40 resultados para Condition-based maintenance

em Universidad Politécnica de Madrid


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This thesis presents a task-oriented approach to telemanipulation for maintenance in large scientific facilities, with specific focus on the particle accelerator facilities at European Organization for Nuclear Research (CERN) in Geneva, Switzerland and GSI Helmholtz Centre for Heavy Ion Research (GSI) in Darmstadt, Germany. It examines how telemanipulation can be used in these facilities and reviews how this differs from the representation of telemanipulation tasks within the literature. It provides methods to assess and compare telemanipulation procedures as well a test suite to compare telemanipulators themselves from a dexterity perspective. It presents a formalisation of telemanipulation procedures into a hierarchical model which can be then used as a basis to aid maintenance engineers in assessing tasks for telemanipulation, and as the basis for future research. The model introduces a new concept of Elemental Actions as the building block of telemanipulation movements and incorporates the dependent factors for procedures at a higher level of abstraction. In order to gain insight into realistic tasks performed by telemanipulation systems within both industrial and research environments a survey of teleoperation experts is presented. Analysis of the responses is performed from which it is concluded that there is a need within the robotics community for physical benchmarking tests which are geared towards evaluating the dexterity of telemanipulators for comparison of their dexterous abilities. A three stage test suite is presented which is designed to allow maintenance engineers to assess different telemanipulators for their dexterity. This incorporates general characteristics of the system, a method to compare kinematic reachability of multiple telemanipulators and physical test setups to assess dexterity from a both a qualitative perspective and measurably by using performance metrics. Finally, experimental results are provided for the application of the proposed test suite onto two telemanipulation systems, one from a research setting and the other within CERN. It describes the procedure performed and discusses comparisons between the two systems, as well as providing input from the expert operator of the CERN system.

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In Europe, Cardiovascular Diseases (CVD) are the leading source of death, causing 45% of all deceases. Besides, Heart Failure, the paradigm of CVD, mainly affects people older than 65. In the current aging society, the European MyHeart Project was created, whose mission is to empower citizens to fight CVD by leading a preventive lifestyle and being able to be diagnosed at an early stage. This paper presents the development of a Heart Failure Management System, based on daily monitoring of Vital Body Signals, with wearable and mobile technologies, for the continuous assessment of this chronic disease. The System makes use of the latest technologies for monitoring heart condition, both with wearable garments (e.g. for measuring ECG and Respiration); and portable devices (such as Weight Scale and Blood Pressure Cuff) both with Bluetooth capabilities

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In 2000, according to the World Health Organization, at least 171 million people, 2.8% of the population worldwide, suffered from diabetes. The Centres for Disease Control has defined it as an epidemic disease. Its incidence is increasing rapidly, and it is estimated that by 2030 this number will almost double. Diabetes mellitus occurs throughout the world, but is more common (especially type 2) in the more developed countries. Diabetes is a chronic condition that occurs when pancreas does not assure enough insulin secretion or when the body does not consume the insulin produced. Insulin is a hormone that regulates blood sugar. The effect of uncontrolled diabetes is the hyperglycaemia (blood sugar), which eventually seriously damage many organs and systems, especially the nerves and blood vessels. Diabetes type 2 (most common type of diabetes) is highly correlated with elderly people, obesity or overweight. Promoting a healthy lifestyle helps patients to improve their quality of life and in many cases to avoid complications related to the disease. This paper is intended to describe an iPhone-based application for self-management of type 2 diabetic patients, which allow them improving their lifestyle through healthy diet, physical activity and education

