bluuebunny/crossref_metadata_2025 huggingface dataset:
Demographic, Behavioural, and Biological Factors Seen in Men Who Have Sex with Men with Salmonella spp.: A Systematic Review
Authors: Sivachandran Vidhushan , Wahab Natasha , Dubey Vaibhav , Richardson Daniel , Llewellyn Carrie
Published: October 2024

Background: The sexual transmissibility of enteric pathogens, including Salmonella spp., has been described in men who have sex with men (MSM). However, the factors seen in MSM with Salmonella spp. are poorly understood. Method: We aimed to systematically review the literature to explore any factors seen in MSM with Salmonella spp. (MSM). We searched six databases—Medline, PubMed, CINAHL, Embase, Emcare, and Global Health—in April 2024 for manuscripts which contained primary peer-reviewed data in English and the measurement of any risk factors observed in MSM with Salmonella spp. This review was registered on PROSPERO (CRD42023472864). Results: Eleven manuscripts were included in the final review and highlighted demographic (living with HIV), behavioural (oral–anal sex, receptive and penetrative anal sex, hand licking to stimulate their partner, group sex, non-condom use), and biological (co-infection with CMV, Mycobacterium avium complex, Strongyloides stercoralis, Blastocystis hominis, Klebsiella spp. Herpes simplex virus, Cytomegalovirus, Cryptosporidium, Histoplasmosis, Shigella spp.; previous infection with Treponema pallidum, Neisseria gonorhoeae, Chlamydia trachomatis and hepatitis B; and antimicrobial treatment failure) factors seen in MSM with Salmonella spp. Conclusion: Despite a limited number of manuscripts and individuals, this review highlighted some potential demographic, behavioural, and biological factors implicated in the transmission of Salmonella spp. in MSM. These data will provide insights for future guidelines, public health control strategies, and research.
Optimization of Copper-Ammonia-Sulfate Electrolyte for Maximizing Cu(I):Cu(II) Ratio Using pH and Copper Solubility
Authors: Ali Zulqarnain Ahmad , Werner Joshua M.
Published: October 2024

An investigation has been carried out to understand the solution chemistry of the Cu-NH−-SO4−2 system, focusing on the effect of pH on the solubility of copper in the solution and maximizing the Cu(I):Cu(II) ratio. A Pourbaix diagram for the Cu-N-S system has also been created using the HSC Chemistry software for a wide range of Cu-NH3 species, unlike most other studies that focused only on Cu(NH3)42+ and Cu(NH3)52+ (Cu(II)) as the dominant species. The Pourbaix diagram demonstrated that the Cu(I) exists as Cu(NH3)2+, while the Cu(II) species are present in the system as Cu(NH3)42+ and Cu(NH3)52+, depending upon the Eh and pH of the solution. Copper precipitation was observed in the electrolyte at pH values less than 8.0, and the precipitation behavior increased as the pH became acidic. The highest Cu(I):Cu(II) ratio was observed at higher pH values of 10.05 due to the higher solubility of copper at higher alkaline pH. The maximum Cu(II) concentration can be achieved at 4.0 M NH4OH and 0.76 M (NH4)2SO4. In the case of low pH, the highest Cu(I):Cu(II) ratio obtained was 0.91 against the 4.0 M and 0.25 M concentrations of NH4OH and (NH4)2SO4, respectively. Meanwhile, at high pH, the maximum Cu(I):Cu(II) ratio was 15.11 against the 0.25 M (NH4)2SO4 and 4.0 M NH4OH. Furthermore, the low pH experiments showed the equilibrium constant (K) K < 1, and the high pH experiments demonstrated K > 1, which justified the lower and higher copper concentrations in the solution, respectively.
Sound absorption metamaterials designed by machine learning and their applications
Authors: LI Zhi-Han , YU Yonghua , HUANG Weichun
Published: October 2024

Acoustic metamaterials are artificial materials composed of acoustic functional elements along the spatial order, which have extraordinary acoustic properties that are not possessed by homogeneous materials. Since the conception of phononic crystal in the 1990s, acoustic metamaterials
have gradually matured, which prospects industrial application. In our report, we present an acoustic metamaterial design method based on deep learning for sound absorption. The design method is firstly set up with the array of Fabry-Perot resonators, then adapted for the array of Helmholtz
resonators. The method uses a tandem inverse design model based on the convolution neural network(CNN), which is capable of on-demand design. It can generate acoustic metamaterial design of high absorption in targeted frequency range. Three designs of acoustic metamaterials for different purposes
are presented. Firstly, sound absorption metamaterials with selective bandwidth absorption, are used to control tonal noise from electric transformers. Secondly, metamaterials with broadband absorption are used in vehicle cabin noise control. Lastly, full-band near-perfect absorption materials
are created to construct acoustic anechoic chambers.
Impact of road noise components (rolling/propulsion) by vehicle categories (light-duty, heavy-duty and two-wheeled vehicles) on population's noise exposure and associated adverse health effects
Authors: PERNA Maxime , MUñOZ Patricio , LOHR François , JANILLON Valérie , VINCENT Bruno
Published: October 2024

