GCEM - Electromagnetic Compatibility Group
Total activity: 668
Type
Research group
Type of group
TECNIO Network / CIT UPC
Acronym
GCEM
Address
Jordi Girona, 1-3. Edifici C4 Campus Nord Open in new window
City
Barcelona
URL
http://www.upc.edu/web/gcem Open in new window
Keywords
GCEM - Grup de Compatibilitat Electromagnètica

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1 to 50 of 668 results
  • Temperature gradient sensor from pulsed power supply duty cycle in ultra-low-power energy harvesting system

     Jove Casulleras, Roger; Ramos Castro, Juan Jose; Corimanya, H; Camps Carmona, Adriano Jose; Alarcon Cot, Eduardo Jose; Amezaga Sarries, Adria; Bou Balust, Elisenda
    Electronics Letters
    Date of publication: 2014-05-22
    Journal article

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    Directly interfacing sensors that link sensors to micro-controllers without a signal conditioning circuit or an analogue-to-digital converter on the one side and energy harvesting systems on the other side are two key enabling technologies to create self-powered autonomous low-cost and low-maintenance sensor networks. In this reported work, both technologies are concurrently combined in such a way that the duty cycle of the pulsed power supply provided by the harvesting system itself yields in turn a temperature gradient sensor functionality. Originally conceived to power a low-power satellite beacon in a CubeSat project, it has found application, among other applications, in automatic air conditioning and heating systems aiming smart buildings.

  • Healthy Life style and Drowsiness Prevention-HEALING DROP

     Fernandez Chimeno, Mireya
    Participation in a competitive project

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  • Red de Investigación Cardiovascular

     Bragos Bardia, Ramon; Riu Costa, Pere Joan; Rosell Ferrer, Francisco Javier
    Participation in a competitive project

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  • In vivo electrical bioimpedance characterization of human lung tissue during the bronchoscopy procedure. A feasibility study

     Sánchez Terrones, Benjamín; Vandersteen, Gerd; Martín Robles, Irene; Castillo Villegas, Diego; Torrego Fernández, Alfons; Riu Costa, Pere Joan; Schoukens, Johan; Bragos Bardia, Ramon
    Medical engineering and physics
    Date of publication: 2013-07
    Journal article

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    Lung biopsies form the basis for the diagnosis of lung cancer. However, in a significant number of cases bronchoscopic lung biopsies fail to provide useful information, especially in diffuse lung disease, so more aggressive procedures are required. Success could be improved using a guided electronic biopsy based on multisine electrical impedance spectroscopy (EIS), a technique which is evaluated in this paper. The theoretical basis of the measurement method and the instrument developed are described, characterized and calibrated while the performance of the instrument is assessed by experiments to evaluate the noise and nonlinear source of errors from measurements on phantoms. Additional preliminary results are included to demonstrate that it is both feasible and safe to monitor in vivo human lung tissue electrical bioimpedance (EBI) during the bronchoscopy procedure. The time required for performing bronchoscopy is not extended because the bioimpedance measurements, present no complications, tolerance problems or side effects among any of the patients measured.

    Lung biopsies form the basis for the diagnosis of lung cancer. However, in a significant number of cases bronchoscopic lung biopsies fail to provide useful information, especially in diffuse lung disease, so more aggressive procedures are required. Success could be improved using a guided electronic biopsy based on multisine electrical impedance spectroscopy (EIS), a technique which is evaluated in this paper. The theoretical basis of the measurement method and the instrument developed are described, characterized and calibrated while the performance of the instrument is assessed by experiments to evaluate the noise and nonlinear source of errors from measurements on phantoms. Additional preliminary results are included to demonstrate that it is both feasible and safe to monitor in vivo human lung tissue electrical bioimpedance (EBI) during the bronchoscopy procedure. The time required for performing bronchoscopy is not extended because the bioimpedance measurements, present no complications, tolerance problems or side effects among any of the patients measured.

  • Analysis of pre-processing techniques when using validation methods in computational electromagnetic simulations

     Jauregui Telleria, Ricardo; Ventosa Llopart, Josep Oriol; Silva Martinez, Fernando; Kunze, Marco
    IET science measurement and technology
    Date of publication: 2013-05
    Journal article

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    In computational electromagnetic simulations, most validation methods have been developed to quantify the similarity of two datasets, making them an objective tool for test engineers to discuss data on a similar basis. However, these methods do not always agree with the expert's opinion. The main problem when a validation method is used, is not taking into account the 'preprocessing' required by the expert to analyse a particular characteristic in the comparison. In this study, two different preprocessing techniques are used to show the influence they have on the results of the validation methods in relation to the opinion of the expert. The Institution of Engineering and Technology 2013.

  • An application of fractional differintegration to heart rate variability time series

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose; Capdevila, Lluis; Parrado, Eva
    Computer methods and programs in biomedicine
    Date of publication: 2013-07
    Journal article

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    Fractional differintegration is used as a new tool to characterize heart rate variability time series. This paper proposes and focuses in two indexes (ac and fnQ) derived from the fractional differintegration operator. Both indexes are applied to fractional Gaussian noise (fGn) and actual RR time series in order to test their behavior. In the analysis of monofractal time series, ac is linearly related with the Hurst exponent and the estimation of the exponent by the proposed index has lower variance than by using Detrended Fluctuation Analysis (DFA) or the periodogram. The other index fnQ quantifies how the time series adjust to a monofractal time series. Age, postural changes and paced breathing cause significant changes on fnQ while ac only shows significant changes due to posture. In the analyzed actual HRV time series, ac shows good correlation with the short term scaling exponent obtained by DFA, LF/HF and RMSSD while no correlations have been found for fnQ.

