668 resultados para Restrained Occupants.


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The aim of this study was (1) to examine whether childhood BMI is a significant predictor of restrained eating in preadolescents, (2) to investigate gender differences in restrained and emotional eating, and (3) to determine whether emotional problems, and body esteem were related to eating problems of preadolescents. In this longitudinal study with two measurement points, data from 428 children (50% female) were used. At time 1 (t1) children were on average 5.9 years old. BMI was assessed using objective measures. At time 2 (t2) participants were 12 years old. The adolescents and their parents completed questionnaires assessing restrained and emotional eating, body esteem, emotional problems, and BMI. Multiple regression analysis showed that restrained eating was significantly predicted by t1 BMI, by change in BMI between t1 and t2, and t2 body esteem. Emotional eating was, as expected, not predicted by t1 BMI, but associated with t2 body esteem and t2 emotional problems. Gender was not a significant predictor. The stability of BMI between childhood and preadolescence and its ability to predict restrained eating suggests that it is important to start prevention of overweight, body dissatisfaction and disordered eating at an early age

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Le temps des hommes doubles : Louis Aragon a désigné ainsi la séparation voire l’opposition entre l’homme social et l’homme privé dans la société capitaliste. Pour les auteurs réunis ici, il s’agit plutôt de signifier qu’au temps de la souveraineté nationale en armes, dès lors que sont plus rigoureusement assignées aux soldats et aux citoyens à la fois une « identité » et une « cause » supposées dépasser leur état civil et leurs intérêts particuliers, l’occupation militaire multiplie, dans la recherche d’accommodements entre les deux camps, les tensions et les combinaisons possibles entre fonctions ou statuts publics, sociabilités et influences locales, opinions et besoins. Pour caractériser les évolutions qui ont eu lieu entre les guerres déclarées par la France à l’Autriche en 1792 et à la Prusse en 1870, le présent livre met l’accent sur trois thèmes. Il traite d’abord des enjeux politiques et administratifs de l’occupation, parmi lesquels la neutralité, son devenir en tant que concept dans les relations internationales, et le positionnement des États neutres dans des conflits où l’on s’efforce de mobiliser aussi les opinions publiques. L’attention se porte ensuite sur les armées occupantes. Quelle que soit la part d’idéologie que l’autorité politique introduit dans leurs missions, la première de ces missions est de garantir leur propre sécurité. La recherche des accommodements ou le constat de l’extrême difficulté d’en trouver sont enfin abordés du point de vue des sociétés en proie à l’occupation. Dans ces situations où le présent peut être vécu et interprété en fonction d’une mémoire individuelle et collective d’expériences antérieures, le rôle joué par les occupants ne se réduit pas à la brutalité de la soldatesque et à l’exploitation économique.

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The enduring electoral success of populist parties across Europe and the increasing opportunities they have gained to access government in recent years bring once more into relief the question of whether populism and democracy are fully compatible. In this article we show how, despite playing different roles in government within very different political systems, and despite the numerous constraints placed upon them (for instance, EU membership, international law and domestic checks and balances), populist parties consistently pursued policies that clashed with fundamental tenets of liberal democracy. In particular, the idea that the power of the majority must be limited and restrained, the sanctity of individual rights and the principle of the division of powers have all come under threat in contemporary Europe. This has contributed to the continuing erosion of the liberal consensus, which has provided one of the fundamental foundations of the European project from its start.

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We present the first reference ranges for hematology (n = 35 animals), serum biochemistry (n = 62), and serum protein electrophoresis (n = 32) in physically restrained free-ranging roe deer (Capreolus capreolus). Animals were captured in box traps and physically restrained for blood sampling during the winter in Sweden, 2011-13. No clinically significant sex or age differences were found.

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Australia is unique as a populated continent in that canine rabies is exotic, with only one likely incursion in 1867. This is despite the presence of a widespread free-ranging dog population, which includes the naturalized dingo, feral domestic dogs and dingo-dog cross-breeds. To Australia's immediate north, rabies has recently spread within the Indonesian archipelago, with outbreaks occurring in historically free islands to the east including Bali, Flores, Ambon and the Tanimbar Islands. Australia depends on strict quarantine protocols to prevent importation of a rabid animal, but the risk of illegal animal movements by fishing and recreational vessels circumventing quarantine remains. Predicting where rabies will enter Australia is important, but understanding dog population dynamics and interactions, including contact rates in and around human populations, is essential for rabies preparedness. The interactions among and between Australia's large populations of wild, free-roaming and restrained domestic dogs require quantification for rabies incursions to be detected and controlled. The imminent risk of rabies breaching Australian borders makes the development of disease spread models that will assist in the deployment of cost-effective surveillance, improve preventive strategies and guide disease management protocols vitally important. Here, we critically review Australia's preparedness for rabies, discuss prevailing assumptions and models, identify knowledge deficits in free-roaming dog ecology relating to rabies maintenance and speculate on the likely consequences of endemic rabies for Australia.

