bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of thermal-acoustic interaction on comfort under office behaviors - taking air-conditioning noise as an example
Authors: Wen Xin , Meng Qi , Yang Da , Li Mengmeng
Published: December 2023

Thermal-acoustic interaction holds significant importance in the development of subjective perception prediction models. While previous studies on this topic mainly focused on perceptual changes, the differences related to various office behaviors were not fully considered. This study
aims to investigate the effects of thermal-acoustic interaction on comfort during different office behaviors (such as rest, reading, writing, and typing) using air-conditioning noise as an example in a laboratory setting. The results, obtained within the near thermal comfort zone, demonstrate
that: (1) thermal sensation was significantly affected by temperature across all four office behaviors, but thermal comfort was not significantly affected; (2) subjective loudness and acoustic comfort were influenced by temperature during reading, with the lowest scores observed at 23; (3)
sound pressure level significantly affected overall comfort and overall annoyance across all office behaviors, while temperature influenced overall comfort during reading and writing. These findings underscore the importance of effective thermal-acoustic environment adjustments and the establishment
of more accurate and quantitative models for predicting subjective perception. Keywords: Thermal-acoustic interaction, Office behaviors, Comfort, Air-conditioning noise
The study of the acoustic environment of remote work spaces: Characteristics and suitability of work
Authors: Shinkawa Runa , Tsuchida Yoshio
Published: December 2023

In Japan, coworking and remote work spaces have been opened across the country since around 2006. The number of spaces is further increasing as more companies introduce teleworking systems due to the pandemic of COVID-19. Moreover, cafes and restaurants are also increasingly offering
services such as Wi-Fi and power supply. Although the real world is changing and many studies have been done, there are still few studies that focus on multiple forms of remote work spaces. In this study, we focused on the sound environment of remote work spaces, analyzing recorded sound and
investigating the equipment associated with the spaces. The characteristics of each space were clarified by comparing sound pressure levels and type of sound. Based on the results of the analysis, the suitability of each space for work was discussed.
Direct aeroacoustic simulation of a flow through an expanding pipe with orifice plates
Authors: FUKUMA Akitomo , YOKOYAMA Hiroshi , KAWAI Manato , KAWASAKI Kenji , YAMAGIWA Ichiro , NISHIKAWARA Masahito , YANADA Hideki
Published: December 2023

Expanding pipes with orifice plates are utilized as silencers for fluid machinery. However, tonal sounds can be generated from flows through the silencers with such a configuration. To clarify the mechanism of tonal sound generation from a flow over a circular expanding pipe with orifice
plates, flow and acoustic fields were directly solved on the basis of the compressible Navier-Stokes equations. Prediction results demonstrated that tonal sounds occurred at multiple frequencies. The phase-averaged flow fields for each frequency indicated that vortex rings or spiral vortices
were periodically shed in the flow around the orifice plates. Acoustic radiation occurred owing to the collision of these vortices with the orifice plates, which led to the occurrence of acoustic resonance in the expanding pipe. The predicted circumferential phase distributions of pressure
fluctuations demonstrated the coexistence of different acoustic modes in the expanding pipe. The relationship between acoustic modes and vortical behaviors was presented. The effects of inflow Mach number on the vortex structures and acoustic modes for the resonance were also discussed.
Vibration control of a P1 mild hybrid powertrain
Authors: Park Keychun , Han Sanghun , Cho Younghoon , Kim Changwan
Published: December 2023

In hybrid powertrains, the engine excitation induces the vibration issues especially during transients of engine turning on and off as well as steady operating cases with high engine load in low rpm. In this paper, we design an integrated active flywheel with 48V motor to replace alternator
and starter and suggest to cancel out the engine rolling as well as the torsional vibration. The phase based repetitive control law has been employed to control over the higher engine orders in addition to its ease of implementation. First, it is shown in the firing engine bench that both
the torsional vibration and the rolling excitation of engine has been simultaneously reduced with a small fraction of total power consumption. With the combination of the 48V power systems and small modifications, the developed system has been implemented using a mass produced belt type Mild
HEV vehicle and proved to operate successfully in terms of vibration control as well as the Mild HEV functioning.
A metamaterial sandwich plate with spring-lever-mass resonators
Authors: Gao Lei , Mak Cheuk Ming , Cai Chenzhi
Published: December 2023

Sandwich plates are widely used in practical engineering, including civil engineering, transportation, aerospace, and other industrial fields. However, characteristics of high specific stiffness and strength cause poor performance in the vibro-acoustic fields. Therefore, resonators
are introduced into the core of sandwich plates to improve their performance on vibration isolation. This paper proposes a new metamaterial sandwich plate, multiple spring-lever-mass resonators are introduced into the sandwich plate to obtain the low-frequency band gaps. The band structure
of the metamaterial sandwich plate with spring-lever-mass resonators is calculated by the finite element method with the Bloch-Floquet theorem, and the band gap of the unit cell is obtained. The transmission spectra of the proposed structure are investigated to verify the accuracy of prediction
results. The results show that effective performance on low-frequency vibration isolation via the metamaterial sandwich plate with spring-lever-mass resonators can be achieved, and this study can provide valuable references for related research and potential applications on the manipulation
of wave propagation.
The link between noise emission data, product safety and noise risk assessments
Authors: Heisterkamp Fabian , Brockt Georg , Romanus Erik
Published: December 2023

