Objective: ElectrodeNet, a deep-learning based sound coding strategy for the cochlear implant (CI... more Objective: ElectrodeNet, a deep-learning based sound coding strategy for the cochlear implant (CI), is proposed in this study. The performance between ElectrodeNet and the advanced combination encoder (ACE) coding strategy in speech intelligibility is compared. Methods: ElectrodeNet emulates the ACE strategy and replaces the conventional envelope detection using various forms of artificial neural networks. Network models of deep neural network (DNN), convolutional neural network (CNN), and long short-term memory (LSTM) were trained using the fast Fourier transformed clean speech and the corresponding electrode stimulation patterns. Objective speech intelligibility was estimated for ElectrodeNets for the factors of loss function, network architecture, language, and noise type. Subjective listening tests for vocoded Mandarin speech were conducted with 40 normal-hearing listeners. Results: DNN, CNN, and LSTM based ElectrodeNets exhibited strong correlations with the ACE strategy in sho...
2001 Conference Proceedings of the 23rd Annual International Conference of the IEEE Engineering in Medicine and Biology Society
ABSTRACT People with speech impairments are likely to also have varied movement disorders which r... more ABSTRACT People with speech impairments are likely to also have varied movement disorders which result in the inability to use existing voice telephone facility. The aim of this research is to extend the current augmentative and alternative communication (AAC) system to wireless telecommunication service, for speech-impaired subjects. A pocket personal computer (PPC) with a Global System for Mobile Communications (GSM) module is adopted herein. The touch screen of PPC with designed graphics icon can be used as large buttons to activate the high-fidelity sound that is in turns sent to the GSM module for "talking" through the phone. An AAC layout editor is used to link the pre-recorded sound to the graphics icon and to compile the icon-based graphics for each individual. In addition, levels of dynamic linkages, including script-based, category of use, semantic linkage, and frequency of use are implemented for assisting the speech impairment user to retrieve these pre-stored conversational items which can speed up the communication rate.
The purpose of this research was to add a speech enhancement process that could further improve s... more The purpose of this research was to add a speech enhancement process that could further improve speech intelligibility and the performance of automatic scene classification and automatching noise reduction system after the application of the adaptive directional microphone strategy. The speech enhancement system is divided into two parts: one is the noise-estimation strategy and the other the speech-estimation function. Noise-estimation algorithms used in the research are: minimum statistics (MS), minima-controlled recursive averaging (MCRA),improved(IMCRA), MCRA-Loizou (MCRA-L), constrained variance spectral smoothing (CVS), forward-backward MCRA(MCRA-FB);speech-estimation function: Wiener filter, maximum-likelihood (ML), log-spectral amplitude (LSA), maximum a posteriori amplitude (MAPA).In this research, The MATLAB program was first used to simulate the speech enhancement system to evaluate the quality of output speech signal under different signal-to-noise ratio (SNR) conditions...
Journal of Medical and Biological Engineering, 2008
Eye-writing herein introduced is a novel language communication method wherein the eyes fill the ... more Eye-writing herein introduced is a novel language communication method wherein the eyes fill the role of a writing organ. An eye-writing system detects the traces of eye movements and determines their corresponding symbols by pattern recognition. In this study, we measured the eye movements by electro-oculograophy (EOG). The electrical potential difference measured between the skins above and below the eyes reflected the eye movement in the vertical direction. That measured between tire skins to the left and to tire right of tire eyes reflected tire eye movement in tire horizontal direction. We evaluated the eye-writing system with a symbol set consisting of symbols of 10 Arabic numerals and 4 mathematic operators. Experiments on 11 voluntary human subjects shunned recognition rate ranging from 50% to 100% with different symbols. The recognition rate can be improved by several means to reads a desired level for practical applications. We conclude that eye-writing as a language commu...
The DIMX (Directions Into Velocities Articulator) model provides a computatienal and ncuroanatomi... more The DIMX (Directions Into Velocities Articulator) model provides a computatienal and ncuroanatomical account of speech acquisition and production; however, its prediction of speech perception and production for Mandarin is limited. The aim of this study is to modify the original DIMdL model to simulate both norrnal and speech disordered productions in Mandarin. The proposed version of the model provides aclditional functions of speech perception, tonal acquisition and diphthong production. Computer simulation of our modified DIVfiL model verifies its ability to simulate Mandarin tenal production in diphthong arid speech perception across vowels.
