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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The interaction between modality and evaluation within the argumentative structure of different text classes

Aranda M., Tamara, Cisternas C., Perla, Yeh, Shu-Lien January 2006 (has links)
Informe de Seminario para optar al grado de Licenciado en Lengua y Literatura Inglesa / The purpose of this research work is to carry out a small-scale empirically based study of the interaction between modality and evaluation within argumentative discourse in different text types, namely newspaper editorials, film and book reviews, eulogies, and advertorials. This bipartite study requires that some relevant descriptive models of each of these components and structures should be examined in order that some of their major descriptive categories should constitute the foundational theoretical framework on which the empirical study should be based. A brief presentation of each of these fundamental notion is given below.
2

Subdifferential calculus in the framework of Epi-pointed variational analysis, integral functions, and applications

Pérez Aros, Pedro Antonio January 2018 (has links)
Tesis para optar al grado de Doctor en Ciencias de la Ingeniería, Mención Modelación Matemática / La investigación de esta tesis es presentada en seis capítulos, desde el Capítulo 2 al Capítulo 7. El capítulo 2 proporciona una demostración directa de una caracterización reciente de convexidad dada en el marco de los espacios de Banach en [J. Saint Raymond, J. Convexo no lineal Anal., 14 (2013), pp. 253-262]. Estos resultados también extienden esta caracterización a espacios localmente convexos bajo condiciones más débiles y se basa en la definición de una función epi-puntada. El Capítulo 3 proporciona una extensión del Teorema Br{\o}ndsted-Rockafellar, y algunas de sus importantes consecuencias, a las funciones convexas semicontinuas inferiores definidas en espacios localmente convexos. Este resulado es demostrado usando un nuevo enfoque basado en un principio variacional simple, que también permite recuperar los resultados clásicos de una manera natural. El Capítulo 4 continúa el estudio de la epi-puntadas no convexas, bajo una definición general de subdiferencial. Este trabajo proporciona una generalización del teorema del valor medio de Zagrodny. Posteriormente este resultado es aplicado a los problemas relacionados con la integración de subdiferenciales y caracterización de la convexidad en términos de la monotonicidad del subdiferencial. El Capítulo 5 proporciona una fórmula general para $\epsilon$-subdiferencial de una función integral convexa en términos de $\epsilon$-subdiferenciales de la funcion integrante. Bajo condiciones de calificación, esta fórmula recupera los resultados clásicos en la literatura. Además, este trabajo investiga caracterizaciones del subdiferencial en términos de selecciones medibles que convergen al punto de interés. El Capítulo 6 proporciona fórmulas secuenciales para subdiferenciales bornológicos de un funcional integral no convexo. También son presentadas fórmulas exactas para el subiferencial Limiting/Mordukhovich, el subdiferencial Geometrico de Ioffe y el subdiferencial de Clarke-Rockafellar. El Capítulo 7 proporciona fórmulas para el subdiferencial de funciones de probabilidad bajo distribuciones Gaussianas. En este trabajo la variables de decisión esta tomada en un espacio infinito dimensional. Estas fórmulas se basan en la descomposición esférico-radial de vectores aleatorios Gaussianos. / CONICYT-PCHA/doctorado Nacional / 2014-21140621 y CMM - Conicyt PIA AFB170001
3

