CETpD-UPC -Tech. Research Cen.for Dependency Care and Autonom Liviving
Total activity: 1268
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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1 to 50 of 1268 results
  • Proposal and development of a highly modular and scalable self-adaptive hardware architecture with parallel processing capability

     Soto Vargas, Javier Evandro
    Defense's date: 2014-07-02
    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.

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

     Sanchez Rivera, Giovanny
    Defense's date: 2014-06-12
    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
    Defense's date: 2014-05-21
    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.

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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
    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.

  • 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
    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.

  • 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
    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.

  • Continuous Generalized Procrustes analysis

     Igual, Laura; Perez Sala, Xavier; Escalera, Sergio; Angulo Bahón, Cecilio; De La Torre, Fernando
    Pattern recognition
    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.

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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
    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.

  • Realistic model of compact VLSI FitzHugh-Nagumo oscillators

     Cosp Vilella, Jordi; Binczak, Stéphane; Madrenas Boadas, Jordi; Ruiz Fernández, Daniel
    International journal of electronics
    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.

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

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

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  • 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
    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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    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
    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.

  • 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
    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
    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.

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

     Ballesteros Larrotta, Dora Maria
    Defense's date: 2013-07-15
    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.

  • Human movement analysis by means of accelerometers: Aplication to human gait and motor symptoms of Parkinson's Disease  Open access

     Sama Monsonis, Albert
    Defense's date: 2013-10-03
    Universitat Politècnica de Catalunya
    Theses

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    La tesis que este documento recoge es una aportación al análisis del movimiento humano a partir de las señalescapturadas por acelerómetros. Estos sensores permiten convertir la aceleración producida por algunas partes del cuerpoen señales eléctricas susceptibles de un análisis posterior. El progresivo perfeccionamiento y miniaturización de losacelerómetros ha permitido construir sensores poco invasivos que pueden ser usados de forma ambulatoria para registrarlos movimientos realizados en las actividades de la vida diaria del sujeto.La tesis se focaliza en dos ámbitos. El primero, fundamentalmente clínico, se ha centrado en el análisis del movimiento enenfermos de la Enfermedad de Parkinson (EP). El segundo ámbito, más general, ha consistido en relacionar las señalesacelerométricas con características de la marcha. Con este fin, se han desarrollado métodos para la obtención de lavelocidad de la marcha y la longitud del paso, así como para la identificación de personas. En ambos ámbitos se haempleado un único acelerómetro situado en un lado de la cintura.La EP es una enfermedad neurodegenerativa que produce primordialmente trastornos del movimiento en los pacientes quela sufren. Los principales sóntomas motores de la enfermedad son 1) los temblores, 2) la lentitud de movimientos obradicinesia, 3) la congelación de la marcha (freezing of gait FoG) y 4) los movimientos involuntarios o discinesias. Los tresprimeros síntomas aparecen cuando la medicación no ha alcanzado un efecto terapeútico efectivo. Estos periodos seconocen habitualmente como período o estado motor OFF. Los periodos en los cuales la medicación hace efecto y lospacientes presentan una movilidad normal (o casi normal) son los periodos o estados motores ON. Las discinesiasaparecen principalmente cuando el nivel de medicación en sangre es excesivo. Tanto las discinesias como los estadosOFF son consecuencia de un defecto en la administración de la medicación. Un dispositivo no invasivo que detecte yregistre las discinesias y ambos periodos ON y OFF supone una importante herramienta que permite al médico prescribircon mayor precisión la dosis de medicamento adecuada a su paciente.El trabajo realizado en esta tesis en el ámbito de la EP ha consistido en el desarrollo de algoritmos de detección dediscinesias y periodos OFF. Estos algoritmos han sido adaptados para proporcionar una detección en tiempo real, de formaque se han empleado ya en un estudio piloto en los que el ajuste de medicación suministrada por una bomba de infusiónsubcutánea se realiza de forma automática en función de la presencia de discinesias y el estado motor del paciente.La experiencia ganada en el tratamiento de la señal acelerométrica proveniente de enfermos de Parkinson ha permitidocontribuir en el campo del análisis de la marcha y realizar una aportación que relaciona varios parámetros de la misma conla señal que suministra un único acelerómetro situado en la cintura. No solo la EP puede beneficiarse de este estudio, sinotambién otras enfermedades como la Diabetes o algunas enfermedades ortopédicas y traumatológicas puedenaprovecharse de sus resultados.Por útimo, usando algunas de las ténicas de los estudios anteriores, se ha realizado una importante contribución en elámbito de la identificación biométrica de personas. Se ha puesto de manifiesto que la señal proveniente de un únicoacelerómetro situado en la cintura no solo permite obtener algunas de las características de la marcha sino tambiénpermite identificar a la persona a través del patrón de su marcha. La principal contribución teórica de esta tesis ha sido eldesarrollo de técnicas basadas en la reconstrucción de atractores. Se ha evidenciado que un número muy reducido decaracterísticas procedentes del atractor reconstruido a partir de una serie temporal de medidas de aceleración permite laextracción de los parámetros de la marcha y la identificación de personas.