Evidence-Based Complementary and Alternative Medicine, 2018
Background. The Auto Manipulation Device for Acupuncture (AMDA) is designed for providing stable,... more Background. The Auto Manipulation Device for Acupuncture (AMDA) is designed for providing stable, quantified effects and higher frequency when doing lifting and thrusting manipulation. The purpose of this study is to investigate the safety of manipulation by AMDA in different frequency and duration in healthy rats. Methods. The study was divided into two parts: single intervention and once a day for a week. 12 rats and 15 rats were randomly allocated to different groups: Control (needle insertion only), AMDA (2Hz/10Mins), AMDA (2Hz/20Mins), AMDA (20Hz/10Mins), and AMDA (20Hz/20Mins) for single and repeated interventions. Real-time physiological functions, laboratory data, and the bilateral muscle tissue of acupoint (ST 36) were obtained after the intervention. Results. We found neither real-time physiological functions nor laboratory data differences between control group and AMDA groups in both parts. In the muscle tissue samples, the slight damage had been observed in the AMDA gro...
Disability and rehabilitation. Assistive technology, Aug 7, 2015
The purpose of this study is to develop a tool to assist speech therapy and rehabilitation, which... more The purpose of this study is to develop a tool to assist speech therapy and rehabilitation, which focused on automatic scoring based on the comparison of the patient's speech with another normal speech on several aspects including pitch, vowel, voiced-unvoiced segments, strident fricative and sound intensity. The pitch estimation employed the use of cepstrum-based algorithm for its robustness; the vowel classification used multilayer perceptron (MLP) to classify vowel from pitch and formants; and the strident fricative detection was based on the major peak spectral intensity, location and the pitch existence in the segment. In order to evaluate the performance of the system, this study analyzed eight patient's speech recordings (four males, four females; 4-58-years-old), which had been recorded in previous study in cooperation with Taipei Veterans General Hospital and Taoyuan General Hospital. The experiment result on pitch algorithm showed that the cepstrum method had 5.3% ...
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference, 2014
Needle lifting and thrusting manipulation is one of common skills in acupuncture. However, there ... more Needle lifting and thrusting manipulation is one of common skills in acupuncture. However, there exists artificial error in frequency and amplitude due to individual difference when performing lifting and thrusting during acupuncture. For providing stable and quantified effects and higher frequency when doing lifting and thrusting manipulation, a well controlled device is needed. The aim of this article is to report the preliminary results of the development of Auto Manipulation Device for Acupuncture (AMDA) and characterization of its functional parameters. A tissue-simulating Agar gel phantom with 4.8%, 5.2%, and 5.4% concentrations was prepared and used for characterization of the AMDA. Tests of the linearity, reliability and safety of the AMDA were implemented with conditions of different drive voltages, frequencies, and simulated tissues. Our preliminary results have demonstrated the developed AMDA its plausibility in the clinical application of acupuncture.
ABSTRACT Eye-writing herein introduced is a novel language communication method wherein the eyes ... more ABSTRACT Eye-writing herein introduced is a novel language communication method wherein the eyes fill the role of a writing organ. An eye-writing system detects the traces of eye movements and determines their corresponding symbols by pattern recognition. In this study, we measured the eye movements by electro-oculograophy (EOG). The electrical potential difference measured between the skins above and below the eyes reflected the eye movement in the vertical direction. That measured between the skins to the left and to the right of the eyes reflected the eye movement in the horizontal direction. We evaluated the eye-writing system with a symbol set consisting of symbols of 10 Arabic numerals and 4 mathematic operators. Experiments on 11 voluntary human subjects showed recognition rate ranging from 50% to 100 % with different symbols. The recognition rate can be improved by several means to reach a desired level for practical applications. We conclude that eye-writing as a language communication method is feasible. This technology will be especially useful for severe amyotrophic lateral sclerosis (ALS) patients who have lost the oral-speaking and hand-writing abilities.