Despite widespread knowledge about noise-induced hearing loss, many workers globally are still exposed to harmful noise levels. The Sell & Buy Quiet concept can address this issue by tackling noise at its source. The EU Machinery Directive 2006/42/EC mandates that manufacturers
provide noise emission data for their machines to inform users about the associated noise risks. Such information promotes safe use of machines and is vital for product safety. Standardized, comparable noise emission data are also crucial for the success of Sell & Buy Quiet. However, more
needs to be done to increase demand for reliable noise emission data and quiet machinery. Reliable noise emission data are required for predicting noise levels in the workspace using sound prediction tools, which can support noise risk assessments and predict the impact of new machines already
at a planning stage.
Latest Development of Low Noise Road Surfacing in Hong Kong - Application on Local Roads with Different Road Characteristics
Authors: CHAN Kei Yuet , LEE Chee Kwan , TSANG Sai Wing
Published: December 2023

Like other metropolitan cities in the world, road traffic noise is a major problem in Hong Kong. The Hong Kong Government endeavors to pre-empt road traffic noise issue through comprehensive noise planning process for new road projects or new residential developments. For traffic noise
from existing roads, the Government has adopted various noise mitigation strategies, for example, resurfacing with Low Noise Road Surface (LNRS) material, retrofitting of noise barrier, etc., to combat the noise problem. As of today, Polymer Modified Friction Course (PMFC) is the most commonly
adopted LNRS in Hong Kong, which serves as a standard road surface material for high-speed roads and expressways. Nonetheless, it is found to be less durable for local roads due to its open-texture, especially for common road characteristics such as frequent start stop, sharp turn, roadside
parking, etc. To explore suitable LNRS material for local roads, a trial programme on a newly developed LNRS material - Polymer Modified Stone Mastic Asphalt (PMSMA6), has been launched to evaluate its noise reduction performance and engineering feasibility on local roads with common road
characteristics. This paper attempts to share the experience and latest technical findings of the above trial programme on LNRS in Hong Kong.
Overview of Onera acoustic active control activities in helicopter cabin
Authors: Simon Frank
Published: December 2023

Within a helicopter cabin, passengers are in close proximity to disturbing sources that contribute to interior noise: main and tail rotors, engines, main gearbox and aerodynamic turbulence. These sources generate bending vibrations of the entire tail boom, induced vibrations in the
cabin at blade passing frequencies, transient vibrations of rotor blades and structure borne noise induced by gear meshing within gearboxes. Conventional passive systems, as trim panels or passive anti-resonance isolation systems, are still the main way to control the cabin noise. Nevertheless,
(semi) active control techniques have been the subject of numerous studies for decades, especially to improve the performance of passive concepts in low frequencies. Unfortunately, many turned out to be unreliable or completely inapplicable because problems of robustness, time convergence
of algorithms, but also a difficult identification of optimal locations for actuators and sensors or a high added mass and electrical power. The objectives of this paper is to describe in details the research projects in active noise control carried out at Onera since the 1990s, i.e. from
numerical modeling and laboratory tests to flight tests in helicopter cabin. This overview will feed into the reflection on the renewal of active vibro-acoustic control within different laboratories.
Assessment of Acoustic performance of classrooms in Ireland
Authors: Heffernan Eoghan , King Eoin A.
Published: December 2023

In recent years the relationship between the quality of the acoustic characteristics of a learning space and the learning process has received increasing attention internationally. It is clear that poor acoustics in school classrooms make them unsuitable for learning tasks that involve
listening. While we now know appropriate values for reverberation time and background noise in classrooms, limited studies have been conducted to assess the performance of Irish classrooms. This paper presents the results of a survey of the acoustic characteristics in primary school classrooms
in Ireland, one of the first of its kind in Ireland. Reverberation times and background noise levels were measured in 30 classrooms, with the data collected used to assess compliance with standards set by the Irish Department of Education. Preliminary results suggest that approximately two-thirds
of Irish classrooms fail to meet the required standard. The results of this survey highlight the need for improvements in the acoustic characteristics of primary school classrooms in Ireland.
Attempt to hold a soundscape contest for young people
Authors: Takano Sayoko , Tsuchida Yoshio
Published: December 2023