    This thesis presents the original contributions of the author on the field of human movement analysis from signals captured by accelerometers. These sensors are capable of converting acceleration from some body parts into electric signals for further analysis. The progressive refinement and miniaturization of accelerometers has allowed the development of minimally invasive devices that can be used to ambulatory monitor human movements during daily live activities. The study's contributions mainly fall under two heads: first, the analysis of movement in Parkinson's disease (PD); and, second, the relationship between accelerometer signals and characteristics of gait. To this end, new methods for obtaining speed and length of strides and, also, for identifying people have been developed. In all these studies, a single sensor fixed to the patient's waist has been used. PD is a neurodegenerative disease characterized by movement alterations. The main motor symptoms of PD are 1) tremor, 2) bradykinesia or slowness of movements, 3) freezing of gait and 4) dyskinesia or abnormal involuntary movements. The first three symptoms primarily occur when the medication has not yet reached an effective therapeutic effect. These periods are commonly known as OFF periods or OFF motor state. On the other hand, periods when the patient is suitably responding to the medication are known as ON periods or ON motor state. Dyskinesias mainly appear when the medication blood level is excessive. Both dyskinesias and OFF motor states are caused by a defect in the medication administration. In this sense, a wearable device capable of detecting and recording dyskinesias and OFF periods represents an important tool that enables clinics to more accurately prescribe the medication regimen of a patient. The work done in the field of PD consisted in developing algorithms able to detect dyskinesias and both ON and OFF periods. These algorithms have been adapted to provide real-time detection, which enabled their employment in a pilot study. This clinical study has tested, for the first time, the automatic adjustment of medication performed by means of a subcutaneous infusion pump according to the dyskinesias appearance and motor state of PD patients. The experience gained in the treatment of accelerometric signals from PD has led to contribute in the field of gait analysis. First, new methods for obtaining speed and length of strides from a single sensor fixed to the patient's waist have been obtained. Not only the PD can benefit from this study, but other diseases such as diabetes or some orthopedotraumatological diseases can also benefit from its results. Finally, using some of the techniques of the previous studies, another important contribution has been made in the field of biometric person identification. The work presented shows how the signal obtained from a single accelerometer located at the waist not only enables the extraction of some gait characteristics but also permits the identification of a person through its gait pattern. The main theoretical contribution of this thesis has been the development of techniques based on the reconstruction of attractors. It has been shown that the usage of only a small number of features that characterize the reconstructed attractor obtained from a time series of acceleration measurements makes possible the extraction of important parameters of gait and the person identification.