The Journal of the Acoustical Society of America, 2008
The main purpose of this study is to build a MRI-based 3D tongue atlas for research on tongue mor... more The main purpose of this study is to build a MRI-based 3D tongue atlas for research on tongue morphometrics and physiological modeling of normal and disordered speech production. In this study, MRI data of 8 subjects (4 males and 4 females) were chosen from an orally-based MRI database of 20 male and 20 female college students without speech disorders. Sixteen landmarks were defined and selected from the 3D reconstructed MRI tongue images based on the subjects. Thin-plate spline analysis (TPS) was used to build a 3D tongue atlas for male and female subjects, respectively. Sagittal sections of the original MRI data were used to evaluate the accuracy of image registration and reconstruction. The resulted 3D tongue atlas was used to study subject-to subject, subject-to-atlas, and male-to-female morphometric variation. Preliminary results show the major difference among female subjects before and after the TPS analysis is in the area of tongue dorsum that is close to the velum and epigl...
The Journal of the Acoustical Society of America, 1996
The main objective of this work is to obtain reliable and detailed anatomical information for dev... more The main objective of this work is to obtain reliable and detailed anatomical information for developing a quantitative 3-D tongue model. This work introduces a strategy for defining a set of landmark points in reference to a general 3-D representation of tongue structure. The landmarks define locations of anatomical significance that have identifiable geometric coordinates. They constitute common reference points for a mathematical mapping between any pair of data sets and indicate the anatomical correspondence, or homology, between the data sets. The integration of different data sets of the human tongue is based on this correspondence, and it is achieved by a method of nonuniform geometrical transformation (thin-plate spline mapping). We show the feasibility of these methods by mapping from muscle anatomy, according to a detailed hand-drawn dissection study [K. Miyawaki, Ann. Bul. RILP, Univ. Tokyo 8, 23–50 (1974)], against atlas images from freshly deep-frozen samples (Visible M...
The Journal of the Acoustical Society of America, 1996
The view that individual speaker characteristics reflect morphological and functional differences... more The view that individual speaker characteristics reflect morphological and functional differences in the speech apparatus has been accepted as self-evident despite the lack of convincing empirical data. A recent study on the issue of individual differences based on x-ray microbeam data from ten American English and ten Japanese speakers (five males and five females in each group) has pointed to a significance of morphology in accounting for speaker characteristics of vowel gesture. The midsagittal form of a speaker’s orofacial structure was parametrized by several landmarks on x-ray scan images. A few points and lines were chosen to form a quadrilateral framework so that they define a geometrical ‘‘articulatory space’’ where articulation of the tongue–jaw complex takes place. Pellet data for vowels were mapped onto speaker’s articulatory space to observe the effect of morphological difference on vowel articulation. Preliminary results have shown the extent of morphological variation...
The Journal of the Acoustical Society of America, 1992
An X-window-based graphics tool was developed to load serial images of histological sections of t... more An X-window-based graphics tool was developed to load serial images of histological sections of tongue specimens from a fetus available in the OSU College of Medicine, to enter contours and fiber directions of both intrinsic and extrinsic tongue muscles, and to implement a 3-D reconstruction of the tongue based on the assumption of lateral symmetry of the human tongue. It allows interactive loading of scanned-in images and their displays, sketching and labeling of various anatomical structures, and saving the sketches to files. The 3-D display of the sketches serves to construct a network of nodal points for a finite element representation. The intrinsic properties of the tissue, such as fiber direction, affiliation of local fiber directions with muscle types are compiled for each finite element. This tissue representation will be used later for the finite element analysis to simulate the deformation and movements of the tongue. The overall purpose of this study is to develop a comp...
The Journal of the Acoustical Society of America, 2010
The purpose of this research is to develop a software-based simulation platform for hearing aid a... more The purpose of this research is to develop a software-based simulation platform for hearing aid and to provide an assistive tool for clinician. User can experience hearing aid function and choose suitable hearing aid via the hearing aid simulation platform. The platform contains microphone input, noise reduction, wide dynamic range compression (WDRC), and feedback cancellation. The main purpose of this study was to simulate noise reduction and feedback cancellation by using patent documents of GN ReSound Canta, Sonic Innovation Natura, and Oticon Syncro. We evaluated the noise reduction efficiency by using subjective quality evaluation (waveform, spectrogram, listening) as well as objective quality evaluation (segmental SNR, log-spectral distance). The result shows that speech quality, signal to noise ratio, and listening comfort were improved. We also simulated feedback signals with KEMAR feedback path impulse responses and showed the three simulated feedback cancellation algorithm...