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La mayora de las estructuras de hormign pretensadas construidas en los ltimos 50 aos han demostrado una excelente durabilidad cuando su construccin se realiza atendiendo las recomendaciones de un buen diseo as como una buena ejecucin y puesta en obra de la estructura. Este hecho se debe en gran parte al temor que despierta el fenmeno de la corrosin bajo tensin tpico de las armaduras de acero de alta resistencia. Menos atencin se ha prestado a la susceptibilidad a la corrosin bajo tensin de los anclajes de postensado, posiblemente debido a que se han reportado pocos casos de fallos catastrficos. El concepto de Tolerancia al Dao y la Mecnica de la Fractura en estructuras de Ingeniera Civil ha empezado a incorporarse recientemente en algunas normas de diseo y clculo de estructuras metlicas, sin embargo, an est lejos de ser asimilado y empleado habitualmente por los ingenieros en sus clculos cuando la ocasin lo requiere. Este desconocimiento de los aspectos relacionados con la Tolerancia al Dao genera importantes gastos de mantenimiento y reparacin. En este trabajo se ha estudiado la aplicabilidad de los conceptos de la Mecnica de la Fractura a los componentes de los sistemas de postensado empleados en ingeniera civil, emplendolo para analizar la susceptibilidad de las armaduras activas frente a la corrosin bajo tensiones y a la prdida de capacidad portante de las cabezas de anclajes de postensado debido a la presencia de defectos. Con este objeto se han combinado tanto tcnicas experimentales como numricas. Los defectos superficiales en los alambres de pretensado no se presentan de manera aislada si no que existe una cierta continuidad en la direccin axial as como un elevado nmero de defectos. Por este motivo se ha optado por un enfoque estadstico, que es ms apropiado que el determinstico. El empleo de modelos estadsticos basados en la teora de valores extremos ha permitido caracterizar el estado superficial en alambres de 5,2 mm de dimetro. Por otro lado la susceptibilidad del alambre frente a la corrosin bajo tensin ha sido evaluada mediante la realizacin de una campaa de ensayos de acuerdo con la actual normativa que ha permitido caracterizar estadsticamente su comportamiento. A la vista de los resultados ha sido posible evaluar como los parmetros que definen el estado superficial del alambre pueden determinar la durabilidad de la armadura atendiendo a su resistencia frente a la corrosin bajo tensin, evaluada mediante los ensayos que especifica la normativa. En el caso de las cabezas de anclaje de tendones de pretensado, los defectos se presentan de manera aislada y tienen su origen en marcas, araazos o picaduras de corrosin que pueden producirse durante el proceso de fabricacin, transporte, manipulacin o puesta en obra. Dada la naturaleza de los defectos, el enfoque determinstico es ms apropiado que el estadstico. La evaluacin de la importancia de un defecto en un elemento estructural requiere la estimacin de la solicitacin local que genera el defecto, que permite conocer si el defecto es crtico o si puede llegar a serlo, si es que progresa con el tiempo (por fatiga, corrosin, una combinacin de ambas, etc.). En este trabajo los defectos han sido idealizados como grietas, de manera que el anlisis quedara del lado de la seguridad. La evaluacin de la solicitacin local del defecto ha sido calculada mediante el empleo de modelos de elementos finitos de la cabeza de anclaje que simulan las condiciones de trabajo reales de la cabeza de anclaje durante su vida til. A partir de estos modelos numricos se ha analizado la influencia en la carga de rotura del anclaje de diversos factores como la geometra del anclaje, las condiciones del apoyo, el material del anclaje, el tamao del defecto su forma y su posicin. Los resultados del anlisis numrico han sido contrastados satisfactoriamente mediante la realizacin de una campaa experimental de modelos a escala de cabezas de anclaje de Polimetil-metacrilato en los que artificialmente se han introducido defectos de diversos tamaos y en distintas posiciones. ABSTRACT Most of the prestressed concrete structures built in the last 50 years have demonstrated an excellent durability when they are constructed in accordance with the rules of good design, detailing and execution. This is particularly true with respect to the feared stress corrosion cracking, which is typical of high strength prestressing steel wires. Less attention, however, has been paid to the stress corrosion cracking susceptibility of anchorages for steel tendons for prestressing concrete, probably due to the low number of reported failure cases. Damage tolerance and fracture mechanics concepts in civil engineering structures have recently started to be incorporated in some design and calculation rules for metallic structures, however it is still far from being assimilated and used by civil engineers in their calculations on a regular basis. This limited knowledge of the damage tolerance basis could lead to significant repair and maintenance costs. This work deals with the applicability of fracture mechanics and damage tolerance concepts to the components of prestressed systems, which are used in civil engineering. Such concepts have been applied to assess the susceptibility of the prestressing steel wires to stress corrosion cracking and the reduction of load bearing capability of anchorage devices due to the presence of defects. For this purpose a combination of experimental work and numerical techniques have been performed. Surface defects in prestressing steel wires are not shown alone, though a certain degree of continuity in the axial direction exist. A significant number of such defects is also observed. Hence a statistical approach was used, which is assumed to be more appropriate than the deterministic approach. The use of statistical methods based in extreme value theories has allowed the characterising of the surface condition of 5.2 mm-diameter wires. On the other hand the stress corrosion cracking susceptibility of the wire has been assessed by means of an experimental testing program in line with the current regulations, which has allowed statistical characterisasion of their performances against stress corrosion cracking. In the light of the test results, it has been possible to evaluate how the surface condition parameters could determine the durability of the active metal armour regarding to its resistance against stress corrosion cracking assessed by means of the current testing regulations. In the case of anchorage devices for steel tendons for prestressing concrete, the damage is presented as point defects originating from dents, scratches or corrosion pits that could be produced during the manufacturing proccess, transport, handling, assembly or use. Due to the nature of these defects, in this case the deterministic approach is more appropriate than the statistical approach. The assessment of the relevancy of defect in a structural component requires the computation of the stress intensity factors, which in turn allow the evaluation of whether the size defect is critical or could become critical with the progress of time (due to fatigue, corrosion or a combination of both effects). In this work the damage is idealised as tiny cracks, a conservative hypothesis. The stress intensity factors have been calculated by means of finite element models of the anchorage representing the real working conditions during its service life. These numeric models were used to assess the impact of some factors on the rupture load of the anchorage, such the anchorage geometry, material, support conditions, defect size, shape and its location. The results from the numerical analysis have been succesfully correlated against the results of the experimental testing program of scaled models of the anchorages in poly-methil methacrylate in which artificial damage in several sizes and locations were introduced.