  • The help4mood wearable sensor network for inconspicuous activity measurement

     Pérez Diaz de Cerio, David; Ruiz Boque, Silvia; Rosell Ferrer, Francisco Javier; Ramos Castro, Juan Jose; Valenzuela Gonzalez, Jose Luis; Colomé Castellví, Josep Maria
    IEEE Wireless communications
    Date of publication: 2013-08
    Journal article

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    The Help4Mood EU FP7 project (H4M) [1] proposes to significantly advance the state-ofthe-art in computerized support for people with Major Depression by monitoring mood, physical activity and voice characteristics while promoting activities in reaction to examined inputs. Employing actigraphy can provide supplementary data about patients with depression. Nonetheless, its use is not standardized and there is a lack of public analyses about treated patients with depression using this technique, which is the objective of the project. The purpose of the Personal Monitoring System (PMS) used in H4M is to compile objective data about the changes and trends of activity patterns during long periods of time. This would comprise daily activity, rest time and, if possible, sleep quality. The PMS uses inconspicuous methods but keeping the cost associated with sensor installation at the patient¿s home to a minimum. This work focuses on the Wireless Sensor Network (WSN) enhancements introduced after real testbeds and considering User Quality of Experience (QoE), mainly oriented to reduce energy consumption and required data transmission and consequently improving the autonomy and range of the sensors.

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    Design of the magnetic diagnostics unit onboard LISA pathfinder  Open access

     Mateos, Ignacio; Diaz Aguiló, Marc; Ramos Castro, Juan Jose; Lobo, J.A.; Garcia-berro Montilla, Enrique
    Aerospace science and technology
    Date of publication: 2013-04
    Journal article

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    LISA (Laser Interferometer Space Antenna) is a joint mission of ESA and NASA which aims to be the first space-borne gravitational wave observatory. Due to the high complexity and technological challenges that LISA will face, ESA decided to launch a technological demonstrator, LISA Pathfinder. The payload of LISA Pathfinder is the so-called LISA Technology Package, and will be the highest sensitivity geodesic explorer flown to date. The LISA Technology Package is designed to measure relative accelerations between two test masses in nominal free fall (geodesic motion). The magnetic, thermal and radiation disturbances affecting the payload are monitored and dealt by the diagnostics subsystem. The diagnostics subsystem consists of several modules, and one of these is the magnetic diagnostics unit. Its main function is the assessment of differential acceleration noise between test masses due to the magnetic effects. To do so, it has to determine the magnetic characteristics of the test masses, namely their magnetic remanences and susceptibilities. In this paper we show how this can be achieved to the desired accuracy. (c) 2012 Elsevier Masson SAS. All rights reserved.

    LISA (Laser Interferometer Space Antenna) is a joint mission of ESA and NASA which aims to be the first space-borne gravitational wave observatory. Due to the high complexity and technological challenges that LISA will face, ESA decided to launch a technological demonstrator, LISA Pathfinder. The payload of LISA Pathfinder is the so-called LISA Technology Package, and will be the highest sensitivity geodesic explorer flown to date. The LISA Technology Package is designed to measure relative accelerations between two test masses in nominal free fall (geodesic motion). The magnetic, thermal and radiation disturbances affecting the payload are monitored and dealt by the diagnostics subsystem. The diagnostics subsystem consists of several modules, and one of these is the magnetic diagnostics unit. Its main function is the assessment of differential acceleration noise between test masses due to the magnetic effects. To do so, it has to determine the magnetic characteristics of the test masses, namely their magnetic remanences and susceptibilities. In this paper we show how this can be achieved to the desired accuracy.

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    A comparison of heartbeat detectors for the seismocardiogram  Open access

     Garcia Gonzalez, Miquel Angel; Argelagós Palou, Ariadna; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    Computing in Cardiology
    Presentation's date: 2013-09-24
    Presentation of work at congresses

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    The study aimed to study the accuracy in RR time series derived from the seismocardiogram when employing different heartbeat detectors in subjects measured in a quiet environment. The ECG and seismocardiogram of 17 healthy volunteers was recorded at a sampling frequency of 5 kHz using a Biopac acquisition system. The seismocardiogram was acquired using a triaxial accelerometer (LIS344ALH, ST Microelectronics). Four detectors of the heartbeat from the seismocardiogram were employed relying either on the Continuous Wavelet Transform or bandpass filtering. The detectors adapt their parameters to the morphology of the signal by estimating mean heart rate and the bandwidth of the signal associated to the heartbeat. For all detectors, the standard deviation of the error in the obtained RR time series is in mean slightly higher than 2 ms and the percentage of obtained RR time intervals that have an error higher than 30 ms is around 3.5%. The seismocardiogram, when measured in a quiet environment, can be used instead of the ECG to obtain reliable RR time series when using proper heartbeat detectors.

    The study aimed to study the accuracy in RR time series derived from the seismocardiogram when employing different heartbeat detectors in subjects measured in a quiet environment. The ECG and seismocardiogram of 17 healthy volunteers was recorded at a sampling frequency of 5 kHz using a Biopac acquisition system. The seismocardiogram was acquired using a triaxial accelerometer (LIS344ALH, ST Microelectronics). Four detectors of the heartbeat from the seismocardiogram were employed relying either on the Continuous Wavelet Transform or bandpass filtering. The detectors adapt their parameters to the morphology of the signal by estimating mean heart rate and the bandwidth of the signal associated to the heartbeat. For all detectors, the standard deviation of the error in the obtained RR time series is in mean slightly higher than 2 ms and the percentage of obtained RR time intervals that have an error higher than 30 ms is around 3.5%. The seismocardiogram, when measured in a quiet environment, can be used instead of the ECG to obtain reliable RR time series when using proper heartbeat detectors.

  • UPCSAT-1, demostrador CubeSat para observación terrestre

     Jove Casulleras, Roger; Camps Carmona, Adriano Jose; Vall-llossera Ferran, Mercedes Magdalena; Bou Balust, Elisenda; Ramos Castro, Juan Jose; Alarcon Cot, Eduardo Jose; Alonso Arroyo, Alberto
    Congreso de la Asociación Española de Teledetección
    Presentation's date: 2013-10
    Presentation of work at congresses

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    UPCSat-1, es el primer proyecto de la Universitat Politécnica de Catalunya para construir y lanzar un pico- satélite. El objetivo principal de este proyecto es construir, ensamblar, testear y poner en órbita baja terrestre (LEO) un sensor óptico y un sensor de oxígeno monoatómico entre otros demostradores tecnológicos. Empezado en 2007 y actualmente en fase de integración, el satélite UPCSat-1 pretende demostrar la validez de la plataforma y las tecnologías que incorpora. Su objetivo es adquirir el know-how para la fabricación de CubeSats para preparar misiones más complejas en un futuro cercano. Por otro lado el proyecto tiene un fuerte componente educacional puesto que algunos de los subsistemas han sido desarrollados por nuestros estudiantes a través de sus proyectos finales de carrera. Se espera el lanzamiento para antes de 2015.

