The Experts below are selected from a list of 174 Experts worldwide ranked by ideXlab platform

Ki H. Chon - One of the best experts on this subject based on the ideXlab platform.

  • Respiratory rate extraction from pulse oximeter and electrocardiographic recordings
    Physiological Measurement, 2011
    Co-Authors: Jinseok Lee, John P. Florian, Ki H. Chon
    Abstract:

    We present an algorithm of respiratory rate extraction using particle filter (PF), which is applicable to both photoplethysmogram (PPG) and electrocardiogram (ECG) signals. For the respiratory rate estimation, 1 min data are analyzed with combination of a PF method and an autoregressive model where among the resultant coefficients, the corresponding Pole Angle with the highest magnitude is searched since this reflects the closest approximation of the true breathing rate. The PPG data were collected from 15 subjects with the metronome breathing rate ranging from 24 to 36 breaths per minute in the supine and upright positions. The ECG data were collected from 11 subjects with spontaneous breathing ranging from 36 to 60 breaths per minute during treadmill exercises. Our method was able to accurately extract respiratory rates for both metronome and spontaneous breathing even during strenuous exercises. More importantly, despite slow increases in breathing rates concomitant with greater exercise vigor with time, our method was able to accurately track these progressive increases in respiratory rates. We quantified the accuracy of our method by using the mean, standard deviation and interquartile range of the error rates which all reflected high accuracy in estimating the true breathing rates. We are not aware of any other algorithms that are able to provide accurate respiratory rates directly from either ECG signals or PPG signals with spontaneous breathing during strenuous exercises. Our method is near real-time realizable because the computational time on 1 min data segment takes only 10 ms on a 2.66 GHz Intel Core2 microprocessor; the data are subsequently shifted every 10 s to obtain near-continuous breathing rates. This is an attractive feature since most other techniques require offline data analyses to estimate breathing rates.

  • An Autoregressive Model-Based Particle Filtering Algorithms for Extraction of Respiratory Rates as High as 90 Breaths Per Minute From Pulse Oximeter
    IEEE Transactions on Biomedical Engineering, 2010
    Co-Authors: Ki H. Chon
    Abstract:

    We present particle filtering (PF) algorithms for an accurate respiratory rate extraction from pulse oximeter recordings over a broad range: 12-90 breaths/min. These methods are based on an autoregressive (AR) model, where the aim is to find the Pole Angle with the highest magnitude as it corresponds to the respiratory rate. However, when SNR is low, the Pole Angle with the highest magnitude may not always lead to accurate estimation of the respiratory rate. To circumvent this limitation, we propose a probabilistic approach, using a sequential Monte Carlo method, named PF, which is combined with the optimal parameter search (OPS) criterion for an accurate AR model-based respiratory rate extraction. The PF technique has been widely adopted in many tracking applications, especially for nonlinear and/or non-Gaussian problems. We examine the performances of five different likelihood functions of the PF algorithm: the strongest neighbor, nearest neighbor (NN), weighted nearest neighbor (WNN), probability data association (PDA), and weighted probability data association (WPDA). The performance of these five combined OPS-PF algorithms was measured against a solely OPS-based AR algorithm for respiratory rate extraction from pulse oximeter recordings. The pulse oximeter data were collected from 33 healthy subjects with breathing rates ranging from 12 to 90 breaths/ min. It was found that significant improvement in accuracy can be achieved by employing particle filters, and that the combined OPS-PF employing either the NN or WNN likelihood function achieved the best results for all respiratory rates considered in this paper. The main advantage of the combined OPS-PF with either the NN or WNN likelihood function is that for the first time, respiratory rates as high as 90 breaths/min can be accurately extracted from pulse oximeter recordings.

L.m. Patnaik - One of the best experts on this subject based on the ideXlab platform.

  • Parametric technique for P wave delineation
    Proceedings of ICASSP '94. IEEE International Conference on Acoustics Speech and Signal Processing, 1994
    Co-Authors: B. Madhukar, K. Rajgopal, L.m. Patnaik
    Abstract:

    The electrocardiogram (ECG), which represents the electrical activity of the heart, is widely used for the diagnosis of cardiac diseases. The ECG typically consists of three important component waves, called the P, QRS, and T waves, which provide clinical information about the functioning of the heart. An important problem in ECG signal processing is that of delineation of the ECG component waves. The delineation of the P wave is difficult in certain cardiac diseases where the P wave overlaps the other ECG component waves. We present an innovative algorithm, for the delineation of the P waves, which works well even in such cases. The algorithm basically consists of Pole-zero modeling of the discrete cosine transformed ECG. The resulting Pole-zero filter is then decomposed into a set of unique partial fractions (PF), with each PF representing a sub-component or a fractional component (FC) of the ECG. A Pole Angle template matching procedure is used to identify the PFs of the QRS and T waves, and then their corresponding FCs are subtracted from the ECG to leave the P wave as the residue.