Vector measure orthogonal sequences in spaces of square integrable functions

Jiménez Fernández, Eduardo 02 December 2011 (has links)
This doctoral thesis is devoted to the analysis of orthogonal sequences in subspaces of spaces L2(m) of square integrable functions with respect to a Banach space valued countably additive measure m. The motivation of our work is to generalize the geometric arguments that provide the classical approximation procedures in Hilbert spaces. The notion of orthogonality lies in the center of the Hilbert space theory, and it allows to develop the theory of convergence of sequences in these spaces. Almost everywhere convergence, norm convergence and weak convergence are nowadays well known topics in the Hilbert space function theory. The Banach function spaces L2(m) of a vector measure m represent a broad class of Banach lattices: each 2-convex order continuous Banach lattice with a weak unit can be represented (by means of an order isomorphism) as a space L2(m) for an adequate vector measure m. The integral structure that the vector measure integration provides in these spaces allows to generalize the orthogonality arguments of the Hilbert space theory, although the spaces L2(m) are far from being Hilbert spaces. The first chapter of this memoir is devoted to introduce some fundamental concepts on Banach function spaces, vector measure integration and other topics that will be necessary in the rest of the work. Some results on convergence of sequences in Banach function spaces and Banach spaces are explained, and the general framework is established. Some orthogonality arguments are already introduced, both for sequences in L2(m) and for the integrals of these sequences when the vector measure m is Hilbert space valued. Unconditional convergence for sequences from the abstract point of view of the function spaces of integrable functions is analyzed, and a version of the Kadec and Pelczynsky method for finding disjoint sequences for the vector measure setting is given. In the second chapter three notions of orthogonality of a sequence with respect to a vector measure are formally introduced, and the main characterizations of these sequences are given. Weak m-orthogonal sequences, (natural) m-orthogonal sequences and strongly m-orthogonal sequences are de ned and studied, providing also examples that show the relation with some classical problems in analysis. The geometry of these sets of sequences are also studied. In Chapter 3 we analyze almost everywhere convergence of weakm-orthogonal sequences. Our main result is a general vector measure version of the Mencho - Rademacher Theorem. A particular case involving c0-sums of Hilbert spaces is also intensively studied in order to show the properties of the convergence. Finally, Chapter 4 is devoted to show a concrete application. We develop an approximation method with respect to a parametric measure based on our ideas. A Bochner integrable function and an weak m-orthonormal sequence are the main elements of our procedure, that allows to nd the Fourier coefficients -that are in this case measurable functions- for a given function in the space L2(m). Some applications for signal approximation for data coming from experimental acoustics are also shown. / Jiménez Fernández, E. (2011). Vector measure orthogonal sequences in spaces of square integrable functions [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/13832 / Palancia
4

