991 resultados para Software CAD 3D para vestu


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In this paper we present a model-based approach for real-time camera pose estimation in industrial scenarios. The line model which is used for tracking is generated by rendering a polygonal model and extracting contours out of the rendered scene. By un-projecting a point on the contour with the depth value stored in the z-buffer, the 3D coordinates of the contour can be calculated. For establishing 2D/3D correspondences the 3D control points on the contour are projected into the image and a perpendicular search for gradient maxima for every point on the contour is performed. Multiple hypotheses of 2D image points corresponding to a 3D control point make the pose estimation robust against ambiguous edges in the image.

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Recently, stable markerless 6 DOF video based handtracking devices became available. These devices simultaneously track the positions and orientations of both user hands in different postures with at least 25 frames per second. Such hand-tracking allows for using the human hands as natural input devices. However, the absence of physical buttons for performing click actions and state changes poses severe challenges in designing an efficient and easy to use 3D interface on top of such a device. In particular, for coupling and decoupling a virtual object’s movements to the user’s hand (i.e. grabbing and releasing) a solution has to be found. In this paper, we introduce a novel technique for efficient two-handed grabbing and releasing objects and intuitively manipulating them in the virtual space. This technique is integrated in a novel 3D interface for virtual manipulations. A user experiment shows the superior applicability of this new technique. Last but not least, we describe how this technique can be exploited in practice to improve interaction by integrating it with RTT DeltaGen, a professional CAD/CAS visualization and editing tool.

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Design rights represent an interesting example of how the EU legislature has successfully regulated an otherwise heterogeneous field of law. Yet this type of protection is not for all. The tools created by EU intervention have been drafted paying much more attention to the industry sector rather than to designers themselves. In particular, modern, digitally based, individual or small-sized, 3D printing, open designers and their needs are largely neglected by such legislation. There is obviously nothing wrong in drafting legal tools around the needs of an industrial sector with an important role in the EU economy, on the contrary, this is a legitimate and good decision of industrial policy. However, good legislation should be fair, balanced, and (technologically) neutral in order to offer suitable solutions to all the players in the market, and all the citizens in the society, without discriminating the smallest or the newest: the cost would be to stifle innovation. The use of printing machinery to manufacture physical objects created digitally thanks to computer programs such as Computer-Aided Design (CAD) software has been in place for quite a few years, and it is actually the standard in many industrial fields, from aeronautics to home furniture. The change in recent years that has the potential to be a paradigm-shifting factor is a combination between the opularization of such technologies (price, size, usability, quality) and the diffusion of a culture based on access to and reuse of knowledge. We will call this blend Open Design. It is probably still too early, however, to say whether 3D printing will be used in the future to refer to a major event in human history, or instead will be relegated to a lonely Wikipedia entry similarly to ³Betamax² (copyright scholars are familiar with it for other reasons). It is not too early, however, to develop a legal analysis that will hopefully contribute to clarifying the major issues found in current EU design law structure, why many modern open designers will probably find better protection in copyright, and whether they can successfully rely on open licenses to achieve their goals. With regard to the latter point, we will use Creative Commons (CC) licenses to test our hypothesis due to their unique characteristic to be modular, i.e. to have different license elements (clauses) that licensors can choose in order to adapt the license to their own needs.”

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In this paper we follow a theory-based approach to study the assimilation of compliance software in highly regulated multinational enterprises. These relatively new software products support the automation of controls which are associated with mandatory compliance requirements. We use institutional and success factor theories to explain the assimilation of compliance software. A framework for analyzing the assimilation of Access Control Systems (ACS), a special type of compliance software, is developed and used to reflect the experiences obtained in four in-depth case studies. One result is that coercive, mimetic, and normative pressures significantly effect ACS assimilation. On the other hand, quality aspects have only a moderate impact at the beginning of the assimilation process, in later phases the impact may increase if performance and improvement objectives become more relevant. In addition, it turns out that position of the enterprises and compatibility heavily influence the assimilation process.

