<body>
<center>
<h1>AAS2024: Acoustics 2024: Acoustics in the Sun<br>
Venue, Location, Date</h1>
</center>
<p style="font-weight: bold; text-align: center;"><font size="+2">Table of Contents</font></p>
<ul id="Toc">
<ul>
<li>Session 1A: Vibration</li>
<ul>
<li><a href="#p19">Advanced Analysis of Ground-Borne Vibration Noise Impacts for Underground Railway Tunnel Construction</a></li>
<li><a href="#p87">A New Analysis of the Normal Modes of a Large English Church Bell</a></li>
</ul>
<li>Session 1C: Architectural and Building Acoustics</li>
<ul>
<li><a href="#p96">Analysis of passive methods to provide noise attenuation for apartments with natural ventilation. Case Studies - Part 1</a></li>
<li><a href="#p123">Analysis of passive methods to provide noise attenuation for apartments with natural ventilation. Case Studies - Part 2</a></li>
</ul>
<li>Session 1D: Windfarms</li>
<ul>
<li><a href="#p114">An Approach to Compare Amplitude Modulation Depth and Penalty Schemes for Wind Farms</a></li>
<li><a href="#p7">Evaluating Noise Criteria for Wind Farms: A Comparison of Background Noise Curve Fitting and Wind Speed Bin Data Post-Processing</a></li>
</ul>
<li>Session 1E: Risk & Acoustics</li>
<ul>
<li><a href="#p60">Managing Construction Noise and Vibration Impacts by Risk Optimisation</a></li>
<li><a href="#p10">Using a Monte Carlo simulation to account for source uncertainty in construction noise predictions</a></li>
</ul>
<li>Session 2A: Railway Noise and Vibration</li>
<ul>
<li><a href="#p51">A screening method to predict indicative groundborne noise and vibration from light rail and heavy passenger rail and assess impacts for human comfort</a></li>
<li><a href="#p20">Validated airborne noise models of Perth metropolitan trains</a></li>
<li><a href="#p34">Railway Ground-Borne Noise in Terrace Houses: A Case Study</a></li>
<li><a href="#p83">Investigation into noise attenuation strategies within train tunnels</a></li>
</ul>
<li>Session 2B: AI and Acoustics</li>
<ul>
<li><a href="#p31">AI in Architectural Acoustics</a></li>
<li><a href="#p119">An economic workflow for training machine learning models to classify acoustic data</a></li>
<li><a href="#p70">Advancing AI-based Acoustic Classifiers for (Rail) Construction Noise</a></li>
<li><a href="#p11">An audio dataset and hierarchical taxonomy for disaster scenes</a></li>
</ul>
<li>Session 2C: Architectural and Building Acoustics</li>
<ul>
<li><a href="#p86">Towards a Better Integration of Room Acoustic and Sound System Design for Multipurpose Venues</a></li>
<li><a href="#p120">A Case for Review of PartF7 of NCC BCA</a></li>
<li><a href="#p2">Choral singers' perception of on-stage reverberance during an Australian tour</a></li>
</ul>
<li>Session 2D: Underwater Acoustics</li>
<ul>
<li><a href="#p52">The first study of ambient noise in Australia waters and how it influenced future work</a></li>
<li><a href="#p44">Exercises in Validating Shallow Water Pile Driving</a></li>
<li><a href="#p8">Weston α Description of Seafloor with Fast Fluid Layer over Basement Half-space</a></li>
<li><a href="#p32">Underwater noise studies to support environmental impact assessment in Cockburn Sound, Western Australia</a></li>
</ul>
<li>Session 3A: Transport Noise</li>
<ul>
<li><a href="#p64">RONDA CPX Trailer Measurements of Heavily Degraded Open Graded Asphalt</a></li>
<li><a href="#p26">How Have NR Locomotive Noise Levels Changed Over Time?</a></li>
</ul>
<li>Session 3B: Environmental Acoustics</li>
<ul>
<li><a href="#p78">Open-cycle gas turbines: Predicting and controlling far-field noise</a></li>
<li><a href="#p68">Mitigation of Residential Air-Conditioning Condenser Noise</a></li>
</ul>
<li>Session 3C: Architectural and Building Acoustics</li>
<ul>
<li><a href="#p36">Vibration and Airborne Sound in Repurposed Buildings: A Case Study of a Drum Kit in a Music Classroom</a></li>
<li><a href="#p61">Designing and Complying with the Acoustic Objectives for Metro Railway Stations.</a></li>
<li><a href="#p30">Considerations of External Noise and Vibration Factors in the Design of Sensitive Inpatient Facilities</a></li>
</ul>
<li>Session 3D: Underwater Acoustics</li>
<ul>
<li><a href="#p99">Developing geoacoustic seabed models for a shallow embayment with an elastic seafloor</a></li>
<li><a href="#p53">Bellhop Underwater Acoustic Simulation and Data Processing Optimisations: Getting Hi Def on the Desktop</a></li>
<li><a href="#p75">Measuring the frequency characteristic of underwater sound recorders ST500 and ST600 from Ocean Instruments</a></li>
<li><a href="#p89">Vibroacoustic response of a coated shell near a free sea surface</a></li>
<li><a href="#p91">Transition from perturbation to Kirchhoff approximation for modelling coherent reflection of underwater sound from rough sea surfaces</a></li>
</ul>
<li>Session 3E: Vibration</li>
<ul>
<li><a href="#p97">Novel prototype testing methods for vibration sensitive locations</a></li>
<li><a href="#p118">Experimental vibration analysis of a beam with ABH stiffeners</a></li>
<li><a href="#p65">Coupling of Circumferential Modes in a Circular Plate</a></li>
</ul>
<li>Session 4A: Vibration</li>
<ul>
<li><a href="#p14">Footfall vibration on a high frequency walkway.</a></li>
<li><a href="#p42">Vibration Criterion Curves - Part 2: Application to Transients</a></li>
<li><a href="#p41">Vibration Criterion Curves - Part 1: Evolution and Interpretation</a></li>
<li><a href="#p6">Human-Induced Vibrations on Lightweight Footbridges</a></li>
</ul>
<li>Session 4B: Policy and Acoustics</li>
<ul>
<li><a href="#p28">The Victorian Environment Reference Standard and how it has been considered and applied in noise assessments</a></li>
<li><a href="#p103">Fairly assigning noise emission limits to new industrial precincts.</a></li>
<li><a href="#p15">A framework for drone noise management in an Australian context</a></li>
<li><a href="#p104">Noise assessment methodology for land-use planning</a></li>
</ul>
<li>Session 4C: Architectural and Building Acoustics</li>
<ul>
<li><a href="#p88">Lessons in Education Building Design</a></li>
<li><a href="#p67">A Parametric Study of Sound Leakage Through Openings and Fittings</a></li>
<li><a href="#p112">Design and Verification of a High-Performance Acoustic Testing Laboratory</a></li>
<li><a href="#p49">A Comparative Assessment of Educational Acoustic Design Guidelines against NSW EFSG</a></li>
</ul>
<li>Session 4D: Instrumentation and Measurement</li>
<ul>
<li><a href="#p115">A practical modification to ISO 8297:1994 for unattended sound power level measurement of land drilling rigs.</a></li>
<li><a href="#p72">Detection of aircraft noise with a buried fibre-optic array</a></li>
<li><a href="#p66">Variation in acoustic radiation of a fluid-loaded cantilever excited by point or distributed force</a></li>
<li><a href="#p54">Denoising by neural network for muzzle blast detection</a></li>
</ul>
<li>Session 5A: Psychological and Physiological Acoustics</li>
<ul>
<li><a href="#p100">Evidence-Based Interventions for Auditory Processing Issues in Individuals Who are Neurodiverse</a></li>
<li><a href="#p76">The effect of white noise and "coloured" noise on cognition and sleep</a></li>
</ul>
<li>Session 5E: Policy and Amenity</li>
<ul>
<li><a href="#p37">Preventing sleep disturbance using a qualitative approach</a></li>
<li><a href="#p45">Considerations and strategies for cumulative industrial noise management using the NSW Noise Policy for Industry (NPfI)</a></li>
<li><a href="#p74">Assessing Noise Amenity Within the Context of an Occupational Noise Assessment</a></li>
</ul>
<li>Session 6A: Environmental Acoustics</li>
<ul>
<li><a href="#p35">The Sonic Gathering Place Installation, Melbourne: User Experience and Post-Hoc Assessment of Sound Levels</a></li>