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Static analyses of object-oriented programs usually rely on intermediate representations that respect the original semantics while having a more uniform and basic syntax. Most of the work involving object-oriented languages and abstract interpretation usually omits the description of that language or just refers to the Control Flow Graph(CFG) it represents. However, this lack of formalization on one hand results in an absence of assurances regarding the correctness of the transformation and on the other it typically strongly couples the analysis to the source language. In this work we present a framework for analysis of object-oriented languages in which in a first phase we transform the input program into a representation based on Horn clauses. This allows on one hand proving the transformation correct attending to a simple condition and on the other being able to apply an existing analyzer for (constraint) logic programming to automatically derive a safe approximation of the semantics of the original program. The approach is flexible in the sense that the first phase decouples the analyzer from most languagedependent features, and correct because the set of Horn clauses returned by the transformation phase safely approximates the standard semantics of the input program. The resulting analysis is also reasonably scalable due to the use of mature, modular (C)LP-based analyzers. The overall approach allows us to report results for medium-sized programs.

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The advantages of tabled evaluation regarding program termination and reduction of complexity are well known as are the significant implementation, portability, and maintenance efforts that some proposals (especially those based on suspensin) require. This implementation effort is reduced by program transformation-based continuation cali techniques, at some erciency cost. However, the traditional formulation of this proposal by Ramesh and Cheng limits the interleaving of tabled and non-tabled predicates and thus cannot be used as-is for arbitrary programs. In this paper we present a complete translation for the continuation cali technique which, using the runtime support needed for the traditional proposal, solves these problems and makes it possible to execute arbitrary tabled programs. We present performance results which show that CCall offers a useful tradeoff that can be competitive with state-of-the-art implementations.

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Proof carrying code is a general methodology for certifying that the execution of an untrusted mobile code is safe, according to a predefined safety policy. The basic idea is that the code supplier attaches a certifcate (or proof) to the mobile code which, then, the consumer checks in order to ensure that the code is indeed safe. The potential benefit is that the consumer's task is reduced from the level of proving to the level of checking, a much simpler task. Recently, the abstract interpretation techniques developed in logic programming have been proposed as a basis for proof carrying code [1]. To this end, the certifcate is generated from an abstract interpretation-based proof of safety. Intuitively, the verification condition is extracted from a set of assertions guaranteeing safety and the answer table generated during the analysis. Given this information, it is relatively simple and fast to verify that the code does meet this proof and so its execution is safe. This extended abstract reports on experiments which illustrate several issues involved in abstract interpretation-based code certification. First, we describe the implementation of our system in the context of CiaoPP: the preprocessor of the Ciao multi-paradigm (constraint) logic programming system. Then, by means of some experiments, we show how code certification is aided in the implementation of the framework. Finally, we discuss the application of our method within the rea of pervasive systems which may lack the necessary computing resources to verify safety on their own. We herein illustrate the relevance of the information inferred by existing cost analysis to control resource usage in this context. Moreover, since the (rather complex) analysis phase is replaced by a simpler, efficient checking process at the code consumer side, we believe that our abstract interpretation-based approach to proof-carrying code becomes practically applicable to this kind of systems.

