Aortic morphometry at endograft position as assessed by 3D image analysis affects risk of type I endoleak formation after TEVAR

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.

A total variation discontinuous Galerkin approach for image restoration

The focal point of this paper is to propose and analyze a P 0 discontinuous Galerkin (DG) formulation for image denoising. The scheme is based on a total variation approach which has been applied successfully in previous papers on image processing. The main idea of the new scheme is to model the restoration process in terms of a discrete energy minimization problem and to derive a corresponding DG variational formulation. Furthermore, we will prove that the method exhibits a unique solution and that a natural maximum principle holds. In addition, a number of examples illustrate the effectiveness of the method.

Arte y nuevas tecnolog��as : acerca de la producci��n, modalidades expositivas y diversas aplicaciones de la imagen digital

Se propone la producci��n y posterior an��lisis de obras digitales que presenta una elaboraci��n te��rica-pr��ctica intr��nseca como sustento de las nuevas categor��as y neologismos surgidos dentro del ��mbito art��stico digital. Se estudian distintas aplicaciones, modalidades de creaci��n, exposici��n y transferencia al medio como as�� tambi��n las posibilidades relacionales que surgen entre imagen digital, objeto art��stico y dise��o de productos traspasando las fronteras de campos disciplinares como Arte y Dise��o. La metodolog��a empleada se concentra en enfoques sociol��gicos y semi��tico-pragm��ticos que permiten realizar un an��lisis profundo de las obras digitales en s�� mismas y en relaci��n a los contextos de producci��n, circulaci��n, exposici��n y consumo.

Area-Efficient Linear Regression Architecture for Real-Time Signal Processing on FPGAs

Linear regression is a technique widely used in digital signal processing. It consists on finding the linear function that better fits a given set of samples. This paper proposes different hardware architectures for the implementation of the linear regression method on FPGAs, specially targeting area restrictive systems. It saves area at the cost of constraining the lengths of the input signal to some fixed values. We have implemented the proposed scheme in an Automatic Modulation Classifier, meeting the hard real-time constraints this kind of systems have.

Bio-inspired FPGA Architecture for Self-Calibration of an Image Compression Core based on Wavelet Transforms in Embedded Systems

A generic bio-inspired adaptive architecture for image compression suitable to be implemented in embedded systems is presented. The architecture allows the system to be tuned during its calibration phase. An evolutionary algorithm is responsible of making the system evolve towards the required performance. A prototype has been implemented in a Xilinx Virtex-5 FPGA featuring an adaptive wavelet transform core directed at improving image compression for specific types of images. An Evolution Strategy has been chosen as the search algorithm and its typical genetic operators adapted to allow for a hardware friendly implementation. HW/SW partitioning issues are also considered after a high level description of the algorithm is profiled which validates the proposed resource allocation in the device fabric. To check the robustness of the system and its adaptation capabilities, different types of images have been selected as validation patterns. A direct application of such a system is its deployment in an unknown environment during design time, letting the calibration phase adjust the system parameters so that it performs efcient image compression. Also, this prototype implementation may serve as an accelerator for the automatic design of evolved transform coefficients which are later on synthesized and implemented in a non-adaptive system in the final implementation device, whether it is a HW or SW based computing device. The architecture has been built in a modular way so that it can be easily extended to adapt other types of image processing cores. Details on this pluggable component point of view are also given in the paper.

A Multiresolution Image Alignment Technique Based on Direct Methods for Pose Estimation of Aerial Vehicles

In this paper, we seek to expand the use of direct methods in real-time applications by proposing a vision-based strategy for pose estimation of aerial vehicles. The vast majority of approaches make use of features to estimate motion. Conversely, the strategy we propose is based on a MR (Multi-Resolution) implementation of an image registration technique (Inverse Compositional Image Alignment ICIA) using direct methods. An on-board camera in a downwards-looking configuration, and the assumption of planar scenes, are the bases of the algorithm. The motion between frames (rotation and translation) is recovered by decomposing the frame-to-frame homography obtained by the ICIA algorithm applied to a patch that covers around the 80% of the image. When the visual estimation is required (e.g. GPS drop-out), this motion is integrated with the previous known estimation of the vehicles' state, obtained from the on-board sensors (GPS/IMU), and the subsequent estimations are based only on the vision-based motion estimations. The proposed strategy is tested with real flight data in representative stages of a flight: cruise, landing, and take-off, being two of those stages considered critical: take-off and landing. The performance of the pose estimation strategy is analyzed by comparing it with the GPS/IMU estimations. Results show correlation between the visual estimation obtained with the MR-ICIA and the GPS/IMU data, that demonstrate that the visual estimation can be used to provide a good approximation of the vehicle's state when it is required (e.g. GPS drop-outs). In terms of performance, the proposed strategy is able to maintain an estimation of the vehicle's state for more than one minute, at real-time frame rates based, only on visual information.

Image sub-segmentation by PFCM and Artificial Neural Networks to detect pore space in 2D and 3D CT soil images

The image by Computed Tomography is a non-invasive alternative for observing soil structures, mainly pore space. The pore space correspond in soil data to empty or free space in the sense that no material is present there but only fluids, the fluid transport depend of pore spaces in soil, for this reason is important identify the regions that correspond to pore zones. In this paper we present a methodology in order to detect pore space and solid soil based on the synergy of the image processing, pattern recognition and artificial intelligence. The mathematical morphology is an image processing technique used for the purpose of image enhancement. In order to find pixels groups with a similar gray level intensity, or more or less homogeneous groups, a novel image sub-segmentation based on a Possibilistic Fuzzy c-Means (PFCM) clustering algorithm was used. The Artificial Neural Networks (ANNs) are very efficient for demanding large scale and generic pattern recognition applications for this reason finally a classifier based on artificial neural network is applied in order to classify soil images in two classes, pore space and solid soil respectively.