The Journal of the Acoustical Society of America, 2006
The main objective of this study is to build an MRI-based 3-D tongue atlas with an established av... more The main objective of this study is to build an MRI-based 3-D tongue atlas with an established available spatial transformation technique. The subjects for the MRI data were eight male and eight female college students (19–28 years old) who are native speakers of mandarin with Taiwanese accent without speech disorders. The oral MR images (axial: TR, 400 ms; TE, 10 ms, FOV 24×24; image matrix, 256×256 for 35 slices with 2-mm thickness) were acquired using a GE SIGNA 1.5-T scanner in the University Hospital of Chung Shan Medical University. The axial MR images of the human tongue were first segmented with snakes active contour method, then the 3-D tongues of each subject were reconstructed with morphology-based gray-level interpolation. Finally, these 3-D tongues were spatial transformed into a 3-D tongue atlas with thin-plate spline method. The 3-D tongue atlases for male and female subjects and morphometric studies, such as subject-to-subject, subject-to-atlas, and male-to-female, o...
The Journal of the Acoustical Society of America, 2006
This study evaluated the effects of binaurally combined electric and acoustic hearing on Mandarin... more This study evaluated the effects of binaurally combined electric and acoustic hearing on Mandarin speech recognition under simulated background noise for normal-hearing (NH) listeners and CI recipients of the Nucleus-24 device with contralateral hearing aid (HA). Chinese word and tone recognition were measured in seven NH subjects using simulated four-channel continuous interleaved sampler (CIS) type speech processing strategy under three different conditions, namely, (1) only simulated (CI) signals with modulated Gaussian white noise for monaural stimulation, (2) simulated (CI) signals with modulated Gaussian white noise and simulated HA signals (low-pass speech signals with cutoff frequency of 500 Hz) for monaural stimulation, and (3) simulated (CI) signals with modulated Gaussian white noise to one ear and simulated hearing aid (HA) signals to the other ear for dichotic stimulation. For comparison purposes, Chinese word and tone recognition were also measured in three CI users us...
The Journal of the Acoustical Society of America, 1997
This report describes the design, data structure, and applicability of a refined finite-element t... more This report describes the design, data structure, and applicability of a refined finite-element template for the human tongue and connected oral structures. The finite-element model relies mainly on data sets from the Visible Human Project of the National Library of Medicine. The model is composed of macroblocks, which represent geometric subsections of the tongue. These blocks represent, in some cases, either individually or in combination, functional subsections, such as individual muscles. For each macroblock (or geometric region) a finite-element mesh can be generated such that the whole of the tongue can be modeled by a mesh of finite-elements, since the subdivision is compatible across block boundaries. The finite element template contains information about muscle tissue distribution of the tongue and velopharynx. Approximate muscle fiber directions are represented as direction fields. The model can be adapted to individual morphology if a set of morphological landmarks can be...
The Journal of the Acoustical Society of America, 1991
An approximate computational model of the tongue including both intrinsic and extrinsic muscles h... more An approximate computational model of the tongue including both intrinsic and extrinsic muscles has been constructed based on histological sections of tongue specimens. The tongue is represented by several geometrical solid primitives (blocks) forming local curvilinear coordinate systems, in reference to which muscle fiber directions are specified. Control vertices serve as reference points for each block, and their positional variation allows anatomical scaling. Each block is divided into several finite elements, within each of which fiber directions and muscle activation parameters are computed using linear and quadratic interpolation. The deformation and movement of the tongue is simulated by solving the equations of motion, assuming large deformation and incompressibility of the continuum. A new algorithm has been devised for maintaining deformations isochoric, using a projection method for reduced stress computation. The muscular stresses are computed with a simple model of mus...