  • Differences in QRS locations due to ECG lead: relationship with breathing

     Garcia Gonzalez, Miquel Angel; Argelagós Palou, Ariadna; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    Mediterranean Conference on Medical and Biological Engineering and Computing
    Presentation's date: 2013-09-27
    Presentation of work at congresses

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    Results of heart rate variability analysis depend on the accuracy of the RR time series that is measured only in one lead of the ECG. RR time series can subtly change from lead to lead. We have obtained the ECG of 21 healthy subjects in a quiet measurement, sampled at 5 kHz and from the I and II standard leads. For each subject a total of 60 minutes was measured. The QRS complexes in both leads have been detected using a conventional QRS detector plus a further refinement using a matching template. Differences between the locations of the QRS complexes have been quantified and compared with the breathing signal of each subject as well as the derived RR time series. The typical uncertainty in the fiducial points and RR time series is usually below 1 ms and the errors are modulated by breathing.

    Results of heart rate variability analysis depend on the accuracy of the RR time series that is measured only in one lead of the ECG. RR time series can subtly change from lead to lead. We have obtained the ECG of 21 healthy subjects in a quiet measurement, sampled at 5 kHz and from the I and II standard leads. For each subject a total of 60 minutes was measured. The QRS complexes in both leads have been detected using a conventional QRS detector plus a further refinement using a matching template. Differences between the locations of the QRS complexes have been quantified and compared with the breathing signal of each subject as well as the derived RR time series. The typical uncertainty in the fiducial points and RR time series is usually below 1 ms and the errors are modulated by breathing.

  • Synchrosqueezing index for detecting drowsiness based on the respiratory effort signal

     Rodríguez Ibáñez, Noelia; Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; De Rosario, H.; Ramos Castro, Juan Jose
    Mediterranean Conference on Medical and Biological Engineering and Computing
    Presentation's date: 2013-09-27
    Presentation of work at congresses

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    Objective: The aim of this work is to evaluate a new index to assess the alertness state of drivers based on the respiratory dynamics derived from an inductive band using the variability of the respiratory rhythms assessed by Synchrosqueezing (SSQ). Background: Biomedical variables like abdominal effort, which is related to autonomic nervous system, provides direct information of the driver physiological state, instead of indirect indicia of the participant's behavior. Method: The respiration data used in this study was recorded by doing 18 simulator tests in a controlled scenario. In order to evaluate the viability of variability of the respiratory rhythms assessed by Synchrosqueezing (SSQ) Mean and the Standard Deviation of the Instantaneous Respiration Frequency (MIRF and SDIRF) obtained in the analysis for awake states and drowsy states individually was calculated. Results: The results demonstrate the viability of drowsiness detection in simulator using abdominal effort signal analyzed by Synchrosqueezing based on the significant results of the statistical analysis comparing the Mean (MIRF) and de Standard Deviation (SDIRF) of both awake and drowsy intervals instantaneous respiration frequency (MIRF 0.28 Hz ± SDIRF 0.06 Hz (awake) vs. MIRF 0.21 Hz ± SDIRF 0.06 Hz (drowsy), N=18, p<0.001, t=4.88.

    Objective: The aim of this work is to evaluate a new index to assess the alertness state of drivers based on the respiratory dynamics derived from an inductive band using the variability of the respiratory rhythms assessed by Synchrosqueezing (SSQ). Background: Biomedical variables like abdominal effort, which is related to autonomic nervous system, provides direct information of the driver physiological state, instead of indirect indicia of the participant’s behavior. Method: The respiration data used in this study was recorded by doing 18 simulator tests in a controlled scenario. In order to evaluate the viability of variability of the respiratory rhythms assessed by Synchrosqueezing (SSQ) Mean and the Standard Deviation of the Instantaneous Respiration Frequency (MIRF and SDIRF) obtained in the analysis for awake states and drowsy states individually was calculated. Results: The results demonstrate the viability of drowsiness detection in simulator using abdominal effort signal analyzed by Synchrosqueezing based on the significant results of the statistical analysis comparing the Mean (MIRF) and de Standard Deviation (SDIRF) of both awake and drowsy intervals instantaneous respiration frequency (MIRF 0.28 Hz ± SDIRF 0.06 Hz (awake) vs. MIRF 0.21 Hz ± SDIRF 0.06 Hz (drowsy), N=18, p<0.001, t=4.88.

  • Co-simulation methodology to evaluate digital communication systems interfered by transients

     Pous Sola, Marc; Silva Martinez, Fernando
    International Symposium on Electromagnetic Compatibility
    Presentation's date: 2013-09-04
    Presentation of work at congresses

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    In this paper a method combining different types of simulation is used to evaluate transient interferences over a digital communication system at its frequency band. The method combines different simulation stages; the first one is an electromagnetic simulation, with FDTD numerical method, which is carried out to establish the level of the interference coupled to the digital communication system; at the second stage, the simulation of the transmitted data at the communication system is performed introducing the EM interference calculated at the first stage. The result of this co-simulation will be a BER and other useful indicators to quantify the degradation produced by the transient interference. To show the effectiveness of the co-simulation method first of all the method is validated comparing the results with other evaluation techniques, measuring a real interference over an RFID system. The RFID system is according to the ISO 14443 type B standard, and the interference generated is a burst according to 61000-4-4. Once the co-simulation method is validated, the co-simulation system is used to quantify and decide if an EMC redesign technique of the previous scenario is efficient enough to avoid degradation at the RFID system produced by the burst transient interference.

    In this paper a method combining different types of simulation is used to evaluate transient interferences over a digital communication system at its frequency band. The method combines different simulation stages; the first one is an electromagnetic simulation, with FDTD numerical method, which is carried out to establish the level of the interference coupled to the digital communication system; at the second stage, the simulation of the transmitted data at the communication system is performed introducing the EM interference calculated at the first stage. The result of this co-simulation will be a BER and other useful indicators to quantify the degradation produced by the transient interference. To show the effectiveness of the co-simulation method first of all the method is validated comparing the results with other evaluation techniques, measuring a real interference over an RFID system. The RFID system is according to the ISO 14443 type B standard, and the interference generated is a burst according to 61000-4-4. Once the co-simulation method is validated, the co-simulation system is used to quantify and decide if an EMC redesign technique of the previous scenario is efficient enough to avoid degradation at the RFID system produced by the burst transient interference.

