Head-related transfer function (HRTF) contains all the relevant cues that humans rely on to perceive the direction of a sound source, and its modeling has been widely studied in the past years. Motivated by the different degree of fluctuations in HRTF magnitude spectrum across frequency, in this paper, a mixed-order modeling approach in the spherical harmonic domain is proposed in which HRTF magnitude

Many industrial and consumer applications require their components be activated to achieve the desired functionality. In most of the cases, the activation is produced by gear-motors, which adapt speed and torque to the specifications set forth in the design process stage. On the whole, gear-motors consist of a motor as the main energy source provider and a kinematic chain to transmit and transform

Electrodynamic loudspeakers usually used in active noise cancellation show several limitations due to the difficulty of embedding in complex harsh conditions, e.g. the conditions for active noise control of tonal turbofan noise. Instead, this study presents a Harmonic Acoustic Pneumatic Source (HAPS), designed to generate a controlled harmonic anti-noise from a pneumatic source. It is based on a controlled

In recent years, metamaterial-structures and Microperforated panel (MPP) absorbers have been proposed as a valid alternative to porous materials for sound absorption in the low frequency range. However, high and broadband absorption cannot be achieved in the low frequency range as required in some engineering applications where large thicknesses of the absorbers are unsuitable. In this work, a deep

The sound attenuation of a silencer consisting of a lamella network made with melamine foam inserted in rectangular duct is investigated numerically and experimentally. The lamella arrangement is designed so that skeleton bending elastic resonances appear at low frequency. In addition to this phenomenon, viscothermal losses in the porous material ensure broadband attenuation. The lamella network provides

Liquid sloshing in fuel tanks has become a major source of noise in hybrid vehicles under various driving conditions. Flow dampening devices like baffles proved to be a good solution to control sloshing induced loads on the tank walls. But their effect on sloshing noise is yet to be understood clearly. This study provides insights into generation mechanisms of sloshing noise in a rectangular tank,

In this study, two-dimensional finite-difference time-domain analysis was used to investigate sound transmission loss (STL) of porous materials with different incident angles. This method has provided evidence for the feasibility of measuring STL in situ using one particle velocity–pressure sensor and one pressure sensor. In the numerical analysis, the total sound pressure and the vertical component

Windows are obvious targets for laser eavesdropping and can be easily eavesdropped. However, studies on the window vibration characteristics and associated anti-laser-eavesdropping measures are relatively scarce. To reduce the window vibration and decrease the eavesdropping risk, this study investigates the influence of the glass thickness, glass size, and number of window layers on glass vibration

Ultra-precision diamond cutting finds wide applications in various areas such as freeform optics, micro-structure arrays and high precision molds. Except for process parameters, machined surface quality is also directly influenced by the state of cutting tool edge. In this paper, a novel method for controlling the tool edge by multi-axis ultrasonic vibration is investigated. Kinematic analysis shows

It has been reported that Direction-of-Arrival (DoA) distribution of reflected sounds is not isotropic in late reverberation. However, it is not clear how room characteristics contribute to the anisotropic DoA distribution. In this paper, the relation between DoA distribution in late reverberation and room characteristics is analyzed by using geometrical acoustic simulation and plane wave decomposition

With a wide application of multiphase flow pumps, it is obvious that the flow-induced noise in the transportation of gas–liquid two-phase media is turning more and more into the focus. To study the influence of different inlet gas volume fractions (IGVFs) on the flow-induced noise in a pump, this study focused on the internal flow characteristics and the noise radiation characteristics of acoustic

Language identification (LID) is identifying a language in a given spoken utterance. Language segmentation is equally important as language identification where language boundaries can be spotted in a multi-language utterance. Language identification could be a trivial front-end process for real-time mixed-speech recognition applications. India is a multilingual country and mixing two languages in

Acoustic agglomeration refers to the group effect of micro-particle groups in a strong sound field, which promotes relative motion among the particles, leading to the rapid agglomeration of the particle groups. The existing theoretical and experimental research on acoustic agglomeration is focused on solid particles such as soot particles and aerosols, and the acoustic agglomeration of micron-scale

Double hearing protectors (DHPs), earplugs and earmuffs worn in combination, may be needed in high level noise environments. The DHP sound attenuation is known to be less than the sum of each single protector attenuation. This effect, referred to as the DHP effect, is still not fully understood. A recent study has shown that it can be observed on an acoustic test fixture (ATF) and characterized by

Impulsive noise is widely distributed in various scenarios and becomes an important challenge for the practical applications of active noise control (ANC) system. The conventional ANC algorithms based on the transformation function have a fixed compression level for error signal, leading to slow convergence and weak noise reduction under certain circumstances. To overcome this defect, this paper proposes