Exposure to road traffic noise can lead to various adverse health effects, ranging from annoyance and night-time sleep disturbances to ischemic heart diseases. The aim of this paper is to identify the contribution of the road noise components (rolling/propulsion) for each vehicle category
(light-duty, heavy-duty and two-wheeled vehicles) on population's noise exposure and the associated adverse health effects. This analysis focuses on the case study of Lyon, France. The input data align with the requirements of the 4th deadline of Directive 2002/49/CE and adhere to the CNOSSOS
calculation standard. The results reveal that the rolling noise component of light-duty vehicles is predominant due to vehicle speed and traffic volume. It is the sole noise component (i) significantly exposing a portion of the population to Lden > 68 dBA, noise limit set by the French
decree of April 4, 2006, and (ii) where over half of the population is exposed to Lden > 53 dBA, recommended threshold by the World Health Organization (2018). By using transfer functions established between noise components for each vehicle category, and population's noise exposure, noise
source-abatement solutions can be quantified in terms of their impact on population's noise exposure, thus determining the reduction in health impacts.
Survey on acoustic preferences in Korean music practice spaces
Authors: KIM Youngsun , KIM Mina , OH Jiyoung , JEONG JeongHo
Published: October 2024

.In 2021, the acoustic quality criteria for music practice rooms was standardized as ISO 23591. This standard will be very useful in constructing and utilizing music education facilities to train excellent music players. "Gugak," Korea's traditional music, is taught and related
performers are trained at major national educational institutions. Recently, a variety of Korean music content has been introduced internationally. The Korean traditional music practice room is used similarly to a general music practice room. However, the acoustic characteristics of traditional
houses where Korean traditional music is played do not have a long reverberation time and are flat across frequency bands, so we investigated what acoustic characteristics actual Korean traditional music players prefer as a practice space. The room acoustic characteristics of Korean music
practice spaces at Seoul National University were measured, and a preference survey was conducted on professional performers who actually use the practice spaces. In the future, we plan to investigate preferences for Korean traditional music practice spaces using real-time sound audibility
technology.
A preliminary analysis of long-term self-reported sleep disturbance attributed to wind turbines and modelled outdoor nightly average wind turbine sound pressure level
Authors: MICHAUD David , GUAY Mireille , KEITH Stephen , DENNING Allison , MCNAMEE James
Published: October 2024

The World Health Organization (WHO) Environmental Noise Guidelines provide source-based annual average nighttime sound pressure level (Lnight) recommendations. For non-aircraft sources the recommendation for self-reported high sleep disturbance (HSD) is the Lnight associated with an
absolute prevalence of 3%HSD. The Guideline Development Group (GDG) reported that no Lnight recommendation could be provided for wind turbines because the evidence available was inadequate. In the current study, outdoor wind turbine Lnight at each dwelling was calculated following international
standards. Questionnaires were completed between May and September 2013 by individuals aged 18-79y (606 males, 632 females), randomly selected from households 0.25 to 11.22 kilometers from operational wind turbines. Calculated Lnight ranged from <25 dB(A) to 46 dB(A). When the source of
sleep disturbance was unspecified, the mean prevalence of HSD was 13.3% overall and unrelated to Lnight (p = 0.53). As Lnight increased, the prevalence of identifying wind turbines as one of the causes of sleep disturbance increased from 0% below 25 dB(A) to 3.8% (95% CI 1.9% to 7.4%) between
40-46 dB(A) (p = 0.01) . The WHO's 3%HSD threshold was estimated to occur for wind turbine Lnight between 38-39 dB(A).
Analysis of a brake squeal functional model using a linear parameter varying perspective
Authors: MALACRIDA ALVES Guilherme , BALMES Etienne , MARTIN Guillaume
Published: October 2024

Brake squeal is a limit cycle vibration induced by mode coupling instability that depends on operating conditions such as applied pressure, temperature, and disc velocity. This work proposes a simplified functional model of brake squeal that reproduces the main characteristics observed
in a full-scale industrial test campaign: vibration growth, limit cycle saturation, vibration decay and parametric dependence. The proposed functional model differs from the well-known Hoffmann model by the introduction of a nonlinear contact law and a quasi-static pressure loading. First,
using a harmonic balance perspective, non-linear forces are shown to lead to a pressure and amplitude dependent contact stiffness. This Linear Parameter Varying perspective allows complex mode computations in the pressure/amplitude domain which are then correlated with a series of transient
responses of the nonlinear modes for three different pressure profiles. The chosen profiles represent usual experiments: drag where a constant pressure is applied, pressure ramps and pressure oscillations mimicking the effect of wheel spin on the contact surfaces.
Noise modeling of UAM around the urban vertiport
Authors: LEE Seung-Min , WIE Seong-Yong , HAAN Chan-Hoon
Published: October 2024