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Measurements of the natural background radiation have been made at numerous places throughout the world. Very little work in this field has been done in developing countries. In Mexico the natural radiation to which the population is exposed has not been assessed. This dissertation represents a pioneer study in this environmental area. The radiation exposure which occupants within buildings receive as a result of naturally occurring radionuclides present in construction materials is the principal focus.^ Data were collected between August 1979 and November 1980. Continuous monitoring was done with TLDs placed on site for periods of 3 to 6 months. The instrumentation used for "real-time" measurements was a portable NaI (Tl) scintillation detector. In addition, radiometric measurements were performed on construction materials commonly used in Mexican homes.^ Based on TLD readings taken within 75 dwellings, the typical indoor exposure for a resident of the study area is 9.2 (mu)Rh('-1). The average reading of the 152 indoor scintillometer surveys was 9.5 (mu)Rh('-1), the outdoor reading 7.5 (mu)Rh('-1). Results of one-way and multi-way analyses of the exposure data to determine the effect due to building materials type, geologic subsoil, age of dwelling, and elevation are also presented. The results of 152 indoor scintillometer surveys are described. ^

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Manufactured housing has been found to have substantial levels of formaldehyde in the indoor air. Because mobile homes are more affordable than conventional housing, there has been a large increase in their use in the U.S. This increase in mobile home use has been substantial in the sunbelt regions such as Texas, where high temperatures and humidities may enhance out-gassing of formaldehyde and other volatile organic compounds from construction and furnishing materials and increase any potential health hazards.^ The influences of environmental, architectural and temporal factors on the presence of indoor formaldehyde and other organic compounds were investigated in conjunction with the Texas Indoor Air Quality Study of manufactured housing. A matched pair of mobile homes, one with electric heating and cooking utilities and the other with propane gas utilities, were used for a series of controlled experiments over a fourteen month period from October, 1982 through November, 1983.^ Over this fourteen month period formaldehyde levels decreased approximately 33%. Daily fluctuations of 20% to 40% were observed even with a constant indoor temperature. An increase in indoor temperature of 8(DEGREES)C doubled the measured formaldehyde concentration. Opening windows resulted in decreases of indoor formaldehyde levels of up to 50%. Studies of the impact of propane as a cooking source showed no increase in formaldehyde levels with stove use.^ The presence and concentration of selected volatile organic compounds is influenced greatest by occupancy. Occupants continually open and close windows and doors, vary the operation and settings (temperature) of air control systems, and vary in their selection of furnishings and use of consumer products, which may act as sources of indoor air contaminants. ^

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Objective: To assess the indoor environment of two different types of dental practices regarding VOCs, PM2.5, and ultrafine particulate concentrations and examine the relationship between specific dental activities and contaminant levels. Method: The indoor environments of two selected dental settings (private practice and community health center) will were assessed in regards to VOCs, PM 2.5, and ultrafine particulate concentrations, as well as other indoor air quality parameters (CO2, CO, temperature, and relative humidity). The sampling duration was four working days for each dental practice. Continuous monitoring and integrated sampling methods were used and number of occupants, frequency, type, and duration of dental procedures or activities recorded. Measurements were compared to indoor air quality standards and guidelines. Results: The private practice had higher CO2, CO, and most VOC concentrations than the community health center, but the community health center had higher PM2.5 and ultrafine PM concentrations. Concentrations of p-dichlorobenzene and PM2.5 exceeded some guidelines. Outdoor concentrations greatly influenced the indoor concentration. There were no significant differences in contaminant levels between the operatory and general area. Indoor concentrations during the working period were not always consistently higher than during the nonworking period. Peaks in particulate matter concentration occurred during root canal and composite procedures.^

