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  • Healthy Life style and Drowsiness Prevention-HEALING DROP

     Fernandez Chimeno, Mireya
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  • 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.

  • Healthy Life style and Drowsiness Prevention-HEALING DROP

     Fernandez Chimeno, Mireya
    Participation in a competitive project

     Share

  • 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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    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.

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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.

  • 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.

  • 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.

  • 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

  • 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
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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.

  • 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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  • 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.

  • Healthy Life style and Drowsiness Prevention-HEALING DROP

     Ramos Castro, Juan Jose; Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya
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  • Sondas para la medida simultánea de campos eléctricos y magnéticos de alta intensidad en campo próximo y en el dominio del tiempo

     Silva Martinez, Fernando; Fernandez Chimeno, Mireya; Riu Costa, Pere Joan
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    Drowsiness detection by thoracic effort signal snalysis with professional drivers in real environments  Open access

     Rodríguez Ibáñez, Noelia; Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Fernandez Chimeno, Mireya
    International Conference on Driver Distraction and Inattention
    Presentation's date: 2011-09-06
    Presentation of work at congresses

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    Objective : The aim of this work is to develop a new index to assess the alertness state of drivers based on the respiratory dynamics derived f rom an inductive band. Background : Detection of drowsiness while driving is a leadin g objective in advanced driver assistance systems. A biomedical variable like thor acic 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. The refore, they may be especially useful to collect detailed information of the drowsiness state and an ticipate risky situations while driving. Method : The experiment described in this paper allows us to study how drivers react in strenuous conditions, in which they tend to get fat igued and drowsy, but struggle against falling asleep. The respiration data used in this s tudy was recordered by doing 72 hours of simulation driving test and 100 hours of real vehic le tests in real environment. Results : The results demonstrate the viability of drowsine ss detection in real vehicle using thoracic effort signal. The proposed method has a s ensitivity of 93.7% and specificity of 86.3% in detecting full awake drivers while it has a sens itivity of 83.1% and specificity of 95.3% in detecting drowsy drivers. Conclusions : The proposed index may be promising to assess the alertness state of real drivers. Applications : The potential applications of the algorithm are t o detect drowsiness states while driving and give an alarm in commercial fleets or p rofessional drivers to assure the integrity of the driver.

    Postprint (author’s final draft)

  • Contribution to long term telemetry in small laboratory animals

     Zabaco Natali, Oscar
    Defense's date: 2011-09-07
    Department of Automatic Control, Universitat Politècnica de Catalunya
    Theses

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  • Drowsiness detection by thoracic effort signal analysis in real driving environments

     Rodríguez Ibáñez, Noelia; Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    IEEE Engineering in Medicine and Biology Society
    Presentation's date: 2011-09-02
    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 respiratory dynamics derived from an inductive band. More than 100 hours of driving in real environments from 13 healthy subjects were analyzed. The proposed method has a sensitivity of 93.7% and specificity of 86.3% in detecting full awake drivers while it has a sensitivity of 83.1% and specificity of 95.3% in detecting drowsy drivers. The results show that the proposed index may be promising to assess the alertness state of real drivers.

  • The Effect of Electrocardiographic Lead Choice on RR Time Series

     Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Fernandez Chimeno, Mireya
    IEEE Engineering in Medicine and Biology Society
    Presentation's date: 2011-08-31
    Presentation of work at congresses

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    Results of heart rate variability analysis depend on the quality of the initial RR time series that is measured only in one lead of the ECG. This work shows that RR time series can subtly change from lead to lead so the choice of the analyzed lead is another source of uncertainty. The standard deviation of the differences of two RR time series obtained from different leads can change from 0.5 ms to more than 20 ms depending on the amount of noise, the morphological changes of the QRS complexes, the strategies of fiducial point determination and the measured subject. This source of uncertainty is in healthy subjects greater than that associated to the sampling frequency of the ECG for sampling frequencies greater than 400 Hz.

  • Transient perturbation analysis in digital radio

     Jauregui Telleria, Ricardo; Pous Sola, Marc; Fernandez Chimeno, Mireya; Silva Martinez, Fernando
    European Symposium on Electromagnetic Compatibility
    Presentation's date: 2010-07-26
    Presentation of work at congresses

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  • Method and system for determining an individual's state of attention

     Rodríguez Ibáñez, Noelia; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose; Garcia Gonzalez, Miquel Angel; Montseny Masip, Eduard; Bande Martinez, Daniel
    Date of request: 2010-08-03
    Invention patent

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  • Sistema modular para la alimentación por campo magnético en telemetría animal

     Zabaco Natalí, Oscar; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    Date of request: 2010-06-11
    Invention patent

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    La presente invención se refiere a un sistema modular (1) para proporcionar energía a un dispositivo electrónico (2) a través de un campo magnético.

