27 resultados para reviewing

em Universidad Politécnica de Madrid


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Any scientific publication aims to advance the field of knowledge that it deals with, and therefore the editorial staff will always be seeking the most revolutionary papers among all of those received. On the other hand, the reviewers’ task is usually a much more conservative one, as reviewers are responsible for verifying the realism of the methods proposed and the veracity of the claimed results.

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Empirical Software Engineering (ESE) replication researchers need to store and manipulate experimental data for several purposes, in particular analysis and reporting. Current research needs call for sharing and preservation of experimental data as well. In a previous work, we analyzed Replication Data Management (RDM) needs. A novel concept, called Experimental Ecosystem, was proposed to solve current deficiencies in RDMapproaches. The empirical ecosystem provides replication researchers with a common framework that integrates transparently local heterogeneous data sources. A typical situation where the Empirical Ecosystem is applicable, is when several members of a research group, or several research groups collaborating together, need to share and access each other experimental results. However, to be able to apply the Empirical Ecosystem concept and deliver all promised benefits, it is necessary to analyze the software architectures and tools that can properly support it.

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Determining as accurate as possible spent nuclear fuel isotopic content is gaining importance due to its safety and economic implications. Since nowadays higher burn ups are achievable through increasing initial enrichments, more efficient burn up strategies within the reactor cores and the extension of the irradiation periods, establishing and improving computation methodologies is mandatory in order to carry out reliable criticality and isotopic prediction calculations. Several codes (WIMSD5, SERPENT 1.1.7, SCALE 6.0, MONTEBURNS 2.0 and MCNP-ACAB) and methodologies are tested here and compared to consolidated benchmarks (OECD/NEA pin cell moderated with light water) with the purpose of validating them and reviewing the state of the isotopic prediction capabilities. These preliminary comparisons will suggest what can be generally expected of these codes when applied to real problems. In the present paper, SCALE 6.0 and MONTEBURNS 2.0 are used to model the same reported geometries, material compositions and burn up history of the Spanish Van de llós II reactor cycles 7-11 and to reproduce measured isotopies after irradiation and decay times. We analyze comparisons between measurements and each code results for several grades of geometrical modelization detail, using different libraries and cross-section treatment methodologies. The power and flux normalization method implemented in MONTEBURNS 2.0 is discussed and a new normalization strategy is developed to deal with the selected and similar problems, further options are included to reproduce temperature distributions of the materials within the fuel assemblies and it is introduced a new code to automate series of simulations and manage material information between them. In order to have a realistic confidence level in the prediction of spent fuel isotopic content, we have estimated uncertainties using our MCNP-ACAB system. This depletion code, which combines the neutron transport code MCNP and the inventory code ACAB, propagates the uncertainties in the nuclide inventory assessing the potential impact of uncertainties in the basic nuclear data: cross-section, decay data and fission yields

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Several chemical reactions are able to produce swelling of concrete for decades after its initial curing, a problem that affects a considerable number of concrete dams around the world. Principia has had several contracts to study this problem in recent years, which have required reviewing the state-ofthe-art, adopting appropriate mathematical descriptions, programming them into user routines in Abaqus, determining model parameters on the basis of some parts of the dams’ monitored histories, ensuring reliability using some other parts, and finally predicting the future evolution of the dams and their safety margins. The paper describes some of the above experience, including the programming of sophisticated nonisotropic swelling models, that must be compatible with cracking and other nonlinearities involved in concrete behaviour. The applications concentrate on two specific cases, an arch-gravity dam and a double-curvature arch dam, both with a long history of concrete swelling and which, interestingly, entailed different degrees of success in the modelling efforts

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Several chemical reactions are able to produce swelling of concrete for decades after its initial curing, a problem that affects a considerable number of concrete dams around the world. Principia has had several contracts to study this problem in recent years, which have required reviewing the state-of-the-art, adopting appropriate mathematical descriptions, programming them into user routines in Abaqus, determining model parameters on the basis of some parts of the dams’ monitored histories, ensuring reliability using some other parts, and finally predicting the future evolution of the dams and their safety margins. The paper describes some of the above experience, including the programming of sophisticated non-isotropic swelling models, that must be compatible with cracking and other nonlinearities involved in concrete behaviour. The applications concentrate on two specific cases, an archgravity dam and a double-curvature arch dam, both with a long history of concrete swelling and which, interestingly, entailed different degrees of success in the modelling efforts

