Sound Distortion Research Articles

Dysphagia Intervention in Patient with Diffusion Axon Injury with Bilateral Frontal Lobe Contusion: A Case Report

Introduction: Traumatic brain injury (TBI) is a leading cause of chronic neurologic disability. Damage often affects the frontal lobes, and thus the most frequent cognitive sequelae are deficits in the prefrontal cortex (PFC)-dependent functions, such as attention, working memory, social behavior, mental flexibility, and task switching. Objective: The goal of this case report is to highlight the assessment and intervention of the dysphagia program. Case Report: The patient was diagnosed with diffuse axonal injury with bilateral frontal lobe contusion. The patient is receiving care in the Physical Medicine and Rehabilitation (PMR) unit, where they are undergoing physiotherapy occupational therapy, and speech therapy. Results: Speech Assessment revealed deviated voice and resonance characteristics with Substitution & Distortion of speech sounds. Swallowing assessment revealed Oro-pharyngeal Dysphagia. The patient was also undergoing Chemotherapy and Radiation-therapy. Recommendations for further follow-ups for speech & swallowing therapy and other medical management were made. Conclusion: This study is useful in creating evidence regarding the assessment & rehabilitation of Speech and swallowing in patients undergoing hemi-glossectomy. It also emphasizes the input from other medical professionals as an interdisciplinary team member.

Optimal audio beam pattern synthesis for an enhanced parametric array loudspeaker

A parametric array loudspeaker (PAL) generates highly directional audible sound in air with a small aperture size compared to a conventional loudspeaker. But in indoor applications, the long propagation distance of a PAL causes reflections, which disturbs the reproduction of narrow audio beams. Moreover, sound distortion appears along the off-axis direction due to the frequency dependence of the beam width. This study proposed an optimal audio beam pattern synthesis for a PAL-based convex optimization, which can design the audio beam of a PAL with an optimal solution. The proposed method overcame the mentioned limitations by applying it to a length-limited PAL for audio spot control and a multichannel PAL array for a constant beam width audio beam. In a length-limited PAL, the proposed method restricts the audio spot to a smaller region and weakens the sound leakage along the off-axis direction. Whereas in a multichannel PAL array, the proposed method also achieves a constant beam width near the radiator axis. Simulations and experiments verify the effectiveness of the proposed method, which will enhance the performance of a PAL in scenarios where control of the audio beam is required.

An online survey of clinical practice and confidence in diagnosing acquired apraxia of speech in Cantonese speakers

Purpose The assessment and diagnosis of apraxia of speech (AOS) have been well studied in the English context, yet there is limited understanding of the clinical practice in speakers of other languages, like Cantonese. This study aimed to obtain information about the clinical practice of assessment methods and diagnostic criteria used, and confidence in diagnosing, AOS in Cantonese speakers. Method An online survey constructed with Google Forms was completed by 27 speech-language pathologists (SLPs) in Hong Kong. The questionnaire comprised 12 questions covering (a) demographic information, (b) experience working with speakers with AOS, (c) confidence in making AOS diagnosis in Cantonese speakers, (d) assessment tasks or methods used for assessing AOS in Cantonese speakers, (e) clinical features used for diagnostic purposes, and (f) assessment tasks used to determine the presence of clinical features for diagnostic purposes. Result All respondents (100%) made AOS diagnoses based on the observed clinical features, while no respondents made diagnoses using only standardised tests or quantitative measures. Six clinical features were commonly used by most of the respondents: articulatory groping (100%), inconsistent articulatory errors (100%), length effects (85.2%), difficulty initiating speech (81.5%), automaticity effects (81.5%), and sound distortions (77.8%). More than half of the respondents collected connected speech samples (64%), and conducted diadochokinesis (64%) and repetition tasks (64%). The average confidence level of the respondents for making AOS diagnoses was fair (3.63/5). Conclusion The SLPs in Hong Kong make AOS diagnoses based on the observed clinical features that have been reported in the English literature. Although some of the clinical features have been updated as non-discriminatory for AOS, they are still being used for AOS diagnosis in Cantonese speakers. Tendencies were observed with respect to the assessment tasks selected. The fair diagnostic confidence level suggests a need for future investigations of AOS in Cantonese speakers and the development of assessment tools.