An image segmentation based on a genetic algorithm for determining soil coverage by crop residues

Determination of the soil coverage by crop residues after ploughing is a fundamental element of Conservation Agriculture. This paper presents the application of genetic algorithms employed during the fine tuning of the segmentation process of a digital image with the aim of automatically quantifying the residue coverage. In other words, the objective is to achieve a segmentation that would permit the discrimination of the texture of the residue so that the output of the segmentation process is a binary image in which residue zones are isolated from the rest. The RGB images used come from a sample of images in which sections of terrain were photographed with a conventional camera positioned in zenith orientation atop a tripod. The images were taken outdoors under uncontrolled lighting conditions. Up to 92% similarity was achieved between the images obtained by the segmentation process proposed in this paper and the templates made by an elaborate manual tracing process. In addition to the proposed segmentation procedure and the fine tuning procedure that was developed, a global quantification of the soil coverage by residues for the sampled area was achieved that differed by only 0.85% from the quantification obtained using template images. Moreover, the proposed method does not depend on the type of residue present in the image. The study was conducted at the experimental farm ���El Enc��n��� in Alcal�� de Henares (Madrid, Spain).

T��cnicas de procesado digital de se��al aplicadas a aceler��metros

En este proyecto se estudian y analizan las diferentes t��cnicas de procesado digital de se��al aplicadas a aceler��metros. Se hace uso de una tarjeta de prototipado, basada en DSP, para realizar las diferentes pruebas. El proyecto se basa, principalmente, en realizar filtrado digital en se��ales provenientes de un aceler��metro en concreto, el 1201F, cuyo campo de aplicaci��n es b��sicamente la automoci��n. Una vez estudiadas la teor��a de procesado y las caracter��sticas de los filtros, dise��amos una aplicaci��n bas��ndonos sobre todo en el entorno en el que se desarrollar��a una aplicaci��n de este tipo. A lo largo del dise��o, se explican las diferentes fases: dise��o por ordenador (Matlab), dise��o de los filtros en el DSP (C), pruebas sobre el DSP sin el aceler��metro, calibraci��n del aceler��metro, pruebas finales sobre el aceler��metro... Las herramientas utilizadas son: la plataforma Kit de evaluaci��n 21-161N de Analog Devices (equipado con el entorno de desarrollo Visual DSP 4.5++), el aceler��metro 1201F, el sistema de calibraci��n de aceler��metros CS-18-LF de Spektra y los programas software MATLAB 7.5 y CoolEditPRO 2.0. Se realizan ��nicamente filtros IIR de 2�� orden, de todos los tipos (Butterworth, Chebyshev I y II y El��pticos). Realizamos filtros de banda estrecha, paso-banda y banda eliminada, de varios tipos, dentro del fondo de escala que permite el aceler��metro. Una vez realizadas todas las pruebas, tanto simulaciones como f��sicas, se seleccionan los filtros que presentan un mejor funcionamiento y se analizan para obtener conclusiones. Como se dispone de un entorno adecuado para ello, se combinan los filtros entre s�� de varias maneras, para obtener filtros de mayor orden (estructura paralelo). De esta forma, a partir de filtros paso-banda, podemos obtener otras configuraciones que nos dar��n mayor flexibilidad. El objetivo de este proyecto no se basa s��lo en obtener buenos resultados en el filtrado, sino tambi��n de aprovechar las facilidades del entorno y las herramientas de las que disponemos para realizar el dise��o m��s eficiente posible. In this project, we study and analize digital signal processing in order to design an accelerometer-based application. We use a hardware card of evaluation, based on DSP, to make different tests. This project is based in design digital filters for an automotion application. The accelerometer type is 1201F. First, we study digital processing theory and main parameters of real filters, to make a design based on the application environment. Along the application, we comment all the different steps: computer design (Matlab), filter design on the DSP (C language), simulation test on the DSP without the accelerometer, accelerometer calibration, final tests on the accelerometer... Hardware and software tools used are: Kit of Evaluation 21-161-N, based on DSP, of Analog Devices (equiped with software development tool Visual DSP 4.5++), 1201-F accelerometer, CS-18-LF calibration system of SPEKTRA and software tools MATLAB 7.5 and CoolEditPRO 2.0. We only perform 2nd orden IIR filters, all-type : Butterworth, Chebyshev I and II and Ellyptics. We perform bandpass and stopband filters, with very narrow band, taking advantage of the accelerometer's full scale. Once all the evidence, both simulations and physical, are finished, filters having better performance and analyzed and selected to draw conclusions. As there is a suitable environment for it, the filters are combined together in different ways to obtain higher order filters (parallel structure). Thus, from band-pass filters, we can obtain many configurations that will give us greater flexibility. The purpose of this project is not only based on good results in filtering, but also to exploit the facilities of the environment and the available tools to make the most efficient design possible.

Desarrollos para la explotaci��n de datos integrados mediante fotogrametr��a y l��ser esc��ner en proyectos de patrimonio arquitect��nico

