bluuebunny/crossref_metadata_2025 huggingface dataset:
Shaping acoustic radiation induced by vibrotactile rendering on a touch surface
Authors: Park Sangwon , Kim Wheejae , Kim Dongjoon , Park No-Cheol
Published: September 2021

Many electronic devices with touch-sensitive surfaces aim to provide vibrotactile feedback, along with visual or auditory feedback, to facilitate the interaction between the user and the interface. In parallel to these efforts, recent studies developed various vibration rendering techniques,
enabling more complex vibration patterns to be generated on the touch surface. However, few have addressed sound radiation induced by vibrotactile rendering on a touch surface, which could significantly impact the haptic interaction's overall perception. This study presents a method to shape
the acoustic radiation due to rendering high-fidelity vibrotactile feedback on a touch surface. The proposed method utilizes measured frequency response functions and a vibroacoustic representation of the touch surface to define the relationship between actuator driving signals, vibration
responses on the touch surface, and radiated sound power. Proper actuator driving signals are derived from the optimization problem formulated using the relationship. The proposed method was demonstrated through vibration rendering experiments on a touch surface comprising an acrylic plate
and voice coil actuators. The results showed that the proposed method could shape the acoustic radiation while rendering target vibration patterns at desired positions on the touch surface. This study's proposed method could allow haptic engineers to design vibrotactile feedback and sound
radiation simultaneously for a more compelling haptic experience.
Effect of different types of ceilings on floor impact sound insulation performance in CLT model building
Authors: Hiramitsu Atsuo , Hirakawa Susumu , Tsuchimoto Takahiro , Yamauchi Takashi
Published: September 2021

The floor impact noise generated in a building often causes problems among residents. The floor impact sound insulation performance of timber construction buildings is lower than that of concrete construction. However, due to the large supply of wood and the stress-relieving effects
of wood, the use of wood is being promoted around the world. In Japan, the Act on the Promotion of the Utilization of Wood in Public Buildings was enforced to promote the use of CLT (Cross Laminated Timber) for the effective use of wood. We have been experimentally investigating the effect
of floor finish structure in CLT model building. In this paper, we report the measurement results of the change in floor impact sound insulation performance when the suspended ceiling structure was changed. As results, it was confirmed that the effect of the sound-absorbing material in the
ceiling cavity and the effect of the double-layer ceiling board were effective. In addition, it was clarified that the dry-type double floor structure with rubber vibration insulator on its legs is an effective floor finish structure for improvement of heavy and light weight floor impact sound
insulation performances.
Creating a sound-designed sound masking signal for open-plan offices that is both pleasant and has a positive impact on cognitive performance.
Authors: Mueller Benjamin Johannes , Laubengeiger Mariella , Martin Noemi , Leistner Philip
Published: September 2021

In open-plan offices, sound masking is often used to lower speech intelligibility and raise cognitive performance of the employees by reducing the irrelevant speech effect. Classic sound masking methods use speakers built into the ceiling of the office to increase the overall background
noise level in the office and reduce speech intelligibility. However, the emergence of activity based offices is increasing the need for personalized sound masking methods that are no longer used globally in the office, but can be controlled by each employee individually depending on their
activity and, for example, played back through headphones during activities that require particularly intense concentration. The playback of a classical sound-masking noise (e.g. a simple pink noise filtered by -5 dB per octave) via headphones is effective, but not pleasant. For this reason,
a new sound-designed masking signal was developed in the present study, which consists of slowly fluctuating binaural harmonic components, as well as atmospheric sounds like water sounds and masking noise. A listening test with a cognitive task and a survey after each test condition showed
that the developed signal had a similar positive effect on cognitive performance as a classical masking noise, but was rated as significantly more pleasant.
Assessment of delamination location in composite laminates based on a chaotic oscillator method
Authors: Li Xuan , Halim Dunant , Liu Xiaoling
Published: September 2021

The work aims to study the assessment of delamination location in composite laminates using vibration measurement with a chaotic oscillator method. Delamination is a type of damage that commonly occurs in composite laminates, which can cause a severe degradation of their material properties.
The traditional vibration-based methods can encounter difficulties in detecting and locating these delamination-type damages especially when the size of delamination is relatively small and there is a significant level of noise in its vibration measurement. With this particular consideration,
a vibration-based method using a non-linear chaotic oscillator was used in this study due to its sensitivity to the change in vibration signal characteristics. A numerical model of composite laminates with delamination damage under harmonic excitation was developed and the vibration signal
obtained from composite laminates was processed using the chaotic oscillator method. A feature named Lyapunov Exponent (LE) was used as a delamination damage index to describe the characteristics of the chaotic oscillator for cases with delamination at varying structural locations. The effects
of delamination locations on the developed damage index were analyzed in this work. The results showed that there was a strong correlation between the delamination location and the LE feature, even for the case with a relatively high level of measurement noise. The results demonstrated the
effectiveness of the method to identify delamination in composite laminates, which has also the potential to be used to detect other types of damages.
Semi-adaptive active noise cancellation headphones
Authors: Li Song , Schlieper Roman , Peissig Jürgen
Published: September 2021