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The advantages of tabled evaluation regarding program termination and reduction of complexity are well known as are the significant implementation, portability, and maintenance efforts that some proposals (especially those based on suspension) require. This implementation effort is reduced by program transformation-based continuation call techniques, at some efficiency cost. However, the traditional formulation of this proposal by Ramesh and Cheng limits the interleaving of tabled and non-tabled predicates and thus cannot be used as-is for arbitrary programs. In this paper we present a complete translation for the continuation call technique which, using the runtime support needed for the traditional proposal, solves these problems and makes it possible to execute arbitrary tabled programs. We present performance results which show that CCall offers a useful tradeoff that can be competitive with state-of-the-art implementations.

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Reverberation chambers are well known for providing a random-like electric field distribution. Detection of directivity or gain thereof requires an adequate procedure and smart post-processing. In this paper, a new method is proposed for estimating the directivity of radiating devices in a reverberation chamber (RC). The method is based on the Rician K-factor whose estimation in an RC benefits from recent improvements. Directivity estimation relies on the accurate determination of the K-factor with respect to a reference antenna. Good agreement is reported with measurements carried out in near-field anechoic chamber (AC) and using a near-field to far-field transformation.

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This work describes a semantic extension for a user-smart object interaction model based on the ECA paradigm (Event-Condition-Action). In this approach, smart objects publish their sensing (event) and action capabilities in the cloud and mobile devices are prepared to retrieve them and act as mediators to configure personalized behaviours for the objects. In this paper, the information handled by this interaction system has been shaped according several semantic models that, together with the integration of an embedded ontological and rule-based reasoner, are exploited in order to (i) automatically detect incompatible ECA rules configurations and to (ii) support complex ECA rules definitions and execution. This semantic extension may significantly improve the management of smart spaces populated with numerous smart objects from mobile personal devices, as it facilitates the configuration of coherent ECA rules.

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A novel formulation for the surface impedance characterization is introduced for the canonical problem of surface fields on a perfect electric conductor (PEC) circular cylinder with a dielectric coating due to a electric current source using the Uniform Theory of Diffraction (UTD) with an Impedance Boundary Condition (IBC). The approach is based on a TE/TM assumption of the surface fields from the original problem. Where this surface impedance fails, an optimization is performed to minimize the error in the SD Green?s function between the original problem and the equivalent one with the IBC. This new approach requires small changes in the available UTD based solution with IBC to include the geodesic ray angle and length dependence in the surface impedance formulas. This asymptotic method, accurate for large separations between source and observer points, in combination with spectral domain (SD) Green?s functions for multidielectric coatings leads to a new hybrid SD-UTD with IBC to calculate mutual coupling among microstrip patches on a multilayer dielectric-coated PEC circular cylinder. Results are compared with the eigenfunction solution in SD, where a very good agreement is met.

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The implementation of a charging policy for heavy goods vehicles in European Union (EU) member countries has been imposed to reflect costs of construction and maintenance of infrastructure as well as externalities such as congestion, accidents and environmental impact. In this context, EU countries approved the Eurovignette directive (1999/62/EC) and its amending directive (2006 /38/EC) which established a legal framework to regulate the system of tolls. Even if that regulation seek s to increase the efficien cy of freight, it will trigger direct and indirect effects on Spains regional economies by increasing transport costs. This paper presents the development of a multiregional Input-Output methodology (MRIO) with elastic trade coefficients to predict in terregional trade, using transport attributes integrated in multinomial logit models. This method is highly useful to carry out an ex-ante evaluation of transport policies because it involves road freight transport cost sensitivity, and determine regional distributive and substitution economic effect s of countries like Spain, characterized by socio-demographic and economic attributes, differentiated region by region. It will thus be possible to determine cost-effective strategies, given different policy scenarios. MRIO mode l would then be used to determine the impact on the employment rate of imposing a charge in the Madrid-Sevilla corridor in Spain. This methodology is important for measuring the impact on the employment rate since it is one of the main macroeconomic indicators of Spains regional and national economic situation. A previous research developed (DESTINO) using a MRIO method estimated employment impacts of road pricing policy across Spanish regions considering a fuel tax charge (/liter) in the entire shortest cost path network for freight transport. Actually, it found that the variation in employment is expected to be substantial for some regions, and negligible for others. For example, in this Spanish case study of regional employment has showed reductions between 16.1% (Rioja) and 1.4% (Madrid region). This variation range seems to be related to either the intensity of freight transport in each region or dependency of regions to transport intensive economic sect ors. In fact, regions with freight transport intensive sectors will lose more jobs while regions with a predominantly service economy undergo a fairly insignificant loss of employment. This paper is focused on evaluating a freight transport vehicle-kilometer charge (/km) in a non-tolled motorway corridor (A-4) between Madrid-Sevilla (517 Km.). The consequences of the road pricing policy implementation show s that the employment reductions are not as high as the diminution stated in the previous research because this corridor does not affect the whole freight transport system of Spain.