    La tesis que este documento recoge es una aportaci on al an alisis del movimiento humano a partir de las señales capturadas por aceler ometros. Estos sensores permiten convertir la aceleraci on producida por algunas partes del cuerpo en señales el ectricas susceptibles de un an alisis posterior. El progresivo perfeccionamiento y miniaturización de los aceler ometros ha permitido construir sensores poco invasivos y que pueden ser usados de forma ambulatoria para registrar los movimientos realizados en las actividades de la vida diaria del sujeto. La tesis se focaliza en dos ambitos. El primero, fundamentalmente cl inico, se ha centrado en el an alisis del movimiento en enfermos de la Enfermedad de Parkinson (EP). El segundo ambito, m as general, ha consistido en relacionar las señales acelerom etricas con caracter sticas de la marcha. Con este fin, se han desarrollado m etodos para la obtenci on de la velocidad de la marcha y la longitud del paso, as í como para la identificaci on de personas. En ambos ambitos se ha empleado un unico aceler ometro situado en un lado de la cintura. La EP es una enfermedad neurodegenerativa que produce primordialmente trastornos del movimiento en los pacientes que la sufren. Los principales sí ntomas motores de la enfermedad son 1) los temblores, 2) la lentitud de movimientos o bradicinesia, 3) la congelaci on de la marcha (freezing of gait FoG) y 4) los movimientos involuntarios o discinesias. Los tres primeros s ntomas aparecen cuando la medicaci on no ha alcanzado un efecto terape utico efectivo. Estos periodos se conocen habitualmente como per odo o estado motor OFF. Los periodos en los cuales la medicaci on hace efecto y los pacientes presentan una movilidad normal (o casi normal) son los periodos o estados motores ON. Las discinesias aparecen principalmente cuando el nivel de medicaci on en sangre es excesivo. Tanto las discinesias como los estados OFF son consecuencia de un defecto en la administraci on de la medicaci on. Un dispositivo no invasivo que detecte y registre las discinesias y ambos periodos ON y OFF supone una importante herramienta que permite al m edico prescribir con mayor precisi on la dosis de medicamento adecuada a su paciente. El trabajo realizado en esta tesis en el ambito de la EP ha consistido en el desarrollo de algoritmos de detecci on de discinesias y periodos OFF. Estos algoritmos han sido adaptados para proporcionar una detecci on en tiempo real, de forma que se han empleado ya en un estudio piloto en los que el ajuste de medicaci on suministrada por una bomba de infusi on subcut anea se realiza de forma autom atica en funci on de la presencia de discinesias y el estado motor del paciente. La experiencia ganada en el tratamiento de la señal acelerom etrica proveniente de enfermos de Parkinson ha permitido contribuir en el campo del an alisis de la marcha y realizar una aportaci on que relaciona varios par ametros de la misma con la señal que suministra un unico aceler ometro situado en la cintura. No solo la EP puede bene ciarse de este estudio, sino tambi en otras enfermedades como la Diabetes o algunas enfermedades ortop edicas y traumatol ogicas pueden aprovecharse de sus resultados. Por ultimo, usando algunas de las t ecnicas de los estudios anteriores, se ha realizado una importante contribuci on en el ambito de la identi caci on biom etrica de personas. Se ha puesto de mani esto que la señal proveniente de un unico aceler ometro situado en la cintura no solo permite obtener algunas de las caracter sticas de la marcha sino tambi en permite identi car a la persona a trav es del patr on de su marcha. La principal contribuci on te orica de esta tesis ha sido el desarrollo de t ecnicas basadas en la reconstrucci on de atractores. Se ha evidenciado que un n umero muy reducido de caracter sticas procedentes del atractor reconstruido a partir de una serie temporal de medidas de aceleraci on permite la extracci on de los par ametros de la marcha y la identi caci on de personas

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

     Sivatte Adroer, Maurici
    Defense's date: 2013-12-18
    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.

  • Millor projecte europeu de recerca

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

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

     Lorite, Salvador; Muñoz, Adolfo; Tornero, Josep; Ponsa Asensio, Pedro; Pastor Llorens, Enrique
    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.

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

     Cano Giner, Josep Lluis
    Defense's date: 2013-02-18
    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

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

     Soria Perez, Jose Antonio
    Defense's date: 2013-01-21
    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.

  • A self-adaptive hardware architecture with fault tolerance capabilities

     Soto, Javier; Moreno Arostegui, Juan Manuel; Cabestany Moncusi, Joan
    Neurocomputing
    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.

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    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
    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

  • 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
    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.

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    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
    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.

  • 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
    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.

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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
    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.

  • Advances in computational intelligence

     Rojas, Ignacio; Cabestany Moncusi, Joan; Joya, Gonzalo
    Softcomputing
    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
    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.

  • Real-time, speech-in-speech hiding scheme based on least significant bit substitution and adaptive key

     Ballesteros Larrotta, Dora Maria; Moreno Arostegui, Juan Manuel
    Computers and electrical engineering
    Date of publication: 2013-03-05
    Journal article

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    Real-time, embedded speech-in-speech hiding has not been widely researched. Nevertheless, it could be useful, among other cases, in secure mobile telephony. In this paper, we propose a new scheme of data hiding which takes advantage of the masking property of the Human Auditory System (HAS) to hide a secret (speech) signal into a host (speech) signal. The embedding process is carried out into the wavelet coefficients of the speech signals. The main point of the proposed scheme is that the embedding process is suitable for real-time processing, and the secret¿s coefficients are relocated by an adaptive key, instead of a pseudo-noise sequence of some approaches. The latency of the embedding module makes this approach useful for real-time speech communication because the total delay added by the proposed system is low compared to the highest delay allowed for a high quality speech transmission