Sound distortions of phraseological units in modern Russian speech

Sound distortions of phraseological units in modern Russian speech

High level sound transmission through cadaver human ears—On the influence of bone conduction and hearing protective devices

High level sound exposure can cause substantial injury to the auditory system, motivating efforts to predict and prevent this injury. Measurement techniques using acoustic manikins are effective for low and moderate sound levels, but nonlinear effects in the middle ear and alternate sound transmission pathways to the inner ear limit their utility at higher sound pressure levels. Here, we describe results from a series of measurements made in cadaveric human ears conducted in our laboratory over the last several years. We quantified sound transmission to the inner ear by measuring the difference in sound pressure level across the cochlear partition near the base of the cochlea, which drives basilar membrane motion. We describe measurements quantifying sound transmission through the human middle ear, which is limited by suspensory ligaments for sounds above approximately 130 dB SPL, resulting in nonlinear (harmonic) distortion of sounds in the cochlea at higher sound pressure levels. Similarly, we describe observations of sound transmission to the cochlea via bone conduction from vibratory transducers, as well as high level sound and impulse noise/blast exposures. The implications of these measurements for hearing loss predictions, effectiveness of hearing protective devices, and injury mechanisms are discussed.

A constrained multi-channel hear-through filter design approach using active control formulations

In many daily communication environments, especially during a pandemic era, partitioning structures are placed between people for security or virus concerns, for example, partitions in classrooms, banks, and retail stores. Distortion occurs when sound propagates through these partitions, which can cause distractions in communication and degrade the service quality. In the current work, a constrained multi-channel active hear-through system is proposed to provide a solution to provide more natural sound communication environments and prevent sound distortions due to partitioning structures. The proposed method can preserve both the spectrum and the spatial distribution of the original sound field (the sound field when the partition is absent). This research opens the potential for future development of multi-channel two-way communication systems and improvement in existing augmented reality techniques. Experimental results show that, compared with the traditional direct inverse filter design method, the proposed method can reduce the comb-filtering effect effectively. The constraints applied to the filter design procedure can also prevent instability caused by the acoustic feedback loop.

Reliable characterization of sound features in fishes begins in open-water environmentsa).

Many fishes use sounds to communicate in a wide range of behavioral contexts. In monitoring studies, these sounds can be used to detect and identify species. However, being able to confidently link a sound to the correct emitting species requires precise acoustical characterization of the signals in controlled conditions. For practical reasons, this characterization is often performed in small sized aquaria, which, however, may cause sound distortion, and prevents an accurate description of sound characteristics that will ultimately impede sound-based species identification in open-water environments. This study compared the sounds features of five specimens of the silverspot squirrelfish Sargocentron caudimaculatum recorded at sea and in aquaria of different sizes and materials. Our results point out that it is preferable to record fish sounds in an open-water environment rather than in small aquaria because acoustical features are affected (sound duration and dominant frequency) when sounds are recorded in closed environments as a result of reverberation and resonance. If not possible, it is recommended that (1) sound recordings be made in plastic or plexiglass aquaria with respect to glass aquaria and (2) aquaria with the largest dimensions and volumes be chosen.

Apraxia of Speech in the Spontaneous Speech of Nonfluent/Agrammatic Primary Progressive Aphasia.

Apraxia of speech (AOS) is a core feature of nonfluent/agrammatic primary progressive aphasia (naPPA), but its precise characteristics and the prevalence of AOS features in spontaneous speech are debated. To assess the frequency of features of AOS in the spontaneous, connected speech of individuals with naPPA and to evaluate whether these features are associated with an underlying motor disorder such as corticobasal syndrome or progressive supranuclear palsy. We examined features of AOS in 30 patients with naPPA using a picture description task. We compared these patients to 22 individuals with behavioral variant frontotemporal dementia and 30 healthy controls. Each speech sample was evaluated perceptually for lengthened speech segments and quantitatively for speech sound distortions, pauses between and within words, and articulatory groping. We compared subgroups of naPPA with and without at least two features of AOS to assess the possible contribution of a motor impairment to speech production deficits. naPPA patients produced both speech sound distortions and other speech sound errors. Speech segmentation was found in 27/30 (90%) of individuals. Distortions were identified in 8/30 (27%) of individuals, and other speech sound errors occurred in 18/30 (60%) of individuals. Frequent articulatory groping was observed in 6/30 (20%) of individuals. Lengthened segments were observed rarely. There were no differences in the frequencies of AOS features among naPPA subgroups as a function of extrapyramidal disease. Features of AOS occur with varying frequency in the spontaneous speech of individuals with naPPA, independently of an underlying motor disorder.