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Fundamento de la tesis: Al comienzo del siglo XX, el inters por el turismo unido a la necesidad de restaurar un abundante patrimonio histrico, posibilit en Espaa que los poderes pblicos se embarcaran en una singular experiencia: la creacin de una infraestructura hotelera a partir de la rehabilitacin de edificios histricos. La preservacin, mantenimiento e incluso rentabilidad de una gran parte del patrimonio espaol se hara efectiva a travs de la innovadora frmula patrimonioturismo, cuya mxima expresin se materializ en la Red de Paradores desde su fundacin en la segunda dcada del siglo pasado hasta nuestros das. Sorprendentemente, este tema no ha sido todava investigado en su vertiente arquitectnica pese a que Espaa ha sido pionera y modelo en la cuestin de la hotelera pblica. Este trabajo aborda el estudio del caso ms significativo de todos los edificios de la red, en tanto que el patrimonio que ha servido de base a los fines hoteleros del Estado ha contado con un total de seis tipos arquitectnicos a lo largo de su historia, dentro de los cuales la arquitectura militar despunta con su mayoritaria presencia dentro del contexto de los edificios histricos de la red. El carcter arquetpico de los castillos y fortalezas, arraigado en el inconsciente colectivo, les hizo especialmente atractivos como alojamiento turstico al permitir evocar la remota poca medieval, pese a ser el tipo arquitectnico ms comprometido para la rehabilitacin hotelera. El estudio de las intervenciones operadas en estos inmuebles se revela de forma clara como escaparate de los distintos criterios de intervencin patrimonial que se han sucedido en el siglo XX, hasta enlazar con la perspectiva interdisciplinar actual. La tesis abarca en, primer lugar, diferentes aspectos generales relativos al promotor hotelero, la hotelera pblica de mbito nacional e internacional, y la caracterizacin de los inmuebles de la red estatal espaola, desde el punto de vista hotelero y arquitectnico, entendida esta ltima en sus tres escalas de influencia: la arquitectnica, la urbana o paisajstica, y la del interiorismo. Se analiza en segundo trmino la arquitectura militar dentro del contexto de la Red de Paradores, desde la consideracin de su transformacin hotelera, para lo cual ha sido necesario realizar una clasificacin propia, que abarca tanto edificios que respondieron a una estructura de cuartel, como castillospalacio, o fortalezas que haban servido a los fines de una orden religiosa militar, adems de considerarse las intervenciones en recintos histricos de carcter militar, donde se haca obligatorio construir de nueva planta. En tercer y ltimo lugar, se analiza a lo largo de las distintas etapas del organismo turstico las rehabilitaciones realizadas en estas construcciones militares, a la vez que se tienen en cuenta las intervenciones en los restantes edificios histricos, para evitar la descontextualizacin. Este recorrido comienza con la promocin de los dos primeros paradores a cargo del Comisario Regio, el marqus de la VegaIncln, que sirvieron para sentar las bases de los conceptos e ideas que habran de desarrollarse en las siguientes dcadas. Posteriormente, se desarroll y tom forma la red con el Patronato Nacional del Turismo, en la que las primeras intervenciones en tipos militares se tradujeron en reformas interiores de locales. La etapa clave de la red, y en particular de la arquitectura militar, tuvo lugar con el Ministerio de Informacin y Turismo, marcada por la repristinacin de monumentos, tras un perodo preparatorio con la Direccin General del Turismo en el que lo militar haba quedado de teln de fondo de otros tipos arquitectnicos. Tras el auge del Ministerio lleg el perodo de decadencia en el que los castillos y fortalezas desaparecieron de los intereses de las Secretarias de Turismo, hasta llegar a las inauguraciones de los novedosos establecimientos del siglo XXI y el resurgimiento del tipo militar con el parador de Lorca. Metodologa empleada: Este trabajo de investigacin se ha servido fundamentalmente de documentacin indita, procedente de diversos archivos, adems de una muy extensa toma de datos in situ. Dentro del patrimonio analizado, los inmuebles que responden al tipo arquitectnico militar se han dividido en tres grandes grupos: inmuebles rehabilitados que entraron en funcionamiento en la red, inmuebles en proceso de transformacin hotelera, e inmuebles que fueron adquiridos con fines hoteleros pero que no llegaron a rehabilitarse. Para cada uno de ellos ha sido necesario determinar en qu estado llegaron a manos de la Administracin Turstica, cul fue el mecanismo a travs del cual se adquirieron, en qu consisti su primera rehabilitacin hotelera, y cules fueron las ampliaciones o reformas ms significativas que se realizaron posteriormente. Estos datos se han sintetizado en fichas y se han extrado conclusiones al comparar cada unidad con el conjunto. Simultneamente se introdujeron dos factores externos: la historia del turismo que permiti hacer una ordenacin cronolgica de los inmuebles segn etapas, y la historia de la teora y prctica de la intervencin patrimonial en Espaa que permiti comparar los criterios patrimoniales de la Administracin competente respecto de las intervenciones de la Administracin Turstica, cuyo