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Toshimitsu Shinohara - One of the best experts on this subject based on the ideXlab platform.

  • validation of a new system of tracheal Sound Analysis for the diagnosis of sleep apnea hypopnea syndrome
    Sleep, 2004
    Co-Authors: Hiroshi Nakano, Makito Hayashi, Etsuko Ohshima, Nahoko Nishikata, Toshimitsu Shinohara
    Abstract:

    STUDY OBJECTIVES: To evaluate the validity of a novel method of using tracheal Sound Analysis for the diagnosis of sleep apnea-hypopnea syndrome. DESIGN: Retrospective Analysis in consecutive patients. SETTING: A sleep clinic in a general hospital. PATIENTS: A total of 383 patients who were referred for suspected sleep apnea-hypopnea syndrome and underwent diagnostic polysomnography with sufficient quality. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Ordinary polysomnography with simultaneous tracheal Sound recording was performed. The apnea-hypopnea index (AHI) was calculated as the number of apnea and hypopnea events per hour of sleep. Tracheal Sounds were digitized and recorded as power spectra. An automated computer program detected transient falls (TS-dip) in the time series of moving average of the logarithmic power of tracheal Sound. We defined the tracheal Sound-respiratory disturbance index (TS-RDI) as the number of TS-dips per hour of examination. We also calculated the oxygen desaturation index (the number of SaO2 dips of at least 4% per hour of examination). The TS-RDI highly correlated with AHI (r = 0.93). The mean (+/- SD) difference between the TS-RDI and AHI was -8.4 +/- 10.4. The diagnostic sensitivity and specificity of the TS-RDI when the same cutoff value was used as for AHI were 93% and 67% for the AHI cutoff value of 5 and 79% and 95% for the AHI cutoff value of 15. The agreement between the TS-RDI and AHI was better than that between the oxygen desaturation index and AHI. CONCLUSIONS: The fully automated tracheal Sound Analysis demonstrated a relatively high performance in the diagnosis of sleep apnea-hypopnea syndrome. We think that this method is useful for the portable monitoring of sleep apnea-hypopnea syndrome.

Hiroshi Nakano - One of the best experts on this subject based on the ideXlab platform.

  • lung Sound Analysis in a patient with vocal cord dysfunction and bronchial asthma
    Journal of Asthma, 2012
    Co-Authors: Yuko Amimoto, Hiroshi Nakano, Natsuko Masumoto, Akiko Ishimatsu, Yohei Arakaki, Naohiko Taba, Yoko Murakami, Chikako Motomura, Hiroshi Odajima
    Abstract:

    Objective. Vocal cord dysfunction (VCD) is a condition characterized by adduction of the vocal cords, resulting in narrowing or even closure of the glottis during inspiration. This can cause wheezing that originates at the site of narrowing. Some patients have both VCD and asthma. In such cases, an acute episode of VCD can be difficult to differentiate from that of asthma. We tested the usefulness of lung Sound Analysis (LSA) in such a condition. Methods. We performed an LSA in a patient with asthma and coexisting VCD diagnosed using laryngoscopy. Results and conclusion. The LSA during an acute VCD episode revealed monophonic continuous adventitious Sounds that were distributed symmetrically over both lung fields. The time domain Analysis revealed that the adventitious Sounds originated in the neck. These LSA findings clearly indicated that the acute episode was not due to asthma but due to VCD. This case illustrates that the LSA may be a useful tool to differentiate between an acute episode of asthma and...

  • validation of a new system of tracheal Sound Analysis for the diagnosis of sleep apnea hypopnea syndrome
    Sleep, 2004
    Co-Authors: Hiroshi Nakano, Makito Hayashi, Etsuko Ohshima, Nahoko Nishikata, Toshimitsu Shinohara
    Abstract:

