CETpD-UPC -Tech. Research Cen.for Dependency Care and Autonom Liviving
Total activity: 1278
Type
Research group
Type of group
Specific research center
Acronym
CETpD-UPC
Address
Rambla de l'Exposició, 61-69 Edifici NEAPOLIS Pl.2 Open in new window
City
Vilanova i la Geltrú
URL
http://www.epsevg.upc.edu/cetpd//index.php Open in new window
Objectives
CETpD's main research goal consists in the knowledge creation within the field of technology addressed to the dependency care area. In this way, the main interest is to improve the quality of life of people with dependency care assistance needs. Particularly, one of the main objectives relies on searching for new paradigms related to human movement analysis, usability and social robotics. CETpD directly cooperates with clinicians from several hospitals around Barcelona and some hospitals along Europe, developing research activities and projects in the dependency care area.

CETpD main research lines are:

Ambient Assisted Living and Pervasive Computing: create smart devices for both home and ambulatory monitoring of elderly people and patients with chronic diseases with tele-medicine and tele-care needs in order to assess gait, balance and falls. In this sense, CETpD has developed a wearable measurement unit for long-term monitoring of human movement. This measurement unit is being used to analyze human movement in the dependency care field.
Computational paradigms: develop soft-computing models, machine learning techniques and pervasive computing approaches addressed to the dependency care area.
Epidemiologic studies: CETpD performs, together with medical centers, clinical and epidemiologic studies on gait pathologies with the aim of knowing its causes and find new therapies that help to prevent its consequences in an effective way.
Social robotics: The priorities of this research line are three: (1) to develop new architectures of control and forms of signal processing which the robots allow to capture knowledge and being cognitive through the human-machine interaction; (2) to research in the more suitable forms of interaction, so they are motivating and satisfying for the user; and (3) to develop in an effective way robotic systems that are capable of supplying with personalised individual assistance to people with dependence (permanent, rehabilitation or convalescence).
Keywords
Inertial sensors, Intelligent algorithms, Motor symptoms, Parkinson's disease, REMPARK info, Smartphone, Wearable devices

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    Beyond cognition and affect: sensing the unconscious.  Open access

     Ivonin, Leonid; Huang-Ming, Chang; Diaz Boladeras, Marta; Català Mallofré, Andreu; Chen, Wei; Rauterberg, Mattias
    Behaviour & information technology
    DOI: 10.1080/0144929X.2014.912353
    Date of publication: 2014-05-09
    Journal article

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    In the past decade, research on human¿computer interaction has embraced psychophysiological user interfaces that enhance awareness of computers about conscious cognitive and affective states of users and increase their adaptive capabilities. Still, human experience is not limited to the levels of cognition and affect but extends further into the realm of universal instincts and innate behaviours that form the collective unconscious. Patterns of instinctual traits shape archetypes that represent images of the unconscious. This study investigated whether seven various archetypal experiences of users lead to recognisable patterns of physiological responses. More specifically, the potential of predicting the archetypal experiences by a computer from physiological data collected with wearable sensors was evaluated. The subjects were stimulated to feel the archetypal experiences and conscious emotions by means of film clips. The physiological data included measurements of cardiovascular and electrodermal activities. Statistical analysis indicated a significant relationship between the archetypes portrayed in the videos and the physiological responses. Data mining methods enabled us to create between-subject prediction models that were capable of classifying four archetypes with an accuracy of up to 57.1%. Further analysis suggested that classification performance could be improved up to 70.3% in the case of seven archetypes by using within-subject models.

    In the past decade, research on human–computer interaction has embraced psychophysiological user interfaces that enhance awareness of computers about conscious cognitive and affective states of users and increase their adaptive capabilities. Still, human experience is not limited to the levels of cognition and affect but extends further into the realm of universal instincts and innate behaviours that form the collective unconscious. Patterns of instinctual traits shape archetypes that represent images of the unconscious. This study investigated whether seven various archetypal experiences of users lead to recognisable patterns of physiological responses. More specifically, the potential of predicting the archetypal experiences by a computer from physiological data collected with wearable sensors was evaluated. The subjects were stimulated to feel the archetypal experiences and conscious emotions by means of film clips. The physiological data included measurements of cardiovascular and electrodermal activities. Statistical analysis indicated a significant relationship between the archetypes portrayed in the videos and the physiological responses. Data mining methods enabled us to create between-subject prediction models that were capable of classifying four archetypes with an accuracy of up to 57.1%. Further analysis suggested that classification performance could be improved up to 70.3% in the case of seven archetypes by using within-subject models.

  • Unspoken emotions in movies: The basis of emotion-driven storytelling systems

     Chang, Huang-ming; Ivonin, Leonid; Diaz Boladeras, Marta; Català Mallofré, Andreu
    Informatik-Spektrum
    DOI: 10.1007/s00287-014-0823-3
    Date of publication: 2014-07-28
    Journal article

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  • Quasi-digital front-ends for current measurement in integrated circuits with giant magnetoresistance technology

     De Marcellis, A.; Cubells Beltrán, M. Dolores; Reig Escriva, Abilio Càndid; Madrenas Boadas, Jordi; zadov, Boris; Paperno, Eugene; Cardoso, S.; Freitas, P.P.
    IET circuits, devices and systems
    Vol. 8, num. 4, p. 291-300
    DOI: 10.1049/iet-cds.2013.0348
    Date of publication: 2014-07-01
    Journal article

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    In this study, the authors report on two different electronic interfaces for low-power integrated circuits electric current monitoring through current-to-frequency (I-f) conversion schemes. This proposal displays the intrinsic advantages of the quasi-digital systems regarding direct interfacing and self-calibrating capabilities. In addition, as current-sensing devices, they have made use of the giant magnetoresistance (GMR) technology because of its high sensitivity and compatibility with standard complementary metal oxide semiconductor processes. Single elements and Wheatstone bridges based on spin-valves and magnetic tunnel junctions have been considered. In this sense, schematic-level simulations for integration in Austria Microsystems 0.35 mu m technology have been corroborated by means of experimental measurements with the help of printed circuit board prototypes and real GMR devices. Tables with relevant parameters (silicon area, power consumption, sensitivity etc.) have been constructed as practical tools for designers. Electric currents down to 2 mu A have been resolved in this way.

    In this study, the authors report on two different electronic interfaces for low-power integrated circuits electric current monitoring through current-to-frequency (I-f) conversion schemes. This proposal displays the intrinsic advantages of the quasi-digital systems regarding direct interfacing and self-calibrating capabilities. In addition, as current-sensing devices, they have made use of the giant magnetoresistance (GMR) technology because of its high sensitivity and compatibility with standard complementary metal oxide semiconductor processes. Single elements and Wheatstone bridges based on spin-valves and magnetic tunnel junctions have been considered. In this sense, schematic-level simulations for integration in Austria Microsystems 0.35 mu m technology have been corroborated by means of experimental measurements with the help of printed circuit board prototypes and real GMR devices. Tables with relevant parameters (silicon area, power consumption, sensitivity etc.) have been constructed as practical tools for designers. Electric currents down to 2 mu A have been resolved in this way.

  • Observing the use of an input device for rehabilitation purposes

     Manresa-Yee, Cristina; Ponsa Asensio, Pedro; Salinas, Iosune; Perales, Francisco J.; Negre, Francisca; Varona, Javier
    Behaviour & information technology
    Vol. 33, num. 3, p. 270-281
    DOI: 10.1080/0144929X.2013.795607
    Date of publication: 2014-02-26
    Journal article

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    We designed and developed a vision-based computer interface which works with head movements. The system was implemented in a centre for users with cerebral palsy and they used it in contexts related with recreation or with education. During this process, it was observed that the continued use of the interface with a set of training tasks may act as a physical and cognitive rehabilitation tool and complement users¿ rehabilitation therapy. We comment on five case studies of users who have worked with the interface for five months and whose qualitative outcomes, observed by the therapists who accompanied them, were positive; specifically there was improvement in work posture, head control, increased endurance, decreased involuntary movements and improved spatial orientation. The case studies also showed the need to supervise the users¿ work in order to achieve these aims, along with the importance of motivation and active, voluntary participation of users in the rehabilitation process.

  • Continuous Generalized Procrustes analysis

     Igual, Laura; Perez Sala, Xavier; Escalera, Sergio; Angulo Bahón, Cecilio; De La Torre, Fernando
    Pattern recognition
    Vol. 47, num. 2, p. 659-671
    DOI: 10.1016/j.patcog.2013.08.006
    Date of publication: 2014-02
    Journal article

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    Two-dimensional shape models have been successfully applied to solve many problems in computer vision, such as object tracking, recognition, and segmentation. Typically, 2D shape models are learned from a discrete set of image landmarks (corresponding to projection of 3D points of an object), after applying Generalized Procustes Analysis (GPA) to remove 2D rigid transformations. However, the standard GPA process suffers from three main limitations. Firstly, the 2D training samples do not necessarily cover a uniform sampling of all the 3D transformations of an object. This can bias the estimate of the shape model. Secondly, it can be computationally expensive to learn the shape model by sampling 3D transformations. Thirdly, standard GPA methods use only one reference shape, which can might be insufficient to capture large structural variability of some objects. To address these drawbacks, this paper proposes continuous generalized Procrustes analysis (CGPA). CGPA uses a continuous formulation that avoids the need to generate 2D projections from all the rigid 3D transformations. It builds an efficient (in space and time) non-biased 2D shape model from a set of 3D model of objects. A major challenge in CGPA is the need to integrate over the space of 3D rotations, especially when the rotations are parameterized with Euler angles. To address this problem, we introduce the use of the Haar measure. Finally, we extended CGPA to incorporate several reference shapes. Experimental results on synthetic and real experiments show the benefits of CGPA over GPA.

  • GSVM: An SVM for handling imbalanced accuracy between classes in bi-classification problems

     Gonzalez Abril, Luis; Núñez Castro, Haydemar; Angulo Bahón, Cecilio; Velasco, Francisco
    Applied soft computing
    Vol. 17, p. 23-31
    DOI: 10.1016/j.asoc.2013.12.013
    Date of publication: 2014-04
    Journal article

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    A new support vector machine, SVM, is introduced, called GSVM, which is specially designed for bi-classification problems where balanced accuracy between classes is the objective. Starting from a standard SVM, the GSVM is obtained from a low-cost post-processing strategy by modifying the initial bias. Thus, the bias for GSVM is calculated by moving the original bias in the SVM to improve the geometric mean between the true positive rate and the true negative rate. The proposed solution neither modifies the original optimization problem for SVM training, nor introduces new hyper-parameters. Experimentation carried out on a high number of databases (23) shows GSVM obtaining the desired balanced accuracy between classes. Furthermore, its performance improves well-known cost-sensitive schemes for SVM, without adding complexity or computational cost.

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    Mood boards as a universal tool for investigating emotional experience  Open access

     Huang-Ming, Chang; Diaz Boladeras, Marta; Català Mallofré, Andreu; Chen, Wei; Rauterberg, Mattias
    Lecture notes in computer science
    Vol. 8520 Design, User Experie, p. 220-231
    DOI: 10.1007/978-3-319-07638-6_22
    Date of publication: 2014-04-03
    Journal article

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    Emotion is an essential part of user experience. While researchers are striving for new research tools for evaluate emotional experiences in design, designers have been using experience-based tools for studying emotions in practice, such as mood boards. Mood boards were developed for communicating emotional qualities between designers and clients, but have not yet been considered as an evaluation tool for investigating emotional experience. In this study we examined whether design students and non-design students have similar criteria in evaluating these mood boards. The results showed that the inter-rater reliability among all participants were considerably high, which suggested that mood boards are potential to be used as an evaluation tool for research on emotion.

    Emotion is an essential part of user experience. While researchers are striving for new research tools for evaluate emotional experiences in design, designers have been using experience-based tools for studying emotions in practice, such as mood boards. Mood boards were developed for communicating emotional qualities between designers and clients, but have not yet been considered as an evaluation tool for investigating emotional experience. In this study we examined whether design students and non-design students have similar criteria in evaluating these mood boards. The results showed that the inter-rater reliability among all participants were considerably high, which suggested that mood boards are potential to be used as an evaluation tool for research on emotion.