<li><a href="#p117">Modeling Low-Frequency Sound Propagation in a Ducted Atmosphere Using a Semi-Analytic Finite Element Method</a></li>
<li><a href="#p29">Report review for consulting acousticians</a></li>
<li><a href="#p113">Temperature Inversion Frequency From Sigma-Theta</a></li>
</ul>
<li>Session 6C: Noise and Vibration Control</li>
<ul>
<li><a href="#p16">Noise Management Strategies: Large-Scale Solar BESS Projects in Australia</a></li>
<li><a href="#p98">Design and implementation of a masking system for tonal industrial noise emissions</a></li>
<li><a href="#p27">Mitigating Rubbish Truck Noise - A Case Study</a></li>
<li><a href="#p25">Effectiveness of acoustic lagging pipes in outdoor environments</a></li>
</ul>
<li>Session 6D: Entertainment Noise and Control</li>
<ul>
<li><a href="#p122">Beyond the Decibel - Managing Noise from Outdoor Concert Venues</a></li>
<li><a href="#p13">Entertainment Sound and Noise Controls for the amended City of Sydney DCP</a></li>
<li><a href="#p12">Outdoor Event Noise Monitoring - Lessons Learnt and Recommendations for Future Events</a></li>
<li><a href="#p102">Technical considerations in evaluating environmental noise from entertainment venues</a></li>
</ul>
<li>Session 6E: Architectural and Building Acoustics</li>
<ul>
<li><a href="#p106">Balancing Speech Privacy and Embodied Carbon Reduction in Building Design</a></li>
<li><a href="#p85">Acoustic Design for Queensland Ballet's Thomas Dixon Centre Refurbishment</a></li>
<li><a href="#p77">Predicting impulsive noise emission and compliance with AAAC gymnasium guideline criteria</a></li>
<li><a href="#p82">Comparative testing of Acoustic Isolation Properties of Mixed Cell Polyurethane (PUR) Elastomer in Lightweight Floating Floors</a></li>
</ul>
<li>Session 7A: Vibration</li>
<ul>
<li><a href="#p40">Vibration of a cantilever panel due to turbulence ingestion, part II: A virtual experiment</a></li>
<li><a href="#p39">Vibration of a cantilever panel due to turbulence ingestion, part I: A semi-analytical approach</a></li>
<li><a href="#p21">Radial vibration theory for thick-walled Hookean elastic hollow spheres with large strains and immersed in an incompressible fluid</a></li>
<li><a href="#p107">Noise and Health in children (in a broader environmental context)</a></li>
</ul>
<li>Session 7C: Architectural and Building Acoustics</li>
<ul>
<li><a href="#p17">The Study of an Innovative Sound Absorbing Mechanism for Low-Frequency Sound</a></li>
<li><a href="#p58">Acoustic testing of JBN Ceiling Speaker System installed in-situ.</a></li>
<li><a href="#p69">Sound masking system design and specification</a></li>
</ul>
<li>Session 7D: Instrumentation and Measurement</li>
<ul>
<li><a href="#p81">Design of an instrumented, modular insect arena for motion analysis and measuring ground reaction forces of small arthropods</a></li>
<li><a href="#p110">Comparison of data transmission protocols for remote and real-time environmental monitoring</a></li>
<li><a href="#p111">Review of audio compression formats for post-processing</a></li>
<li><a href="#p108">A microactuator device to mimic ant vibrations for termite deterrence on life plants</a></li>
<li><a href="#p56">Investigation of the Viability of Mobile Smartphones as Sound Level Meters</a></li>
</ul>
<li>Session 7E: Acoustic Design</li>
<ul>
<li><a href="#p80">Design of an anechoic termination for an open ended duct</a></li>
<li><a href="#p55">Innovative design of façade elements to limit wind-induced noise in buildings</a></li>
</ul>
<li>Plenary 1: Rebecca Dunlop
109 Hearing tests in Baleen whales</li>
<ul>
<li><a href="#p109">Hearing tests in baleen whales</a></li>
</ul>
<li>Plenary 2: Usama Kadri
121 Acoustic-gravity waves, theory and applications</li>
<ul>
<li><a href="#p121">Acoustic-Gravity Waves, Theory and Applications</a></li>
</ul>
<li>Plenary 3: Timothy Van Renterghem
23 Audio-visual interactions in environmental noise perception and the link to urban greening</li>
<ul>
<li><a href="#p23">Audio-visual interactions in environmental noise perception and the link to urban greening</a></li>
</ul>
</ul>
<ul id="Toc">
<ul>
<li>Aeroacoustics</li>
<ul>
<li><a href="#p66">Variation in acoustic radiation of a fluid-loaded cantilever excited by point or distributed force</a></li>
<li><a href="#p40">Vibration of a cantilever panel due to turbulence ingestion, part II: A virtual experiment</a></li>
<li><a href="#p39">Vibration of a cantilever panel due to turbulence ingestion, part I: A semi-analytical approach</a></li>
</ul>
<li>Architectural and Building Acoustics</li>
<ul>
<li><a href="#p88">Lessons in Education Building Design</a></li>
<li><a href="#p97">Novel prototype testing methods for vibration sensitive locations</a></li>
<li><a href="#p31">AI in Architectural Acoustics</a></li>
<li><a href="#p36">Vibration and Airborne Sound in Repurposed Buildings: A Case Study of a Drum Kit in a Music Classroom</a></li>
<li><a href="#p67">A Parametric Study of Sound Leakage Through Openings and Fittings</a></li>
<li><a href="#p86">Towards a Better Integration of Room Acoustic and Sound System Design for Multipurpose Venues</a></li>
<li><a href="#p85">Acoustic Design for Queensland Ballet's Thomas Dixon Centre Refurbishment</a></li>
<li><a href="#p61">Designing and Complying with the Acoustic Objectives for Metro Railway Stations.</a></li>
<li><a href="#p112">Design and Verification of a High-Performance Acoustic Testing Laboratory</a></li>
<li><a href="#p17">The Study of an Innovative Sound Absorbing Mechanism for Low-Frequency Sound</a></li>
<li><a href="#p123">Analysis of passive methods to provide noise attenuation for apartments with natural ventilation. Case Studies - Part 2</a></li>
<li><a href="#p96">Analysis of passive methods to provide noise attenuation for apartments with natural ventilation. Case Studies - Part 1</a></li>
<li><a href="#p77">Predicting impulsive noise emission and compliance with AAAC gymnasium guideline criteria</a></li>
<li><a href="#p13">Entertainment Sound and Noise Controls for the amended City of Sydney DCP</a></li>
<li><a href="#p49">A Comparative Assessment of Educational Acoustic Design Guidelines against NSW EFSG</a></li>
<li><a href="#p30">Considerations of External Noise and Vibration Factors in the Design of Sensitive Inpatient Facilities</a></li>
<li><a href="#p69">Sound masking system design and specification</a></li>
<li><a href="#p120">A Case for Review of PartF7 of NCC BCA</a></li>
<li><a href="#p2">Choral singers' perception of on-stage reverberance during an Australian tour</a></li>
</ul>
<li>Environmental Acoustics</li>
<ul>
<li><a href="#p98">Design and implementation of a masking system for tonal industrial noise emissions</a></li>
<li><a href="#p35">The Sonic Gathering Place Installation, Melbourne: User Experience and Post-Hoc Assessment of Sound Levels</a></li>
<li><a href="#p78">Open-cycle gas turbines: Predicting and controlling far-field noise</a></li>
<li><a href="#p60">Managing Construction Noise and Vibration Impacts by Risk Optimisation</a></li>
<li><a href="#p119">An economic workflow for training machine learning models to classify acoustic data</a></li>
<li><a href="#p70">Advancing AI-based Acoustic Classifiers for (Rail) Construction Noise</a></li>
<li><a href="#p103">Fairly assigning noise emission limits to new industrial precincts.</a></li>
<li><a href="#p37">Preventing sleep disturbance using a qualitative approach</a></li>
<li><a href="#p45">Considerations and strategies for cumulative industrial noise management using the NSW Noise Policy for Industry (NPfI)</a></li>
<li><a href="#p15">A framework for drone noise management in an Australian context</a></li>
<li><a href="#p10">Using a Monte Carlo simulation to account for source uncertainty in construction noise predictions</a></li>