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Free people association constructed from button to above to get better conditions of people using local resources, are among others, elements of local development. LEADER (Liaisons HQWUH DFWLYLWpV GH 'HYHORSHPHQW GH /¶(FRQRPLH 5XUDO) is the Europe Union model of rural development. The LEADER method is conformed in seven features which are factors of success in the approach of applying in different territories . The actions held in the municipal council of rural development of San Andres C a l p a n during 2010 showed some elements of LEADER for it´s adjustment: 1).- territory definition , 2).- local association , 3).- financing. It´s used a methodology consists of reviewing documents about the financing and association in the territory studied, survey applying t define the model of agricultural production and development along with mayors of different municipalities, the economical and social actors. The definition performance field with territory integration of citizen councils as groups of local action and a financing strategy are part of the results of this process of adapting in this territory

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Several chemical reactions are able to produce swelling of concrete for decades after its initial curing, a problem that affects a considerable number of concrete dams around the world. Principia has had several contracts to study this problem in recent years, which have required reviewing the state-ofthe-art, adopting appropriate mathematical descriptions, programming them into user routines in Abaqus, determining model parameters on the basis of some parts of the dams’ monitored histories, ensuring reliability using some other parts, and finally predicting the future evolution of the dams and their safety margins. The paper describes some of the above experience, including the programming of sophisticated nonisotropic swelling models, that must be compatible with cracking and other nonlinearities involved in concrete behaviour. The applications concentrate on two specific cases, an arch-gravity dam and a double-curvature arch dam, both with a long history of concrete swelling and which, interestingly, entailed different degrees of success in the modelling efforts.