Apraxia of Speech in the Spontaneous Speech of Nonfluent/Agrammatic Primary Progressive Aphasia

Background: Apraxia of speech (AOS) is a core feature of nonfluent/agrammatic primary progressive aphasia (naPPA), but its precise characteristics and the prevalence of AOS features in spontaneous speech are debated. Objective: To assess the frequency of features of AOS in the spontaneous, connected speech of individuals with naPPA and to evaluate whether these features are associated with an underlying motor disorder such as corticobasal syndrome or progressive supranuclear palsy. Methods: We examined features of AOS in 30 patients with naPPA using a picture description task. We compared these patients to 22 individuals with behavioral variant frontotemporal dementia and 30 healthy controls. Each speech sample was evaluated perceptually for lengthened speech segments and quantitatively for speech sound distortions, pauses between and within words, and articulatory groping. We compared subgroups of naPPA with and without at least two features of AOS to assess the possible contribution of a motor impairment to speech production deficits. Results: naPPA patients produced both speech sound distortions and other speech sound errors. Speech segmentation was found in 27/30 (90%) of individuals. Distortions were identified in 8/30 (27%) of individuals, and other speech sound errors occurred in 18/30 (60%) of individuals. Frequent articulatory groping was observed in 6/30 (20%) of individuals. Lengthened segments were observed rarely. There were no differences in the frequencies of AOS features among naPPA subgroups as a function of extrapyramidal disease. Conclusion: Features of AOS occur with varying frequency in the spontaneous speech of individuals with naPPA, independently of an underlying motor disorder.

A constrained multi-channel hear-through filter design approach using active control formulations

In many daily communication environments, especially during the pandemic era, partitioning structures are placed between people for security or virus concerns, for example, partitions in classrooms, banks, retail stores, etc. . Distortion occurs when sound propagates through these partitions can cause distractions in communication and degrade the service quality. In the current work, a constrained multi-channel active hear-through system is proposed to provide a solution to provide more natural sound communication environments and prevent sound distortions due to portioning structures. The proposed method can preserve both the spectrum and the spatial distribution of the original sound field (the sound field when the partition is absent). This research opens the potential for future development of multi-channel two-way communication systems and improvement in existing augmented reality techniques. Experimental results show that, compared with the traditional direct inverse filter design method, the proposed method can reduce the comb-filtering effect effectively. The constraints applied to the filter design procedure can also prevent instability caused by the acoustic feedback loop.

Heart sounds classification using adaptive wavelet threshold and 1D LDCNN

Heart sounds classification plays an important role in cardiovascular disease detection. Currently, deep learning methods for heart sound classification with heavy parameters consumption cannot be deployed in environments with limited memory and computational budgets. Besides, de-noising of heart sound signals (HSSs) can affect accuracy of heart sound classification, because erroneous removal of meaningful components may lead to heart sound distortion. In this paper, an automated heart sound classification method using adaptive wavelet threshold and 1D LDCNN (One-dimensional Lightweight Deep Convolutional Neural Network) is proposed. In this method, we exploit WT (Wavelet Transform) with an adaptive threshold to de-noise heart sound signals (HSSs). Furthermore, we utilize 1D LDCNN to realize automatic feature extraction and classification for de-noised heart sounds. Experiments on PhysioNet/CinC 2016 show that our proposed method achieves the superior classification results and excels in consumption of parameter comparing to state-of-the-art methods.

Mobile Communication Voice Enhancement Under Convolutional Neural Networks and the Internet of Things

