998 resultados para Passive revolution


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Desde la revolución ilustrada e industrial de finales del s. XVIII se ha venido desarrollando, con fuerza inigualada a lo largo de la historia, algo que es consustancial al hombre y que le ha permitido constituirse como tal frente al resto de animales: la técnica. Como sentencia Ortega, no hay hombre sin técnica. Pero, al mismo tiempo, va quedando cada vez más claro -como también nos señala Ortega- que el sentido y la causa de la técnica están fuera de ella, y que la técnica no es en rigor lo primero, sino que su finalidad le ha de ser prefijada por un deseo original pre-técnico. Si esto no fuera así el hombre perdería su propio sentido, pues el hombre es puro afán, un ente cuyo ser consiste no en lo que ya es, sino en la que aún no es. Sin embargo, el progresivo desencantamiento del mundo como consecuencia del desarrollo de la sociedad industrial vino a sustituir los viejos mitos por una interpretación racional y abstracta que renunciaba a cualquier búsqueda de sentido que trascendiese los hechos brutos. De este modo, la perdida de sentido del hombre frente a la técnica desarrollada por él mismo le dejaba desnortado y convertido en un sujeto pasivo en manos de un malentendido progreso. Frente a esta pérdida de sentido detectada ya a principios del siglo XX y denunciada con más fuerza a partir de la Segunda Guerra Mundial, el postmodernismo del último tramo del pasado siglo pudo no sólo oficializar su desaparición, sino consignar su deslegitimación. Ante a esto, sostenemos la necesaria existencia de sentido en cualquier arquitectura que se desarrolle plenamente y, especialmente, en la arquitectura de la modernidad -y aún de la modernidad tardía o postmodernidad- muchas de las veces no explicitado como tal frente al sobredimensionamiento técnico que ha venido marcando la pauta desde la revolución industrial. Al mismo tiempo, ya no se puede hablar de un único sentido, universalizable, sino de una pluralidad de sentidos que definirán distintas arquitecturas. Partiendo de la petitio principii de que el tema capital de la arquitectura en la modernidad ha sido la vivienda, el objeto arquitectónico que reúne las mejores características para desarrollar esta búsqueda de sentido lo hemos encontrado en la cabaña moderna, donde se cumple el aforismo corbusierano que señala que “quand l’économie est au maximum, l’intensité est au maximum”. Al mismo tiempo “al representar la plenitud a través de su misma negación”, la cabaña moderna se puede entender como una sublimación de la arquitectura a través de pequeños objetos donde han quedado destiladas las distintas esencias de la modernidad. Mediante el análisis de seis pequeñas construcciones situadas en archipiélagos arquitectónicos radicalmente distantes –el campamento de Ocatillo (F. Ll. Wright, 1929); la Caja (R. Erskine, 1942); el Cabanon (Le Corbusier, 1952); la casa cúpula en Carbondale (R. B. Fuller, 1960); el refugio en Oropesa (F. J. Sáenz de Oíza, c.1967-1977) y el pabellón de invitados en Kempsey (G. Murcutt, 1992)- la aparente aporía que supone la cabaña moderna, frente a la más lógica, en principio, cabaña primitiva, cobra sentido. Efectiva mente, el referente mítico de la cabaña primitiva, tal y como fue enunciado por Laugier, se correspondía con el estadio más primitivo de la modernidad, con sus orígenes, precisamente porque la crítica que se hacía en ella de la arquitectura se basaba en criterios exclusivamente técnicos que remitían a los orígenes constructivos de la arquitectura como fórmula para salir del entramado retórico en el que ésta se encontraba perdida. La cabaña moderna trasciende, sin embargo, aquella primitiva fase de la modernidad, de la que la cabaña de Laugier es paradigma, en la medida en que la crítica que se realiza ahora es doble, pues a la crítica de carácter técnico que encontramos en cada una de las cabañas se le añade una crítica de sentido que no se encuentra supeditada, en ninguno de los casos, a la componente técnica, tal y como sin embargo sucedía con Laugier, donde la pretendida regeneración moral de la arquitectura era consecuencia directa de su depuración técnica. En la cabaña moderna, al contrario, encontramos una pluralidad de sentidos que orientan y fuerzan el desarrollo de la techné en direcciones que llegan a ser radicalmente diferentes, construyendo unos relatos que habrán de ser, por tanto, necesariamente parciales, pero de los que la arquitectura, en cualquier caso no podrá prescindir si es que quiere seguir siendo fiel a sí misma, tal y como, efectivamente, lo comprendieron Wright, Erskine, Le Corbusier, Fuller, Sáenz de Oíza y Murcutt, cuando se esforzaron por que estas pequeñas arquitecturas que hemos visitado, tan sólo unas cabañas, fueran unas cabañas con sentido, unas cabañas modernas. ABSTRACT Since the illustrated and industrial revolution of the XVIII century it has been developing, with unequally strength through history, something that is inherent to man and that has allowed him to become himself against the rest of animals: technique. As Ortega says, there is no man without technique. But, at the same time, it is becoming increasingly clear –as Ortega also says- that the sense and the cause of the technique are beyond technique itself, and that technique is not actually the first thing, but that its purpose must be predefined by a pre-technique original desire. If it were not like this, man would lose his own sense, because man is pure desire, an entity whose being is not what already is, but what still doesn’t is. However, the progressive disenchantment of the world as the result of the development of the industrial society came to change the old myths by a rational and abstract interpretation that renounced to any search of meaning that transcended the brute facts. Thereby, the loss of sense of man against the technique developed by man himself let him aimless and converted in a passive object in the hands of a misunderstood progress. Against this loss of sense already detected at the beginning of the XX century and denounced in a stronger way since the Second World War, the postmodernism of the late decades of the last century could not only formalize its disappearance, but also consign its delegitimization. On the contrary, we maintain the necessary existence of sense in any architecture that is fully developed and, specially, in the modern architecture –and even in the late Modernism or Postmodernism- many times not made explicit as such against the technique oversizing that has been setting the pattern since the industrial revolution. At the same time, we can not talk about an only and universal sense, but about a plurality of senses that will define different architectures. On the basis of the petitio principii that dwelling has been the capital issue of modern architecture, the architectonic object that possesses the best features for developing this search of sense has been found in the modern hut, where is fulfil the Corbusieran aphorism that says that “quand l’économie est au maximum, l’intensité est au maximum”. At the same time, “representing plenitude through its own negation” the modern hut can be understood as a sublimation of architecture through small objects where the different essences of modernity have been distilled. Through the analysis of six small buildings located in radically distant architectonic archipelagos –the Ocatillo dessert camp (F. Ll. Wright, 1929); the Box (R. Erskine, 1942); the Cabanon (Le Corbusier, 1952); the dome-home in Carbondale (R. B. Fuller, 1960); the retreat in Oropesa (F. J. Sáenz de Oíza, c. 1967-1977) and the guest house in Kimpsey (G. Murcutt, 1992)- the apparent aporia that represents the modern hut, against the, initially, more logical primitive hut, makes sense. Indeed, the mythical reference of the primitive hut, as it was enunciated by Laugier, belonged to the most primitive state of modernity, with its origins, precisely because the criticism of the architecture that was made there was based in exclusively technique criteria, referring to the constructive origins of architecture as the formula to get out of the rhetoric labyrinth in which architecture was lost at the moment. However, the modern hut transcends that primitive phase of modernity, of which Laugier’s hut is paradigm, since the criticism that is made is double, because to the criticism on the technique that we find in every hut we must add a criticism on the sense that is never subordinated to the technique component, as it was the case in Laugier, where the intended architectonic moral regeneration was a direct consequence of its technical depuration. In the modern hut, on the contrary, we find a plurality of senses that guides and drives the development of techné in radically different directions, building narratives that must be, then, necessarilly partial, but of which architecture could never leave aside if it still wants to be faithful to itself, as Wright, Erskine, Le Corbusier, Fuller, Sáenz de Oíza and Murcutt seemed to understand when they tried hardly to make these small architectures that we have visited, these huts, huts full of sense, modern huts.

