1,256 research outputs found
Towards a new curriculum design: The role of the process variables and their alteration
A comienzos de los ochenta toda una línea de investigación se pone en marcha con una idea central: romper el tradicional abismo existente entre teoría pedagógica y praxis escolar. Los estudios del Mesa Seminar de Chicago de 1980 con Bloom a la cabeza abanderan esta dirección que encuentra terreno abonado en realizaciones paralelas tales como la investigación-acción o el interés por la evaluación procesual-cualitativa. Se toma conciencia de que existen variables curriculares -repetidamente constatadas, definidas y estudiadas que son inamovibles por la escuela, tal es el caso del nivel de ingresos de los padres. Al mismo tiempo se reconoce que existen variables de proceso que pueden y deben ser alteradas, con objeto de optimizar el proceso de enseñanza-aprendizaje. Este trabajo se inscribe en esa línea voluntarista de acercamiento entre teoría educativa y praxis escolar, de intervención sobre esas variables archiconstatadas a lo largo de las tres últimas décadas.At the beginning of the eighties a line of research was initiated whit one central idea; to break the traditional abysm between pedagogical theory and classroom practice. The studies of the Chicago Seminar of 1980 with Bloom at the head, marked out this direction which found fertile soil in parallel activities such as action research or the interest in process-qualitative evaluation. It was realized that there exist curriculum variables-repeatedly confirmed, defined and studied-which are immovable for the school, as for example the income level of the parents. At the same time it was recognized that there exist process variables which can and agility to be alert whit the aim of getting the best oút of the teaching/learning process. This work follows the line of drawing together educational theory and school practice, of intervention over these variables constantly confirmed throughout the last three decades.peerReviewe
Poly-Harmonic Distortion Model Extraction in Charge-Controlled One-Port Devices
A charge-controlled, one-port device is used to
describe and discuss the extraction procedure of a Poly-Harmonic Distortion (PHD) model in detail. For this case, both voltage and current waveforms are shown to be enough to fully characterize the PHD model. It is also shown that all the information
specifically required for this PHD model definition can be stored in the Fourier coefficients of the incremental conductance and capacitance. The results are validated by comparing them with those obtained using a commercial circuit simulation tool.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Programas de desarrollo dirigidos a agricultoras : identificando clústeres para el caso del programa "Formación y capacitación para mujeres campesinas" de Chile
This article aims to contribute to the evaluation of development policies for female
farmers based on their beneficiaries attitudes. For this, it was conducted a survey in
the Metropolitan Region of Santiago, Chile, to a representative sample of participants in
the "Education and training program for rural women" of the Chilean National Institute
for Agricultural Development. The questionnaire applied was divided into the following
sections: i) personal characteristics of the farmers and their family unit; ii) technical,
productive and commercial features; iii) farm and household income; and iv) vision
of themselves and program-related attitudes. The data collected was processed by
descriptive and multivariate techniques such as principal components and cluster
analysis. The results show a positive assessment of the program on an aggregate level,
although there are significant dissimilarities within the sample, allowing three clusters
to be identified: "reticent participants" (42.3%), "associative participants" (20.5%) and
"empowered participants" (37.2%). The farmers on those clusters present differences
not only in their attitudes towards the program but also in their education level, income,
farm profitability and balance between productive and domestic roles. Its concluded
that individual characteristics and circumstances impact beneficiaries perception of the
programs, which should be considered in their design and implementation.Este artículo tiene como propósito contribuir a la evaluación de las políticas de
desarrollo dirigidas a mujeres campesinas, considerando en este sentido las actitudes
de sus propias beneficiarias. Para ello, se aplicó una encuesta en la Región Metropolitana
de Santiago, Chile, a una muestra representativa de participantes del programa
"Formación y Capacitación para mujeres campesinas" del Instituto Nacional de
Desarrollo Agropecuario. El cuestionario utilizado se dividió en las siguientes secciones:
i) características personales de las productoras y de sus unidades familiares; ii) rasgos
técnicos, productivos y comerciales; iii) ingreso predial y familiar; y iv) visión respecto
de ellas mismas; así como actitudes frente al programa. La información levantada se
procesó mediante técnicas descriptivas y multivariantes, como componentes principales
y análisis de conglomerados. Los resultados obtenidos muestran una valoración
positiva del programa a nivel agregado, sin embargo con diferencias significativas entre
las encuestadas, permitiendo identificar tres grupos: "participantes reticentes" (42,3%),
"participantes asociativas" (20,5%) y "participantes empoderadas" (37,2%). Las
agricultoras en cada grupo divergen no solo en sus actitudes respecto del programa, sino
también en su nivel educacional, ingreso, rentabilidad de sus negocios y relación entre
los roles productivo y doméstico. Se concluye que las características y circunstancias
individuales impactan en la percepción que las beneficiarias tienen sobre los programas,
lo que debe ser considerado en su diseño y ejecución.Fil: Boza, Sofía.