Active noise cancellation (ANC) headphones are becoming increasingly important as they can effectively attenuate perceived ambient noise. Fixed filters are commonly applied in commercially available ANC headphones due to their robustness. However, they are not capable of adapting to
changes that occur in dynamic environments, resulting in degraded ANC performance. In contrast, adaptive filters are able to update the ANC filters to compensate for noise in dynamic environments, but large estimation errors can occur due to a sudden change in direction/type of noise or secondary
path. Some studies have suggested an ANC system by combining fixed and adaptive filters. Based on this mechanism, we propose a semi-adaptive ANC system in which the fixed and adaptive filters are weighted in real-time. Initially, the weighting for the fixed filter dominates the whole system
to ensure the robustness of the ANC system. Then, the residual error provided by the adaptive filter is simulated and compared to the real measured one to determine the relative weighting between the fixed and adaptive filters. In this study, this approach is applied to a feedback ANC system.
Simulation results show that our proposed approach achieves high noise attenuation performance while maintaining robustness with time-varying secondary paths.
Interlaboratory and proficiency tests for buildings sound insulation field measurements in Brazil - 4th Edition 2020
Authors: da Silva Wunderlich Priscila , Monteiro Carolina , Pierrard Juan de Frias
Published: September 2021

Since 2013 ABNT NBR 15575:2013 entered into force in Brazil, a national technical standard that establishes acoustic requirements for dwellings, that can be verified by means of field measurements procedures performed according to specific ISO standards. Therefore, those requirements
have fostered the acoustic field measurement market, and the number of laboratories has quickly increased across the county. ProAcústica - Brazilian Association for Acoustical Quality, a non-profit entity, aiming to improve the quality of the acoustics business in Brazil has organized
in 2020 the fourth edition of the "Interlaboratory program of field measurements for building acoustics laboratories - INTERLAB Program". This consists of a fundamental tool for acoustic field laboratories to evaluate and verify the quality of their measurement results. This paper
presents the methodologies and procedures used in the interlaboratory program, as well as the results of both the interlaboratory test and the proficiency carried out in São Paulo (Brazil) during 2017 by ProAcústica - Brazilian Association for Acoustical Quality. In this edition
a total number of 25 laboratories have participated (32% more participants than the last edition in 2017) for different type of field tests: airborne sound insulation, airborne facade sound insulation, impact sound level, sound pressure level from service equipment in buildings, and reverberation
time). The main objectives are the evaluation of the precision of the field test methods in the Brazilian market, and the analysis of the performance of the participating laboratories as a quality control tool.
Vibration transmission across fractured beam-to-column junctions of reinforced concrete
Authors: Filippoupolitis Marios , Hopkins Carl
Published: September 2021

To detect human survivors trapped in buildings after earthquakes by using structure-borne sound it is necessary to have knowledge of vibration transmission in collapsed and fragmented reinforced-concrete buildings. In this paper, Statistical Energy Analysis (SEA) is used to model the
vibration transmission in seismic damaged reinforced concrete beam-to-column junctions where the connection between the beam and the column is made only via the steel reinforcement. An ensemble of 30 randomly damaged beam-to-column junctions was generated using a Monte Carlo simulation with
FEM. Experimental SEA (ESEA) is then considered with two or three subsystems to determine the CLFs between the beam and the column with either bending modes or the combination of all mode types. It is shown that bending modes dominate the dynamic response and that the uncertainty of predicting
the CLFs using FEM with ESEA is sufficiently low that it should be feasible to estimate the coupling even when the exact angle between the beam and the column is unknown. In addition, the use of two rather than three subsystems for the junction significantly decreases the number of negative
coupling loss factors with ESEA.
Subtraction Analysis for Predicting the Propagation Effects of Aircraft Noise
Authors: Wang Yiming , Li Kai Ming
Published: September 2021

In 2013, the Federal Aviation Administration and Volpe National Transportation System Center conducted a series of acoustic measurements with a propeller driven aircraft operating in the regions near Houston, Texas. The recorded data on octave band sound levels, aircraft locations,
temperature and wind speed profiles were used in the current study to quantify the uncertainties for predicting the propagation effects of aircraft noise. Use of the Aviation Environmental Design Tool (AEDT) was explored for its accuracy and validity in real world scenarios offered by the
dataset. The sound exposure level (SEL) data for each section of a flight path was used instead of the time history data for reducing the directivity effect of the sound source due to the change in its relative positions with the receivers. A subtraction-based method was introduced to analyze
the propagation effect in which the SELs between two receiver locations were compared. The use of the subtraction method reduces the possible influences of the sound power variations along the flight paths. The measured data for a spiral and a level flight event were presented and the AEDT
predictions on the propagation effects were examined in this paper.
Simulations of poroelastic materials in a complex acoustic system using frequency-dependent parameters in the mid-frequency range
Authors: Kun János , Feszty Daniel , Feszty Dániel
Published: September 2021