Aiming to raise interest in soundscapes, a presentation contest was held for those under the age of 20, including high school students, technical college students, and under second-year university students. The entering began in September and the information about participation was
sent to approximately 150 local high schools. The contest took place on November 14th, with participants giving presentations online and only judges gathering at the venue due to coronavirus concerns. Eight teams participated, including three men's teams and five women's teams. The gold prize
was "Visiting the sound of Kanazawa", showing a video of gold leaf pasting and water harp cave in Higashi-Yama area. Aiming to increase the number of participants next year, we plan to hold workshops on photography and video production in advance.
The effect of thickness and surface roughness on the absorption coefficient (α) of Aluminum (Al)
Authors: Kamil Kusno , Asniawaty  , Said Antarissubhi , Bunawardi Ratriana Said , Aphar Takdir Mutahli
Published: December 2023

Noise is an essential factor in determining various interior elements and machinery, especially those made of metal. The noise level generated by metal is caused by the low level of sound attenuation factor, known as the absorption coefficient (alpha, α) of the metal. Aluminum
(Al) metal has the characteristics of corrosion resistance, lightweight, attractive color, and ease of form, so it is popular as a material for various households, machinery, and industrial machinery. This study explains the effect of surface roughness (0.05, 0.12, and 0.15 Ra) and thickness
(2, 4, and 6 mm) of Al specimens on the measurement values of absorption coefficient (α). The measurements result show that the average value of α is relatively stable by variations in surface roughness and thickness within the low to medium frequency range (200-800 Hz). Although
in general there are increased α values for the high-frequency ranges (1000-1200 Hz), the lowest average of α value occurs in the specimen with the highest surface roughness of Ra 25. Thus, even though the variation in thickness has no significant effect on the α value, the
higher surface roughness of Al will reduce the value of the absorption coefficient (α) resulting in higher noise generated.
FE analysis of porous material covers for automotive parts
Authors: Kurosawa Yoshio , Chengyao Ji , Yamashita Tsuyoshi , Ozaki Tetsuya , Nakaizumi Naoyuki , Fujita Yuki , Takahashi Manabu
Published: December 2023

Some automobile transmissions (AT, CVT, etc.) generate noise, and a soundproof material cover is attached to the transmission body reduce the noise by offering sound absorption and insulation. However, the sound radiating from the cover may affect the transmission of vibrations. In
this study, we attached a simply shaped cover to a jig to represent a transmission body and measured the vibration acceleration and sound pressure level when the jig was vibrated. The jig and cover were modeled by FEM, and vibroacoustic analysis was performed. The material of the cover was
felt or grow wool, and sound propagation was simulated using the Biot-Allard model. This report describes the changes in vibration acceleration and sound pressure level when the method of fixing the cover and cover material are changed.
A small-scale pile impact test for demonstrating the coupling between structural vibration and underwater noise generation
Authors: Vasconcelos Ana Carolina Azevedo , Heijnen Sabine , Holtzer Bart , Aragón Alejandro Marcos , Schott Dingena , Jovanova Jovana
Published: December 2023

The performance improvement of renewable energy sources has become nowadays a crucial topic to boost the energy transition. With respect to offshore wind farms, larger wind turbines are currently being designed to increase their power capacity. To support such turbines into the seabed,
monopile foundations are mainly used, due to their low-cost manufacturing and transportation. Because of the increased wind turbines' dimensions, larger monopiles are needed, which have shown to shift high sound waves to lower-frequency ranges during their installation. A precise prediction
of the high noise level is necessary to properly design noise-cancelling devices, which prevent negative impacts on marine life. Because the evaluation of sound levels at a full-scale monopile installation is time-consuming and expensive, small-scale tests are being explored. Here we propose
a small-scale test for investigating the high noise levels source. To that end, proper scaling laws and instrumentation have been adopted to assure the similarity between the small- and full-scale cases. The experimental results were also compared to a simplified numerical model. The findings
of this work showed that investigating a priori the monopile's features provides an underwater noise prediction, which can be used to design the upcoming noise-cancelling devices.
Estimation of acoustic reflection pattern using multi-point impulse response and spatial Fourier transform
Authors: Hoshika Satoshi , Iwami Takahiro , Omoto Akira , Sugie Satoshi
Published: December 2023

We propose a method using impulse responses (IRs) measured at multiple points to evaluate the acoustic reflection of materials. This method combines responses with appropriate delays and estimates the reflection patterns of arbitrary incident waves. IRs are measured for all combinations
of sources and receivers, which are arranged in a grid pattern on planes. Further, postprocessing can estimate the directions of the incident and reflected waves. This is equivalent to synthesizing a wavefront using the sound field reproduction technology. Direction-of-arrival (DOA) estimation
was performed by applying a spatial Fourier transform to the processed sound pressure. Numerical simulations were conducted for plane-wave incident conditions using impulse responses generated by the mirror-image method, assuming that the material surface is rigid. The numerical results demonstrate
that the proposed method can accurately estimate the reflection pattern when a plane wave arrives in an arbitrary direction. However, as the incident angle becomes almost parallel to the material surface, that is, at grazing incidence, synthesizing wavefronts with sufficient accuracy becomes
more challenging.
Sound absorption performance analysis of perforated panel resonator with tube bundles based on independent adjustment impedance
Authors: Mei Zhongjian , Yang Huawei , Li Xiaodong , Lyu Yadong , Jun Yang
Published: December 2023