<li><a href="#p29">Report review for consulting acousticians</a></li>
<li><a href="#p11">An audio dataset and hierarchical taxonomy for disaster scenes</a></li>
<li><a href="#p104">Noise assessment methodology for land-use planning</a></li>
<li><a href="#p113">Temperature Inversion Frequency From Sigma-Theta</a></li>
<li><a href="#p23">Audio-visual interactions in environmental noise perception and the link to urban greening</a></li>
<li><a href="#p12">Outdoor Event Noise Monitoring - Lessons Learnt and Recommendations for Future Events</a></li>
<li><a href="#p102">Technical considerations in evaluating environmental noise from entertainment venues</a></li>
</ul>
<li>Fundamental Acoustics</li>
<ul>
<li><a href="#p80">Design of an anechoic termination for an open ended duct</a></li>
<li><a href="#p66">Variation in acoustic radiation of a fluid-loaded cantilever excited by point or distributed force</a></li>
</ul>
<li>Instrumentation and Measurement Techniques</li>
<ul>
<li><a href="#p81">Design of an instrumented, modular insect arena for motion analysis and measuring ground reaction forces of small arthropods</a></li>
<li><a href="#p115">A practical modification to ISO 8297:1994 for unattended sound power level measurement of land drilling rigs.</a></li>
<li><a href="#p55">Innovative design of façade elements to limit wind-induced noise in buildings</a></li>
<li><a href="#p72">Detection of aircraft noise with a buried fibre-optic array</a></li>
<li><a href="#p111">Review of audio compression formats for post-processing</a></li>
<li><a href="#p110">Comparison of data transmission protocols for remote and real-time environmental monitoring</a></li>
<li><a href="#p108">A microactuator device to mimic ant vibrations for termite deterrence on life plants</a></li>
<li><a href="#p54">Denoising by neural network for muzzle blast detection</a></li>
<li><a href="#p56">Investigation of the Viability of Mobile Smartphones as Sound Level Meters</a></li>
</ul>
<li>Legislation and Standards</li>
<ul>
<li><a href="#p28">The Victorian Environment Reference Standard and how it has been considered and applied in noise assessments</a></li>
<li><a href="#p122">Beyond the Decibel - Managing Noise from Outdoor Concert Venues</a></li>
<li><a href="#p74">Assessing Noise Amenity Within the Context of an Occupational Noise Assessment</a></li>
</ul>
<li>Marine Bio-Acoustics</li>
<ul>
<li><a href="#p109">Hearing tests in baleen whales</a></li>
</ul>
<li>Musical Acoustics</li>
<ul>
<li><a href="#p87">A New Analysis of the Normal Modes of a Large English Church Bell</a></li>
</ul>
<li>Noise and Vibration Control</li>
<ul>
<li><a href="#p16">Noise Management Strategies: Large-Scale Solar BESS Projects in Australia</a></li>
<li><a href="#p68">Mitigation of Residential Air-Conditioning Condenser Noise</a></li>
<li><a href="#p27">Mitigating Rubbish Truck Noise - A Case Study</a></li>
<li><a href="#p25">Effectiveness of acoustic lagging pipes in outdoor environments</a></li>
<li><a href="#p58">Acoustic testing of JBN Ceiling Speaker System installed in-situ.</a></li>
<li><a href="#p82">Comparative testing of Acoustic Isolation Properties of Mixed Cell Polyurethane (PUR) Elastomer in Lightweight Floating Floors</a></li>
</ul>
<li>Occupational Health and Safety</li>
<ul>
<li><a href="#p74">Assessing Noise Amenity Within the Context of an Occupational Noise Assessment</a></li>
</ul>
<li>Physiological and Psychological Acoustics</li>
<ul>
<li><a href="#p100">Evidence-Based Interventions for Auditory Processing Issues in Individuals Who are Neurodiverse</a></li>
<li><a href="#p107">Noise and Health in children (in a broader environmental context)</a></li>
<li><a href="#p23">Audio-visual interactions in environmental noise perception and the link to urban greening</a></li>
<li><a href="#p76">The effect of white noise and "coloured" noise on cognition and sleep</a></li>
</ul>
<li>Rail Noise & Vibration</li>
<ul>
<li><a href="#p51">A screening method to predict indicative groundborne noise and vibration from light rail and heavy passenger rail and assess impacts for human comfort</a></li>
<li><a href="#p20">Validated airborne noise models of Perth metropolitan trains</a></li>
<li><a href="#p42">Vibration Criterion Curves - Part 2: Application to Transients</a></li>
<li><a href="#p41">Vibration Criterion Curves - Part 1: Evolution and Interpretation</a></li>
<li><a href="#p34">Railway Ground-Borne Noise in Terrace Houses: A Case Study</a></li>
<li><a href="#p83">Investigation into noise attenuation strategies within train tunnels</a></li>
</ul>
<li>Sound Quality and Reproduction</li>
<ul>
<li><a href="#p40">Vibration of a cantilever panel due to turbulence ingestion, part II: A virtual experiment</a></li>
</ul>
<li>Sustainability and Acoustics</li>
<ul>
<li><a href="#p106">Balancing Speech Privacy and Embodied Carbon Reduction in Building Design</a></li>
</ul>
<li>Transportation Noise</li>
<ul>
<li><a href="#p64">RONDA CPX Trailer Measurements of Heavily Degraded Open Graded Asphalt</a></li>
<li><a href="#p51">A screening method to predict indicative groundborne noise and vibration from light rail and heavy passenger rail and assess impacts for human comfort</a></li>
<li><a href="#p26">How Have NR Locomotive Noise Levels Changed Over Time?</a></li>
<li><a href="#p61">Designing and Complying with the Acoustic Objectives for Metro Railway Stations.</a></li>
</ul>
<li>Underwater Acoustics</li>
<ul>
<li><a href="#p52">The first study of ambient noise in Australia waters and how it influenced future work</a></li>
<li><a href="#p44">Exercises in Validating Shallow Water Pile Driving</a></li>
<li><a href="#p99">Developing geoacoustic seabed models for a shallow embayment with an elastic seafloor</a></li>
<li><a href="#p53">Bellhop Underwater Acoustic Simulation and Data Processing Optimisations: Getting Hi Def on the Desktop</a></li>
<li><a href="#p75">Measuring the frequency characteristic of underwater sound recorders ST500 and ST600 from Ocean Instruments</a></li>
<li><a href="#p66">Variation in acoustic radiation of a fluid-loaded cantilever excited by point or distributed force</a></li>
<li><a href="#p8">Weston α Description of Seafloor with Fast Fluid Layer over Basement Half-space</a></li>
<li><a href="#p121">Acoustic-Gravity Waves, Theory and Applications</a></li>
<li><a href="#p32">Underwater noise studies to support environmental impact assessment in Cockburn Sound, Western Australia</a></li>
<li><a href="#p89">Vibroacoustic response of a coated shell near a free sea surface</a></li>
<li><a href="#p91">Transition from perturbation to Kirchhoff approximation for modelling coherent reflection of underwater sound from rough sea surfaces</a></li>
</ul>
<li>Vibration</li>
<ul>
<li><a href="#p14">Footfall vibration on a high frequency walkway.</a></li>
<li><a href="#p40">Vibration of a cantilever panel due to turbulence ingestion, part II: A virtual experiment</a></li>
<li><a href="#p39">Vibration of a cantilever panel due to turbulence ingestion, part I: A semi-analytical approach</a></li>
<li><a href="#p118">Experimental vibration analysis of a beam with ABH stiffeners</a></li>
<li><a href="#p21">Radial vibration theory for thick-walled Hookean elastic hollow spheres with large strains and immersed in an incompressible fluid</a></li>
<li><a href="#p19">Advanced Analysis of Ground-Borne Vibration Noise Impacts for Underground Railway Tunnel Construction</a></li>
<li><a href="#p42">Vibration Criterion Curves - Part 2: Application to Transients</a></li>
<li><a href="#p41">Vibration Criterion Curves - Part 1: Evolution and Interpretation</a></li>
<li><a href="#p65">Coupling of Circumferential Modes in a Circular Plate</a></li>
<li><a href="#p6">Human-Induced Vibrations on Lightweight Footbridges</a></li>
</ul>
<li>Wind Turbines and Low Frequency Noise</li>