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Esta tesis está dedicada al análisis de las guías de onda y el diseño de los componentes pasivos con énfasis en aplicaciones de alta frecuencia. En primer lugar, se lleva a cabo el análisis de las guías de onda con conductores metálicos no ideales, con el objetivo de establecer el límite superior en frecuencia de las aproximaciones habitualmente utilizadas en microondas para el cálculo de las pérdidas óhmicas. Posteriormente, se presenta el diseño de diferentes componentes pasivos de guía de ondas: filtros, transductores de modos ortogonales (OMT), polarizadores, duplexores y alimentadores de antena, funcionando en frecuencias desde 10 a 750 GHz. Para el correcto diseño de componentes a altas frecuencias se requiere, en primer lugar, comprender los nuevos procesos de fabricación y después adecuar los diversos componentes para cumplir especificaciones eléctricas y geométricas simultáneamente. Para esto, se presentan modificaciones y nuevas geometrías de guiado de ondas para diferentes aplicaciones y procesos tecnológicos. Además se discuten sus ventajas sobre las soluciones ya existentes. Además, el trabajo presentado en esta tesis se ocupa del desarrollo completo de dispositivos: diseño, fabricación y caracterización de los componentes ya mencionados. Por último, algunos de los dispositivos desarrollados han sido diseñados para ser integrados en diferentes sistemas. De esta forma, se mejoran las prestaciones y capacidades de dichos sistemas.