A method of independent adjustment of acoustic resistance and acoustic reactance is proposed for the problem of coupling of acoustic resistance and acoustic resistance affecting impedance matching in sound resonant absorbers. Combining theoretical analysis model and finite element simulation
model, the modulation mechanism of independent adjustment impedance is revealed. Theoretical and simulation results show that for the same structural thickness and perforation rate, the acoustic resistance of the perforated panel resonator with tube bundles (PPTB) varies with the inner diameter
of the tube, but the acoustic resistance remains constant. The PPTB can exhibit different damping states at the same resonant frequency and show different sound absorption performances. The experiment verifies that independent adjustment impedance can improve the impedance matching effect
and enhance the sound absorption performance. In addition, the influence of structural parameters on the sound impedance is discussed. Moreover, independent adjustment impedance can be expected to design low-frequency broadband sound absorption structures and optimize sound absorption bandwidth.
Designing decision-making support algorithms for noise and vibration in digital environmental impact assessment
Authors: Kim Kyoungmin , Lee Byungkwon , Park Taeho , Park Young Min , An Junyeong , Jeon Hyungjin , Sun Hyosung
Published: December 2023

The Republic of Korea has implemented a policy to objectively predict and evaluate the environmental impact of development projects over a five-year period from 2020 to 2024. This is achieved through AI-based data analysis and the results are visualized in three dimensions to support
decision making. The aim of this policy is to improve the reliability and transparency of environmental impact assessment and contribute to sustainable land environment management by integrating ICT (Information and Communications Technology). To this end, this study proposes an algorithm
for web based digital environmental impact assessment and decision making support. The algorithm is targeted towards noise and vibration items in the living environment field during environmental impact assessment. It is designed for each project type and major process (current status survey,
construction, operation, post-environmental impact survey, etc.), and can be implemented in a user interface (UI) such as visualization when introducing digital environmental impact assessment.
Annoyance Prediction of Civil Aircraft Cabin Noise Based on Generalized Additive Models
Authors: Zhang Jun , Chen Kean , Lai Wenhui , Deng Yunyun , Zhao Huanqi
Published: December 2023

Noise in civil aircraft cabin is a major contributor to passenger comfort. It is of great significance to predict the noise annoyance by developing a model. However, the low accuracy of linear model and the poor intelligibility of the neural network are the critical problems to be solved.
Generalized additive models (GAMs) have become a leading choice for explainable machine learning. This study examines the effectiveness of GAMs in noise annoyance prediction. First, the annoyance of the cabin noise was collected through subjective listening test. Subsequently, three physical
acoustic features (sound pressure level, A-weighted sound pressure level, preferred speech interference level) and five psychoacoustic features (loudness, sharpness, roughness, fluctuation strength, tonality) were applied to describe the stimuli. In the third step, three algorithms were used
to construct GAMs based on annoyance (dependent variable) and feature parameters (independent variables), and the prediction accuracy was computed by ten-fold cross-validation. The result indicated that GAMs have higher prediction accuracy than linear regression model. The importance of features
was evaluated, which is more intelligible than the neural network. This study provides the first assessment of GAMs in the annoyance prediction of civil aircraft cabin noise, and the findings may be of assistance to engineering noise control.
A multizone sound field reproduction method based on modal domain analysis
Authors: Wen Xin , Wu Haijun , Fan Yilong , Jiang Weikang
Published: December 2023

Multizone sound field reproduction for synthesizing desired sound fields over multiple spatial zones has been widely studied. In the traditional multizone sound field reproduction modal domain method, the final loudspeaker weights required to reproduce the desired sound field are obtained
by translating the optimal equivalent global modal domain coefficients, which is susceptible to the characteristics and location of the loudspeakers and reduces the reproduction performance. This paper investigates a multizone sound field reproduction in modal domain for directly obtaining
the reproducing loudspeaker weights. The optimization model is formulated to the objective of reproducing a desired sound field within the bright zone and with constraints on acoustic energy in the dark zone. The loudspeaker weights for reproducing the desired sound field are solved by the
CVX toolbox. The numerical simulation results indicate that the proposed method is superior to the acoustic contrast control method and the mode matching method in terms of the accuracy of the reproduction desired sound field in the bright zone and the acoustic contrast between the bright
and dark zones.
Acoustic wave focusing using holographic acoustic metalens and its optimization using gaussian process
Authors: Park Sungjun , Kim Jedo
Published: December 2023