Efficiency requirements prompt manufacturers to develop ever lighter acoustic packages in vehicles. Poroelastic materials are essential to achieve the desired interior noise level targets and thus the simulation of their effects is of utmost importance in NVH analyses. However, it is
challenging to achieve good validation between finite element method (FEM) based simulation results and measurements in the mid-frequency range (400-1000 Hz). One possible reason could be the lack of using frequency-dependent Biot-paremeters describing the poroelastic materials (PEM) characteristics
of trims. The present research aims to employ frequency-dependent Biot-parameters for the PEM materials to investigate the acoustic response of a scaled car-like steel structure composed of flat plates and U-section stiffeners enclosing an air cavity. Porous acoustic material is applied to
the walls of the cavity. The focus of the study is to understand the effect of applying frequency-dependent Young's modulus and damping values for the PEM parameters in the 100-1000 Hz range. Simulation results obtained from ESI VPS FEM solver are compared with measurements, with particular
focus on the interior sound pressure levels. The simulation methodology, including discretization techniques, structural damping and fluid damping applications are described in detail.
Using simulation to predict reverberation room performance: Validation and parameter study
Authors: Schmal Jared , Herrin David , Shaw Jennifer , Moritz Charlie , Talbot Alexis , Ghaisas Nikhil
Published: September 2021

Predicting the behavior of a reverberation room is inherently challenging and often puzzling. Many still rely on a time-consuming trial-and-error approach when designing the interior and placing diffusers to achieve a diffuse field. An accurate finite element simulation of a reverberation
room would enable design ideas and modifications to be tested without any downtime of the physical room. Room modifications of interest are diffuser geometry, material, size, and placement, and the addition of tuned absorbers. For a simulation to be capable of such a task, each surface would
need to accurately emulate the material specific behaviors occurring in the room. A finite element simulation in Actran VI was tuned to reflect the real-world low-frequency behavior of the reverberation room at Blachford Acoustics located in West Chicago, IL. A detailed analysis of the process
and methods used to create and verify the model are discussed. This is followed by a simple parameter study to look at some modifications of interest.
Simulation of the frequency split of the fundamental air cavity mode of a loaded and rolling tire by using steady-state transport analysis
Authors: Choi Won Hong , Bolton J. Stuart
Published: September 2021

It has been found that when a tire deforms due to loading, the fundamental air cavity mode splits into two due to the break in geometrical symmetry. The result is the creation of fore-aft and vertical acoustic modes near 200 Hz for typical passenger car tires. When those modes couple
with structural, circumferential modes having similar natural frequencies, the oscillatory force transmitted to the suspension can be expected to increase, hence causing increased interior noise levels. Further, when the tire rotates, the frequency split is enlarged owing to the Doppler effect
resulting from the airflow within the tire cavity. The current research is focused on determining the influence of rotation speed on the frequency split by using FE simulation. In particular, the analysis was performed by using steady-state transport analysis which enables vibroacoustic analysis
in a moving frame attached to tire in the frequency domain. The details of the modeling are described and results are given for a tire under different rotation speeds, presented in terms of dispersion curves that illustrate the interaction between structural and acoustical modes. The results
are compared to those for static tires and tires spinning without translational velocity to highlight the effects of rolling.
Physiological and psychological responses to soundscapes and their connections using machine learning
Authors: Yang Ming , Laufs Christian
Published: September 2021

Acoustic environment has significant impacts on humans' feelings and emotions, cognitive performance, and behaviours. It evokes both physiological and psychological responses, which in the long term affect physical and mental health. It has been long believed that physiological and
psychological responses are interconnected, yet their correlations are complex and may vary among conditions and studies. This present research study explores the physiological and psychological responses at the exposure to acoustic environment in a short period of time, and examines whether
the physiological responses are able to predict the psychological responses. In this research, the physiological and psychological responses of subjects to a set of soundscapes are collected in a laboratory setting, by respectively continuous physiological measurements and self-report ratings
on subjective experiences. The connections between the physiological and psychological responses are examined using machine learning methods. The results show the connections between physiological and psychological responses to soundscape. To a certain degree, it is able to predict the psychological
responses from the measured physiological responses.
Air-cooled chiller screening noise analysis with preliminary building project information
Authors: Storm Mark
Published: September 2021