    Real-time, embedded speech-in-speech hiding has not been widely researched. Nevertheless, it could be useful, among other cases, in secure mobile telephony. In this paper, we propose a new scheme of data hiding which takes advantage of the masking property of the Human Auditory System (HAS) to hide a secret (speech) signal into a host (speech) signal. The embedding process is carried out into the wavelet coefficients of the speech signals. The main point of the proposed scheme is that the embedding process is suitable for real-time processing, and the secret’s coefficients are relocated by an adaptive key, instead of a pseudo-noise sequence of some approaches. The latency of the embedding module makes this approach useful for real-time speech communication because the total delay added by the proposed system is low compared to the highest delay allowed for a high quality speech transmission.

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    A bit more on the ability of adaptation of speech signals  Open access

     Ballesteros Larrotta, Dora Maria; Moreno Arostegui, Juan Manuel
    Revista Facultad de Ingeniería. Universidad de Antioquía
    Date of publication: 2013-03
    Journal article

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    Some traditional digital signal processing techniques encompass enhancement, filtering, coding, compression, detection and recognition. Recently, it has been presented a new hypothesis of signal processing known as the ability of adaptation of speech signals: an original speech signal may sound similar to a target speech signal if a relocation process of its wavelet coefficients is applied. This hypothesis is true under some conditions theoretically defined. In this paper we present the basic idea behind the hypothesis of adaptation and moreover, we test the hypothesis within four cases: speech signals with the same gender and language, speech signals with the same gender but different language, speech signals with the same language but different gender, and speech signals with different gender and language. It is found that the hypothesis is true if the requirements are satisfied, even if the gender or the language of the original and target signals are not the same.

    Some traditional digital signal processing techniques encompass enhancement, filtering, coding, compression, detection and recognition. Recently, it has been presented a new hypothesis of signal processing known as the ability of adaptation of speech signals: an original speech signal may sound similar to a target speech signal if a relocation process of its wavelet coefficients is applied. This hypothesis is true under some conditions theoretically defined. In this paper we present the basic idea behind the hypothesis of adaptation and moreover, we test the hypothesis within four cases: speech signals with the same gender and language, speech signals with the same gender but different language, speech signals with the same language but different gender, and speech signals with different gender and language. It is found that the hypothesis is true if the requirements are satis® ed, even if the gender or the language of the original and target signals are not the same.

  • 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
    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.

  • 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)
    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
    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.

  • 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
    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

  • Preface

     Moreno Arostegui, Juan Manuel; Cabestany Moncusi, Joan; Rojas Ruiz, Ignacio
    Neural processing letters
    Date of publication: 2013-02-01
    Journal article

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  • European Network for FALL prevention, intervention & security E-NO FALLS

     Català Mallofré, Andreu
    Participation in a competitive project

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

     Diaz Boladeras, Marta; Angulo Bahón, Cecilio
    Participation in a competitive project

     Share

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

     Esposito, Gennaro; Cabestany Moncusi, Joan; Cortes Garcia, Claudio Ulises
    Participation in a competitive project

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

     Cosp Vilella, Jordi; Martínez García, Herminio
    European Conference on Circuit Theory and Design
    Presentation's date: 2013-09-10
    Presentation of work at congresses

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    Continuous-time filters (CTFs) with automatic tuning loops are nonlinear feedback systems with potential instability. Thus, their appropriate linear dynamic modeling should be obtained to assure stability in case of an improved design of the loop controllers is to be carried out. A systematic approach using a small signal model would allow obtaining these controllers. However, bifurcations and nonlinear phenomena may appear which cannot be predicted by this analysis. This leads to potential instability, semiperiodic or chaotic behavior and, thus, circuit malfunction. The aim of this paper is to show by means of simulations and experimental results that nonlinear phenomena, which cannot be predicted by the common small signal analysis, may appear in this kind of circuits when circuit parameters are varied.