La presente tesis doctoral describe los desarrollos realizados, y finalmente materializados en patentes con registro de la propiedad intelectual, para la integraci��n de las nuevas tecnolog��as de documentaci��n fotogram��trica y las bases de datos de los barredores l��ser terrestres, en los procesos de elaboraci��n, redacci��n y ejecuci��n de proyectos de restauraci��n y rehabilitaci��n arquitect��nicos. Los avances tecnol��gicos aparecidos en control m��trico, junto con las t��cnicas de imagen digital y los desarrollos fotogram��tricos, pueden aportar mejoras significativas en el proceso proyectual y permiten aplicar nuevos procedimientos de extracci��n de datos para generar de forma sencilla, bajo el control directo y supervisi��n de los responsables del proyecto, la informaci��n m��trica y documental m��s adecuada. Se establecen como principios, y por tanto como base para el dise��o de dicha herramienta, que los desarrollos aparecidos s�� han producido el uso extendido del sistema CAD (como instrumento de dibujo) as�� como el uso de la imagen digital como herramienta de documentaci��n. La herramienta a dise��ar se fundamenta por tanto en la imagen digital (im��genes digitales, im��genes rectificadas, ortofotograf��as, est��reo- modelos, estereo- ortofotograf��as) as�� como su integraci��n en autocad para un tratamiento interactivo. En la aplicaci��n de la fotogrametr��a a la disciplina arquitect��nica, se considera de inter��s estructurar aplicaciones con car��cter integrador que, con mayores capacidades de interactuaci��n y a partir de informaci��n veraz y rigurosa, permitan completar o elaborar documentos de inter��s proyectual, ABSTRACT This doctoral thesis explains the developments carried out, and finally patented with intellectual property rights, for the integration of the new photogrammetric technology documentation and terrestrial scanner databases in the preparation, documentation and implementation processes of restoration projects and architectural renovation. The technological advances in metric control, as well as the digital image techniques and photogrammetric developments, can together bring a significant improvement to the projecting process, and, under the direct control and supervision of those in charge of the project, can allow new data extraction processes to be applied in order to easily generate the most appropriate metric information and documentation. The principles and, therefore, the basis for the design of this tool are that the developments have indeed produced the widespread use of the CAD system (as a drawing instrument) and the use of digital images as a documentation tool. The tool to be designed is therefore based on digital images (rectify images, orthophotos, stereomodels, stereo-orthophotos) as well as its integration in Autocad for interactive processing. In the application of photogrammetry to the architectural discipline, what interests us is to structure applications of an integrative nature which, with a greater capacity for interaction and from accurate and thorough information, enable the completion or elaboration of documents that are of interest to the project.

Methodology for reconstructing early zebrafish development from in vivo multiphoton microscopy

Investigating cell dynamics during early zebrafish embryogenesis requires specific image acquisition and analysis strategies. Multiharmonic microscopy, i.e., second- and third-harmonic generations, allows imaging cell divisions and cell membranes in unstained zebrafish embryos from 1- to 1000-cell stage. This paper presents the design and implementation of a dedicated image processing pipeline (tracking and segmentation) for the reconstruction of cell dynamics during these developmental stages. This methodology allows the reconstruction of the cell lineage tree including division timings, spatial coordinates, and cell shape until the 1000-cell stage with minute temporal accuracy and micrometer spatial resolution. Data analysis of the digital embryos provides an extensive quantitative description of early zebrafish embryogenesis.

La videovigilancia : tecnolog��as actuales y aspectos sociopol��ticos

En este Proyecto de fin de carrera titulado: LA V��DEOVIGILANCIA: TECNOLOG��AS ACTUALES Y ASPECTOS SOCIOPOL��TICOS, tiene como objetivo hacer un estudio en los sistemas de V��deovigilancia basado en c��maras-IP, con fines de seguridad, control o supervisi��n. Nos basaremos en exponer los sistemas V��deovigilancia basados en c��mara-IP actuales de ultima generaci��n, cuya principal virtud de estos sistemas, es la comunicaci��n con otros lugares, o espacios p��blicos como privados y poder visualizar tanto en vivo como en diferido lo que este pasando en ese lugar y en ese momento o haya pasado a trav��s del protocolo de comunicaci��n-IP. Se explicara desde el m��s b��sico al m��s complejo sistema de videovigilancia-IP, tambi��n explicaremos su puesta en practica mediante los m��ltiples interconexiones que estos conlleven. Llegando a este punto, se nos plantea las siguientes cuestiones que da origen a este PFC. Estos sistemas de V��deovigilancia-IP, captan las im��genes por medio de las c��maras-IP, proporcionando su facilidad tanto de visionado/grabacion, como de control, ya que no es necesario estar presente e interactuando con otros sistemas digitales de diverso ��ndole actuales, gracias al protocolo-IP. Estos sistemas-IP, tienen su puesta en pr��ctica mediante las instalaciones requeridas ,estas podr��n ser sencillas o muy complejas de todos los sistemas-IP. Debido al gran aumento masivo, las tecnolog��as actuales de diverso ��ndole de c��maras-IP en materia de la v��deovigilancia en lugares p��blicos, y privados en nuestra sociedad actual, lo hace un medio particularmente invasivo y por ello resulta necesario tanto la concurrencia de condiciones que legitimen los tratamientos de datos de personas identificables, como la definici��n de los principios y garant��as que deban aplicarse ya que estas, repercutir��n sobre los derechos de las personas, lo que obligara a fijar ciertas garant��as. Se nos plantea los casos en los que la captaci��n y/o tratamiento de im��genes con fines de V��deovigilancia que pertenezcan a personas identificadas o identificables, ha obligado a Espa��a, y seg��n dispuesto por la Directiva 95/46/CE del Parlamento Europeo, a regularizar esta situaci��n mediante la Ley Org��nica de Protecci��n de Datos (LOPD) 15/1999 de 13 de diciembre, bajo los procedimientos del Estado espa��ol en materia sociopol��tica, y dando vigor a esta ley, mediante la aprobaci��n de la Instrucci��n 1/2006 de 8 de noviembre de 2006, cuyo m��ximo organismo es la Agencia espa��ola de Protecci��n de Datos (AGPD). Una vez planteada la motivaci��n y justificaci��n del proyecto, se derivan unos objetivos a cumplir con la realizaci��n del mismo. Los objetivos del proyecto se pueden diferenciar en dos clases principalmente. Los objetivos principales y objetivos secundarios. Los objetivos principales de este PFC, nacen directamente de las necesidades planteadas originalmente en materia de V��deovigilancia, tanto tecnol��gicamente basado en las c��maras-IP en la captaci��n y/o tratamiento de im��genes, as�� como sociopol��ticamente donde trataremos de describirlo mediante las indicaciones y criterios con casos pr��cticos y de c��mo deben de aplicarse seg��n la instrucci��n 1/2006 mediante la LOPD en materia de V��deovigilancia, en cuanto a la protecci��n de datos que puedan repercutir sobre el derecho de las personas. Por otra parte los objetivos secundarios, son la extensi��n del objetivo primario y son de orden cuantificador en este PFC, dando una explicaci��n m��s exhaustiva del objetivo principal. ABSTRACT In this final year project, entitled: THE VIDEOSURVEILLANCE: CURRENT TECHNOLOGIES AND POLITICALSOCIALS ASPECTS, aims to make a study of video surveillance systems based on IP cameras, for security, control or supervision. We will rely on to expose the camera based video surveillance systems IP-current last generation, whose main virtue of these systems, is communication with other places, or public and private spaces and to view both live and time so this happening in that place and at that time or passed through-IP communication protocol. He explained from the most basic to the most complex-IP video surveillance system, also explain its implementation into practice through multiple interconnections that these entail. Arriving at this point, we face the following issues which gave rise to this PFC. These IP-video surveillance systems, captured images through IP-cameras, providing both ease of viewing / recording, as a control, since it is not necessary to be present and interacting with other digital systems such diverse today, thanks IP-protocol. These systems-IP, have their implementation through the facilities required, these can be simple or very complex all-IP video surveillance systems. Due to the large increase in mass, current technologies of different kinds of IP cameras for video surveillance in public places, and private in our society, it makes a particularly invasive and therefore attendance is necessary both conditions that legitimize data processing of identifiable people, as the definition of the principles and safeguards to be applied as these will impact on the rights of the people, which forced to set certain guarantees. We face those cases in which the uptake and / or image processing video surveillance purposes belonging to identified or identifiable, has forced Spain, and as required by Directive 95/46/EC of the European Parliament, to regularize this situation by the Organic Law on Data Protection (LOPD) 15/1999 of December 13, under the procedures of the Spanish State in sociopolitical, and giving effect to this Act, with the approval of the Instruction 1/2006 of 8 November 2006, the governing body is the Spanish Agency for Data Protection (AGPD). Once raised the motivation and justification for the project, resulting in meeting targets to achieve the same. Project objectives can be differentiated into two main classes, the main objectives and secondary objectives: The main objectives of this PFC, born directly from requirements originally raised for capturing both technologically imaging me and try to describe where sociopolitically, the details and criteria as case studies and should be applied according to the instruction 1 / 2006 by the LOPD on video surveillance system in terms of data protection that could impact on the right people. Moreover the secondary objectives are the extension of the primary and are of a quantifier in this PFC, giving a fuller explanation of the main objective.