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    Enacting archetypes in movies: grounding the unconscious mind in emotion-driven media  Open access

     Huang-Ming, Chang; Ivonin, Leonid; Diaz Boladeras, Marta; Català Mallofré, Andreu; Chen, Wei; Rauterberg, Mattias
    Digital creativity (Exeter)
    DOI: 10.1080/14626268.2014.939985
    Date of publication: 2014-08-13
    Journal article

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    The concept of emotion-driven media integrates affective computing into developing new types of digital media by including the human spectator as an essential part of the whole system. Enactive media, as a landmark in this direction, PROVIDES a theoretical basis that is rooted in the enactivist approach in cognitive science. Based on this thesis, it is required to establish a practical procedure for developing the media content through integrating psychological approaches. We demonstrate a systematic approach for developing the content for emotion-driven media. The theory of archetypes, one of the psychoanalytical approaches, was applied for editing movie clips as the media content, and coupled the content with emotional responses by using experimental psychological methodologies. The results showed that it is promising to utilise archetypal movie clips as the content of emotion-driven media and archetypal symbolism can be a useful resource for developing the content of media systems.

    The concept of emotion-driven media integrates affective computing into developing new types of digital media by including the human spectator as an essential part of the whole system. Enactive media, as a landmark in this direction, PROVIDES a theoretical basis that is rooted in the enactivist approach in cognitive science. Based on this thesis, it is required to establish a practical procedure for developing the media content through integrating psychological approaches. We demonstrate a systematic approach for developing the content for emotion-driven media. The theory of archetypes, one of the psychoanalytical approaches, was applied for editing movie clips as the media content, and coupled the content with emotional responses by using experimental psychological methodologies. The results showed that it is promising to utilise archetypal movie clips as the content of emotion-driven media and archetypal symbolism can be a useful resource for developing the content of media systems.

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    La usabilidad de las interfaces basadas en visión  Open access

     Manresa-Yee, Cristina; Amengual, Esperança; Ponsa Asensio, Pedro
    FAZ
    num. 7, p. 12-31
    Date of publication: 2014-07-24
    Journal article

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    Las interfaces basadas en visión hacen uso de gestos para la comunicación del usuario con el sistema interactivo sin la necesidad de dispositivos que requieran contacto físico. El modelado de gestos suele realizarse en laboratorios y es importante que se lleve a cabo la evaluación de su usabilidad, pero la gran diversidad de usos y aplicaciones de estas interfaces hace que resulte difícil decidir qué factores tener en cuenta cuando se mide la usabilidad. En este artículo se presenta una revisión de la literatura cuyo objetivo es clasificar i recopilar los factores y las métricas de usabilidad que se utilizan para validar las interfaces basadas en visión.

    Las interfaces basadas en visión hacen uso de gestos para la comunicación del usuario con el sistema interactivo sin la necesidad de dispositivos que requieran contacto físico. El modelado de gestos suele realizarse en laboratorios y es importante que se lleve a cabo la evaluación de su usabilidad, pero la gran diversidad de usos y aplicaciones de estas interfaces hace que resulte difícil decidir qué factores tener en cuenta cuando se mide la usabilidad. En este artículo se presenta una revisión de la literatura cuyo objetivo es clasificar i recopilar los factores y las métricas de usabilidad que se utilizan para validar las interfaces basadas en visión.

  • prórroga del TIN2010-20966-C02-02 - APRENDIZAJE AUTOMATICO DE CAPACIDADES SENSORIALES MEDIANTE MAQUINAS DE SOPORTE VECTORIAL

     Sanchez Soler, Monica; Ruiz Vegas, Francisco Javier; Prats Duaygues, Francesc; Aguado Chao, Juan Carlos; Sama Monsonis, Albert
    Competitive project

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    Human centred design considerations for connected health devices for the older adult  Open access

     Harte, Richard P.; Glynn, Liam G.; Broderick, Barry J.; Rodríguez Molinero, Alejandro; Baker, Paul M. A.; McGuiness, Bernadette; O'Sullivan, Leonard; Diaz Boladeras, Marta; Quinlan, Leo R.; ÓLaighin, Gearóid
    Journal of Personalized Medicine
    Vol. 4, num. 2, p. 245-281
    DOI: 10.3390/jpm4020245
    Date of publication: 2014-06-04
    Journal article

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    Connected health devices are generally designed for unsupervised use, by non-healthcare professionals, facilitating independent control of the individuals own healthcare. Older adults are major users of such devices and are a population significantly increasing in size. This group presents challenges due to the wide spectrum of capabilities and attitudes towards technology. The fit between capabilities of the user and demands of the device can be optimised in a process called Human Centred Design. Here we review examples of some connected health devices chosen by random selection, assess older adult known capabilities and attitudes and finally make analytical recommendations for design approaches and design specifications.

    Connected health devices are generally designed for unsupervised use, by non-healthcare professionals, facilitating independent control of the individuals own healthcare. Older adults are major users of such devices and are a population significantly increasing in size. This group presents challenges due to the wide spectrum of capabilities and attitudes towards technology. The fit between capabilities of the user and demands of the device can be optimised in a process called Human Centred Design. Here we review examples of some connected health devices chosen by random selection, assess older adult known capabilities and attitudes and finally make analytical recommendations for design approaches and design specifications.

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    Diseño centrado en el usuario para diseñadores industriales  Open access

     Ponsa Asensio, Pedro; Garvin, Kevin; González, Fernanda; Ruegger, Raíssa; Santos, Larissa; Granollers, Antoni; Vilanova Arbós, Ramón
    FAZ
    num. 7, p. 99-119
    Date of publication: 2014-07-24
    Journal article

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    La conexión entre metodologías de la interacción persona-ordenador con métodos tradicionales de diseño es presentada en el contexto del grado de ingeniería del diseño industrial y desarrollo del producto que se imparte en la Escuela Politécnica Superior de Ingeniería de Vilanova i la Geltrú. Un conjunto de asignaturas, un programa de movilidad internacional, profesorado especializado en diseño centrado en el usuario y expertos en entornos industriales y sociales facilitan esta relación. Este trabajo muestra un conjunto de estudios de caso seleccionados que proporciona las claves para la sinergia entre la expleriencia de usuario y el diseño de productos-servicios.

    La conexión entre metodologías de la interacción persona-ordenador con métodos tradicionales de diseño es presentada en el contexto del grado de ingeniería del diseño industrial y desarrollo del producto que se imparte en la Escuela Politécnica Superior de Ingeniería de Vilanova i la Geltrú. Un conjunto de asignaturas, un programa de movilidad internacional, profesorado especializado en diseño centrado en el usuario y expertos en entornos industriales y sociales facilitan esta relación. Este trabajo muestra un conjunto de estudios de caso seleccionados que proporciona las claves para la sinergia entre la experiencia de usuario y el diseño de productos-servicios.

  • Realistic model of compact VLSI FitzHugh-Nagumo oscillators

     Cosp Vilella, Jordi; Binczak, Stéphane; Madrenas Boadas, Jordi; Ruiz Fernández, Daniel
    International journal of electronics
    Vol. 101, num. 2, p. 220-230
    DOI: 10.1080/00207217.2013.780263
    Date of publication: 2014-02-01
    Journal article

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    In this article, we present a compact analogue VLSI implementation of the FitzHugh-Nagumo neuron model, intended to model large-scale, biologically plausible, oscillator networks. As the model requires a series resistor and a parallel capacitor with the inductor, which is the most complex part of the design, it is possible to greatly simplify the active inductor implementation compared to other implementations of this device as typically found in filters by allowing appreciable, but well modelled, nonidealities. We model and obtain the parameters of the inductor nonideal model as an inductance in series with a parasitic resistor and a second order low-pass filter with a large cut-off frequency. Post-layout simulations for a CMOS 0.35 m double-poly technology using the MOSFET Spice BSIM3v3 model confirm the proper behaviour of the design. © 2013 Taylor & Francis.

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    A survey on model based approaches for 2D and 3D visual human pose recovery  Open access

     Perez Sala, Xavier; Escalera, Sergio; Angulo Bahón, Cecilio; Gonzàlez, Jordi
    Sensors
    Vol. 14, num. 3, p. 4189-4210
    DOI: 10.3390/s140304189
    Date of publication: 2014-03-03
    Journal article

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    Human Pose Recovery has been studied in the field of Computer Vision for the last 40 years. Several approaches have been reported, and significant improvements have been obtained in both data representation and model design. However, the problem of Human Pose Recovery in uncontrolled environments is far from being solved. In this paper, we define a general taxonomy to group model based approaches for Human Pose Recovery, which is composed of five main modules: appearance, viewpoint, spatial relations, temporal consistence, and behavior. Subsequently, a methodological comparison is performed following the proposed taxonomy, evaluating current SoA approaches in the aforementioned five group categories. As a result of this comparison, we discuss the main advantages and drawbacks of the reviewed literature.

    Human Pose Recovery has been studied in the field of Computer Vision for the last 40 years. Several approaches have been reported, and significant improvements have been obtained in both data representation and model design. However, the problem of Human Pose Recovery in uncontrolled environments is far from being solved. In this paper, we define a general taxonomy to group model based approaches for Human Pose Recovery, which is composed of five main modules: appearance, viewpoint, spatial relations, temporal consistence, and behavior. Subsequently, a methodological comparison is performed following the proposed taxonomy, evaluating current SoA approaches in the aforementioned five group categories. As a result of this comparison, we discuss the main advantages and drawbacks of the reviewed literature.

  • Efficient multiprocessing architectures for Spiking Neural Network emulation based on configurable devices

     Sanchez Rivera, Giovanny
    Department of Electronic Engineering, Universitat Politècnica de Catalunya
    Theses

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    L'estudi de la dinàmica de les xarxes neuronals bio-inspirades ha permès als neurocientífics entendre alguns processos i estructures del cervell . Les implementacions electròniques d'aquestes xarxes neuronals són eines útils per dur a terme aquest tipus d'estudi . No obstant això, l'alta complexitat de les xarxes neuronals requereix d'una arquitectura apropiada que pugui simular aquest tipus de xarxes. Emular aquest tipus de xarxes en dispositius configurables és possible a causa del seu extraordinari desenvolupament respecte a la seva disponibilitat de recursos, velocitat i capacitat de reconfiguració (FPGAs ) .En aquesta tesi es proposa una arquitectura maquinari paral · lela i configurable per emular les complexes i realistes xarxes neuronals tipus spiking en temps real . S'han estudiat i analitzat alguns models de neurones tipus spiking rellevants i les seves implementacions en maquinari , amb la finalitat de crear una arquitectura que suporti la implementació d'aquests models de manera eficient .S'han tingut en compte diversos factors clau, incloent flexibilitat en la programació d'algorismes, processament d'alt rendiment, baix consum d'energia i àrea. S'han aplicat diverses tècniques en l'arquitectura desenvolupada amb el propòsit d'augmentar la seva capacitat de processament. Aquestes tècniques són: mapejat de temps a espai, virtualització de les neurones, mapeig flexible de neurones i sinapsis, modes d'execució, i aprenentatge específic, entre d'altres. A més, s'ha desenvolupat una unitat d'interfície de dades per tal de construir un sistema bio-inspirat, que pot processar informació sensorial del medi ambient. Aquest sistema basat en neurones tipus spiking combina implementacions analògiques i digitals. S'han desenvolupat diverses aplicacions usant aquest sistema com a prova de concepte, per tal de mostrar les capacitats de l'arquitectura proposada per al processament d'aquest tipus d'informació.

  • Contribución al análisis del movimiento humano aplicado a la identificación de posturas y bloqueos de la marcha en pacientes con Parkinson  Open access

     Rodriguez Martin, Daniel Manuel
    Universitat Politècnica de Catalunya
    Theses

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    La siguiente disertación presenta las aportaciones del autor en el campo de la monitorización del movimiento humano y, especialmente, en la enfermedad del Parkinson. Las recientes tecnologías han permitido desarrollar sensores inerciales de tamaño muy reducido para monitorizar el movimiento humano. En consecuencia, el uso de las llamadas unidades de medida inercial, que consisten en unos dispositivos de pequeño tamaño capaces de medir el movimiento, se ha extendido ampliamente empleándose, entre otros, en campos como la medicina, el deporte, la automoción o los videojuegos. En la primera parte de la presente tesis, se describe el desarrollo de una unidad de medida inercial capaz de adquirir datos con una larga autonomía. La principal novedad aportada consiste en la posibilidad de implementar clasificadores basados en inteligencia artificial en tiempo real a través de un hardware y un firmware diseñados específicamente para que el sistema inercial sea flexible y capaz de implementar las dos operaciones. Esta herramienta se ha validado en diferentes proyectos europeos y diferentes trabajos llevados a cabo en el Centro de Estudios Tecnológicos para la Atención de la Dependencia y la Vida Autónoma de la Universidad Politécnica de Catalunya (CETpD-UPC)En la segunda parte de la tesis se describen dos algoritmos para identificar diferentes tipos de posturas. Los datos empleados para poder desarrollar los algoritmos se han adquirido con el sistema inercial presentado en la primera parte de la tesis. Los algoritmos desarrollados se han validado en personas sanas y en pacientes con la enfermedad del Parkinson. El algoritmo se focaliza en la detección de posturas con un único sistema inercial localizado en la cintura, consiguiendo una mayor comodidad para los usuarios. Una aportación clave es la metodología ofrecida para poder detectar transiciones posturales (movimiento para pasar de una postura a otra) a través de `Máquinas de vectores soporte¿, permitiendo tanto distinguirlas como detectarlas. La detección de transiciones posturales se integra en un sistema jerárquico de clasificación, al cual se añade un detector de actividades básicas donde se identifican posturas estáticas como estar sentado, de pie, o tumbado, y posturas dinámicas, como caminar. En la parte final de la tesis se presenta una aportación a la identificación de uno de los síntomas de la enfermedad del Parkinson más incapacitantes, el bloqueo de la marcha. El algoritmo de posturas se aplica en señales captadas por la unidad inercial descrita en la primera parta de la tesis para complementar a los algoritmos actuales de detección de bloqueos de la marcha. Además, se demuestra cómo los valores de evaluación del algoritmo de detección del bloqueo de la marcha mejoran al aplicar el algoritmo de posturas. De esta forma, se contextualiza el algoritmo, pudiendo discriminar aquellos episodios detectados provocados en situaciones donde no es posible que ocurra un episodio de bloqueo de la marcha.