    Continuous–time filters (CTFs) with automatic tuning loops are nonlinear feedback systems with potential instability. Thus, their appropriate linear dynamic modeling should be obtained to assure stability in case of an improved design of the loop controllers is to be carried out. A systematic approach using a small signal model would allow obtaining these controllers. However, bifurcations and nonlinear phenomena may appear which cannot be predicted by this analysis. This leads to potential instability, semiperiodic or chaotic behavior and, thus, circuit malfunction. The aim of this paper is to show by means of simulations and experimental results that nonlinear phenomena, which cannot be predicted by the common small signal analysis, may appear in this kind of circuits when circuit parameters are varied.

  • Access to the full text
    Design of an on-chip linear-assisted DC-DC voltage regulator  Open access

     Cosp Vilella, Jordi; Martínez García, Herminio
    IEEE International Conference on Electronics, Circuits and Systems
    Presentation's date: 2013-12-10
    Presentation of work at congresses

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    This article shows the design of an on-chip CMOS linear-assisted DC-DC regulator. It results a good alternative topology to classic switching DC-DC power converters. In the presented technique, an auxiliary linear regulator is used to cancel the output voltage ripple and provides fast responses for load and line variations. On the other hand, a switching converter, connected in parallel, allows supplying almost the whole output current demanded by the load. The objective of this linear-assisted regulator or hybrid topology is to achieve a high efficiency of switching converters, with suitable load and line regulation features, typical of linear regulators. In this kind of on-chip applications, CMOS is the current prevailing technology. Thus, in order to implement on-chip power supply systems and on-chip power management systems with low-to-medium current consumption, this structure has good features.

    This article shows the design of an on-chip CMOS linear-assisted DC-DC regulator. It results a good alternative topology to classic switching DC-DC power converters. In the presented technique, an auxiliary linear regulator is used to cancel the output voltage ripple and provides fast responses for load and line variations. On the other hand, a switching converter, connected in parallel, allows supplying almost the whole output current demanded by the load. The objective of this linear-assisted regulator or hybrid topology is to achieve a high efficiency of switching converters, with suitable load and line regulation features, typical of linear regulators. In this kind of on-chip applications, CMOS is the current prevailing technology. Thus, in order to implement on-chip power supply systems and on-chip power management systems with low-to-medium current consumption, this structure has good features.

    Postprint (author’s final draft)

  • Comparative and adaptation of step detection and step length estimators to a lateral belt worn accelerometer

     Sayeed, Taufique; Sama Monsonis, Albert; Català Mallofré, Andreu; Cabestany Moncusi, Joan
    IEEE International Conference on e-Health Networking, Applications and Services
    Presentation's date: 2013-10-10
    Presentation of work at congresses

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    Parkinson¿s Disease (PD) is a neurodegenerative disease that predominantly alter patients¿ motor performance and compromises the speed, the automaticity and fluidity of natural movements. The patients fluctuate between periods in which they can move almost normally for some hours (ON state) and periods with motor disorders (OFF state). Gait properties are affected by the motor state of a patient: reduced stride length, reduced gait speed, increased stride width etc. The ability to assess the motor states (ON/OFF) on a continuous basis for long time without disturbing the patients¿ daily life activities is an important component of PD management. An accurate report of motor states could allow clinics to adjust the medication regimen to avoid OFF periods. The real-time monitoring will also allow an online treatment by combining, for instance, with automatic drug-administration pump doses. Many studies have attempted to extract gait properties through a belt-worn single tri-axial accelerometer. In this paper, a user friendly position is proposed to place the accelerometer and three step detection methods and three step length estimators are compared considering the proposed sensor placement in signals obtained from healthy volunteers and PD patients. Adaptation methods to these step length estimators are also proposed and compared. The comparison shows that the adapted estimators improve the performance with the new proposed step detection method and reduce errors in respect of the original methods.

    Parkinson’s Disease (PD) is a neurodegenerative disease that predominantly alter patients’ motor performance and compromises the speed, the automaticity and fluidity of natural movements. The patients fluctuate between periods in which they can move almost normally for some hours (ON state) and periods with motor disorders (OFF state). Gait properties are affected by the motor state of a patient: reduced stride length, reduced gait speed, increased stride width etc. The ability to assess the motor states (ON/OFF) on a continuous basis for long time without disturbing the patients’ daily life activities is an important component of PD management. An accurate report of motor states could allow clinics to adjust the medication regimen to avoid OFF periods. The real-time monitoring will also allow an online treatment by combining, for instance, with automatic drug-administration pump doses. Many studies have attempted to extract gait properties through a belt-worn single tri-axial accelerometer. In this paper, a user friendly position is proposed to place the accelerometer and three step detection methods and three step length estimators are compared considering the proposed sensor placement in signals obtained from healthy volunteers and PD patients. Adaptation methods to these step length estimators are also proposed and compared. The comparison shows that the adapted estimators improve the performance with the new proposed step detection method and reduce errors in respect of the original methods.