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INTERACTION BETWEEN BRK AND HER2 IN BREAST CANCER Midan Ai, Ph.D. Supervisory Professor: Zhen Fan, M.D. Breast tumor kinase (Brk) is a nonreceptor protein-tyrosine kinase that is highly expressed in approximately two thirds of breast cancers but is not detectable or is expressed at very low levels in normal mammary epithelium. Brk plays important roles in promoting proliferation, survival, invasion, and metastasis of breast cancer cells, but the mechanism(s) of which remain largely unknown. Recent studies showed that Brk is frequently co-overexpressed with human epidermal growth factor receptor-2 (HER2) and is physically associated with HER2 in breast cancer. The mechanism needs to be determined. In my studies, I found that high expression of HER2 is correlated with high expression of Brk in breast cancer cell lines. Silencing HER2 expression via RNA interference in HER2 over-expressed breast cancer cells resulted in Brk protein decrease and overexpression of HER2 in HER2 low-expressed breast cancer cells up-regulated Brk expression. The mechanism study indicated that overexpression of HER2 increased Brk protein stability. Brk was degraded through a Ca2+-dependent protease pathway involving calpain and HER2 stimulated Brk expression via inhibiting calpain activity. Calpastatin is a calpain endogenous inhibitor and the calpain-calpastatin system has been implicated in a number of cell physiological functions. HER2 restrained calpain activation via up-regulating calpastatin expression and HER2 downstream signaling, MAPK pathway, was involved in the regulation. Furthermore, silencing of Brk expression by RNA interference in HER2-overexpressing breast cancer cells decreased HER2-mediated cell proliferation, survival, invasion/metastasis potential and increased cell sensitivity to HER2 kinase inhibitor, lapatinib, treatment, indicating that Brk plays important roles in regulating and mediating the oncogenic functions of HER2. The Stat3 pathway played important roles in Brk mediated cell survival and invasion/metastasis in the context of HER2-overexpressing breast cancer cells. However, transgenic mice with inducible expression of constitutively active Brk (CA) in the mammary epithelium failed to develop malignant change in the mammary glands after Brk induction for 15 months which indicated that expression of Brk protein alone was not sufficiently to induce spontaneous breast tumor. Bitransgenic mice with co-expression of HER2/neu and inducible expression of Brk in the mammary epithelium developed multifocal mammary tumors, but there were no significant difference in the tumor occurring time, tumor size, tumor weight and tumor multiplicity between the mouse group with co-expression of Brk and HER2/neu and the mouse group with HER2/neu expression only.

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El presente artículo se basa en los primeros resultados de un proyecto de investigación, cuyo objetivo general es caracterizar los procesos económicos, legales, urbanos y sociales que se llevan adelante, y los productos que se obtienen a partir de la acción de las familias, en el mercado informal de suelo urbano de la ciudad de Córdoba. La importancia de este proyecto, radica en que la fuente de información esencial, surge de entrevistas cualitativas a ocupantes de villas y asentamientos.

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The largest increase in export production in the eastern Pacific of the last 5.3 Myr (million years) occurred between 2.2 and 1.6 Myr, a time of major climatic and oceanographic reorganization in the region. Here, we investigate the causes of this event using reconstructions of export production, nutrient supply and oceanic conditions across the Pliocene-Pleistocene in the eastern equatorial Pacific (EEP) for the last 3.2 Myr. Our results indicate that the export production peak corresponds to a cold interval marked by high nutrient supply relative to consumption, as revealed by the low bulk sedimentary 15N/14N (d15N) and alkenone-derived sea surface temperature (SST) values. This ?0.6 million year long episode of enhanced delivery of nutrients to the surface of the EEP was predominantly initiated through the upwelling of nutrient-enriched water sourced in high latitudes. In addition, this phenomenon was likely promoted by the regional intensification of upwelling in response to the development of intense Walker and Hadley atmospheric circulations. Increased nutrient consumption in the polar oceans and enhanced denitrification in the equatorial regions restrained nutrient supply and availability and terminated the high export production event.