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PURPOSE The purpose of this study was to identify morphologic factors affecting type I endoleak formation and bird-beak configuration after thoracic endovascular aortic repair (TEVAR). METHODS Computed tomography (CT) data of 57 patients (40 males; median age, 66 years) undergoing TEVAR for thoracic aortic aneurysm (34 TAA, 19 TAAA) or penetrating aortic ulcer (n = 4) between 2001 and 2010 were retrospectively reviewed. In 28 patients, the Gore TAG® stent-graft was used, followed by the Medtronic Valiant® in 16 cases, the Medtronic Talent® in 8, and the Cook Zenith® in 5 cases. Proximal landing zone (PLZ) was in zone 1 in 13, zone 2 in 13, zone 3 in 23, and zone 4 in 8 patients. In 14 patients (25%), the procedure was urgent or emergent. In each case, pre- and postoperative CT angiography was analyzed using a dedicated image processing workstation and complimentary in-house developed software based on a 3D cylindrical intensity model to calculate aortic arch angulation and conicity of the landing zones (LZ). RESULTS Primary type Ia endoleak rate was 12% (7/57) and subsequent re-intervention rate was 86% (6/7). Left subclavian artery (LSA) coverage (p = 0.036) and conicity of the PLZ (5.9 vs. 2.6 mm; p = 0.016) were significantly associated with an increased type Ia endoleak rate. Bird-beak configuration was observed in 16 patients (28%) and was associated with a smaller radius of the aortic arch curvature (42 vs. 65 mm; p = 0.049). Type Ia endoleak was not associated with a bird-beak configuration (p = 0.388). Primary type Ib endoleak rate was 7% (4/57) and subsequent re-intervention rate was 100%. Conicity of the distal LZ was associated with an increased type Ib endoleak rate (8.3 vs. 2.6 mm; p = 0.038). CONCLUSIONS CT-based 3D aortic morphometry helps to identify risk factors of type I endoleak formation and bird-beak configuration during TEVAR. These factors were LSA coverage and conicity within the landing zones for type I endoleak formation and steep aortic angulation for bird-beak configuration.

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PURPOSE The study aims to evaluate three-dimensionally (3D) the accuracy of implant impressions using a new resin splinting material, "Smart Dentin Replacement" (SDR). MATERIALS AND METHODS A titanium model of an edentulous mandible with six implant analogues was used as a master model and its dimensions measured with a coordinate measuring machine. Before the total 60 impressions were taken (open tray, screw-retained abutments, vinyl polysiloxane), they were divided in four groups: A (test): copings pick-up splinted with dental floss and fotopolymerizing SDR; B (test): see A, additionally sectioned and splinted again with SDR; C (control): copings pick-up splinted with dental floss and autopolymerizing Duralay® (Reliance Dental Mfg. Co., Alsip, IL, USA) acrylic resin; and D (control): see C, additionally sectioned and splinted again with Duralay. The impressions were measured directly with an optomechanical coordinate measuring machine and analyzed with a computer-aided design (CAD) geometric modeling software. The Wilcoxon matched-pair signed-rank test was used to compare groups. RESULTS While there was no difference (p = .430) between the mean 3D deviations of the test groups A (17.5 μm) and B (17.4 μm), they both showed statistically significant differences (p < .003) compared with both control groups (C 25.0 μm, D 19.1 μm). CONCLUSIONS Conventional impression techniques for edentulous jaws with multiple implants are highly accurate using the new fotopolymerizing splinting material SDR. Sectioning and rejoining of the SDR splinting had no impact on the impression accuracy.