  • ICASSP (3) - Parametric technique for P wave delineation
    Proceedings of ICASSP '94. IEEE International Conference on Acoustics Speech and Signal Processing, 1994
    Co-Authors: B. Madhukar, K. Rajgopal, L.m. Patnaik
    Abstract:

    The electrocardiogram (ECG), which represents the electrical activity of the heart, is widely used for the diagnosis of cardiac diseases. The ECG typically consists of three important component waves, called the P, QRS, and T waves, which provide clinical information about the functioning of the heart. An important problem in ECG signal processing is that of delineation of the ECG component waves. The delineation of the P wave is difficult in certain cardiac diseases where the P wave overlaps the other ECG component waves. We present an innovative algorithm, for the delineation of the P waves, which works well even in such cases. The algorithm basically consists of Pole-zero modeling of the discrete cosine transformed ECG. The resulting Pole-zero filter is then decomposed into a set of unique partial fractions (PF), with each PF representing a sub-component or a fractional component (FC) of the ECG. A Pole Angle template matching procedure is used to identify the PFs of the QRS and T waves, and then their corresponding FCs are subtracted from the ECG to leave the P wave as the residue. >

B. Madhukar - One of the best experts on this subject based on the ideXlab platform.

  • Parametric technique for P wave delineation
    Proceedings of ICASSP '94. IEEE International Conference on Acoustics Speech and Signal Processing, 1994
    Co-Authors: B. Madhukar, K. Rajgopal, L.m. Patnaik
    Abstract:

    The electrocardiogram (ECG), which represents the electrical activity of the heart, is widely used for the diagnosis of cardiac diseases. The ECG typically consists of three important component waves, called the P, QRS, and T waves, which provide clinical information about the functioning of the heart. An important problem in ECG signal processing is that of delineation of the ECG component waves. The delineation of the P wave is difficult in certain cardiac diseases where the P wave overlaps the other ECG component waves. We present an innovative algorithm, for the delineation of the P waves, which works well even in such cases. The algorithm basically consists of Pole-zero modeling of the discrete cosine transformed ECG. The resulting Pole-zero filter is then decomposed into a set of unique partial fractions (PF), with each PF representing a sub-component or a fractional component (FC) of the ECG. A Pole Angle template matching procedure is used to identify the PFs of the QRS and T waves, and then their corresponding FCs are subtracted from the ECG to leave the P wave as the residue.

  • ICASSP (3) - Parametric technique for P wave delineation
    Proceedings of ICASSP '94. IEEE International Conference on Acoustics Speech and Signal Processing, 1994
    Co-Authors: B. Madhukar, K. Rajgopal, L.m. Patnaik
    Abstract:

    The electrocardiogram (ECG), which represents the electrical activity of the heart, is widely used for the diagnosis of cardiac diseases. The ECG typically consists of three important component waves, called the P, QRS, and T waves, which provide clinical information about the functioning of the heart. An important problem in ECG signal processing is that of delineation of the ECG component waves. The delineation of the P wave is difficult in certain cardiac diseases where the P wave overlaps the other ECG component waves. We present an innovative algorithm, for the delineation of the P waves, which works well even in such cases. The algorithm basically consists of Pole-zero modeling of the discrete cosine transformed ECG. The resulting Pole-zero filter is then decomposed into a set of unique partial fractions (PF), with each PF representing a sub-component or a fractional component (FC) of the ECG. A Pole Angle template matching procedure is used to identify the PFs of the QRS and T waves, and then their corresponding FCs are subtracted from the ECG to leave the P wave as the residue. >

Jacek Piskorowski - One of the best experts on this subject based on the ideXlab platform.

  • MMAR - Time-varying FIR notch filter implementation using Raspberry Pi
    2015 20th International Conference on Methods and Models in Automation and Robotics (MMAR), 2015
    Co-Authors: Slawomir Kocon, Jacek Piskorowski
    Abstract:

    In this paper a hardware implementation of the finite impulse response narrow band-stop time-varying filter based on the infinite impulse prototype filter is proposed. The notch filter is used for removing power-line interferences from biomedical source, i.e. ECG signal. In order to suppress the transient state of the proposed filter, the Pole radius and the Pole Angle of the prototype filter are temporarily varied in time. The proposed filters are tested using sinusoidal and ECG signals. The algorithm for computing the filter coefficients is presented. Computer simulations, and performance indexes demonstrate that the proposed filter possesses better properties than traditional timeinvariant notch filter. Moreover, the hardware implementation of the presented filter using Raspberry Pi platform has been presented.

  • Time-varying FIR notch filter implementation using Raspberry Pi
    2015 20th International Conference on Methods and Models in Automation and Robotics (MMAR), 2015
    Co-Authors: Sławomir Kocoń, Jacek Piskorowski
    Abstract:

    In this paper a hardware implementation of the finite impulse response narrow band-stop time-varying filter based on the infinite impulse prototype filter is proposed. The notch filter is used for removing power-line interferences from biomedical source, i.e. ECG signal. In order to suppress the transient state of the proposed filter, the Pole radius and the Pole Angle of the prototype filter are temporarily varied in time. The proposed filters are tested using sinusoidal and ECG signals. The algorithm for computing the filter coefficients is presented. Computer simulations, and performance indexes demonstrate that the proposed filter possesses better properties than traditional time-invariant notch filter. Moreover, the hardware implementation of the presented filter using Raspberry Pi platform has been presented.