    The following dissertation presents the contributions of the author in the field of human movement analysis and, specifically, in Parkinson's disease. Recent technologies have allowed developing reduced inertial sensors capable of monitoring human movement. This, along with the reduced prices of these inertial sensors, the so-called inertial measurement units, which consists in small devices capable to measure movement by means of inertial sensors, have widely spread. Inertial measurement units have been employed among others, in fields such as medicine, sports, automotive and gaming. In the first part of the present thesis, a wearable long-term monitoring inertial measurement unit is presented as the first main contribution in human movement analysis. The unit is capable of acquiring data and provides the possibility of implementing artificial intelligence-based classifiers in real time. A specific hardware and firmware has been developed in order to implement both operations. This tool has been validated in different European projects and studies carried out in the Technical Research Centre for Dependency Care and Autonomous Living of the Universitat Politècnica de Catalunya (CETpD-UPC). The second part of the thesis addresses the analysis of human posture based on accelerometry measurements. To this end, data acquired from the inertial system described at the first part of the thesis have been used. Two methodologies are presented that have been validated on healthy people and patients with Parkinson's disease. The algorithms developed are focused on the detection of positions with a single inertial system located at the waist thereby achieving an enhanced comfort and acceptance by the users. A key contribution is the methodology provided to detect postural transitions, which consist in the movement performed to achieve a position from another one. The algorithm is based on support vector machines applied to the inertial data coming from a single measurement unit. Basic activity recognition is performed recognizing static postures such as sitting, standing, or lying with a hierarchical classification system. Moreover, dynamic postures such as walking and different postural transitions are also recognized. Finally, the posture detection methodologies are employed to enhance the identification of one of the most annoying symptoms of Parkinson's disease, the so-called Freezing of Gait. This contribution relies on the posture algorithm which has been validated in Parkinson's disease patients. Furthermore, it is shown how the introduction of the posture detection improves the evaluation values of the FOG algorithms

    La siguiente disertación presenta las aportaciones del autor en el campo de la monitorización del movimiento humano y, especialmente, en la enfermedad del Parkinson. Las recientes tecnologías han permitido desarrollar sensores inerciales de tamaño muy reducido para monitorizar el movimiento humano. Estos sensores se emplean en las llamadas unidades de medida inercial, que son unos dispositivos de pequeño tamaño capaces de medir el movimiento, se ha extendido ampliamente empleándose, entre otros, en campos como la medicina, el deporte, la automoción o los videojuegos. En la primera parte de la presente tesis, se describe el desarrollo de una unidad de medida inercial optimizada para realizar la adquisición y el tratamiento de los datos con un mínimo consumo y, de esa forma, conseguir una larga autonomía. La principal novedad aportada consiste en la posibilidad de implementar en tiempo real clasificadores basados en inteligencia artificial a través de un hardware y un firmware diseñados específicamente para que el sistema inercial sea flexible y capaz de implementar las dos operaciones, captura de datos y ejecución de algoritmos. Esta herramienta se ha validado en diferentes proyectos europeos y diferentes trabajos llevados a cabo en el Centro de Estudios Tecnológicos para la Atención de la Dependencia y la Vida Autónoma de la Universidad Politécnica de Catalunya (CETpDUPC). En la segunda parte de la tesis se describen dos algoritmos para identificar diferentes tipos de posturas. Los datos empleados para poder desarrollar los algoritmos se han adquirido con el sistema inercial presentado en la primera parte de la tesis. Los algoritmos desarrollados se han validado en personas sanas y en pacientes con la enfermedad del Parkinson. Estos algoritmos se focalizan en la detección de posturas con un único sistema inercial localizado en la cintura. Esta localización permite una mayor comodidad para los usuarios, entre otras ventajas. Una aportación importante es la metodología utilizada para poder detectar transiciones posturales (movimiento para pasar de una postura a otra). Se ha empleado el paradigma de las máquinas de vectores soporte para poder distinguir las diferentes posturas del usuario o paciente. La detección de transiciones posturales se integra en un sistema jerárquico de clasificación, al cual se añade un detector de actividades básicas donde se identifican posturas estáticas, como estar sentado, de pie, o tumbado, y posturas dinámicas, como caminar. En la parte final de la tesis se presenta una aportación a la identificación de uno de los síntomas de la enfermedad del Parkinson más incapacitantes: el bloqueo de la marcha. El algoritmo de posturas se aplica en señales captadas por la unidad inercial descrita en la primera parta de la tesis para complementar a los algoritmos actuales de detección de bloqueos de la marcha. Además, se demuestra cómo los valores de evaluación del algoritmo de detección del bloqueo de la marcha mejoran al aplicar el algoritmo de posturas. De esta forma, el nuevo algoritmo contextualiza la detección del bloqueo de la marcha, omitiendo los casos positivos que ocurran en situaciones donde no es posible que un bloqueo de la marcha ocurra.

  • Emotions in Archetypal Media Content

     Huang-Ming, Chang
    Eindhoven University of Technology
    Theses

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    Emotion is an intriguing and mysterious psychological phenomenon. While everyone seems to know what it is, researchers have not yet come to consensus on its definition, and many questions still remain unanswered. While the nature of emotion is yet to discover, the design community has noticed its importance, and poses the challenge of how emotion could inform design. We see the necessity to follow the state of the art in psychology and initiate the undertaking by exploring the emotional qualities in various types of media content. The first part of this thesis aims at constructing a theoretical framework. Recent years have seen empirical studies suggest that emotion could be unconscious. While this is to be further justified, scientists are motivated to reconsider current theories of emotion to account for this phenomenon. In light of this, we integrate these studies about unconscious emotion into our literature review. An overview from theory to practice is illustrated to provide a reference for viewing the current states in application domains, such as affective computing and emotional design. This review offers a holistic understanding about emotion from various perspectives, which allow us to look for new directions in future studies. Based on our review, we see a promising direction by applying psychoanalysis methods to analyze the media content as affective stimuli, and these stimuli can be evaluated by using quantitative measures to investigate the connection between the content and the corresponding emotions. The analysis on the media content is based on a psychoanalysis theory¿the theory of archetypes¿proposed by Carl Jung. He argues that there exists a universal pattern in humans¿ unconscious thoughts, which can be manifested as symbolic content in various forms of narratives, such as myth and fairy tales. Today, this archetypal symbolic content can be seen in modern media, particularly in movies. By applying the Jungian approach, we analyzed the symbolic meaning in movie scenes and edit these feature scenes into a collection of archetypal media content, which serve as the experimental materials for later explorations. In the second part of this thesis, we present three experimental studies that aim at determining if archetypal media content can be differentiated based on emotional responses. We adopted the psychoanalytical approach described earlier to collect feature scenes in movies as archetypal media content. Meanwhile, affective stimuli of explicit emotions are also included as benchmarks for comparison, such as sadness and joy.

  • Proposal and development of a highly modular and scalable self-adaptive hardware architecture with parallel processing capability  Open access

     Soto Vargas, Javier Evandro
    Department of Electronic Engineering, Universitat Politècnica de Catalunya
    Theses

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    Esta tesis doctoral describe una arquitectura de hardware auto-adaptable novedosa y no convencional con capacidad de procesamiento en paralelo. Por razones de escalabilidad, esta arquitectura bioinspirada está basada en una matriz regular de células homogéneas. La arquitectura propuesta es programable, e implementa de manera distribuida diversas capacidades auto-adaptables incluyendo el auto-emplazamiento y auto-enrutamiento, los cuales debido a su diseño intrínseco, permiten el desarrollo de sistemas reconfigurables en tiempo de ejecución, así como de sistemas auto-reparables y/o con capacidades de tolerancia a fallos. La implementación física de esta arquitectura esta compuesta de dos capas, que incluyen células interconectadas en el primer nivel y matrices de conmutación y pines en el segundo nivel. La célula es el elemento básico de la arquitectura propuesta. Cualquier aplicación que se quiera programar en el sistema debe estar organizada en componentes, donde cada componente está compuesto por una o más células interconectadas. La interconexión de células dentro de un componente es realizado en el mismo nivel de la matriz de células, mientras que la interconexión de componentes es realizada en la segunda capa. Adicionalmente, se definen dos capas conceptuales que son usadas con propósitos organizativos en aplicaciones de propósito general, estas son: el SANE y el SANE-assembly (o conjunto de SANEs). La entidad auto-adaptable interconectada o SANE está compuesta por un grupo de componentes. Este es el sistema de computación auto-adaptable básico, el cual tiene la habilidad de monitorizar su entorno local y su proceso de computación interno.Las capacidades de procesamiento de la célula están incluidas en su unidad funcional (FU). Esta puede ser definida como un multicomputador configurable con cuatro núcleos, los cuales son agrupados o no dependiendo del modo de configuración. La FU tiene doce modos de configuración programables, por lo que cada célula permite seleccionar entre uno y cuatro procesadores trabajando en paralelo con diversas capacidades en las memorias de programa y datos. Las capacidades auto-adaptables de la célula son ejecutadas principalmente por la unidad de configuración de la célula (CCU). El algoritmo de auto-emplazamiento es el encargado de encontrar la posición mas adecuada dentro de la matriz de células para insertar la nueva célula de un componente. El algoritmo de auto-enrutamiento permite interconectar los puertos de las FU de dos células. Los procesos de auto-emplazamiento y auto-enrutamiento permiten realizar en tiempo real cambios funcionales complejos; estos procesos dotan al sistema de una mayor funcionalidad, permitiendo que el sistema cambie por si mismo, lo que permite la implementación de la auto-configuración en tiempo real, sin la necesidad de ningún gestor de configuración.La arquitectura propuesta incluye dos mecanismos de tolerancia a fallos. Uno de estos es una técnica escalonada y dinámica de tolerancia a fallos, que tiene la habilidad de crear y eliminar copias redundantes de la unidad funcional (o de cómputo) de una aplicación específica. El otro mecanismo de tolerancia a fallos es el Sistema de Tolerancia a Fallos dedicado o estático. Este provee capacidades de procesamiento redundante que están en funcionamiento continuamente. Cuando un fallo en la ejecución de un programa es detectado, los procesadores de la célula son detenidos y los procesos de auto-eliminación y auto-replicación se inician para la célula (o células) implicada en el fallo. Se desarrolló un prototipo basado en FPGAs y una herramienta de software para comprobar la funcionalidad del sistema. El prototipo incluye todas las características de los sistemas auto-adaptable descritas en este trabajo. El SANE Project developer (SPD) es un ambiente integrado de desarrollo (IDE) que permite generar y descargar la memoria de inicialización de datos para el Microprocesador de Control dentro del prototipo.

