918 resultados para Pattern recognition techniques
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State of the art methods for disparity estimation achieve good results for single stereo frames, but temporal coherence in stereo videos is often neglected. In this paper we present a method to compute temporally coherent disparity maps. We define an energy over whole stereo sequences and optimize their Conditional Random Field (CRF) distributions using mean-field approximation. We introduce novel terms for smoothness and consistency between the left and right views, and perform CRF optimization by fast, iterative spatio-temporal filtering with linear complexity in the total number of pixels. Our results rank among the state of the art while having significantly less flickering artifacts in stereo sequences.
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Scientific background: Marine mammals use sound for communication, navigation and prey detection. Acoustic sensors therefore allow the detection of marine mammals, even during polar winter months, when restricted visibility prohibits visual sightings. The animals are surrounded by a permanent natural soundscape, which, in polar waters, is mainly dominated by the movement of ice. In addition to the detection of marine mammals, acoustic long-term recordings provide information on intensity and temporal variability of characteristic natural and anthropogenic background sounds, as well as their influence on the vocalization of marine mammals Scientific objectives: The PerenniAL Acoustic Observatory in the Antarctic Ocean (PALAOA, Hawaiian "whale") near Neumayer Station is intended to record the underwater soundscape in the vicinity of the shelf ice edge over the duration of several years. These long-term recordings will allow studying the acoustic repertoire of whales and seals continuously in an environment almost undisturbed by humans. The data will be analyzed to (1) register species specific vocalizations, (2) infer the approximate number of animals inside the measuring range, (3) calculate their movements relative to the observatory, and (4) examine possible effects of the sporadic shipping traffic on the acoustic and locomotive behaviour of marine mammals. The data, which are largely free of anthropogenic noise, provide also a base to set up passive acoustic mitigation systems used on research vessels. Noise-free bioacoustic data thereby represent the foundation for the development of automatic pattern recognition procedures in the presence of interfering sounds, e.g. propeller noise.
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This paper presents an automatic modulation classifier for electronic warfare applications. It is a pattern recognition modulation classifier based on statistical features of the phase and instantaneous frequency. This classifier runs in a real time operation mode with sampling rates in excess of 1 Gsample/s. The hardware platform for this application is a Field Programmable Gate Array (FPGA). This AMC is subsidiary of a digital channelised receiver also implemented in the same platform.
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This paper describes a method for identifying topics in text published in social media, by applying topic recognition techniques that exploit DBpedia. We evaluate such method for social media in Spanish and we provide the results of the evaluation performed.
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We propose a level set based variational approach that incorporates shape priors into edge-based and region-based models. The evolution of the active contour depends on local and global information. It has been implemented using an efficient narrow band technique. For each boundary pixel we calculate its dynamic according to its gray level, the neighborhood and geometric properties established by training shapes. We also propose a criterion for shape aligning based on affine transformation using an image normalization procedure. Finally, we illustrate the benefits of the our approach on the liver segmentation from CT images.
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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.
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This work presents a method to detect Microcalcifications in Regions of Interest from digitized mammograms. The method is based mainly on the combination of Image Processing, Pattern Recognition and Artificial Intelligence. The Top-Hat transform is a technique based on mathematical morphology operations that, in this work is used to perform contrast enhancement of microcalcifications in the region of interest. In order to find more or less homogeneous regions in the image, we apply a novel image sub-segmentation technique based on Possibilistic Fuzzy c-Means clustering algorithm. From the original region of interest we extract two window-based features, Mean and Deviation Standard, which will be used in a classifier based on a Artificial Neural Network in order to identify microcalcifications. Our results show that the proposed method is a good alternative in the stage of microcalcifications detection, because this stage is an important part of the early Breast Cancer detection
