David Grewell^1,*, Gowrishankar Srinivasan¹, Eric Cochran²

Journal of Renewable Materials, Vol.2, No.3, pp. 157-165, 2014, DOI:10.7569/JRM.2014.634112

Abstract Presented in this study is a novel recycling strategy for poly(lactic acid) (PLA) in which the depolymerization is rapidly promoted by the base-catalyzed hydrol-/alcohol-ysis of the terminal ester bonds under mild conditions. Post-consumer PLA water bottles were cut into approximately 6 x 2 mm plastic chips and heated to 50–60o C in water, ethanol, or methanol as the depolymerization medium. A variety of carbonate salts and alkaline metal oxides were screened as potential catalysts. High-power ultrasound was also investigated as a means to accelerate the PLA decomposition. Both mass loss and HPLC analysis of the treated suspensions showed that the… More >

Jintao Liu¹, Juan Zhao¹, Xiaowei Shen^1,2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.134, No.2, pp. 981-1003, 2023, DOI:10.32604/cmes.2022.021641

Abstract In this work, an acoustic topology optimization method for structural surface design covered by porous materials is proposed. The analysis of acoustic problems is performed using the isogeometric boundary element method. Taking the element density of porous materials as the design variable, the volume of porous materials as the constraint, and the minimum sound pressure or maximum scattered sound power as the design goal, the topology optimization is carried out by solid isotropic material with penalization (SIMP) method. To get a limpid 0–1 distribution, a smoothing Heaviside-like function is proposed. To obtain the gradient value of the objective function, a… More >

T. Manikandan¹, S. Karthikeyan^2,*, J. Jai Jaganath Babu³, G. Babu⁴

Intelligent Automation & Soft Computing, Vol.35, No.3, pp. 2755-2771, 2023, DOI:10.32604/iasc.2023.030497

Abstract Signal to noise ratio in ultrasound medical images captured through the digital camera is poorer, resulting in an inaccurate diagnosis. As a result, it needs an efficient despeckling method for ultrasound images in clinical practice and telemedicine. This article proposes a novel adaptive fuzzy filter based on the directionality and translation invariant property of the Non-Sub sampled Contour-let Transform (NSCT). Since speckle-noise causes fuzziness in ultrasound images, fuzzy logic may be a straightforward technique to derive the output from the noisy images. This filtering method comprises detection and filtering stages. First, image regions classify at the detection stage by applying… More >

Sajad Zare^1,2, Abdolrasoul Rahmani³, Javad Korouzhdeh⁴, Masoud Hajghani⁵, Rouhollah Rostami⁶, Reza Esmaeili^7,*

Sound & Vibration, Vol.56, No.3, pp. 275-291, 2022, DOI:10.32604/sv.2022.020207

Abstract Noise pollution is one of the most significant harmful physical factors in the industrial and occupational environments. Due to the high costs of exposure to excessive noise; continuous sound evaluation, propose and implement noise control plans in occupational environments is necessary. Thus, the present study aimed to review environmental sound measurements, drawing of noise maps, and prioritizing the engineering noise control methods using the Analytic Hierarchy Process (AHP). This study was a descriptive-analytical study that aimed to assess occupational noises and present a control plan in the City Gas Stations (CGSs) of Kerman, Iran in 2021. The present study was… More >

Jacob Thottathil Varghese^1,2,*, Sajan Thomas^1,2,3, Joselin Herbert⁴, Chacko Preno Koshy^1,2, Arjun Venugopal^1,2

Sound & Vibration, Vol.56, No.3, pp. 255-274, 2022, DOI:10.32604/sv.2022.016180

Abstract The arrangement of natural and physical features on the earth’s surface are a few among the countless items that govern the airborne acoustic transmission at boundary layers. In particular, if the acoustic waves are attributes of live concerts at open-air theatres, without losing the sheen and quality, the audience should certainly receive the unbroken depth of the performance. Hence, at all times, it is advisable to analyse the auditory receptiveness, particularly in all intended recreational spaces. The current pandemic circumstances and the mandated COVID-19 prevention protocols encourage gatherings in naturally ventilated outdoor regions than confined indoors. This work predicts and… More >