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BACKGROUND The aim of this study was to evaluate the accuracy of linear measurements on three imaging modalities: lateral cephalograms from a cephalometric machine with a 3 m source-to-mid-sagittal-plane distance (SMD), from a machine with 1.5 m SMD and 3D models from cone-beam computed tomography (CBCT) data. METHODS Twenty-one dry human skulls were used. Lateral cephalograms were taken, using two cephalometric devices: one with a 3 m SMD and one with a 1.5 m SMD. CBCT scans were taken by 3D Accuitomo® 170, and 3D surface models were created in Maxilim® software. Thirteen linear measurements were completed twice by two observers with a 4 week interval. Direct physical measurements by a digital calliper were defined as the gold standard. Statistical analysis was performed. RESULTS Nasion-Point A was significantly different from the gold standard in all methods. More statistically significant differences were found on the measurements of the 3 m SMD cephalograms in comparison to the other methods. Intra- and inter-observer agreement based on 3D measurements was slightly better than others. LIMITATIONS Dry human skulls without soft tissues were used. Therefore, the results have to be interpreted with caution, as they do not fully represent clinical conditions. CONCLUSIONS 3D measurements resulted in a better observer agreement. The accuracy of the measurements based on CBCT and 1.5 m SMD cephalogram was better than a 3 m SMD cephalogram. These findings demonstrated the linear measurements accuracy and reliability of 3D measurements based on CBCT data when compared to 2D techniques. Future studies should focus on the implementation of 3D cephalometry in clinical practice.

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This paper presents the development history and specification of a 3D game engine titled "Spark Engine". The term "engine" is used to describe a complex graphics software suite that streamlines application development and provides efficient rendering functionality. A game engine specifically provides tools to simplify game development. Spark Engine is fully shader driven and is built on top of Microsoft's XNA Framework. It is a reusable and flexible platform that can be used to build any type of graphics application ranging from gaming to simulation. The engine was released as open source software under the New BSD License with an interest in furthering its development.

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With continuous new improvements in brachytherapy source designs and techniques, method of 3D dosimetry for treatment dose verifications would better ensure accurate patient radiotherapy treatment. This study was aimed to first evaluate the 3D dose distributions of the low-dose rate (LDR) Amersham 6711 OncoseedTM using PRESAGE® dosimeters to establish PRESAGE® as a suitable brachytherapy dosimeter. The new AgX100 125I seed model (Theragenics Corporation) was then characterized using PRESAGE® following the TG-43 protocol. PRESAGE® dosimeters are solid, polyurethane-based, 3D dosimeters doped with radiochromic leuco dyes that produce a linear optical density response to radiation dose. For this project, the radiochromic response in PRESAGE® was captured using optical-CT scanning (632 nm) and the final 3D dose matrix was reconstructed using the MATLAB software. An Amersham 6711 seed with an air-kerma strength of approximately 9 U was used to irradiate two dosimeters to 2 Gy and 11 Gy at 1 cm to evaluate dose rates in the r=1 cm to r=5 cm region. The dosimetry parameters were compared to the values published in the updated AAPM Report No. 51 (TG-43U1). An AgX100 seed with an air-kerma strength of about 6 U was used to irradiate two dosimeters to 3.6 Gy and 12.5 Gy at 1 cm. The dosimetry parameters for the AgX100 were compared to the values measured from previous Monte-Carlo and experimental studies. In general, the measured dose rate constant, anisotropy function, and radial dose function for the Amersham 6711 showed agreements better than 5% compared to consensus values in the r=1 to r=3 cm region. The dose rates and radial dose functions measured for the AgX100 agreed with the MCNPX and TLD-measured values within 3% in the r=1 to r=3 cm region. The measured anisotropy function in PRESAGE® showed relative differences of up to 9% with the MCNPX calculated values. It was determined that post-irradiation optical density change over several days was non-linear in different dose regions, and therefore the dose values in the r=4 to r=5 cm regions had higher uncertainty due to this effect. This study demonstrated that within the radial distance of 3 cm, brachytherapy dosimetry in PRESAGE® can be accurate within 5% as long as irradiation times are within 48 hours.