In this study, we present experimental and numerical results of an efficient acoustic focusing apparatus using a series of impedance-varying acoustic metasurfaces. The impedance-varying surfaces are formed by changing the cylindrical intrusions on the metasurface, comprising a pattern
that directs the acoustic beam to a desired angle. We show design parameters that play an important role in the focus points, focal area, and focus efficiency and verify this through experiment and multi-physics simulation approach. In addition, we show the prediction and optimization process
of the acoustic metalens using the Gaussian process.
Soundscape improvement of 45 Danish nursing homes
Authors: Højlund Marie Koldkjær , Dahl Mads Duevang , Lundgård Sissel Raahede
Published: December 2023

This paper describes an analysis of Danish nursing home soundscapes and the subsequent attempt at implementing incremental interventions aiming to improve the soundscapes. Danish nursing homes are challenged by simultaneously being a home, workplace, and institution. Staff and residents
will invariably encounter the conflicting environmental characteristics of these disparate functions, including the sound environment. In 2020, Aarhus Municipality launched a project in collaboration with Aarhus University. In the first phase, the authors conducted a soundscape analysis in
five nursing homes in Aarhus. This resulted in a report containing recommendations for improving the nursing home soundscape. In the second phase initiated in 2022, soundscape screenings in all 45 nursing homes in Aarhus was conducted, the purpose of which was the mapping of existing sound
sources and how staff and residents perceived them. The results of the screenings confirmed the findings in the report with certain local differences. As of May 2023, various soundscape interventions are being tested in several nursing homes. As this process is still ongoing, this paper will
review the results and experiences collected so far. As part of this long-term project, the authors wish to address the gap between soundscape analysis and practical soundscape interventions.
Prediction of Aerodynamic Broadband Noise Generated from a Flat Plate based on Machine Learning
Authors: Sasaki Soichi , Tanaka Kodai , Aramaki Daiki
Published: December 2023

We propose a methodology for the prediction of the broadband noise generated from a flat plate based on the decision tree in the machine learning. First, we developed the wind tunnel with an anechoic room consisting of the sound insulation walls and the sound absorbing materials for
the purpose of its accurate measurement of the aerodynamic noise. The pressure PSD, which is to be the training data, is extracted from the measured broadband noise in the wind tunnel test, the broadband noise is predicted using the regression model. In the scope of this study, the model analysis
of the pressure PSD could not predict the spectral distribution of its broadband noise with the individual function. The prediction of the machine learning could predict not only the broadband noise but its discrete frequency noise to the same levels as the actual measurement. In the prediction
of the machine learning, the regression model trained on a large number of training data could predict the actual noise with the small error.
Simulation and experimental study on impact dynamic characteristics of the spline rotor system
Authors: Song Yuxiang , Ma Xinxing , Zhang Zhenguo
Published: December 2023

The development of accurate impact dynamics models in rotating machinery with spline couplings is a challenging problem that demands special attention. The dynamic behavior of the system is highly dependent on the spline coupling stiffness, which is nonlinear under different loads.
To address this challenge, rotor dynamics models that incorporate spline couplings have been developed. In this paper, firstly, the mechanical model of spline coupling considering large deformation under different loads is established and verified by finite element software. Furthermore, a
spline rotor dynamics model considering nonlinear stiffness is established, and the influence of different impact loads on the vibration response of the system is emphatically analyzed. Finally, the proposed model is experimentally verified to accurately predict the impact dynamics of the
rotor system, which provides a certain theoretical reference for the impact resistance design of the spline rotor system.
Partial sound source estimation with Helmholtz inverse beamforming as a part of pass-by noise virtualization
Authors: Knappe Fabian , Becker Volker , Puhle Christof , Jahnke Alexander , Meyer Andy
Published: December 2023

Noise has an impact on human health. Therefore, pass-by noise of motor vehicles is legally regulated. The latest norm of the Economic Commission for Europe is ECE R51.03. According to this norm, pass-by noise of motor vehicles must be reduced to a sound pressure level of less or equal
68 dB(A). This poses a challenge for original equipment manufacturers. Firstly, they need a detailed analysis on the influence of contributing vehicle components such as engine, exhaust system and tires to the over-all pass-by noise. Secondly, original equipment manufacturers strive to shorten
development cycles and lower production costs. Therefore, predictions of the expected physical behaviour of future cars have gained increasing importance. This leads to the emergence of new technological concepts like digital twins. This paper presents an extension of our latest approach to
partial sound source analysis of simulated pass-by noise, i.e. Helmholtz Inverse Beamforming. Moreover, we present the embedding of the results of Helmholtz Inverse Beamforming in a comprehensive virtualization concept of pass-by noise engineering. By combining Helmholtz Inverse Beamforming
with machine learning predictions of future cars, this concept enables us to derive target values of acoustic components regarding their pass-by noise.
Experimental Study of Aerodynamic Noise Source Measurement around an Automobile Door Mirror by Hot-film Sensor
Authors: Sasaki Soichi
Published: December 2023