    This dissertation describes a novel unconventional self-adaptive hardware architecture with capacity for parallel processing. For scalability issues, this bioinspired architecture is based on a regular array of homogeneous cells. The proposed programmable architecture implements in a distributed way self-adaptive capabilities including self-placement and self-routing which, due to its intrinsic design, enable the development of systems with runtime reconfiguration, self-repair and/or fault tolerance capabilities. The physical implementation of this architecture is composed of two-layers, interconnected cells in the first level and interconnected switch and pin matrices in the second level. The cell is the basic element of the proposed self-adaptive architecture. Any application scheduled to the system has to be organized in components, where each component is composed by one or more interconnected cells. The interconnection of cells inside a component is made at cell level (first layer), while the physical interconnections of components are made in the second layer. Additionally, two layers are defined as conceptual organization for the implementation of general purpose applications: the SANE and the SANE assembly. The Self-Adaptive Networked Entity (SANE) is composed by a group of components. This is the basic self-adaptive computing system. It has the ability to monitor its local environment and its internal computation process. The SANE-Assembly (SANE-ASM) is composed by a group of interconnected SANEs. The processing capabilities of the cell are included in its Functional Unit (FU), which can be described as a four-core configurable multicomputer. The FU includes twelve programmable configuration modes, i.e., each cell permits to select from one to four processors working in parallel, with different size of program and data memories. The self-adaptive capabilities of the cell are executed mainly by the Cell Configuration Unit (CCU). The self-placement algorithm is responsible for finding out the most suitable position in the cell array to insert the new cell of a component. The self-routing algorithm permits interconnecting the ports of the FU of two cells through the cell ports. The self-placement and self-routing processes allow for performing complex functionality changes in real time, these processes endow the system with enhanced functionality, enabling the system to change itself, this allows for the implementation of run-time self-configuration, without the need for any configuration manager. The architecture proposed includes two mechanisms of fault tolerance. One of these is the Dynamic Fault Tolerance Scaling Technique, that has the ability to create and eliminate the redundant copies of the functional section of a specific application. The other mechanism of fault tolerance is a dedicated or static Fault Tolerance System. It provides redundant processing capabilities that are working continuously. When a failure in the execution of a program is detected, the processors of the cell are stopped and the self-elimination and self-replication processes start for the cell (or cells) involved in the failure. An FPGA-based prototype and a software tool have been built for demonstration purposes. The prototype includes all the self-adaptive capabilities described in this dissertation. With the purpose of having a complete development system, the software tool SANE Project Developer (SPD) has been implemented. The SPD is an Integrated Development Environment (IDE) that allows generating the memory initialization data for the control microprocessor inside the prototype.

    Esta tesis doctoral describe una arquitectura de hardware auto-adaptable novedosa y no convencional con capacidad de procesamiento en paralelo. Por razones de escalabilidad, esta arquitectura bioinspirada está basada en una matriz regular de células homogéneas. La arquitectura propuesta es programable, e implementa de manera distribuida diversas capacidades auto-adaptables incluyendo el auto-emplazamiento y auto-enrutamiento, los cuales debido a su diseño intrínseco, permiten el desarrollo de sistemas reconfigurables en tiempo de ejecución, así como de sistemas autoreparables y/o con capacidades de tolerancia a fallos. La implementación física de esta arquitectura esta compuesta de dos capas, que incluyen células interconectadas en el primer nivel y matrices de conmutación y pines en el segundo nivel. La célula es el elemento básico de la arquitectura propuesta. Cualquier aplicación que se quiera programar en el sistema debe estar organizada en componentes, donde cada componente está compuesto por una o más células interconectadas. La interconexión de células dentro de un componente es realizado en el mismo nivel de la matriz de células, mientras que la interconexión de componentes es realizada en la segunda capa. Adicionalmente, se definen dos capas conceptuales que son usadas con propósitos organizativos en aplicaciones de propósito general, estas son: el SANE y el SANE-assembly (o conjunto de SANEs). La entidad auto-adaptable interconectada o SANE está compuesta por un grupo de componentes. Este es el sistema de computación auto-adaptable básico, el cual tiene la habilidad de monitorizar su entorno local y su proceso de computación interno. Las capacidades de procesamiento de la célula están incluidas en su unidad funcional (FU). Esta puede ser definida como un multicomputador configurable con cuatro núcleos, los cuales son agrupados o no dependiendo del modo de configuración. La FU tiene doce modos de configuración programables, por lo que cada célula permite seleccionar entre uno y cuatro procesadores trabajando en paralelo con diversas capacidades en las memorias de programa y datos. Las capacidades auto-adaptables de la célula son ejecutadas principalmente por la unidad de configuración de la célula (CCU). El algoritmo de auto-emplazamiento es el encargado de encontrar la posición mas adecuada dentro de la matriz de células para insertar la nueva célula de un componente. El algoritmo de auto-enrutamiento permite interconectar los puertos de las FU de dos células. Los procesos de auto-emplazamiento y auto-enrutamiento permiten realizar en tiempo real cambios funcionales complejos; estos procesos dotan al sistema de una mayor funcionalidad, permitiendo que el sistema cambie por si mismo, lo que permite la implementación de la auto-configuración en tiempo real, sin la necesidad de ningún gestor de configuración. La arquitectura propuesta incluye dos mecanismos de tolerancia a fallos. Uno de estos es una técnica escalonada y dinámica de tolerancia a fallos, que tiene la habilidad de crear y eliminar copias redundantes de la unidad funcional (o de cómputo) de una aplicación específica. El otro mecanismo de tolerancia a fallos es el Sistema de Tolerancia a Fallos dedicado o estático. Este provee capacidades de procesamiento redundante que están en funcionamiento continuamente. Cuando un fallo en la ejecución de un programa es detectado, los procesadores de la célula son detenidos y los procesos de auto-eliminación y auto-replicación se inician para la célula (o células) implicada en el fallo. Se desarrolló un prototipo basado en FPGAs y una herramienta de software para comprobar la funcionalidad del sistema. El prototipo incluye todas las características de los sistemas auto-adaptable descritas en este trabajo. El SANE Project developer (SPD) es un ambiente integrado de desarrollo (IDE) que permite generar y descargar la memoria de inicialización de datos para el Microprocesador de Control dentro del prototipo.

  • Robust video stabilization based on motion intention for low-cost micro aerial vehicles

     Aguilar, Wilbert; Angulo Bahón, Cecilio
    International Multi-Conference on Systems, Signals and Devices
    p. 1-6
    Presentation's date: 2014-02-12
    Presentation of work at congresses

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    Currently, different hand-held devices as domestic cameras, smart-phones, tablets, or on-board cameras for robots are becoming popular for video capturing. A main concern with these gadgets is undesired movement between consecutive frames. Video stabilization is a technique with increasing impact for solving this problem. In this paper, a proposal is introduced for robust video stabilization, in particular for on-board cameras in micro aerial vehicles. It is based on a combination of the RANSAC (RANdom SAmple Consensus) algorithm and gray level differences as cost function for local motion parameter estimation, as well as a low-pass filter for global motion smoothing. Experimentation will illustrate about of the robustness proposed solution.

    Currently, different hand-held devices as domestic cameras, smart-phones, tablets, or on-board cameras for robots are becoming popular for video capturing. A main concern with these gadgets is undesired movement between consecutive frames. Video stabilization is a technique with increasing impact for solving this problem. In this paper, a proposal is introduced for robust video stabilization, in particular for on-board cameras in micro aerial vehicles. It is based on a combination of the RANSAC (RANdom SAmple Consensus) algorithm and gray level differences as cost function for local motion parameter estimation, as well as a low-pass filter for global motion smoothing. Experimentation will illustrate about of the robustness proposed solution.

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    Robotics@Montserrat: A case of Learning through robotics community in a primary and secondary school  Open access

     Sans-Cope, Olga; Barco, Alex; Albo Canals, Jordi; Diaz Boladeras, Marta; Angulo Bahón, Cecilio
    Child-Robot Interaction Workshop at Interaction Design and Children Conference
    p. 1-5
    Presentation's date: 2014-06-17
    Presentation of work at congresses

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    Nowadays is well known that the learning of STEM (science, technology, engineering, and mathematics) can benefit from using Robotics technologies. Furthermore, robot-based educational activities can enhance not only the acquirement of concepts in other fields (e.g. literature, history) but even improve children emotional and social development. This paper describes how robotics has been introduced transversally at all k12 level in the school Montserrat in Barcelona, Spain. The infrastructure to support the program, the planning of the activities and research studies, a classification of these activities based on the children-robot interaction modality, and the details of some examples are described and discussed.

    Nowadays is well known that the learning of STEM (science, technology, engineering, and mathematics) can benefit from using Robotics technologies. Furthermore, robot-based educational activities can enhance not only the acquirement of concepts in other fields (e.g. literature, history) but even improve children emotional and social development. This paper describes how robotics has been introduced transversally at all k12 level in the school Montserrat in Barcelona, Spain. The infrastructure to support the program, the planning of the activities and research studies, a classification of these activities based on the children-robot interaction modality, and the details of some examples are described and discussed.

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    Develoment of an inverse model for honing processes by means of neural networks  Open access

     Sivatte Adroer, Maurici; Llanas Parra, Francesc Xavier; Buj Corral, Irene; Vivancos Calvet, Joan
    International Reseach/Expert Conference "Trends in the Development of Machinery and Associated Technology"
    p. 9-12
    Presentation's date: 2014-09-11
    Presentation of work at congresses

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    In a previous paper, artificial neural networks were employed for modelling average roughness Ra in rough honing processes as a function of process variables, namely grain size, density, linear speed, tangential speed and pressure, by means of the direct problem. In addition, neural network model was compared to statistical models for modelling roughness. In the present paper the inverse problem was studied and analyzed by means of neural networks, in which given a certain average roughness Ra value, the model predicts process variables to be employed. This is not possible with statistical models. Two different approaches were considered: use of a single network or use of five networks.

    In a previous paper, artificial neural networks were employed for modelling average roughness Ra in rough honing processes as a function of process variables, namely grain size, density, linear speed, tangential speed and pressure, by means of the direct problem. In addition, neural network model was compared to statistical models for modelling roughness. In the present paper the inverse problem was studied and analyzed by means of neural networks, in which given a certain average roughness Ra value, the model predicts process variables to be employed. This is not possible with statistical models. Two different approaches were considered: use of a single network or use of five networks.

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    Estabilización de vídeo en micro vehículos aéreos y su aplicación en la detección de caras  Open access

     Aguilar, Wilbert; Angulo Bahón, Cecilio
    Congreso de Ciencia y Tecnología
    p. 155-160
    Presentation's date: 2014-05
    Presentation of work at congresses

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    Actualmente, los vehículos aéreos de micros escala (MAVs) se han tornado populares para múltiples aplicaciones como rescate, vigilancia, mapeo, entre otras. Para todos los casos, es necesario un óptimo desempeño de los vídeos capturados a bordo, y uno de los principales problemas constituyen los movimientos indeseados entre fotogramas consecutivos. Para solventar esta problemática existes diferentes enfoques que, aplicados a post-procesamiento, consiguen una estabilización robusta en la imagen. Sin embargo, muy pocos algoritmos son capaces de ser aplicados en tiempo real. En este artículo se presenta un nuevo enfoque que puede ser implementado en tiempo real sin que se generen movimientos falsos. Nuestra propuesta usa una combinación de un filtro pasabajos, y la información de la acción de control para la estimación de la intención de movimiento. Adicionalmente, se presenta la aplicación de nuestra propuesta en el algoritmo de detección de caras, en el cual, la robustez se incrementa al ser implementado a partir de la secuencia estable de vídeo.

    Actualmente, los vehículos aéreos de micros escala (MAVs) se han tornado populares para múltiples aplicaciones como rescate, vigilancia, mapeo, entre otras. Para todos los casos, es necesario un óptimo desempeño de los vídeos capturados a bordo, y uno de los principales problemas constituyen los movimientos indeseados entre fotogramas consecutivos. Para solventar esta problemática existes diferentes enfoques que, aplicados a post-procesamiento, consiguen una estabilización robusta en la imagen. Sin embargo, muy pocos algoritmos son capaces de ser aplicados en tiempo real. En este artículo se presenta un nuevo enfoque que puede ser implementado en tiempo real sin que se generen movimientos falsos. Nuestra propuesta usa una combinación de un filtro pasabajos, y la información de la acción de control para la estimación de la intención de movimiento. Adicionalmente, se presenta la aplicación de nuestra propuesta en el algoritmo de detección de caras, en el cual, la robustez se incrementa al ser implementado a partir de la secuencia estable de vídeo.

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    Control autónomo de cuadricópteros para seguimiento de trayectorias  Open access

     Aguilar, Wilbert; Costa Castelló, Ramon; Angulo Bahón, Cecilio; Molina, Luis
    Congreso de Ciencia y Tecnología
    p. 140-144
    Presentation's date: 2014-05
    Presentation of work at congresses

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    El presente artículo técnico describe brevemente la propuesta de solución al control autónomo del seguimiento de trayectoria en el plano XY para el vehículo cuatrirrotor, como parte de la primer etapa del Concurso de Ingeniería de Control 2013 organizado por el Comité Español de Automática. El vehículo cuatrirrotor es el AR.Drone 1.0 de la empresa Parrot cuyo comportamiento es no lineal. La propuesta incluye modelado del sistema, diseño del controlador, planificador y simulación de los resultados.