For Inter-noise 2018, the author submitted a paper proposing techniques to derive reasonable preliminary estimates of building project stationary noise emission levels from sparse but available data that may seem unrelated to noise or vibration such as gross square footage (GSF), expected
occupancy, and land use or function. Results from these predictions would be used to support or refine established buffer distances between exposed outdoor heating, ventilating, and air-conditioning (HVAC) system noise sources and nearby noise-sensitive receptors, helping planners tasked with
ambitious infill or growth goals better fit building projects into complicated campus development puzzles. This paper provides supplemental guidance by linking the same preliminary building project GSF, occupancy, and function information to estimates of cooling load (expressed as refrigeration
tonnage) and thus an additional HVAC consideration not discussed in the author's previous study. When such refrigeration relies upon air-cooled condensers installed outdoors on building rooftops or at grade, substantial noise sources are introduced to the environment. Thus, this new study
shares data and methodology to help expand the value and utility of the previous work and potentially provide more comprehensive building HVAC noise estimates for use by building developers and planners.
Proacustica Handbook: noise and vibration control in building installations
Authors: Nepomuceno Jose , Wunderlich Priscila
Published: September 2021

Proacústica is a nonprofit entity created in 2010 to congregate companies and professionals willing to leverage the development of acoustics in Brazil. Three technical committees (TCs): Environmental Acoustics, Building Acoustics, and Room Acoustics, contribute to the drafting
of laws, standards, production of technical content, and integration between different players of the market. By 2021, the Room Acoustics TC incorporated three Working Groups: Special Rooms, Schools and Noise Control and Vibration Control - the last one dedicated to the Proacustica Handbook:
Noise and Vibration Control In Building Installations. The purpose of this publication is to describe the step-by-step measures to implement noise and vibration control strategies in buildings. These strategies are aimed at the particularities of the Brazilian market at the moment and also
a way to improve how M/E/P equipment manufacturers, installers, designers, and acoustic consultants approach the subject from the design to the construction, Important technical discussions among participants included: the use of sound pressure versus sound power data for equipment; the sound
rating for diffusers, VAVs, and other ductwork devices; vibration isolation guidelines, among other topics. This paper presents the Handbook structure, relevant discussions, and recommendations to be published as a final document by the end of 2021.
Head tracker using webcam for auralization
Authors: D'Andrea Fonseca William , Rocha Carvalho Davi , Hollebon Jacob , Mareze Paulo Henrique , Fazi Filippo Maria
Published: September 2021

Binaural rendering is a technique that seeks to generate virtual auditory environments that replicate the natural listening experience, including the three-dimensional perception of spatialized sound sources. As such, real-time knowledge of the listener's position, or more specifically,
their head and ear orientations allow the transfer of movement from the real world to virtual spaces, which consequently enables a richer immersion and interaction with the virtual scene. This study presents the use of a simple laptop integrated camera (webcam) as a head tracker sensor, disregarding
the necessity to mount any hardware to the listener's head. The software was built on top of a state-of-the-art face landmark detection model, from Google's MediaPipe library for Python. Manipulations to the coordinate system are performed, in order to translate the origin from the camera
to the center of the subject's head and adequately extract rotation matrices and Euler angles. Low-latency communication is enabled via User Datagram Protocol (UDP), allowing the head tracker to run in parallel and asynchronous with the main application. Empirical experiments have demonstrated
reasonable accuracy and quick response, indicating suitability to real-time applications that do not necessarily require methodical precision.
Subjective studies on impact sound in times of a pandemic -- a comparison between a laboratory study and an online listening test
Authors: Mueller-Trapet Markus , Batista da Cunha Iara , Mahn Jeffrey
Published: September 2021

The National Research Council Canada is currently investigating the perceived annoyance due to impact sound in multi-unit residential buildings (MURBs). The first part of a subjective laboratory study on a number of different floor/ceiling assemblies was completed with 26 participants
just before the start of the Covid-19 pandemic in 2020. To evaluate the feasibility of carrying out a similar study without in-person attendance, the same stimuli from the laboratory study were used to create an online listening test. The online listening test was created in JavaScript and
HTML5 to run on any internet browser. This paper will present the results of the online listening test and compare them to the laboratory study, focusing on the obvious drawbacks of an uncontrolled remote study such as the uncertainty due to the participants' headphones and listening environment.
With an expectation that in-person studies will remain difficult to realize in the near future, this contribution provides evidence whether remote subjective listening tests are a viable alternative to controlled laboratory studies for impact sound.
Enhancement of sound absorption in a band frequency using thin porous layer-lined metasurfaces
Authors: Lee Joong Seok , Park Jun Hyeong , Ma Pyung Sik , Kim Shin Young , Kim Yoon Young
Published: September 2021