  • Human activity and motion disorder recognition: towards smarter interactive cognitive environments

     Reyes Ortiz, Jorge Luis; Ghio, Alessandro; Anguita, Davide; Parra Perez, Xavier; Cabestany Moncusi, Joan; Català Mallofré, Andreu
    European Symposium on Artificial Neural Networks, Computational Intelligence and Machine Learning
    Presentation's date: 2013-04-24
    Presentation of work at congresses

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    The rise of ubiquitous computing systems in our environment is engendering a strong need for novel approaches of human-computer interaction. Either for extending the existing range of possibilities and services available to people or for providing assistance the ones with limited conditions. Human Activity Recognition (HAR) is playing a central role in this task by offering the input for the development of more interactive and cognitive environments. This has motivated the organization of the ESANN 2013 Special Session in Human Activity and Motion Disorder Recognition and the execution of a competition in HAR. Here, a compilation of the most recent proposals in the area are exposed accompanied by the results of the contest calling for innovative approaches to recognize activities of daily living (ADL) from a recently published data set.

    The rise of ubiquitous computing systems in our environment is engendering a strong need for novel approaches of human-computer interaction. Either for extending the existing range of possibilities and services available to people or for providing assistance the ones with limited conditions. Human Activity Recognition (HAR) is playing a central role in this task by offering the input for the development of more interactive and cognitive environments. This has motivated the organization of the ESANN 2013 Special Session in Human Activity and Motion Disorder Recognition and the execution of a competition in HAR. Here, a compilation of the most recent proposals in the area are exposed accompanied by the results of the contest calling for innovative approaches to recognize activities of daily living (ADL) from a recently published data set.

  • Multi-criteria preference disaggregation analysis for classification: an application to model colour preferences

     Ghaderi, Mohammad; Agell Jané, Núria; Ruiz Vegas, Francisco Javier; Sanchez Soler, Monica
    International Conference on Multiple Criteria Decision Making
    Presentation's date: 2013-06-20
    Presentation of work at congresses

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    Classication or discrimination problems consider the assignment of a set of alternatives into predened groups. In some situations, groups are dened in an ordinal way from the most to the least preferred. In the multi-criteria decision-aid (MCDA) literature, this is known as a `sorting' or `learning preferences' problem. Capturing the decision makers (DMs) tacit knowledge, by providing them a training sample to be sorted in an ordinal way, is considered of interest in the knowledge management eld. Extracting and mathematically framing the preference system of the decision maker (expert) enables us to predict preferences for cases that are outside of the training sample. Much eort has been made in this direction in the area of articial intelligence, specically in fuzzy set theory and machine learning systems. Preference disaggregation, as one of the most popular approaches for capturing the preference system of DMs, in MCDA is used to infer global preference models from given preferential patterns. Among others, we can highlight: UTA (UTilites Additives); UTASTAR; UTADIS (UTilites Additives Discriminates) ; ELECTRE TRI ; and MHDIS methods. The aim of these approaches is to provide a model that is as consistent as possible with the decisions made by the DM. This research includes a literature review of the existing methodologies for learning preferences and a comparison between some of them. An application related to colour preferences is used to compare these methodologies. Finally, managerial applications involving learning colour preferences are studied.

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    Usability of vision-based interfaces  Open access

     Manresa-Yee, Cristina; Amengual, Esperança; Ponsa Asensio, Pedro
    Congreso Internacional de Interacción Persona-Ordenador
    Presentation's date: 2013-09-17
    Presentation of work at congresses

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    Vision-based interfaces can employ gestures to interact with an interactive system without touching it. Gestures are frequently modelled in laboratories, and usability testing should be carried out. However, often these interfaces present usability issues, and the great diversity of uses of these interfaces and the applications where they are used, makes it difficult to decide which factors to take into account in a usability test. In this paper, we review the literature to compile and analyze the usability factors and metrics used for vision-based interfaces.