contacto se hara obligatorio a partir del Decreto, de 22 de abril de 1949, que dejaba bajo la tutela del Estado a todos los castillos y fortalezas. Aportacin de la tesis: Con carcter general, la tesis centra una ordenacin y sistematizacin completa del patrimonio inmobiliario de la red, desde el punto de vista de los tipos hoteleros y arquitectnicos, adems de poner por primera vez en conexin distintos modelos de hotelera pblica, para constituirse en el sustrato de futuras investigaciones. El estudio realizado se ha hecho extensivo a las distintas escalas que inciden de forma interconectada en la implantacin de un parador: la arquitectnica, la urbana y la del interiorismo, hasta ahora referenciado desde la exclusiva visin arquitectnica. Se han definido las etapas de la historia de la red, no ya slo a partir del hilo conductor de la cadena sucesiva de organismos tursticos, sino que por primera vez se hace en razn de la evolucin que sufren las intervenciones patrimoniales a lo largo del tiempo, a la vez que se entra en conexin con la teora y praxis de la restauracin monumental. Con carcter particular, la arquitectura militar dentro del contexto de los paradores se destaca en el perodo del Ministerio, en el que se experimentaron todas las posibilidades que presentaba su rehabilitacin. En este sentido se ha puesto de manifiesto en este trabajo un tipo hbrido de parador, a caballo entre la rehabilitacin y la edificacin de nueva planta, las dos formas bsicas de establecimiento creadas en la Comisara Regia, al que se ha denominado edificacin de nueva planta en recinto histrico militar. Esta nueva caracterizacin se ha valorado como la forma ms eficiente de implantar paradores, cuyas pautas arquitectnicas abarcaron un abanico de posibilidades: imitacin de modelos arquitectnicos histricos con utilizacin de elementos patrimoniales prestados que dieran el valor de la historia, utilizacin de un lenguaje moderno, o la inspiracin en la arquitectura verncula. La amalgama de elementos, estilos e intervenciones sucesivas de ampliacin fue la caracterstica comn tanto para la implantacin de un parador en un edificio como en un recinto amurallado. La arquitectura militar transformada en establecimiento hotelero evidencia la vocacin escenogrfica de las intervenciones patrimoniales, secundada por el interiorismo, adems de su aportacin a la arquitectura hotelera en lo referente al confort, organizacin y funcionamiento de sus instalaciones. La tesis ahonda en los diversos aspectos de la rehabilitacin hotelera apuntados de forma parcial por algunos autores, y pone de manifiesto la ambientacin medieval operada en la arquitectura militar, que lleg a tener su mxima expresin con el criterio de la unidad de estilo del Ministerio de Informacin y Turismo. La rehabilitacin hotelera dentro del contexto de la Red de Paradores, queda caracterizada en la tesis en relacin a intervenciones en construcciones militares, cuya sistematizacin puede ser extrapolable a otros tipos arquitectnicos o cadenas hoteleras de titularidad pblica, a partir del estudio que se ha avanzado en este trabajo. Thesis basis: At the beginning of the 20th century the interest in tourism added to the plentiful heritage in Spain enabled the authorities to embark on a singular experience: the creation of a hotel infrastructure from the restoration of historic buildings. Preservation, maintenance, and even profitability of a large part of the Spanish heritage would be effective through the innovative formula heritage-tourism. Its greatest expression materialized in the Paradores Network since its foundation in last centurys second decade to the present day. Surprisingly, this subject has not yet been investigated in its architectural aspect, even though Spain has been a pioneer and a model in the matter of public hotel business. This project tackles the study of the most significative case of all the networks buildings, since the heritage which has served throughout history as a base for the State hotel purposes has altogether six architectural types, among which military architecture stands out with its majority presence in the context of the historical buildings of the network. The archetypal character of castles and fortresses, ingrained in the collective subconscious, made them specially attractive for tourist accommodation, as it allowed the evocation of far medieval times, despite being the most awkward architectural type for hotel restoration. The study of the interventions in these buildings clearly reveals itself as a showcase of the different criteria of heritage intervention along the 20th century, connecting to the present interdisciplinary perspective. Firstly, the thesis covers different general aspects regarding the hotel developer, the domestic and international public hotel business, and the description of the Spanish state network buildings from a hotel business and an architectural point of view, the latter from its three influence scales: architectural, urban or landscape, and interior design. Secondly, the transformation of the military architecture in the Paradores Network into hotels is analyzed. For that purpose it was necessary to create a specific classification, which included barrack-structured buildings, castle-palaces, or fortresses which served the purposes of military-religious