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El peso específico de las Comunicaciones Ópticas dentro del ámbito de la Ingeniería de Telecomunicación no cesa de crecer. Sus aplicaciones, inicialmente dedicadas a las grandes líneas que enlazan las centrales de conmutación, alcanzan en la actualidad, como se ha mencionado, hasta los mismos hogares. Los progresos en este campo, con una sucesión sin tregua, no sólo se destinan a incrementar la capacidad de transmisión de los sistemas, sino a ampliar la diversidad de los procesos que sobre las señales se efectúan en el dominio óptico. Este dinamismo demanda a los profesionales del sector una revisión y actualización de sus conocimientos que les permitan resolver con soltura las cuestiones de su actividad de ingeniería. Por otra parte, durante los últimos años la importancia de las Comunicaciones Ópticas también se ha reflejado en las diferentes titulaciones de Ingenierías de Telecomunicación, cuyos planes de estudio contemplan esta materia tanto en asignaturas troncales como optativas. A menudo, las fuentes de información disponibles abordan esta disciplina con una orientación principalmente teórica. Profesionales y estudiantes de Ingeniería, pues, frente a esta materia se encuentran unos temas que tratan fenómenos físicos complejos, abundantes en conceptos abstractos y con un florido aparato matemático, pero muchas veces carentes de una visión práctica, importantísima en ingeniería, y que es, en definitiva, lo que se exige a alumnos e ingenieros: saber resolver problemas y cuestiones relacionados con las Comunicaciones Ópticas. Los sistemas de comunicaciones ópticas, y en especial aquellos que utilizan la fibra óptica como medio para la transmisión de información, como se ha dicho, están alcanzando un desarrollo importante en el campo de las telecomunicaciones. Las bondades que ofrece la fibra, de sobra conocidos y mencionados en el apartado que antecede (gran ancho de banda, inmunidad total a las perturbaciones de origen electromagnético, así como la no producción de interferencias, baja atenuación, etc.), han hecho que, hoy en día, sea uno de los campos de las llamadas tecnologías de la información y la comunicación que presente mayor interés por parte de científicos, ingenieros, operadores de telecomunicaciones y, por supuesto, usuarios. Ante esta realidad, el objetivo y justificación de la realización de este proyecto, por tanto, no es otro que el de acercar esta tecnología al futuro ingeniero de telecomunicaciones, y/o a cualquier persona con un mínimo de interés en este tema, y mostrarle de una forma práctica y visual los diferentes fenómenos que tienen lugar en la transmisión de información por medio de fibra óptica, así como los diferentes bloques y dispositivos en que se divide dicha comunicación. Para conseguir tal objetivo, el proyecto fin de carrera aquí presentado tiene como misión el desarrollo de una interfaz gráfica de usuario (GUI, del inglés Graphic User Interface) que permita a aquel que la utilice configurar de manera sencilla cada uno de los bloques en que se compone un enlace punto a punto de fibra óptica. Cada bloque en que se divide este enlace estará compuesto por varias opciones, que al elegir y configurar como se quiera, hará variar el comportamiento del sistema y presentará al usuario los diferentes fenómenos presentes en un sistema de comunicaciones ópticas, como son el ruido, la dispersión, la atenuación, etc., para una mejor comprensión e interiorización de la teoría estudiada. Por tanto, la aplicación, implementada en MATLAB, fruto de la realización de este PFC pretende servir de complemento práctico para las asignaturas dedicadas al estudio de las comunicaciones ópticas a estudiantes en un entorno amigable e intuitivo. Optical Communications in the field of Telecommunications Engineering continues to grow. Its applications, initially dedicated to large central lines that link the switching currently achieved, as mentioned, to the same household nowadays. Progress in this field, with a relentless succession, not only destined to increase the transmission capacity of the systems, but to broaden the diversity of the processes that are performed on the signals in the optical domain. This demands to professionals reviewing and updating their skills to enable them resolve issues easily. Moreover, in recent years the importance of optical communications is also reflected in the different degrees of Telecommunications Engineering, whose curriculum contemplates this area. Often, the information sources available to tackle this discipline mainly theoretical orientation. Engineering professionals and students are faced this matter are few topics discussing complex physical phenomena, and abstract concepts abundant with a flowery mathematical apparatus, but often wotput a practical, important in engineering, and that is what is required of students and engineers: knowing how to solve problems and issues related to optical communications. Optical communications systems, particularly those using optical fiber as a medium for transmission of information, as stated, are reaching a significant development in the field of telecommunications. The advantages offered by the fiber, well known and referred to in the preceding paragraph (high bandwidth, immunity to electromagnetic disturbances of origin and production of non interference, low attenuation, etc..), have made today, is one of the fields of information and communication technology that this increased interest by scientists, engineers, telecommunications operators and, of course, users. Given this reality, the purpose and justification of this project is not other than to bring this technology to the future telecommunications engineer, and / or anyone with a passing interest in this subject, and showing of a practical and various visual phenomena occurring in the transmission of information by optical fiber, as well as different blocks and devices in which said communication is divided. To achieve that objective, the final project presented here has as its mission the development of a graphical user interface (GUI) that allows the user to configure each of the blocks in which divided a point-to-point optical fiber. Each block into which this link will consist of several options to choose and configure it as you like, this will change the behavior of the system and will present to the user with the different phenomena occurring in an optical communication system, such as noise, dispersion, attenuation, etc., for better understanding and internalization of the theory studied. Therefore, the application, implemented in MATLAB, the result of the completion of the thesis is intended to complement practical subjects for the study of optical communications students in a friendly and intuitive environment.