<ul>
<li><a href="#p114">An Approach to Compare Amplitude Modulation Depth and Penalty Schemes for Wind Farms</a></li>
<li><a href="#p117">Modeling Low-Frequency Sound Propagation in a Ducted Atmosphere Using a Semi-Analytic Finite Element Method</a></li>
<li><a href="#p7">Evaluating Noise Criteria for Wind Farms: A Comparison of Background Noise Curve Fitting and Wind Speed Bin Data Post-Processing</a></li>
</ul>
</ul>
</ul>
<hr>
<h4 style="text-align: center;">All rights reserved. Permission is granted for any person to reproduce a part of any abstract provided that the permission is obtained from the author(s) and credit is given to the author(s) and these conference proceedings.</h4>
<hr>
<h2><a name="p19" class="affilation"></a>Advanced Analysis of Ground-Borne Vibration Noise Impacts for Underground Railway Tunnel Construction</h2>
<h3>Menon, Vyshakh (1), Miller, Aaron (1), Hanson, David (1), Parnell, Jeffrey (2)</h3>
<p class="affilation">(1) Acoustic Studio, Sydney, Australia
(2) Sydney Metro, Sydney, Australia</p>
<p><b>ABSTRACT</b><br>
This paper analyses ground-borne noise and vibration generated from tunnel boring machines (TBMs) and cross-passage excavation activities associated with tunnelling in the Sydney region. While much literature for TBMs and excavation activities is available from overseas sources with respect to peak particle velocity (PPV), this is usually limited to the relatively short setback distances applicable to structural damage concerns. This study presents PPVs, A-weighted ground-borne RMS vibration levels and one-third octave band spectra from TBMs and cross-passage excavation activities at various offset distances in the ground, out to distances of 300 m, that may be applicable to ground-borne noise or even sensitive equipment concerns. This data should inform future predictions of vibration and ground-borne noise impacts on other tunnelling and excavation projects in the Sydney region.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p19.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p87" class="affilation"></a>A New Analysis of the Normal Modes of a Large English Church Bell</h2>
<h3>Whyte, Hamish (1), Perrin, Robert (1), Halkon, Benjamin (1)</h3>
<p class="affilation">(1) UTS</p>
<p><b>ABSTRACT</b><br>
The present paper reports on the use of a modern "state-of-the-art" FE package to re-examine the normal modes of a large (2.41 kg) English church bell which first appeared in 1983. ABAQUS produced results in close agreement with experiment but, with its enhanced visualisation and post-processing capabilities, a more complete understanding of mode shapes that have previously been difficult to analyse, became possible. The ability to include superimposed deformation vectors in the visualisation of modes enabled them to be classified into three categories: those with predominantly (1) radial, (2) longitudinal and (3) tangential deformations, respectively. Resolving mode shape deformations into these directions, has allowed quantitative confirmation of the classifications. Relationships between the ratios of the deformation components and the symmetry properties of the modes are presented. The results are largely in line with expectations, including those derived from studies of the vibrations of cylinders and from group representation theory.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p87.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p96" class="affilation"></a>Analysis of passive methods to provide noise attenuation for apartments with natural ventilation. Case Studies - Part 1</h2>
<h3>Leembruggen, Glenn (1), Parry-Jones, Joel (2)</h3>
<p class="affilation">(1) Acoustic Directions
(2) PKA Acoustic Consulting</p>
<p><b>ABSTRACT</b><br>
The NSW Apartment Design Guide mandates that a percentage of apartments in a development have natural cross ventilation. In areas nears busy roads, the need to provide this ventilation whilst maintaining low internal noise levels from the ingress of traffic provides a difficult challenge of acoustic engineers. The authors recently undertook a detailed investigation for the City of Sydney into the attenuations that are available with a range of passive devices that can be used to provide natural ventilation in apartments. For the attenuation methods in which wave acoustics were dominant, predications of attenuations were made using finite element analysis, while in the remaining situations, sophisticated ray-tracing software was used. Among the attenuation devices explored were i) balcony areas with varying sound absorption linings which feed into absorptive ventilation ducts, ii) louvred apertures with absorption, iii) open wintergardens, iv) gradual setbacks of balconies, v) shielding structures and vi) open windows into various sized apartments. The attenuations of each method can be combined (with appropriate conversions to sound power) to produce a net outside-to-inside attenuation of sound pressure level. The project won the H. Vivian Taylor Award for excellence from the Association of Australasian Acoustical Consultants in 2021.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p96.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p123" class="affilation"></a>Analysis of passive methods to provide noise attenuation for apartments with natural ventilation. Case Studies - Part 2</h2>
<h3>Leembruggen, Glenn (1), Parry-Jones, Joel (2)</h3>
<p class="affilation">(1) Acoustic Directions
(2) PKA Acoustic Consulting</p>
<p><b>ABSTRACT</b><br>
The NSW Apartment Design Guide mandates that a percentage of apartments in a development have natural cross ventilation. In areas nears busy roads, the need to provide this ventilation whilst maintaining low internal noise levels from the ingress of traffic provides a difficult challenge of acoustic engineers. The authors recently undertook a detailed investigation for the City of Sydney into the attenuations that are available with a range of passive devices that can be used to provide natural ventilation in apartments. For the attenuation methods in which wave acoustics were dominant, predications of attenuations were made using finite element analysis, while in the remaining situations, sophisticated ray-tracing software was used. Among the attenuation devices explored were i) balcony areas with varying sound absorption linings which feed into absorptive ventilation ducts, ii) louvred apertures with absorption, iii) open wintergardens, iv) gradual setbacks of balconies, v) shielding structures and vi) open windows into various sized apartments. The attenuations of each method can be combined (with appropriate conversions to sound power) to produce a net outside-to-inside attenuation of sound pressure level. The project won the H. Vivian Taylor Award for excellence from the Association of Australasian Acoustical Consultants in 2021.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p123.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p114" class="affilation"></a>An Approach to Compare Amplitude Modulation Depth and Penalty Schemes for Wind Farms</h2>
<h3>Bruck, Matthew (1), Gustaf, Reutersward (1)</h3>
<p class="affilation">(1) SLR Consulting Pty Ltd</p>
<p><b>ABSTRACT</b><br>