Design and Validation of an Optimized MB-OFDM Ultra Wideband Transceiver System

Esta tesis est�� incluida dentro del campo del campo de Multiband Orthogonal Frequency Division Multiplexing Ultra Wideband (MB-OFDM UWB), el cual ha adquirido una gran importancia en las comunicaciones inal��mbricas de alta tasa de datos en la ��ltima d��cada. UWB surgi�� con el objetivo de satisfacer la creciente demanda de conexiones inal��mbricas en interiores y de uso dom��stico, con bajo coste y alta velocidad. La disponibilidad de un ancho de banda grande, el potencial para alta velocidad de transmisi��n, baja complejidad y bajo consumo de energ��a, unido al bajo coste de implementaci��n, representa una oportunidad ��nica para que UWB se convierta en una soluci��n ampliamente utilizada en aplicaciones de Wireless Personal Area Network (WPAN). UWB est�� definido como cualquier transmisi��n que ocupa un ancho de banda de m��s de 20% de su frecuencia central, o m��s de 500 MHz. En 2002, la Comisi��n Federal de Comunicaciones (FCC) defini�� que el rango de frecuencias de transmisi��n de UWB legal es de 3.1 a 10.6 GHz, con una energ��a de transmisi��n de -41.3 dBm/Hz. Bajo las directrices de FCC, el uso de la tecnolog��a UWB puede aportar una enorme capacidad en las comunicaciones de corto alcance. Considerando las ecuaciones de capacidad de Shannon, incrementar la capacidad del canal requiere un incremento lineal en el ancho de banda, mientras que un aumento similar de la capacidad de canal requiere un aumento exponencial en la energ��a de transmisi��n. En los ��ltimos a��os, s diferentes desarrollos del UWB han sido extensamente estudiados en diferentes ��reas, entre los cuales, el protocolo de comunicaciones inal��mbricas MB-OFDM UWB est�� considerado como la mejor elecci��n y ha sido adoptado como est��ndar ISO/IEC para los WPANs. Combinando la modulaci��n OFDM y la transmisi��n de datos utilizando las t��cnicas de salto de frecuencia, el sistema MB-OFDM UWB es capaz de soportar tasas de datos con que pueden variar de los 55 a los 480 Mbps, alcanzando una distancia m��xima de hasta 10 metros. Se esperara que la tecnolog��a MB-OFDM tenga un consumo energ��tico muy bajo copando un are muy reducida en silicio, proporcionando soluciones de bajo coste que satisfagan las demandas del mercado. Para cumplir con todas estas expectativas, el desarrollo y la investigaci��n del MBOFDM UWB deben enfrentarse a varios retos, como son la sincronizaci��n de alta sensibilidad, las restricciones de baja complejidad, las estrictas limitaciones energ��ticas, la escalabilidad y la flexibilidad. Tales retos requieren un procesamiento digital de la se��al de ��ltima generaci��n, capaz de desarrollar sistemas que puedan aprovechar por completo las ventajas del espectro UWB y proporcionar futuras aplicaciones inal��mbricas en interiores. Esta tesis se centra en la completa optimizaci��n de un sistema de transceptor de banda base MB-OFDM UWB digital, cuyo objetivo es investigar y dise��ar un subsistema de comunicaci��n inal��mbrica para la aplicaci��n de las Redes de Sensores Inal��mbricas Visuales. La complejidad inherente de los procesadores FFT/IFFT y el sistema de sincronizaci��n as�� como la alta frecuencia de operaci��n para todos los elementos de procesamiento, se convierten en el cuello de la botella para el dise��o y la implementaci��n del sistema de UWB digital en base de banda basado en MB-OFDM de baja energ��a. El objetivo del transceptor propuesto es conseguir baja energ��a y baja complejidad bajo la premisa de un alto rendimiento. Las optimizaciones est��n realizadas tanto a nivel algor��tmico como a nivel arquitectural para todos los elementos del sistema. Una arquitectura hardware eficiente en consumo se propone en primer lugar para aquellos m��dulos correspondientes a n��cleos de computaci��n. Para el procesado de la Transformada R��pida de Fourier (FFT/IFFT), se propone un algoritmo mixed-radix, basado en una arquitectura con pipeline y se ha desarrollado un m��dulo de Decodificador de Viterbi (VD) equilibrado en coste-velocidad con el objetivo de reducir el consumo energ��tico e incrementar la velocidad de procesamiento. Tambi��n se ha implementado un correlador signo-bit simple basado en la sincronizaci��n del tiempo de s��mbolo es presentado. Este correlador es usado para detectar y sincronizar los paquetes de OFDM de forma robusta y precisa. Para el desarrollo de los subsitemas de procesamiento y realizar la integraci��n del sistema completo se han empleado tecnolog��as de ��ltima generaci��n. El dispositivo utilizado para el sistema propuesto es una FPGA Virtex 5 XC5VLX110T del fabricante Xilinx. La validaci��n el propuesta para el sistema transceptor se ha implementado en dicha placa de FPGA. En este trabajo se presenta un algoritmo, y una arquitectura, dise��ado con filosof��a de co-dise��o hardware/software para el desarrollo de sistemas de FPGA complejos. El objetivo principal de la estrategia propuesta es de encontrar una metodolog��a eficiente para el dise��o de un sistema de FPGA configurable optimizado con el empleo del m��nimo esfuerzo posible en el sistema de procedimiento de verificaci��n, por tanto acelerar el periodo de desarrollo del sistema. La metodolog��a de co-dise��o presentada tiene la ventaja de ser f��cil de usar, contiene todos los pasos desde la propuesta del algoritmo hasta la verificaci��n del hardware, y puede ser ampliamente extendida para casi todos los tipos de desarrollos de FPGAs. En este trabajo se ha desarrollado s��lo el sistema de transceptor digital de banda base por lo que la comprobaci��n de se��ales transmitidas a trav��s del canal inal��mbrico en los entornos reales de comunicaci��n sigue requiriendo componentes RF y un front-end anal��gico. No obstante, utilizando la metodolog��a de co-simulaci��n hardware/software citada anteriormente, es posible comunicar el sistema de transmisor y el receptor digital utilizando los modelos de canales propuestos por IEEE 802.15.3a, implementados en MATLAB. Por tanto, simplemente ajustando las caracter��sticas de cada modelo de canal, por ejemplo, un incremento del retraso y de la frecuencia central, podemos estimar el comportamiento del sistema propuesto en diferentes escenarios y entornos. Las mayores contribuciones de esta tesis son: ��� Se ha propuesto un nuevo algoritmo 128-puntos base mixto FFT usando la arquitectura pipeline multi-ruta. Los