Objective: ElectrodeNet, a deep-learning based sound coding strategy for the cochlear implant (CI... more Objective: ElectrodeNet, a deep-learning based sound coding strategy for the cochlear implant (CI), is proposed in this study. The performance between ElectrodeNet and the advanced combination encoder (ACE) coding strategy in speech intelligibility is compared. Methods: ElectrodeNet emulates the ACE strategy and replaces the conventional envelope detection using various forms of artificial neural networks. Network models of deep neural network (DNN), convolutional neural network (CNN), and long short-term memory (LSTM) were trained using the fast Fourier transformed clean speech and the corresponding electrode stimulation patterns. Objective speech intelligibility was estimated for ElectrodeNets for the factors of loss function, network architecture, language, and noise type. Subjective listening tests for vocoded Mandarin speech were conducted with 40 normal-hearing listeners. Results: DNN, CNN, and LSTM based ElectrodeNets exhibited strong correlations with the ACE strategy in sho...
2001 Conference Proceedings of the 23rd Annual International Conference of the IEEE Engineering in Medicine and Biology Society
ABSTRACT People with speech impairments are likely to also have varied movement disorders which r... more ABSTRACT People with speech impairments are likely to also have varied movement disorders which result in the inability to use existing voice telephone facility. The aim of this research is to extend the current augmentative and alternative communication (AAC) system to wireless telecommunication service, for speech-impaired subjects. A pocket personal computer (PPC) with a Global System for Mobile Communications (GSM) module is adopted herein. The touch screen of PPC with designed graphics icon can be used as large buttons to activate the high-fidelity sound that is in turns sent to the GSM module for "talking" through the phone. An AAC layout editor is used to link the pre-recorded sound to the graphics icon and to compile the icon-based graphics for each individual. In addition, levels of dynamic linkages, including script-based, category of use, semantic linkage, and frequency of use are implemented for assisting the speech impairment user to retrieve these pre-stored conversational items which can speed up the communication rate.
The purpose of this research was to add a speech enhancement process that could further improve s... more The purpose of this research was to add a speech enhancement process that could further improve speech intelligibility and the performance of automatic scene classification and automatching noise reduction system after the application of the adaptive directional microphone strategy. The speech enhancement system is divided into two parts: one is the noise-estimation strategy and the other the speech-estimation function. Noise-estimation algorithms used in the research are: minimum statistics (MS), minima-controlled recursive averaging (MCRA),improved(IMCRA), MCRA-Loizou (MCRA-L), constrained variance spectral smoothing (CVS), forward-backward MCRA(MCRA-FB);speech-estimation function: Wiener filter, maximum-likelihood (ML), log-spectral amplitude (LSA), maximum a posteriori amplitude (MAPA).In this research, The MATLAB program was first used to simulate the speech enhancement system to evaluate the quality of output speech signal under different signal-to-noise ratio (SNR) conditions...
Journal of Medical and Biological Engineering, 2008
Eye-writing herein introduced is a novel language communication method wherein the eyes fill the ... more Eye-writing herein introduced is a novel language communication method wherein the eyes fill the role of a writing organ. An eye-writing system detects the traces of eye movements and determines their corresponding symbols by pattern recognition. In this study, we measured the eye movements by electro-oculograophy (EOG). The electrical potential difference measured between the skins above and below the eyes reflected the eye movement in the vertical direction. That measured between tire skins to the left and to tire right of tire eyes reflected tire eye movement in tire horizontal direction. We evaluated the eye-writing system with a symbol set consisting of symbols of 10 Arabic numerals and 4 mathematic operators. Experiments on 11 voluntary human subjects shunned recognition rate ranging from 50% to 100% with different symbols. The recognition rate can be improved by several means to reads a desired level for practical applications. We conclude that eye-writing as a language commu...
The DIMX (Directions Into Velocities Articulator) model provides a computatienal and ncuroanatomi... more The DIMX (Directions Into Velocities Articulator) model provides a computatienal and ncuroanatomical account of speech acquisition and production; however, its prediction of speech perception and production for Mandarin is limited. The aim of this study is to modify the original DIMdL model to simulate both norrnal and speech disordered productions in Mandarin. The proposed version of the model provides aclditional functions of speech perception, tonal acquisition and diphthong production. Computer simulation of our modified DIVfiL model verifies its ability to simulate Mandarin tenal production in diphthong arid speech perception across vowels.