The present study aims to investigate the noise distribution around urban vertiport caused by UAM(Multicopter) and helicopter. Noise modelings were carried out using SoundPLAN software at the some vertiports in Seoul, Korea. Sound source model of UAM and helicopter were used as a form
of hemisphere. Noise predictions were undertaken with three different operations including depart, level flight and landing. In order to evaluate the noise impact on the buildings around the vertiport, noise levels at the outer wall of nearby buildings were calculated as the three noise units
including Leq, Lmax and Lden. Also, noise maps were drawn around the vertiport. As a result, it was found that average noise level of UAM is approximately 12 dB lower than the helicopter noise levels. Regarding the noise frequency distribution, most high noises are made at the mid-frequencies
during landing hours while low frequency noise level around 63 Hz was dominant at take-off time.
A vibration-based method to estimate the low-wavenumber wall pressure field in a turbulent boundary layer
Authors: ABTAHI Hesam , KARIMI Mahmoud , MAXIT Laurent
Published: October 2024

When an elastic structure is excited by a low-speed turbulent flow, it generates flow-induced vibration which is primarily due to the low-wavenumber components of the wall pressure field (WPF) beneath the turbulent boundary layer (TBL). Therefore, to accurately predict the vibration
response of the structure, an accurate estimation of the low-wavenumber WPF is needed. While existing TBL models for WPF well predict the convective region, they exhibit significant discrepancies in predicting the low-wavenumber levels. This numerical study aims to explore the feasibility
of estimation of the low-wavenumber WPF by analysing vibration data obtained from a structure excited by a TBL. An inverse method is proposed based on the relationship between the TBL forcing function and structural vibrations in the wavenumber domain. The random TBL force is simulated with
deterministic loading using the uncorrelated wall plane wave technique. A model of a simply supported plate under a TBL excitation is developed to demonstrate the proposed method. The plate's acceleration data is then used to estimate the WPF in the low-wavenumber range. It is shown how using
multiple discrete frequencies in the analysis can reduce the required snapshots for accurate estimation of the WPF.
Experimental study on the acoustic properties of monofilament fabrics
Authors: WANG Fang , GAI Xiaoling , GUAN Xiwen , XING Tuo , LI Xianhui
Published: October 2024

The traditional machining perforated sound absorption structure has high processing cost and inconvenient installation and disassembly, so that how to efficiently and economically manufacture submillimeter micropores still remains a challenge. In this study, a kind of flexible microporous
sound absorbing material was obtained by weaving a polymer artificial fiber covered with ethylene polyester fiber, and the relationship between the sound absorption performance of the curtain and the porosity of the pass and fabric was obtained through the finite element simulation model and
impedance tube experiment. The mechanism parameters of wide-band flexible microporous material with high sound absorption performance are obtained, which guide the design of a kind of sound absorption material with lower production cost and easy installation and disassembly.
Deep subwavelength sound absorption by a buckling plate resonator
Authors: LI Xianhui , XING Tuo , HAN Erjing
Published: October 2024

Conventional sound-absorbing materials face great difficulties in achieving deep subwavelength broadband sound absorption due to the causal constraint on the minimum thickness. A buckling plate resonator is proposed to alleviate the causal constraint on the thickness of sound-absorbing
materials. The resonator consists of a back cavity sealed by an elastic circular thin plate. When the plate is subjected to a uniform in-plane compressive force up to its critical load, it buckles and behaves as a negative stiffness spring. The positive stiffness of the back cavity is counteracted
by the negative stiffness of the buckling plate, resulting in resonance absorption at the deep subwavelength scale. The sound absorption performance of the buckling plate resonator under different in-plane loads was measured in an impedance tube. Quasi-perfect sound absorption was observed
in a buckling plate resonator with a thickness less than 1% of the wavelength corresponding to the resonance frequency. This work provides a solution for the design of ultra-thin broadband sound absorbers.
Assessing indoor and outdoor noise quality and associated health impacts at selected schools in Surat, India
Authors: SHUKLA Avnish , CHAUDHARY Bhanu , TANDEL Bhaven
Published: October 2024

An optimal ambient environment is crucial for healthy development, yet the excess of vehicles and inadequately planned educational infrastructures compromise cognitive growth in children. This study evaluates the impact of ambient noise on student cognition in five schools situated
along city arterial and sub-arterial roads. A total of 717 students from grades 7, 8, 9, and 11 participated. Noise levels were measured in prevailing noisy conditions (PC) and controlled silence conditions (SC) within classrooms using the Kimo dB300 sound level meter. The observed differences
in noise levels between PC and SC varied across grades, showing reductions of 4.7 ± 3.5 dB, 6.1 ± 0.7 dB, 6.7 ± 1.3 dB, and 4.4 ± 3.46 dB for grades 7, 8, 9, and 11, respectively. Statistical analyses revealed significant differences in the average noise levels
under both conditions. Furthermore, cognitive task performance in PC and SC was significantly different, as evidenced by paired t-tests in tasks such as multiplication, word formation, reasoning, and sentence construction. Dimension reduction techniques identified room acoustics, task difficulty,
speech intelligibility, mental deficiency, and annoyance as critical factors affecting learning abilities. Teachers reported that major impacts of noise include annoyance, sleeplessness, headache, and hearing impairment.
The future of airport noise: a comprehensive analysis of population exposure at Dublin airport 2023 to 2030
Authors: EINICKE Karina , JOHN Kennedy
Published: October 2024

