Xiaoyan Zhao^{1, *}, Shuwen Chen², Lin Zhou³, Ying Chen^{3, 4}

CMC-Computers, Materials & Continua, Vol.64, No.1, pp. 253-271, 2020, DOI:10.32604/cmc.2020.09848 - 20 May 2020

Abstract Microphone array-based sound source localization (SSL) is a challenging task in adverse acoustic scenarios. To address this, a novel SSL algorithm based on deep neural network (DNN) using steered response power-phase transform (SRP-PHAT) spatial spectrum as input feature is presented in this paper. Since the SRP-PHAT spatial power spectrum contains spatial location information, it is adopted as the input feature for sound source localization. DNN is exploited to extract the efficient location information from SRP-PHAT spatial power spectrum due to its advantage on extracting high-level features. SRP-PHAT at each steering position within a frame is More >

Rohollah Fallah Madvari¹, Mohammad Reza Monazzam², Mohsen Niknam Sharak³, Mohsen Mosa Farkhani^4,*

Sound & Vibration, Vol.54, No.2, pp. 127-137, 2020, DOI:10.32604/sv.2020.08158 - 09 May 2020

Abstract Honeycomb structures have recently, replaced with conventional homogeneous materials. Given the fact that sandwich panels containing a honeycomb core are able to adjust geometric parameters, including internal angles, they are suitable for acoustic control applications. The main objective of this study was to obtain a transmission loss curve in a specific honeycomb frequency range along with same overall dimensions and weight. In this study, a finite element model (FEM) in ABAQUS software was used to simulate honeycomb panels, evaluate resonant frequencies, and for acoustic analysis. This model was used to obtain acoustic pressure and then… More >

T. Asakura^*, K. Shindo

Sound & Vibration, Vol.54, No.2, pp. 85-98, 2020, DOI:10.32604/sv.2020.08119 - 09 May 2020

Abstract A number of studies have been conducted on the improvement of the sound quality of electrical artificial laryngeal speech, the speech produced has been difficult to hear compared to a natural voice. For this reason, it is necessary to effectively improve the frequency characteristics of the input signal. In the present study, to improve the sound quality of vocalization using an electrical artifi- cial larynx, first, a comparison of the frequency characteristics between the real and artificial voices was conducted, and three filters that can make the frequency characteristics of the artificial voice closer to More >

Wei Zhao^{1, 2}, Shuai Feng¹, Yadan Wang¹, Yuanguo Wang¹, Zhihui Han¹, Hu Peng^{1, *}

CMES-Computer Modeling in Engineering & Sciences, Vol.123, No.1, pp. 427-440, 2020, DOI:10.32604/cmes.2020.09387 - 01 April 2020

Abstract Frame rate is an important metric for ultrasound imaging systems, and high frame rates (HFR) benefit moving-target imaging. One common way to obtain HFR imaging is to transmit a plane wave. Delay-and-sum (DAS) beamformer is a conventional beamforming algorithm, which is simple and has been widely implemented in clinical application. Fourier beamforming is an alternative method for HFR imaging and has high levels of imaging efficiency, imaging speed, and good temporal dynamic characteristics. Nevertheless, the resolution and contrast performance of HFR imaging based on DAS or Fourier beamforming are insufficient due to the single plane… More >

Vikas S. Hakke¹, Uday D. Bagale¹, Sami Boufi², G. Uday Bhaskar Babu¹, Shirish H. Sonawane^1,*

Journal of Renewable Materials, Vol.8, No.3, pp. 239-250, 2020, DOI:10.32604/jrm.2020.08449 - 01 March 2020

Abstract Starch nanocrystals (SNC) were prepared from maize starch using ultrasound assisted acid hydrolysis. The process takes less time for the generation of SNC, which is advantageous over conventional acid hydrolysis. The synthesized SNC were characterized using X-ray diffraction, dynamic light scattering, zeta potential and transmission electron microscopy (TEM). Particle size and TEM data show that the particles were near to 150 nm, with oval morphology. The SNC with higher surface charge are obtained with this innovative approach as compared to conventional acid hydrolysis. Because of high surface charge and oval like morphology, the SNC performed More >