complejos multiplicadores para cada etapa de procesamiento son dise��ados usando la arquitectura modificada shiftadd. Los sistemas word length y twiddle word length son comparados y seleccionados bas��ndose en la se��al para cuantizaci��n del SQNR y el an��lisis de energ��as. ��� El desempe��o del procesador IFFT es analizado bajo diferentes situaciones aritm��ticas de bloques de punto flotante (BFP) para el control de desbordamiento, por tanto, para encontrar la arquitectura perfecta del algoritmo IFFT basado en el procesador FFT propuesto. ��� Para el sistema de receptor MB-OFDM UWB se ha empleado una sincronizaci��n del tiempo innovadora, de baja complejidad y esquema de compensaci��n, que consiste en funciones de Detector de Paquetes (PD) y Estimaci��n del Offset del tiempo. Simplificando el cross-correlation y maximizar las funciones probables solo a sign-bit, la complejidad computacional se ve reducida significativamente. ��� Se ha propuesto un sistema de decodificadores Viterbi de 64 estados de decisi��n-d��bil usando velocidad base-4 de arquitectura suma-comparaselecciona. El algoritmo Two-pointer Even tambi��n es introducido en la unidad de rastreador de origen con el objetivo de conseguir la eficiencia en el hardware. ��� Se han integrado varias tecnolog��as de ��ltima generaci��n en el completo sistema transceptor basebanda , con el objetivo de implementar un sistema de comunicaci��n UWB altamente optimizado. ��� Un dise��o de flujo mejorado es propuesto para el complejo sistema de implementaci��n, el cual puede ser usado para dise��os de Cadena de puertas de campo programable general (FPGA). El dise��o mencionado no s��lo reduce dram��ticamente el tiempo para la verificaci��n funcional, sino tambi��n provee un an��lisis autom��tico como los errores del retraso del output para el sistema de hardware implementado. ��� Un ambiente de comunicaci��n virtual es establecido para la validaci��n del propuesto sistema de transceptores MB-OFDM. Este m��todo es provisto para facilitar el uso y la conveniencia de analizar el sistema digital de basebanda sin parte frontera anal��gica bajo diferentes ambientes de comunicaci��n. Esta tesis doctoral est�� organizada en seis cap��tulos. En el primer cap��tulo se encuentra una breve introducci��n al campo del UWB, tanto relacionado con el proyecto como la motivaci��n del desarrollo del sistema de MB-OFDM. En el cap��tulo 2, se presenta la informaci��n general y los requisitos del protocolo de comunicaci��n inal��mbrica MBOFDM UWB. En el cap��tulo 3 se habla de la arquitectura del sistema de transceptor digital MB-OFDM de banda base . El dise��o del algoritmo propuesto y la arquitectura para cada elemento del procesamiento est�� detallado en este cap��tulo. Los retos de dise��o del sistema que involucra un compromiso de discusi��n entre la complejidad de dise��o, el consumo de energ��a, el coste de hardware, el desempe��o del sistema, y otros aspectos. En el cap��tulo 4, se ha descrito la co-dise��ada metodolog��a de hardware/software. Cada parte del flujo del dise��o ser�� detallado con algunos ejemplos que se ha hecho durante el desarrollo del sistema. Aprovechando esta estrategia de dise��o, el procedimiento de comunicaci��n virtual es llevado a cabo para probar y analizar la arquitectura del transceptor propuesto. Los resultados experimentales de la co-simulaci��n y el informe sint��tico de la implementaci��n del sistema FPGA son reflejados en el cap��tulo 5. Finalmente, en el cap��tulo 6 se incluye las conclusiones y los futuros proyectos, y tambi��n los resultados derivados de este proyecto de doctorado. ABSTRACT In recent years, the Wireless Visual Sensor Network (WVSN) has drawn great interest in wireless communication research area. They enable a wealth of new applications such as building security control, image sensing, and target localization. However, nowadays wireless communication protocols (ZigBee, Wi-Fi, and Bluetooth for example) cannot fully satisfy the demands of high data rate, low power consumption, short range, and high robustness requirements. New communication protocol is highly desired for such kind of applications. The Ultra Wideband (UWB) wireless communication protocol, which has increased in importance for high data rate wireless communication field, are emerging as an important topic for WVSN research. UWB has emerged as a technology that offers great promise to satisfy the growing demand for low-cost, high-speed digital wireless indoor and home networks. The large bandwidth available, the potential for high data rate transmission, and the potential for low complexity and low power consumption, along with low implementation cost, all present a unique opportunity for UWB to become a widely adopted radio solution for future Wireless Personal Area Network (WPAN) applications. UWB is defined as any transmission that occupies a bandwidth of more than 20% of its center frequency, or more than 500 MHz. In 2002, the Federal Communications Commission (FCC) has mandated that UWB radio transmission can legally operate in the range from 3.1 to 10.6 GHz at a transmitter power of ���41.3 dBm/Hz. Under the FCC guidelines, the use of UWB technology can provide enormous capacity over short communication ranges. Considering Shannon���s capacity equations, increasing the channel capacity requires linear increasing in bandwidth, whereas similar channel capacity increases would require exponential increases in transmission power. In recent years, several different UWB developments has been widely studied in different area, among which, the MB-OFDM UWB wireless communication protocol is considered to be the leading choice and has recently been adopted in the ISO/IEC standard for WPANs. By combing the OFDM modulation and data transmission using frequency hopping techniques, the MB-OFDM UWB system is able to support various data rates, ranging from 55 to 480 Mbps, over distances up to 10 meters. The MB-OFDM technology is expected to consume very little power and silicon area, as well as provide low-cost solutions that can satisfy consumer market demands. To fulfill these expectations, MB-OFDM UWB research and development have to cope with several challenges, which consist of high-sensitivity synchronization, low- complexity constraints, strict power limitations, scalability, and flexibility. Such challenges require state-of-the-art digital signal processing