Evidence-Based Complementary and Alternative Medicine, 2018
Background. The Auto Manipulation Device for Acupuncture (AMDA) is designed for providing stable,... more Background. The Auto Manipulation Device for Acupuncture (AMDA) is designed for providing stable, quantified effects and higher frequency when doing lifting and thrusting manipulation. The purpose of this study is to investigate the safety of manipulation by AMDA in different frequency and duration in healthy rats. Methods. The study was divided into two parts: single intervention and once a day for a week. 12 rats and 15 rats were randomly allocated to different groups: Control (needle insertion only), AMDA (2Hz/10Mins), AMDA (2Hz/20Mins), AMDA (20Hz/10Mins), and AMDA (20Hz/20Mins) for single and repeated interventions. Real-time physiological functions, laboratory data, and the bilateral muscle tissue of acupoint (ST 36) were obtained after the intervention. Results. We found neither real-time physiological functions nor laboratory data differences between control group and AMDA groups in both parts. In the muscle tissue samples, the slight damage had been observed in the AMDA gro...
Disability and rehabilitation. Assistive technology, Aug 7, 2015
The purpose of this study is to develop a tool to assist speech therapy and rehabilitation, which... more The purpose of this study is to develop a tool to assist speech therapy and rehabilitation, which focused on automatic scoring based on the comparison of the patient's speech with another normal speech on several aspects including pitch, vowel, voiced-unvoiced segments, strident fricative and sound intensity. The pitch estimation employed the use of cepstrum-based algorithm for its robustness; the vowel classification used multilayer perceptron (MLP) to classify vowel from pitch and formants; and the strident fricative detection was based on the major peak spectral intensity, location and the pitch existence in the segment. In order to evaluate the performance of the system, this study analyzed eight patient's speech recordings (four males, four females; 4-58-years-old), which had been recorded in previous study in cooperation with Taipei Veterans General Hospital and Taoyuan General Hospital. The experiment result on pitch algorithm showed that the cepstrum method had 5.3% ...
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference, 2014
Needle lifting and thrusting manipulation is one of common skills in acupuncture. However, there ... more Needle lifting and thrusting manipulation is one of common skills in acupuncture. However, there exists artificial error in frequency and amplitude due to individual difference when performing lifting and thrusting during acupuncture. For providing stable and quantified effects and higher frequency when doing lifting and thrusting manipulation, a well controlled device is needed. The aim of this article is to report the preliminary results of the development of Auto Manipulation Device for Acupuncture (AMDA) and characterization of its functional parameters. A tissue-simulating Agar gel phantom with 4.8%, 5.2%, and 5.4% concentrations was prepared and used for characterization of the AMDA. Tests of the linearity, reliability and safety of the AMDA were implemented with conditions of different drive voltages, frequencies, and simulated tissues. Our preliminary results have demonstrated the developed AMDA its plausibility in the clinical application of acupuncture.
ABSTRACT Eye-writing herein introduced is a novel language communication method wherein the eyes ... more ABSTRACT Eye-writing herein introduced is a novel language communication method wherein the eyes fill the role of a writing organ. An eye-writing system detects the traces of eye movements and determines their corresponding symbols by pattern recognition. In this study, we measured the eye movements by electro-oculograophy (EOG). The electrical potential difference measured between the skins above and below the eyes reflected the eye movement in the vertical direction. That measured between the skins to the left and to the right of the eyes reflected the eye movement in the horizontal direction. We evaluated the eye-writing system with a symbol set consisting of symbols of 10 Arabic numerals and 4 mathematic operators. Experiments on 11 voluntary human subjects showed recognition rate ranging from 50% to 100 % with different symbols. The recognition rate can be improved by several means to reach a desired level for practical applications. We conclude that eye-writing as a language communication method is feasible. This technology will be especially useful for severe amyotrophic lateral sclerosis (ALS) patients who have lost the oral-speaking and hand-writing abilities.