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The ability to view and interact with 3D models has been happening for a long time. However, vision-based 3D modeling has only seen limited success in applications, as it faces many technical challenges. Hand-held mobile devices have changed the way we interact with virtual reality environments. Their high mobility and technical features, such as inertial sensors, cameras and fast processors, are especially attractive for advancing the state of the art in virtual reality systems. Also, their ubiquity and fast Internet connection open a path to distributed and collaborative development. However, such path has not been fully explored in many domains. VR systems for real world engineering contexts are still difficult to use, especially when geographically dispersed engineering teams need to collaboratively visualize and review 3D CAD models. Another challenge is the ability to rendering these environments at the required interactive rates and with high fidelity. In this document it is presented a virtual reality system mobile for visualization, navigation and reviewing large scale 3D CAD models, held under the CEDAR (Collaborative Engineering Design and Review) project. It’s focused on interaction using different navigation modes. The system uses the mobile device's inertial sensors and camera to allow users to navigate through large scale models. IT professionals, architects, civil engineers and oil industry experts were involved in a qualitative assessment of the CEDAR system, in the form of direct user interaction with the prototypes and audio-recorded interviews about the prototypes. The lessons learned are valuable and are presented on this document. Subsequently it was prepared a quantitative study on the different navigation modes to analyze the best mode to use it in a given situation.

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Una alta productividad en Ingeniería está asociada entre otras cosas a una gestión eficiente del flujo de las enormes cantidades de información y correspondientes tomas de decisiones consubstanciales a los entornos de diseño y producción. Ello exige que nuestros titulados estén formados para ser capaces de manejar esa información de modo integrado, a través de los diferentes estadios en que se genera y procesa. En el contexto de la enseñanza de la Ingeniería existen un buen número de cursos designados a desarrollar competencias específicas, como las requeridas en los currículos académicos, pero muy pocos en los cuales las competencias de integración sean el objetivo principal. En este artículo se documenta una asignatura que tiene esa orientación, con la intención de alimentar el debate sobre la formación, tan necesario en tiempos de fuerte contracción de la actividad económica como el que vivimos en la actualidad y que está promoviendo el COIN. La asignatura se denomina “Tecnologías de la Información Aplicadas a la Construcción Naval” y es impartida en la titulación de Ingeniero Naval y Oceánico, plan 2002, de la Universidad Politécnica de Madrid (UPM). La primera parte de la asignatura está dedicada a la planificación y gestión de proyectos; los estudiantes adquieren competencias en la definición, usando Ms-PROJECT, de la estructura de descomposición de tareas y la asignación de recursos así como en el seguimiento de proyectos, a través de una serie de ejemplos de complejidad creciente, finalizando con la construcción de un buque. La segunda parte está dedicada al uso de un gestor de bases de datos, Ms-ACCESS, y orientada a la gestión de la información relativa a Producción. Otra vez la estrategia pasa por trabajar sobre una serie de ejemplos de complejidad creciente y se finaliza con la administración de una base de datos de tuberías de un buque, para las cuales se establecen hitos de producción, recepción y montaje, lo que conecta está parte con la primera. Finalmente, la tercera parte de la asignatura está dedicada al trabajo con FORAN, con el cual se definen con detalle los elementos estructurales de todo el buque sobre el que se ha elaborado la planificación. En esta parte, el trabajo es cooperativo, dado que los estudiantes operan simultáneamente en el mismo modelo 3D. Las clases se realizan en un aula multimedia en la cual cada estudiante puede utilizar todas las aplicaciones de software tratadas. Se han realizado encuestas a los estudiantes para obtener una retroalimentación desde su experiencia así como para hacer una valoración de su satisfacción con el proceso de aprendizaje. Los resultados de esas encuestas son discutidos en el artículo.