Desarrollo metodológico de evaluación ambiental en el análisis de procesos

Herrera Orozco, Israel 24 May 2004 (has links)
El desarrollo metodológico o modelo conceptual (MADAP) que se propone en este estudio, consta de cuatro fases o etapas. Dichas etapas permiten explorar todas las variables necesarias para el análisis de un proceso o actividad industrial, de manera que se involucren los aspectos ambientales en diferentes niveles de detalle. Las cuatro etapas son:· Análisis de procesos, de la cual se obtiene información acerca de los requerimientos y de las etapas necesarias para desarrollar la actividad.· Transferencia de información, esta etapa permite la transferencia de la información generada en el análisis de procesos, y que será utilizada en la evaluación ambiental.· Evaluación ambiental, donde se valoran desde las cargas ambientales identificadas, hasta los daños (reales y potenciales).· Toma de decisiones, las decisiones pueden estar basadas en los resultados obtenidos del análisis de procesos, después de la transferencia de información o a partir de cada uno de los niveles de la evaluación ambiental.En el análisis de proceso, se deben identificar todos y cada uno de los aspectos que posibilitan el funcionamiento de los procesos.Diferentes aspectos deben ser tenidos en cuenta en el análisis de procesos, y auque se describirán detalladamente en apartados posteriores de está memoria, se listan a continuación:· Definición de objetivos y alcance· Definición de las fronteras del sistema · Desarrollo de las etapas previas de diseño (diagramas, tuberías, etcétera)· Determinación de la incidencia ambiental· Nivel de la diferenciación espacial.· Costes directos o costes generados directamente debido a la producción· Costes Indirectos o costes no debidos a la producción, incluye los "Overheads"· Costes ambientales internos y externosLa segunda etapa de la metodología o transferencia de información desde el análisis de procesos se realiza a través de una interfaz (la cual está programada en Visual Basic). Esta transferencia, consiste básicamente en el desarrollo de tres etapas: 1) identificación de las variables que interviene en el proceso, 2) definición de los aspectos que posibilitan la interconexión, y 3) definición de la captura y envío de datos (importación/exportación de datos).La evaluación ambiental o tercera fase permite hacer una valoración de los procesos industriales, al analizar su incidencia ambiental. Esta evaluación, se basa en la descripción de los efectos y/o daños que pueden darse sobre la salud humana, los ecosistemas y los recursos naturales, a través de diferentes medios o compartimentos, tales como al aire, el agua, el suelo y sedimentos. Los efectos identificados, son determinados a través de la cuantificación de la carga ambiental debida a las sustancias nocivas, la concentración en los medios afectados, así como los efectos y daños ambientales en las diferentes áreas de protección.La cuarta fase, propone la utilización de métodos de comparación, que pueden ser aplicados en cada uno de los niveles de la evaluación ambiental y del análisis de procesos, y que van desde la comparación de los balances o inventarios, hasta la aplicación de un análisis coste-beneficio, cuando es posible monetizar los daños ambientales. Cuando la evaluación ambiental se centra en el nivel destino de contaminantes, es posible a través de la diferenciación espacial, comparar las zonas de mayor riesgo ambiental (destino de contaminantes). Así mismo, si la evaluación ambiental determina los efectos ambientales en términos de riesgos o impactos, estos pueden ser comparados, aunque no sea posible monetizarlos (e.g. impactos globales o riesgos en ecosistemas).A través de la última fase, se obtiene con suficiente validez científica, la mejor alternativa para un proceso, teniendo en cuenta su viabilidad técnica, económica y ambiental. / Methodological development or conceptual model proposed in this study is comprised of four phases or steps. Which permit to explore all the variables include in process and industrial activities, in order to involve the environmental aspects in different levels of detail.The phases included in the methodological development are:1. Process analysis, this phase proves information about the needed operations to develop the activity.2. Information transfer, this phase allows to transfer generated information in the process analysis, which will be utilised in the environmental assessment.3. Environmental assessment, where are identified environmental loads and damages (real and potential). 4. Decision-making, in this phase, decisions can be based on the results obtained from process analysis, after the transfer of information or from each one of the levels of the environmental evaluation. Several aspects should be kept in mind in process analysis:  Goal and scope definition  Burdens of the system Prior steps in process analysis (Diagrams, pipes, etc.) Level of the environmental assessment Level of the spatial differentiation Cost analysis (internal and external costs)The second phase of the methodology or transfer of information since the analysis of processes is carried out through an interface (which is programming in Visual Basic). The integration of information is realised in two stages: identification of variables, and capture- transference of data. The first stage allows identifying process streams and some basic information regarded to their role in the process (input/output, energy/material and product/by-product). An efficient procedure to perform this task is the process description, which can be easily made by a flowsheet analysis. Nevertheless, the variables in modelling and environmental assessment must have similar characteristics to create a consistent methodology. In the second stage, the process information is transferred and transformed, in order to be used by the subsequent stepThe environmental evaluation allows making an appraisal of the industrial processes, by means of environmental incidence. The description of the effects is bases on damages that can be given on the human health, the ecosystems and the natural resources, through different media or compartments, such as air, water, soil and sediments. The identifying effects, are you determined through the quantification of the environmental load due to the harmful substances, the concentration in the media affected, as well as the effects and environmental damages in the different areas of protection. The fourth phase proposes the comparison of several methods, that can be applied in each one of the levels of the environmental evaluation and of the analysis of processes, and that go since the comparison of the balances or inventories. This phase defines an environmental profile for industrial activities that includes from a material and energy balance, obtained by a life cycle inventory, a fate and exposure assessment for several routes and compartments or the impacts and risks for human and ecosystems, to a rigorous environmental damage profile. Furthermore, environmental effects in terms of risks or impacts can be compared. Through the last phase, is obtained with sufficient scientific validity, the best alternative for a process, keeping in mind its environmental, economic, and technical viability
5

