The Flow and Pressure Relationships in Different Tubes Commonly Used for Semi-occluded Vocal Tract Exercises

This experimental study investigated the back pressure (pback) versus flow (U) relationship for 10 different tubes commonly used for semi-occluded vocal tract exercises (SOVTE), i.e., 8 straws of different lengths and diameters, a resonance tube and a silicone tube similar to a Lax Vox tube. All tubes were assessed with the free end in air. The resonance tube and silicone tube were further assessed with the free end under water at the depths from 1 to 7 cm in steps of 1 cm. The results showed that relative changes in the diameter of straws affect pback considerably more compared to the same amount of relative change in length. Additionally, once tubes are submerged into water, pback needs to overcome the pressure generated by the water depth before flow can start. Under this condition, only a small increase in pback was observed as the flow was increased. Therefore, the wider tubes submerged into water produced an almost constant pback determined by the water depth, while the thinner straws in air produced relatively large changes to pback as flow was changed. These differences may be taken advantage of when customizing exercises for different users and diagnoses and optimizing the therapy outcome

Computer methods for voice analysis

This thesis consists of five articles and a summary. Thethesis deals with methods for measuring properties of thevoice. The methods are all computer-based, but utilisedifferent approaches for measuring different aspects of thevoice. Paper I introduces the Visual Sort and Rate (VSR) method forperceptual rating of voice quality. The method is based on theVisual Analogue Scale (VAS), but simultaneously shows allstimuli as icons along the VAS on the computer screen. As thelistener places similar-sounding stimuli close to each otherduring the rating process, comparing stimuli becomeseasier. Paper II introduces the correlogram. Fundamental frequencyF0 sometimes cannot be strictly defined, particularly forperturbed voice signals. The method displays multipleconsecutive correlation functions in a grey scale image. Thus,the correlogram avoids selecting a single F0 value. Rather itpresents an unbiased image of periodicity, allowing theinvestigator to select among several candidates, ifappropriate. PaperIII introduces a method for detection of phonation tobe utilised in voice accumulators. The method uses twomicrophones attached near the subject\u92s ears. Phase andamplitude relations of the microphone signals are used to forma phonation detector. The output of the method can be used tomeasure phonation time, speaking time and fundamental frequencyof the subject, as well as sound pressure level of both thesubject\u92s voicing and the ambient sounds. Paper IV introduces a method for Fourier analysis ofhigh-speed laryngoscopic imaging. The data from the consecutiveimages are re-arranged to form time-series that reflect thetime-variation of light intensity in each pixel. Each of thesetime series is then analysed by means of Fouriertransformation, such that a spectrum for each pixel isobtained. Several ways of displaying these spectra aredemonstrated. Paper V examines a test set-up for simultaneous recording ofairflow, intra-oral pressure, electro-glottography, audio andhigh-speed imaging. Data are analysed with particular focus onsynchronisation between glottal area and inverse filteredairflow. Several methodological aspects are also examined, suchas the difficulties in synchronising high-speed imaging datawith the other signals.QC 2010060

Computer methods for voice analysis

This thesis consists of five articles and a summary. Thethesis deals with methods for measuring properties of thevoice. The methods are all computer-based, but utilisedifferent approaches for measuring different aspects of thevoice. Paper I introduces the Visual Sort and Rate (VSR) method forperceptual rating of voice quality. The method is based on theVisual Analogue Scale (VAS), but simultaneously shows allstimuli as icons along the VAS on the computer screen. As thelistener places similar-sounding stimuli close to each otherduring the rating process, comparing stimuli becomeseasier. Paper II introduces the correlogram. Fundamental frequencyF0 sometimes cannot be strictly defined, particularly forperturbed voice signals. The method displays multipleconsecutive correlation functions in a grey scale image. Thus,the correlogram avoids selecting a single F0 value. Rather itpresents an unbiased image of periodicity, allowing theinvestigator to select among several candidates, ifappropriate. PaperIII introduces a method for detection of phonation tobe utilised in voice accumulators. The method uses twomicrophones attached near the subject\u92s ears. Phase andamplitude relations of the microphone signals are used to forma phonation detector. The output of the method can be used tomeasure phonation time, speaking time and fundamental frequencyof the subject, as well as sound pressure level of both thesubject\u92s voicing and the ambient sounds. Paper IV introduces a method for Fourier analysis ofhigh-speed laryngoscopic imaging. The data from the consecutiveimages are re-arranged to form time-series that reflect thetime-variation of light intensity in each pixel. Each of thesetime series is then analysed by means of Fouriertransformation, such that a spectrum for each pixel isobtained. Several ways of displaying these spectra aredemonstrated. Paper V examines a test set-up for simultaneous recording ofairflow, intra-oral pressure, electro-glottography, audio andhigh-speed imaging. Data are analysed with particular focus onsynchronisation between glottal area and inverse filteredairflow. Several methodological aspects are also examined, suchas the difficulties in synchronising high-speed imaging datawith the other signals.QC 2010060