There is agreement among relevant wind farm standards and government guidelines that Amplitude Modulation (AM) from wind farms beyond a normal degree of fluctuation typical for horizontal axis wind turbines should have a special audible characteristic penalty applied. However, more than one method exists for establishing the level of AM depth and for determining the applied penalty. This causes challenges when methods of calculating AM depth and multiple penalty schemes make their way into consent conditions. The two schemes compared for this study were 1) New Zealand Standard NZS 6808:2010, which provides an interim method to identify periods of amplitude modulation depth and an associated +5 dB penalty if discovered; and 2) The UK Institute of Acoustics (IoA) Amplitude Modulation Working Group (AMWG) method described in Final Report - A Method for Rating Amplitude Modulation in Wind Turbine Noise Version 1 (2016). The method to compare the schemes was to run the AMWG algorithm over the reference noise metrics described in NZS6808 (one-third octave band with greatest AM depth and overall Leq level) and then conduct a linear regression on these results against the AM depth results from a strict AMWG interpretation using the relevant frequency band (100 Hz - 400 Hz).<br>
<br>
Analysis of monitoring data of a wind farm for the purposes of this study found that an AM depth of approximately 4.4 dB calculated using a strict interpretation of the AMWG method approached maximum equivalency to the method described in NZS 6808:2010. The methodology of the assessment and obtained outcomes, along with implications on wind farm projects is detailed in this study.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p114.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p7" class="affilation"></a>Evaluating Noise Criteria for Wind Farms: A Comparison of Background Noise Curve Fitting and Wind Speed Bin Data Post-Processing</h2>
<h3>Lenchine, Valeri V.</h3>
<p class="affilation">GHD Pty Ltd</p>
<p><b>ABSTRACT</b><br>
In the realm of renewable energy development, the assessment of noise impact from wind farms is a critical aspect of both planning approval and compliance checking. Across Australian jurisdictions, this assessment typically adheres to established guidelines. The noise criteria applicable at noise-sensitive receivers are based on baseline levels or a 'background + 5 dB(A)' rule. <br>
<br>
Historically, the background noise level at a specific hub height wind speed has been derived using a curve fitting process. This process involves the analysis of a large dataset of background noise measurements. The curve fitting method provides a statistical model of the background noise, which is then used to establish the noise criteria for the wind farm.<br>
<br>
This paper examines the impact of amendments to the South Australian wind farm noise guidelines on the assessment of noise impact from wind farms. The 2021 amendments introduced an alternative method for post-processing background noise data in wind speed bins, aligning with the IEC 64100-11 standard for reporting the apparent sound power level of turbines.<br>
<br>
This paper presents a comparative study between the superseded guidelines and the updated procedure, focusing on the post-processing of background noise data. Our case studies reveal that the estimates of background noise in the wind speed range typically used for wind farm noise assessment, show insignificant variation between the two methods. Consequently, the resultant noise criteria derived from these estimates are also similar, irrespective of the post-processing procedure employed.<br>
<br>
These findings suggest that noise criteria based on historical background noise measurements may remain applicable under the new guidelines.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p7.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p60" class="affilation"></a>Managing Construction Noise and Vibration Impacts by Risk Optimisation</h2>
<h3>Davis, Dave</h3>
<p class="affilation">Jacobs Group Australia Pty Ltd</p>
<p><b>ABSTRACT</b><br>
Environmental noise and vibration from construction sites represents a considerable environmental risk to large engineering projects. Mitigating and managing the environmental impact and loss of amenity for nearby communities can result in significant project costs and delays, both of which the Principal Contractor would typically desire to be minimised or avoided if possible. When viewed from a financial perspective, the requirement to manage environmental noise and vibration impacts is a type of risk exposure for the project since the environmental management obligations consist of a number of committed and potential costs, each with a degree of uncertainty. This paper discusses an approach that a contractor may use to estimate the project's budget to manage noise and vibration from construction works by considering the likelihood and consequence of incurring direct and indirect costs associated with noise and vibration impacts. Any of these items in the project's construction budget that are quantified in terms of costs weighted by probability and/or uncertainty can then be included in the risk optimisation part of the tender pricing calculations. In terms of a project's overall environmental management obligations, the method described herein would be complementary to existing processes such as the standard practice of preparing and implementing construction noise and vibration management plans.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p60.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p10" class="affilation"></a>Using a Monte Carlo simulation to account for source uncertainty in construction noise predictions</h2>
<h3>Morris, Adrian (1), Tabacchi, Mattia (1)</h3>
<p class="affilation">(1) Renzo Tonin & Associates</p>
<p><b>ABSTRACT</b><br>
Noise modelling aims to quantify the potential noise impacts of construction works at neighbouring noise-sensitive receivers. In Australia, particularly in New South Wales, quantitative noise assessments need to present the realistic worst-case or conservative scenario that may be encountered during the project. This approach results in a reporting of substantial noise impacts, particularly when a worst-case assumption is made for each noise input. Across multiple construction projects in New South Wales, it was found that these realistic worst-case noise predictions are substantially higher than the actual levels recorded during verification measurements. To improve alignment between predictions and measurements, noise modelling results are included in a Monte Carlo simulation that considers input probabilities derived from site observations.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p10.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p51" class="affilation"></a>A screening method to predict indicative groundborne noise and vibration from light rail and heavy passenger rail and assess impacts for human comfort</h2>
<h3>Davis, Dave</h3>
<p class="affilation">Jacobs Group Australia Pty Ltd</p>
<p><b>ABSTRACT</b><br>
Preliminary environmental impact assessments of rail transport projects may require prediction of indicative groundborne vibration and/or groundborne noise (GBNV) levels within nearby receiver buildings. Methods commonly used to predict GBNV generally require relatively accurate information for the vibration source(s), the intervening ground conditions and the receiver building(s). This paper provides a simple method to predict a conservative estimate of GBNV levels from light rail transit and heavy passenger rail transport vehicles in nearby receiver buildings, and provides approximate buffer zones for typical assessment thresholds.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p51.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p20" class="affilation"></a>Validated airborne noise models of Perth metropolitan trains</h2>
<h3>Liu, Ying (1), Zoontjens, Luke</h3>
<p class="affilation">(1) SLR Consulting Australia Pty Ltd</p>
<p><b>ABSTRACT</b><br>
Railway noise prediction methods such as Kilde 130, Nord 2000, and CNOSSOS-EU are popular and all continue to be used in professional practice. However, these methodologies require validation to suit local scenarios. <br>