This study aims to reduce the interference of ambient noise in mobile communication, improve the accuracy and authenticity of information transmitted by sound, and guarantee the accuracy of voice information delivered by mobile communication. First, the principles and techniques of speech enhancement are analyzed, and a fast lateral recursive least square method (FLRLS method) is adopted to process sound data. Then, the convolutional neural networks (CNNs)-based noise recognition CNN (NR-CNN) algorithm and speech enhancement model are proposed. Finally, related experiments are designed to verify the performance of the proposed algorithm and model. The experimental results show that the noise classification accuracy of the NR-CNN noise recognition algorithm is higher than 99.82%, and the recall rate and F1 value are also higher than 99.92. The proposed sound enhancement model can effectively enhance the original sound in the case of noise interference. After the CNN is incorporated, the average value of all noisy sound perception quality evaluation system values is improved by over 21% compared with that of the traditional noise reduction method. The proposed algorithm can adapt to a variety of voice environments and can simultaneously enhance and reduce noise processing on a variety of different types of voice signals, and the processing effect is better than that of traditional sound enhancement models. In addition, the sound distortion index of the proposed speech enhancement model is inferior to that of the control group, indicating that the addition of the CNN neural network is less likely to cause sound signal distortion in various sound environments and shows superior robustness. In summary, the proposed CNN-based speech enhancement model shows significant sound enhancement effects, stable performance, and strong adaptability. This study provides a reference and basis for research applying neural networks in speech enhancement.

Application of Neural Network and Virtual Reality Technology in Digital Video Effects

With the continuous innovation of technology, digital technology is more and more widely used in the production of TV shows and movies and plays an important role. The effective application of digital video effects technology can enhance the visual effects of the overall TV and film works and improve the quality of the works. After the use of digital special effects in film and television production, people see more exquisite film and television pictures, but today’s technology is not enough to meet people’s growing demand for film and television pictures. This paper applied neural network and virtual reality technology to the production process of digital video effects and conducted a comparative experiment with the digital video effects produced by using the current technology. The special effects were evaluated in four aspects: image fidelity, sound distortion, picture fluency, and production efficiency. The experimental results show that after applying neural network and virtual reality technologies, the image fidelity of digital video effects is increased by 6.74%, the sound distortion is reduced by 7.69%, the picture fluency is increased by 6.89%, and the production efficiency is increased by 7.91%. Applying the neural network and virtual reality technology can improve the quality and efficiency of digital video special effects production.

Design and Realization of MEMS Heart Sound Sensor with Concave, Racket-Shaped Cilium.

The biomedical acoustic signal plays an important role in clinical non-invasive diagnosis. In view of the deficiencies in early diagnosis of cardiovascular diseases, acoustic properties of S1 and S2 heart sounds are utilized. In this paper, we propose an integrated concave cilium MEMS heart sound sensor. The concave structure enlarges the area for receiving sound waves to improve the low-frequency sensitivity, and realizes the low-frequency and high-sensitivity characteristics of an MEMS heart sound sensor by adopting a reasonable acoustic package design, reducing the loss of heart sound distortion and faint heart murmurs, and improving the auscultation effect. Finally, experimental results show that the integrated concave ciliated MEMS heart sound sensor’s sensitivity reaches −180.6 dB@500 Hz, as compared with the traditional bionic ciliated MEMS heart sound sensor; the sensitivity is 8.9 dB higher. The sensor has a signal-to-noise ratio of 27.05 dB, and has good heart sound detection ability, improving the accuracy of clinical detection methods.

Design of parametric acoustic array based on inverse control processing

The parametric acoustic array (PAA) is a new acoustic system that can produce directional acoustic beams, but due to the nonlinear influence of media, it will produce severe distortion during propagation. In order to obtain high-quality audible sound, the system should take full advantage of the nonlinear propagation effect of air and minimize the distortion caused by non-linearity. Presented in this paper is a method of using a nonlinear control algorithm to reduce system distortion. The inverse model of the parametric array nonlinear system is established using a neural network. The effectiveness of this control algorithm is verified by the inverse control simulation of different types of audio signals. According to the established system model, the sound distortion of the system is reduced effectively. In order to optimize the directivity of the speaker array, a method based on changing the distribution of the transducer voltage is proposed. This study has important implications for the directed propagation of audible sounds in the air.

Validating Spectral Moment Analysis as a Quantitative Measure of Speech Distortions in Speakers With Class III Malocclusions.