When a porous layer is installed on a hard wall, sound absorption performance is mainly determined by thickness of the layer. Although material parameters of porous materials are strongly dependent on frequencies, the thickness limitation related to the quarter wavelength of incident
sound wave has been a key factor in the treatment of porous layers for noise reduction. This implies that a thicker porous layer is required to absorb lower-frequency sound effectively. To overcome the thickness limitation, metaporous layers, which are named as a compound of sound absorbing
porous layers with the concept of metamaterials have received much attentions for alternative implementations of porous layers. Recently, we proposed a new type of metaporous layer for enhancing sound absorption performance in a specified broad frequency band. The proposed metaporous layer
is constructed with a thin porous layer backed by a reactive metasurface consisting of an array of bent channels. Formation of sound absorption band is directly determined by the characteristics of scattered sound field from the proposed metaporous layer. Analytical and numerical investigations
show that the metasurface is considerably responsible for the enhanced sound absorption in the proposed metaporous layer, while sound dissipation occurs only in the thin porous layer.
Artificial Neural Network Model for Road Pavement Classification using Features of Tire-Pavement Noise and Road Surface Images
Authors: Chang Seo Il , Kim Bo Kyeong , Lee Jae Kwan
Published: September 2021

Artificial neural network models were developed to classify road pavement types into the transverse-tined, the longitudinal-tined, NGCS(Next Generation Concrete Surface), Diamond Grinding, and Stone Mastic Asphalt by utilizing tire-pavement noise and road surface images. Tire-pavement
noise data were collected by OBSI(On-Board Sound Intensity) method, and analyzed to obtain sound intensity level, sound pressure level, and sound quality indices. Road surface image data was analyzed through image feature extraction algorithms of Hough transformation and HOG(Histogram of gradient).
The important features among the acoustic and image characteristics were selected by a random forest model. The acoustic features selected by the random forest algorithm are the overall sound intensity level of 400~5kHz 1/3-octave bands, the sound intensities (W/m2) of 800~2kHz 1/3-octave
bands, loudness, fluctuation strength and tonality. The image features selected are the number of longitudinal lines extracted from Hough transform algorithm and HOG of the central cell. The two groups of the selected features were applied separately or together to an artificial neural network
model to find classification performance. The classification accuracy rates of the models using acoustic features only, image features only and both acoustic and image features combined were 90.8%, 88.8%, and 97.3%, respectively.
Acoustical performance of horizontal-sliding-panel operable partition walls
Authors: Borzym Jim
Published: September 2021

Field measurements of airborne sound transmission loss were made on several operable partitions of the horizontal-sliding-panel type between conference rooms. Apparent Sound Transmission Class (ASTC) and Noise Isolation Class (NIC) ratings were computed. Very significant deviation of
field-measured sound transmission ratings and manufacturers' Sound Transmission Class (STC) ratings were found. Clients were not satisfied by actual sound isolating performance. Transmission of voice was clearly audible. Some deficiencies of field conditions were found. Some deficiencies of
partition installation were found. Modifications were made; acoustical performance did not change significantly.
Effect of visual elements on Indoor soundscape perception in open-plan office
Authors: Santika Beta Bayu , Joo Hyun In , Jeon Jin Yong
Published: September 2021

This study examined the effect of changes in visual elements on spatial comfort and work productivity in the aspect of indoor soundscape perception in the open-plan office (OPO) sound environment. Various OPO visual stimuli were simulated using computer software (Unity 3D engine) to
change the visual environment by varying variables such as worker density, window ratio, green ratio, and ceiling height. An interactive virtual reality environment was implemented to perform a specific task while experiencing the audio-visual stimuli combining the general OPO noise stimulus
and the simulated OPO visual stimulus. Subjective evaluation was performed on a total of 30 subjects to evaluate indoor soundscape quality and work performance for each stimulus. Based on the results of this study, a pleasant OPO design guideline was proposed. Keywords: Open-plan office, indoor
soundscape, interactive VR test, spatial comfort
Just noticeable difference of sound pressure level of speech in open-plan office
Authors: Lee Haram , Santika Beta Bayu , Jo Hyunin , Jeon Jinyong
Published: September 2021

In this study, the general sound environment characteristics of open-plan office (OPO) were investigated, and just noticeable difference (JND) of sound pressure level of speech at a distance of 4 m (Lp,A,S,4m) suggested in ISO 3382-3 was suggested. First, in order to understand the sound environment characteristics of OPO, one minute sound sources recorded in 8 offices were collected and physical and psychological acoustic characteristics were analyzed. A total of 30 office workers were subject to subjective evaluation on 8 sound sources, and they were asked to respond to questionnaires related to annoyance, work satisfaction, and speech privacy. Next, to investigate the JND, two computer simulation models identical to those of the actual OPO were implemented, and sound sources each having six different Lp,A,S,4m values were generated through the change of the sound absorption coefficient of the interior finish. The JND of Lp,A,S,4m was presented by performing paired comparison for the same subjects. It is expected that the JND of Lp,A,S,4m proposed in this study can be used for the sound environment rating of OPO.
A comparison of standardized methods for sound attenuation test of hearing protectors
Authors: Yokoyama Sakae
Published: September 2021