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Las prácticas en laboratorios forman una parte muy importante de la formación en todos los programas docentes. A pesar de esta importancia, la creación de un laboratorio no es una tarea fácil, ya que el hecho de equipar un laboratorio puede suponer un gran gasto económico, tanto inicial como posterior. Como solución, surge la educación a distancia, y en concreto los laboratorios virtuales, es decir, simulaciones de un laboratorio real utilizando modelos matemáticos. Por sus características y flexibilidad se han ido desarrollando laboratorios virtuales en el ámbito docente, pero no todas las áreas cuentan con tantas posibilidades o facilidades como en la electrónica. La mayoría de los laboratorios accesibles desde Internet que hay en la actualidad dentro de la enseñanza a distancia o formación online, son virtuales. El laboratorio que se ha desarrollado tiene como principal ventaja la realización de prácticas controlando instrumentos y circuitos reales de forma remota. El proyecto consiste en realizar un sistema software para implementar un laboratorio remoto en el área de la electrónica analógica, que pueda ser utilizado como complemento a las actividades formativas que se realizan en los laboratorios de los centros de enseñanza. El sistema completo también consta de un hardware controlado mediante buses de comunicación estándar, que permite la implementación de distintos circuitos analógicos, de tal forma que se pueda realizar prácticas sobre circuitos físicos reales. Para desarrollar un laboratorio lo más real posible, la aplicación que maneja el estudiante es un visor 3D. Con la utilización de un visor 3D lo que se pretende es tener un aumento de la realidad a la hora de realizar las prácticas de laboratorio remotamente. El sistema desarrollado cuenta con un sistema de comunicación basado en un modelo cliente-servidor: • Servidor: se encarga de procesar las acciones que realiza el cliente y controla y monitoriza los instrumentos y dispositivos del sistema hardware. • Cliente: sería el usuario final, que mediante un visor 3D comunica las acciones a realizar al servidor para que éste las procese. Practices in laboratories are a very important part of training in all educational programs. Despite this importance, the establishment of a laboratory is not an easy task, since the fact of equipping a laboratory can be a great economic budget, both initial and subsequent spending. As a solution, appears the education at distance (online), and in particular the virtual labs, namely simulations of a real laboratory by using mathematical models. Virtual laboratories in the field of teaching have been developed for its features and flexibility, but not all areas have so many possibilities or facilities as in electronics. The most accessible laboratories from the Internet that are currently accessible within the distance or e-learning (on-line) are virtual. The laboratory which has been developed has as a main advantage to make practices or exercises in the fact of controlling instruments and real circuits remotely. The project consists of making a software system in order to implement a remote laboratory in the area of analog electronics that can be used as a complement to the others training activities to be carried out. The complete system also consists of a controlled hardware by standard communication buses that allow the implementation of several analog circuits, in such a way that practices can control real physical circuits. To develop a laboratory as more realistic as possible, the application that manages the student is a 3D viewer. With the use of a 3D viewer, is intended to have an increase in reality when any student wants to access to laboratory practices remotely. The developed system has a communication system based on a model Client/Server: • Server: The system that handles actions provided by the client and controls and monitors the instruments and devices in the hardware system. • Client: The end user, which using a 3D viewer, communicates the actions to be performed at the server so that it will process them.