There are conflicting trends in the impact of aircraft noise as increased air traffic is offset by advancements in low noise aircraft technology. This paper considers the case of Dublin Airport and projects the noise impact of operations over the timeline to 2030. The airport projects
an (Average Annual Growth Rate) of 1.2 %, translating to an estimated rise in annual air traffic movements from over 212736 flights in 2023 to around 244635 flights in 2030. This estimated increase poses not only logistical challenges for airports but also an escalation in noise pollution
in the surrounding areas. The most significant challenge in predicting future airport noise exposure lies in the shifts in aircraft fleet distribution and the adoption of technology in newer generations of aircraft. This paper evaluates the most likely combination of fleet distribution and
technology uptake. In 2023, the noise footprint is projected to affect a population of approximately 105762 people with Lden ≥ 55 dB. By 2030, this exposure increases to 168267 people. The increase in air traffic numbers also leads to a notable increase in nighttime flights, bringing nighttime
noise exposure Ln ≥ 50 dB from 127720 in 2023 to 189376 in 2030.
Characterization of the acoustic attenuation index of perforated plasterboard ceilings and lining wall and comparison with an empirical model
Authors: TIZIANEL Julian , DEMANET Cyrille , SIMONEAU Thierry
Published: October 2024

Perforated plasterboards are known for their absorption performance. Measurements of the sound reduction index R is realized with these boards. Two configurations is tested in laboratory, one configuration of a perforated plasterboard ceiling suspended on concrete floor and a second
configuration of perforated plasterboard lining wall fixed on 16cm concrete wall. Following this characterization, a semi-empirical model to estimate the attenuation index is proposed. The perforated board is simulated by considering an heterogeneous board of gypsum and holes related by the
perforation rate. The prediction model is compared with the measurement with a good accuracy. Finally, after extrapolations of sound reduction index is proposed for other perforation rates.
A numerical model calibrated by in-situ measurement for predicting the underwater radiated noise of an azimuth thruster structure of a passenger ship
Authors: DASI Benoit , AUCEJO Mathieu , BRANCHEREAU Sylvain , GROUARD Guillaume
Published: October 2024

In a global context of limiting the impact of noise pollution on the behavior of marine fauna, the understanding of acoustic radiation phenomena from underwater sound sources of a passenger ship is of primary importance. Although diesel engines and propellers are considered to be ones
of the main sources of ship noise, our observations have shown that immersed motors contribute significantly to the noise radiated into the water by passenger ships at low speeds. This contribution summarizes a semi-empirical method for estimating the noise radiated into the water from an
azimuth thruster-type structure. An analysis of the vibroacoustic behavior in water of the structure excited by an internal acoustic source is detailed. Beyond the complexity of performing full-scale measurements in a noisy environment, the analysis of the measurements allows to estimate the
vibration modes of the immersed structure. A numerical model of the dedicated structure, calibrated on the basis of an experimental modal analysis, is used to estimate the pressure field radiated by the structure into the water. As a result of these analyses, a simplified model of radiated
noise in the water is developed for use in nominal thruster operation.
Advancing urban noise monitoring: bridging cost and Class 1 accuracy performance in smart city applications
Authors: KUCZYńSKI Jacek , BARWICZ BARTLOMIEJ
Published: October 2024

This paper extends the "Development Of Low-Cost Noise Monitoring Terminals (NMT) Based On MEMS Microphones" from Internoise 2022, introducing a cost-effective solution for urban noise monitoring in smart cities, the Svantek model SV 303. Compliant with Class 1 standards (IEC
61672-1:2013 and IEC 61260-1:2014), this terminal offers a 30 dBA to 130 dB RMS operating range, ideal for urban environments, and ensures Class 1 accuracy. A significant focus of this development is on achieving excellent directional characteristics, crucial for effective "urban noise"
measurements. The terminal also boasts the best environmental performance among our NMTs, operating reliably from -20 °C to 50 °C in diverse urban settings. Equipped with USB 2.0 and UART interfaces, it integrates seamlessly into existing urban monitoring systems, accommodating a wide
range of devices. This adaptability is essential for smart city applications. The paper explores the design, operational parameters, and integration potential of the terminal. By merging high-performance noise monitoring with cost efficiency, the terminal emerges as a key advancement in smart
city noise monitoring, offering a practical solution for accurate, large-scale urban noise evaluation.
Effect of multi-modal input to the perception of sound quality
Authors: HASHIMOTO Takeo , HATANO Shigeko
Published: October 2024

The perception of sound quality of car interior noise is treated. The decisive factor of sound quality is car interior noise itself but our percetion varies also by the symultaneous exposure of seat and steenring wheel vibrations and the moving seanary from the window screen. We have
conducted subjective experiments on the perception of car interior noise unsing car simulator located inside the sound proof room to see the effect of seat and steering wheel vibration and moving sceenary to our perception on sound quality such as pleasantness, booming sensation and powefulness.
As the results, the addition of moving sceenary and seat-floor vibration together with the steering wheel viration have significant effect to our perception of sound quality.
Validation of sound source localization quality in binaural audio synthesis with head-tracking
Authors: JAMBROSIC Kristian , PLANINEC Vedran , HORVAT Marko
Published: October 2024