The Journal of the Acoustical Society of America, 2008
The main purpose of this study is to build a MRI-based 3D tongue atlas for research on tongue mor... more The main purpose of this study is to build a MRI-based 3D tongue atlas for research on tongue morphometrics and physiological modeling of normal and disordered speech production. In this study, MRI data of 8 subjects (4 males and 4 females) were chosen from an orally-based MRI database of 20 male and 20 female college students without speech disorders. Sixteen landmarks were defined and selected from the 3D reconstructed MRI tongue images based on the subjects. Thin-plate spline analysis (TPS) was used to build a 3D tongue atlas for male and female subjects, respectively. Sagittal sections of the original MRI data were used to evaluate the accuracy of image registration and reconstruction. The resulted 3D tongue atlas was used to study subject-to subject, subject-to-atlas, and male-to-female morphometric variation. Preliminary results show the major difference among female subjects before and after the TPS analysis is in the area of tongue dorsum that is close to the velum and epigl...
The Journal of the Acoustical Society of America, 1996
The main objective of this work is to obtain reliable and detailed anatomical information for dev... more The main objective of this work is to obtain reliable and detailed anatomical information for developing a quantitative 3-D tongue model. This work introduces a strategy for defining a set of landmark points in reference to a general 3-D representation of tongue structure. The landmarks define locations of anatomical significance that have identifiable geometric coordinates. They constitute common reference points for a mathematical mapping between any pair of data sets and indicate the anatomical correspondence, or homology, between the data sets. The integration of different data sets of the human tongue is based on this correspondence, and it is achieved by a method of nonuniform geometrical transformation (thin-plate spline mapping). We show the feasibility of these methods by mapping from muscle anatomy, according to a detailed hand-drawn dissection study [K. Miyawaki, Ann. Bul. RILP, Univ. Tokyo 8, 23–50 (1974)], against atlas images from freshly deep-frozen samples (Visible M...
The Journal of the Acoustical Society of America, 1996
The view that individual speaker characteristics reflect morphological and functional differences... more The view that individual speaker characteristics reflect morphological and functional differences in the speech apparatus has been accepted as self-evident despite the lack of convincing empirical data. A recent study on the issue of individual differences based on x-ray microbeam data from ten American English and ten Japanese speakers (five males and five females in each group) has pointed to a significance of morphology in accounting for speaker characteristics of vowel gesture. The midsagittal form of a speaker’s orofacial structure was parametrized by several landmarks on x-ray scan images. A few points and lines were chosen to form a quadrilateral framework so that they define a geometrical ‘‘articulatory space’’ where articulation of the tongue–jaw complex takes place. Pellet data for vowels were mapped onto speaker’s articulatory space to observe the effect of morphological difference on vowel articulation. Preliminary results have shown the extent of morphological variation...
The Journal of the Acoustical Society of America, 1992
An X-window-based graphics tool was developed to load serial images of histological sections of t... more An X-window-based graphics tool was developed to load serial images of histological sections of tongue specimens from a fetus available in the OSU College of Medicine, to enter contours and fiber directions of both intrinsic and extrinsic tongue muscles, and to implement a 3-D reconstruction of the tongue based on the assumption of lateral symmetry of the human tongue. It allows interactive loading of scanned-in images and their displays, sketching and labeling of various anatomical structures, and saving the sketches to files. The 3-D display of the sketches serves to construct a network of nodal points for a finite element representation. The intrinsic properties of the tissue, such as fiber direction, affiliation of local fiber directions with muscle types are compiled for each finite element. This tissue representation will be used later for the finite element analysis to simulate the deformation and movements of the tongue. The overall purpose of this study is to develop a comp...
The Journal of the Acoustical Society of America, 2010
The purpose of this research is to develop a software-based simulation platform for hearing aid a... more The purpose of this research is to develop a software-based simulation platform for hearing aid and to provide an assistive tool for clinician. User can experience hearing aid function and choose suitable hearing aid via the hearing aid simulation platform. The platform contains microphone input, noise reduction, wide dynamic range compression (WDRC), and feedback cancellation. The main purpose of this study was to simulate noise reduction and feedback cancellation by using patent documents of GN ReSound Canta, Sonic Innovation Natura, and Oticon Syncro. We evaluated the noise reduction efficiency by using subjective quality evaluation (waveform, spectrogram, listening) as well as objective quality evaluation (segmental SNR, log-spectral distance). The result shows that speech quality, signal to noise ratio, and listening comfort were improved. We also simulated feedback signals with KEMAR feedback path impulse responses and showed the three simulated feedback cancellation algorithm...