Jung-pyo Hong - One of the best experts on this subject based on the ideXlab platform.

  • Design of Multi-layer IPMSM using Ferrite PM Considering Mechanical and Electrical Characteristics
    2019 IEEE Energy Conversion Congress and Exposition (ECCE), 2019
    Co-Authors: Young-hoon Jung, Jung-pyo Hong
    Abstract:

    This paper proposes the design method of the multi-layer IPMSM using ferrite PM considering mechanical and electrical characteristics. The various design methods of the multi-layer IPMSM have been presented, but the irreversible demagnetization is not considered during the design of the motor. In this paper, the multi-layer IPMSM is designed considering the irreversible demagnetization during the design. Because the occurrence of the local irreversible demagnetization can be confirmed by finite element analysis (FEA), the design of the motor proceeds using the FEA. The PM shape, the ratio of the PM thickness and core thickness, the number of PM layers, the Pole-Angle, the number of bridges, and the thickness of bridges are determined considering the mechanical and electrical characteristics. Improved design to expand the satisfactory area of the target power and reduce the irreversible demagnetization is performed.

  • Effects of rotor Pole Angle on torque characteristics of a limited-Angle torque motor
    2017 IEEE International Electric Machines and Drives Conference (IEMDC), 2017
    Co-Authors: Soon-o Kwon, Seung-gyo Jang, Jung-pyo Hong
    Abstract:

    This paper presents a reluctance-type limited-Angle torque motor (LATM), which is used for actuator or arming device in the aerospace industry, and its electromagnetic (EM) characteristics were examined with respect to changes in the rotor Pole Angle and the rotational position of the LATM. Among the various shape design parameters of the LATM, changes in the rotor Pole Angle theoretically influence the cross-sectional area of the air-gap, thereby influencing torque generation. A three-dimensional EM finite-element analysis (FEA) was used to evaluate the irregular distribution of the magnetic flux inside the LATM. Finally, an LATM model having a Pole Angle at which the average and maximum torque become the largest and the torque ripple becomes the smallest (20% or lower) was designed.

  • Initial design using space harmonic analysis methods in permanent magnet synchronous machines
    Digests of the 2010 14th Biennial IEEE Conference on Electromagnetic Field Computation, 2010
    Co-Authors: Soon-o Kwon, Jung-pyo Hong
    Abstract:

    The influence of various design parameters on the back electromotive force (back-EMF) and its total harmonic distortion (THD) in surface type permanent magnet synchronous machine (SPMSM) is investigated in this paper. The ratio of Pole Angle, slot opening, Pole number and size of SPMSM are chosen as the design parameters. By using analytical method based on the space harmonic analysis, the variation of back-EMF and back-EMF THD are estimated and mapped according to the variety of these design parameters. And parameter results will be selected by range for meeting the characteristic requirements of SPMSM. The study results of this paper will be helpful to the PMSM design with back-EMF and THD optimization. The results will be verified by the finite element analysis.

  • IAS - A Study on the Acoustic Noise Reduction of Interior Permanent Magnet Motor with Concentrated Winding
    2008 IEEE Industry Applications Society Annual Meeting, 2008
    Co-Authors: Jung-pyo Hong
    Abstract:

    This paper deals with a study on the acoustic noise reduction according to the change of the Pole Angle in interior permanent magnet (IPM) motor with concentrated winding. This research is divided into 3 steps. Firstly, noise sources, such as resonant frequencies of stator and harmonic component of magnetic forces, are analyzed by the simulation and experimental results, respectively. Secondly, design of experiment (DOE) and optimal design using response surface methodology (RSM) are utilized to reduce the harmonic component of magnetic forces at a stator tooth compared with prototype. Objective function in the DOE and the optimal design is that the reduction of the summation of harmonic magnitude of normal force at a stator tooth. Finally, the reduction degree of the acoustic noise is compared by experimental results under the rated operating condition.

  • A Study on the Acoustic Noise Reduction of Interior Permanent Magnet Motor with Concentrated Winding
    2008 IEEE Industry Applications Society Annual Meeting, 2008
    Co-Authors: Jung-pyo Hong
    Abstract:

    This paper deals with a study on the acoustic noise reduction according to the change of the Pole Angle in interior permanent magnet (IPM) motor with concentrated winding. This research is divided into 3 steps. Firstly, noise sources, such as resonant frequencies of stator and harmonic component of magnetic forces, are analyzed by the simulation and experimental results, respectively. Secondly, design of experiment (DOE) and optimal design using response surface methodology (RSM) are utilized to reduce the harmonic component of magnetic forces at a stator tooth compared with prototype. Objective function in the DOE and the optimal design is that the reduction of the summation of harmonic magnitude of normal force at a stator tooth. Finally, the reduction degree of the acoustic noise is compared by experimental results under the rated operating condition.