expertise to develop systems that could fully take advantages of the UWB spectrum and support future indoor wireless applications. This thesis focuses on fully optimization for the MB-OFDM UWB digital baseband transceiver system, aiming at researching and designing a wireless communication subsystem for the Wireless Visual Sensor Networks (WVSNs) application. The inherent high complexity of the FFT/IFFT processor and synchronization system, and high operation frequency for all processing elements, becomes the bottleneck for low power MB-OFDM based UWB digital baseband system hardware design and implementation. The proposed transceiver system targets low power and low complexity under the premise of high performance. Optimizations are made at both algorithm and architecture level for each element of the transceiver system. The low-power hardwareefficient structures are firstly proposed for those core computation modules, i.e., the mixed-radix algorithm based pipelined architecture is proposed for the Fast Fourier Transform (FFT/IFFT) processor, and the cost-speed balanced Viterbi Decoder (VD) module is developed, in the aim of lowering the power consumption and increasing the processing speed. In addition, a low complexity sign-bit correlation based symbol timing synchronization scheme is presented so as to detect and synchronize the OFDM packets robustly and accurately. Moreover, several state-of-the-art technologies are used for developing other processing subsystems and an entire MB-OFDM digital baseband transceiver system is integrated. The target device for the proposed transceiver system is Xilinx Virtex 5 XC5VLX110T FPGA board. In order to validate the proposed transceiver system in the FPGA board, a unified algorithm-architecture-circuit hardware/software co-design environment for complex FPGA system development is presented in this work. The main objective of the proposed strategy is to find an efficient methodology for designing a configurable optimized FPGA system by using as few efforts as possible in system verification procedure, so as to speed up the system development period. The presented co-design methodology has the advantages of easy to use, covering all steps from algorithm proposal to hardware verification, and widely spread for almost all kinds of FPGA developments. Because only the digital baseband transceiver system is developed in this thesis, the validation of transmitting signals through wireless channel in real communication environments still requires the analog front-end and RF components. However, by using the aforementioned hardware/software co-simulation methodology, the transmitter and receiver digital baseband systems get the opportunity to communicate with each other through the channel models, which are proposed from the IEEE 802.15.3a research group, established in MATLAB. Thus, by simply adjust the characteristics of each channel model, e.g. mean excess delay and center frequency, we can estimate the transmission performance of the proposed transceiver system through different communication situations. The main contributions of this thesis are: ��� A novel mixed radix 128-point FFT algorithm by using multipath pipelined architecture is proposed. The complex multipliers for each processing stage are designed by using modified shift-add architectures. The system wordlength and twiddle word-length are compared and selected based on Signal to Quantization Noise Ratio (SQNR) and power analysis. ��� IFFT processor performance is analyzed under different Block Floating Point (BFP) arithmetic situations for overflow control, so as to find out the perfect architecture of IFFT algorithm based on the proposed FFT processor. ��� An innovative low complex timing synchronization and compensation scheme, which consists of Packet Detector (PD) and Timing Offset Estimation (TOE) functions, for MB-OFDM UWB receiver system is employed. By simplifying the cross-correlation and maximum likelihood functions to signbit only, the computational complexity is significantly reduced. ��� A 64 state soft-decision Viterbi Decoder system by using high speed radix-4 Add-Compare-Select architecture is proposed. Two-pointer Even algorithm is also introduced into the Trace Back unit in the aim of hardware-efficiency. ��� Several state-of-the-art technologies are integrated into the complete baseband transceiver system, in the aim of implementing a highly-optimized UWB communication system. ��� An improved design flow is proposed for complex system implementation which can be used for general Field-Programmable Gate Array (FPGA) designs. The design method not only dramatically reduces the time for functional verification, but also provides automatic analysis such as errors and output delays for the implemented hardware systems. ��� A virtual communication environment is established for validating the proposed MB-OFDM transceiver system. This methodology is proved to be easy for usage and convenient for analyzing the digital baseband system without analog frontend under different communication environments. This PhD thesis is organized in six chapters. In the chapter 1 a brief introduction to the UWB field, as well as the related work, is done, along with the motivation of MBOFDM system development. In the chapter 2, the general information and requirement of MB-OFDM UWB wireless communication protocol is presented. In the chapter 3, the architecture of the MB-OFDM digital baseband transceiver system is presented. The design of the proposed algorithm and architecture for each processing element is detailed in this chapter. Design challenges of such system involve trade-off discussions among design complexity, power consumption, hardware cost, system performance, and some other aspects. All these factors are analyzed and discussed. In the chapter 4, the hardware/software co-design methodology is proposed. Each step of this design flow will be detailed by taking some examples that we met during system development. Then, taking advantages of this design strategy, the Virtual Communication procedure is carried out so as to test and analyze the proposed transceiver architecture. Experimental results from the co-simulation and synthesis report of the implemented FPGA system are given in the chapter 5. The chapter 6 includes conclusions and future work, as well as the results derived from this PhD work.