In order to prevent hearing impairment due to occupational noise, it is essential to wear hearing protectors such as earplugs and earmuffs, especially in an extremely noisy environment. The method of measuring their sound attenuation is defined by international standards such as ISO
and IEC, and standards such as ANSI, BS, AS/NZS, JIS et.. Although most standards recommend subjective methods where the thresholds of hearing shall be measured once with open ears and once with the hearing protector in place for each subject, measurement and evaluation methods are not unified
internationally. In Japan, in April 2020, the old product standard was abolished in consideration of international consistency, and a new method standard was established with the ISO standard as the corresponding international standard for the first time in about 40 years. In this study, we
compared the measurement methods and evaluation methods according to the standards for sound attenuation tests of hearing protectors.
Apparent impact sound insulation performance of cross laminated timber floors with floating concrete toppings
Authors: Zhou Jianhui , Zhao Zijian
Published: September 2021

Mass timber buildings are gaining increasing popularity as a sustainable alternative to concrete and steel structures. Mass timber panels, especially cross-laminated timber (CLT), are often used as floors due to their dry and fast construction. CLT has poor impact sound insulation performance
due to its lightweight and relatively high bending stiffness. Floating concrete toppings are often applied to increase both the airborne and impact sound insulation performance. However, the impact sound insulation performance of floating concrete toppings on CLT structural floors is affected
by both the concrete thickness and resilient interlayer. This study investigated the efficiency of both continuous and discrete floating floor assemblies through mock-up building tests using small-scale concrete toppings according to ASTM E1007-16. It was found that the improvements by continuous
floating floor assemblies are dependent on the concrete thicknesses and dynamic stiffness of resilient interlayers. The improvements cannot be well predicted by the equations developed for concrete structural floors. The highest apparent impact sound insulation class (AIIC) achieved with continuous
floating floor assemblies in this study was 53 dBA, while that of the discrete floating floor assemblies was up to 62 dBA. The discrete floating floor solution showed great potential for use in mass timber buildings due to the high performance with thinner concrete toppings.
Accurate and controled vehicle pass-by noise emission quantification in real life traffic
Authors: Pinel Lamotte Lucille , Lepercque Fabien , Baron Valentin
Published: September 2021

Noise emission from individual vehicle largely contributes to city pollution and has serious health impact. The standards towards vehicle manufactures consists in pass-by testing with specific acceleration conditions which are not representative of all real driving. For the 2015/996
EU directive, the vehicle source model is inspired of the preceding pass-by standard with derived data represented the propulsion and rolling noise sources. Anyhow, those sources are underestimated due to driving behavior, aged and modified vehicle, road surface, meteorological conditions...
The true data collection of vehicle pass-by would be interesting. Moreover, some of the countries are reflecting on how to fight against those extremely noisy vehicle exceeding noise limit with efficient monitoring systems. This paper presents an innovative tool able to detect, identify and
quantify the noise emission of individual pass-by vehicle in real life traffic. It is based on the combination of array and video processing. Compared to the state of the art and thanks to MEMs technology, the system is optimized and designed to quantify the individual noise vehicle emission
regarding standard with controlled measurement and accurate processing. If the conditions are not respected to properly qualify the pass-by regarding the system limits, the data are ignored. It aims at constructing large and accurate database useful to determine average noise levels and/or
acceptable noise limits per vehicle category.
Towards fully controlled anisotropy in cellular porous media: an overview
Authors: Gaborit Mathieu , Mao Huina , Rumpler Romain , Göransson Peter
Published: September 2021

In the recent years, our team has been working to identify key aspects of anisotropy on porous media. More than just characterising their anisotropic properties, we're interested in generating cellular media with completely designed anisotropic properties. The results of these studies
have partly been published and more are to come. In this presentation, we'll present an overview of this work and it ultimately ties to acoustics. We will introduce the key findings,discussed specific results that can be achieved and provide context and details related to the strategy developed
to address the tasks.
Reducing Employee Noise Exposure in Manufacturing: A Review of the 2014 workshop
Authors: Murphy William
Published: September 2021

In 2014, the Institute for Noise Control Engineering (INCE) Foundation, the Noise Control Foundation and the National Institute for Occupational Safety and Health organized a meeting of industry, government, and academic experts to discuss "Reducing Noise Exposures in the Manufacturing:
Best Practices, Innovative Techniques, and the Workplace of the Future." This presentation will review the content of the recommendations for hearing loss prevention programs, successful implementations for noise control engineering, and new techniques to predict noise exposures in the
workplace. Efforts to develop Buy Quiet programs and to promote the Safe-in-Sound Excellence in Hearing Loss Prevention and Innovation will be reviewed.
Numerical modeling of ground-borne vibrations induced by pile driving with a simple and direct material damping approach
Authors: Sofiste Tales , Godinho Luís , Soares Delfim , Alves Costa Pedro
Published: September 2021