    Vision-based interfaces can employ gestures to interact with an interactive system without touching it. Gestures are frequently modelled in laboratories, and usability testing should be carried out. However, often these interfaces present usability issues, and the great diversity of uses of these interfaces and the applications where they are used, makes it difficult to decide which factors to take into account in a usability test. In this paper, we review the literature to compile and analyze the usability factors and metrics used for vision-based interfaces.

  • Access to the full text
    A first approximation in order to define a Difficulty Factor of the bi-classification in a dataset by using SVMs  Open access

     Gonzalez Abril, Luis; Angulo Bahón, Cecilio
    Jornadas de ARCA
    Presentation's date: 2013-06-25
    Presentation of work at congresses

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    The main aim in this paper is to analyze the complexity of a Support Vector Machine -SVM- in the construction of a classifier for a bi-classification problem on a specific dataset. Hence, an index is defined in terms of both, the Lagrange multipliers and the number of support vectors. Experimentation for cheching the defined index is carried out with a well.known dataset, the Glass Identification Database.

    The main aim in this paper is to analyze the complexity of a Support Vector Machine -SVM- in the construction of a classifier for a bi-classification problem on a specific dataset. Hence, an index is defined in terms of both, the Lagrange multipliers and the number of support vectors. Experimentation for cheching the defined index is carried out with a well.known dataset, the Glass Identification Database.

  • Access to the full text
    Group decision-making system based on a qualitative location function: an application to chocolates design  Open access

     Agell Jané, Núria; Sánchez Hernández, Germán; Sanchez Soler, Monica; Ruiz Vegas, Francisco Javier
    International Workshop on Qualitative Reasoning
    Presentation's date: 2013-08-27
    Presentation of work at congresses

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    When a group of experts is involved in the design of a new product as a team, consensus and Group decision making (GDM) techniques able to deal with complex descriptions are required. In addition, individual decisions based on human sensory perception, such as color, smell or taste, are usually qualitative and made under uncertainty. In this paper we consider a methodology based upon qualitative reasoning techniques for representing and synthesizing the information given by a group of experts in order to capture the sensorial aspects of the alternatives. A real application of the proposed GDM method to chocolates design has been conducted throughout 2012 with the Chocolate Chef Oriol Balaguer¿s team. We present the results obtained by applying the proposed methodology to aggregate experts¿ opinion during a creative session. In this session, some members of Oriol Balaguer¿s team tested and evaluated combinations of black chocolate with six different fruits, considered as alternatives, to select the best combination for the design and creation of a new cake.

    When a group of experts is involved in the design of a new product as a team, consensus and Group decision making (GDM) techniques able to deal with complex descriptions are required. In addition, individual decisions based on human sensory perception, such as color, smell or taste, are usually qualitative and made under uncertainty. In this paper we consider a methodology based upon qualitative reasoning techniques for representing and synthesizing the information given by a group of experts in order to capture the sensorial aspects of the alternatives. A real application of the proposed GDM method to chocolates design has been conducted throughout 2012 with the Chocolate Chef Oriol Balaguer’s team. We present the results obtained by applying the proposed methodology to aggregate experts’ opinion during a creative session. In this session, some members of Oriol Balaguer’s team tested and evaluated combinations of black chocolate with six different fruits, considered as alternatives, to select the best combination for the design and creation of a new cake.

  • Selecting the best taste: a group decision-making application to chocolates design

     Agell Jané, Núria; Sánchez Hernández, Germán; Sanchez Soler, Monica; Ruiz Vegas, Francisco Javier
    International Fuzzy Systems Association World Congress and European Society of Fuzzy Logic and Technology Conference
    Presentation's date: 2013-06-27
    Presentation of work at congresses

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    Creation and design of products based on human sensory perceptions, such as color, smell or taste, require the participation of professionals or experts with highly developed sensory abilities. When a group of experts is involved in such creative process as a team, consensus and group decision-making (GDM) techniques able to deal with qualitative descriptions and uncertainty, can be required. In this paper we consider a methodology based upon qualitative reasoning techniques for representing and synthesizing the information given by a group of experts in order to capture the sensorial aspects of the alternatives. A real application of the proposed GDM method to chocolates design has been conducted throughout 2012 with the Chocolate Chef Oriol Balaguer¿s team. We present the results obtained by applying the proposed methodology to aggregate experts¿ opinion during a creative session. In this session, some members of Oriol Balaguer¿s team tested and evaluated combinations of black chocolate with six different fruits, considered as alternatives, to select the best combination for the design and creation of a new cake.