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A passive neutron area monitor has been designed using Monte Carlo methods; the monitor is a polyethylene cylinder with pairs of thermoluminescent dosimeters (TLD600 and TLD700) as thermal neutron detector. The monitor was calibrated with a bare and a thermalzed 241AmBe neutron sources and its performance was evaluated measuring the ambient dose equivalent due to photoneutrons produced by a 15 MV linear accelerator for radiotherapy and the neutrons in the output of a TRIGA Mark III radial beam port.

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The existing seismic isolation systems are based on well-known and accepted physical principles, but they are still having some functional drawbacks. As an attempt of improvement, the Roll-N-Cage (RNC) isolator has been recently proposed. It is designed to achieve a balance in controlling isolator displacement demands and structural accelerations. It provides in a single unit all the necessary functions of vertical rigid support, horizontal flexibility with enhanced stability, resistance to low service loads and minor vibration, and hysteretic energy dissipation characteristics. It is characterized by two unique features that are a self-braking (buffer) and a self-recentering mechanism. This paper presents an advanced representation of the main and unique features of the RNC isolator using an available finite element code called SAP2000. The validity of the obtained SAP2000 model is then checked using experimental, numerical and analytical results. Then, the paper investigates the merits and demerits of activating the built-in buffer mechanism on both structural pounding mitigation and isolation efficiency. The paper addresses the problem of passive alleviation of possible inner pounding within the RNC isolator, which may arise due to the activation of its self-braking mechanism under sever excitations such as near-fault earthquakes. The results show that the obtained finite element code-based model can closely match and accurately predict the overall behavior of the RNC isolator with effectively small errors. Moreover, the inherent buffer mechanism of the RNC isolator could mitigate or even eliminate direct structure-tostructure pounding under severe excitation considering limited septation gaps between adjacent structures. In addition, the increase of inherent hysteretic damping of the RNC isolator can efficiently limit its peak displacement together with the severity of the possibly developed inner pounding and, therefore, alleviate or even eliminate the possibly arising negative effects of the buffer mechanism on the overall RNC-isolated structural responses.

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The integrated Safety Assessment (ISA) methodology, developed by the Spanish Nuclear Safety Council (CSN), has been applied to a thermal-hydraulic analysis of PWR Station Blackout (SBO) sequences in the context of the IDPSA (Integrated Deterministic-Probabilistic Safety Assessment) network objectives. The ISA methodology allows obtaining the damage domain (the region of the uncertain parameters space where the damage limit is exceeded) for each sequence of interest as a function of the operator actuations times. Given a particular safety limit or damage limit, several data of every sequence are necessary in order to obtain the exceedance frequency of that limit. In this application these data are obtained from the results of the simulations performed with MAAP code transients inside each damage domain and the time-density probability distributions of the manual actions. Damage limits that have been taken into account within this analysis are: local cladding damage (PCT>1477 K); local fuel melting (T>2499 K); fuel relocation in lower plenum and vessel failure. Therefore, to every one of these damage variables corresponds a different damage domain. The operation of the new passive thermal shutdown seals developed by several companies since Fukushima accident is considered in the paper. The results show the capability and necessity of the ISA methodology, or similar, in order to obtain accurate results that take into account time uncertainties.

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Presentación en poster de impresión 3D de guias de onda.