T. Jayasree^1,*, R. Prem Ananth²

Sound & Vibration, Vol.54, No.1, pp. 57-74, 2020, DOI:10.32604/sv.2020.08573 - 01 March 2020

Abstract Vehicles generate dissimilar sound patterns under different working environments. These generated sound patterns signify the condition of the engines, which in turn is used for diagnosing various faults. In this paper, the sound signals produced by motorcycles are analyzed to locate various faults. The important attributes are extracted from the generated sound signals based on time, frequency and wavelet domains which clearly describe the statistical behavior of the signals. Further, various types of faults are classified using the Extreme Learning Machine (ELM) classifier from the extracted features. Moreover, the improved classification performance is obtained by More >

Parvin Nassiri¹, Sajad Zare^2,*, Mohammad Reza Monazzam¹, Akram Pourbakht³, Rasoul Hemmatjo⁴, Hossein ElahiShirvan²

Sound & Vibration, Vol.54, No.1, pp. 17-25, 2020, DOI:10.32604/sv.2020.08395 - 01 March 2020

Abstract Exposure to noise can lead to anatomical, nonauditory, and auditory impacts. The auditory influence of noise exposure is manifested in the form of Noise-induced hearing loss (NIHL). The current study aimed at present a signal to noise ratio model of otoacoustic emission of rats’ ears in the light of the combined effect of sound pressure level, sound frequency, exposure time, and potassium concentration of the used water. In total, 36 adult male rates, whose age varied from 3 to 4 months and had a weight of 200 ± 50 g, were randomly divided into 12… More >

Naomi N. Vinod¹, Anna S. Nagle², Hameeda A. Naimi¹, Hiren Kolli¹, Derek Sheen¹, Naveen Nandanan¹, Laura R. Carucci³, John E. Speich², Adam P. Klausner^1,4

Canadian Journal of Urology, Vol.26, No.4, pp. 9829-9834, 2019

Abstract Introduction: The aim of this study was to investigate conventional 3D ultrasound and portable BladderScan volume measurements and implement correction factors to ensure accurate volume metrics.
Materials and methods: Healthy participants without urinary urgency were recruited for a prospective hydration study in which three consecutive voids were analyzed for two separate visits. Just before and after voiding, 3D ultrasound and BladderScan volumes were measured. Estimated voided volumes were calculated as the volume immediately prior to void minus any post void residual and were compared to actual voided volumes measured using a graduated container. Percent errors were calculated,… More >

Rachel Wong¹, Mohammed Al‐Omary², David Baker², Neil Spratt^1,2, Andrew Boyle^1,2, Natasha Baker Cert¹, Peter Howe¹, Nicholas Collins²

Congenital Heart Disease, Vol.14, No.4, pp. 638-644, 2019, DOI:10.1111/chd.12763

Abstract Objectives: Improvements in the management of complex congenital heart disease, including those with single ventricle physiology, have resulted in increased survival. As this population ages, the recognition of cognitive impairment is increasingly im‐ portant. At present, little is known about the potential mechanisms of cognitive dys‐ function. In this cross‐sectional study, we aimed to characterize the nature of abnormalities in cerebral blood flow and the relationship to cognitive deficits in adults with single ventricular physiology.
Patients: Ten adults with single ventricular physiology (age 18‐40 years) and 12 age‐ and gender‐matched controls underwent transcranial Doppler ultrasound and ac‐… More >

Alan F. Riley¹, Elena C. Ocampo¹, Joseph Hagan², M. Regina Lantin‐Hermoso¹

Congenital Heart Disease, Vol.14, No.5, pp. 706-712, 2019, DOI:10.1111/chd.12774

Abstract Background: When performed by cardiologists, hand‐held echocardiography (HHE) can assess ventricular systolic function and valve disease in adults, but its accuracy and utility in congenital heart disease is unknown. In hypoplastic left heart syndrome (HLHS), the echocardiographic detection of depressed right ventricular (RV) systolic function and higher grade tricuspid regurgitation (TR) can identify patients who are at increased risk of morbidity and mortality and who may benefit from additional imaging or medical therapies.
Methods: Children with HLHS after Stage I or II surgical palliation (Norwood or Glenn procedures) were prospectively enrolled. Subjects underwent HHE by a pediatric… More >