  • Contactless electrical bioimpedance system for monitoring ventilation. A biodevice for vehicle environment

     Macias Macias, Raul; Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Bragos Bardia, Ramon; Fernandez Chimeno, Mireya
    International Conference on Biomedical Electronics and Devices
    Presentation's date: 2013-02
    Presentation of work at congresses

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    Nowadays, automotive companies are focused in improving road traffic safety. For that, not only the vehicle performance is improved but also the driver behavior is monitored. This could be done in many ways. One of them is to monitor a specific physiological parameter using a biodevice. That device should be reliable enough to use in a very noisy environment like a vehicle is. Furthermore, because long-term monitoring is required, any invasive and annoying method should be avoided. Therefore, an electrical bioimpedance device capable of monitoring driver ventilation using several textiles electrodes has been designed and implemented.

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    Ventilation and heart rate monitoring in drivers using a contactless electrical bioimpedance system  Open access

     Macias Macias, Raul; Garcia Cabezas, Maria de la Cruz; Ramos Lara, Rafael Ramon; Bragos Bardia, Ramon; Fernandez Chimeno, Mireya
    International Conference on Electrical Bio-impedance
    Presentation of work at congresses

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    Nowadays, the road safety is one of the most important priorities in the automotive industry. Many times, this safety is jeopardized because of driving under inappropriate states, e.g. drowsiness, drugs and/or alcohol. Therefore several systems for monitoring the behavior of subjects during driving are researched. In this paper, a device based on a contactless electrical bioimpedance system is shown. Using the four-wire technique, this system is capable of obtaining the heart rate and the ventilation of the driver through multiple textile electrodes. These textile electrodes are placed on the car seat and the steering wheel. Moreover, it is also reported several measurements done in a controlled environment, i.e. a test room where there are no artifacts due to the car vibrations or the road state. In the mentioned measurements, the system response can be observed depending on several parameters such as the placement of the electrodes or the number of clothing layers worn by the driver.

    Nowadays, the road safety is one of the most important priorities in the automotive industry. Many times, this safety is jeopardized because of driving under inappropriate states, e.g. drowsiness, drugs and/or alcohol. Therefore several systems for monitoring the behavior of subjects during driving are researched. In this paper, a device based on a contactless electrical bioimpedance system is shown. Using the four-wire technique, this system is capable of obtaining the heart rate and the ventilation of the driver through multiple textile electrodes. These textile electrodes are placed on the car seat and the steering wheel. Moreover, it is also reported several measurements done in a controlled environment, i.e. a test room where there are no artifacts due to the car vibrations or the road state. In the mentioned measurements, the system response can be observed depending on several parameters such as the placement of the electrodes or the number of clothing layers worn by the driver.

  • Low cost EIT system for monitoring the sausage ripening process in food industry

     Bragos Bardia, Ramon; Guasch Petit, Antonio; Sánchez Terrones, Benjamín; Giovinazzo, Giuseppe; Rosell Ferrer, Francisco Javier; Riu Costa, Pere Joan
    International Conference on Electrical Bio-impedance
    Presentation's date: 2013-04-24
    Presentation of work at congresses

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  • The use of regions of interest (ROI) in the estimation of total ventilation in COPD patients by means of EIT

     Riu Costa, Pere Joan; Balleza Ordaz, José Marco; Pérez Alday, Erick Andrés; Vargas Luna, José Miguel
    International Conference on Electrical Bio-impedance
    Presentation's date: 2013-04-25
    Presentation of work at congresses

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  • Drowsiness detection by electrooculogram signal analysis in driving simulator conditions for gold standard signal generation

     Rodríguez-Ibáñez, N.; Meca-Calderón, Pablo; Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Fernandez Chimeno, Mireya
    International Conference on Biomedical Electronics and Devices
    Presentation's date: 2013-02
    Presentation of work at congresses

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    Detection of drowsiness while driving is a leading objective in advanced driver assistance systems. This work presents a new index to assess the alertness state of drivers based on the EOG dynamics derived from a polysomnography device. More than 15 hours of laboratory tests were analyzed in order to detect drowsiness while doing cognitive activities. The proposed method has a sensitivity of 92, 41% and a VPP of 93,41% in detecting drowsiness. The results show that the proposed index may be promising to assess the alertness state of real drivers

  • Textile electrode characterization: Dependencies in the skin-clothing-electrode interface

     Macias Macias, Raul; Fernandez Chimeno, Mireya; Bragos Bardia, Ramon
    International Conference on Electrical Bio-impedance
    Presentation's date: 2013-04
    Presentation of work at congresses

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    Given the advances in the technology known as smart textiles, the use of textile electrodes is more and more common. However this kind of electrodes presents some differences regarding the standard ones as the Ag-AgCl electrodes. Therefore to characterize them as best as possible is required. In order to make the characterization reproducible and repetitive, a skin dummy made of agar-agar and a standardized measurement set-up is used in this article. Thus, some dependencies in the skin-electrode interface are described. These dependencies are related to the surface of the textile electrode, the conductive material and the applied pressure. Furthermore, the dependencies on clothing in the skin-textile electrode interface are also analyzed. Thus, based on some parameters such as textile material, width and number of layers, the behavior of the interface made up by the skin, the textile electrode and clothing is depicted.

    Given the advances in the technology known as smart textiles, the use of textile electrodes is more and more common. However this kind of electrodes presents some differences regarding the standard ones as the Ag-AgCl electrodes. Therefore to characterize them as best as possible is required. In order to make the characterization reproducible and repetitive, a skin dummy made of agar-agar and a standardized measurement set-up is used in this article. Thus, some dependencies in the skin-electrode interface are described. These dependencies are related to the surface of the textile electrode, the conductive material and the applied pressure. Furthermore, the dependencies on clothing in the skin-textile electrode interface are also analyzed. Thus, based on some parameters such as textile material, width and number of layers, the behavior of the interface made up by the skin, the textile electrode and clothing is depicted.