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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 este proyecto se ha desarrollado un código de MATLAB para el procesamiento de imágenes tomográficas 3D, de muestras de asfalto de carreteras en Polonia. Estas imágenes en 3D han sido tomadas por un equipo de investigación de la Universidad Tecnológica de Lodz (LUT). El objetivo de este proyecto es crear una herramienta que se pueda utilizar para estudiar las diferentes muestras de asfalto 3D y pueda servir para estudiar las pruebas de estrés que experimentan las muestras en el laboratorio. Con el objetivo final de encontrar soluciones a la degradación sufrida en las carreteras de Polonia, debido a diferentes causas, como son las condiciones meteorológicas. La degradación de las carreteras es un tema que se ha investigado desde hace muchos años, debido a la fuerte degradación causada por diferentes factores como son climáticos, la falta de mantenimiento o el tráfico excesivo en algunos casos. Es en Polonia, donde estos tres factores hacen que la composición de muchas carreteras se degrade rápidamente, sobre todo debido a las condiciones meteorológicas sufridas a lo largo del año, con temperaturas que van desde 30° C en verano a -20° C en invierno. Esto hace que la composición de las carreteras sufra mucho y el asfalto se levante, lo que aumenta los costos de mantenimiento y los accidentes de carretera. Este proyecto parte de la base de investigación que se lleva a cabo en la LUT, tratando de mejorar el análisis de las muestras de asfalto, por lo que se realizarán las pruebas de estrés y encontrar soluciones para mejorar el asfalto en las carreteras polacas. Esto disminuiría notablemente el costo de mantenimiento. A pesar de no entrar en aspectos muy técnicos sobre el asfalto y su composición, se ha necesitado realizar un estudio profundo sobre todas sus características, para crear un código capaz de obtener los mejores resultados. Por estas razones, se ha desarrollado en Matlab, los algoritmos que permiten el estudio de los especímenes 3D de asfalto. Se ha utilizado este software, ya que Matlab es una poderosa herramienta matemática que permite operar con matrices para realización de operaciones rápidamente, permitiendo desarrollar un código específico para el tratamiento y procesamiento de imágenes en 3D. Gracias a esta herramienta, estos algoritmos realizan procesos tales como, la segmentación de la imagen 3D, pre y post procesamiento de la imagen, filtrado o todo tipo de análisis microestructural de las muestras de asfalto que se están estudiando. El código presentado para la segmentación de las muestras de asfalto 3D es menos complejo en su diseño y desarrollo, debido a las herramientas de procesamiento de imágenes que incluye Matlab, que facilitan significativamente la tarea de programación, así como el método de segmentación utilizado. Respecto al código, este ha sido diseñado teniendo en cuenta el objetivo de facilitar el trabajo de análisis y estudio de las imágenes en 3D de las muestras de asfalto. Por lo tanto, el principal objetivo es el de crear una herramienta para el estudio de este código, por ello fue desarrollado para que pueda ser integrado en un entorno visual, de manera que sea más fácil y simple su utilización. Ese es el motivo por el cual todos estos algoritmos y funciones, que ha sido desarrolladas, se integrarán en una herramienta visual que se ha desarrollado con el GUIDE de Matlab. Esta herramienta ha sido creada en colaboración con Jorge Vega, y fue desarrollada en su proyecto final de carrera, cuyo título es: Segmentación microestructural de Imágenes en 3D de la muestra de asfalto utilizando Matlab. En esta herramienta se ha utilizado todo las funciones programadas en este proyecto, y tiene el objetivo de desarrollar una herramienta que permita crear un entorno gráfico intuitivo y de fácil uso para el estudio de las muestras de 3D de asfalto. Este proyecto se ha dividido en 4 capítulos, en un primer lugar estará la introducción, donde se presentarán los aspectos más importante que se va a componer el proyecto. En el segundo capítulo se presentarán todos los datos técnicos que se han tenido que estudiar para desarrollar la herramienta, entre los que cabe los tres temas más importantes que se han estudiado en este proyecto: materiales asfálticos, los principios de la tomografías 3D y el procesamiento de imágenes. Esta será la base para el tercer capítulo, que expondrá la metodología utilizada en la elaboración del código, con la explicación del entorno de trabajo utilizado en Matlab y todas las funciones de procesamiento de imágenes utilizadas. Además, se muestra todo el código desarrollado, así como una descripción teórica de los métodos