    El dispositivo electrónico (2) es un implante para animales de laboratorio cuya misión es medir y enviar información de funciones fisiológicas del animal para un posterior análisis y estudio. El implante posee un módulo de almacenamiento de energía temporal.

    El subsistema que proporciona energía a través del campo magnético para la alimentación del implante está alojado en la jaula del animal y su modularidad permite aplicarlo a alojamientos animales tan grandes como se desee.

    El sistema modular permite estudios de duración prolongada, (en los cuales el uso de baterías está descartado), mientras el animal se mueve libremente en su jaula sin ningún tipo de restricción. El sistema modular permite además extraer el animal de la zona de generación de campo magnético durante periodos de tiempo limitados sin que se pierdan las funciones del implante por falta de alimentación.

  • Método y sistema de medida de parámetros fisiológicos

     Rodríguez Ibáñez, Noelia; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose; Garcia Gonzalez, Miquel Angel; Montseny Masip, Eduard; Bande Martínez, Daniel
    Date of request: 2010-12-24
    Invention patent

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    Método de determinación de al menos un parámetro fisiológico de un individuo conductor, piloto u operador de un vehículo o sistema de transporte o de defensa, que comprende: a) inyectar o inducir corriente en dicho individuo; b) medir en dicho individuo un parámetro eléctrico indicativo de su impedancia, comprendiendo: b1) medir el parámetro eléctrico con al menos dos pares de electrodos inyector-detector; b2) determinar la señal de impedancia a partir del parámetro eléctrico medido; b3) de entre las señales de impedancia determinadas, identificar aquéllas que tienen un origen fisiológico; y b4) seleccionar el par de electrodos que dan lugar a la señal de impedancia de mayor calidad; y c) derivar a partir de la señal de impedancia de mayor calidad dicho parámetro fisiológico.

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    RFID systems in medical environment: EMC issues  Open access

     Fernandez Chimeno, Mireya; Silva Martinez, Fernando
    European Symposium on Electromagnetic Compatibility
    Presentation's date: 2010-09
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    RFID is a promising technology in the healthcare area in order to improve patient safety and increase efficiency and reduce costs in the daily healthcare work. This paper analyzes the available literature regarding both interference of RFID systems in medical equipment and the interferences of medical equipment on RFID systems. The conclusion of this analysis is that is necessary to develop standards in order to protect medical equipment from RFID interferences, and standards to plan the deployment of RFID installations taking into account electromagnetic compatibility issues.

  • Mobile phones electromagnetic interference in medical environments: a review

     Fernandez Chimeno, Mireya; Silva Martinez, Fernando
    European Symposium on Electromagnetic Compatibility
    Presentation's date: 2010-07-28
    Presentation of work at congresses

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    This paper presents a review of the effect of electromagnetic interferences of mobile phones in medical environment. The review is focussed in two areas, EMI in implantable devices like pacemakers or ICD, and EMI in medical equipment in hospital areas with life supporting equipment like intensive care units (ICU) or operating rooms (OR). The applied methodology for interference testing is different for all the analyzed studies, and the results range from 100% of interfered devices to no effect. The majority of authors recommend maintaining a safety distance both between cellular phones and medical devices. Also, it is necessary to establish clear policies for the use of mobile phones in critical areas in hospitals. Finally, it is necessary to develop a family of EMC standards for testing insitu the effects of non-medical devices inside medical facilities. This will permit medical staff to take profit from new technologies in their daily work in a safe way.

  • Un método rápido para la cuantificación de la autosemejanza de corto alcance en series RR

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    Congreso Anual de la Sociedad Española de Ingeniería Biomédica
    Presentation's date: 2010-11-26
    Presentation of work at congresses

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    RFID system evaluation against radiated transient noise  Open access

     Pous Sola, Marc; Fernandez Chimeno, Mireya; Silva Martinez, Fernando
    European Symposium on Electromagnetic Compatibility
    Presentation's date: 2010-09-13
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    In this paper a radiofrequency identification system according to standard ISO/IEC 14443 type-B is evaluated in presence of transient noise. This real time communication system working at 13.56 MHz is interfered in a controlled environment by different transient bursts varying their level, frequency and duration. The transient burst interference is applied in an AC main wire close to the system and the effect over the digital communication system is evaluated using two different methods. The first one is observing directly an RFID equipment in presence of transient signals, and the second one is capturing the interference in time domain an evaluating its effect by means of simulation. The RFID system is affected by these transient noises causing different types of errors. It is shown that it is essential to measure and evaluate in time domain the transient phenomena to ensure that the RFID system do not have susceptibility problems.