Caracterizaci��n automatizada de texturas de menas mediante an��lisis digital de imagen para su aplicaci��n geometal��rgica

La mineralog��a de procesos se ha convertido en los ��ltimos a��os en una herramienta indispensable dentro del ��mbito minero-metal��rgico debido fundamentalmente a la emergencia de la Geometalurgia. Esta disciplina en auge, a trav��s de la integraci��n de datos geol��gicos, mineros y metal��rgicos, proporciona la informaci��n necesaria para que el circuito de concentraci��n mineral pueda responder de manera r��pida y eficaz a la variabilidad mineral��gica inherente a la geolog��a del yacimiento. Para la generaci��n del modelo geometal��rgico, la mineralog��a de procesos debe aportar datos cuantitativos sobre los rasgos mineral��gicos influyentes en el comportamiento de los minerales y para ello se apoya en el uso de sistemas de an��lisis mineral��gico automatizado. Estos sistemas son capaces de proporcionar gran cantidad de datos mineral��gicos de manera r��pida y precisa. Sin embargo, cuando se trata de la caracterizaci��n de la textura, el mineralogista debe recurrir a descripciones cualitativas basadas en la observaci��n, ya que los sistemas actuales no ofrecen informaci��n textural automatizada. Esta tesis doctoral surge precisamente para proporcionar de manera sistem��tica informaci��n textural relevante para los procesos de concentraci��n mineral. La tesis tiene como objetivo principal la identificaci��n y caracterizaci��n del tipo de intercrecimiento que un determinado mineral presenta en las part��culas minerales, e inicialmente se han tenido en cuenta los siete tipos de intercrecimiento considerados como los m��s relevantes bajo el punto de vista del comportamiento de las part��culas minerales durante flotaci��n, lixiviaci��n y molienda. Para alcanzar este objetivo se ha desarrollado una metodolog��a basada en el dise��o y c��lculo de una serie de ��ndices num��ricos, a los que se ha llamado ��ndices mineral��rgicos, que cumplen una doble funci��n: por un lado, cada ��ndice aporta informaci��n relevante para caracterizar los principales rasgos mineral��gicos que gobiernan el comportamiento de las part��culas minerales a lo largo de los procesos de concentraci��n y por otro lado, estos ��ndices sirven como variables discriminantes para identificar el tipo de intercrecimiento mineral mediante la aplicaci��n de An��lisis Discriminante. Dentro del conjunto de ��ndices propuestos en este trabajo, se han considerado algunos ��ndices propuestos por otros autores para su aplicaci��n tanto en el ��mbito de la mineralog��a como en otros ��mbitos de la ciencia de materiales. Se trata del ��ndice de Contig��idad (Gurland, 1958), ��ndice de Intercrecimiento (Amstutz y Giger, 1972) e ��ndice de Coordinaci��n (Jeulin, 1981), adaptados en este caso para el an��lisis de part��culas minerales. El dise��o de los ��ndices se ha basado en los principios b��sicos de la Estereolog��a y el an��lisis digital de imagen, y su c��lculo se ha llevado a cabo aplicando el m��todo de interceptos lineales mediante la programaci��n en MATLAB de varias rutinas. Este m��todo estereol��gico permite recoger una serie de medidas a partir de las que es posible calcular varios par��metros, tanto estereol��gicos como geom��tricos, que han servido de base para calcular los ��ndices mineral��rgicos. Para evaluar la capacidad discriminatoria de los ��ndices mineral��rgicos se han seleccionado 200 casos en los que se puede reconocer de manera clara alguno de los siete tipos de intercrecimiento considerados inicialmente en este trabajo. Para cada uno de estos casos se han calculado los ��ndices mineral��rgicos y se ha aplicado An��lisis Discriminante, obteniendo un porcentaje de acierto en la clasificaci��n del 95%. Esta cifra indica que los ��ndices propuestos son discriminadores fiables del tipo de intercrecimiento. Una vez probada la capacidad discriminatoria de los ��ndices, la metodolog��a desarrollada ha sido aplicada para caracterizar una muestra de un concentrado de cobre procedente de la mina Kansanshi (Zambia). Esta caracterizaci��n se ha llevado a cabo para obtener la distribuci��n de calcopirita seg��n su tipo de intercrecimiento. La utilidad de esta distribuci��n ha sido analizada bajo diferentes puntos de vista y en todos ellos los ��ndices mineral��rgicos aportan informaci��n valiosa para caracterizar el comportamiento mineral��rgico de las part��culas minerales. Los resultados derivados tanto del An��lisis Discriminante como de la caracterizaci��n del concentrado de Kansanshi muestran la fiabilidad, utilidad y versatilidad de la metodolog��a desarrollada, por lo que su integraci��n como herramienta rutinaria en los sistemas actuales de an��lisis mineral��gico pondr��a a disposici��n del mineralurgista gran cantidad de informaci��n textural complementaria a la informaci��n ofrecida por las t��cnicas actuales de caracterizaci��n mineral��gica. ABSTRACT Process mineralogy has become in the last decades an essential tool in the mining and metallurgical sphere, especially driven by the emergence of Geometallurgy. This emergent discipline provides required information to efficiently tailor the circuit performance to the mineralogical variability inherent to ore deposits. To contribute to the Geometallurgical model, process mineralogy must provide quantitative data about the main mineralogical features implied in the minerallurgical behaviour of minerals. To address this characterisation, process mineralogy relies on automated systems. These systems are capable of providing a large amount of data quickly and accurately. However, when it comes to the characterisation of texture, mineralogists need to turn to qualitative descriptions based on observation, due to the fact that current systems can not offer quantitative textural information in a routine way. Aiming at the automated characterisation of textural information, this doctoral thesis arises to provide textural information relevant for concentration processes in a systematic way. The main objective of the thesis is the automated identification and characterisation of intergrowth types in mineral particles. Initially, the seven intergrowth types most relevant for flotation, leaching and grinding are considered. To achieve this goal, a methodology has been developed based on the computation of a set of numerical indices, which have been called minerallurgical indices. These indices have been designed with two main purposes: on the one hand, each index provides information to characterise the main mineralogical features which determine particle behaviour during concentration processes and, on the other hand, these indices are used as discriminant variables for identifying the intergrowth type by Discriminant Analysis. Along with the indices developed in this work, three indices proposed by other authors belonging to different fields of materials science have been also considered after being adapted to the analysis of mineral particles. These indices are Contiguity Index (Gurland, 1958), Intergrowth Index (Amstutz and Giger, 1972) and Coordination Index (Jeulin, 1981). The design of minerallurgical indices is based on the fundamental principles of Stereology and Digital Image Analysis. Their computation has been carried out using the linear intercepts method, implemented by means of MATLAB programming. This stereological method provides a set of measurements to obtain several parameters, both stereological and geometric. Based on these parameters, minerallurgical indices have been computed. For the assessment of the discriminant capacity of the developed indices, 200 cases have been selected according to their internal structure, so that one of the seven intergrowth types initially considered in this work can be easily recognised in any of their constituents. Minerallurgical indices have been computed for each case and used as discriminant variables. After applying discriminant analysis, 95% of the cases were correctly classified. This result shows that the proposed indices are reliable identifiers of intergrowth type. Once the discriminant power of the indices has been assessed, the developed methodology has been applied to characterise a copper concentrate sample from the Kansanshi copper mine (Zambia). This characterisation has been carried out to quantify the distribution of chalcopyrite with respect to intergrowth types. Different examples of the application of this distribution have been given to test the usefulness of the method. In all of them, the proposed indices provide valuable information to characterise the minerallurgical behaviour of mineral particles. Results derived from both Discriminant Analysis and the characterisation of the Kansanshi concentrate show the reliability, usefulness and versatility of the developed methodology. Therefore, its integration as a routine tool in current systems of automated mineralogical analysis should make available for minerallurgists a great deal of complementary information to treat the ore more efficiently.