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    A Cloud robotics architecture to foster individual child partnership in medical facilities  Open access

     Navarro, Joan; Sancho-Asensio, Andreu; Garriga, Carles; Albo Canals, Jordi; Ortiz-Villajos Maroto, Julio; Raya Giner, Cristobal; Angulo Bahón, Cecilio; Miralles, David
    IROS Workshop on Cloud Robotics
    Presentation's date: 2013-11-03
    Presentation of work at congresses

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    Robots and automation systems have become a valuable partner in several facets of human life: from learning and teaching, to daily working, including health monitoring and assistance. So far, these appealing robot-based applications are restricted to conduct repetitive, yet useful, tasks due to the reduced individual robots¿ capabilities in terms of processing and computation. This concern prevents current robots from facing more complex applications related to understanding hu- man beings and perceiving their subtle feelings. Such hardware limitations have been already found in the computer science field. In this domain, they are currently being addressed using a new resource exploitation model coined as cloud computing, which is targeted at enabling massive storage and computation using smartly connected and inexpensive commodity hardware. The purpose of this paper is to propose a cloud-based robotics architecture to effectively develop complex tasks related to hospitalized children assistance. More specifically, this paper presents a multi-agent learning system that combines machine learning and cloud computing using low-cost robots to (1) collect and perceive children status, (2) build a human-readable set of rules related to the child-robot relationship, and (3) improve the children experience during their stay in the hos- pital. Conducted preliminary experiments proof the feasibility of this proposal and encourage practitioners to work towards this direction.

    Robots and automation systems have become a valuable partner in several facets of human life: from learning and teaching, to daily working, including health monitoring and assistance. So far, these appealing robot-based applications are restricted to conduct repetitive, yet useful, tasks due to the reduced individual robots’ capabilities in terms of processing and computation. This concern prevents current robots from facing more complex applications related to understanding hu- man beings and perceiving their subtle feelings. Such hardware limitations have been already found in the computer science field. In this domain, they are currently being addressed using a new resource exploitation model coined as cloud computing, which is targeted at enabling massive storage and computation using smartly connected and inexpensive commodity hardware. The purpose of this paper is to propose a cloud-based robotics architecture to effectively develop complex tasks related to hospitalized children assistance. More specifically, this paper presents a multi-agent learning system that combines machine learning and cloud computing using low-cost robots to (1) collect and perceive children status, (2) build a human-readable set of rules related to the child-robot relationship, and (3) improve the children experience during their stay in the hos- pital. Conducted preliminary experiments proof the feasibility of this proposal and encourage practitioners to work towards this direction.

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    Aspectos innovadores del grado de ingeniería de diseño y desarrollo del producto en el campus de la Universidad Politécnica de Cataluña en Vilanova i la Geltrú  Open access

     Vilà Martí, Frederic; Ponsa Asensio, Pedro; Pérez Soriano, Jaume; Roman Jimenez, Jose Antonio
    Congreso Universitario de Innovación Educativa en las Enseñanzas Técnicas
    Presentation's date: 2013-07-10
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    Al finalizar este curso académico la Escuela Politécnica Superior de Ingeniería de Vilanova i la Geltrú tendrá su primer grupo de egresados del grado de ingeniería de diseño y desarrollo del producto. Este artículo presenta de forma reflexiva una primera valoración de las metodologías de enseñanza y aprendizaje que se han llevado a cabo. Así mismo, se exponen los aspectos innovadores con los que se ha querido aportar una diferenciación y singularidad respecto a otros centros que imparten la misma titulación. El enfoque sistemático que aquí se presenta se enlaza con la misión y valores del plan estratégico de nuestro centro en el que se profundiza en aspectos de innovación docente y emprendedurismo.

    Al finalizar este curso académico la Escuela Politécnica Superior de Ingeniería de Vilanova i la Geltrú tendrá su primer grupo de egresados del grado de ingeniería de diseño y desarrollo del producto. Este artículo presenta de forma reflexiva una primera valoración de las metodologías de enseñanza y aprendizaje que se han llevado a cabo. Así mismo, se exponen los aspectos innovadores con los que se ha querido aportar una diferenciación y singularidad respecto a otros centros que imparten la misma titulación. El enfoque sistemático que aquí se presenta se enlaza con la misión y valores del plan estratégico de nuestro centro en el que se profundiza en aspectos de innovación docente y emprendedurismo.