    STUDY OBJECTIVES: To evaluate the validity of a novel method of using tracheal Sound Analysis for the diagnosis of sleep apnea-hypopnea syndrome. DESIGN: Retrospective Analysis in consecutive patients. SETTING: A sleep clinic in a general hospital. PATIENTS: A total of 383 patients who were referred for suspected sleep apnea-hypopnea syndrome and underwent diagnostic polysomnography with sufficient quality. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Ordinary polysomnography with simultaneous tracheal Sound recording was performed. The apnea-hypopnea index (AHI) was calculated as the number of apnea and hypopnea events per hour of sleep. Tracheal Sounds were digitized and recorded as power spectra. An automated computer program detected transient falls (TS-dip) in the time series of moving average of the logarithmic power of tracheal Sound. We defined the tracheal Sound-respiratory disturbance index (TS-RDI) as the number of TS-dips per hour of examination. We also calculated the oxygen desaturation index (the number of SaO2 dips of at least 4% per hour of examination). The TS-RDI highly correlated with AHI (r = 0.93). The mean (+/- SD) difference between the TS-RDI and AHI was -8.4 +/- 10.4. The diagnostic sensitivity and specificity of the TS-RDI when the same cutoff value was used as for AHI were 93% and 67% for the AHI cutoff value of 5 and 79% and 95% for the AHI cutoff value of 15. The agreement between the TS-RDI and AHI was better than that between the oxygen desaturation index and AHI. CONCLUSIONS: The fully automated tracheal Sound Analysis demonstrated a relatively high performance in the diagnosis of sleep apnea-hypopnea syndrome. We think that this method is useful for the portable monitoring of sleep apnea-hypopnea syndrome.

Xavier Rodet - One of the best experts on this subject based on the ideXlab platform.

  • Automatic Adaptation of the Time-Frequency Resolution for Sound Analysis and Re-Synthesis
    IEEE Transactions on Audio Speech and Language Processing, 2013
    Co-Authors: Marco Liuni, Axel Roebel, Ewa Matusiak, Marco Romito, Xavier Rodet
    Abstract:

    We present an algorithm for Sound Analysis and re-synthesis with local automatic adaptation of time-frequency resolution. The reconstruction formula we propose is highly efficient, and gives a good approximation of the original signal from analyses with different time-varying resolutions within complementary frequency bands: this is a typical case where perfect reconstruction cannot in general be achieved with fast algorithms, which provides an error to be minimized. We provide a theoretical upper bound for the reconstruction error of our method, and an example of automatic adaptive Analysis and re- synthesis of a music Sound.

  • Sound Analysis, processing and synthesis tools for music research and production
    2000
    Co-Authors: Xavier Rodet
    Abstract:

    Sound Analysis, processing and synthesis tools for music research and production

  • spectral envelope estimation and representation for Sound Analysis synthesis
    International Computer Music Conference, 1999
    Co-Authors: Diemo Schwartz, Xavier Rodet
    Abstract:

    Spectral envelopes are very useful in Sound Analysis and synthesis because of their connection with production and perception models, and their ability to capture and to manipulate important properties of Sound using easily understandable “musical” parameters. It is not easy, however, to estimate and represent them well, as several requirements must be fulfilled. We discuss the strengths and weaknesses of the estimation methods LPC, cepstrum, and discrete cepstrum, and evaluate the representations filter coefficients, sampled, break-point functions, splines, and formants. The proposed high-level approach to spectral envelope handling is followed in software developed at IRCAM, which makes some important applications of spectral envelopes in the domain of additive Analysis–synthesis possible.

  • ICMC - Spectral Envelope Estimation and Representation for Sound Analysis-Synthesis
    1999
    Co-Authors: Diemo Schwartz, Xavier Rodet
    Abstract:

    Spectral envelopes are very useful in Sound Analysis and synthesis because of their connection with production and perception models, and their ability to capture and to manipulate important properties of Sound using easily understandable “musical” parameters. It is not easy, however, to estimate and represent them well, as several requirements must be fulfilled. We discuss the strengths and weaknesses of the estimation methods LPC, cepstrum, and discrete cepstrum, and evaluate the representations filter coefficients, sampled, break-point functions, splines, and formants. The proposed high-level approach to spectral envelope handling is followed in software developed at IRCAM, which makes some important applications of spectral envelopes in the domain of additive Analysis–synthesis possible.

  • New Possibilities in Sound Analysis and Synthesis
    1995
    Co-Authors: Xavier Rodet, Philippe Depalle, Guillermo Garcia
    Abstract:

    In this presentation we exemplify the emergence of new possibilities in Sound Analysis and synthesis with three novel developments that have been done in the Analysis/Synthesis team at IRCAM. These examples address three main activities in our domain, and have reached a large public making or simply listening to music. The first example concerns synthesis using physical models. We have determined the behavior of a class of models, in terms of stability, oscillation, periodicity, and finally chaos, leading to a better control of these models in truly innovative musical applications. The second example concerns additive synthesis essentially based on the Analysis of natural Sounds. We have developed a new additive method based on spectral envelopes and inverse Fast Fourier Transform, which we name FFT-1 and which provides a solution to the different difficulties of the classical method. Commercial applications are announced for this year, for professional users and soon for a larger public. The last example is an original work on the recreation of a castrato voice by the means of Sound Analysis, processing andsynthesis. It has been done for the Soundtrack for a film and a CD about Farinelli, the famous castrato of the eighteenth century. The CD and the film have reached millions of people all around the world.