Binaural synthesis with head tracking has become a highly important tool in creating an auditory experience for users that is as similar as possible to their perception of sound in the real world. This is crucial in many different applications that rely on accurate representation of
real or virtual sound environments, ranging from scientific research to gaming applications. The quality of the binaural synthesis process and the accuracy and naturalness of the produced result depend on numerous factors, ranging from the selection of suitable IMU sensor technology used for
head tracking to the choice of methods for implementing binaural synthesis using generic or individual sets of Head-Related Transfer Functions (HRTF). This is especially significant in Virtual Reality (VR) systems with three or six degrees of freedom that fully immerse the users in the virtual
world through visual and auditory stimuli. This paper presents the authors' experiences in addressing a variety of challenges that arose during the design of such spatial audio systems and the testing of sound source localization quality. Strong emphasis is put on the testing of sound source
localization quality, where the position of the source dynamically changes in relation to the listener.
How sighted people experience the sense of volume? A phenomenal study
Authors: PILLOT Angele , ROMMEL Delphine , DE VIGNEMONT Frédérique , LESCOP Laurent , GENOIST Margot
Published: October 2024

This study aims to provide a phenomenological description of the sense of volume in sighted people. Especially developed by non-sighted people, the sense of volume is an ability to perceive solids and voids by analysing sound reflection. Our recent works have brought it closer to the
human echolocation's ability, but also to a form of spatial hearing based on the analysis of variations in the ambient sound field. In many studies, blindfolded participants were able to detect a surface positioned in front of them. However, there are no studies reporting on the experience
of the sense of volume in sighted people under conditions of ecological perception. Consequently, we carried out commented walks, combined with a micro-phenomenological interview method in an urban environment. By cross-referencing participants' perceptions (wall detection at one metre, typologies'
discrimination of) with feelings they share (acoustic feelings combined with synesthetic tactile feelings), we demonstrated the ability of sighted people to rapidly unveil a functional sense of volume. Several researchers have hypothesized that sighted people may use a form of automated passive
echolocation. In the light of our results, we wonder whether the sense of volume might be a non-conscious factor in an urban atmosphere.
Drone fleet noise impact calculation - a methodology
Authors: LEGRIFFON Ingrid , RUAUD Elise
Published: October 2024

The introduction of drones into an already dense urban infrastructure is expected to have an important impact on the population. The goal of the SESAR MUSE project, " Measuring U-Space Social and Environmental Impact ", is to develop a set of key performance indicators, methods
and tools for the comprehensive and rigorous assessment of the impact of UAM operations on the liveability and quality of life in European cities. One focus domain is drone-generated noise. In the frame of this project, a number of ONERA tools is chained in order to create noise maps, from
scratch, for realistic drone fleet scenarios. Hence, in this paper a methodology is presented where a flight mechanics tool, noise source models, an en-route tool and an open-source urban noise propagation tool are chained, allowing complete freedom with regard to choice and number of drones,
concept of operations and type of urban environment.
Repeatability of perceptual assessments on single cane reeds
Authors: KOEHL Vincent , GAILLARD Amélie , GAZENGEL Bruno , DE QUARTI Matilde , BLONDEL Thomas , NICOLAS Kelig
Published: October 2024

Instruments such as clarinet and saxophone require a single reed to produce sound. Despite numerous perceptual and physical studies about cane reeds, it is still difficult to relate perceptual qualities to physical parameters. However, the perceptual experiments are often carried out
with few subjects that do not repeat the task over time, which calls the reliability of the assessments into question. Some recent results, obtained with 10 experienced musicians that assessed 4 times a panel of 20 reeds, showed that consistent assessments were obtained only at the fourth
repetition and for half of the subjects. An explanation may rely in the experimental conditions as all musicians had to carry out a standard procedure: same reeds, same mouthpiece, same global quality assessment task. The current study aims at evaluating the repeatability of perceptual assessments
by placing the subjects in natural conditions. As he would normally do when opening a box of new reeds, the musician has to evaluate the quality by using his own material and by defining his own assessment task. The robustness of the perceptual judgements is assessed by repeating the operation
10 times.
Design and analysis of acoustic metamaterial sound insulator for noise reduction at multiple frequencies
Authors: LALY Zacharie , MECHEFSKE Christopher , GHINET Sebastian , KONE T. Charly
Published: October 2024