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En el estudio buscamos caracterizar el análisis de la SOSTENIBILIDAD (Suficiencia) del CICLO DE VIDA de una INFRAESTRUCTURA AEROPORTUARIA centrándonos en la evaluación de los aspectos SOCIALES (de forma Interdisciplinaria o Transversal) que le afectan y considerando todos los AGENTES involucrados (ingenieros/ operadores/ mantenedores/ usuarios/ stakeholders/ etc.). La complejidad de las interacciones entre los edificios y su entorno hace que sea difícil definir y evaluar con precisión la sostenibilidad de un edificio. Las NORMAS AMBIENTALES para la construcción (unas pocas existentes y algunos en fase de desarrollo) se centran en la sostenibilidad ECONÓMICA, SOCIAL Y AMBIENTAL que caracteriza a un edificio, siendo los aspectos socio-económicos difíciles de evaluar. En consecuencia, los métodos existentes para la evaluación de la construcción sostenible (por ejemplo, LEED, BREEAM, SBTool) tienden a superar los aspectos ambientales pues son más fáciles de evaluar de manera cuantitativa. Así desde el punto de vista holístico (global) y utilizando la teoría de sistemas complejos, la sostenibilidad debe ser evaluada, en parte, utilizando los INDICADORES DE SOSTENIBILIDAD SOCIALES Y ECONÓMICOS para cubrir todos los factores de Sostenibilidad. El estudio propone una metodología para valorar la sostenibilidad en la construcción aeroportuaria a través de la evaluación de los indicadores sostenibles de la construcción (SKPIs) sin y superando las carencias presentadas. Para ello hemos implementado una herramienta de evaluación de la sostenibilidad, donde: Puede evaluar, en primer aproximación e independientemente, la sostenibilidad del CICLO DE VIDA de la INFRAESTRUCTURA AEROPORTUARIA Puede COMPLETAR otras herramientas comerciales disponibles (ej. BREEAM, LEED), bajo un enfoque ECONÓMICO-SOCIAL y complementando el enfoque ambiental La evaluación de los KPIs se realiza por medio de TECNOLOGÍAS Y ESTRATEGIAS SOSTENIBLES, cuya aplicación supondría un aumento de la sostenibilidad del edificio La herramienta propuesta considera la complejidad y transdisciplinariedad del problema, fundada en un SISTEMA DE CRÉDITOS fácil de usar. Así el programa diseñado permite el análisis y la comparación del CICLO DE VIDA de la INFRAESTRUCTURA AEROPORTUARIA: Abarcando las etapas de construcción (diseño, operación, mantenimiento, etc.) Incluyendo a todos los agentes de construcción (ocupantes, stakeholders, constructores, etc.) Finalmente, se aporta un ejemplo teórico de una INFRAESTRUCTURA AEROPORTUARIA (Terminal Aeroportuaria) para fijar, demostrar y discutir el estudio presentado Abstract We seek to characterize the sustainability analysis of the life cycle of a building focus us on the evaluation of social aspect. From a holistic point of view and using complex systems theory, sustainability must be evaluated, in part, using social key performance indicator (KPI) to cover all factors of sustainability. The most remarkable of the proposed framework is to provide a methodology to achieve the sustainability in construction through the assessment of social KPIs. Besides we implement a tool to assess sustainability, where this tool could complete other commercial tools available (e.g. BREEAM, LEED). The proposed tool considers the complexity and trans-disciplinary of the problem. The procedure is based on a credit system easy to use. It also allows analysis and comparison of the boundary conditions of the building, embracing construction stages (design, operation), involving all the building agents (occupants, stakeholders, etc.)