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Los objetivos de este proyecto son proporcionar la teoría, los ejercicios y otros recursos necesarios para que los alumnos de la EUIT de Telecomunicación con un nivel A1 en el Marco Común Europeo de Referencia para las Lenguas (MCERL) puedan obtener el nivel A2 en inglés sin necesidad de asistir a clases ni matricularse en cursos presenciales. La plataforma utilizada para conseguir este fin es Moodle, siendo utilizada en la página web de ILLLab. Este curso online sirve para alcanzar los conocimientos requeridos en la asignatura optativa Introduction to English for Professional and Academic Communication I que parte del nivel B1. Se realiza una propuesta de la gramática con sus correspondientes ejemplos y ejercicios basados todos ellos en adaptaciones de actividades publicadas en un corpus de libros de texto. Se añaden recursos (pequeñas lecturas, videos, enlaces) que se consideran apropiados para el tema tratado. Por otro lado, también se persigue solucionar el problema de los cursos de idiomas basados en e-learning ya que no proporcionan las herramientas necesarias para poner en práctica la expresión oral. Para ello, se aporta una aplicación basada en técnicas de reconocimiento de voz, con tres actividades en las que los resultados han de darse de forma hablada y con la correcta pronunciación. Así, se busca dar una base de conocimientos y experiencias prácticas para futuros proyectos basados en herramientas de síntesis y reconocimiento de voz, además de buscar un nuevo enfoque en el estudio de idiomas. Abstract: The objectives of this project are to provide the theory, exercises and other resources for students at the EUIT Telecommunications with A1 level in the Common European Framework of Reference for Languages (MCERL) in order to get A2 level in English without attending face-to-face courses. The platform used to achieve this aim is Moodle, which is currently being used in ILLLab website. This online course is due to attain the knowledge required in the optional subject Introduction to English for Professional and Academic Communication I which is based on the B1 level. It is a proposal of grammar with corresponding examples and exercises all based on adaptations of activities posted on a corpus of textbooks. It also adds resources (short readings, videos or links) that are appropriate for the subject. On the other hand, this project aims to solve the problem of language courses based on e-learning because these do not usually provide the student with the necessary tools to practice speaking. For this, we develop an application based on speech recognition techniques and propose three activities to practice speaking, and pronunciation. The proposal seeks to provide knowledge and practical experience for future projects based on synthesis tools and voice recognition, and means a new approach to e-learning courses for the study of languages.
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Inicio del desarrollo de un algoritmo eficiente orientado a dispositivos con baja capacidad de proceso, que ayude a personas sin necesariamente una preparación adecuada a llevar a cabo un proceso de toma de una señal biológica, como puede ser un electrocardiograma. La aplicación deberá, por tanto, asesorar en la toma de la señal al usuario, evaluar la calidad de la grabación obtenida, y en tiempo seudo real, comprobar si la calidad de la señal obtenida es suficientemente buena para su posterior diagnóstico, de tal modo que en caso de que sea necesaria una repetición de la prueba médica, esta pueda realizarse de inmediato. Además, el algoritmo debe extraer las características más relevantes de la señal electrocardiográfica, procesarlas, y obtener una serie de patrones significativos que permitan la orientación a la diagnosis de algunas de las patologías más comunes que se puedan extraer de la información de las señales cardíacas. Para la extracción, evaluación y toma de decisiones de este proceso previo a la generación del diagnóstico, se seguirá la arquitectura clásica de un sistema de detección de patrones, definiendo las clases que sean necesarias según el número de patologías que se deseen identificar. Esta información de diagnosis, obtenida mediante la identificación del sistema de reconocimiento de patrones, podría ser de ayuda u orientación para la posterior revisión de la prueba por parte de un profesional médico cualificado y de manera remota, evitando así el desplazamiento del mismo a zonas donde, por los medios existentes a día de hoy, es muy remota la posibilidad de presencia de personal sanitario. ABTRACT Start of development of an efficient algorithm designed to devices with low processing power, which could help people without adequate preparation to undertake a process of taking a biological signal, such as an electrocardiogram. Therefore, the application must assist the user in taking the signal and evaluating the quality of the recording. All of this must to be in live time. It must to check the quality of the signal obtained, and if is it necessary a repetition of the test, this could be done immediately. Furthermore, the algorithm must extract the most relevant features of the ECG signal, process it, and get meaningful patterns that allow to a diagnosis orientation of some of the more common diseases that can be drawn from the cardiac signal information. For the extraction, evaluation and decision making in this previous process to the generation of diagnosis, we will follow the classic architecture of a pattern recognition system, defining the necessary classes according to the number of pathologies that we wish to identify. This diagnostic information obtained by identifying the pattern recognition system could be for help or guidance for further review of the signal by a qualified medical professional, and it could be done remotely, thus avoiding the movements to areas where nowadays it is extremely unlikely to place any health staff, due to the poor economic condition.