The Journal of the Acoustical Society of America, 2006
The main objective of this study is to build an MRI-based 3-D tongue atlas with an established av... more The main objective of this study is to build an MRI-based 3-D tongue atlas with an established available spatial transformation technique. The subjects for the MRI data were eight male and eight female college students (19–28 years old) who are native speakers of mandarin with Taiwanese accent without speech disorders. The oral MR images (axial: TR, 400 ms; TE, 10 ms, FOV 24×24; image matrix, 256×256 for 35 slices with 2-mm thickness) were acquired using a GE SIGNA 1.5-T scanner in the University Hospital of Chung Shan Medical University. The axial MR images of the human tongue were first segmented with snakes active contour method, then the 3-D tongues of each subject were reconstructed with morphology-based gray-level interpolation. Finally, these 3-D tongues were spatial transformed into a 3-D tongue atlas with thin-plate spline method. The 3-D tongue atlases for male and female subjects and morphometric studies, such as subject-to-subject, subject-to-atlas, and male-to-female, o...
The Journal of the Acoustical Society of America, 2006
This study evaluated the effects of binaurally combined electric and acoustic hearing on Mandarin... more This study evaluated the effects of binaurally combined electric and acoustic hearing on Mandarin speech recognition under simulated background noise for normal-hearing (NH) listeners and CI recipients of the Nucleus-24 device with contralateral hearing aid (HA). Chinese word and tone recognition were measured in seven NH subjects using simulated four-channel continuous interleaved sampler (CIS) type speech processing strategy under three different conditions, namely, (1) only simulated (CI) signals with modulated Gaussian white noise for monaural stimulation, (2) simulated (CI) signals with modulated Gaussian white noise and simulated HA signals (low-pass speech signals with cutoff frequency of 500 Hz) for monaural stimulation, and (3) simulated (CI) signals with modulated Gaussian white noise to one ear and simulated hearing aid (HA) signals to the other ear for dichotic stimulation. For comparison purposes, Chinese word and tone recognition were also measured in three CI users us...
The Journal of the Acoustical Society of America, 1997
This report describes the design, data structure, and applicability of a refined finite-element t... more This report describes the design, data structure, and applicability of a refined finite-element template for the human tongue and connected oral structures. The finite-element model relies mainly on data sets from the Visible Human Project of the National Library of Medicine. The model is composed of macroblocks, which represent geometric subsections of the tongue. These blocks represent, in some cases, either individually or in combination, functional subsections, such as individual muscles. For each macroblock (or geometric region) a finite-element mesh can be generated such that the whole of the tongue can be modeled by a mesh of finite-elements, since the subdivision is compatible across block boundaries. The finite element template contains information about muscle tissue distribution of the tongue and velopharynx. Approximate muscle fiber directions are represented as direction fields. The model can be adapted to individual morphology if a set of morphological landmarks can be...
The Journal of the Acoustical Society of America, 1991
An approximate computational model of the tongue including both intrinsic and extrinsic muscles h... more An approximate computational model of the tongue including both intrinsic and extrinsic muscles has been constructed based on histological sections of tongue specimens. The tongue is represented by several geometrical solid primitives (blocks) forming local curvilinear coordinate systems, in reference to which muscle fiber directions are specified. Control vertices serve as reference points for each block, and their positional variation allows anatomical scaling. Each block is divided into several finite elements, within each of which fiber directions and muscle activation parameters are computed using linear and quadratic interpolation. The deformation and movement of the tongue is simulated by solving the equations of motion, assuming large deformation and incompressibility of the continuum. A new algorithm has been devised for maintaining deformations isochoric, using a projection method for reduced stress computation. The muscular stresses are computed with a simple model of mus...
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Papers by Chao-Min Wu