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Hoy en día, el desarrollo tecnológico en el campo de los sistemas inteligentes de transporte (ITS por sus siglas en inglés) ha permitido dotar a los vehículos con diversos sistemas de ayuda a la conducción (ADAS, del inglés advanced driver assistance system), mejorando la experiencia y seguridad de los pasajeros, en especial del conductor. La mayor parte de estos sistemas están pensados para advertir al conductor sobre ciertas situaciones de riesgo, como la salida involuntaria del carril o la proximidad de obstáculos en el camino. No obstante, también podemos encontrar sistemas que van un paso más allá y son capaces de cooperar con el conductor en el control del vehículo o incluso relegarlos de algunas tareas tediosas. Es en este último grupo donde se encuentran los sistemas de control electrónico de estabilidad (ESP - Electronic Stability Program), el antibloqueo de frenos (ABS - Anti-lock Braking System), el control de crucero (CC - Cruise Control) y los más recientes sistemas de aparcamiento asistido. Continuando con esta línea de desarrollo, el paso siguiente consiste en la supresión del conductor humano, desarrollando sistemas que sean capaces de conducir un vehículo de forma autónoma y con un rendimiento superior al del conductor. En este trabajo se presenta, en primer lugar, una arquitectura de control para la automatización de vehículos. Esta se compone de distintos componentes de hardware y software, agrupados de acuerdo a su función principal. El diseño de la arquitectura parte del trabajo previo desarrollado por el Programa AUTOPIA, aunque introduce notables aportaciones en cuanto a la eficiencia, robustez y escalabilidad del sistema. Ahondando un poco más en detalle, debemos resaltar el desarrollo de un algoritmo de localización basado en enjambres de partículas. Este está planteado como un método de filtrado y fusión de la información obtenida a partir de los distintos sensores embarcados en el vehículo, entre los que encontramos un receptor GPS (Global Positioning System), unidades de medición inercial (IMU – Inertial Measurement Unit) e información tomada directamente de los sensores embarcados por el fabricante, como la velocidad de las ruedas y posición del volante. Gracias a este método se ha conseguido resolver el problema de la localización, indispensable para el desarrollo de sistemas de conducción autónoma. Continuando con el trabajo de investigación, se ha estudiado la viabilidad de la aplicación de técnicas de aprendizaje y adaptación al diseño de controladores para el vehículo. Como punto de partida se emplea el método de Q-learning para la generación de un controlador borroso lateral sin ningún tipo de conocimiento previo. Posteriormente se presenta un método de ajuste on-line para la adaptación del control longitudinal ante perturbaciones impredecibles del entorno, como lo son los cambios en la inclinación del camino, fricción de las ruedas o peso de los ocupantes. Para finalizar, se presentan los resultados obtenidos durante un experimento de conducción autónoma en carreteras reales, el cual se llevó a cabo en el mes de Junio de 2012 desde la población de San Lorenzo de El Escorial hasta las instalaciones del Centro de Automática y Robótica (CAR) en Arganda del Rey. El principal objetivo tras esta demostración fue validar el funcionamiento, robustez y capacidad de la arquitectura propuesta para afrontar el problema de la conducción autónoma, bajo condiciones mucho más reales a las que se pueden alcanzar en las instalaciones de prueba. ABSTRACT Nowadays, the technological advances in the Intelligent Transportation Systems (ITS) field have led the development of several driving assistance systems (ADAS). These solutions are designed to improve the experience and security of all the passengers, especially the driver. For most of these systems, the main goal is to warn drivers about unexpected circumstances leading to risk situations such as involuntary lane departure or proximity to other vehicles. However, other ADAS go a step further, being able to cooperate with the driver in the control of the vehicle, or even overriding it on some tasks. Examples of this kind of systems are the anti-lock braking system (ABS), cruise control (CC) and the recently commercialised assisted parking systems. Within this research line, the next step is the development of systems able to replace the human drivers, improving the control and therefore, the safety and reliability of the vehicles. First of all, this dissertation presents a control architecture design for autonomous driving. It is made up of several hardware and software components, grouped according to their main function. The design of this architecture is based on the previous works carried out by the AUTOPIA Program, although notable improvements have been made regarding the efficiency, robustness and scalability of the system. It is also remarkable the work made on the development of a location algorithm for vehicles. The proposal is based on the emulation of the behaviour of biological swarms and its performance is similar to the well-known particle filters. The developed method combines information obtained from different sensors, including GPS, inertial measurement unit (IMU), and data from the original vehicle’s sensors on-board. Through this filtering algorithm the localization problem is properly managed, which is critical for the development of autonomous driving systems. The work deals also with the fuzzy control tuning system, a very time consuming task when done manually. An analysis of learning and adaptation techniques for the development of different controllers has been made. First, the Q-learning –a reinforcement learning method– has been applied to the generation of a lateral fuzzy controller from scratch. Subsequently, the development of an adaptation method for longitudinal control is presented. With this proposal, a final cruise control controller is able to deal with unpredictable environment disturbances, such as road slope, wheel’s friction or even occupants weight. As a testbed for the system, an autonomous driving experiment on real roads is presented. This experiment was carried out on June 2012, driving from San Lorenzo de El Escorial up to the Center for Automation and Robotics (CAR) facilities in Arganda del Rey. The main goal of the demonstration was validating the performance, robustness and viability of the proposed architecture to deal with the problem of autonomous driving under more demanding conditions than those achieved on closed test tracks.