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    A new and fast index for the quantification of short range self-similarity in RR time series  Open access

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    Computing in Cardiology
    Presentation's date: 2010-09-27
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    We propose a new and very fast index (the frequency of sign changes of the mirrored differences or fscmd) with good correlation with the short range scaling exponent (  R) estimated among scales 4 to 16 of the DFA. fscmd computes the relative number of sign changes of the difference of the RR time series minus their corresponding reversed RR time series after a moving average detrending procedure is applied using a window of 30 samples. Linear regression results with simulated time series with Fractional Brownian Noise and with actual time series using the Fantasia (FT), Normal Sinus Rhythm RR time series (NSR) and Congestive Heart Failure RR interval (CHF) databases after artifact correction show good agreement between fscmd and  R. Finally, Mann-Whitney Rank Sum tests applied to  R and fscmd when comparing NSR and CHF databases show very significant differences (p<0.001) between groups for both indices.

  • Errors in the Estimation of Approximate Entropy and Other Recurrence-Plot-Derived Indices Due to the Finite Resolution of RR Time Series

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    IEEE transactions on biomedical engineering
    Date of publication: 2009-02
    Journal article

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  • Biofeedback per entrenament del sòl pèlvic en malalts amb incontinència urinària

     Mañanas Villanueva, Miguel Angel; Alonso López, Joan Francesc; Caminal Magrans, Pedro; Fernandez Chimeno, Mireya; Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Rojas Martínez, Mónica; Romero Lafuente, Sergio
    Participation in a competitive project

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  • SISTEMA DE ANALISIS DE PARAMETROS FISIOLOGICOS INDICADORES DE SALUD, APLICACION A RESULTADOS EN HUMANOS Y ANIMALES

     Fernandez Chimeno, Mireya; Garcia Gonzalez, Miquel Angel; Vargas Drechsler, Manuel Agustin; Ramos Castro, Juan Jose
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  • GRUP D'INSTRUMENTACIÓ ELECTRÒNICA I BIOMÈDICA: Grup de Recerca Consolidat.

     Bragos Bardia, Ramon; Rosell Ferrer, Francisco Javier; Fernandez Chimeno, Mireya; Garcia Gonzalez, Miquel Angel; Nescolarde Selva, Lexa Digna; Ramos Castro, Juan Jose; Riu Costa, Pere Joan; Robert i Sanxis, Francesc Josep; Silva Martinez, Fernando; Torrents Dolz, Josep Maria
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    Car windshield behavior transient analysis by FDTD  Open access

     Jauregui Telleria, Ricardo; Pous Sola, Marc; Vives, Yolanda; Fernandez Chimeno, Mireya; Riu Costa, Pere Joan; Silva Martinez, Fernando
    European Symposium on Electromagnetic Compatibility
    Presentation's date: 2009-06
    Presentation of work at congresses

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    The present article studies the influence of a car heatable windshield by means of an equivalent material that allows an appropriate meshing of the vehicle. This study has been performed analyzing the propagation of an electromagnetic radiated transient pulse generated by a wire inside a car with and without the windshield. The Finite Differences Time Domain (FDTD) is the method used to obtain the field coupled to antennas located inside and outside the car. We concluded that it is important to take into account the heatable windshield to make a suitable electromagnetic model of the vehicle.

  • An Empirical Methodology for the Definition of Frequency Bands for Spectral Analysis of Heart Rate Variability in Animals: Application to Sprague-Dawley Rats

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Escorihuela, R.M.; Capdevila, L.; Ramos Castro, Juan Jose
    World Congress on Medical Physics and Biomedical Engineering
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    Obtención empírica del límite frecuencial entre las bandas de baja y altra frecuencia en análisis de variabilidad del ritmo cardíaco: aplicación en ratas y humanos  Open access

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Escorihuela, R.M.; Capdevila, Lluis; Ramos Castro, Juan Jose
    Congreso Anual de la Sociedad Española de Ingeniería Biomédica
    Presentation's date: 2009-11
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    Se propone un nuevo método para la determinación empírica de los límites entre las bandas de baja frecuencia y alta frecuencia del espectro de potencia de las series RR en los estudios de variabilidad del ritmo cardíaco. El método se ha aplicado a series RR obtenidas en humanos y ratas Sprague-Dawley. Para humanos el límite coincide con la recomendación de 0,15 Hz mientras que para ratas Sprague-Dawley la metodología empleada sugiere un límite de 0,75 Hz.