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La tesis doctoral “Mejoras Tecnológicas en el Reciclado de Residuos de Construcción y Demolición (RCD)” investiga la utilización de los separadores hidráulicos para mejorar la calidad de los áridos reciclados, y se demuestra que es un equipo más eficiente que las técnicas actuales basadas en la simple separación por densidad. En la tesisn se ha realizado inicialmente una revisión de la situación del sector, para a continuación centrarse en los sistemas de separación utilizados en las plantas de valorización españolas. Una vez analizados éstos y en particular los de tipo hidráulico, de los que se resume un estudio comparativo, se ha procedido a ensayar a escala de Laboratorio el comportamiento de un separador hidráulico de aceleración diferencial con diversos materiales procedentes de tres plantas de reciclaje. Adicionalmente fueron probadas otras técnicas, como es la separación magnética para mejorar la calidad de los productos reciclados. En vista de los buenos resultados de la investigación, se procede a escalar los ensayos con equipo piloto y distintas composiciones de naturaleza cerámica y hormigón. El equipo utilizado fue un jig de 3´x 1´ en el que se ensayaron las tres muestras con resultados diferentes. La limpieza de los materiales impropios y el yeso fue positiva en las tres muestras, y únicamente la separación entre sí de los componentes pétreos, resultó dependiente de su proporción en la mezcla, obteniéndose los mejores resultados en las muestras con menor cantidad de materiales cerámicos. Finalmente, se procede a analizar en un laboratorio reconocido las propiedades de los áridos reciclados obtenidos en la separación hidráulica por jig, y constatar las mejoras conseguidas para su utilización como materiales de construcción en usos ligados y no ligados. Todo lo anterior permite afirmar que los equipos de separación hidráulica con aceleración diferencial (jig) presentan una innovación tecnológica en el reciclado de los residuos de construcción y demolición (RCD). ABSTRACT The doctoral thesis “Technological Improvements in Recycling of Construction and Demolition Waste (C&DW)” researches the hydraulic separators utilization in order to improve the recycled aggregates quality, demonstrating that the equipment is more efficient than the current techniques based on the simple density separation. This doctoral thesis has been initially done reviewing the situation of the sector and focusing afterwards on the separation systems used at the Spanish recovery facilities. Once analyzed these and, particularly, the hydraulic type ones, from which a comparative study has been summarized, the behavior of a differential acceleration hydraulic separator with various materials coming from three recycling plants has been tested at laboratory scale. Additionally other techniques have been tested, such as the magnetic separation to improve the quality of recycled products. In view of the good investigation results, the testing process scaled up by using pilot equipment and different ceramics and concrete compositions. The equipment utilized was a jig 3” x 1”, in which the three samples were tested with different results. The unsuitable materials and gypsum cleanliness was positive on the three samples and only the separation among the stony components turned out to be dependent of its proportion in the mixing, obtaining the best results in the samples with less quantity of ceramic materials. Finally, the properties of the recycled aggregates obtained by jig hydraulic separation are analyzed at a recognized laboratory and the improvements gained for their utilization as construction materials, in bounded and unbounded uses, are stated. The facts cited are a basis for affirming that the hydraulic separator equipments with differential acceleration (jig) offer a technological innovation in the Recycling of Construction and Demolition Waste (C&DW).

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The dynamic effects of high-speed trains on viaducts are important issues for the design of the structures, as well as for the consideration of safe running conditions for the trains. In this work we start by reviewing the relevance of some basic design aspects. The significance of impact factor envelopes for moving loads is considered first. Resonance which may be achieved for high-speed trains requires dynamic analysis, for which some key aspects are discussed. The relevance of performing a longitudinal distribution of axle loads, the number of modes taken in analysis, and the consideration of vehicle-structure interaction are discussed with representative examples. The lateral dynamic effects of running trains on bridges is of importance for laterally compliant viaducts, such as some very tall structures erected in new high-speed lines. The relevance of this study is mainly for the safety of the traffic, considering both internal actions such as the hunting motion as well as external actions such as wind or earthquakes [1]. These studies require three-dimensional dynamic coupled vehicle-bridge models, and consideration of wheel to rail contact, a phenomenon which is complex and costly to model in detail. We describe here a fully nonlinear coupled model, described in absolute coordinates and incorporated into a commercial finite element framework [2]. The wheel-rail contact has been considered using a FastSim algorithm which provides a compromise between accuracy and computational cost, and captures the main nonlinear response of the contact interface. Two applications are presented, firstly to a vehicle subject to a strong wind gust traversing a bridge, showing the relevance of the nonlinear wheel-rail contact model as well as the dynamic interaction between bridge and vehicle. The second application is to a real HS viaduct with a long continuous deck and tall piers and high lateral compliance [3]. The results show the safety of the traffic as well as the importance of considering features such as track alignment irregularities.