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La cuestión del asentamiento socialista en la URSS durante la década de 1920 estuvo caracterizada por el objetivo de definir y establecer un estado socialista en términos políticos, sociales y económicos. En este contexto de inestabilidad y cambio, un grupo de arquitectos pertenecientes a la Asociación de Arquitectos Contemporáneos, OSA, y liderado por Moisey Ginzburg, abordó el tema de la vivienda obrera asumiendo la responsabilidad y el compromiso por alcanzar un nuevo orden social. Su misión no consistió únicamente en solucionar el problema del alojamiento para los trabajadores en las grandes ciudades soviéticas, sino en redefinirlo como el marco adecuado para una sociedad sometida a un cambio sin precedentes que, al mismo tiempo y en un proceso dialéctico, debía contribuir a la construcción de esa nueva sociedad. La respuesta dada por la OSA trascendió el diseño inmediato bajo los estándares modernos establecidos en Occidente y tomó forma en un proceso de investigación que habría de prolongarse durante cinco años. Este trabajo, que culminó con la construcción y puesta en crisis de la Casa Narkomfin, se desarrolló en tres aproximaciones sucesivas. La primera, de carácter conceptual, consideró la participación ciudadana, así como de especialistas independientes, formalizándose en el Concurso entre Camaradas convocado por la OSA en 1926. La segunda aproximación al problema de la vivienda obrera se articuló a través de la investigación llevada a cabo por la Sección de Tipificación del Stroykom, esta vez desde premisas científicas y metodológicas. Finalmente, las conclusiones alcanzadas fueron transferidas a la práctica arquitectónica por medio de la construcción de seis Casas Experimentales de Transición, entre las que destacó la Casa Narkomfin. Este último acercamiento, de carácter empírico, ha sido tradicionalmente examinado por los expertos como un hecho aislado. Sin embargo, su estudio debe trascender necesariamente el genio del autor-creador en favor del proceso de investigación al que pertenece. En esta tesis, la Casa Narkomfin no se presenta sólo como el paradigma de vivienda soviética de vanguardia al que estamos acostumbrados, sino como un prototipo que recoge los principios y conclusiones alcanzados en las aproximaciones conceptuales y científicas precedentes. Únicamente desde este punto de vista cobra sentido la consideración de Ginzburg sobre su propio edificio como un medio propositivo y no impositivo: un proyecto concebido como una herramienta de transición hacia una sociedad más avanzada. ABSTRACT The question of mass housing in the USSR during the Twenties was marked by the drive to define and establish a socialist state in political, social and economic terms. In this context of instability and change, a group of architects gathered together under the Association of Contemporary Architects, OSA, led by Moisey Ginzburg, to address the issue of mass housing, thus taking on the responsibility and being committed to creating a new social order. Their quest not only involved solving the problem of housing for workers in large Soviet cities, but also redefining this solution as an appropriate framework for a society undergoing dramatic changes which, at the same time and in a dialectical process, would contribute to the creation of this new society. The solution provided by OSA transcended Modern standards of immediate design set by the West and was the result of a research process that would last five years. This work culminated in the construction of Narkomfin House and its self-criticism, developed in three successive approaches. The first was conceptual, being formalized in the Comradely Competition held by the OSA in 1926 and taking into account the participation of citizens and independent experts. The second approach to the problem of mass housing involved research developed by the Typification Section of the Stroykom, this time under scientific and methodological premises. Finally, the conclusions reached were put in practice with the construction of six Experimental Transitional Houses of which the most notable is Narkomfin House. This third empirical approach has traditionally been examined by scholars in isolation. However, its study must necessarily transcend the genius of the author-creator and involve the research process of which it is part. In this thesis, Narkomfin House is presented not only as the paradigm in Soviet housing avant-garde we are used to, but also as a prototype reflecting the principles and conclusions reached in the preceding conceptual and scientific approaches. Only from this point of view does Ginzburg’s understanding of his own building as a proactive and non-imposed environment make sense: a project conceived as a transition tool towards a more advanced society.