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    Using smartphone bases biodevices for analyzing physiological, psychological and behavioral user¿s habits  Open access

     Guede Fernandez, Federico; Pous Sola, Marc; Garcia Gonzalez, Miquel Angel; Capdevila Ortis, Lluís; Ramos Castro, Juan Jose; Fernandez Chimeno, Mireya
    International Conference on Biomedical Electronics and Devices
    Presentation's date: 2013-02
    Presentation of work at congresses

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    As a consequence of increasing life expectancy, the promotion of lifestyles that allow aging wellbeing guarantees has acquired great importance in the developed countries. However, the adherence to healthy behaviors in young and adult people remains as a big problem in the community health field. The development of markers of adherence to healthy lifestyles and the evaluation its effectiveness is a goal of many research groups. This paper presents a system for analyzing physiological, psychological and behavioural user’s habits using a smartphone and externals biodevices. We use an Android smartphone with an internal tri-axial accelerometer and GPS to monitor physical activity. The smartphone is connected via Bluetooth to a respiratory sensor for breath monitoring. In addition, Android application contains psychological questionnaires to analyze user’s mood state and at the same, social interaction is analyzed tracking phone usage and user’s social network. Finally, the collected information is sent to a remote server for a long-term processing.

  • 2o Concurso de planes de negocio de comercialización de una patente/tecnologia

     Mañanas Villanueva, Miguel Angel; Ramos Castro, Juan Jose
    Award or recognition

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  • Healthy Life style and Drowsiness Prevention-HEALING DROP

     Fernandez Chimeno, Mireya
    Participation in a competitive project

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  • Improved EMC test methods in industrial environments

     Silva Martinez, Fernando
    Participation in a competitive project

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  • Q-00206

     Silva Martinez, Fernando
    Participation in a competitive project

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  • Pla d'Actuació GCEM

     Silva Martinez, Fernando
    Participation in a competitive project

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  • Development of a system to test somnolence detectors with drowsy drivers

     Lopez De la O, Jaime; Rodríguez Ibáñez, Noelia; Nombela, Mario; Barrios, Jose Manuel; Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Fernandez Chimeno, Mireya
    Procedia - Social and behavioral sciences
    Date of publication: 2012
    Journal article

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    Somnolence; Semi-autonomous conduction

  • The Role of uncertainty in the feature selective validation (FSV) method

     Jauregui Telleria, Ricardo; Aragon Homar, Marc; Silva Martinez, Fernando
    IEEE transactions on electromagnetic compatibility
    Date of publication: 2012-11-27
    Journal article

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  • Temperature coefficient improvement for low noise magnetic measurements in LISA

     Mateos, I.; Diaz Aguiló, Marc; Gibert, Fabien; Lloro, I.; Lobo, Alberto; Nofrarias, M.; Ramos Castro, Juan Jose
    Journal of physics: conference series
    Date of publication: 2012
    Journal article

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  • Mesh generation in FDTD: guidelines and applications

     Jauregui Telleria, Ricardo; Alvarez, Jesus; Silva Martinez, Fernando; Garcia, Salvador G
    International Journal on Communications Antenna and Propagation
    Date of publication: 2012-12
    Journal article

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  • LISA PathFinder radiation monitor proton irradiation test results

     Mateos, I.; Diaz Aguiló, Marc; Gibert, Fabien; Grimani, C.; Hollington, D.; Lloro, I.; Lobo, Alberto; Nofrarias, M.; Ramos Castro, Juan Jose
    Journal of physics: conference series
    Date of publication: 2012
    Journal article

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  • The LISA Pathfinder mission

     Diaz Aguiló, Marc; Ramos Castro, Juan Jose; [et, al]
    Classical and quantum gravity
    Date of publication: 2012-06-21
    Journal article

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  • Changes in heart rate variability indexes due to drowsiness in professional drivers measured in a real environment

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose; Rodríguez Ibáñez, Noelia; de la Cruz, M.A.F.
    Computing in Cardiology
    Presentation's date: 2012-09-12
    Presentation of work at congresses

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    The study aims to assess the changes in Heart Rate Variability (HRV) indexes in healthy subjects whi le driving in a real environment in order to detect drowsiness. The ECG of ten professional drivers was acquired while driving on routes familiar to the subjects. RR time series were quantified using a sliding window of 300 beats. Mean (mRR), standard devi ation (SDNN), standard deviation of the differentiated time series (rmsDD), power of the low (PLF) and high (PHF) frequency bands as well as the ratio LF/HF were computed. In addition, the median frequency of the power spectrum (MEDF), the bandwidth that c ontains the 50% of the power (BW50) and a measure of the asymmetry of the spectrum (AFS) were obtained. Moreover, the Hurst exponent estimated by fractional differintegration (HFDI) and the short scaling exponent obtained by detrended fluctuation analysis (α 1 ) were computed. Two observers classified the state of the drivers minute by minute by inspection of video recordings as alert or drowsy driver. Five subjects were alert for the whole recording while the others presented one or more periods of drowsines s in seven recordings between resting stops. There are not significant differences between groups for all indexes but BW50 (p<0.05). Nevertheless paired tests comparing drowsy and alert periods show significant differences (p<0.05) for SDNN, HFDI, mRR, BW 50 , AFS, α 1 , LF/HF and MEDF.

  • Cubesat-based demonstrator for optical Earth observation

     Jove Casulleras, Roger; Camps Carmona, Adriano Jose; Ramos Castro, Juan Jose
    IEEE International Geoscience and Remote Sensing Symposium
    Presentation's date: 2012-07-26
    Presentation of work at congresses

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    This paper introduces UPCSat-1 , the first project of the Universitat Politècnica de Catalunya to build and launch a pico-satellite. Its main scope is to develop, construct, assembly, test and launch into a Low Earth Orbit a CubeSat that will carry a simple optical payload and some technological demonstrators. On one hand, this is mainly an educational project in which the development of some of the subsystems is carried out by Master Thesis students. On the other hand, the satellite becomes an optimum platform to perform small scientific experiments, and to demonstrate some of the new technologies that it incorporates.