In order to the evaluation and identification of the aerodynamic sound source generated from a door mirror of an automobile, the simple measurement technique using the film-type hot film sensor is proposed. In the wind tunnel test of the actual vehicle model, the feasibility on the
qualitative evaluation of the aerodynamic sound sources with the hot film sensor is discussed experimentally. From the results of this experiment, author could explain that the low-frequency broadband noise is one of the features of its aerodynamic noise. The qualitative evaluation of the
hot-film sensor indicated that the low-frequency aerodynamic noise is caused by fluctuations formed at the tips of the door mirrors. Although the location of the low-frequency broadband noise source was identified by evaluating the signal of the hot film sensor, the quantitatively evaluation
of the strength of the aerodynamic sound source could not achieve.
Durability of the noise-reduction performance of the PMSMA and CRSMA pavements - a case study in Hong Kong
Authors: Yang Bin , Leng Zhen , Yuan Minmin , Hung Wing-tat
Published: December 2023

Tyre/road interaction noise is one of the main sources of urban traffic noise, which has aroused public concern about health and living environment. Low-noise road surface (LNRS) is a feasible solution to reduce tyre/road noise from its source. As a high-density city, Hong Kong has
studied the noise-reduction performance of different LNRS materials in the past decade, such as the crumbed rubber modified stone mastic asphalt (CRSMA) and polymer modified stone mastic asphalt (PMSMA) with a small maximum aggregate size. This study aims to evaluate and compare the durabilities
of the noise-reduction performance of CRSMA and PMSMA pavements. The close-proximity (CPX) method was applied to collect the tyre/road noise data over three consecutive years after the pavements were constructed. The sound pressure levels and spectrograms were investigated to compare the noise
reduction durabilities of the two LNRS materials. The results showed that the CRSMA6 pavement showed good and relatively stable noise reduction performance during the whole observation period. In contrast, although PMSMA6 presented a lower noise level than CRSMA6 at the early stage, its noise
reduction property gradually deteriorated. PMSMA6's noise value surpassed CRSMA6 in the third year.
Design of alert sound for electric vehicle based on fluctuation strength for amplitude fluctuation
Authors: Yasui Nozomiko , Miura Masanobu
Published: December 2023

The motor sound of an electric vehicle is quiet at low speeds. Thus, it is difficult for pedestrians to detect vehicles approaching them. This is not only a particular problem for visually impaired people but also for any people who cannot see the approaching vehicle, for example, in
a situation where the vehicle comes from behind or an obstacle object. Therefore, the vehicle was designed to provide an alert sound to solve this problem. The UN Regulation No.138 on Quiet Road Transport Vehicles was adopted and published in 2016. The regulation introduces a minimum sound
level, spectrum, and frequency shift depending on the speed of the vehicle. However, the regulation of the amplitude fluctuation has not been defined. In this study, it is assumed that pedestrians are aware of approaching gasoline vehicles by hearing the amplitude fluctuations in the exhaust
sound. We propose that they can be aware of approaching EV by hearing amplitude fluctuation sounds. Our previous studies found that fluctuation frequency, non-periodic fluctuation, and amplitude envelope influence the sensation of hearing fluctuation or fluctuation strength. Their effects
on pedestrian detectability were assessed in an actual environment. The results indicate that these characteristics are effective in detecting approaching vehicles.
Subjective and objective investigations on environmental properties to be displayed on sensory friendly maps at the Tokyo National Museum
Authors: Kinoshita Arisa , Ueno Kanako , Matsuo Ayako , Suzuki Midori , Masuda Marina
Published: December 2023

Sensory friendly maps are known to be effective in providing advance information to visitors sensitive to environmental stimuli. However, the process of determining the environment al factors to be displayed on sensory friendly maps remains unclear. To provide visitors with useful advance
information, we conducted a subjective evaluation and objective measurements, as a preliminary study, to create a sensory friendly map of the Tokyo National Museum. First, participants with autistic spectrum disorder were asked to explore the entire facility and record their perceptions at
locations that they perceived to be characteristic. Second, objective measurements of the sound and lighting environments were conducted. Subsequently, the relationship between the subjective evaluation and objective measurements was assessed. Consequently, we discovered that some elements
extracted through the subjective evaluation could be explained using objective measures such as the noise level, noise frequency characteristics, and reverberation time. Moreover, we confirmed that, in some cases, the subjective effect of sensory stimulation could change depending on the relationship
with surrounding environments, purpose of the environmental setting, and qualitative factors. In such cases, adequate correspondences between the subjective and objective results could not be established.
Preliminary investigation of the short-term in situ performance of an automatic masker selection system
Authors: Lam Bhan , Ong Zhen-Ting , Ooi Kenneth , Ong Wen-Hui , Wong Trevor , Gan Woon-Seng , Watcharasupat Karn N.
Published: December 2023