In this paper, a design of an acoustic metamaterial sound insulator based on porous material with embedded multiple Helmholtz resonators is proposed for noise reduction at multiple frequencies. The periodic unit cell of the metamaterial is made of the porous layer with embedded four,
nine, and sixteen different Helmholtz resonators that are arranged in parallel. The cavities of the resonators have the same volume while the parameters of the necks are varied. The sound absorption coefficient and the transmission loss of the metamaterial obtained using finite element method
show four, nine and sixteen resonant peaks that correspond respectively to the number of Helmholtz resonators within the unit cell. When the parameters of the necks and the cavities are identical resulting in identical resonators, the transmission loss and the sound absorption coefficient
show only one resonant peak. The proposed metamaterial can attenuate the noise at four, nine, and sixteen different frequencies by choosing the number of resonators that constitute the unit cell and adjusting the parameters of the necks. It can be used in many engineering applications such
as aerospace for noise attenuation at multiple frequencies.
Sound transmission loss of constrained layer damping composites featuring elastic plates embedded with acoustic black hole
Authors: YUE Wenxuan , WANG Ziyang , ZHOU Yuhao , WANG Bo , MIN Hequn
Published: October 2024

This paper preliminarily investigates the influence of an elastic layer with an acoustic black hole (ABH) on the airborne sound insulation of a constrained layer damping (CLD) composite plate. ABHs represent a continuous impedance reduction in a local area of the structure, achieved
by reducing material thickness. They efficiently dampen structure-borne sound in plate-like structures, resulting in excellent airborne sound attenuation performance. In the CLD composite structure, a damping layer is inserted between the elastic layers. This configuration achieves noise reduction
and provides excellent airborne sound attenuation performance. By incorporating an ABH on one side of the elastic layer within the constrained damping composite structure and utilizing the damping layer as the terminal damping material for ABH, we achieve a lightweight structure with outstanding
airborne sound insulation performance. Using finite element numerical calculations, we assess the airborne sound transmission loss of ABHs embedded within the CLD plate. Our analysis compares their transmission losses within the frequency range of 10 to 4000 Hz under normal-incidence and random
incidence acoustic field excitations. While the ABH does not enhance the overall sound isolation performance of the CLD plate, it significantly improves the sound isolation dip at the resonance frequency.
Experimental investigation of the sound absorption characteristics of unconsolidated granular materials
Authors: BADRI Yousif , DODD George , HALL Andrew , SCHMID Gian , CATER John , EMMS Grant
Published: October 2024

In the context of a wider research project investigating the use of Granular Material (GM) within floor and wall structures to increase their sound insulation, this study presents the sound absorption coefficient (SAC) measurements of different thicknesses for a range of GM. A primary
aim has been to extend the understanding of the behaviour of GM layers in absorbing the propagated incident sound wave. Equally important has been an assessment of what GM could be sourced from waste and be acceptable for use in buildings from the point of view of fire insulation, handleability,
economy, etc. Samples of GM were placed in an 88mm diameter vertical impedance tube and SACs measured up to 2kHz. The results show the effect GM's different structure (size and shape), bulk volume, and mechanical characteristics have on the range and value of the SAC. These determine the extent
to which GM could be a replacement for traditional sound absorption materials.
Measurement of the friction law between a wet finger and a glass oscillator: Application to the Cristal Baschet
Authors: COUINEAUX Audrey , ABLITZER Frédéric , GAUTIER François
Published: October 2024

The cristal Baschet is a musical instrument created during the 50's. The produced sound results from vibrations induced by friction between wet fingers and glass rods. Each glass rod is connected to an assembly of threaded shaft and mass, whose dynamic properties determine the frequency
of self-oscillation. In this work, an experimental method is proposed to identify the friction law between a wet finger and the glass, with the aim of achieving more accurate modelling of the sound production mechanism. The normal and tangential forces between the finger and the glass rod
are identified by solving an inverse problem, from in-situ measurements using accelerometers and a high speed camera. Experimental identification of the friction law therefore makes it possible to estimate its variability with parameters such as the quantity of water or the diversity of fingers.
Metagratings for underwater acoustic wavefront manipulation
Authors: KOURCHI Hasna , BERNARD Simon , CHATI Farid , LéON Fernand
Published: October 2024

Metagratings are flat periodic assemblies of small scatterers, engineered to achieve effects such as steering, beamforming, or absorption. They have recently received attention in both electromagnetism and acoustic fields. In this work, we report the design, modeling, and experimental
characterization of metagratings to steer underwater acoustic wavefronts towards anomalous directions (i.e. not classically allowed by Snell-Decartes relationships) with high efficiency (close to 100%). They are build from simple assemblies of small brass cylinders, hold by 3D-printed plastic
supports, and can redirect ultrasonic wavefronts either in reflection mode (when placed in front of a reflective surface like e.g. the water / air interface) or in transmission mode. Furthermore, we demonstrate how metagratings build from an asymmetrical pattern of multiple basic elements
can achieve near perfect asymmetrical transmission: a wavefront incident from side of the structure is fully transmitted, while a similar wavefront incoming from the other side is fully reflected, achieving an acoustic one-way mirror effect. This work combine theoretical analysis, finite element
modeling, and experimentation in water tanks to explore and demonstrate the potential of such metagratings for various applications in underwater acoustics, like communication, noise mitigation, and stealth.
FEM simulation of vibrations in building: from volume to shell elements
Authors: LETHUILLIER Tony , GILLOT Gautier , LAULAGNET Bernard
Published: October 2024