  • Minimally invasive in vivo human lung tissue bioimpedance measurements during the bronchoscopy procedure

     Sánchez, Benjamín; Vandersteen, Gerd; Martin, I.; Castillo, David; Torrego, A.; Riu Costa, Pere Joan; Schoukens, Johan; Bragos Bardia, Ramon
    IEEE Engineering in Medicine and Biology Society
    Presentation's date: 2012-08-28
    Presentation of work at congresses

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    Respiratory diseases, which include diseases of the lung, pleura, bronchial tree, trachea, upper respiratory tract and of the respiratory muscles and nerves, are a common and important cause of illness and death among the population. Experimental evidences have shown that tissue lesions have different electrical properties compared with normal tissue. Therefore, lung tissues lesions may be differentiated from lung normal tissue by comparing the tissue passive electrical properties. The manuscript reports a feasibility study for minimally invasive in vivo human lung tissue tetrapolar bioimpedance measurements using a catheter during the bronchoscopy procedure based on multisine Electrical Impedance Spectroscopy (EIS) at 10 kHz - 1 MHz.

  • Improvement of the actimetry agreement among sites by proper choice of signal processing stages

     Garcia Gonzalez, Miquel Angel; Giovinazzo, Giuseppe; Gomez Bule, Rafael; Landi, Francesca; Ramos Castro, Juan Jose; Rosell Ferrer, Francisco Javier
    IASTED International Conference Biomedical Engineering
    Presentation's date: 2012-02-15
    Presentation of work at congresses

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    Physical activity (PA) has been identified as a key health indicator and has been assessed in multiple studies as the study of cardiovascular diseases, diabetes mellitus, obesity and psychological conditions. For this reason the use of accelerometers to quantify PA is widely accepted in either clinical/laboratory settings as well as in freeliving environments. The use of accelerometers in the measurement of PA is a relatively new technique and, therefore, has been not standardized. The aim of this work is to study the influence of signal processing stages in the estimation of PA while measuring simultaneously in three different sites to provide robust indicators of activity in front of changes in site measurement. With our measurement we show that a proper choice of signal processing steps can improve the agreement among activity indices measured from different sites on the same individual. The results also show that the most suited index is the time above threshold. In this case, the best combination of axes is by applying the quadratic mean, the best filtering of axes is using a cut-off frequency of around 1.5 Hz and a threshold to compute the index of 0.04 g.

  • A wireless sensor network design for the Help4Mood european project

     Pérez Diaz de Cerio, David; Ruiz Boque, Silvia; Rosell Ferrer, Francisco Javier; Ramos Castro, Juan Jose; Castro Robles, Joan Carles
    European Wireless Conference
    Presentation's date: 2012-04
    Presentation of work at congresses

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    Help4Mood is a closed loop approach supporting the control, communication and treatment management of patients with Major Depression. The first out of the three main components of the Help4Mood solution is the Personal Monitoring System (PMS), a set of different wireless sensors whose data sink is centralized on a laptop. The objective of this PMS is to monitor the activity of the patients, so several sensors have been chosen to cover the needs of different individuals. These include a wrist watch, a key ring, a waist/belt sensor, an under mattress sensor and a cellular phone. This paper describes the first prototype and the results obtained from this Wireless Sensor Network.

  • A wireless under-mattress sensor system for sleep monitoring in people with major depression

     Mahdavi, Hadiseh; Ramos Castro, Juan Jose; Giovinazzo, Giuseppe; Garcia Gonzalez, Miquel Angel; Rosell Ferrer, Francisco Javier
    IASTED International Conference Biomedical Engineering
    Presentation's date: 2012-02-16
    Presentation of work at congresses

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    Monitoring people during sleep time is of particular interest to patients with sleep disorders and elderly people or infants. We have developed a battery powered electronic system to monitor people in the bed, store the data and send them through a wireless link to a PC. The resulting data will be subject to further analysis using pattern recognition to evaluate the feasibility of using the system as an indicator of sleep quality. The system is able to detect presence on the bed and movements and breathing of the patient. The changes in pressure distribution on the mattress cause changes in pressure in the layers of the sensor and a voltage will appear on the electrodes. The detection ability depends strongly on the shape of the mattress and the bedbase.

  • Unobtrusive activity measurement in patients with depression: the H4M approach

     Ramos Castro, Juan Jose; Mahdavi, Hadiseh; Pérez Diaz de Cerio, David; Garcia Gonzalez, Miquel Angel; Estevez, Soraya; Rosell Ferrer, Francisco Javier
    Information and Communication Technologies applied to Mental Health
    Presentation's date: 2012-10-04
    Presentation of work at congresses

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  • Access to the full text
    Electromagnetic interference prediction in an in-house power-line  Open access

     Samso, Margarita; Ribó, Miquel; Sánchez Delgado, Albert-Miquel; Regué, J.R.; Aragon Homar, Marc; Silva Martinez, Fernando
    International Symposium on Electromagnetic Compatibility
    Presentation's date: 2012-09-19
    Presentation of work at congresses

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    Abstract —In this paper a new methodology for the prediction of the conducted-emission propagation in an in-house power- line network is presented. This methodology is based on the modal S -parameter characterization of the devices present in the power-line network, as well as on the modal modeling of branch- line connections. The modal S parameters relate common- and di ff erential-mode waves, and give more information regarding interference propagation. With this methodology, common- and di ff erential-mode attenuations, and modal conversion between common and di ff erential modes can be accurately predicted, which is of great interest for power-line communication devel- opment and conducted-emission mitigation. This methodology is tested by accurately predicting the interference levels up to 100 MHz of an in-house power-line network composed by thermal- magnetic circuit breakers, residual-current circuit breakers, single-phase wires and light bulbs.

    Postprint (author’s final draft)

  • HRV based Health&Sport markers using video from the face

     Capdevila, Lluis; Moreno, Jordi; Movellan, Javier; Parrado Romero, Eva; Ramos Castro, Juan Jose
    IEEE Engineering in Medicine and Biology Society
    Presentation's date: 2012-08-28
    Presentation of work at congresses

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    Heart Rate Variability (HRV) is an indicator of health status in the general population and of adaptatio n to stress in athletes. In this paper we compare the performance of two systems to measure HRV: (1) A commercial system based on recording the physiological cardiac signal with (2) A computer vision system that uses a standard video images of the face to estimate RR from changes in skin color of the face. We show that the computer vision system performs surprisingly well. It estimates individual RR intervals in a non - invasive manner and with error levels comparable to those achieved by the physiological based system.