utilizados para el pre-procesamiento y segmentación de las imagenes en 3D. En el capítulo 4, se mostrarán los resultados obtenidos en el estudio de una de las muestras de asfalto, y, finalmente, el último capítulo se basa en las conclusiones sobre el desarrollo de este proyecto. En este proyecto se ha llevado han realizado todos los puntos que se establecieron como punto de partida en el anteproyecto para crear la herramienta, a pesar de que se ha dejado para futuros proyectos nuevas posibilidades de este codigo, como por ejemplo, la detección automática de las diferentes regiones de una muestra de asfalto debido a su composición. Como se muestra en este proyecto, las técnicas de procesamiento de imágenes se utilizan cada vez más en multitud áreas, como pueden ser industriales o médicas. En consecuencia, este tipo de proyecto tiene multitud de posibilidades, y pudiendo ser la base para muchas nuevas aplicaciones que se puedan desarrollar en un futuro. Por último, se concluye que este proyecto ha contribuido a fortalecer las habilidades de programación, ampliando el conocimiento de Matlab y de la teoría de procesamiento de imágenes. Del mismo modo, este trabajo proporciona una base para el desarrollo de un proyecto más amplio cuyo alcance será una herramienta que puedas ser utilizada por el equipo de investigación de la Universidad Tecnológica de Lodz y en futuros proyectos. ABSTRACT In this project has been developed one code in MATLAB to process X-ray tomographic 3D images of asphalt specimens. These images 3D has been taken by a research team of the Lodz University of Technology (LUT). The aim of this project is to create a tool that can be used to study differents asphalt specimen and can be used to study them after stress tests undergoing the samples. With the final goal to find solutions to the degradation suffered roads in Poland due to differents causes, like weather conditions. The degradation of the roads is an issue that has been investigated many years ago, due to strong degradation suffered caused by various factors such as climate, poor maintenance or excessive traffic in some cases. It is in Poland where these three factors make the composition of many roads degrade rapidly, especially due to the weather conditions suffered along the year, with temperatures ranging from 30 o C in summer to -20 ° C in winter. This causes the roads suffers a lot and asphalt rises shortly after putting, increasing maintenance costs and road accident. This project part of the base that research is taking place at the LUT, in order to better analyze the asphalt specimens, they are tested for stress and find solutions to improve the asphalt on Polish roads. This would decrease remarkable maintenance cost. Although this project will not go into the technical aspect as asphalt and composition, but it has been required a deep study about all of its features, to create a code able to obtain the best results. For these reasons, there have been developed in Matlab, algorithms that allow the study of 3D specimens of asphalt. Matlab is a powerful mathematical tool, which allows arrays operate fastly, allowing to develop specific code for the treatment and processing of 3D images. Thus, these algorithms perform processes such as the multidimensional matrix sgementation, pre and post processing with the same filtering algorithms or microstructural analysis of asphalt specimen which being studied. All these algorithms and function that has been developed to be integrated into a visual tool which it be developed with the GUIDE of Matlab. This tool has been created in the project of Jorge Vega which name is: Microstructural segmentation of 3D images of asphalt specimen using Matlab engine. In this tool it has been used all the functions programmed in this project, and it has the aim to develop an easy and intuitive graphical environment for the study of 3D samples of asphalt. This project has been divided into 4 chapters plus the introduction, the second chapter introduces the state-of-the-art of the three of the most important topics that have been studied in this project: asphalt materials, principle of X-ray tomography and image processing. This will be the base for the third chapter, which will outline the methodology used in developing the code, explaining the working environment of Matlab and all the functions of processing images used. In addition, it will be shown all the developed code created, as well as a theoretical description of the methods used for preprocessing and 3D image segmentation. In Chapter 4 is shown the results obtained from the study of one of the specimens of asphalt, and finally the last chapter draws the conclusions regarding the development of this project.