The problem of vibrations in buildings situated in the proximity of railway tracks is a major concern for the resident's comfort. More and more studies focus on this problem using FEM models, with shell elements for the building's walls and floors. However, the validity of this simplification
is never fully justified, and it raises questions concerning the dimensions to apply to the model. The model of a building made of 3D elastic elements is compared to its simplified version made of shell elements. Three geometries with different dimensions are tested to find the one closer
to the reference model. Different shell offsets are also tested. The results show great differences of floor vibration levels, mostly for high frequencies, depending on the dimensions of the geometry and the offset. The shell configuration with the closest results to the reference model is
discussed.
A stable model order reduction scheme for an acoustic finite element model with perfectly matched layers
Authors: CAI Yinshan , VAN OPHEM Sjoerd , DESMET Wim , DECKERS Elke
Published: October 2024

Perfectly matched layers (PMLs) are often used in an exterior acoustic finite element model to simulate the Sommerfeld radiation condition. However, the time-domain model is often too large to efficiently handle the transient simulation due to the frequency-dependent stretching function
and the number of elements needed per wavelength. Krylov subspace-based model order reduction can alleviate this problem by only matching the important moments of the original model. However, stability-preservation is not guaranteed, which is the key to perform time-domain simulation. This
work proposes a stability-preserving model order reduction scheme for the time-domain PMLs. By assessing the stability conditions of time-domain PMLs, a two-step strategy is applied. Firstly, a one-sided split basis is used to preserve the form of Lyapunov function of the original model such
that a stable intermediate reduced order model (ROM) results. Secondly, an unsplit basis is applied on the modal transformation of this intermediate ROM to reduce the size further. The proposed method is verified by numerical simulations.
Environmental noise reduction by sonic crystals barrier
Authors: QIAO Xiaoru , CHOY Yatsze
Published: October 2024

In order to reduce unpleasant effects on human health in environment, recent research has moved towards low-frequency and broadband noise mitigation. However, traditional noise barriers have several common shortcomings: airflow blocking, inefficient noise reduction, visual obstruction.
Inspired by the classic design of sonic crystals (SCs), the basic C-shaped unit is improved to replace the conventional vertical outdoor barriers with a compact size. This paper explores the acoustic performance of the shadowed-C-shaped SC both numerically and experimentally. The simulation
results show that this novel design can achieve broader band gap in the range below 5000Hz, especially at the resonant frequencies, the transmission coefficients approach to zero. Experiments are carried out with a full-scale model to evaluate the practical application of SC as noise barriers.
It is verified that there is a good performance of insertion loss in broadband which is basically consistent with the simulation results.
Examination of the effect of air gaps on impact sound insulation performance of dry-type double floor system
Authors: CAO Da , AIDA Yu , INOUE Naohisa , SAKUMA Tetsuya
Published: October 2024

The dry-type double floor system is a floor finishing structure widely installed for apartments and offices in Japan. However, after installing the double floor system, it is found that the impact sound insulation performance using a heavy-weight impact source is usually reduced due
to the resonance of the air layer between the floor panels and the concrete slab. To reduce this adverse effect, small air gaps are set between the floor panels and the surrounding walls. In this paper, an experimental study is conducted firstly. A small specimen including particle board,
support legs and air gaps is made to examine the effect of air gaps experimentally. Then, the air gaps are built as a Maxwell model considering that the air gaps act as the orifice of air spring. The theoretical analysis is conducted to explain the mechanism of impact sound insulation of the
double floor system with or without air gaps. Finally, a parametric study is conducted to investigate the effect of air gaps with different dimensions on the impact sound insulation performance of the double floor system.
Radial compensation for sound field control in enclosed space
Authors: REN Yi , HAYASHI Shigetoshi , ELLIOTT Stephen
Published: October 2024

This study proposes a method for sound field control in an enclosed space. In spaces that are acoustically damped, e.g. a room with absorbent walls, the soundfield is often modelled using a complex wavenumber, which is different to that in a free field. Conventional wave-domain methods
fail to control the sound field when the wavenumbers of the target and the reproduced fields are mismatched. In this study, a radial compensation, matching the wavenumbers at a certain radius in the target and the reproduced fields, is proposed. The results show that the proposed method can
achieve a listening area that extends over an entire sphere, whereas the conventional method restricts this to only the control points at the boundary. Alternatively, applying the radial compensation to multiple radii with a least square method can also achieve a spherical control area but
with decreased control accuracy.
Comparative analysis of two liner acoustic impedance characterization techniques
Authors: LAFONT Victor , RONCEN Rémi , DERRé Jérémie , MERCAT Florent
Published: October 2024

This study presents the comparison of two methodologies of small size liner acoustic impedance characterization. The first one is based on a normal incidence broadband acoustic excitation up to 160 dB inside a 30-mm diameter circular tube, and uses the two microphones method, with microphones
flush-mounted inside the waveguide. This bench, called NTMM and developed at Airbus, allows to directly compute the acoustic impedance at the surface of the sample. The second one lies on a measurement inside the B2A wind tunnel at ONERA, where the sample is mounted as one of the vein walls,
leading to a grazing aero-acoustic excitation, up to Mach 0.3 and 155 dB with a broadband excitation. The impedance is then educed by an inverse method. During the MAMBO research project, dedicated samples have been designed and tested with the two benches as well as on the CANNELLE multimodal
test rig developed by Airbus. The full paper will analyze the results and offer a cross comparison of the methodologies, highlighting the advantages and limitations of each approach.
Analysis of in-situ acoustical performance of a removable urban pavement with a porous top layer
Authors: CESBRON Julien , KLEIN Philippe , LELONG Joël , LE BELLEC Adrien , GENNESSEAUX Eric , SEDRAN Thierry
Published: October 2024