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La tesis revela paralelismos y conexiones entre las arquitectas/diseñadoras Charlotte Perriand (1903-1999) y Kazuyo Sejima (n. 1956), reflejados en una serie de proyectos de pequeña escala que denomino arquitectura petite—mobiliario tecnológico habitable—, resultado de momentos semejantes de cambio social, cultural, económico, industrial y transnacional en Francia en la década de 1920 y en Japón en la década de 1980. Este trabajo dirige su atención a la arquitectura doméstica concebida desde el interior por arquitectos con una formación complementaria en diseño de mobiliario. A su vez, profundiza en la relación que se establece entre el diseño de una casa y el diseño de un mueble, una máquina o un vestido. Los pequeños proyectos, próximos al mobiliario, diseñados por Sejima, no han sido suficientemente estudiados, al igual que los proyectos de arquitectura experimental proyectados por Perriand. Ambas trayectorias analizadas desde estos renovados puntos de vista se encuentran en lo que denominamos arquitectura petite. Surge así un nuevo paradigma espacial en un contexto de poder de lo femenino—en los medios de comunicación—y de intercambio cultural transnacional. Cuando el mobiliario crece y se equipa tecnológicamente para hacerse habitable por un grupo de personas, con cualidades suficientes de confort sensorial, es arquitectura petite. En 2009, Toyo Ito mostró en una conferencia en Madrid, una imagen de Sejima posando en su proyecto Pao I. Justo ochenta años antes, en 1929, Le Corbusier presentó en Buenos Aires la imagen de Perriand posando para su Chaise Longue. La coincidencia de ambas fotografías, junto con la lectura de dos inspiradores artículos de Toyo Ito, “Adèle’s dream” (1984)—cuyo enigmático título utiliza un nombre francés femenino para describir una casa japonesa—y “Simple lines for Le Corbusier” (1994), dieron origen a la hipótesis central de una investigación: la comparación de dos arquitectas, sus maestros y dos objetos pertenecientes a dos momentos y lugares distantes. Perriand y Sejima fueron emblemas del concepto de Nueva Feminidad, ambas tenían éxito en la prensa generalista del momento antes de ser contratadas por Le Corbusier y Toyo Ito respectivamente. Junto a sus maestros de entonces, concibieron dos iconos de la era de la maquina y de la electrónica respectivamente, la Chaise Longue (1928) y Pao I (1985), diseñados para ellas mismas. Perriand y Sejima usaron su propio cuerpo como unidad de medida y su imagen como reclamo publicitario para la promoción de los dos objetos respectivamente. La precisión técnica, materiales de lujo y enfoque de la relajación que compartieron la Chaise Longue y Pao I sugirió un nomadismo lúdico que anticipó el desarrollo posterior de lo que denominamos de arquitectura petite por parte de Perriand y Sejima. Ambos prototipos son los antecedentes de una arquitectura de talla precisa o petite (objetos híbridos entre casa, mueble y máquina con la sensualidad como característica distintiva) que ambas arquitectas han proyectado a lo largo de su carrera, y que aúnan su interés mutuo por las propiedades físicas de los materiales, así como su formación en diseño de mobiliario y su fascinación por la moda. La tesis concluye que la arquitectura petite es la depositaria de los manifiestos de una época, la que sigue a la era de la máquina enunciada por Le Corbusier y a la era de la electrónica descrita por Toyo Ito. En este sentido, la tesis evidencia la forma en la que importantes arquitectos han concentrado ideas ambiciosas en pequeños proyectos. Las características de petite se resumen en el hecho de ser una arquitectura de límites precisos, desmontable y por tanto temporal, que explora el potencial técnico y formal de nuevos materiales importados de otras industrias, incorpora condiciones sensuales propias de su escala antropométrica, y está destinada al ocio de un grupo de personas. A modo de colofón, la tesis descubre la existencia de una historia de ficción que vincula a Charlotte Perriand y Kazuyo Sejima a través de Toyo Ito: “El diario de Adèle”. ABSTRACT This dissertation reveals parallels between the architects/designers Charlotte Perriand (1903- 1999) and Kazuyo Sejima (b. 1956), reflected in a series of small projects I call petite architecture—habitable technological furniture—, which formed during similar periods of social, cultural, economic, industrial and transnational change in France in the 1920s and in Japan in the 1980s. This research focuses on domestic architecture conceived from the inside by architects with additional training in furniture design. At the same time, it explores the relationships established between the design of a house, a piece of furniture, a machine, or a dress. Small architectural projects, close to the furniture, designed by Sejima have not been sufficiently studied, as well as the experimental architectural projects designed by Perriand. Both of their experimental trajectories analyzed from this renovated point of view converge on what we call petite architecture. Thus, it raises a new spatial paradigm in the context of feminine power within the media, as direct consumers, and transnational cultural exchange. When furniture expands and is technologically equipped to the point where it becomes habitable by a group, or groups of people, providing its occupants with sensorial comfort, it is petite architecture. In 2009, at a conference in Madrid, Ito showed a picture of Sejima posing at his Pao I (1985). Just eighty years earlier, in 1929, Le Corbusier exhibited in a conference in Buenos Aires an image of Perriand posing for his Chaise Longue (1928). The coincidence of the two photographs, along with two inspiring articles by Toyo Ito "Adèle's dream" (1984) — whose enigmatic title uses a French female name to describe a Japanese house — and "Simple lines for Le Corbusier" (1994) led to a hypothesis and an investigation comparing the two architects, their mentors, and two objects, each belonging to two distant times and places. Perriand and Sejima were emblems of the concept of New Femininity, both had success in the media of their time before being hired by Le Corbusier and Toyo Ito respectively. Together with their mentors they designed two objects that became icons of the Machine Age and the Electronic Age respectively: the Chaise Longue (1928) and Pao I (1985). Designed "for themselves," Perriand and Sejima used their own bodies as a measuring unit and their image as a publicity stunt to promote the two objects respectively. Both objects are the embryonic capsules of the architecture that pampers the scale or petite (objects that conflate residence, machine and furniture, and have sensuality as a distinctive feature). From the technical precision, luxurious materials, and approach towards relaxation, emerged a playful nomadism, which anticipated the further development of what we call petite architecture. Perriand and Sejima would develop these ideas throughout their career, pooling their interests on the physical properties of materials, formation in furniture design, and their intense interest in fashion. The dissertation concludes that petite architecture is the manifestation of an age, which follows the Machine Age defined by Le Corbusier and the Electronic Age described by Toyo Ito. In this sense, the dissertation demonstrates the way in which important architects have focused their ambitious ideas on small projects. petite characteristics are summarized as being: architecture that pampers the scale, is (de)mountable and therefore temporary, explores the formal and technical potential of novel materials and techniques imported from other industries, incorporates sensual conditions according with its anthropometric scale, and is conceived for the leisure of a group of people. In addition, by way of colophon, the dissertation discovers the existence of a fictional story that links Charlotte Perriand and Kazuyo Sejima through Toyo Ito: "Adèle's Diary".