New perspectives on quantitative textural analysis

Process mineralogy provides the mineralogical information required by geometallurgists to address the inherent variation of geological data. The successful benefitiation of ores mostly depends on the ability of mineral processing to be efficiently adapted to the ore characteristics, being liberation one of the most relevant mineralogical parameters. The liberation characteristics of ores are intimately related to mineral texture. Therefore, the characterization of liberation necessarily requieres the identification and quantification of those textural features with a major bearing on mineral liberation. From this point of view grain size, bonding between mineral grains and intergrowth types are considered as the most influential textural attributes. While the quantification of grain size is a usual output of automated current technologies, information about grain boundaries and intergrowth types is usually descriptive and difficult to quantify to be included in the geometallurgical model. Aiming at the systematic and quantitative analysis of the intergrowth type within mineral particles, a new methodology based on digital image analysis has been developed. In this work, the ability of this methodology to achieve a more complete characterization of liberation is explored by the analysis of chalcopyrite in the rougher concentrate of the Kansanshi copper-gold mine (Zambia). Results obtained show that the method provides valuable textural information to achieve a better understanding of mineral behaviour during concentration processes. The potential of this method is enhanced by the fact that it provides data unavailable by current technologies. This opens up new perspectives on the quantitative analysis of mineral processing performance based on textural attributes.