<br>
In Western Australia, specific adjustments are required for accurately represent railway noise emissions because of its specific combination of vehicle types, track configurations, and environmental features.<br>
<br>
To address this, comprehensive railway noise measurements undertaken across various sites in Western Australia have been used to validate input settings for each prediction method to assist with future studies. <br>
<br>
This paper will detail the methodology employed in the calibration process, including the specific adjustments made to each prediction method and the validation against field measurements. <br>
<br>
The results demonstrate significant improvements in the precision of noise predictions between each generation of model. The calibrated models provided a closer match to the actual railway noise levels experienced, thereby supporting better decision-making in railway infrastructure projects, and improved certainty in outcomes.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p20.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p34" class="affilation"></a>Railway Ground-Borne Noise in Terrace Houses: A Case Study</h2>
<h3>Miller, Aaron (1), Hanson, David (1), Menon, Vyshakh (1)</h3>
<p class="affilation">(1) Acoustic Studio Pty Ltd</p>
<p><b>ABSTRACT</b><br>
Ground-borne noise impact assessments often concentrate on the front room of affected properties and assume that noise levels are lower elsewhere. This paper reports on a case study that examined this assumption, exploring how ground-borne noise and vibration varied throughout a two-storey terrace house above a rail tunnel in Sydney. Simultaneous measurements of noise and vibration were recorded in front and rear rooms, on both the ground and first floors, during train passes. An additional measurement was recorded on the ground in front of the house to allow coupling loss to be determined. This paper presents the ground-borne noise and vibration levels throughout the house, examines the effectiveness of the common vibration-to-noise estimation method, and compares measured noise levels with those estimated using the popular Federal Transit Authority (FTA) method. The results may be used to inform future ground-borne noise assessments for underground railways.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p34.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p83" class="affilation"></a>Investigation into noise attenuation strategies within train tunnels</h2>
<h3>Williams, Paul (1), Karimi, Mahmoud (1), Sepehrirahnama, Shahrokh (2), Reverter Garcia, Jorge (2), Croft, Briony (3), Hanson, David (3), Miller, Aaron (3), Parnell, Jeffrey (4)</h3>
<p class="affilation">(1) Centre for Audio, Acoustics, and Vibration, University of Technology Sydney, Ultimo, New South Wales, Australia
(2) JHA Consulting Engineers, Sydney, New South Wales, Australia
(3) Acoustic Studio Pty Ltd, Stanmore, New South Wales, Australia
(4) Sydney Metro, New South Wales, Australia</p>
<p><b>ABSTRACT</b><br>
Across Australia, cities are extending their public transportation systems through additional tunnels and metro systems. The sound energy generated by metro trains operating in tunnels is mainly confined within the tunnel by the tunnel walls, causing higher noise levels within the carriages than comparable above-ground networks. This work investigates in-tunnel noise using a computational model of the metro tunnel, with the objective of developing a tool that can be used to investigate a range of novel mitigation measures. A numerical model is developed that uses the semi-analytical finite element (SAFE) method to provide a novel modal-based approach towards tunnel noise modelling. The first stage of this method involves performing a two-dimensional finite element eigenvalue decomposition over the cross-section of the tunnel to determine the characteristics of each tunnel mode. Propagation of sound pressure along the length of the tunnel is then implemented analytically, avoiding the computational expense of three-dimensional standard finite element methods. For simplicity, the carriage can be included as a rigid body, and the variations of the tunnel cross-section are neglected. Predictions are compared to the measured in-tunnel noise generated using a known input source. Numerical and experimental studies will allow for the investigation of cost-effective noise reduction solutions that may be applied to current and future rail projects.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p83.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p31" class="affilation"></a>AI in Architectural Acoustics</h2>
<h3>Foster, Alex, James, Deb</h3>
<p><b>ABSTRACT</b><br>
This paper explores a potential framework for applying Artificial Intelligence (AI) in acoustic consulting, focusing on the automated analysis of architectural drawings to determine key project criteria. Acoustic consultants currently typically rely on visual interpretation of architectural drawings to establish criteria for internal noise levels, reverberation time, and acoustic separation, which can be both time consuming and error prone. The proposed AI framework aims to automate this process by using computer vision and machine learning techniques to identify and extract relevant features, such as room names, room layouts, as well as architectural elements such as doors, glazing, partitions, and finishes. By leveraging these technologies, the framework seeks to enhance the efficiency, accuracy, and consistency of acoustic analysis, enabling consultants to make more informed decisions. The paper discusses the components of this framework, the potential benefits and challenges of its implementation, and suggests proof-of-concept tests to validate its effectiveness.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p31.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p119" class="affilation"></a>An economic workflow for training machine learning models to classify acoustic data</h2>
<h3>Glorie, Peter (1), Shehnepoor, Saeed (1)</h3>
<p class="affilation">(1) Wood PLC</p>
<p><b>ABSTRACT</b><br>
Abstract - The increasing popularity and availability of AI has accelerated the development of machine learning based solutions for analysis of acoustic monitoring data. Machine Learning has been demonstrated to be effective in multiple applications including environmental noise monitoring and determining contributions to worker noise exposure. However, there is a significant cost to create effective models, due to the large data labelling requirement, iterative approach, specialist skills and tools required to review data for labelling or output performance.<br>
<br>
While ML methods have been found to add value to large-scale or long-term monitoring programs (e.g. for above ground mining operations), applying ML to shorter term data sets (e.g. short term construction) may not be economic due to the time and specialist skills required to develop an effective model. A significantly less labour-intensive development process would unlock the benefits of ML analysis for a broader range of use cases in industry.<br>
<br>
This paper presents a workflow solution that bridges the gap between data science and acoustics, empowering users to harness the power of AI and analyse large data sets, without requiring coding or data science skills. The solution broadens the applications for ML analysis of acoustic data in industry by enabling accurate ML models to be developed much more efficiently. <br>
<br>
This paper will outline how an acoustician can efficiently create accurate ML models that classify large and complex acoustic data.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p119.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p70" class="affilation"></a>Advancing AI-based Acoustic Classifiers for (Rail) Construction Noise</h2>