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El requerimiento de proveer alta frecuencia de datos en los modernos sistema de comunicación inalámbricos resulta en complejas señales moduladas de radio-frequencia (RF) con un gran ancho de banda y alto ratio pico-promedio (PAPR). Para garantizar la linealidad del comportamiento, los amplificadores lineales de potencia comunes funcionan típicamente entre 4 y 10 dB de back-o_ desde la máxima potencia de salida, ocasionando una baja eficiencia del sistema. La eliminación y restauración de la evolvente (EER) y el seguimiento de la evolvente (ET) son dos prometedoras técnicas para resolver el problema de la eficiencia. Tanto en EER como en ET, es complicado diseñar un amplificador de potencia que sea eficiente para señales de RF de alto ancho de banda y alto PAPR. Una propuesta común para los amplificadores de potencia es incluir un convertidor de potencia de muy alta eficiencia operando a frecuencias más altas que el ancho de banda de la señal RF. En este caso, la potencia perdida del convertidor ocasionado por la alta frecuencia desaconseja su práctica cuando el ancho de banda es muy alto. La solución a este problema es el enfoque de esta disertación que presenta dos arquitecturas de amplificador evolvente: convertidor híbrido-serie con una técnica de evolvente lenta y un convertidor multinivel basado en un convertidor reductor multifase con control de tiempo mínimo. En la primera arquitectura, una topología híbrida está compuesta de una convertidor reductor conmutado y un regulador lineal en serie que trabajan juntos para ajustar la tensión de salida para seguir a la evolvente con precisión. Un algoritmo de generación de una evolvente lenta crea una forma de onda con una pendiente limitada que es menor que la pendiente máxima de la evolvente original. La salida del convertidor reductor sigue esa forma de onda en vez de la evolvente original usando una menor frecuencia de conmutación, porque la forma de onda no sólo tiene una pendiente reducida sino también un menor ancho de banda. De esta forma, el regulador lineal se usa para filtrar la forma de onda tiene una pérdida de potencia adicional. Dependiendo de cuánto se puede reducir la pendiente de la evolvente para producir la forma de onda, existe un trade-off entre la pérdida de potencia del convertidor reductor relacionada con la frecuencia de conmutación y el regulador lineal. El punto óptimo referido a la menor pérdida de potencia total del amplificador de evolvente es capaz de identificarse con la ayuda de modelo preciso de pérdidas que es una combinación de modelos comportamentales y analíticos de pérdidas. Además, se analiza el efecto en la respuesta del filtro de salida del convertidor reductor. Un filtro de dampeo paralelo extra es necesario para eliminar la oscilación resonante del filtro de salida porque el convertidor reductor opera en lazo abierto. La segunda arquitectura es un amplificador de evolvente de seguimiento de tensión multinivel. Al contrario que los convertidores que usan multi-fuentes, un convertidor reductor multifase se emplea para generar la tensión multinivel. En régimen permanente, el convertidor reductor opera en puntos del ciclo de trabajo con cancelación completa del rizado. El número de niveles de tensión es igual al número de fases de acuerdo a las características del entrelazamiento del convertidor reductor. En la transición, un control de tiempo mínimo (MTC) para convertidores multifase es novedosamente propuesto y desarrollado para cambiar la tensión de salida del convertidor reductor entre diferentes niveles. A diferencia de controles convencionales de tiempo mínimo para convertidores multifase con inductancia equivalente, el propuesto MTC considera el rizado de corriente por cada fase basado en un desfase fijo que resulta en diferentes esquemas de control entre las fases. La ventaja de este control es que todas las corrientes vuelven a su fase en régimen permanente después de la transición para que la siguiente transición pueda empezar muy pronto, lo que es muy favorable para la aplicación de seguimiento de tensión multinivel. Además, el control es independiente de la carga y no es afectado por corrientes de fase desbalanceadas. Al igual que en la primera arquitectura, hay una etapa lineal con la misma función, conectada en serie con el convertidor reductor multifase. Dado que tanto el régimen permanente como el estado de transición del convertidor no están fuertemente relacionados con la frecuencia de conmutación, la frecuencia de conmutación puede ser reducida para el alto ancho de banda de la evolvente, la cual es la principal consideración de esta arquitectura. La optimización de la segunda arquitectura para más alto anchos de banda de la evolvente es presentada incluyendo el diseño del filtro de salida, la frecuencia de conmutación y el número de fases. El área de diseño del filtro está restringido por la transición rápida y el mínimo pulso del hardware. La rápida transición necesita un filtro pequeño pero la limitación del pulso mínimo del hardware lleva el diseño en el sentido contrario. La frecuencia de conmutación del convertidor afecta principalmente a la limitación del mínimo pulso y a las pérdidas de potencia. Con una menor frecuencia de conmutación, el ancho de pulso en la transición es más pequeño. El número de fases relativo a la aplicación específica puede ser optimizado en términos de la eficiencia global. Otro aspecto de la optimización es mejorar la estrategia de control. La transición permite seguir algunas partes de la evolvente que son más rápidas de lo que el hardware puede soportar al precio de complejidad. El nuevo método de sincronización de la transición incrementa la frecuencia de la transición, permitiendo que la tensión multinivel esté más cerca de la evolvente. Ambas estrategias permiten que el convertidor pueda seguir una evolvente con un ancho de banda más alto que la limitación de la etapa de potencia. El modelo de pérdidas del amplificador de evolvente se ha detallado y validado mediante medidas. El mecanismo de pérdidas de potencia del convertidor reductor tiene que incluir las transiciones en tiempo real, lo cual es