    El presente artículo técnico describe brevemente la propuesta de solución al control autónomo del seguimiento de trayectoria en el plano XY para el vehículo cuatrirrotor, como parte de la primer etapa del Concurso de Ingeniería de Control 2013 organizado por el Comité Español de Automática. El vehículo cuatrirrotor es el AR.Drone 1.0 de la empresa Parrot cuyo comportamiento es no lineal. La propuesta incluye modelado del sistema, diseño del controlador, planificador y simulación de los resultados.

  • Access to the full text
    A week-long study on Robot-Visitors Spatial Relationships during Guidance in a Sciences Museum  Open access

     Diaz Boladeras, Marta; Paillacho, Dennys; Angulo Bahón, Cecilio; Torres, Oriol; González, Jonathan; Albo Canals, Jordi
    ACM/IEEE International Conference on Human-Robot Interaction
    p. 152-153
    DOI: 10.1145/2559636.2559797
    Presentation's date: 2014-03
    Presentation of work at congresses

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    In order to observe spatial relationships in social human-robot interactions, a eld trial was carried out within the CosmoCaixa Science Museum in Barcelona. The follow me episodes studied showed that the space congurations formed by guide and visitors walking together did not always tthe robot social affordances and navigation requirements to perform the guidance successfully, thus additional communication prompts are considered to regulate effectively the walking together and follow me behaviors.

    In order to observe spatial relationships in social human-robot interactions, a eld trial was carried out within the CosmoCaixa Science Museum in Barcelona. The follow me episodes studied showed that the space con gurations formed by guide and visitors walking together did not always tthe robot social affordances and navigation requirements to perform the guidance successfully, thus additional communication prompts are considered to regulate effectively the walking together and follow me behaviors.

  • Observation of chaotic behavior in automatic tuning loops for continuous-time filters

     Martínez García, Herminio; Cosp Vilella, Jordi; Manzanares Brotons, Manuel
    IEEE International Midwest Symposium on Circuits and Systems
    p. 742-745
    DOI: 10.1109/MWSCAS.2013.6674756
    Presentation's date: 2014-08
    Presentation of work at congresses

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    he appropriate linear dynamic modeling of continuous-time filters (CTFs) with automatic tuning loops should be obtained to assure stability in case an improved design of the loop controllers is to be carried out. With this aim, starting from a general and systematic analysis in order to obtain an equivalent small-signal linearized incremental model, from which transfer functions between output variables and control voltages are derived, the subsequent design of compensated loops with enhanced stability and dynamic performance is required. This systematic procedure allows obtaining improved controllers for the two involved control loops. However, CTFs with automatic tuning loops are nonlinear feedback systems with potential instability. What is more, nonlinear phenomena, which cannot be predicted by a design-oriented small signal modeling approach, are observed in this kind of tuning systems. The purpose of this work is to highlight that when control parameters are varied, the system could present different kinds of dynamical nonlinear phenomena such as bifurcations and chaotic behavior, which cannot be predicted by the small signal design-oriented model.

    he appropriate linear dynamic modeling of continuous-time filters (CTFs) with automatic tuning loops should be obtained to assure stability in case an improved design of the loop controllers is to be carried out. With this aim, starting from a general and systematic analysis in order to obtain an equivalent small-signal linearized incremental model, from which transfer functions between output variables and control voltages are derived, the subsequent design of compensated loops with enhanced stability and dynamic performance is required. This systematic procedure allows obtaining improved controllers for the two involved control loops. However, CTFs with automatic tuning loops are nonlinear feedback systems with potential instability. What is more, nonlinear phenomena, which cannot be predicted by a design-oriented small signal modeling approach, are observed in this kind of tuning systems. The purpose of this work is to highlight that when control parameters are varied, the system could present different kinds of dynamical nonlinear phenomena such as bifurcations and chaotic behavior, which cannot be predicted by the small signal design-oriented model.

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    From mythology to psychology: Identifying archetypal symbols in movies  Open access

     Diaz Boladeras, Marta; Català Mallofré, Andreu; Chen, Wei; Rauterberg, Mattias; Ivonin, Leonid; Huang-Ming, Chang
    Technoetic arts: a journal of speculative research
    Vol. 11, num. 2, p. 99-113
    DOI: 10.1386/tear.11.2.99_1
    Date of publication: 2013-09-06
    Journal article

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    In this article, we introduce the theory of archetype, which explains the connection between ancient myths and the human mind. Based on the assumption that archetypes are in the deepest level of human mind, we propose that archetypal symbolism is a kind of knowledge that supports the cognitive process for creating subjective world-view towards the physical world we live in. According to archetypal symbolism, we conducted an empirical study to identify archetypal symbols in modern movies. A new collection of movie clips was developed to represent eight essential archetypes: anima, animus, mentor, mother, shadow, hero¿s departure, hero¿s initiation and hero¿s return, which can be used in future studies on human emotion. In order to investigate the emotions towards these archetypal symbols, we provide suggestions from the psychological point of view. The present study demonstrates how to identify symbolic meanings in movies, and indicates a new direction for future studies in psychology.

    In this article, we introduce the theory of archetype, which explains the connection between ancient myths and the human mind. Based on the assumption that archetypes are in the deepest level of human mind, we propose that archetypal symbolism is a kind of knowledge that supports the cognitive process for creating subjective world-view towards the physical world we live in. According to archetypal symbolism, we conducted an empirical study to identify archetypal symbols in modern movies. A new collection of movie clips was developed to represent eight essential archetypes: anima, animus, mentor, mother, shadow, hero’s departure, hero’s initiation and hero’s return, which can be used in future studies on human emotion. In order to investigate the emotions towards these archetypal symbols, we provide suggestions from the psychological point of view. The present study demonstrates how to identify symbolic meanings in movies, and indicates a new direction for future studies in psychology.

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    Experiencing the world with archetypal symbols: A new form of aesthetics.  Open access

     Huang-Ming, Chang; Ivonin, Leonid; Diaz Boladeras, Marta; Català Mallofré, Andreu; Chen, Wei; Rauterberg, Mattias
    Lecture notes in computer science
    Vol. 8028 Distributed, Ambient, p. 205-214
    DOI: 10.1007/978-3-642-39351-8_23
    Date of publication: 2013-09-04
    Journal article

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    According to the theories of symbolic interactionism, phenomenology of perception and archetypes, we argue that symbols play the key role in translating the information from the physical world to the human experience, and archetypes are the universal knowledge of cognition that generates the background of human experience (the life-world). Therefore, we propose a conceptual framework that depicts how people experience the world with symbols, and how archetypes relate the deepest level of human experience. This framework indicates a new direction of research on memory and emotion, and also suggests that archetypal symbolism can be a new resource of aesthetic experience design.

    According to the theories of symbolic interactionism, phenomenology of perception and archetypes, we argue that symbols play the key role in translating the information from the physical world to the human experience, and archetypes are the universal knowledge of cognition that generates the background of human experience (the life-world). Therefore, we propose a conceptual framework that depicts how people experience the world with symbols, and how archetypes relate the deepest level of human experience. This framework indicates a new direction of research on memory and emotion, and also suggests that archetypal symbolism can be a new resource of aesthetic experience design.

  • SVM-based posture identification with a single waist-located triaxial accelerometer

     Rodriguez Martin, Daniel Manuel; Sama Monsonis, Albert; Perez Lopez, Carlos; Català Mallofré, Andreu; Cabestany Moncusi, Joan; Rodríguez Molinero, Alejandro
    Expert systems with applications
    Vol. 40, num. 18, p. 7203-7211
    DOI: 10.1016/j.eswa.2013.07.028
    Date of publication: 2013-12
    Journal article

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    Analysis of human body movement is an important research area, specially for health applications. In order to assess the quality of life of people with mobility problems like Parkinson¿s disease o stroke patients, it is crucial to monitor and assess their daily life activities. The main goal of this work is the characterization of basic activities using a single triaxial accelerometer located at the waist. This paper presents a novel postural detection algorithm based in SVM methods which is able to detect and identify Walking, Stand, Sit, Lying, Sit to Stand, Stand to sit, Bending up/down, Lying from Sit and Sit from Lying transitions with a sensitivity of 97% and specificity of 84% with 2884 postures analyzed from 31 healthy volunteers. Parameters and models found have been tested in another dataset from Parkinson¿s disease patients, achieving results of 98% of sensitivity and 78% of specificity in postural transitions. The proposed algorithm has been optimized to be easily implemented in real-time system for on-line monitoring applications.

    Analysis of human body movement is an important research area, specially for health applications. In order to assess the quality of life of people with mobility problems like Parkinson’s disease o stroke patients, it is crucial to monitor and assess their daily life activities. The main goal of this work is the characterization of basic activities using a single triaxial accelerometer located at the waist. This paper presents a novel postural detection algorithm based in SVM methods which is able to detect and identify Walking, Stand, Sit, Lying, Sit to Stand, Stand to sit, Bending up/down, Lying from Sit and Sit from Lying transitions with a sensitivity of 97% and specificity of 84% with 2884 postures analyzed from 31 healthy volunteers. Parameters and models found have been tested in another dataset from Parkinson’s disease patients, achieving results of 98% of sensitivity and 78% of specificity in postural transitions. The proposed algorithm has been optimized to be easily implemented in real-time system for on-line monitoring applications.

  • Preface

     Moreno Arostegui, Juan Manuel; Cabestany Moncusi, Joan; Rojas Ruiz, Ignacio
    Neural processing letters
    Vol. 37, num. 1, p. 1
    DOI: 10.1007/s11063-012-9273-6
    Date of publication: 2013-02-01
    Journal article

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  • A self-adaptive hardware architecture with fault tolerance capabilities

     Soto, Javier; Moreno Arostegui, Juan Manuel; Cabestany Moncusi, Joan
    Neurocomputing
    Vol. 121, p. 25-31
    DOI: 10.1016/j.neucom.2012.10.038
    Date of publication: 2013-12-09
    Journal article

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    This paper describes a Fault Tolerance System (FTS) implemented in a new self-adaptive hardware architecture. This architecture is based on an array of cells that implements in a distributed way self-adaptive capabilities. The cell includes a configurable multiprocessor, so it can have between one and four processors working in parallel, with a programmable configuration mode that allows selecting the size of program and data memories. The self-elimination and self-replication capabilities of cell(s) are performed when the FTS detects a failure in any of the processors that include it, so that this cell(s) will be self-discarded for future implementations. Other adaptive capabilities of the system are self-routing, self-placement and runtime self-configuration. Additionally, it is described as an example application and a software tool that has been implemented to facilitate the development of applications to test the system.

  • An asynchronous finite-state-machine-based buck-boost converter for on-chip adaptive power supply

     Fernández, Daniel; Madrenas Boadas, Jordi; Alarcon Cot, Eduardo Jose
    Analog integrated circuits and signal processing
    Vol. 74, num. 1, p. 227-238
    DOI: 10.1007/s10470-012-9975-8
    Date of publication: 2013-01
    Journal article

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    In this paper we present an asynchronous finite-state machine digital controller co-integrated with an on-chip non-inverting buck-boost power converter with dynamic signal-tracking capabilities. The mostly-digital controller functionally implements a non-PWM zone-wise control law through asynchronous circuitry, thus exhibiting self-timed minimum latency and ultra low power operation due to gate switching activity. Experimental results on a 0.35 µm CMOS technology demonstrate an efficiency up to 80 % with a switching frequency of 2.86 MHz.

    In this paper we present an asynchronous finite-state machine digital controller co-integrated with an on-chip non-inverting buck-boost power converter with dynamic signal-tracking capabilities. The mostly-digital controller functionally implements a non-PWM zone-wise control law through asynchronous circuitry, thus exhibiting self-timed minimum latency and ultra low power operation due to gate switching activity. Experimental results on a 0.35 lm CMOS technology demonstrate an efficiency up to 80 % with a switching frequency of 2.86 MHz

  • Access to the full text
    A wearable inertial measurement unit for long-term monitoring in the dependency care area  Open access

     Rodriguez Martin, Daniel Manuel; Perez Lopez, Carlos; Sama Monsonis, Albert; Cabestany Moncusi, Joan; Català Mallofré, Andreu
    Sensors
    Vol. 13, num. 10, p. 14079-14104
    DOI: 10.3390/s131014079
    Date of publication: 2013-10-18
    Journal article

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    Human movement analysis is a field of wide interest since it enables the assessment of a large variety of variables related to quality of life. Human movement can be accurately evaluated through Inertial Measurement Units (IMU), which are wearable and comfortable devices with long battery life. The IMU's movement signals might be, on the one hand, stored in a digital support, in which an analysis is performed a posteriori. On the other hand, the signal analysis might take place in the same IMU at the same time as the signal acquisition through online classifiers. The new sensor system presented in this paper is designed for both collecting movement signals and analyzing them in real-time. This system is a flexible platform useful for collecting data via a triaxial accelerometer, a gyroscope and a magnetometer, with the possibility to incorporate other information sources in real-time. A SD card can store all inertial data and a Bluetooth module is able to send information to other external devices and receive data from other sources. The system presented is being used in the real-time detection and analysis of Parkinson's disease symptoms, in gait analysis, and in a fall detection system.