  • Help4Mood: testing and achievements of the first wireless sensor network prototype

     Pérez Diaz de Cerio, David; Ruiz Boque, Silvia; Rosell Ferrer, Francisco Javier; Ramos Castro, Juan Jose; Colomé Castellví, Josep Maria
    European Cooperative in Science And Technology
    Presentation's date: 2012-02-10
    Presentation of work at congresses

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    Help4Mood is a closed loop approach supporting the control, communication and treatment management of patients with Major Depression. The first out of the three main components of the Help4Mood solution is the Personal Monitoring System (PMS), a set of different wireless sensors whose data sink is centralized on a laptop. The objective of this PMS is to monitor the activity of the patients, so several sensors have been chosen to cover the needs of different individuals. These include a wrist watch, a key ring, a waist/belt sensor, an under mattress sensor and a cellular phone. This paper describes the first prototype and the results obtained from this Wireless Sensor Network

  • Securing an interoperability architecture for home and urban networking: Implementation of the security aspects in the INREDIS interoperability architecture

     Giménez, Rafael; Pous Sola, Marc; Rico Novella, Francisco Jose
    IEEE International Conference on Advanced Information Networking and Applications
    Presentation's date: 2012
    Presentation of work at congresses

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  • A novel index based on fractional calculus to assess the dynamics of heart rate variability: changes due to chi or yoga meditations

     Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Fernandez Chimeno, Mireya
    Computing in Cardiology
    Presentation's date: 2012-09-12
    Presentation of work at congresses

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    The study aims to present and interpret a novel index based on fractional calculus (c) and to assess differences in RR time series dynamics in subjects during meditation. Fractional differintegration (FDI) of a RR time series provides a new time series. c is defined as the order of the FDI operator that provides the time series with minimum variance. Analyzed time series were obtained from the Exaggerated Heart Rate Oscillations During Two Meditation Techniques database. This database contains RR time series before and after Chi Meditation and Kundalini Yoga. It also contains recordings of elite athletes and healthy subjects while sleeping and during metronomic breathing at 0.25 Hz. c is significantly higher during Chi or Yoga meditation when compared with the recordings before the meditation starts or in subjects while sleeping or during metronomic breathing. 2012 CCAL.

    The study aims to present and interpret a novel index based on fractional calculus ( αc) and to assess differences in RR time series dynamics in subjects during meditation. Fractional differintegration (FDI) of a RR time series provides a new time series.αc is defined as the order of the FDI operator that provides the time series with minimum variance. Analyzed time series were obtained from the Exaggerated Heart Rate Oscillations During Two Meditation Techniques database. This database contains RR time series before and after Chi Meditation and Kundalini Yoga. It also contains recordings of elite athletes and healthy subjects while sleeping and during metronomic breathing at 0.25 Hz. αc is significantly higher during Chi or Yoga meditation when compared with the recordings before the meditation starts or in subjects while sleeping or during metronomic breathing.

  • Heart rate variability analysis using a seismocardiogram signal

     Ramos Castro, Juan Jose; Moreno, J.; Miranda-Vidal, H.; Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Rodas, G.; Capdevila, L.
    IEEE Engineering in Medicine and Biology Society
    Presentation's date: 2012-08-31
    Presentation of work at congresses

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    Seismocardiography is a simple and non invasive method of recording cardiac activity fro m the movements of the body caused by heart pumping. In this preliminary study we use a smartphone to record this acceleration and estimate the heart rate. We compare the heart rate variability parameters from the seismocardi ogram and ECG reference signal. The results show a great similarity and are strongly influenced by the instability in the sampling frequency of the device. The differences between RR series are lower than 10 ms.

  • Método y sistema para inferir el comportamiento o estado del conductor de un vehículo, uso del método y programa informático para llevar a cabo el método

     Fernandez Chimeno, Mireya; Bandez Martinez, Daniel; Bartra Cisa, Ariadna; Marco Colas, Santiago; Ramos Castro, Juan Jose
    Date of request: 2012-02-01
    Invention patent

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  • Método con bio-retroalimentacion para entrenamiento de la musculatura del suelo pelvico

     Mañanas Villanueva, Miguel Angel; Ramos Castro, Juan Jose; Espuña Pons, Montserrat; Perez Gonzalez, Amelia
    Date of request: 2012-07-16
    Invention patent

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    Método con bio-retroalimentación para entrenamiento de la musculatura del suelo pélvico.

    Aplicable al tratamiento de incontinencia urinaria, incontinencia fecal y prolapso de órganos pélvicos, utilizando un dispositivo electrónico portátil para captura mediante sensores de señales EMG de actividad abdominal y de la zona a tratar durante unos ejercicios musculares presentando visual y/o acústicamente unos resultados comprendiendo el método: la colocación de un sensor vaginal o rectal (10) y de dos sensores (11) en la zona baja abdominal, la ejecución de ejercicios trabajando la musculatura del suelo pélvico, la indicación de evaluaciones sobre los ejercicios realizados y el almacenamiento de resultados. La colocación de los sensores la realiza la propia usuaria, evaluando el dispositivo la correcta colocación de sensores con indicación mediante dichos medios acústicos y/o visuales, a la usuaria de que se ha alcanzado un posicionado adecuado, y realizando una etapa previa a los ejercicios de adquisición del tono muscular.