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Moment invariants have been thoroughly studied and repeatedly proposed as one of the most powerful tools for 2D shape identification. In this paper a set of such descriptors is proposed, being the basis functions discontinuous in a finite number of points. The goal of using discontinuous functions is to avoid the Gibbs phenomenon, and therefore to yield a better approximation capability for discontinuous signals, as images. Moreover, the proposed set of moments allows the definition of rotation invariants, being this the other main design concern. Translation and scale invariance are achieved by means of standard image normalization. Tests are conducted to evaluate the behavior of these descriptors in noisy environments, where images are corrupted with Gaussian noise up to different SNR values. Results are compared to those obtained using Zernike moments, showing that the proposed descriptor has the same performance in image retrieval tasks in noisy environments, but demanding much less computational power for every stage in the query chain.
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Due to the intensive use of mobile phones for diferent purposes, these devices usually contain condential information which must not be accessed by another person apart from the owner of the device. Furthermore, the new generation phones commonly incorporate an accelerometer which may be used to capture the acceleration signals produced as a result of owner s gait. Nowadays, gait identication in basis of acceleration signals is being considered as a new biometric technique which allows blocking the device when another person is carrying it. Although distance based approaches as Euclidean distance or dynamic time warping have been applied to solve this identication problem, they show di±culties when dealing with gaits at diferent speeds. For this reason, in this paper, a method to extract an average template from instances of the gait at diferent velocities is presented. This method has been tested with the gait signals of 34 subjects while walking at diferent motion speeds (slow, normal and fast) and it has shown to improve the performance of Euclidean distance and classical dynamic time warping.
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En los últimos años, ha crecido de forma significativa el interés por la utilización de dispositivos capaces de reconocer gestos humanos. En este trabajo, se pretenden reconocer gestos manuales colocando sensores en la mano de una persona. El reconocimiento de gestos manuales puede ser implementado para diversos usos y bajo diversas plataformas: juegos (Wii), control de brazos robóticos, etc. Como primer paso, se realizará un estudio de las actuales técnicas de reconocimiento de gestos que utilizan acelerómetros como sensor de medida. En un segundo paso, se estudiará como los acelerómetros pueden utilizarse para intentar reconocer los gestos que puedan realizar una persona (mover el brazo hacia un lado, girar la mano, dibujar un cuadrado, etc.) y los problemas que de su utilización puedan derivarse. Se ha utilizado una IMU (Inertial Measurement Unit) como sensor de medida. Está compuesta por tres acelerómetros y tres giróscopos (MTi-300 de Xsens). Con las medidas que proporcionan estos sensores se realiza el cálculo de la posición y orientación de la mano, representando esta última en función de los ángulos de Euler. Un aspecto importante a destacar será el efecto de la gravedad en las medidas de las aceleraciones. A través de diversos cálculos y mediante la ayuda de los giróscopos se podrá corregir dicho efecto. Por último, se desarrollará un sistema que identifique la posición y orientación de la mano como gestos reconocidos utilizando lógica difusa. Tanto para la adquisición de las muestras, como para los cálculos de posicionamiento, se ha desarrollado un código con el programa Matlab. También, con este mismo software, se ha implementado un sistema de lógica difusa con la que se realizará el reconocimiento de los gestos, utilizando la herramienta FIS Editor. Las pruebas realizadas han consistido en la ejecución de nueve gestos por diferentes personas teniendo una tasa de reconocimiento comprendida entre el 90 % y 100 % dependiendo del gesto a identificar. ABSTRACT In recent years, it has grown significantly interest in the use of devices capable of recognizing human gestures. In this work, we aim to recognize hand gestures placing sensors on the hand of a person. The recognition of hand gestures can be implemented for different applications on different platforms: games (Wii), control of robotic arms ... As a first step, a study of current gesture recognition techniques that use accelerometers and sensor measurement is performed. In a second step, we study how accelerometers can be used to try to recognize the gestures that can make a person (moving the arm to the side, rotate the hand, draw a square, etc...) And the problems of its use can be derived. We used an IMU (Inertial Measurement Unit) as a measuring sensor. It comprises three accelerometers and three gyroscopes (Xsens MTI-300). The measures provided by these sensors to calculate the position and orientation of the hand are made, with the latter depending on the Euler angles. An important aspect to note is the effect of gravity on the measurements of the accelerations. Through various calculations and with the help of the gyroscopes can correct this effect. Finally, a system that identifies the position and orientation of the hand as recognized gestures developed using fuzzy logic. Both the acquisition of samples to calculate position, a code was developed with Matlab program. Also, with the same software, has implemented a fuzzy logic system to be held with the recognition of gestures using the FIS Editor. Tests have involved the execution of nine gestures by different people having a recognition rate between 90% and 100% depending on the gesture to identify.