Many automated sound-based fault diagnosis or classification methods have been presented in the literature. A novel automatic fault diagnosis method is presented by using sounds for the cooling system of the data center. A novel feature generator and an iterative feature selector are used together to present an automated data center cooling system (DCCS) fault diagnosing method. A new feature generator

This paper explores the feasibility of active control of noise from magnetic resonance imaging (MRI) systems using control sources placed outside of the region that MRI scanners are sensitive to ferrous materials. Active noise control (ANC) is shown here to be equivalent to the time reversal (TR) inverse filter technique with a 180° phase shift. Since TR is capable of remotely focusing sound energy

Room acoustical simulations are usually evaluated by comparing them to measurements in corresponding physical environments as a benchmark. However, it proved to be challenging to provide a precise representation of the room geometry, the source and receiver characteristics, and the absorption and scattering coefficients to be re-modeled in the simulation. We aim to overcome these shortcomings by providing

Conventional delayless subband active noise control (ANC) systems can be degraded by the unexpected impulsive disturbances in the reference signal and/or the residual error signals despite the fact that the step sizes have been normalized by the variances of subband signals. Another inherent drawback is that an undesirable delay is introduced into the weight update path by using analysis filter banks

Birds may need to be identified for purposes such as environmental monitoring, follow-up, and species detection in the ecological area. Automatic sound classifiers have been used to perform species detection. Many methods have been presented in the literature to classify bird sounds with high accuracy. Nowadays, deep learning models have been used to classify data with high classification accuracy

Noise is considered as one of the most influential physical factors in working environments. The advancement of industries has made it a threat to the physical and mental health of individuals on a global scale. Over the past twenty years, there has been strong evidence of a relation between the impact of external factors, lifestyle, and socioeconomic status. The present research aimed to investigate

The head mass as front-end material is an essential component of Tonpilz transducers. The transmission mechanism of head mass under excitations of continuous wave and short pulse are investigated in order to maximize the transducer acoustic radiation power. In the case of continuous wave excitation, it was found that the role of the head mass is to change the effective vibration velocity, and the transmitting

New relations are presented to better evaluate the longitudinal and transverse velocities in porous materials under the dry state, respectively. The models are based on semi analytically derived bulk and shear moduli-porosity correlations for dry porous materials. The accuracy and robustness are validated by fitting the published elastic waves-porosity data of different porous materials and a further

In order to improve the classification performance of ship-radiated noise effectively, a comparative study of four multi-scale entropies is carried out by combining with grey relational degree (GRD) and a novel classification method for ship-radiated noise is proposed based on multi-scale reverse dispersion entropy (MRDE) and GRD, named MRDE-GRD. In this paper, MRDE is applied to the complexity feature

In the process of nonlinear acoustic echo cancellation (NAEC), the eradication of echo becomes challenging due to the nonlinear distortion introduced by the low-cost hands-free communication devices. To mitigate the effect of these artifacts, various NAEC adaptive filtering algorithms are existing which find their applicability in different echoed environments. But, there exists a scope to improve

Attenuation and latency are important performances of earmuff, where the former defines passive noise reduction capability, the latter is a key factor in the design of a feedforward active noise control earmuff. Previously an earmuff lumped parameter model was developed to predict earmuff attenuation. The aim of this work was to predict earmuff latency by using the lumped parameter model (LPM). The

Multi-rotor Unmanned Aerial Vehicles (UAVs) are developing rapidly recently in usage and popularity in civil applications. However, although the great benefits UAVs have brought, their noise pollution is one of the concerns with their proliferation. The two main noise sources of a UAV are the motors and propellers. And the propellers are often assumed to be the dominant noise source in the literature

In this study, the acoustical and vibrational effects of radiating ultrasound waves to the human aorta is investigated. The aortic segment, which is composed of three distinct layers of tunica intima, tunica media and tunica adventitia, is modeled by a thick laminated composite cylindrical shell. The vibro-acoustic response of the aorta, which includes the amplitude of vibration in the longitudinal

The paper predicted the sound reduction indices (SRIs) of plenum windows with various configurations by the surface impedance approach (SIA). Assuming that the glass panes of plenum windows are rigid, two spaces connected through a plenum window can be taken as a three-coupled space. In terms of a multiply connected space, the SIA enables to characterize the acoustical properties of each sub-space

The aeroacoustic wind tunnel at Southern University of Science and Technology (SUSTech) is a new facility commissioned for studies of sound generation mechanisms, noise reduction methods, and aerodynamic designs. The wind tunnel is operated at low Mach numbers and low-to-moderate Reynolds numbers. This study details the design methodology for wind-tunnel major components. The validation tests of the