Sukhbir Shahid^*

Sound & Vibration, Vol.56, No.3, pp. 245-253, 2022, DOI:10.32604/sv.2022.016139

Abstract The potential use of sound and vibration for diagnostic and therapeutic purposes remains largely under-explored and under-estimated. Sound and vibrational energy has great positive impact on the mind and body. It could be particularly useful for psychosomatic diseases as a complementary therapy. Singing bowls, the spiritual ancient therapy has been claimed to aid in mind relaxation and painful and inflammatory conditions. Childhood asthma is an inflammatory airway disease and a psychosomatic disorder. The psychological management in it is often neglected leading to under-treatment or a relapse. Hence, we hypothesized that sound therapy with singing bowls might be useful as complementary… More >

Srilekha Muthukaruppankaruppiah^1,*, Shanker Rajendiran Nagalingam², Priya Murugasen³, Rajesh Nandaamarnath⁴

Intelligent Automation & Soft Computing, Vol.35, No.2, pp. 2309-2323, 2023, DOI:10.32604/iasc.2023.029598

Abstract Malfunction of human liver happens due to non-alcoholic fatty liver. Fatty liver measurement is used for grading hepatic steatosis, fibrosis and cirrhosis. The various imaging techniques for measuring fatty liver are Magnetic Resonance Imaging, Ultrasound and Computed Tomography. Imaging modalities lead to the exposure of harmful radiation of electromagnetic waves because of frequent measurement. The continuous monitoring of fatty liver is never achieved through imaging techniques. In this paper, the human fatty liver measured through a Fatty Liver Sensor (FLS). The continuous monitoring of the fatty liver is achieved through the FLS. FLS is fabricated through the screen-printing with materials… More >

G. Karthiha^*, Dr. S. Allwin

Intelligent Automation & Soft Computing, Vol.35, No.2, pp. 1753-1765, 2023, DOI:10.32604/iasc.2023.022631

Abstract In spite of the advancement in computerized imaging, many image modalities produce images with commotion influencing both the visual quality and upsetting quantitative image analysis. In this way, the research in the zone of image denoising is very dynamic. Among an extraordinary assortment of image restoration and denoising techniques the neural network system-based noise suppression is a basic and productive methodology. In this paper, Bilateral Filter (BF) based Modular Neural Networks (MNN) has been utilized for speckle noise suppression in the ultrasound image. Initial step the BF filter is used to filter the input image. From the output of BF,… More >

Si Chen¹, Yuhao Zhou¹, Sarah Mohrmann², Haiyan Fu¹, Yuying Zou¹, Zheng Wang^1,*

Journal of Renewable Materials, Vol.10, No.11, pp. 2791-2803, 2022, DOI:10.32604/jrm.2022.021531

Abstract Based on the efficient sound absorption characteristics of Helmholtz resonance structures in the range of medium and low frequency acoustic waves, this paper investigates an effective solution for light timber construction walls with acoustic problems. This study takes the light timber construction wall structure as the research object. Based on the Helmholtz resonance principle, the structure design of the wall unit, impedance tube experiment and COMSOL MULTIPHYSICS simulation calculation were carried out to obtain the change rule of acoustic performance of the Helmholtz resonance wall unit structure. The research results show that the overall stability of sound insulation of the… More > Graphic Abstract

Ziyi Wang¹, Xiaoyan Zhao^1,*, Hongjun Rong¹, Ying Tong¹, Jingang Shi²

Journal of New Media, Vol.4, No.3, pp. 145-153, 2022, DOI:10.32604/jnm.2022.030178

Abstract Microphone array-based sound source localization (SSL) is widely used in a variety of occasions such as video conferencing, robotic hearing, speech enhancement, speech recognition and so on. The traditional SSL methods cannot achieve satisfactory performance in adverse noisy and reverberant environments. In order to improve localization performance, a novel SSL algorithm using convolutional residual network (CRN) is proposed in this paper. The spatial features including time difference of arrivals (TDOAs) between microphone pairs and steered response power-phase transform (SRP-PHAT) spatial spectrum are extracted in each Gammatone sub-band. The spatial features of different sub-bands with a frame are combine into a… More >