Universidad de Chile. Facultad de Ciencias Agronómicas.Fil: Muñoz, Tomás.
Universidad de Chile. Facultad de Ciencias Agronómicas.Fil: Rico, Margarita.
Universidad de Valladolid (España)Fil: Muñoz, Jazmín.
Universidad de Chile. Facultad de Ciencias Agronómicas
Methanol dehydration on carbon-based acid catalysts
Methanol dehydration to produce dimethyl ether (DME) is an interesting process for the chemical industry since DME is an important intermediate and a promising clean alternative fuel for diesel engines. Pure or modified γ-aluminas (γ-Al2O3) and zeolites are often used as catalysts for this reaction. However, these materials usually yield non desirable hydrocarbons and undergo fast deactivation.
In this work, we study the catalytic conversion of methanol over an acid carbon catalyst obtained by chemical activation of olive stone with H3PO4. A significant amount of phosphorus remains over the catalyst surface after the activation process, mostly in form of C-O-PO3 and C-PO3 groups, which provide the carbon a relatively high surface acidity and oxidation resistance. Methanol decomposition on this catalyst yields selectivities to DME higher than 82% at 623K and methanol conversion of 34%, under the operating conditions studied.
The activated carbon catalytic activity and stability, under inert and oxidant atmospheres, as well as different regeneration procedures, were studied. In the absence of oxygen, the catalyst suffers a progressive deactivation by coke deposition on the active acid sites (Fig. 1). The presence of oxygen modifies the carbon surface chemistry, probably through oxygen spillover on the catalyst surface, where the availability of labile oxygen avoids catalyst deactivation. A reaction mechanism has been proposed where methanol dehydration seems to proceed through an Eley-Rideal mechanism, which assumes the adsorption of water and oxygen spillover on the acid active sites, avoiding coke deposition
Perfomance analysis of hybrid systems based on externally heayed closed-cycle engines
This work presents a comparative analysis of hybrid
systems that make use of closed-cycle externally heated
bottoming systems. Two options are considered:
reciprocating (Stirling) engines and supercritical carbon
dioxide turbines. These engines share the common
feature of working on closed cycles with optimised fluids
(H2 and CO2 respectively). However, they differ in their
internal structure: Stirling engines make use of volumetric
machinery whereas the SCO2 system is composed by
turbomachinery. In both cases, the working fluid is
subjected to very high pressure and temperature in the
range of 50-200 bar and 40-650 ºC.
A brief description of both bottoming systems is
provided in the article along with the expected
performance of each case in on-design and off-design
(part load) conditions. The analysis is therefore split into
two stages. First, a comparison is shown for on-design
operation aiming to evaluate the maximum efficiency
attainable by the proposed systems. Second, a
preliminary analysis of off-design operation is presented.