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El objetivo principal de esta tesis es el desarrollo de herramientas numéricas basadas en técnicas de onda completa para el diseño asistido por ordenador (Computer-Aided Design,‘CAD’) de dispositivos de microondas. En este contexto, se desarrolla una herramienta numérica basada en el método de los elementos finitos para el diseño y análisis de antenas impresas mediante algoritmos de optimización. Esta técnica consiste en dividir el análisis de una antena en dos partes. Una parte de análisis 3D que se realiza sólo una vez en cada punto de frecuencia de la banda de funcionamiento donde se sustituye una superficie que contiene la metalización del parche por puertas artificiales. En una segunda parte se inserta entre las puertas artificiales en la estructura 3D la superficie soportando una metalización y se procede un análisis 2D para caracterizar el comportamiento de la antena. La técnica propuesta en esta tesis se puede implementar en un algoritmo de optimización para definir el perfil de la antena que permite conseguir los objetivos del diseño. Se valida experimentalmente dicha técnica empleándola en el diseño de antenas impresas de banda ancha para diferentes aplicaciones mediante la optimización del perfil de los parches. También, se desarrolla en esta tesis un procedimiento basado en el método de descomposición de dominio y el método de los elementos finitos para el diseño de dispositivos pasivos de microonda. Se utiliza este procedimiento en particular para el diseño y sintonía de filtros de microondas. En la primera etapa de su aplicación se divide la estructura que se quiere analizar en subdominios aplicando el método de descomposición de dominio, este proceso permite analizar cada segmento por separado utilizando el método de análisis adecuado dado que suele haber subdominios que se pueden analizar mediante métodos analíticos por lo que el tiempo de análisis es más reducido. Se utilizan métodos numéricos para analizar los subdominios que no se pueden analizar mediante métodos analíticos. En esta tesis, se utiliza el método de los elementos finitos para llevar a cabo el análisis. Además de la descomposición de dominio, se aplica un proceso de barrido en frecuencia para reducir los tiempos del análisis. Como método de orden reducido se utiliza la técnica de bases reducidas. Se ha utilizado este procedimiento para diseñar y sintonizar varios ejemplos de filtros con el fin de comprobar la validez de dicho procedimiento. Los resultados obtenidos demuestran la utilidad de este procedimiento y confirman su rigurosidad, precisión y eficiencia en el diseño de filtros de microondas. ABSTRACT The main objective of this thesis is the development of numerical tools based on full-wave techniques for computer-aided design ‘CAD’ of microwave devices. In this context, a numerical technique based on the finite element method ‘FEM’ for the design and analysis of printed antennas using optimization algorithms has been developed. The proposed technique consists in dividing the analysis of the antenna in two stages. In the first stage, the regions of the antenna which do not need to be modified during the CAD process are initially characterized only once from their corresponding matrix transfer function (Generalized Admittance matrix, ‘GAM’). The regions which will be modified are defined as artificial ports, precisely the regions which will contain the conducting surfaces of the printed antenna. In a second stage, the contour shape of the conducting surfaces of the printed antenna is iteratively modified in order to achieve a desired electromagnetic performance of the antenna. In this way, a new GAM of the radiating device which takes into account each printed antenna shape is computed after each iteration. The proposed technique can be implemented with a genetic algorithm to achieve the design objectives. This technique is validated experimentally and applied to the design of wideband printed antennas for different applications by optimizing the shape of the radiating device. In addition, a procedure based on the domain decomposition method and the finite element method has been developed for the design of microwave passive devices. In particular, this procedure can be applied to the design and tune of microwave filters. In the first stage of its implementation, the structure to be analyzed is divided into subdomains using the domain decomposition method; this process allows each subdomains can be analyzed separately using suitable analysis method, since there is usually subdomains that can be analyzed by analytical methods so that the time of analysis is reduced. For analyzing the subdomains that cannot be analyzed by analytical methods, we use the numerical methods. In this thesis, the FEM is used to carry out the analysis. Furthermore the decomposition of the domain, a frequency sweep process is applied to reduce analysis times. The reduced order model as the reduced basis technique is used in this procedure. This procedure is applied to the design and tune of several examples of microwave filters in order to check its validity. The obtained results allow concluding the usefulness of this procedure and confirming their thoroughness, accuracy and efficiency for the design of microwave filters.