orders. The interventions in those military historical places where new building became compulsory were also taken into consideration. Thirdly and lastly, the thesis analyses the restorations in these military constructions through the different stages of the tourist organization. In order to avoid decontextualization, interventions in other historical buildings were also considered. This route begins with the promotion of the two first Paradores by the Royal Commissioner, the marquis of Vega-Incln, which paved the way for the concepts and ideas that were developed in the following decades. Subsequently, the network was developed and took shape with the National Tourism Board. The first interventions on military types were inside refurbishments. The Networks key period, and in particular of its military architecture, took place with the Ministry of Information and Tourism, a time marked by the restoration to its original state of monuments. This stage arrived after a preparatory period with the State Tourist Office, when the military type was left as a backdrop for other architectural types. After the Ministrys boom arrived a decline, in which castles and fortresses disappeared from the Tourist Departments interests up to the opening of the 21st century new establishments and the resurgence of the military type with Lorcas Parador. Methodology: The present research project has mainly used unpublished documentation from several archives and has done an extensive in situ data-gathering. Within the heritage analyzed, military buildings have been divided into three main groups: restored buildings that began to operate in the network, those in process of hotel transformation, and those acquired for hotel purposes, but which did not become restored. In each case, it has been necessary to determine the condition in which they arrived to the Tourist Administration, the procedure by which they were acquired, what their first hotel restoration consisted of, and which their subsequent most significative enlargements and alterations were. These facts have been synthesized in cards, and conclusions were drawn by comparing each unit with the whole. Simultaneously, two external factors were introduced: the history of tourism, that allowed establishing a chronological order according to different periods, and the history of Spanish heritage interventions theory and practice, that permitted to compare the heritage criteria from the competent Administration with those of the Tourist Administrations interventions. Both Administrations came compulsorily into contact after the Decree of 22nd April 1949, by which all castles and fortresses became under the protection of the State. Thesis contribution: In general, the thesis focuses on a complete order and systematization of the networks heritage buildings from the hotel and architectural types points of view, besides connecting for the first time different public hotel business models, becoming the substratum for future investigations. The study has included the different scales that impact interconnected on the establishment of a Parador: architectural, urban and interior design, only referenced to date from an architectural point of view. The Networks history stages have been defined according to not only a consecutive series of tourist organizations, but also, and for the first time, to the evolution of heritage interventions over time, thus connecting with the theory and praxis of monumental restoration. In particular, within the Paradores, military architecture stands out in the Ministrys period, in which all kind of restoration possibilities were explored. In this sense, the present project puts forth a hybrid type of Parador between restoration and new building, the two basic ways of establishment created in the Royal Commission, termed new building in military historic enclosure. This new characterization has been evaluated as the most efficient for establishing Paradores, whose architectonic guidelines include a wide range of possibilities: the imitation of historical architectonic models with use of borrowed heritage components that provide historical value, the use of modern language, or the inspiration in vernacular architecture. The amalgam of elements, styles and consecutive enlargement interventions was the common feature of the establishment of a Parador, both in a building or in a walled enclosure. The military architecture transformed into a hotel establishment gives proof of the scenographic vocation of heritage interventions, supported by interior design, as well as of its contribution to hotel architecture, related to its comfort, organization and the functioning of its facilities. The thesis delves into the diverse aspects of hotel restoration, partially pointed out by several authors, and puts forth the creation of a medieval atmosphere in military architecture, which came to its highest expression with the unitary style criteria of the Ministry of Information and Tourism. Hotel restoration within the context of the Paradores Network is defined in this thesis in relation to interventions in military constructions, whose systemization can be extrapolative to other architectural types or public hotel chains, based on the study which has been put forward in this project.