The paper concludes that hybrid systems based on
atmospheric fuel cells and externally heated closed-cycle
bottoming engines have the potential to outperform
conventional pressurised fuel cells and gas turbines
hybrids while preserving the topping system from the
demanding operating conditions of the latter configuratio
Producción del disco CZ de El Corrientazo
Grabación, edición y mezcla en estudio de un producto fonográfico. Realizar la producción del primer disco compacto, descarga virtual o vinilo del grupo musical al cual pertenezco: El CorrientaZo.Maestro (a) en MúsicaPregrad
Usabilidad en dashboards para analítica de Big Data
A día de hoy, una de las mayores industrias en el mundo del entretenimiento es la de los videojuegos. Actualmente, existen multitud de tipos de videojuegos entre los que se encuentran los “juegos serios”. Estos tienen como principal objetivo la educación, cuyo propósito es desafiar y generar metas a los jugadores. De la interacción entre los usuarios y los juegos serios, se genera información que se puede convertir en relevante y útil gracias a la analítica de aprendizaje.
El presente trabajo fin de grado (a partir de ahora TFG) tiene como objetivo facilitar la creación de nuevas visualizaciones, que ayuden a interpretar los datos y que se integren dentro de una infraestructura de analítica de aprendizaje para su uso en juegos serios.
En este TFG se ha creado una estructura de un plugin de visualización para Kibana, utilizando librerías de visualización externas que facilitan su creación. Para facilitar al máximo la creación de esta estructura, se ha programado un generador de proyectos. Para comprobar el funcionamiento de toda esta estructura, se realizan varios ejemplos utilizando el generador de plugins, donde se incorporan visualizaciones creadas por el autor de este TFG
Contributo para um modelo de estimativa rápida de custos em propostas de engenharia - um caso da indústria da refrigeração
Esta dissertação nasce da oportunidade de aproximar o contexto empresarial ao contexto
académico, desenvolvendo-se um estudo sobre os custos envolvidos em diversas
obras, com vista a melhorar propostas de engenharia na indústria da refrigeração.
O trabalho de orçamentação é um processo onde são envolvidos bastantes recursos,
quer pessoais quer temporais. Um factor bastante relevante para a sua realização é a sua
complexidade técnica, podendo demorar entre uma a duas semanas até à sua conclusão.
Deste modo, esta dissertação focou-se em desenvolver uma metodologia onde é possível
estimar o custo total de uma obra, a fim de reduzir a utilização destes recursos e a valorizálos.
Nesta dissertação apresentam-se vários estudos com base nos custos analisados, onde
é feito:
• Uma análise do diferencial de custos globais nas obras analisadas;
• Uma análise do diferencial de custos parciais nas obras analisadas;
• Uma análise de quais as parcelas de uma obra que mais contribuem para o diferencial
global de uma obra;
• Um estudo de como é a constituição de uma obra, com base nos custos reais.
Consequentemente obteve-se uma equação que permite estimar o custo total de uma
obra, onde são utilizadas variáveis que ajudam a definir as características da mesma.
Com base neste modelo é possível quantificar uma estimativa do custo para um orçamento
em uma a duas horas.This thesis stems from the opportunity of bringing the corporate and academic contexts
together, developing a study on the costs involved in several construction works
with the objective of improving engineering proposals in the refrigeration industry.
The process of budgeting involves several resources, both in terms of manpower and
time. A deciding factor for their execution is their technical complexity, reaching one
to two weeks until their conclusion. In this manner, this thesis focused on developing a
methodology that enables the estimation of the total cost of a construction work, with the
objective of reducing resource utilization and maximizing their usage.
In this thesis, several studies based on the analyzed costs are presented, where the
following are made:
• Differential global cost analysis in the studied construction works;
• Differential global cost analysis in the studied construction works;
• An analysis of which parcels of a construction work most contribute to its global
differential;
• A study of the constitution of a construction work based on its real costs.
As a result, an equation that allows the estimation of the total cost of a construction
work was obtained, where several variables are used that allow the definition of its
characteristics.
Based on this model, it is possible to quantify a cost estimation for a budget in one to
two hours
Automorphisms of moduli spaces of vector bundles over a curve
Let X be an irreducible smooth complex projective curve of genus g at least
4. Let M(r,\Lambda) be the moduli space of stable vector bundles over X or rank
r and fixed determinant \Lambda, of degree d. We give a new proof of the fact
that the automorphism group of M(r,\Lambda) is generated by automorphisms of
the curve X, tensorization with suitable line bundles, and, if r divides 2d,
also dualization of vector bundles.Comment: 12 page
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