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El Hogar Digital Accesible (HDA) de la ETSIST nace con el propósito de acercar las nuevas Tecnologías de la Información a las personas que precisan de necesidades concretas de accesibilidad y usabilidad, dotándoles de herramientas que les permitan aumentar su calidad de vida, confort, seguridad y autonomía. El entorno del HDA consta de elementos de control para puertas, persianas, iluminación, agua o gas, sensores de temperatura, incendios, gas, sistemas de climatización, sistemas de entretenimiento y sistemas de seguridad tales como detectores de presencia y alarmas. Todo ello apoyado sobre una arquitectura de red que proporciona una pasarela residencial y un acceso a banda ancha. El objetivo principal de este PFG ha sido el desarrollo de un sistema de autenticación para el Hogar Digital Accesible de bajo coste. La idea de integrar un sistema de autenticación en el HDA, surge de la necesidad de proteger de accesos no deseados determinados servicios disponibles dentro de un ámbito privado. Algunos de estos servicios pueden ser tales como el acceso a la lectura de los mensajes disponibles en el contestador automático, el uso de equipos multimedia, la desconexión de alarmas de seguridad o simplemente la configuración de ambientes según el usuario que esté autenticado (intensidad de luz, temperatura de la sala, etc.). En el desarrollo han primado los principios de accesibilidad, usabilidad y seguridad necesarios para la creación de un entorno no invasivo, que permitiera acreditar la identidad del usuario frente al sistema HDA. Se ha planteado como posible solución, un sistema basado en el reconocimiento de un trazo realizado por el usuario. Este trazo se usará como clave de cara a validar a los usuarios. El usuario deberá repetir el trazado que registró en el sistema para autenticarse. Durante la ejecución del presente PFG, se justificará la elección de este mecanismo de autenticación frente a otras alternativas disponibles en el mercado. Para probar la aplicación, se ha podido contar con dos periféricos de distintas gamas, el uDraw creado para la PS3 que se compone de una tableta digitalizadora y un lápiz que permite recoger los trazos realizados por el usuario de forma inalámbrica y la tableta digitalizadora Bamboo de Wacom. La herramienta desarrollada permite a su vez, la posibilidad de ser usada por otro tipo de dispositivos como es el caso del reloj con acelerómetro de 3 ejes de Texas Instruments Chronos eZ430 capaz de trasladar los movimientos del usuario al puntero de un ratón. El PFG se encuentra dividido en tres grandes bloques de flujo de trabajo. El primero se centra en el análisis del sistema y las tecnologías que lo componen, incluyendo los distintos algoritmos disponibles para realizar la autenticación basada en reconocimiento de patrones aplicados a imágenes que mejor se adaptan a las necesidades del usuario. En el segundo bloque se recoge una versión de prueba basada en el análisis y el diseño UML realizado previamente, sobre la que se efectuaron pruebas de concepto y se comprobó la viabilidad del proyecto. El último bloque incluye la verificación y validación del sistema mediante pruebas que certifican que se han alcanzado los niveles de calidad necesarios para la consecución de los objetivos planteados, generando finalmente la documentación necesaria. Como resultado del trabajo realizado, se ha obtenido un sistema que plantea una arquitectura fácilmente ampliable lograda a través del uso de técnicas como la introspección, que permiten separar la lógica de la capa de negocio del código que la implementa, pudiendo de forma simple e intuitiva sustituir código mediante ficheros de configuración, lo que hace que el sistema sea flexible y escalable. Tras la realización del PFG, se puede concluir que el producto final obtenido ha respondido de forma satisfactoria alcanzando los niveles de calidad requeridos, siendo capaz de proporcionar un sistema de autenticación alternativo a los convencionales, manteniendo unas cotas de seguridad elevadas y haciendo de la accesibilidad y el precio sus características más reseñables. ABSTRACT. Accessible Digital Home (HDA) of the ETSIST was created with the aim of bringing the latest information and communications technologies closer to the people who has special needs of accessibility and usability increasing their quality of life, comfort, security and autonomy. The HDA environment has different control elements for doors, blinds, lighting, water or gas, temperature sensors, fire protection systems, gas flashover, air conditioning systems, entertainments systems and security systems such as intruders detectors and alarms. Everything supported by an architecture net which provides a broadband residential services gateway. The main goal of this PFG was the development of a low-cost authentication system for the Accessible Digital Home. The idea of integrating an authentication system on the HDA, stems from the need to safeguard certain private key network resources from unauthorized access. Some of said resources are the access to the answering machine messages, the use of multimedia devices, the alarms deactivation or the parameter settings for each environment as programmed by the authenticated user (light intensity, room temperature, etc.). During the development priority was