Soundscape augmentation or "masking" introduces wanted sounds into the acoustic environment to improve acoustic comfort. Usually, the masker selection and playback strategies are either arbitrary or based on simple rules (e.g. -3 dBA), which may lead to sub-optimal increment
or even reduction in acoustic comfort for dynamic acoustic environments. To reduce ambiguity in the selection of maskers, an automatic masker selection system (AMSS) was recently developed. The AMSS uses a deep-learning model trained on a large-scale dataset of subjective responses to maximize
the derived ISO pleasantness (ISO 12913-2). Hence, this study investigates the short-term in situ performance of the AMSS implemented in a gazebo in an urban park. Firstly, the predicted ISO pleasantness from the AMSS is evaluated in comparison to the in situ subjective evaluation scores.
Secondly, the effect of various masker selection schemes on the perceived affective quality and appropriateness would be evaluated. In total, each participant evaluated 6 conditions: (1) ambient environment with no maskers; (2) AMSS; (3) bird and (4) water masker from prior art; (5) random
selection from same pool of maskers used to train the AMSS; and (6) selection of best-performing maskers based on the analysis of the dataset used to train the AMSS.
Multi-cultural perception of impact sound -- An international online listening survey about the perceived annoyance due to impact sounds
Authors: Cunha Iara Batista da , Skoda Sabrina , Müller-Trapet Markus , Choi Young-Ji , Mahn Jeffrey
Published: December 2023

To support the introduction of requirements for protection from impact noise in the National Building Code of Canada, the National Research Council of Canada implemented pilot subjective evaluations of impact sounds to evaluate the best metric to be used in the Code. As an alternative
to the typical laboratory-based listening experiments, online-based listening tests were used. The ability to collect data with an online survey allows to reach the general public much more than with any laboratory-based experiment, and it was especially relevant in the context of the Covid-19
pandemic, which forced researchers to re-evaluate in-person procedures. This online listening survey was published for world-wide access, enabling data collection across a diverse target audience in many parts of the world. The survey and its preliminary results are presented and discussed
in this paper. Data collected as part of the online survey, such as the person's country of residence and the type of dwelling they lived in, is used to explore the multicultural effects on the annoyance ratings.
Multilingual sound sopt synthesis systems
Authors: Okamoto Takuma
Published: December 2023

Localized sound zone synthesis, which can generate acoustically bright and dark zones using loudspeakers, is gaining attention as one of important acoustic communication techniques. By superposing multiple localized sound zones, multiple sound spot synthesis can simultaneously deriver
different sound signals at different zones using a loudspeaker array. Additionally, it can be implemented as a user interface for real-time speech translation by combining multilingual speech synthesis technology. This paper introduces multilingual sound spot synthesis systems based on spatial
Fourier transform implemented by using compact circular array of 16 loudspeakers and linear array of 64 loudspeakers combined with multilingual neural speech synthesis.
Environmental noise and electrodermal activity: measurements and limits of living lab experiments
Authors: Masullo Massimiliano , Toma Roxana Adina , Ruiz Juan Miguel Navarro , Bellot Jorge Hernandez , Maffei Luigi
Published: December 2023

The scientific literature showed that physiological measurements, especially electrodermal activity, are affected by a series of possible artefacts (movements, respiration), which makes them very challenging. More recently, physiological measures have been increasingly used to investigate
the correlations between the psychophysiological sphere and some environmental characteristics, i.e., EDA response is being used to validate the potential of some places in terms of restoration. However, unlike laboratory experiments, measurements in real-life conditions involve additional
difficulties. This paper discusses the limitations of searching the relationships between electrodermal activity and environmental sound by living lab experiments. The monitoring campaign results at six different spaces at Catholic University of San Antonio campus in Murcia, Spain, are compared.
Results show that EDA measurements are strongly affected by emotion elicited in spaces for the community, while the correlations with sound environment increase in the sites where individual functions are performed.
Promotion of the understanding of sensory diversity through elementary school class activity
Authors: Ueno Kanako , Takahashi Toru , Matsuo Ayako
Published: December 2023

To create a society where all people can participate and support each other, people with various mental and physical characteristics must understand each other. Those with developmental disorders such as autism spectrum disorder often exhibit atypical sensory characteristics such as
hypersensitivity. Therefore, it is important to appropriately recognize individual sensory characteristics and adjust the environment accordingly to prevent overstimulation. To promote understanding of one's own sensory characteristics and sensory diversity and to promote reasonable accommodation,
we implemented a learning program for an elementary school class. First, the children listened to recordings of familiar sounds and indicated their level of concern. These responses were visualized in a "sensory graph" to help the children understand individual differences in sensory
characteristics. Second, they worked collaboratively to identify and map pleasant/unpleasant sounds and lights in the school. Through this activity, they developed an understanding of the different perceptions among their peers. Additionally, we introduced this class activity during teacher
training to promote lessons on sensory diversity.
Auditory-friendly activities for people with autism spectrum disorder
Authors: Takahashi Hidetoshi , Ueno Kanako
Published: December 2023

