{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,4]],"date-time":"2026-10-04T18:48:22Z","timestamp":1791139702874,"version":"4.1.0"},"reference-count":28,"publisher":"Acoustical Society of America (ASA)","issue":"2","content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2002,8,1]]},"abstract":"<jats:p>Normalized amplitude quotient (NAQ) is presented as a method to parametrize the glottal closing phase using two amplitude-domain measurements from waveforms estimated by inverse filtering. In this technique, the ratio between the amplitude of the ac flow and the negative peak amplitude of the flow derivative is first computed using the concept of equivalent rectangular pulse, a hypothetical signal located at the instant of the main excitation of the vocal tract. This ratio is then normalized with respect to the length of the fundamental period. Comparison between NAQ and its counterpart among the conventional time-domain parameters, the closing quotient, shows that the proposed parameter is more robust against distortion such as measurement noise that make the extraction of conventional time-based parameters of the glottal flow problematic. Experiments with breathy, normal, and pressed vowels indicate that NAQ is also able to separate the type of phonation effectively.<\/jats:p>","DOI":"10.1121\/1.1490365","type":"journal-article","created":{"date-parts":[[2002,10,1]],"date-time":"2002-10-01T19:32:46Z","timestamp":1033500766000},"page":"701-710","update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":207,"title":["Normalized amplitude quotient for parametrization of the glottal flow"],"prefix":"10.1121","volume":"112","author":[{"given":"Paavo","family":"Alku","sequence":"first","affiliation":[{"name":"Helsinki University of Technology, Laboratory of Acoustics and Audio Signal Processing, Box 3000, Fin-02015\u2009TKK, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tom","family":"B\u00e4ckstr\u00f6m","sequence":"additional","affiliation":[{"name":"Helsinki University of Technology, Laboratory of Acoustics and Audio Signal Processing, Box 3000, Fin-02015\u2009TKK, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erkki","family":"Vilkman","sequence":"additional","affiliation":[{"name":"University of Oulu, Department of Otolaryngology and Phoniatrics, Oulu, Finland"},{"name":"Helsinki University Central Hospital, Box 220, Fin-00029\u2009HUS, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"231","published-online":{"date-parts":[[2002,7,31]]},"reference":[{"key":"2023071408175207500_alk97","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1016\/S0167-6393(97)00020-4","article-title":"Parabolic spectral parameter\u2014A new method for quantification of the glottal flow","volume":"22","year":"1997","journal-title":"Speech Commun."},{"key":"2023071408175207500_alk94"},{"key":"2023071408175207500_alk6a","doi-asserted-by":"crossref","first-page":"240","DOI":"10.1159\/000266415","article-title":"A comparison of glottal voice source quantification parameters in breathy, normal, and pressed phonation of female and male speakers","volume":"48","year":"1996","journal-title":"Folia Phoniatr Logop"},{"key":"2023071408175207500_alk6b","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1016\/0167-6393(95)00040-2","article-title":"Amplitude domain quotient for characterization of the glottal volume velocity waveform estimated by inverse filtering","volume":"18","year":"1996","journal-title":"Speech Commun."},{"key":"2023071408175207500_car86"},{"key":"2023071408175207500_car89"},{"key":"2023071408175207500_chi91","doi-asserted-by":"crossref","first-page":"2394","DOI":"10.1121\/1.402044","article-title":"Vocal quality factors: Analysis, synthesis, and perception","volume":"90","year":"1991","journal-title":"J. Acoust. Soc. Am."},{"key":"2023071408175207500_dro92","doi-asserted-by":"crossref","first-page":"44","DOI":"10.1016\/S0892-1997(05)80008-6","article-title":"Glottal airflow and electroglottographic measures of vocal function at multiple intensities","volume":"6","year":"1992","journal-title":"J. Voice"},{"key":"2023071408175207500_elj91","doi-asserted-by":"crossref","first-page":"411","DOI":"10.1109\/78.80824","article-title":"Discrete all-pole modeling","volume":"39","year":"1991","journal-title":"IEEE Trans. Signal Process."},{"key":"2023071408175207500_fan93","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1016\/0167-6393(93)90055-P","article-title":"Some problems in voice source analysis","volume":"13","year":"1993","journal-title":"Speech Commun."