A demonstrator of a new removable urban pavement with functionalized surface was implemented in the inner city of Nantes within the I-STREET CUD-SF project. Designed for easy maintenance operation, it is made of hexagonal cement concrete slabs with a dense body and a 4 cm thick porous
top layer of grading 0/6 and porosity 25% for drainability. The noise performance of the pavement was assessed at urban speeds by simultaneous Coast-By and Close-Proximity noise measurements performed with a dedicated test vehicle after closure of the road to traffic. The results are compared
with noise levels obtained with three reference surfaces, a DAC 0/10 and two VTAC of grading 0/4 and 0/6. The tested pavement gets ranked differently depending on the noise measurement method considered. The results are analyzed in the light of 3D texture measurements as well as sound absorption
measurements performed in situ by the extended surface method and with Kundt's tube on core samples. The influence of texture irregularities at the junction between slabs and sand used for slabs stabilization is addressed. Finally, the Coast-By noise levels are compared with those obtained
with the HyRoNE prediction model from 3D texture and sound absorption. The discrepancies observed are discussed.
Aeroacoustic modeling of a low Reynolds number rotor in the wake of a cylindrical beam
Authors: GOJON Romain , VELLA Emma , DOUE Nicolas , PARISOT-DUPUIS Hélène , MELLOT Bertrand , JARDIN Thierry
Published: October 2024

In micro air vehicles, low Reynolds number rotors operating in close proximity to the fuselage raises the question of interaction noise as a prominent acoustic source. This paper proposes to comprehensively explore the interaction noise generation mechanisms, employing numerical simulations,
experimental approaches, and analytical modelling. The focus is on scenarios where a low Reynolds number rotor is located in the wake of a cylindrical beam, and oppositely when the beam is in the wake of the rotor. In both scenarios, it is observed experimentally that the amplitudes of the
BPF harmonics are increased with respect to that obtained without beam. This increase is higher when the rotor is in the wake of the beam compared to when the beam is in the wake of the rotor. The numerical simulation is shown to reproduce quite well the envelope of the amplitudes of the BPF
harmonics obtained experimentally in both scenarios. Interestingly, by applying Ffowcs-Williams and Hawkings analogy on elementary surfaces, and not on the whole rotor-beam surface, the main sound generation mechanism was found to be the unsteady loading on the beam in both scenarios. Finally,
an analytical modeling of the noise source mechanism is compared with experimental and numerical results.
Noise without noise? Art interventions in a Southeast Asian city
Authors: GROTH Sanne Krogh , BUBANDT Nils
Published: October 2024

The experimental music community Jogja Noise Bombing based in the Indonesian city of Yogyakarta has for more than a decade experimented with pop-up performances of harsh noise played on DIY instruments in urban spaces. These urban spaces, however, tend themselves to be very "noisy".
Since 2018 we have followed these performances online and through fieldwork in Indonesia with an ongoing curiosity that stays with the trouble of noise. We are attracted to the context of these performances because they challenge us to answer a series of paradoxical questions: what is noise
aesthetics in a place where everything is "noisy" and where this noisiness, furthermore, does not seem to be experienced as a problem or provocation? Can one even speak of "noise" if it is not unwanted? The social aesthetics of Indonesian harsh noise music in its specific
attunement to the soundscapes of the Indonesian city challenges Western conventional ontologies of noise and ideas of the relationship between "objective" noise and aesthetic performances of noise such as noise music in several ways.
"Projekt TyreRoadNoise" -- Data-based study of effects on controlled and real drive noise emission
Authors: MENG Jiawen , WINANDI Achim , GAUTERIN Frank
Published: October 2024

Road traffic noise affects the quality of life of many citizens. In particular, the noise emitted by electric vehicles is mainly caused by tyre-road contact. There are many conflicts of interest between the performance characteristics of tyres and road surfaces. Therefore, more accurate
prediction models are needed to exploit the potential for reducing tyre-road noise emissions during development. To this end, the TyreRoadNoise project team is developing a physics- and data-based tyre-road noise prediction model over a three-year period. A multi-manufacturer fleet of vehicles
will collect extensive data on tyre-road noise emissions and their influencing parameters using simple measurement methods. AI methods will be used to estimate relevant parameters and correlations, which will be validated by measurements in controlled environments. The model should make it
possible to extrapolate emissions on other routes from appropriate measurements on a specific road and to derive mitigation measures. Data and models will be made publicly available for future use. This article identifies the research needs, gives a brief overview of the project and describes
the tyre-road noise measurement techniques used. Interested parties are invited to discuss and participate in the project.