Autism Spectrum Disorder (ASD) is associated with persistent impairments in adaptive functioning across multiple domains including social, communicative, occupational, and other important areas of daily life. Sensory abnormalities have often been reported as symptoms of ASD, and auditory
over-responsiveness (AOR) is the most common sensory-perceptual abnormality in individuals with ASD. Recently, we reported that a greater magnitude of acoustic startle reflex in response to weak stimuli of 65-85 dB was found in children with ASD compared to those with typical development.
This index was related to various clinical features, including sensory problems, autistic traits, emotional/behavioral difficulties, and adaptive/maladaptive behaviors in ASD children. This intensity level of acoustic stimuli is frequently experienced in everyday situations environment. Noise
affects several aspects of both physical and mental health and those with AOR might be affected more by their daily environment. Thus, for the healthy development of ASD children with AOR it is important to create an auditory-friendly environment. We have conducted several auditory-friendly
activities. These activities might raise awareness about AOR of people with ASD.
Numerical study on the haystack phenomenon of turbulence ingestion noise
Authors: Shao Mingyu , Jiang Hanbo , Huang Xun
Published: December 2023

The haystack phenomenon, i.e., humps and blue shifting in noise spectra, is commonly observed in the study of underwater turbulence-propeller interactions, which is a major contributor to noise radiation. However, its generation mechanism is still unclear, which is vital to develop
noise control strategies. To address this issue, this work conducted numerical simulations concerning the interaction between turbulence and rotors. The propeller is simplified to a cascade model and the turbulence flow is represented by a time series of harmonic gusts for convenience. The
simulations are validated against the Sears model for a gust-airfoil interaction problem. Initial results suggest a convolutional interaction mechanism between the spectra of incoming flow disturbances and the periodic sampling of the cascade, which approves the theoretical analysis from Huang
(AIAA J. 2023). The results is helpful to understanding the physics of turbulence-ingestion rotor noise and designing the next generation underwater vehicles.
Relationship between sound environments and worker's impression evaluation in open-plan offices Part 2: Analysis of sound environment and impression evaluation
Authors: Araki Takumi , Sugahara Akiko , Nagasawa Yasuhiro , Hiraguri Yasuhiro , Togashi Kengo , Harada Kazunori , Iwakiri Yukinobu
Published: December 2023

In recent years, the prevalence of open-plan offices has been on the rise due to their effective enhancement of cognitive productivity through the facilitation of intercommunication among employees. Numerous prior investigations have elucidated the correlation between an acoustic setting
and cognitive productivity by subjecting participants to constrained spaces, such as meeting rooms or laboratories. Nevertheless, limited research has been undertaken to explore the effects of an acoustic setting in office spaces where multiple employees operate. In the context of an open-plan
office, this study seeks to elucidate the connection between an acoustic setting and workers' evaluative perceptions. This manuscript endeavors to present the outcomes of a questionnaire survey administered among office workers. Furthermore, the influence of the acoustic setting on workers'
evaluative perceptions will be examined by leveraging the findings of the acoustic environmentsurvey expounded in Part 1.
Non-destructive evaluation of FSW tool plunge depth in thin metallic sheet weld using low frequency ultrasonic Lamb waves signal
Authors: Mehta Manish Kumar , Gautam Govinda , Joglekar Dhanashri M. , Dwivedi Dheerendra Kr.
Published: December 2023

Thin aluminium alloy sheets find widespread application in industries such as automotive, marine, railway, and aerospace due to their high load capacity-to-weight ratio. Welding has emerged as an effective joining method, surpassing mechanical fasteners and semi-joining processes. However,
fusion welding techniques are susceptible to hot cracking, leading to solidification and liquation cracking. When it comes to lap welded joints in thin metallic sheets, friction stir welding (FSW) has demonstrated exceptional efficiency. To assess weld morphology, non-destructive testing (NDT)
methods are employed, with the ultrasonic method proving capable of measuring weld penetration depth in thick metallic plates using bulk and surface waves. Nonetheless, the role of tool plunge depth (TPD) in FSW, analogous to the weld penetration depth in fusion welding, remains unexplored
through non-destructive means, despite its critical impact on the load carrying capacity of thin structures. Thisstudy aimsto predict the optimal tool plunge depth for achieving high-quality welding in thin structures by utilizing a guided Lamb wave-based non-destructive method. At a low frequency
of 80 kHz, the transmission percentage of the anti-symmetric mode (A0) was calculated for FSW specimens with different tool plunge depths. The findings revealed that the transmission percentage was higher for welds with the optimum tool plunge depth compared to those with low and high tool
plunge depths. This distinctive behavior of the specimens with the optimal TPD towards Lamb wave signals proved useful in predicting the FSW tool plunge depths.