diferente del clásico modelos de pérdidas de un convertidor reductor síncrono. Este modelo estima la eficiencia del sistema y juega un papel muy importante en el proceso de optimización. Finalmente, la segunda arquitectura del amplificador de evolvente se integra con el amplificador de clase F. La medida del sistema EER prueba el ahorro de energía con el amplificador de evolvente propuesto sin perjudicar la linealidad del sistema. ABSTRACT The requirement of delivering high data rates in modern wireless communication systems results in complex modulated RF signals with wide bandwidth and high peak-to-average ratio (PAPR). In order to guarantee the linearity performance, the conventional linear power amplifiers typically work at 4 to 10 dB back-off from the maximum output power, leading to low system efficiency. The envelope elimination and restoration (EER) and envelope tracking (ET) are two promising techniques to overcome the efficiency problem. In both EER and ET, it is challenging to design efficient envelope amplifier for wide bandwidth and high PAPR RF signals. An usual approach for envelope amplifier includes a high-efficiency switching power converter operating at a frequency higher than the RF signal's bandwidth. In this case, the power loss of converter caused by high switching operation becomes unbearable for system efficiency when signal bandwidth is very wide. The solution of this problem is the focus of this dissertation that presents two architectures of envelope amplifier: a hybrid series converter with slow-envelope technique and a multilevel converter based on a multiphase buck converter with the minimum time control. In the first architecture, a hybrid topology is composed of a switched buck converter and a linear regulator in series that work together to adjust the output voltage to track the envelope with accuracy. A slow envelope generation algorithm yields a waveform with limited slew rate that is lower than the maximum slew rate of the original envelope. The buck converter's output follows this waveform instead of the original envelope using lower switching frequency, because the waveform has not only reduced slew rate but also reduced bandwidth. In this way, the linear regulator used to filter the waveform has additional power loss. Depending on how much reduction of the slew rate of envelope in order to obtain that waveform, there is a trade-off between the power loss of buck converter related to the switching frequency and the power loss of linear regulator. The optimal point referring to the lowest total power loss of this envelope amplifier is identified with the help of a precise power loss model that is a combination of behavioral and analytic loss model. In addition, the output filter's effect on the response is analyzed. An extra parallel damping filter is needed to eliminate the resonant oscillation of output filter L and C, because the buck converter operates in open loop. The second architecture is a multilevel voltage tracking envelope amplifier. Unlike the converters using multi-sources, a multiphase buck converter is employed to generate the multilevel voltage. In the steady state, the buck converter operates at complete ripple cancellation points of duty cycle. The number of the voltage levels is equal to the number of phases according the characteristics of interleaved buck converter. In the transition, a minimum time control (MTC) for multiphase converter is originally proposed and developed for changing the output voltage of buck converter between different levels. As opposed to conventional minimum time control for multiphase converter with equivalent inductance, the proposed MTC considers the current ripple of each phase based on the fixed phase shift resulting in different control schemes among the phases. The advantage of this control is that all the phase current return to the steady state after the transition so that the next transition can be triggered very soon, which is very favorable for the application of multilevel voltage tracking. Besides, the control is independent on the load condition and not affected by the unbalance of phase current. Like the first architecture, there is also a linear stage with the same function, connected in series with the multiphase buck converter. Since both steady state and transition state of the converter are not strongly related to the switching frequency, it can be reduced for wide bandwidth envelope which is the main consideration of this architecture. The optimization of the second architecture for wider bandwidth envelope is presented including the output filter design, switching frequency and the number of phases. The filter design area is restrained by fast transition and the minimum pulse of hardware. The fast transition needs small filter but the minimum pulse of hardware limitation pushes the filter in opposite way. The converter switching frequency mainly affects the minimum pulse limitation and the power loss. With lower switching frequency, the pulse width in the transition is smaller. The number of phases related to specific application can be optimized in terms of overall efficiency. Another aspect of optimization is improving control strategy. Transition shift allows tracking some parts of envelope that are faster than the hardware can support at the price of complexity. The new transition synchronization method increases the frequency of transition, allowing the multilevel voltage to be closer to the envelope. Both control strategies push the converter to track wider bandwidth envelope than the limitation of power stage. The power loss model of envelope amplifier is detailed and validated by measurements. The power loss mechanism of buck converter has to include the transitions in real time operation, which is different from classical power loss model of synchronous buck converter. This model estimates the system efficiency and play a very important role in optimization process. Finally, the second envelope amplifier architecture is integrated with a Class F amplifier. EER system measurement proves the power saving with the proposed envelope amplifier without disrupting the linearity performance.