Ground-borne vibrations are an increasingly common problem in large cities due to its considerable disturbance in terms of human comfort and health. In this sense, construction operations stand as a significant source of vibrations and may be critical since construction sites are frequently
adjacent to existing buildings. In the present work, vibrations induced by pile driving are studied. A time-domain finite element model is developed and a post-processing approach is proposed to simulate the material damping of the soil. This damping formulation stands as a simple and direct
approximation of the material damping in the system. In order to do so, the numerical response is computed without material damping, which is introduced as a post-processing procedure. An explicit and highly efficient method is applied for the time integration of the equation of motion, considering
an axisymmetric formulation. A numerical application is carried out and the obtained results are compared to previous numerical and in-situ measurements available in the literature, indicating a good agreement with previous studies.
Noise reduction of enhanced acoustic balconies on a high-rise building block
Authors: Tang SK , Lee Rudolf YC
Published: September 2021

A new device called 'enhanced acoustic balcony' is installed in a new housing estate in Hong Kong. It is intended to help reduce the impact of traffic noise on the residents. This balcony is basically an enlarged form of a plenum window and with three openings. Apart from the outdoor
air inlet, there is the balcony door and a side-hung window on the interior balcony wall for natural ventilation of the indoor space. Sound absorption of NRC 0.7 is installed on the balcony ceiling and its sidewall facing the incoming traffic noise and an inclined panel is installed outside
the balcony to provide noise screening. A site measurement of its noise reduction is carried out in the present study in a newly completed housing block. A 28 m long loudspeaker array is used as the sound source. The indoor noise levels are measured according to ISO standard. The results show
that the difference between indoor and outdoor noise levels in the presence of this balcony form varies over a relatively narrow range between 10 to 13 dBA for an elevation angle from 25 to 60 deg. There is a weak increase of the noise level difference with elevation angle.
Deconvoluting acoustic beamforming maps with a deep neural network
Authors: Gonçalves Pinto Wagner , Bauerheim Michaël , Parisot-Dupuis Hélène
Published: September 2021

Localization and quantification of noise sources is an important scientific and industrial problem, the use of phased arrays of microphones being the standard techniques in many applications. Non-physical artifacts appears on the output due to the nature of the method, thus, a supplementary
step known as deconvolution is often performed. The use of data-driven machine learning can be a candidate to solve such problem. Neural networks can be extremely advantageous since no hypothesis concerning the environment or the characteristics of the sources are necessary, different from
classical deconvolution techniques. Information on the acoustic propagation is implicitly extracted from pairs of source-output maps. On this work, a convolutional neural network is trained to deconvolute the beamforming map obtained from synthetic data simulating the response of an array
of microphones. Quality of the estimation and the computational cost are compared to those of classical deconvolution methods (DAMAS, CLEAN-SC). Constraints associated with the size of the dataset used for training the neural network are also investigated and presented.
Nonlocal acoustic metasurface absorber for ultra-broadband sound absorption
Authors: Zhu Yifan , Assouar Badreddine
Published: September 2021

Classical designs of acoustic meta-absorber usually have a trade-off between bandwidth, efficiency and thickness. Here, we introduce the concept of nonlocal acoustic metasurface absorber by using a bridge structure connecting resonating unit cells to improve the performances of the
meta-absorber. By utilizing the coupling effect between the adjacent unit cells, ultra-broadband sound absorption is achieved with deep-wavelength thickness. The physical mechanism of the nonlocal acoustic metasurface absorber is investigated by developing analytical models. We theoretically
and numerically study the nonlocal metasurface with connecting bridge and the traditional metasurface without bridge. The nonlocality can introduce three specific effects: 1. Optimizing of effective acoustic impedances. 2. Shift of Fabry-Perot resonant frequencies. 3. Strengthening of the
coupling effects between adjacent unit cells. These effects help to improve the bandwidth and the efficiency of the acoustic meta-absorber. We numerically and experimentally achieve an averaged absorption coefficient larger than 0.9 within the ultra-broadband bandwidth from about 600 Hz to
2600 Hz, with a sample thickness of 6.8 cm, , /9 for the lowest frequency. Our finding demonstrates the advantage of non-local acoustic metasurface to conceive subwavelength sound meta-absorber.
Noise impact assessment of onshore and offshore wind turbine
Authors: Sun Hyosung
Published: September 2021

Because of climate change and environmentally friendly energy policy in Korea, the demand for a new renewable energy development has been increased. Especially, the onshore and offshore wind turbines have played an important role in the power system for generating eco friendly energy.
However, in the stage of constructing and operating the onshore and offshore wind turbines, the aerodynamic and underwater noise effect on human and marine life becomes a prominent figure on a social issue, and it is necessary to prepare the assessment method of these noise impacts in order
to prevent the influences on human and marine life in advance. Therefore, this paper is focused on suggesting the evaluation plans of the noise effect from the onshore and offshore wind turbines.
Wave-based control for nonreciprocal acoustics using a planar array of secondary sources
Authors: Tan Joe
Published: September 2021