<h3>Halkon, Benjamin (1), Darroch, Michael (2), Cooper-Woolley, Ben (2), Zhao, Sipei (1), Miller, Aaron (3), Hanson, David (3), Marrinan, Matthew (4), Hendy, Andrew (4), Parnell, Jeffrey (4), Mifsud, Stephanie (5)</h3>
<p class="affilation">(1) UTS
(2) SiteHive
(3) Acoustic Studio
(4) Sydney Metro
(5) Gamuda Laing O'Rourke Consortium</p>
<p><b>ABSTRACT</b><br>
Recent advances in AI technology have lowered the barrier to entry and cost of ownership of Internet-of-Things (IoT) related sensing. This may present opportunities to supplement or replace the current approaches for construction noise management with dynamic, real-time systems which can provide direct feedback to site managers. Improvements in noise predictions and better real-time tools will also convey strong benefits to surrounding impacted communities. In this paper, a recent pilot project, which aimed to establish that AI is suited to airborne noise data analysis and predictive capability and can be improved with increasing training data in the context of construction noise, will be described. Existing technology developed by SiteHive, which can predict noise sources from audio recordings, was deployed on Sydney Metro construction sites with audio gathered from a number of typical activities. Using accepted measurements of AI model accuracy, it is demonstrated that the Audio Classifier (AC) was able to increase its predictive accuracy from 29% to 81%, within 14 shortlisted classes comprising 10 construction and four non-construction categories. A strong predictive capability and rapid learning with increased body of training data demonstrate the potential of the AC in this and other applications in environmental acoustics.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p70.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p11" class="affilation"></a>An audio dataset and hierarchical taxonomy for disaster scenes</h2>
<h3>Pham, Tuan-Anh (1), Park, Seonghun (1), Lee, Jong-Hoon (1), Han, Sang-Jin (1), Choi, Jungyu (2), Im, Sungbin (2)</h3>
<p class="affilation">(1) Department of AI Laboratory, MOADATA, Gyeonggi, South Korea
(2) Soongsil University, Seoul, South Korea</p>
<p><b>ABSTRACT</b><br>
In the aftermath of disasters, timely response and rescue operations are crucial for saving lives. However, the post-disaster environment often presents challenges such as structural damage, debris, and hazardous conditions, where visual cues are obstructed or unavailable. In such situations, effective analysis of audio data can provide critical insights and situational awareness to guide response efforts. However, existing audio datasets for disaster scenarios are limited and lack a comprehensive taxonomy to represent the diverse sound events encountered in these environments. In this paper, we present an audio dataset specifically curated for disaster scenes along with a hierarchical taxonomy to categorize possible related sound events. The audio dataset comprises audio clips organized into 31 event categories. The first 30 categories each contain 50 audio clips, while the remaining category contains 1,000 clips. To augment this dataset, we leverage a generative model AudioLDM to synthesize an additional 1,000 audio samples for each event category. Instead of relying on text prompts, we employ 50 reference clips from each category as the condition input to generate target audio samples, resulting in a total of 30,000 samples. To select high-fidelity generated samples, we propose a simple two-stage process that combines the Frechet Audio Distance (FAD) metric and a finetuned pretrained audio model PANNs. To verify the effectiveness of the audio selection process, we randomly selected 100 audio clips from the generated data, finetune PANNs, and classify the reference audio clips. The finetuned PANNs achieves 89.27% in top-1 accuracy and 95.99% in top-2 accuracy.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p11.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p86" class="affilation"></a>Towards a Better Integration of Room Acoustic and Sound System Design for Multipurpose Venues</h2>
<h3>Heddle, James</h3>
<p class="affilation">-</p>
<p><b>ABSTRACT</b><br>
A recent landmark performance space experienced a subpar outcome for the installed sound system. Based on the changes that made a successful improvement to the sound and psychoacoustic aspects of room acoustic design, this paper attempts to outline desirable traits for sound systems that should be considered within the context of the acoustic and overall design during the collaborative design process.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p86.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p120" class="affilation"></a>A Case for Review of PartF7 of NCC BCA</h2>
<h3>Temelkoski, Sasho (1), Todorovski, Bojan (1), Thompson, Bradley (1)</h3>
<p class="affilation">(1) ATP Consulting Engineers</p>
<p><b>ABSTRACT</b><br>
This paper presents examples of the legacy sound transmission issues, inherited from the poor sound insulation requirements for walls and floors as applicable in Queensland up to 2009. Lessons learned from application of the requirements for sound insulation from BCA 2009 onwards, are also presented. Propositions for amendments to some of the sound insulation ratings for floors and walls are provided as a contribution towards discussion on the improvement of the sound insulation requirements in the next edition of NCC BCA.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p120.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p2" class="affilation"></a>Choral singers' perception of on-stage reverberance during an Australian tour</h2>
<h3>Zhang, Maggie M.</h3>
<p class="affilation">Marshall Day Acoustics, Auckland</p>
<p><b>ABSTRACT</b><br>
Choral singers on stage may experience the acoustics of performance spaces differently to what is perceived by the conductor or the audience. The New Zealand Youth Choir (NZYC) embarked on a tour of Australia in November and December of 2022, which presented an opportunity to conduct studies on singers' response to room acoustics. The study aimed to determine the influence of stage acoustic effects on choral singers' perception. The methodology included surveying the members of the choir after performances, and conducting acoustic measurements in the stage area. Surveys for ten venues were gathered, supported by measurements of eight venues. The venues included neo-Gothic churches, multi-purpose auditoriums and the Sydney Opera House Concert Hall. Statistical analysis of the results reinforced the understanding of singer sensitivity to and preference for spaces with relatively high reverberance, with little influence by the room volume.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p2.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p52" class="affilation"></a>The first study of ambient noise in Australia waters and how it influenced future work</h2>
<h3>Cato, Douglas H</h3>
<p class="affilation">School of Geosciences, University of Sydney</p>
<p><b>ABSTRACT</b><br>