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This paper presents the design and implementation of an intelligent control system based on local neurofuzzy models of the milling process relayed through an Ehternet-based application. Its purpose is to control the spindle torque of a milling process by using an internal model control paradigm to modify the feed rate in real time. The stabilization of cutting cutting torque is especially necessary in milling processes such as high-spedd roughing of steel moulds and dies tha present minor geometric uncertainties. Thus, maintenance of the curring torque increaes the material removal rate and reduces the risk of damage due to excessive spindle vibration, a very sensitive and expensive component in all high-speed milling machines. Torque control is therefore an interesting challenge from an industrial point of view.

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El origen del proyecto se encuentra en la mejora de un inversor trifsico sinusoidal comercial sobre la base del estudio de las tcnicas de excitacin ptimas para los IGBTs que lo componen en su etapa de potencia. En las primeras fases de planteamiento del proyecto se propone una idea mucho ms ambiciosa, la realizacin de un nuevo convertidor de emergencia, destinado al sector ferroviario, para dar servicio de climatizacin. Este convertidor est formado por la asociacin en cascada de un bloque DC/DC elevador y un bloque inversor DC/AC trifsico controlado mediante PWM con modulacin sinusoidal. Se pretenda as dar solucin a las siguientes problemticas detectadas en los convertidores comercializados hasta el momento: un bloque elevador excesivamente sobredimensionado, subsistemas de control independientes para los dos bloques que configuran el convertidor, adicionalmente, la tarjeta driver se redisea con cada cambio de especificaciones por parte de un nuevo cliente y finalmente, las comunicaciones tanto de diagnosis como de mantenimiento necesitaban una importante actualizacin. Inicialmente, se ha realizado un estudio terico de los bloques elevador e inversor para poder realizar el diseo y dimensionamiento de sus componentes tanto semiconductores como electromagnticos. Una vez completada la parte de potencia, se estudia el control que se realiza mediante medidas directas y simulacin tanto de la estrategia de control del elevador como del inversor. As se obtiene una informacin completa de la funcionalidad de las tarjetas existentes. Se desea realizar el diseo de una nica tarjeta controladora y una nica tarjeta de drivers para ambos bloques. Por problemas ajenos, en el transcurso de este proyecto se cancela su realizacin comercial, con lo que se decide al menos crear la placa de control y poder gobernar un convertidor ya existente, sustituyendo la tarjeta de control del bloque elevador. Para poder fabricar la placa de control se divide en dos tarjetas que irn conectadas en modo sndwich. En una tarjeta est el microcontrolador y en otra est todo el interface necesario para operar con el sistema: entradas y salidas digitales, entradas y salidas analgicas, comunicacin CAN, y un pequeo DC/DC comercial que proporciona alimentacin al prototipo. Se realiza un pequeo programa funcional para poder manejar el convertidor, el cual con una tensin de 110V DC, proporciona a la salida una tensin de 380V AC. Como ya se ha expuesto, debido a la cancelacin del proyecto industrial no se profundiza ms en su mejora y se decide proponerlo para su evaluacin en su fase actual. ABSTRACT. The beginning of the project is found in the improvement of a commercial sine wave three phase inverter which is based in a study about optimal excitation techniques to IGBTs which compose in the power stage. In the early phases of project it is proposed a much more ambitious idea, the fact of a new emergency converter, proposed for the rail sector to work in an air condition unit. This converter is formed by an association of a block cascaded DC/DC booster and a block DC/AC inverter three-phase controlled by a sine wave modulation PWM. The purposed was to give a solution to following problems detected in commercial converters nowadays: an excessively oversized block boost, independent control subsystems for two blocks that configure the converter. In addition, driver board is redesigned with each specifications change demand it a new customer, and finally, the communications, diagnostic and maintenance that needed a important upgrade. Initially, it has been performed a theoretical study of boost and the inverter blocks to be able to perform the components design and the size (semiconductor and electromagnetic fields). Once finished power study, it is analysed the control performed using direct measures and simulation of boost control strategy and inverter. With this it is obtained complete information about existing cards functionality. The project is looking for the design of just one controller card and one drivers card for both blocks. By unrelated problems, during the course of this project a commercial realization. So at least its decided to create control board to be able to existing converter, replacing boost blocks control board. To be able to manufacture control board it is divided in two cards connected in sandwiching mode. In a card is microcontroller and in another is all needed interface to operate with the system: digital inputs and outputs, analogical inputs and outputs, CAN communication, and a small DC / DC business that provide power supply to the prototype. It is performed a small functional program to handle the converter, which with an input voltage 110V DC provides an output voltage 380V AC. As already has been exposed, due to industrial project cancellation it is decided no to continue with all improvements and directly to evaluate it in the current phase.