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The proliferation of video games and other applications of computer graphics in everyday life demands a much easier way to create animatable virtual human characters. Traditionally, this has been the job of highly skilled artists and animators that painstakingly model, rig and animate their avatars, and usually have to tune them for each application and transmission/rendering platform. The emergence of virtual/mixed reality environments also calls for practical and costeffective ways to produce custom models of actual people. The purpose of the present dissertation is bringing 3D human scanning closer to the average user. For this, two different techniques are presented, one passive and one active. The first one is a fully automatic system for generating statically multi-textured avatars of real people captured with several standard cameras. Our system uses a state-of-the-art shape from silhouette technique to retrieve the shape of subject. However, to deal with the lack of detail that is common in the facial region for these kind of techniques, which do not handle concavities correctly, our system proposes an approach to improve the quality of this region. This face enhancement technique uses a generic facial model which is transformed according to the specific facial features of the subject. Moreover, this system features a novel technique for generating view-independent texture atlases computed from the original images. This static multi-texturing system yields a seamless texture atlas calculated by combining the color information from several photos. We suppress the color seams due to image misalignments and irregular lighting conditions that multi-texturing approaches typically suffer from, while minimizing the blurring effect introduced by color blending techniques. The second technique features a system to retrieve a fully animatable 3D model of a human using a commercial depth sensor. Differently to other approaches in the current state of the art, our system does not require the user to be completely still through the scanning process, and neither the depth sensor is moved around the subject to cover all its surface. Instead, the depth sensor remains static and the skeleton tracking information is used to compensate the user’s movements during the scanning stage. RESUMEN La popularización de videojuegos y otras aplicaciones de los gráficos por ordenador en el día a día requiere una manera más sencilla de crear modelos virtuales humanos animables. Tradicionalmente, estos modelos han sido creados por artistas profesionales que cuidadosamente los modelan y animan, y que tienen que adaptar específicamente para cada aplicación y plataforma de transmisión o visualización. La aparición de los entornos de realidad virtual/mixta aumenta incluso más la demanda de técnicas prácticas y baratas para producir modelos 3D representando personas reales. El objetivo de esta tesis es acercar el escaneo de humanos en 3D al usuario medio. Para ello, se presentan dos técnicas diferentes, una pasiva y una activa. La primera es un sistema automático para generar avatares multi-texturizados de personas reales mediante una serie de cámaras comunes. Nuestro sistema usa técnicas del estado del arte basadas en shape from silhouette para extraer la forma del sujeto a escanear. Sin embargo, este tipo de técnicas no gestiona las concavidades correctamente, por lo que nuestro sistema propone una manera de incrementar la calidad en una región del modelo que se ve especialmente afectada: la cara. Esta técnica de mejora facial usa un modelo 3D genérico de una cara y lo modifica según los rasgos faciales específicos del sujeto. Además, el sistema incluye una novedosa técnica para generar un atlas de textura a partir de las imágenes capturadas. Este sistema de multi-texturización consigue un atlas de textura sin transiciones abruptas de color gracias a su manera de mezclar la información de color de varias imágenes sobre cada triángulo. Todas las costuras y discontinuidades de color debidas a las condiciones de iluminación irregulares son eliminadas, minimizando el efecto de desenfoque de la interpolación que normalmente introducen este tipo de métodos. La segunda técnica presenta un sistema para conseguir un modelo humano 3D completamente animable utilizando un sensor de profundidad. A diferencia de otros métodos del estado de arte, nuestro sistema no requiere que el usuario esté completamente quieto durante el proceso de escaneado, ni mover el sensor alrededor del sujeto para cubrir toda su superficie. Por el contrario, el sensor se mantiene estático y el esqueleto virtual de la persona, que se va siguiendo durante el proceso, se utiliza para compensar sus movimientos durante el escaneado.

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Buildings Indoor Air Quality requires a control in the Relative Humidity parameter. In passive architecture in humid climates relative humidity is even more important for human comfort and difficult to control. Therefore, nowadays, there is a research on dehumidifying systems. The present article shows an innovative dehumidifying panel composed of a plaster and Calcium Chloride salt. Laboratory tests are carried out to establish its viability as an indoor air moister regulator integrated in common plaster building interior coatings. There are two types of tests that have been carried out in two consecutive empirical phases: in the first phase, the tests of characterization of the Calcium Chloride as a desiccant are carried out; in a second phase, the dehumidifying panel as a whole is tested. Finally, both types of empirical tests show the efficiency and viability as an air moisture passive control system.

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Passive and active immunization against outer surface protein A (OspA) has been successful in protecting laboratory animals against subsequent infection with Borrelia burgdorferi. Antibodies (Abs) to OspA convey full protection, but only when they are present at the time of infection. Abs inactivate spirochetes within the tick and block their transmission to mammals, but do not affect established infection because of the loss of OspA in the vertebrate host. Our initial finding that the presence of high serum titers of anti-OspC Abs (5 to 10 μg/ml) correlates with spontaneous resolution of disease and infection in experimentally challenged immunocompetent mice suggested that therapeutic vaccination with OspC may be feasible. We now show that polyclonal and monospecific mouse immune sera to recombinant OspC, but not to OspA, of B. burgdorferi resolve chronic arthritis and carditis and clear disseminated spirochetes in experimentally infected C.B.-17 severe combined immunodeficient mice in a dose-dependent manner. This was verified by macroscopical and microscopical examination of affected tissues and recultivation of spirochetes from ear biopsies. Complete resolution of disease and infection was achieved, independent of whether OspC-specific immune sera (10 μg OspC-specific Abs) were repeatedly given (4× in 3- to 4-day intervals) before the onset (day 10 postinfection) or at the time of fully established arthritis and carditis (days 19 or 60 postinfection). The results indicate that in mice spirochetes constitutively express OspC and are readily susceptible to protective OspC-specific Abs throughout the infection. Thus, an OspC-based vaccine appears to be a candidate for therapy of Lyme disease.