Reactividad del fenol en soluciones acuosas de nitrito de sodio en presencia de micelas de sulfato de dodecilo de sodio / Reactividad del fenol en soluciones acuosas de nitrito de sodio en presencia de micelas de sulfato de dodecilo de sodio

Squadrito, Giuseppe, Fernández Lamarque, María de Fátima, Pryor, William 25 September 2017 (has links)
The rcactivity of phenol in aqueous solutions containing sodium ni tri te in the prescncc of sodium dodecylsulfate micellcs has bccn studied. Thc reaction yields ortho- and para-nitrophenol, para-nitrosophenol and 2,4-dinitrophenol at low convertions, in yiclds that depend on the pH. The rcsults ha ve been rationalized in terms of a reaction mechanism that involves free radicals.
6

Métodos estatísticos na análise de experimentos de microarray / Method Statistics in Microarrays Experiment Analisis

Cristo, Elier Broche 30 October 2003 (has links)
Neste trabalho é proposto um estudo comparativo de alguns métodos de Agrupamento (Hierárquico, K-médias e Self-Organizing Maps) e de Classificação (K-Vizinhos, Fisher, Máxima Verossimilhança, Aggregating e Regressão Local), os quais são apresentados teoricamente. Tais métodos são testados e comparados em conjuntos de dados reais, gerados com a técnica de Microarray. Esta técnica permite mensurar os níveis de expressão de milhares de genes simultaneamente, possibilitando comparações entre amostras de tecidos pelos perfis de expressão. É apresentada uma revisão de conceitos básicos relacionados ao processo de normalização, sendo este uma das primeiras etapas da análise deste tipo de conjunto de dados. Em particular, estivemos interessados em encontrar pequenos grupos de genes que fossem ?suficientes? para distinguir amostras em condições¸ biológicas diferentes. Por fim, é proposto um método de busca que, dado os resultados de um experimento envolvendo um grande número de genes, encontra de uma forma eficiente os melhores classificadores. / In this work we propose a comparative study of some clustering methods (Hierarchic, K -Means and Self-Organizing Maps) and some classification methods (K-Neighbours, Fisher, Maximum Likelihood, Aggregating and Local Regression), which are presented teoretically. The methods are tested and compared based on the analysis of some real data sets, generated from Microarray experiments. This technique allows for the measurement of expression levels from thousands of genes simultaneously, thus allowing the comparative analysis of sample of tissues in relation to their expression profile. We present a review of basic concepts regarding normalization of microarray data, one of the first steps in microarray analysis. In particular, we were interested in finding small groups of genes that were ?sufficient? to identify samples originating from different biological conditions. Finally, a search method is proposed, which will find efficiently the best classifiers from the results of an experiment involving a huge number of genes.
7

Análisis y control de convertidores continua-continua para módulos reguladores de baja tensión

Garcés Miguel, Pedro 27 November 2009 (has links)
El suministro de potencia para cargas que exigen altas corrientes, bajos voltajes y grandes y rápidos cambios en la corriente absorbida, además de una estrecha tolerancia en el voltaje de alimentación, representa un gran desafío al diseño de los convertidores para módulos reguladores de baja tensión. En esta tesis, se analizan distintas topologías de convertidores y controles susceptibles de ser aplicados en este tipo de sistemas de alimentación. Se propone una nueva topología de convertidor, la cual presenta frente a otras topologías utilizadas un mejor comportamiento ante los transitorios de la corriente de carga, además de poder trabajar con altas reducciones de voltaje. Del análisis realizado, se obtienen ecuaciones de diseño de este convertidor y de su control; siendo estas ecuaciones corroboradas mediante simulación PSIM, para un diseño sistemático del mismo. / Power supply for microprocessor boards is a great challenge, nowadays, in the field of power converters design for VRM. Microprocessors are exigent loads which require high current and low voltage, and also must react very fast to changes in consumption besides a voltage narrow tolerance range. This thesis analyzes several converters topologies and their controllers which satisfy the VRM requirements. The thesis proposes a new converter topology which has the fastest, among the analyzed topologies, behavior in front of abrupt consumption demand besides a high voltage reduction-ratio. We derive the design expressions for the DC-DC converter and the controller parameters according to the VRM specifications. The analysis has been corroborated by means of PSIM simulator. Simulation waveforms show a perfect agreement with previous analytical derivation.
8