  • Método y sistema para determinar el estado de atención de un individuo

     Rodríguez Ibáñez, Noelia; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose; Garcia Gonzalez, Miquel Angel; Montseny Masip, Eduard; Bande Martínez, Daniel
    Date of request: 2009-08-03
    Invention patent

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  • Cuantificación de la estabilidad de la media y la varianza en series RR: aplicación a registros en reposo y durante el ejercicio de intensidad moderada

     Garcia Gonzalez, Miquel Angel; Marine, M Ocaña; Benítez, A Herrera; Fernandez Chimeno, Mireya; Rodas, G Font; Rodríguez, F A Guisado; Ramos Castro, Juan Jose
    Congreso Anual de la Sociedad Española de Ingeniería Biomédica
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  • Normalization of the standard deviation and spectral indices of RR time series for comparison among situations with different mean heart rate

     García-González, M A; Garcia Gonzalez, Miquel Angel; Fernández-Chimeno, M; Fernandez Chimeno, Mireya; Capdevila, L; Ocaña, M; Rodas, G; Ramos Castro, Juan Jose
    European Conference of the International Federation for Medical and Biological Engineering
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  • Validation of low-level, high-frequency transient FDTD simulation with radiated field measurements

     Jauregui Telleria, Ricardo; Pous Sola, Marc; Fernandez Chimeno, Mireya; Riu Costa, Pere Joan; Silva Martinez, Fernando
    European Symposium on Electromagnetic Compatibility
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  • A Near-Field Probe for In Situ EMI Measurements of Industrial Installations

     Quilez Figuerola, Marcos; Atienza Picola, Andreu; Fernández-Chimeno, Mireya; Fernandez Chimeno, Mireya; Riu Costa, Pere Joan; Silva Martinez, Fernando; Aragon Homar, Marc
    IEEE transactions on electromagnetic compatibility
    Date of publication: 2008-11
    Journal article

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    Estimation of the uncertainty in time domain indices of RR time series  Open access

     Garcia-Gonzalez, M A; Garcia Gonzalez, Miquel Angel; Fernandez-Chimeno, M; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    IEEE transactions on biomedical engineering
    Date of publication: 2007-03
    Journal article

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    A method for estimating the uncertainty in time-domain indices of RR time series is described. The method relies on the central limit theorem that states that the distribution of a sample average of independent samples has an uncertainty that asymptotically approaches to the sample standard deviation divided by the square root of the number of samples. Because RR time series cannot be characterized by a set of independent samples, we propose to estimate the uncertainty of indices by computing them in blocks that satisfy that the obtained partial indices are independent. We propose a methodology to search sets of independent partial indices and apply this methodology to the estimation of the uncertainty in the mean RR, SDRR, and r-msDD indices. The results show that the uncertainty can be higher than the 10% of the index for the SDRR and even higher for the r-msDD. Moreover, a statistical test for the difference of two indices is proposed.

  • Time domain ambient interferences analysis

     Velasco, S; Fernandez Chimeno, Mireya; Silva Martinez, Fernando; Verdaguer Massana, Salvador
    EMC EUROPE WORKSHOP ON WIRELESS SYSTEMS
    Presentation of work at congresses

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  • Medical Equipment Immunity Assessment by Time Domain Analysis. Applications to GSM signals

     Fernández-Chimeno, M; Fernandez Chimeno, Mireya; García-González, M A; Garcia Gonzalez, Miquel Angel; Silva Martinez, Fernando
    IEEE International Symposium on Electromagnetic Compatibility
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  • Heart Graft Rejection Assessed by Multi-Frequency Electrical Impedance: Human Results

     Rosell Ferrer, Francisco Javier; Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Bragos Bardia, Ramon; Salazar, Y.; Fernandez Chimeno, Mireya; Viñolas, X.; Cinca Cosculluela, Juan
    International Conference on Electrical Bio-impedance
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    FDTD analysis of SAR from a cell phone inside a vehicle by numerical computation  Open access

     Anzaldi, G; Silva Martinez, Fernando; Fernandez Chimeno, Mireya; Quilez Figuerola, Marcos; Riu Costa, Pere Joan
    IEEE transactions on biomedical engineering
    Date of publication: 2007-05
    Journal article

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    The purpose of this paper is to analyze the influence of the metallic structures of a realistic car body frame on the specific absorption rate (SAR) produced by a cell phone when a complete human body model is placed at different locations inside the vehicle, and to identify the relevant parameters responsible for these changes. The modeling and analysis of the whole system was conducted by means of computer simulations based on the full wave finite-difference time-domain (FDTD) numerical method. The excitation considered was an 835 MHz 2 dipole located as a handsfree communication device or as a hand-held portable system. We compared the SAR at different planes on the human model, placed inside the vehicle with respect to the free space situation. The presence of the car body frame significantly changes the SAR distributions, especially when the dipole is far from the body. Although the results are not conclusive on this point, this change in SAR distribution is not likely to produce an increase above the limits in current guidelines for partial body exposure, but may be signifi- cant for whole-body exposure. The most relevant change found was the change in the impedance of the dipole, affecting the radiated power. A complementary result from the electromagnetic computations performed is the change in the electromagnetic field distribution inside a vehicle when human bodies are present. The whole vehicle model has been optimized to provide accurate results for sources placed inside the vehicle, while keeping low requirements for computer storage and simulation time.