given to concepts like accessibility, usability and security. All of them necessary to create a non invasive environment that allows the users to certify their identity. A system based on stroke pattern recognition, was considered as a possible solution. This stroke is used as a key to validate users. The user must repeat the stroke that was saved on the system to validate access. The selection of this authentication mechanism among the others available options will be justified during this PFG. Two peripherals with different ranges were used to test the application. One of them was uDraw design for the PS3. It is wireless and is formed by a pen and a drawing tablet that allow us to register the different strokes drawn by the user. The other one was the Wacom Bamboo tablet, that supports the same functionality but with better accuracy. The developed tool allows another kind of peripherals like the 3-axes accelerometer digital wristwatch Texas Instruments Chronos eZ430 capable of transfering user movements to the mouse cursor. The PFG is divided by three big blocks that represent different workflows. The first block is focused on the system analysis and the technologies related to it, including algorithms for image pattern recognition that fits the user's needs. The second block describes how the beta version was developed based on the UML analysis and design previously done. It was tested and the viability of the project was verified. The last block contains the system verification and validation. These processes certify that the requirements have been fulfilled as well as the quality levels needed to reach the planned goals. Finally all the documentation has been produced. As a result of the work, an expandable system has been created, due to the introspection that provides the opportunity to separate the business logic from the code that implements it. With this technique, the code could be replaced throughout configuration files which makes the system flexible and highly scalable. Once the PFG has finished, it must therefore be concluded that the final product has been a success and high levels of quality have been achieved. This authentication tool gives us a low-cost alternative to the conventional ones. The new authentication system remains security levels reasonably high giving particular emphasis to the accessibility and the price.
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El presente proyecto trata sobre uno de los campos más problemáticos de la inteligencia artificial, el reconocimiento facial. Algo tan sencillo para las personas como es reconocer una cara conocida se traduce en complejos algoritmos y miles de datos procesados en cuestión de segundos. El proyecto comienza con un estudio del estado del arte de las diversas técnicas de reconocimiento facial, desde las más utilizadas y probadas como el PCA y el LDA, hasta técnicas experimentales que utilizan imágenes térmicas en lugar de las clásicas con luz visible. A continuación, se ha implementado una aplicación en lenguaje C++ que sea capaz de reconocer a personas almacenadas en su base de datos leyendo directamente imágenes desde una webcam. Para realizar la aplicación, se ha utilizado una de las librerías más extendidas en cuanto a procesado de imágenes y visión artificial, OpenCV. Como IDE se ha escogido Visual Studio 2010, que cuenta con una versión gratuita para estudiantes. La técnica escogida para implementar la aplicación es la del PCA ya que es una técnica básica en el reconocimiento facial, y además sirve de base para soluciones mucho más complejas. Se han estudiado los fundamentos matemáticos de la técnica para entender cómo procesa la información y en qué se datos se basa para realizar el reconocimiento. Por último, se ha implementado un algoritmo de testeo para poder conocer la fiabilidad de la aplicación con varias bases de datos de imágenes faciales. De esta forma, se puede comprobar los puntos fuertes y débiles del PCA. ABSTRACT. This project deals with one of the most problematic areas of artificial intelligence, facial recognition. Something so simple for human as to recognize a familiar face becomes into complex algorithms and thousands of data processed in seconds. The project begins with a study of the state of the art of various face recognition techniques, from the most used and tested as PCA and LDA, to experimental techniques that use thermal images instead of the classic visible light images. Next, an application has been implemented in C + + language that is able to recognize people stored in a database reading images directly from a webcam. To make the application, it has used one of the most outstretched libraries in terms of image processing and computer vision, OpenCV. Visual Studio 2010 has been chosen as the IDE, which has a free student version. The technique chosen to implement the software is the PCA because it is a basic technique in face recognition, and also provides a basis for more complex solutions. The mathematical foundations of the technique have been studied to understand how it processes the information and which data are used to do the recognition. Finally, an algorithm for testing has been implemented to know the reliability of the application with multiple databases of facial images. In this way, the strengths and weaknesses of the PCA can be checked.