There are many pure phase methods for designing acoustical holography structures in the known literature. Different methods may have different characteristics and lead to different results, but few researchers put these methods together for comparison. So we have no idea which method should be taken when dealing with a specific optimization case. This paper investigated the characteristics of three

Conventional microphone array implementations aim to lock onto a source with given location and if required, tracking it. It is a challenge to identify the intended source when the location of the source is unknown and interference exists in the same environment. In this study we combine speaker verification and microphone array processing techniques to localize and maximize gain on the intended speaker

International standards ISO 3382-2 and ISO 3382-3 are increasingly applied to determine the room acoustic conditions in open-plan offices because attention to noise control in such workplaces has increased. The precision of those standards in open-plan offices has not been published. The purpose of this study was to determine the precision of ISO 3382-2:2008 and ISO 3382-3:2012 in an open-plan office

In the scenario of UAC(Underwater Acoustic Communication) between the USV(Unmanned Surface Vehicle) and underwater node, the affection originated from sea surface random fluctuation to UAC system stability cannot be neglected due to the small size of hull and the shallow draft, especially when USV is sailing near sea surface. The experimental results indicate that the random fluctuation of the sea

Purpose This work aims to propose a new propeller recognition (propeller type classification) method by using a nonlinear pattern-based sound classification model with high prediction. This model consists of feature generation, feature selection, and classification phases. To test this model, five types of propellers are produced using a 3D printer. These propellers are categorized using number of

The recently proposed fluctuation-based dispersion entropy (FDE) can distinguish various physiological states of biomedical time series, and is usually used in the field of biomedicine. Inspired by the theory of FDE, we redefine FDE and reverse dispersion entropy (RDE), and propose fluctuation-based reverse dispersion entropy (FRDE), which is an improved method of FDE and RDE. As a complexity feature

Ice accretion changes the shape of the airplane aerodynamic surface, resulting in not only the degradation of aerodynamic performance but also the variation of the aeroacoustic characteristics. In order to explore the effect of the ice accretion on the aerodynamic noise, a NACA0012 airfoil with rime ice model on the leading edge was investigated experimentally in an aeroacoustic wind tunnel using far-field

The new digital programmable radar systems allow the development of waveform agility technique that can be reconfigured to work with different kinds of waveforms without the introduction of any hardware modification, and it also extends to the combination of the carrier frequency agility, intra-pulse chirp, and pulse repetition frequency jittering. The challenging recognition problem of waveform-agile

In precision livestock farming, studies show that bird sound can be employed as a biomarker of health condition. One of the most important steps for this purpose is to study the feasibility of using acoustic features as criteria for disease diagnosis. In this research five acoustic features of bird calls were evaluated for determination of bird health condition. Signals were collected from broilers

Success of any commercial Automatic Speech Recognition (ASR) system depends upon availability of its training data. Although, it's performance gets degraded due to absence of enough signal processing characteristics in less resource language corpora. Development of Punjabi Children speech system is one such challenge where zero resource conditions and variabilities in children speech occurs due to

The present study focuses on the investigations on technique for assessing damage progression and localization in concrete structure using acoustic emission (AE) technique. Damage is introduced in a girder-deck system of reinforced concrete (RC) bridge by monotonically applied load in terms of strain in reinforcement, at defined intervals. AE signals emitted at different damage stages are recorded

This paper presents an efficient reduction method for predicting the nonlinear transient and steady state squeal events in mechanical systems subjected to friction-induced vibration and noise. This proposed reduction technique is based on the Double Modal Synthesis (DMS) method that involves the use of a classical Craig & Bampton modal reduction on each substructure considering the interface surfaces

Speech separation in crowded environments is challenging for hearing-impaired listeners. Unfortunately, hearing aids cannot segregate the main speaker from other interferences without knowing to which speaker the listener attends. In this paper, a new robust binaural speech separation system based on a supervised deep neural network (DNN) is introduced to separate attended speaker in different simulated

Denoising a single-channel speech (recorded using one microphone) remains an open problem in many speech-related applications. Recently, supervised deep learning methods are used to denoise the speech signal. This work uses Deep Neural Network (DNN) to learn the Time–Frequency (T-F) mask of the clean speech from its noisy speech features. In general, Ideal Binary Mask (IBM) is used as the binary mask

This paper derives a collaborative control algorithm called generalized collaborative functional link adaptive filter (GCFLAF) for nonlinear active noise control (NANC). The algorithm adopts the collaborative scheme by handling the noise cancellation problem divisionally and parallelly, and working coordinately. It takes the characteristics of different nonlinear components into consideration and handles