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The dynamic effects of high-speed trains on viaducts are important issues for the design of the structures, as well as for determining safe running conditions of trains. In this work we start by reviewing the relevance of some basic moving load models for the dynamic action of vertical traffic loads. The study of lateral dynamics of running trains on bridges is of importance mainly for the safety of the traffic, and may be relevant for laterally compliant bridges. These studies require 3D coupled vehicle-bridge models and consideration of wheel to rail contact. We describe here a fully nonlinear coupled model, formulated in absolute coordinates and incorporated into a commercial finite element framework. An application example is presented for a vehicle subject to a strong wind gust traversing a bridge, showing the relevance of the nonlinear wheel-rail contact model as well as the interaction between bridge and vehicle.

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En este proyecto se analizan las características y el ciclo de diseño asociado al entorno de CAD IspLEVER, de Lattice Semiconductor, con la finalidad de evaluar su adecuación a la docencia relacionada con la ingeniería de sistemas digitales cableados. En base a este estudio se realiza una guía del manejo de las diferentes herramientas que se integran en el entorno. Además, se realiza la caracterización de una serie de familias de dispositivos del fabricante Lattice Semiconductor que pudiera servir de apoyo a la hora de elegir un dispositivo de este fabricante para la realización de un determinado diseño. Para dar comienzo a la realización del estudio del entorno y de las herramientas que integra IspLEVER, se procedió a la familiarización con el marco de trabajo. Esta familiarización se realizó, en un principio, a través de la lectura de la documentación ofrecida por el fabricante en su página web, http://www.latticesemi.com. Tras esta lectura, que sirvió para tener una primera visión de las características de la herramienta, se procedió a la descarga del paquete de instalación; el fabricante ofrece una versión de evaluación que expira a los 12 meses. Una vez descargado, se instaló y para terminar con los preparativos, se pasó el procedimiento de obtención de la licencia. Con ello se consiguió tener el software preparado para su utilización. A continuación se emplearon horas de trabajo para, sin documentación alguna, tratar de crear diseños; con este trabajo se pretendía detectar lo intuitivo que resulta el entorno cuando se tienen conocimientos de herramientas de CAD electrónico. Tras esta primera toma de contacto con el entorno real, se procedió al estudio de las diferentes opciones que ofrece para la realización de diseños, ya sean lógicos o físicos. Además del estudio de todas las posibilidades que ofrece el entorno, el trabajo se focalizó en la detección y comparación de las distintas opciones que ofrece para realizar una misma tarea, como ocurre con la asignación de pines o con la revisión de los resultados de una simulación, entre otras. Entrelazado con el estudio de las opciones que ofrece el entorno, se realizó el estudio de las distintas herramientas de trabajo integradas en el mismo. Una vez estudiado el entorno y las herramientas, se procedió a la realización del tutorial. Se capturaron todas las imágenes que se consideraron apropiadas para que al alumno le resultase cómodo y fácil seguir todas las indicaciones que el tutorial ofrece, para la realización de un ciclo de diseño lógico completo. Tras la realización del tutorial, se procedió a revisar la amplia documentación que el fabricante ofrece de cada una de las distintas familias de dispositivos que fabrica. El fin de esta revisión no fue otro que realizar una caracterización de las distintas familias, que pudiera servir de apoyo a la hora de elegir un dispositivo de este fabricante para la realización de un determinado diseño. Este estudio de las familias de dispositivos del fabricante, también se realizó para detectar qué familia de dispositivos era la más idónea para incluir uno de sus miembros en una hipotética placa de prototipado, para la realización de prácticas de laboratorio. ABSTRACT. This project consists in the analysis of the characteristics and the design cycle associated with the IspLEVER environment of CAD, by Lattice Semiconductor. The objective of that analysis is to evaluate their suitability for teaching engineering related to wired digital systems. Based on this analysis a guide was made for managing the different tools that are integrated into the environment. In addition, the characterization of several families by the manufacturer Lattice Semiconductor was made, with the objective that it could be used to support the choice of a Lattice’s device to perform a certain design. To start the IspLEVER environment and tools study, I began with a familiarization with the environment. This familiarization consisted in a study of the manufacturer documentation offered in their web page, http://www.latticesemi.com. After that, I had a general view about the characteristics of the environment and environment tools. Then I continued downloading the installation package. The manufacturer offers an evaluation version that expires in the period of one year. After that download, the environment was installed. Finally, the licensing procedure was followed to finish with the preparations. Then, the software was prepared for its utilization. Following, several work hours were wasted without documentation, trying to create designs. This work has been to identify how intuitive the environment is when you have knowledge of electronic CAD tools. After this first point of contact with the real environment, I proceeded to study different offered options, by the manufacturer, for the realization of either logical or physical designs. In addition to studying all the possibilities offered by the environment, the work is focused on the detection and comparison of the various options offered to perform the same task, as with the pin assignment or reviewing the results of a simulation… At the same time, the environment tools were studied. At this point, I began creating the tutorial. I captured all the figures that I consider important to make it easy to the students. The tutorial contains a complete logical design cycle. When the tutorial was finished, I started to review the manufacturer documentation about each devices family. The purpose of this review was to characterize the different families to support the device selection in future designs. Another purpose of that characterization was focused on the detection of the best family to include one of its members in a prototyping board for conducting laboratory practices.