    Human movement analysis is a field of wide interest since it enables the assessment of a large variety of variables related to quality of life. Human movement can be accurately evaluated through Inertial Measurement Units (IMU), which are wearable and comfortable devices with long battery life. The IMU’s movement signals might be, on the one hand, stored in a digital support, in which an analysis is performed a posteriori. On the other hand, the signal analysis might take place in the same IMU at the same time as the signal acquisition through online classifiers. The new sensor system presented in this paper is designed for both collecting movement signals and analyzing them in real-time. This system is a flexible platform useful for collecting data via a triaxial accelerometer, a gyroscope and a magnetometer, with the possibility to incorporate other information sources in real-time. A μSD card can store all inertial data and a Bluetooth module is able to send information to other external devices and receive data from other sources. The system presented is being used in the real-time detection and analysis of Parkinson’s disease symptoms, in gait analysis, and in a fall detection system

  • Advances in computational intelligence

     Rojas, Ignacio; Cabestany Moncusi, Joan; Joya, Gonzalo
    Softcomputing
    Vol. 17, num. 2, p. 195-197
    DOI: DOI 10.1007/s00500-012-0899-0
    Date of publication: 2013-02
    Journal article

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  • A study on output normalization in multiclass SVMs

     González Abril, Luis; Velasco Morente, Francisco; Angulo Bahón, Cecilio; Ortega Ramirez, Juan Antonio
    Pattern recognition letters
    Vol. 34, num. 3, p. 344-348
    DOI: 10.1016/j.patrec.2012.11.003
    Date of publication: 2013-02-01
    Journal article

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    The use of binary support vector machines (SVMs) in multi-classification is addressed in this paper. Margins associated to the bi-classifiers, since they depend on the geometrical disposition of the classes being separated, are, in general, of various magnitudes. In order to overcome this scaling problem, a normalization process should be applied on the SVMs’ outputs. Thus, a new normalization approach is presented based on the convex hulls that contain the classes to be separated. Furthermore, a theoretical study is developed which justifies the proposed approach, and an interpretation is provided. An empirical study is also carried out to compare this normalization with others found in the literature.

  • Supervisory control interface design for unmanned aerial vehicles through GEDIS-UAV

     Lorite, Salvador; Muñoz, Adolfo; Tornero, Josep; Ponsa Asensio, Pedro; Pastor Llorens, Enrique
    DOI: 10.1007/978-3-642-39232-0
    Date of publication: 2013-07-26
    Book chapter

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    This paper reflects the state of art in the field of human factors for unmanned aerial vehicles. It describes the GEDIS-UAV guide, which is a modification of the GEDIS guide. It also shows the evaluation of the Sky-eye project graphical user interface as an example of the methodology. The analysis and evaluation method reflected in this paper may be used to improve the graphical user interface of any unmanned aerial vehicle.

    This paper reflects the state of art in the field of human factors for unmanned aerial vehicles. It describes the GEDIS-UAV guide, which is a mod- ification of the GEDIS guide. It also shows the evaluation of the Sky-eye project graphical user interface as an example of the methodology. The analy- sis and evaluation method reflected in this paper may be used to improve the graphical user interface of any unmanned aerial vehicle.

  • Millor projecte europeu de recerca

     Cabestany Moncusi, Joan; Rovira, Jordi; Rodríguez, Alejandro
    Award or recognition

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  • TRATAMIENTO DEL DOLOR Y LA ANSIEDAD BASADO EN LA INTERACCION DE ROBOTS SOCIALES CON

     Diaz Boladeras, Marta; Angulo Bahón, Cecilio
    Competitive project

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  • CIP-297178-FATE - Fall Detector for the Elder

     Esposito, Gennaro; Cabestany Moncusi, Joan; Cortes Garcia, Claudio Ulises
    Competitive project

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  • Contribució en la modelització de la rugositat superficial obtinguda en els processos de honing utilitzant xarxes neuronals artificials

     Sivatte Adroer, Maurici
    Universitat Politècnica de Catalunya
    Theses

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    A partir de dades experimentals obtingudes en una màquina d'assaigs construïda a l'efecte,l'objectiu d'aquesta tesi és modelitzar el procés de brunyit dels interiors de cilindres d'acer(procés de honing), utilitzant les xarxes neuronals artificials.Es seleccionen les cinc variables de procés que es consideren més rellevants i es defineix elPerceptró Multicapa amb l'algoritme d'aprenentatge backpropagation i el sistema de validaciócross-validation, com a xarxa neuronal base.En una primera fase es dissenya un model neuronal, de forma què a partir de les dades de procésseleccionades, dóna el paràmetre de rugositat superficial "Ra" que hi correspondria.En una segona fase es modelitza el problema invers. A partir del valor de la rugositat superficial"Ra" que es desitja, el model neuronal explicita els valors de les variables de procés que lafarien possible.Finalment, es dissenya un model iteratiu, utilitzant les xarxes seleccionades en les fasesanteriors, per millorar la modelització inversa.

  • On the Automatic Detection of Otolith Features for Fish Species Identification and their Age Estimation  Open access

     Soria Perez, Jose Antonio
    Department of Electronic Engineering, Universitat Politècnica de Catalunya
    Theses

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    L'eix principal d'aquesta tesi tracta sobre la detecció automàtica d'irregularitats en senyals, tant si s'extreuen de les imatges fotogràfiques com si es capturen de sensors electrònics, així com la seva possible aplicació en la detecció d'estructures morfològiques en otòlits de peixos per identificar espècie, i realitzar una estimació de l'edat en el moment de la seva mort. Des de la vesant més biològica, els otòlits, que son estructures calcàries que es troben en el sistema auditiu de tots els peixos teleostis, constitueixen un dels elements principals en l'estudi i la gestió de l'ecologia marina. En aquest sentit, l'ús combinat de descriptors de Fourier i l'anàlisi de components és el primer pas i la clau per caracteritzar la seva morfologia i identificar espècies marines. No obstant, una de les limitacions principals d'aquest sistema de representació consisteix en la interpretació limitada de les irregularitats que pot desenvolupar, així com l'ús que es realitza dels coeficients en tasques de classificació, els quals, acostumen a seleccionar-se manualment tant pel que respecta a la quantitat com la seva importància. La detecció automàtica d'irregularitats en senyals, així com la seva interpretació, es va tractar per primera vegada sota el marc del 'Best-Basis paradigm'. En aquest sentit, l'algorisme Local Discriminant Bases (LDB) de N. Saito es basa en la Transformada Wavelet Discreta (DWT) per descriure el posicionament de característiques dintre de l'espai temporal-freqüencial, i en una mesura discriminant basada en l'energia per guiar la cerca automàtica de característiques dintre d'aquest domini. Propostes més recents basades en funcions de densitat han tratat de superar les limitacions de les mesures d'energia amb un èxit relatiu. No obstant, encara s'han de desenvolupar noves estratègies que siguin més consistents amb la capacitat real de classificació i ofereixin més generalització al reduir la dimensió de les dades d'entrada. La proposta d'aquest treball es centra en un nou marc per senyals unidimensionals. Una de les conclusions principals que s'extreu és que aquesta generalització passa per establir un marc de mesures acotades on els valors reflecteixen la densitat on cap classe es solapa. Això condiciona bastant la selecció de característiques i el tamany del vector necessari per identificar les classes correctament, que s'han d'establir no nomès en base a valors discriminants globals si no també en informació complementària sobre la disposició de les mostres en el domini. Les noves eines s'han utilitzat en diferents estudis d'espècie de lluç, on s'han obtingut bons resultats d'identificació. No obstant, l'aportació principal consisteix en la interpretació que s'extreu de les característiques seleccionades, i que inclou l'estructura d'irregularitats, la posició temporal-freqüencial, extensió i rellevància, que es ressalta sobre la mateixa imatge o senyal. En quan a la determinació de l'edat, s'ha plantejat una nova estratègia de demodulació de senyals per compensar l'efecte del creixement no lineal en els perfils d'intensitat. Tot i que inicialment aquesta tècnica és capaç d'adaptar-se automàticament al creixement individual de cada peix, els resultats amb el LDB suggereixen estudiar l'efecte de les condicions lumíniques sobre els otòlits amb la finalitat de trobar tècniques més fiables per reduir la variació del contrast. Mentrestant s'ha plantejat una nova teoria per realitzar estimacions d'edat en peixos en base als otòlits. Aquesta teoria suggereix que si la corba de creixment és coneguda, el període regular dels anells en el perfil d'intensitat demodulat està relacionat amb la longitud total del radi d'on s'agafa el perfil original. Per tant, si la periodicitat es pot mesurar, es possible conèixer l'edat exacta del peix sense usar extractors de característiques o classificadors, la qual cosa tindria implicacions importants en l'ús de recursos computacionals i en les tècniques actuals d'estimació de l'edat.

    This thesis deals with the automatic detection of features in signals, either extracted from photographs or captured by means of electronic sensors, and its possible application in the detection of morphological structures in fish otoliths so as to identify species and estimate their age at death. From a more biological perspective, otoliths, which are calcified structures located in the auditory system of all teleostean fish, constitute one of the main elements employed in the study and management of marine ecology. In this sense, the application of Fourier descriptors to otolith images, combined with component analysis, is habitually a first and a key step towards characterizing their morphology and identifying fish species. However, some of the main limitations arise from the poor interpretation that can be obtained with this representation and the use that is made of the coefficients, as generally they are selected manually for classification purposes, both in quantity and representativity. The automatic detection of irregularities in signals, and their interpretation, was first addressed in the so-called Best-Basis paradigm. In this sense, Saito's Local discriminant Bases algorithm (LDB) uses the Discrete Wavelet Packet Transform (DWPT) as the main descriptive tool for positioning the irregularities in the time-frequency space, and an energy-based discriminant measure to guide the automatic search of relevant features in this domain. Current density-based proposals have tried to overcome the limitations of the energy-based functions with relatively little success. However, other measure strategies more consistent with the true classification capability, and which can provide generalization while reducing the dimensionality of features, are yet to be developed. The proposal of this work focuses on a new framework for one-dimensional signals. An important conclusion extracted therein is that such generalization involves a mesure system of bounded values representing the density where no class overlaps. This determines severely the selection of features and the vector size that is needed for proper class identification, which must be implemented not only based on global discriminant values but also on the complementary information regarding the provision of samples in the domain. The new tools have been used in the biological study of different hake species, yielding good classification results. However, a major contribution lies on the further interpretation of features the tool performs, including the structure of irregularities, time-frequency position, extension support and degree of importance, which is highlighted automatically on the same images or signals. As for aging applications, a new demodulation strategy for compensating the nonlinear growth effect on the intensity profile has been developed. Although the method is, in principle, able to adapt automatically to the specific growth of individual specimens, preliminary results with LDB-based techniques suggest to study the effect of lighting conditions on the otoliths in order to design more reliable techniques for reducing image contrast variation. In the meantime, a new theoretic framework for otolith-based fish age estimation has been presented. This theory suggests that if the true fish growth curve is known, the regular periodicity of age structures in the demodulated profile is related to the radial length the original intensity profile is extracted from. Therefore, if this periodicity can be measured, it is possible to infer the exact fish age omitting feature extractors and classifiers. This could have important implications in the use of computational resources anc current aging approaches.