Hearing loss is a common issue when people become older, resulting in problems such as depression, risk of dementia, and cognitive decline, among others. Hearing aids are computationally constrained devices that offer the possibility of solving this issue, thus improving people’s quality of life. A typical algorithm that should be implemented in these devices is Voice Activity Detection. In this work

The feedforward hybrid active noise control (HANC) system combines the strengths of the narrowband ANC (NANC) system and the broadband ANC (BANC) system. Taking this advantage into account, this paper applies it to attenuate the vehicle interior noise mixed with narrowband and broadband components. However, in the HANC system, the NANC subsystem and BANC subsystem are fed a common error signal which

Recent evidence suggests that convolutional neural networks (CNNs) can model acoustic scene classification (ASC) with high accuracy. Ensemble classifiers have also shown high accuracy in different machine learning areas. However, little is known about fusion models between CNNs and different ensemble classifiers for ASC. This study presents an enhanced CNN classification model using the late fusion

Three-dimensional (3D) imaging sonars are becoming increasingly important for ocean investigation and exploitation. To date, 3D imaging sonars employ a conventional beamforming technique popularly to reconstruct underwater 3D acoustical images. However, angular resolution of the conventional beamforming is limited, which is usually determined by array aperture. Sidelobe levels of the conventional beamforming

This paper introduces a new adaptive feedback cancellation technique for hearing aid employing robust upper error bound of set membership filtering in the M-estimate function and applied for affine-projection-like algorithm. Additionally a l1 norm based sparsity term is appended in the cost function which takes care of the convergence while estimating feedback path of the hearing aid exhibiting sparse

Prediction of the impact sound insulation of wooden floors requires information of the excitation forces driving the structure. According to earlier research, it is evident, that the impact force generated by the ISO tapping machine on the wooden floors is different than on bare concrete floors. However, only a few measurement results of the force have been shown in the literature. The purpose of our

Nowadays the use of porous polyurethane sponge (PPS) is very common for sound absorption, thanks to its light-weight feature and easy fabrication. However, in many circumstances the traditional PPS has very limited absorption capabilities, due to the slow wave phenomenon and/or to insufficient sub-wavelength sound absorption. In this paper, we propose a composite porous metamaterial (CPM) consisting

As a typical stressed state, uniaxial stress widely exists in the components, such as bolt stress, which requires to be tested in-situ regularly. In this article, the uniaxial stress in-situ measurement using the electromagnetic acoustic transducer (EMAT) shear and longitudinal waves is proposed. To improve the EMATs efficiency and meet the measurement resolution constraints based on Lorentz mechanism

Energy is fundamental for any industrial development and globalization. Due to the demand of energy finding the cheap and environmental friendly commuting is vital. This study deals about how a saddle position affects the performance of the commuter. In regular and sprint cycling, the interaction between the bike and the rider is crucial. The performance of the cyclist depends on the bike setup and

Voice Gender Recognition is a non-trivial task that is extensively studied in the literature, however, when the voice gets surrounded by noises and unconstrained environments, the task becomes more challenging. This paper presents two Self-Attention-based models to deliver an end-to-end voice gender recognition system under unconstrained environments. The first model consists of a stack of six self-attention

Tire/road noise is a dominant source of passenger car noise, especially above 40 km/h. Given the complexity, variety, and contradiction between different mechanisms, it is a severe challenge to reduce this noise. This paper aims to pave the way to design low-noise tires and assist manufacturers based upon scientific insights. In this regard, unlike other research, all predominant mechanisms, including

Cover Song Identification (CSI) is a task in Music Information Retrieval (MIR) that attempts to identify other versions of a song containing different structures, tonalities, and tempos, what brings several challenges to this task. Some of frameworks proposed to identify cover songs were evaluated through the Music Information Retrieval Evaluation eXchange (MIREX) competition that aims to assess algorithms

Bolted connection is an important connection form between composite laminate plate and metal frame structure. The type and location of the connection bolts are of great influence on the structural strength, stiffness and structural vibro-acoustic properties. To achieve the goal of reduction vibration and noise, the bolted connection form optimization of the panel structure is investigated. Bolts stiffness

The utilize of Kaiser effect during acoustic emission testing is a novel approach for computing the amount of stress in the rock, which has been tremendously exploited due to the immense reduction in the cost and time of determining the in-situ stress. Several parameters influence the accuracy of the Kaiser effect. This paper investigates the effect of anisotropy on the Kaiser effect on the rock. For