J. Rejec - One of the best experts on this subject based on the ideXlab platform.

  • An approach to fault diagnosis of vacuum cleaner motors based on Sound Analysis
    Mechanical Systems and Signal Processing, 2005
    Co-Authors: U. Benko, J. Petrovčič, Đ. Juričić, J. Tavčar, J. Rejec
    Abstract:

    This paper addresses the problem of the detailed quality end-test of vacuum cleaner motors at the end of the manufacturing cycle. For the prototyping purposes a test rig has been constructed and is presented in short. The diagnostic system built hereto takes advantage of vibration, Sound and commutation Analysis as well as parity relation checks. The paper focuses on the Sound Analysis module and provides two main contributions. First, an Analysis of Sound sources is performed and a set of appropriate features is suggested. Second, efficient signal processing algorithms are developed in order to detect and localise bearing faults, defects in fan impeller, improper brush–commutator contacts and rubbing of rotating surfaces. A thorough laboratory study shows that the underlying diagnostic modules provide accurate diagnosis, high sensitivity with respect to faults, and good diagnostic resolution.

  • Fault diagnosis of a vacuum cleaner motor by means of Sound Analysis
    Journal of Sound and Vibration, 2004
    Co-Authors: U. Benko, J. Petrovčič, Đ. Juričić, J. Tavčar, J. Rejec, A. Stefanovska
    Abstract:

    Achieving high quality standards and 100% defect-free deliverables is becoming a trend among manufacturers of household appliances. In that respect, thorough and reliable end-tests represent an important step towards this goal. This paper deals with the design of end-test procedures for vacuum cleaner motors based on Sound Analysis. It is well known that Sound carries important information about the condition of contact surfaces in rotating parts. The paper aims first to provide a thorough Analysis of Sound sources within the motor. Second, by using simple yet effective signal processing tools, it is shown that with Sound Analysis alone it is possible to clearly distinguish fault-free motors from those with mechanical faults. Moreover, the proposed algorithm exhibits a certain isolation capability, i.e., it is able to distinguish three clusters of faults. Finally, a summary of experimental results obtained on a sample of 75 motors is provided

Makito Hayashi - One of the best experts on this subject based on the ideXlab platform.

  • validation of a new system of tracheal Sound Analysis for the diagnosis of sleep apnea hypopnea syndrome
    Sleep, 2004
    Co-Authors: Hiroshi Nakano, Makito Hayashi, Etsuko Ohshima, Nahoko Nishikata, Toshimitsu Shinohara
    Abstract:

    STUDY OBJECTIVES: To evaluate the validity of a novel method of using tracheal Sound Analysis for the diagnosis of sleep apnea-hypopnea syndrome. DESIGN: Retrospective Analysis in consecutive patients. SETTING: A sleep clinic in a general hospital. PATIENTS: A total of 383 patients who were referred for suspected sleep apnea-hypopnea syndrome and underwent diagnostic polysomnography with sufficient quality. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Ordinary polysomnography with simultaneous tracheal Sound recording was performed. The apnea-hypopnea index (AHI) was calculated as the number of apnea and hypopnea events per hour of sleep. Tracheal Sounds were digitized and recorded as power spectra. An automated computer program detected transient falls (TS-dip) in the time series of moving average of the logarithmic power of tracheal Sound. We defined the tracheal Sound-respiratory disturbance index (TS-RDI) as the number of TS-dips per hour of examination. We also calculated the oxygen desaturation index (the number of SaO2 dips of at least 4% per hour of examination). The TS-RDI highly correlated with AHI (r = 0.93). The mean (+/- SD) difference between the TS-RDI and AHI was -8.4 +/- 10.4. The diagnostic sensitivity and specificity of the TS-RDI when the same cutoff value was used as for AHI were 93% and 67% for the AHI cutoff value of 5 and 79% and 95% for the AHI cutoff value of 15. The agreement between the TS-RDI and AHI was better than that between the oxygen desaturation index and AHI. CONCLUSIONS: The fully automated tracheal Sound Analysis demonstrated a relatively high performance in the diagnosis of sleep apnea-hypopnea syndrome. We think that this method is useful for the portable monitoring of sleep apnea-hypopnea syndrome.