    El eje principal de esta tesis trata sobre la detección automática de singularidades en señales, tanto si se extraen de imágenes fotográ cas como si se capturan de sensores electrónicos, así como su posible aplicación en la detección de estructuras morfológicas en otolitos de peces para identi car especies, y realizar una estimación de la edad en el momento de su muerte. Desde una vertiente más biológica, los otolitos, que son estructuras calcáreas alojadas en el sistema auditivo de todos los peces teleósteos, constituyen uno de los elementos principales en el estudio y la gestión de la ecología marina. En este sentido, el uso combinado de descriptores de Fourier y el análisis de componentes es el primer paso y la clave para caracterizar su morfología e identi car especies marinas. Sin embargo, una de las limitaciones principales de este sistema de representación subyace en la interpretación limitada que se puede obtener de las irregularidades, así como el uso que se hace de los coe cientes en tareas de clasi cación que, por lo general, acostumbra a seleccionarse manualmente tanto por lo que respecta a la cantidad y a su importancia. La detección automática de irregularidades en señales, y su interpretación, se abordó por primera bajo el marco del Best-Basis paradigm. En este sentido, el algoritmo Local Discriminant Bases (LDB) de N. Saito utiliza la Transformada Wavelet Discreta (DWT) para describir el posicionamiento de características en el espacio tiempo-frecuencia, y una medida discriminante basada en la energía para guiar la búsqueda automática de características en dicho dominio. Propuestas recientes basadas en funciones de densidad han tratado de superar las limitaciones que presentaban las medidas de energía con un éxito relativo. No obstante, todavía están por desarrollar nuevas estrategias más consistentes con la capacidad real de clasi cación y que ofrezcan mayor generalización al reducir la dimensión de los datos de entrada. La propuesta de este trabajo se centra en un nuevo marco para señales unidimensionales. Una conclusión principal que se extrae es que dicha generalización pasa por un marco de medidas de valores acotados que re ejen la densidad donde las clases no se solapan. Esto condiciona severamente el proceso de selección de características y el tamaño del vector necesario para identi car las clases correctamente, que se ha de establecer no sólo en base a valores discriminantes globales sino también en la información complementaria sobre la disposición de las muestras en el dominio. Las nuevas herramientas han sido utilizadas en el estudio biológico de diferentes especies de merluza, donde se han conseguido buenos resultados de identi cación. No obstante, la contribución principal subyace en la interpretación que dicha herramienta hace de las características seleccionadas, y que incluye la estructura de las irregularidades, su posición temporal-frecuencial, extensión en el eje y grado de relevancia, el cual, se resalta automáticamente sobre la misma imagen o señal. Por lo que respecta a la determinación de la edad, se ha planteado una nueva estrategia de demodulación para compensar el efecto del crecimiento no lineal en los per les de intensidad. Inicialmente, aunque el método implementa un proceso de optimización capaz de adaptarse al crecimiento individual de cada pez automáticamente, resultados preliminares obtenidos con técnicas basadas en el LDB sugieren estudiar el efecto de las condiciones lumínicas sobre los otolitos con el n de diseñar algoritmos que reduzcan la variación del contraste de la imagen más ablemente. Mientras tanto, se ha planteado una nueva teoría para estimar la edad de los peces en base a otolitos. Esta teoría sugiere que si la curva de crecimiento real del pez se conoce, el período regular de los anillos en el per l demodulado está relacionado con la longitud total del radio donde se extrae el per l original. Por tanto, si dicha periodicidad es medible, es posible determinar la edad exacta sin necesidad de utilizar extractores de características o clasi cadores, lo cual tendría implicaciones importantes en el uso de recursos computacionales y en las técnicas actuales de estimación de la edad.

    L'eix principal d'aquesta tesi tracta sobre la detecció automàtica d'irregularitats en senyals, tant si s'extreuen de les imatges fotogrà ques com si es capturen de sensors electrònics, així com la seva possible aplicació en la detecció d'estructures morfològiques en otòlits de peixos per identi car espècies, i realitzar una estimació de l'edat en el moment de la seva mort. Des de la vesant més biològica, els otòlits, que son estructures calcàries que es troben en el sistema auditiu de tots els peixos teleostis, constitueixen un dels elements principals en l'estudi i la gestió de l'ecologia marina. En aquest sentit, l'ús combinat de descriptors de Fourier i l'anàlisi de components es el primer pas i la clau per caracteritzar la seva morfologia i identi car espècies marines. No obstant, una de les limitacions principals d'aquest sistema de representació consisteix en la interpretació limitada de les irregularitats que pot desenvolupar, així com l'ús que es realitza dels coe cients en tasques de classi cació, els quals, acostumen a ser seleccionats manualment tant pel que respecta a la quantitat com la seva importància. La detecció automàtica d'irregularitats en senyals, així com la seva interpretació, es va tractar per primera vegada sota el marc del Best-Basis paradigm. En aquest sentit, l'algorisme Local Discriminant Bases (LDB) de N. Saito es basa en la Transformada Wavelet Discreta (DWT) per descriure el posicionament de característiques dintre de l'espai temporal-freqüencial, i en una mesura discriminant basada en l'energia per guiar la cerca automàtica de característiques dintre d'aquest domini. Propostes més recents basades en funcions de densitat han tractat de superar les limitacions de les mesures d'energia amb un èxit relatiu. No obstant, encara s'han de desenvolupar noves estratègies que siguin més consistents amb la capacitat real de classi cació i ofereixin més generalització al reduir la dimensió de les dades d'entrada. La proposta d'aquest treball es centra en un nou marc per senyals unidimensionals. Una de las conclusions principals que s'extreu es que aquesta generalització passa per establir un marc de mesures acotades on els valors re ecteixin la densitat on cap classe es solapa. Això condiciona bastant el procés de selecció de característiques i la mida del vector necessari per identi car les classes correctament, que s'han d'establir no només en base a valors discriminants globals si no també en informació complementària sobre la disposició de les mostres en el domini. Les noves eines s'han utilitzat en diferents estudis d'espècies de lluç, on s'han obtingut bons resultats d'identi cació. No obstant, l'aportació principal consisteix en la interpretació que l'eina extreu de les característiques seleccionades, i que inclou l'estructura de les irregularitats, la seva posició temporal-freqüencial, extensió en l'eix i grau de rellevància, el qual, es ressalta automàticament sobre les mateixa imatge o senyal. En quan a l'àmbit de determinació de l'edat, s'ha plantejat una nova estratègia de demodulació de senyals per compensar l'efecte del creixement no lineal en els per ls d'intensitat. Tot i que inicialment aquesta tècnica desenvolupa un procés d'optimització capaç d'adaptar-se automàticament al creixement individual de cada peix, els resultats amb el LDB suggereixen estudiar l'efecte de les condicions lumíniques sobre els otòlits amb la nalitat de dissenyar algorismes que redueixin la variació del contrast de les imatges més ablement. Mentrestant s'ha plantejat una nova teoria per realitzar estimacions d'edat en peixos en base als otòlits. Aquesta teoria suggereix que si la corba de creixement és coneguda, el període regular dels anells en el per l d'intensitat demodulat està relacionat amb la longitud total de radi d'on s'agafa el per l original. Per tant, si la periodicitat es pot mesurar, es possible conèixer l'edat exacta del peix sense usar extractors de característiques o classi cadors, la qual cosa tindria implicacions importants en l'ús de recursos computacionals i en les tècniques actuals d'estimació de l'edat.

  • METHODS OF COVERT COMMUNICATION OF SPEECH SIGNALS BASED ON A BIO-INSPIRED PRINCIPLE  Open access

     Ballesteros Larrotta, Dora Maria
    Department of Electronic Engineering, Universitat Politècnica de Catalunya
    Theses

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    Esta tesis presenta dos métodos de comunicación encubierta de señales de voz utilizando un concepto bio-inspirado, conocido como la habilidad de adaptación de señales de voz. Si se tienen dos señales de voz con diferente texto, la primera un mensaje secreto y la segunda una señal de voz con contenido no confidencial (señal objetivo), es posible que el mensaje secreto se manipule para suene como la señal objetivo. La habilidad de adaptación de las señales de voz se utiliza para encriptar señales de voz en el dominio wavelet. A diferencia de los esquemas tradicionales, la señal de voz encriptada es una señal con texto legible y el proceso de permutación se basa en la adaptación entre los coeficientes wavelet del mensaje secreto y los coeficientes wavelet de la señal de voz objetivo. Entonces, el sistema puede ser visto como un caso especial de encriptación tiempo-frecuencia (TFS). Este es un sistema perfectamente secreto porque la longitud de la clave es igual a la longitud del mensaje secreto, hay tantos mensajes secretos como señales encriptadas y el mapeo entre las entradas y las salidas es uno a uno. Se concluye que el sistema supera el ataque de fuerza bruta. Adicionalmente, el mensaje secreto puede ser recuperado por el usuario autorizado aún si la señal de voz encriptada es manipulada utilizando ataques de compresión, filtrado o re-muestreo.En el caso de esteganografía, se proponen dos esquemas. El primero se denomina enmascaramiento wavelet eficiente (EWM) y el segundo EWM mejorado (iEWM). Los dos aprovechan la propiedad de enmascaramiento del sistema auditivo humano (HAS) utilizando un proceso eficiente de enmascaramiento basado en la adaptación del mensaje secreto a la señal de voz huésped. EWM utiliza una sustitución directa basada en el parámetro Pd el cual relaciona la amplitud de los coeficientes wavelet de la señal huésped con los coeficientes wavelet del mensaje secreto adaptado. Los 5 bits menos significativos (LSBs) de los coeficientes wavelet de la señal huésped se reemplazan con el valor de Pd. A diferencia de EWM, iEWM utiliza sustitución directa. En este caso, los coeficientes wavelet del mensaje secreto adaptado se ocultan directamente en los coeficientes wavelet de la señal huésped. El número de bits varía de acuerdo a la amplitud de los coeficientes wavelet de la señal huésped, a mayor amplitud mayor es el número de LSBs que son modificados. No obstante, los bits más significativos (MSBs) se mantienen intactos de acuerdo al parámetro de control SBH. Mientras EWM demostró ser más transparente (es decir que la señal estego no genera sospechas sobre la existencia del mensaje secreto), iEWM es más robusto frente a manipulaciones de señal como compresión y re-muestreo.Dado que los dos modelos propuestos necesitan conocer de antemano tanto el mensaje secreto como la señal objetivo (o la señal huésped), no se pueden utilizar en aplicaciones de tiempo real. De tal forma, se presenta un esquema de esteganografía que trabaja sobre dispositivos hardware en el cual la señal estego se obtiene casi inmediatamente como se pronuncia el mensaje secreto.

    This work presents two speech hiding methods based on a bio-inspired concept known as the ability of adaptation of speech signals. A cryptographic model uses the adaptation to transform a secret message to a non-sensitive target speech signal, and then, the scrambled speech signal is an intelligible signal. The residual intelligibility is extremely low and it is appropriate to transmit secure speech signals. On the other hand, in a steganographic model, the adapted speech signal is hidden into a host signal by using indirect substitution or direct substitution. In the first case, the scheme is known as Efficient Wavelet Masking (EWM), and in the second case, it is known as improved-EWM (iEWM). While EWM demonstrated to be highly statistical transparent, the second one, iEWM, demonstrated to be highly robust against signal manipulations. Finally, with the purpose to transmit secure speech signals in real-time operation, a hardware-based scheme is proposed

    Esta tesis presenta dos métodos de comunicación encubierta de señales de voz utilizando un concepto bio-inspirado, conocido como la “habilidad de adaptación de señales de voz”. El modelo de criptografía utiliza la adaptación para transformar un mensaje secreto a una señal de voz no confidencial, obteniendo una señal de voz encriptada legible. Este método es apropiado para transmitir señales de voz seguras porque en la señal encriptada no quedan rastros del mensaje secreto original. En el caso de esteganografía, la señal de voz adaptada se oculta en una señal de voz huésped, utilizando sustitución directa o indirecta. En el primer caso el esquema se denomina EWM y en el segundo caso iEWM. EWM demostró ser altamente transparente, mientras que iEWM demostró ser altamente robusto contra manipulaciones de señal. Finalmente, con el propósito de transmitir señales de voz seguras en tiempo real, se propone un esquema para dispositivos hardware.