Enhancements to the Visual Analogue Scale,

Three methods for perceptual rating of audio stimuli were compared. The Visual Analogue Scale, VAS, was implemented as two computer programs and compared to the VAS on paper. The first program is a straight-forward implementation, the second program introduces the Visual Sort and Rate method, VSR. VSR allows the subject to compare stimuli of similar rating to each other, thus making the ordering of the stimuli easier. The three methods were compared by using a series of stimuli having different spectral tilt. Results show that the VSR method gives better reliability in the subjects' ratings. Average correlation coefficients increased from 0.93 for VAS on paper, to 0.95 for Computer based VAS and 0.98 for the VSR method

A method for extracting vibrato parameters applied to violin performance

A method is presented which semi-automatically extracts the fundamental frequency and displays as continuous signals vibrato rate, vibrato extent and sound level. The method is tested on specially made recordings of violin music with piano accompaniment, using a small microphone mounted directly on the violin. The fundamental frequency was successfully extracted by means of a waveform correlation program. Likewise, vibrato rate and extent were extracted separately for each tone from the fundamental frequency signal after elimination of its DC component. The results seem promising, offering the opportunity of visual examination and measurement of changes in vibrato characteristics during performances of entire pieces of music. QC 20180907</p

A method for extracting vibrato parameters applied to violin performance

A method is presented which semi-automatically extracts the fundamental frequency and displays as continuous signals vibrato rate, vibrato extent and sound level. The method is tested on specially made recordings of violin music with piano accompaniment, using a small microphone mounted directly on the violin. The fundamental frequency was successfully extracted by means of a waveform correlation program. Likewise, vibrato rate and extent were extracted separately for each tone from the fundamental frequency signal after elimination of its DC component. The results seem promising, offering the opportunity of visual examination and measurement of changes in vibrato characteristics during performances of entire pieces of music. QC 20180907</p

http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-20457 Child Voice and Noise: A Pilot Study of Noise in Day Cares and the Effects on 10 Children&apos;s Voice Quality According to Perceptual Evaluation

The purpose of this investigation was to study children&apos;s exposure to background noise at the ears during a normal day at the day care center and also to relate this to a perceptual evaluation of voice quality. Ten children, from three day care centers, with no history of hearing and speech problems or frequent infections were selected as subjects. A binaural recording technique was used with two microphones placed on both sides of the subject&apos;s head, at equal distance from the mouth. A portable digital audio tape (DAT) recorder (Sony TCD-D 100, Stockholm, Sweden) was attached to the subject&apos;s waist. Three recordings were made for each child during the day. Each recording was calibrated and started with three repetitions of three sentences containing only sonorants. The recording technique allowed separate analyses of the background noise level and of the sound pressure level (SPL) of each subjects &apos; own voice. Results showed a mean background noise level for the three day care centers at 82.6 dBA Leq, ranging from 81.5 to 83.6 dBA Leq. Day care center no. 2 had the highest mean value and also the highest value at any separate recording session with a mean background noise level of 85.4 dBA Leq during the noontime recordings. Perceptual evaluation showed that the children attending this day care center also received higher value

Child Voice and Noise : A Pilot Study of Noise in Day Cares and the Effects on 10 Children's Voice Quality According to Perceptual Evaluation

The purpose of this investigation was to study children's exposure to background noise at the ears during a normal day at the day care center and also to relate this to a perceptual evaluation of voice quality. Ten children, from three day care centers, with no history of hearing and speech problems or frequent infections were selected as subjects. A binaural recording technique was used with two microphones placed on both sides of the subject's head, at equal distance from the mouth. A portable digital audio tape (DAT) recorder (Sony TCD-D 100, Stockholm, Sweden) was attached to the subject's waist. Three recordings were made for each child during the day. Each recording was calibrated and started with three repetitions of three sentences containing only sonorants. The recording technique allowed separate analyses of the background noise level and of the sound pressure level (SPL) of each subjects' own voice. Results showed a mean background noise level for the three day care centers at 82.6dBA Leq, ranging from 81.5 to 83.6dBA Leq. Day care center no. 2 had the highest mean value and also the highest value at any separate recording session with a mean background noise level of 85.4dBA Leq during the noontime recordings. Perceptual evaluation showed that the children attending this day care center also received higher values on the following voice characteristics: hoarseness, breathiness, and hyperfunction. Girls increased their loudness level during the day, whereas for boys no such change could be observed.  Original Publication:Anita McAllister, Svante Granqvist, Peta Sjölander and Johan Sundberg, Child Voice and Noise: A Pilot Study of Noise in Day Cares and the Effects on 10 Children's Voice Quality According to Perceptual Evaluation, 2009, Journal of Voice, (23), 5, 587-593.http://dx.doi.org/10.1016/j.jvoice.2007.10.017Copyright: Elsevier Science B.V. Amsterdamhttp://www.elsevier.com/BUG- Barn, utveckling, genu