgi, atsevišķi analizējot sabiedriskajā un komercmedijos iekļautos naratīvus. Darba teorētiskā daļā skaidrota naratīva teorija un aprakstīts naraloģijas pielietojums ziņu žurnālistikas pētīšanā, aprakstīta arī tiešsaistes, sabiedriskā un komercmediju specifika. Metodoloģijas daļas ietvaru veido kvantitatīvās kontentanalīzes, naratīva analīzes un daļēji strukturētās intervijas metožu raksturojums. Savukārt emipīrisko daļ…
Crear y gestionar conocimiento en red: agentes y procesos implicados.
2013
El proposito de este articulo es delimitar las funciones y roles de los principales agentes y los procesos que intervienen en la creacion y gestion del conocimiento (CGC) en red desde una plataforma virtual. Recoge, al respecto, algunos de los resultados mas destacados que se derivan de la investigacion “Agentes y procesos en la gestion del conocimiento en red” (I+D+i). El proceso de investigacion seguido ha supuesto, fundamentalmente, la puesta en marcha de 5 redes de CGC desde una plataforma virtual (Moodle) sostenida en el debate como estrategia; tambien la realizacion de un trabajo de campo que considero un cuestionario de autodiagnostico para 15 directivos y especialistas en desarrollo…
Column Adsorption Studies for the Removal of Ammonium Using Na-Zeolite-Based Geopolymers
2022
The aim of this study was to examine the removal of ammonium ions from a synthetic model solution by using Na-zeolite-based geopolymers. Na-zeolite (=analcime) is a residue from mining industry. Three adsorbents were prepared from Na-zeolite using different production steps and metakaolin as a blending agent. These novel adsorbents were investigated in a fixed-bed column system where the effects of different flow rates with the initial ammonium concentration of 40 mg/L were studied. The Thomas, Bohart–Adams and Yoon–Nelson breakthrough curve models fitted well with the experimental data with a high R2 value. After adsorption experiments, adsorbents were regenerated using a mixture of 0.2 M …
Mobilités étudiantes et territoires universitaires :vers une uniformisation des pratiques ?
2005
Since French Society enters the so-called “Economy of knowledge”, migrations of young people, especially these concerning students, are of most interests. Despite the fact that it could help to understand University as a system and ways regions can evolve, the study of students' migrations was not yet done. A set of results highlights first the main role of French capital region. It shows also main changes in migrations of students following vocational training in University. At least, it reveals that architectures of students' migrations look like these of migrations of the whole French population.
Acoustic wave guides as infinite-dimensional dynamical systems
2015
We prove the unique solvability, passivity/conservativity and some regularity results of two mathematical models for acoustic wave propagation in curved, variable diameter tubular structures of finite length. The first of the models is the generalised Webster's model that includes dissipation and curvature of the 1D waveguide. The second model is the scattering passive, boundary controlled wave equation on 3D waveguides. The two models are treated in an unified fashion so that the results on the wave equation reduce to the corresponding results of approximating Webster's model at the limit of vanishing waveguide intersection.
Validation of a Shear Model for RC and Hybrid Beams with Two Different Inclinations of Transversal Reinforcement
2016
The validation of an analytical model recently proposed for evaluation of the shear capacity in Reinforced Concrete (RC) beams containing multiple inclination of transverse stirrups is presented. The model is a suitable extension of that currently proposed in Eurocode 2 for the evaluation of the shear resistance, and it is derived by means of the the variable-inclination stressfield theory based on Nielsen’s plastic approach. Experimental and numerical data available in the literature on Hybrid Steel-Trussed Concrete Beams (HSTCBs) are used for model validation and result discussion. Finally, also the comparison with a different analytical approach for the assessment of the shear resistance…
Editorial: On the Nature and Scope of Habits and Model-Free Control
2021
Time-Dependent Multiple Depot Vehicle Routing Problem on Megapolis Network under Wardrop's Traffic Flow Assignment
2018
In this work multiple depot vehicle routing problem is considered in case of variable travel times between nodes on a metropolis network. This variant of the classic multiple depot vehicle routing problem is motivated by the fact that in urban contexts variable traffic conditions play an essential role and can not be ignored in order to perform a realistic optimization. Time-travel matrices corresponding to each period of planning horizon were formed by solving the traffic assignment problem in conjunction with shortest path problem. Routing problem instances include from 20 to 100 customers randomly chosen from a road network of Saint-Petersburg. The results demonstrate that taking into ac…
El modelo de enseñanza por investigación y las relaciones C/T/S. Resultados de una experiencia llevada a cabo con alumnos de BUP y COU
1993
Motivar a los alumnos de BUP y COU para que investiguen a través de la enseñanza C/T/S. Motivate the students of BUP and COU to investigate through the teaching C/T/S.