  • Sistema combinado de análisis de parámetros fisiológicos, cognitivos y conductuales basado en plataformas móviles

     Fernandez Chimeno, Mireya; Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose
    Participation in a competitive project

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  • Monitorización del patrón ventilatorio (PV) mediante tomografía por impedancia eléctrica (TIE) en paciente con enfermedad pulmonar obstructiva crónica (EPOC)  Open access

     Balleza Ordaz, José Marco
    Defense's date: 2012-07-20
    Department of Automatic Control, Universitat Politècnica de Catalunya
    Theses

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    El objetivo de esta investigación fue obtener un modelo matemático de calibración que permita estimar cuantitativamente el patrón ventilatorio (PV), en términos de volumen, en un grupo de voluntarios sanos y pacientes con enfermedad pulmonar obstructiva crónica (EPOC). Todo ello a partir de la información regional de la variación temporal de impedancia eléctrica obtenida con el equipo TIE4sys (sistema de tomografía por impedancia eléctrica), prescindiendo de la calibración individual con un neumotacómetro. Para lograr este objetivo la presente investigación se dividió en dos etapas. La primera etapa consistió en obtener y evaluar un grupo de ecuaciones de calibración utilizando 7 regiones de interés (ROI) en un grupo de voluntarios sanos (hombres y mujeres). La primera ROI incluyó todos los elementos de la imagen TIE. Dos ROI fueron definidas usando solamente los pixeles con variación superior al 70% y 30% de la máxima (método porcentajes). Dos fueron obtenidas definiendo el contorno de forma manual (método mouse) usando como referencia las ROI anteriores. Las dos últimas fueron máscaras elípticas con excentricidad 0,8 y eje mayor de 32 y 25 pixeles, respectivamente. En el caso de hombres, la media del coeficiente de determinación (R2) de las ecuaciones de calibración fue de 93 ± 5%. Los parámetros comunes en todas ellas fueron el pliegue subescapular y peso. Las menores dispersiones en la estimación de volumen se obtuvieron usando todos los elementos de la imagen, la ROI reducida al 70% con el método porcentajes y ambas máscaras elípticas. El valor medio de dichas dispersiones fue del 8%. En el caso de mujeres se analizaron 4 grupos: el grupo total y 3 que resultaron de estratificar la muestra en función al IMC. La media del R2 de todas las ecuaciones de calibración fue del 58 ± 12%. El parámetro más significativo en todas ellas fue la edad. En todos los grupos de mujeres se obtuvieron dispersiones en la estimación de volumen muy elevadas cuyo valor medio fue del 28 ± 5%.

    The goal of this research is to obtain a mathematical calibration model to estimate, in a quantitative way and in terms of volume, the ventilatory pattern in a group of healthy volunteers and chronic obstructive pulmonary disease (COPD) patients. Several models were built from the changes on the regional electrical impedance obtained by TIE4sys (electrical impedance tomograph), without requiring an individual calibration with a pneumotachometer. In order to achieve this aim, the research was divided into 2 parts. The first part involved obtaining and assessing a set of calibration equations, using 7 regions of interest (ROI), in a group of healthy volunteers (males and females). The first ROI included all EIT image elements. Two ROI were defined by only including the pixels displaying changes larger than 70% and 30% of the maximum value of pixel change (percentage method). Two were determined by defining the region boundaries manually (mouse method), using as a reference the above ROI. The remaining two were elliptical masks with eccentricity of 0,8 and major axis of 32 and 25 pixels, respectively. In the case of healthy males, the mean value of the determination coefficients (R2) of all calibration equations was 93±5%. The parameters appearing in all of them were the subscapular skinfold and the weight. The smallest volume estimation dispersions obtained with TIE4sys were those using all elements of ROI, the reduced ROI by percentage method to 70% and both elliptical masks. The mean value of these volume estimation dispersions was of 8%. The group of female volunteers was further divided in 4 groups, one including all females and 3 groups obtained from the stratification of the sample according to BMI. The mean value of R2 of all calibration equations was of 58±12%. The most significant parameter involved in all of them was the age. The dispersion in the estimation of volume for all groups was of 28±3%.The second part involved the assessment of the previous healthy male calibration equations in a group of COPD patients. Preliminary results showed an underestimation of volume estimations obtained by TIE4sys. Due to this fact, a set of adjustment mathematical models were obtained in order to improve the estimation of volume. The mean value of R2 of all adjustment equations obtained in this group was 87±7%. The most significant parameters involved in these equations were subscapular skinfold and weight. The smallest volume estimation dispersions by TIE4sys were obtained by using the elliptical mask with major axis of 25 pixels. The mean value of these dispersions was 14±1%. Furthermore, a subgroup of patients for which all pulmonary function tests (PFT) were available, was analyzed. The mean value of R2 of all adjustment equations obtained in this sample was 88±6%. From all PFT parameters, only the pressure of carbon dioxide in arterial blood (PCO2) was involved in 4 of 7 adjustment equations obtained in this group. The mean value of volume dispersions obtained by TIE4sys, using this 4 equations, was of 19±6%. This value is higher than the one obtained for the whole group. Conclusion. The mathematical adjustment of the calibration equations for healthy males was better than the one obtained for females. This fact highlighted that the anthropometric parameters used in the male group were statistically significant, while they were not for females. For this reason, larger volume estimation dispersions were obtained in this latter group. In the case of COPD patients, all healthy male calibration equations were improved by a mathematical adjustment model. In this case, the smallest volume estimation dispersions were obtained by using the elliptical mask with major axis of 25 pixels. The results obtained in the group of healthy males and COPD patients have been encouraging and it leads us to think that EIT technique can become part of PFT. In the case of females additional efforts should be made to find a calibration equation

  • Pla de transferencia tecnologica pttu de la Univeristat Politècnica de Catalunya

     Silva Martinez, Fernando
    Participation in a competitive project

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  • New indices for quantification of the power spectrum of heart rate variability time series without the need of any frequency band definition

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Ferrer, J; Escorihuela, R.M.; Parrado Romero, Eva; Capdevila, L; Benitez, A; Angulo, R; Rodriguez, F. A.; Iglesias, X; Bescós, R.; Marina, M; Padullés, M.; Ramos Castro, Juan Jose
    Physiological measurement
    Date of publication: 2011-06-07
    Journal article

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    This paper presents a new family of indices for the frequency domain analysis of heart rate variability time series that do not need any frequency band definition. After proper detrending of the time series, a cumulated power spectrum is obtained and frequencies that contain a certain percentage of the power below them are identified, so median frequency, bandwidth and a measure of the power spectrum asymmetry are proposed to complement or improve the classical spectral indices as the ratio of the powers of LF and HF bands (LF/HF). In normal conditions the median frequency provides similar information as the classical indices, while the bandwidth and asymmetry can be complementary measures of the physiological state of the tested subject. The proposed indices seem to be a good choice for tracking changes in the power spectrum in exercise stress, and they can guide in the determination of frequency band limits in other animal species.