There has been significant interest in the design of nonreciprocal acoustic devices that allow acoustic waves to be perfectly transmitted in one direction, whilst the acoustic waves propagating in the opposite direction are blocked or reflected. Previously proposed nonreciprocal acoustic
devices have broken the symmetry of transmission by introducing nonlinearities or resonant cavities. However, these nonreciprocal acoustic devices typically have limitations, such as signal distortions and the bandwidth over which nonreciprocal behaviour can be achieved is narrow. This paper
will investigate how active control can be used to minimise the transmitted and reflected waves independently to achieve nonreciprocal sound transmission and absorption using a planar array of secondary sources in a two-dimensional environment. The advantage of the proposed active control
system is that it is fully adaptable, which means that the directivity of nonreciprocal behaviour can also be reversed. The performance of the proposed wave-based active control system is investigated for a range of angles of incidence and its performance limitations are explored.
Noise Reduction by Rail Damper Tunable for Individual Rails in Curve
Authors: Ho Wilson , Soltanieh Ghazaleh , Wang Wylong
Published: September 2021

Tuned mass rail dampers are cost effective for the mitigation of the airborne noise and vibration with the ability to be tuned for individual site. TMDs have been developed and installed at a single rail in a curve tunnel and achieve more than 4dB(A) noise reduction in many cases. According
to the on-site noise reduction performance during damper installation, half, one, two or three dampers can be installed at each spacing between two baseplates. TMDs with only half-installation provides more than 10dB reduction at vertical pin-pin resonance (~1kHz). With the standard installation,
they provide the strong damping to half the corrugation growth rate. The stick-slip phenomena which causes the corrugation will be affected by the damping effect from TMDs. On the other hand, they can also be tuned to the low-frequency (p2 resonance) for grandborne noise control. The high
reduction of the grand borne noise proved our claim for effectiveness of the TMDs besides many other studies on the other parameters like the type of the baseplates or the soil types. According to the test results TMDs achieve strong performance in different range of the frequencies.
Managing Construction Noise in Hong Kong - Facing a New Decade with Confidence
Authors: Ho Wilson , Lam Kin-Che , CHENG Morgan , Yiu Max , Lo Hannah Chin-wing , Lai Jamie Chi-ting , Wong Cheung-lam
Published: September 2021

Hong Kong is a mature and busy metropolis with 7.5 million residents. Being constrained by limited land area for development, the cityscape of Hong Kong is primarily 3-dimensional in nature. The vast majority of the growing population is accommodated in closely packed high-rise residential
towers. Similar to other major urban centres worldwide, Hong Kong citizens are affected by the virtually continuous construction activities expanding and renewing the city. The numerous construction sites are also bringing noise disturbance to some neighbourhoods. In 2020, the Hong Kong Environmental
Protection Department completed a feasibility study on managing construction noise, including those associated with renovation of domestic premises. Part of the study was the conducting of face-to-face interviews of more than 5,000 households via a large scale public survey to gauge their
views on construction noise disturbance, among others. This paper describes the current state and conditions of construction noise in Hong Kong, the issues and constraints, as well as challenges and opportunities. Highlights from the scientifically conducted public survey will be included
to provide a robust and more comprehensive description of the prevailing situation.
Impact sound transmission: experiments of control at the receiver room
Authors: Akkerman Davi , Weitbrecht Paola , Shieko Mariana , Borin Marcel , Jacomussi Leonardo
Published: September 2021

Considering Impact sound level requirements accomplishment in Brazil, floating floors are still considered as an inviable solution for building companies due to the implications in the total cost of building, mainly for social housing. Alternative and sometimes cheaper solutions are
those undertaken in the receiver room. However, the lack of laboratory and field tests on the acoustic performance of this type of system is still a barrier for acoustic designing in Brazil. The aim of this paper is to study and validate different constructive solutions developed jointly with
building companies for improving the impact sound insulation performance on the receiving room of new Brazilian housing constructions.
Industrial fan vibration signature characterization
Authors: Copeland Timothy , Kohn Arthur , Southall Orrin
Published: September 2021

Technique for measuring and reducing industrial fan vibration and noise is detailed. A method used to characterize the vibration signature for 100% industrial fan systems shipped is described. A fan system consists of motor, propeller and cage. We measure triax accelerometer vibration,
microphone (both sound pressure level in dBA and raw signal in Pa) along with the current of three phase power for each fan shipped. Comparisons are done immediately with the ISO 14694:2003 standard and troubleshooting and design changes are implemented if vibration limits are exceeded. The
method and results are provided for several cases. Troubleshooting and best practices are described for various designs. A portable system takes measurements in the field which are compared to the factory baseline characterization in real time to solve installation problems.