  • What groups of factors do senior executives believe affect their use of executive information systems?  Open access

     Cano Giner, Josep Lluis
    Department of Business Administration, Universitat Politècnica de Catalunya
    Theses

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    En un entorno altamente competitivo y turbulento, los ejecutivos necesitan formas más eficientes para analizar sus empresas, los mercados y la competencia. El objetivo es ayudarles para que sus organizaciones sean más competitivas y, en consecuencia, logren sobrevivir a los cambios que se están produciendo a su alrededor. Los sistemas de información ejecutivos (EIS) pueden ayudar a los directivos a acceder a aquellos datos internos y externos que necesitan para poder tomar las decisiones más adecuadas y alcanzar los objetivos de sus organizaciones. Necesitamos saber cuáles son los factores que, en opinión de los directivos sénior, afectan el uso de los sistemas de información ejecutivos, pues estos, como cualquier otro tipo de software, se han diseñado para ser utilizados directamente por sus destinatarios finales, en este caso, los directivos sénior.El objetivo de esta tesis es descubrir qué factores consideran los directivos sénior que les afectan en su uso de los EIS; comparar los factores que ellos proponen con los que se mencionan en otros estudios a fin de determinar su importancia, y agrupar los factores que afectan o que pueden afectar a los directivos sénior. La metodología que se propone para agrupar todos estos factores es el mapeo de conceptos (concept mapping).La presente tesis se estructura en cinco secciones, además de la introducción y la discusión sobre sus motivaciones: el marco conceptual, la metodología de investigación, el análisis y las conclusiones, la reflexión y la discusión, las referencias y los anexos. Dentro del marco conceptual, en la sección I se define a los directivos sénior, los EIS y el Modelo de Aceptación de Tecnología.La primera pregunta de investigación era ¿Es necesario realizar más investigaciones cualitativas para obtener información más valiosa sobre dichos factores? Puedo confirmar que es necesario realizar más investigación cualitativa para recabar información más valiosa sobre los factores (presentados en la sección 5.I). Obtuvimos 15 factores de las entrevistas iniciales y 79 factores de la revisión de la literatura. Sin embargo, los directivos sénior puntuaron más los 15 factores iniciales obtenidos de las entrevistas que los demás factores.La segunda pregunta de investigación era: ¿Qué grupos de factores consideran los directivos sénior que afectan el uso que hacen de los sistemas de información ejecutivos? Analizando los resultados del estudio realizado con MDS y análisis de clústeres, en la sección 5.II presentamos doce grupos de factores.La tercera pregunta de investigación era: ¿Qué importancia tienen estos factores para los directivos sénior? Detallamos la lista de clústeres, ordenados en función de su importancia media, así como la puntuación media obtenida.La principal contribución científica de esta tesis es haber completado una pequeña parte de la investigación sobre una de las teorías de TI más testeadas y estudiadas: la TAM. Esta tesis demuestra la importancia de la investigación cualitativa para estudiar un tipo específico de TI y un tipo específico de usuario antes de llevar a cabo una investigación cuantitativa.La principal contribución metodológica es que no es nada fácil realizar una investigación con directivos ejecutivos, si bien, como se pone de manifiesto en esta tesis, la metodología del mapeo de conceptos puede ayudar a facilitar el proceso. En esta tesis, se detallan otras contribuciones científicas y metodológicas.En mi opinión, mi modesta aportación consiste en proporcionar a los directivos sénior proyectos de EIS que entiendan su realidad y sus necesidades más y mejor, así como ofrecer a los investigadores nuevas oportunidades de investigación -en concreto , animo a otros investigadores a estudiar la importancia de los estudios cualitativos previos, aplicados a otros tipos de usuarios y sistemas. Otra posibilidad de investigación es utilizar mapas conceptuales para desarrollar proyectos de implementación y comparar el éxito de dichos proyectos.

    In a highly competitive and turbulent environment, executives need more efficient ways to analyze their companies, markets and competitors. The aim is to help their organizations become more competitive and, as a result, survive the changes taking place around them. Executive Information Systems (EIS) can help executives access the internal and external data they need to be able to make the right decisions and achieve their organizations' objectives. We need to know the factors what senior executives believe affect their use of executive information systems because EIS, like any other software, are designed to be used directly by users, in this case, senior executives. The objective of this thesis is to uncover which factors senior executives feel affect their use of EIS, compare the factors they propose to those mentioned in other studies to determine their importance, and group the factors which affect or may affect senior executives. The methodology proposed to group these factors together is Concept Mapping. The structure of this thesis is divided into five main sections after the introduction and the discussion on motivations: the conceptual framework, research methodology, analysis and findings, reflection and discussion, references, and annexes. In the conceptual framework section I define senior executives, EIS and Technology Acceptance Model. The first research question was: Is additional qualitative research needed to find more valuable information about the factors? I can confirm that more qualitative research is necessary to uncover more valuable information about the factors (as presented in section 5.i. above). I extracted 15 factors from the initial interviews and 79 factors from the literature review. However, senior executives rated the 15 initial factors taken from interviews higher than the rest of factors. The second research question was: What groups of factors do senior executives believe affect their use of executive information systems? Examining the results of the survey with MDS and cluster analysis, I have presented twelve groups of factors in section 5.ii. The third research question was: How important are these groups of factors for senior executives? I detail the list of clusters ordered by their average ranking in terms of importance and the average score received. The main scientific contribution of this thesis is having completed one small part of research on one of the most tested and studied theories in IT: TAM. This thesis demonstrates the importance that qualitative research has in terms of studying one type of IT and one type of user before carrying out quantitative research. The main methodological contribution is that it is not easy to do research with senior executives, but, as this thesis shows, the Concept Mapping methodology can help facilitate this process. There are other scientific and methodological contributions detailed in the thesis. This is, I believe, my modest contribution to offering senior executives EIS projects which understand them and their needs more and better while also providing researchers new opportunities for research and I would encourage other researchers to study the importance of previous qualitative studies applied to other kinds of users and systems. Another opportunity for research is to use concept maps to develop implementation projects and compare the success of those projects with other projects which didn't use the concept map as a tool to define the project itself

  • Experience the world with archetypal symbols: a new form of esthetics.

     Chang, Huang-ming; Ivonin, Leonid; Diaz Boladeras, Marta; Català Mallofré, Andreu; Chen, Wei; Rauterberg, Mattias
    Lecture notes in computer science
    Vol. 8028, p. 205-214
    DOI: 10.1007/978-3-642-39351-8
    Date of publication: 2013-03-01
    Journal article

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    According to the theories of symbolic interactionism, phenomenology of perception and archetypes, we argue that symbols play the key role in translating the information from the physical world to the human experience, and archetypes are the universal knowledge of cognition that generates the background of human experience (the life-world). Therefore, we propose a conceptual framework that depicts how people experience the world with symbols, and how archetypes relate the deepest level of human experience. This framework indicates a new direction of research on memory and emotion, and also suggests that archetypal symbolism can be a new resource of aesthetic experience desig

    According to the theories of symbolic interactionism, phenomenology of perception and archetypes, we argue that symbols play the key role in translating the information from the physical world to the human experience, and archetypes are the universal knowledge of cognition that generates the background of human experience (the life-world). Therefore, we propose a conceptual framework that depicts how people experience the world with symbols, and how archetypes relate the deepest level of human experience. This framework indicates a new direction of research on memory and emotion, and also suggests that archetypal symbolism can be a new resource of aesthetic experience design.

  • Access to the full text
    Energy efficient smartphone-based activity recognition using fixed-point arithmetic  Open access

     Anguita, Davide; Ghio, Alessandro; Oneto, Luca; Llanas Parra, Francesc Xavier; Reyes Ortiz, Jorge Luis
    Journal of universal computer science
    Vol. 19, num. 9, p. 1295-1314
    Date of publication: 2013
    Journal article

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    In this paper we propose a novel energy efficient approach for the recognition of human activities using smartphones as wearable sensing devices, targeting assisted living applications such as remote patient activity monitoring for the disabled and the elderly. The method exploits fixed-point arithmetic to propose a modified multiclass Support Vector Machine (SVM) learning algorithm, allowing to better preserve the smartphone battery lifetime with respect to the conventional floating-point based formulation while maintaining comparable system accuracy levels. Experiments show comparative results between this approach and the traditional SVM in terms of recognition performance and battery consumption, highlighting the advantages of the proposed method.

    In this paper we propose a novel energy efficient approach for the recognition of human activities using smartphones as wearable sensing devices, targeting assisted living applications such as remote patient activity monitoring for the disabled and the elderly. The method exploits fixed-point arithmetic to propose a modified multiclass Support Vector Machine (SVM) learning algorithm, allowing to better pre- serve the smartphone battery lifetime with respect to the conventional floating-point based formulation while maintaining comparable system accuracy levels. Experiments show comparative results between this approach and the traditional SVM in terms of recognition performance and battery consumption, highlighting the advantages of the proposed method.

  • Gait identification by means of box approximation geometry of reconstructed attractors in latent space

     Sama Monsonis, Albert; Ruiz Vegas, Francisco Javier; Agell Jané, Núria; Perez Lopez, Carlos; Català Mallofré, Andreu; Cabestany Moncusi, Joan
    Neurocomputing
    Vol. 121, num. 9, p. 79-88
    DOI: 10.1016/j.neucom.2012.12.042
    Date of publication: 2013-02
    Journal article

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    This paper presents a novel gait recognition method which uses the signals measured by a single inertial sensor located on the waist. This method considers human gait as a dynamical system and employs a few singular values obtained by means of Singular Spectrum Analysis applied to scalar measurements from the inertial sensor. Singular values can be interpreted as the approximate edge length of the bounding box wrapping the attractor in the latent space. Effects of different parameters on the gait recognition performance using patterns from 20 different subjects are analysed.

  • Position and orientation tracking in a ubiquitous monitoring system for Parkinson disease patients with freezing of gait symptom

     Takac, Boris; Català Mallofré, Andreu; Rodriguez Martin, Daniel Manuel; Van Der Aa, Nico; Chen, Wei; Rauterberg, Mattias
    JMIR mobile and ubiquitous health (mhealth & uhealth)
    Vol. 15, num. 7
    DOI: 10.2196/mhealth.2539
    Date of publication: 2013-07
    Journal article

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    Background: Freezing of gait (FoG) is one of the most disturbing and least understood symptoms in Parkinson disease (PD). Although the majority of existing assistive systems assume accurate detections of FoG episodes, the detection itself is still an open problem. The specificity of FoG is its dependency on the context of a patient, such as the current location or activity. Knowing the patient's context might improve FoG detection. One of the main technical challenges that needs to be solved in order to start using contextual information for FoG detection is accurate estimation of the patient's position and orientation toward key elements of his or her indoor environment. Objective: The objectives of this paper are to (1) present the concept of the monitoring system, based on wearable and ambient sensors, which is designed to detect FoG using the spatial context of the user, (2) establish a set of requirements for the application of position and orientation tracking in FoG detection, (3) evaluate the accuracy of the position estimation for the tracking system, and (4) evaluate two different methods for human orientation estimation. Methods: We developed a prototype system to localize humans and track their orientation, as an important prerequisite for a context-based FoG monitoring system. To setup the system for experiments with real PD patients, the accuracy of the position and orientation tracking was assessed under laboratory conditions in 12 participants. To collect the data, the participants were asked to wear a smartphone, with and without known orientation around the waist, while walking over a predefined path in the marked area captured by two Kinect cameras with non-overlapping fields of view. Results: We used the root mean square error (RMSE) as the main performance measure. The vision based position tracking algorithm achieved RMSE = 0.16 m in position estimation for upright standing people. ..

    Background: Freezing of gait (FoG) is one of the most disturbing and least understood symptoms in Parkinson disease (PD). Although the majority of existing assistive systems assume accurate detections of FoG episodes, the detection itself is still an open problem. The specificity of FoG is its dependency on the context of a patient, such as the current location or activity. Knowing the patient's context might improve FoG detection. One of the main technical challenges that needs to be solved in order to start using contextual information for FoG detection is accurate estimation of the patient's position and orientation toward key elements of his or her indoor environment. Objective: The objectives of this paper are to (1) present the concept of the monitoring system, based on wearable and ambient sensors, which is designed to detect FoG using the spatial context of the user, (2) establish a set of requirements for the application of position and orientation tracking in FoG detection, (3) evaluate the accuracy of the position estimation for the tracking system, and (4) evaluate two different methods for human orientation estimation. Methods: We developed a prototype system to localize humans and track their orientation, as an important prerequisite for a context-based FoG monitoring system. To setup the system for experiments with real PD patients, the accuracy of the position and orientation tracking was assessed under laboratory conditions in 12 participants. To collect the data, the participants were asked to wear a smartphone, with and without known orientation around the waist, while walking over a predefined path in the marked area captured by two Kinect cameras with non-overlapping fields of view. Results: We used the root mean square error (RMSE) as the main performance measure. The vision based position tracking algorithm achieved RMSE = 0.16 m in position estimation for upright standing people. ..

  • Wavelet-denoising on hardware devices with Perfect Reconstruction, low latency and adaptive thresholding

     Ballesteros Larrotta, Dora Maria; Moreno Arostegui, Juan Manuel
    Computers and electrical engineering
    Vol. 39, num. 4, p. 1300-1311
    DOI: 10.1016/j.compeleceng.2013.03.005
    Date of publication: 2013-05
    Journal article

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    This paper introduces a wavelet denoising architecture with adaptive thresholding for real-time 1D-systems and without the use of external memories for storing input data or wavelet coefficients. The Discrete Wavelet Transform (DWT) is executed sample-by-sample by a polyphase scheme of the biorthogonal base 5/3. Since the weights of the filters are represented by integer terms and the quantization error is quasi-zero, the principle of Perfect Reconstruction is satisfied. The adaptive threshold is based on a real-time sorting process which calculates the median of the detail coefficients. Simulations are presented to measure the delay, latency, quantization error and hardware cost. A comparison with related works is also provided in order to show the strengths of the current proposal. The good trade-off among reconstruction error, latency, delay and hardware cost permits to use the proposed architecture in a wide variety of signals that require good fidelity and prompt response.