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En la vida cotidiana, los errores no solo se reconocen, sino que también nos plantean nuevas situaciones. En la “filosofía de la ciencia” se han tratado como un factor determinante para la definición y la crítica de la propia ciencia. Se pretende que a través de la solución del “problema filosófico del error” de Víctor Brochard, y de algunos episodios claves de la epistemología, reconozcamos “el error” dentro de los procesos arquitectónicos como un factor crítico y productivo en sí mismo. ABSTRACT: In everyday life, errors are not only acknowledged, but they also expose us to new situations. In the field of philosophy of science, errors have been viewed as an important factor for determining and reviewing the definition of science itself. This article proposes that: through Victor Brochard´s solution of “the philosophical problem of error” and through some key aspects in epistemology, we will be able to determine that architectural “errors” can provide us with reflective and productive insights in architecture.

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Descripción de ciertos rasgos geológicos que amenazan el patrimonio religioso rupestre español. Rock sanctuaries are a historical heritage not as well-known as other religious constructions, due to their usual recondite location and abandoned condition. Spain has a large number of examples, mostly excavated during the Early Middle Age or even before. Fortunately, some of them are used on present worship, but the majority of these ancient shrines have suffered of severe damage through time, mostly due to common geological patterns. Some others threaten to collapse soon unless urgent remedial improvement is applied. Some examples at different locations are shown, reviewing their problems, which involve weathering, major rock cracks, soft rock pillars and others related to the defective site where they were located.

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Glutens, the storage proteins in wheat grains, are a major source of protein in human nutrition. The protein composition of wheat has therefore been an important focus of cereal research. Proteomic tools have been used to describe the genetic diversity of wheat germplasms from different origins at the level of polymorphisms in alleles encoding glutenin and gliadin, the two main proteins of gluten. More recently, proteomics has been used to understand the impact of specific gluten proteins on wheat quality. Here we review the impact of proteomics on the study of gluten proteins as it has evolved from fractionation and electrophoretic techniques to advanced mass spectrometry. In the postgenome era, proteomics is proving to be essential in the effort to identify and understand the interactions between different gluten proteins. This is helping to fill in gaps in our knowledge of how the technological quality of wheat is determined by the interaction between genotype and environment. We also collate information on the various storage protein alleles identified and their prevalence, which makes it possible to infer the effects of wheat selection on grain protein content. We conclude by reviewing the more recent use of transgenesis aimed at improving the quality of gluten.