Archyvo veiklos analizė / The analisis of Siauliai University archive proceeding Master’s work

Vaičaitienė, Elvyra 06 June 2005 (has links)
It is analysed the topic of the proceeding of Siauliai University archive, is given the analysis of the main conceptions, is discribed the particularity of the work in the Master’s work. It is analysed the proceeding of Lithuanian and foreign archives, is raised the necessity to introduce the new paperless basis of handling the information in order to make the posibility of the efective cooperation with ather institutions. It is emphasized the failings of handling the documents related to the formalizing the documents, preparation to save it, timely transfer for saving and filing as well as gathering. Is paid the grate attention to the rules of the official writting in the Master’s work because of the close connection with the efficiency of archivist’s work. It is given the comprehensive analysis juridical basis of the proceeding of Siauliai University archive, the main attention is paid to the acts and deeds whitch are related to rules of permise equipment and document saving. It is a must to reorganize the archive proceeding by usage of modern technologies, development and updation of the permise as well as cotact with foreign archives.
9

Modelos de marketing con datos de panel scanner.

Contreras Pérez, Carolina Faviola January 2003 (has links)
Seminario para optar al Título de Ingeniero Comercial, Mención Administración / En éste estudio nuestro objetivo es desarrollar un modelo donde podamos usar los datos de panel scanner para segmentar, sabemos que la segmentación para las empresas son muy importantes, sobre todo hoy en día donde la competencia es muy fuerte y la mayoría de las empresas tienen productos para segmentos específicos, por lo que segmentar es primordial para enfocar las estrategias de marketing, además como los datos de panel scanner reflejan la conducta real de compra de los consumidores podemos segmentar en base a esto y según el modelo que pretendemos utilizar obtener información sobre la estructura de mercado.
10

Métodos estatísticos na análise de experimentos de microarray / Method Statistics in Microarrays Experiment Analisis

Elier Broche Cristo 30 October 2003 (has links)
Neste trabalho é proposto um estudo comparativo de alguns métodos de Agrupamento (Hierárquico, K-médias e Self-Organizing Maps) e de Classificação (K-Vizinhos, Fisher, Máxima Verossimilhança, Aggregating e Regressão Local), os quais são apresentados teoricamente. Tais métodos são testados e comparados em conjuntos de dados reais, gerados com a técnica de Microarray. Esta técnica permite mensurar os níveis de expressão de milhares de genes simultaneamente, possibilitando comparações entre amostras de tecidos pelos perfis de expressão. É apresentada uma revisão de conceitos básicos relacionados ao processo de normalização, sendo este uma das primeiras etapas da análise deste tipo de conjunto de dados. Em particular, estivemos interessados em encontrar pequenos grupos de genes que fossem ?suficientes? para distinguir amostras em condições¸ biológicas diferentes. Por fim, é proposto um método de busca que, dado os resultados de um experimento envolvendo um grande número de genes, encontra de uma forma eficiente os melhores classificadores. / In this work we propose a comparative study of some clustering methods (Hierarchic, K -Means and Self-Organizing Maps) and some classification methods (K-Neighbours, Fisher, Maximum Likelihood, Aggregating and Local Regression), which are presented teoretically. The methods are tested and compared based on the analysis of some real data sets, generated from Microarray experiments. This technique allows for the measurement of expression levels from thousands of genes simultaneously, thus allowing the comparative analysis of sample of tissues in relation to their expression profile. We present a review of basic concepts regarding normalization of microarray data, one of the first steps in microarray analysis. In particular, we were interested in finding small groups of genes that were ?sufficient? to identify samples originating from different biological conditions. Finally, a search method is proposed, which will find efficiently the best classifiers from the results of an experiment involving a huge number of genes.

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