This study examined the relationship between judged speech sound distortions and spectral moment metrics in speakers with Class III malocclusion. A quantitative online survey was distributed to 30 speech specialists (clinicians and/or students) and 100 lay listeners to judge the clarity of the sounds /s/, /ʃ/, /t/ and /k/ using a visual analog scale (VAS) from recordings of 11 Class III (underbite) Dentofacial Disharmony (DFD) patients and eight Class I controls. Patients and controls were grouped according to high, moderate, and low /s/-/ʃ/ first spectral moment differences. A linear mixed model was used to analyze the data. VAS scale ratings increased as a function of decreasing spectral contrast for both groups of listeners. VAS ratings of speech specialists were more homogenous than lay listeners, and speech specialists rated distortions as less severe than lay listeners. Recordings of Class III DFD patients with low /s/-/ʃ/ first spectral moment differences were scored by listeners as having increased VAS scale ratings, indicative of more significant perceived speech-sound distortions. Spectral moment analysis appears to be a promising approach for characterizing speech of DFD patients and other craniofacial disorders.

Back-projection method with fast time-delay correction for photoacoustic tomography reconstruction based on a focused sound field model

Photoacoustic tomography is a rapidly developing imaging technology, which can provide structural and functional information of biological tissues. It can integrate the advantage of high optical contrast from optical imaging with those from high penetration depth from ultrasound imaging. However, the existing back-projection algorithm in photoacoustic tomography equates the ultrasonic transducer scanning around the target to a point detector, which leads to a notable tangential blur in the eccentric imaging regions, and thus seriously degrading the image quality. In this paper, we propose a novel photoacoustic tomography reconstruction algorithm, which employs a focused sound field equivalent model to overcome the sound field distortion caused by the transducer’ finite aperture effect and can quickly and effectively restore the elongated tangential resolution in the eccentric imaging regions. Simulation results show that for the target with a diameter of 5 mm and a distance of 6 mm from the rotation center, the tangential resolution is improved by at least twice. Experimental results show that this method can effectively restore the image tangential blur in the off-center regions, where the tiny structures of complex targets can be detected. This new method provides a valuable alternative to the conventional back-projection method and plays an important guiding role in the design of photoacoustic tomography systems based on circle/sphere scanning.

Fuzzy Theory-based Air Valve Control for Auto-Score-Recognition Soprano Recorder Machines

In the past research, there are many disadvantages to score recognition and flute performance. In view of this, we will improve the above disadvantages in this article. First, for the music score recognition, a y-axis projection method is used to detect the staff position and eliminate it to replace the erosion and expansion in morphology. This feature can be used to distinguish the notes, which have a specific writing style on the staff. For the soprano recorder playing, in the past we used finger-shaped electric arms to press the blow hole to cause that the speed of the score cannot be kept up. To improve this drawback, the motor is changed to a solenoid valve to facilitate the pneumatic cylinder to smoothly press the blow hole. In addition, since the difference in pitch of the soprano recorder requires different air pressure, we increase one valve to three valves. Moreover, the range is divided into bass, midrange, and treble. Not only that, fuzzy theory-based air valve control is applied to auto-score-recognition soprano recorder machines to greatly improve the sound distortion caused by the original single air valve. Experiments prove that the fuzzy theory-based air valve control combined with sheet music recognition techniques can fully realize the functions of autoplaying soprano recorder machines.

음향창 박리에 따른 음향투과특성 연구

This paper investigated sound characteristics by the delamination of an acoustic window. In detail, acoustic scattering and transmission characteristics on the delaminated acoustic window were estimated using an experimental and numerical approach. The experiment results showed that acoustic wave could lose its amplitude and take phase delay when it propagates the delaminated acoustic window. The numerical results showed that scattering phenomena occur on the delamination surface. The scattering characteristics presented differently according to the delamination size in the acoustic window. It also showed that transmitted sound distortion due to delamination could cause a direction detection error of SONAR by changing the position of the main lobe and the magnitude of the side lobe. In conclusion, the delamination has to be managed during the manufacturing process of acoustic windows.

Коррекция нарушения звукопроизношения у старших дошкольников с фонетико-фонематическим недоразвитием речи

The research featured senior preschoolers with phonetic-phonemic speech underdevelopment. The authors described the peculiarities of speech development in such children and analyzed related publications. As a rule, impaired sound pronunciation includes low tempo and weak voluntary regulation. The study featured substitutions, distortion, or absence of various sounds. The authors tested a set of measures aimed at correcting speech disorders in senior preschool children with phonetic-phonemic speech underdevelopment. The experiment revealed a combination of incorrect pronunciation with sounds that were partially consistent in a certain context. Cognitive parameters included difficulties in memorizing verbal information and poor auditory memory. The subjects failed active speech tests and could not remember oral information. The article also introduces data on the specifics of speech therapy of phonemic hearing.