},{"key":"2023071408175207500_fan95"},{"key":"2023071408175207500_fan97","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1016\/S0167-6393(97)00017-4","article-title":"The voice source in connected speech","volume":"22","year":"1997","journal-title":"Speech Commun."},{"key":"2023071408175207500_fan94"},{"key":"2023071408175207500_fan85"},{"key":"2023071408175207500_fan88"},{"key":"2023071408175207500_fro01","doi-asserted-by":"crossref","first-page":"479","DOI":"10.1121\/1.1379076","article-title":"SIM\u2014Simultaneous inverse filtering and matching of a glottal flow model for acoustic speech signals","volume":"110","year":"2001","journal-title":"J. Acoust. Soc. Am."},{"key":"2023071408175207500_her92","doi-asserted-by":"crossref","first-page":"224","DOI":"10.1016\/S0892-1997(05)80147-X","article-title":"Physiological correlates of the inverse filtered flow waveform","volume":"6","year":"1992","journal-title":"J. Voice"},{"key":"2023071408175207500_hol88","doi-asserted-by":"crossref","first-page":"511","DOI":"10.1121\/1.396829","article-title":"Glottal airflow and transglottal air pressure measurements for male and female speakers in soft, normal, and loud voice","volume":"84","year":"1988","journal-title":"J. Acoust. Soc. Am."},{"key":"2023071408175207500_how92","doi-asserted-by":"crossref","first-page":"1697","DOI":"10.1121\/1.402449","article-title":"Acoustic analysis and perception of vowels in children\u2019s and teenagers\u2019 stuttered speech","volume":"91","year":"1992","journal-title":"J. Acoust. Soc. Am."},{"key":"2023071408175207500_mon77","doi-asserted-by":"crossref","first-page":"981","DOI":"10.1121\/1.381593","article-title":"Study of variations in the male and female glottal wave","volume":"62","year":"1977","journal-title":"J. Acoust. Soc. Am."},{"key":"2023071408175207500_moo82"},{"key":"2023071408175207500_rot73","doi-asserted-by":"crossref","first-page":"1632","DOI":"10.1121\/1.1913513","article-title":"A new inverse-filtering technique for deriving the glottal air flow waveform during voicing","volume":"53","year":"1973","journal-title":"J. Acoust. Soc. Am."},{"key":"2023071408175207500_str92","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1016\/0167-6393(92)90011-U","article-title":"On the relation between voice source parameters and prosodic features in connected speech","volume":"11","year":"1992","journal-title":"Speech Commun."},{"key":"2023071408175207500_sul96","doi-asserted-by":"crossref","first-page":"3360","DOI":"10.1121\/1.416977","article-title":"Glottal volume velocity waveform characteristics in subjects with and without vocal training, related to gender, sound intensity, fundamental frequency, and age","volume":"100","year":"1996","journal-title":"J. Acoust. Soc. Am."},{"key":"2023071408175207500_sun99","doi-asserted-by":"crossref","first-page":"1965","DOI":"10.1121\/1.426731","article-title":"Effects of subglottal pressure variation on professional baritone singers\u2019 voice sources","volume":"105","year":"1999","journal-title":"J. Acoust. Soc. Am."},{"key":"2023071408175207500_sun93","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1016\/S0892-1997(05)80108-0","article-title":"Phonatory control in male singing: A study of the effects of subglottal pressure, fundamental frequency, and mode of phonation on the voice source","volume":"7","year":"1993","journal-title":"J. Voice"},{"key":"2023071408175207500_wil62"},{"key":"2023071408175207500_won79","doi-asserted-by":"crossref","first-page":"350","DOI":"10.1109\/TASSP.1979.1163260","article-title":"Least-squares glottal inverse filtering from acoustic speech waveforms","volume":"27","year":"1979","journal-title":"IEEE Trans. Acoust., Speech, Signal Process."}],"container-title":["The Journal of the Acoustical Society of America"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pubs.aip.org\/asa\/jasa\/article-pdf\/112\/2\/701\/8090982\/701_1_online.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/pubs.aip.org\/asa\/jasa\/article-pdf\/112\/2\/701\/8090982\/701_1_online.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,7,14]],"date-time":"2023-07-14T08:42:43Z","timestamp":1689324163000},"score":1,"resource":{"primary":{"URL":"https:\/\/pubs.aip.org\/jasa\/article\/112\/2\/701\/546599\/Normalized-amplitude-quotient-for-parametrization"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2002,7,31]]},"references-count":28,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2002,8,1]]}},"URL":"https:\/\/doi.org\/10.1121\/1.1490365","relation":{},"ISSN":["0001-4966","1520-8524"],"issn-type":[{"value":"0001-4966","type":"print"},{"value":"1520-8524","type":"electronic"}],"subject":[],"published-other":{"date-parts":[[2002,8]]},"published":{"date-parts":[[2002,7,31]]}}}