The first experimental study of ambient noise in waters near Australia was in the Timor Sea north of Darwin in 1966 and was conducted by the Royal Australian Navy Research Laboratory. There had been underwater acoustic studies by the same laboratory before then but these had not considered the ambient noise. The Timor Sea ambient noise (the background noise) and the soundscapes (all sounds in the environment) were so different to what was expected from studies in other parts of the world that it changed our view of ambient noise and it significantly influenced the design of the many Australian studies that followed over the years. The noise and the soundscapes were dominated by biological sounds. Traffic noise was absent because of the poor propagation and scarcity of shipping, and low wind speeds during the periods of measurement ensured that wind-dependent noise was very low. The only high level non-biological noise was from the impact of rain during occasional tropical storms and occasional surf noise. Several quite unusual and aurally striking biological sounds were present throughout the recordings. These were later determined to be generated by fish but initially there was considerable concern that they might have been artefacts of the inhouse equipment used. The most unusual effects, however, were the high level biological choruses that occurred for three or so hours at a time just after dusk, before dawn and sometimes around midday. Sea noise prediction curves at the time did not include biological noise (many still do not), yet here was a site where the noise was predominantly biological and included choruses that were around 20 dB higher than typical background noise. Was this a peculiarity of the area or were these choruses more widespread? It turned out from further studies in the Indian and Pacific Oceans in the Australian region that choruses are widespread features of ambient noise. This presentation will describe some of the challenges we faced in early recording and analysis of underwater sounds in the pre-digital age. It will describe what we found and place it in context with what was known at the time from Northern Hemisphere studies and how this influenced future ambient noise research. It is interesting to contemplate how different subsequent studies might have been if we had chosen a site that was more typical of northern hemisphere ambient noise.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p52.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p44" class="affilation"></a>Exercises in Validating Shallow Water Pile Driving</h2>
<h3>Connell, Steven (1), Koessler, Matthew (2), McPherson, Craig</h3>
<p class="affilation">(1) JASCO Applied Scienes Australia
(2) JASCO Applied Scienes Canada</p>
<p><b>ABSTRACT</b><br>
Piles driven into the seabed with impact hammers are commonplace for marine construction, however, may carry the potential to impact marine fauna. Underwater modelling is an important tool for predicting environmental effect ranges for marine fauna. In this study we modelled and measured the sound field and subsequent impact ranges for construction activities involving marine pile installation using an impact hammer. In-field measurements of the received levels used a stationary JASCO AMAR (Autonomous Multi-channel Acoustic Recorder) and a drift measurement using a JASCO Ocean Sound Meter 2. The same scenario was modelled and compared with the measurement data. Verification and refinement of the modelled sound fields was be achieved by comparison to measured results. The accuracy of modelling relies on the quality of the inputs for the environmental and source parameters and associated approximations made due to lack of information or computation constraints. By improving the modelling, more accurate predictions can be made for impact ranges to marine fauna.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p44.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p8" class="affilation"></a>Weston α Description of Seafloor with Fast Fluid Layer over Basement Half-space</h2>
<h3>Jones, Adrian D</h3>
<p class="affilation">Ocean Acoustics Associates</p>
<p><b>ABSTRACT</b><br>
For sound incident at a seafloor at angles less than the critical angle, the Weston α parameter (Weston, D. E., J. Sound Vib. 18, 271-287, 1971) provides a good estimate of the slope of bottom loss in dB versus grazing angle for small angles. Formulae for the Weston α parameter, in terms of the seafloor geoacoustic properties, have been determined for uniform half-space seafloor types. This paper considers the Weston α parameter for a seafloor consisting of a uniform fast fluid layer over a uniform basement. In this initial segment of work, an analytic solution is obtained for a loss-less fluid layer over an elastic basement for which the shear speed is less than the seawater sound speed. Values of bottom loss obtained from this solution are compared with some existing computations available from the literature. The solution is sufficiently simple to permit hand calculations, plus it clarifies the dependence of bottom loss on the parameters of the layered seafloor, in particularly, the thickness of the fluid layer. Limitations to the solution are considered.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p8.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p32" class="affilation"></a>Underwater noise studies to support environmental impact assessment in Cockburn Sound, Western Australia</h2>
<h3>Parnum, Iain (1), Duncan, Alec D. (1), Tollefsen, Cristina (1), Wei, Chong (1), Erbe, Christine (1)</h3>
<p class="affilation">(1) CMST, Curtin University</p>
<p><b>ABSTRACT</b><br>
A coordinated program of underwater noise studies in Cockburn Sound, Western Australia, was carried out between September 2022 and December 2023. These studies were part of the Western Australian Marine Science Institution's Westport Marine Science Program, which is designed to improve the capacity to avoid, mitigate, and offset environmental impacts of new developments in Cockburn Sound. This project included measurements to help improve knowledge of the baseline underwater soundscapes, sound propagation, source levels of vessels and port activities, and hearing sensitivity of key marine fauna of Cockburn Sound. The underwater soundscape of Cockburn Sound was found to contain geophony (e.g., wind), anthropophony (vessels and machinery), and biophony (dolphins, fish, and snapping shrimp) sources. Hearing sensitivity of Little Penguins and Australian Sea Lions was modelled based on anatomical information from stranded and deceased specimens. Sound propagation, in particular from the port and ships, was measured and modelled, and the susceptibility of key species to the range of frequencies emitted by vessels and port operations investigated. The findings will be used to develop mitigation methods for the potential effects of underwater noise on marine species.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p32.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p64" class="affilation"></a>RONDA CPX Trailer Measurements of Heavily Degraded Open Graded Asphalt</h2>
<h3>Chung, Michael (1), Chan, William (1), Sundar, Aakash (1), Fricker, Ima (2), Angliss, Allan (2), Stevens, Ash (2)</h3>
<p class="affilation">(1) Renzo Tonin & Associates NSW Pty Ltd
(2) WSP and Eastern BTA</p>
<p><b>ABSTRACT</b><br>
RONDA (ROad Noise Data Acquirer) is a CPX trailer conforming to ISO/CD 11819-2 for the measurement of tyre-pavement noise. The trailer is of the open frame type without an enclosure. Tyre-pavement noise measurements along a major freeway in Melbourne were recently undertaken to quantify noise levels of old and dilapidated low noise pavements along sections of the freeway, which includes open graded asphalt (OGA). Measurement data was analysed to determine the tyre-pavement noise levels for the old OGA pavement. It was found that the old and dilapidated OGA pavement did not provide the noise benefits expected of low noise pavements and the tyre-pavement noise levels were in fact higher than the reference tyre-pavement noise level.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p64.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p26" class="affilation"></a>How Have NR Locomotive Noise Levels Changed Over Time?</h2>
<h3>Hanson, David (1), Pandey, Pri (2), Flint, Kate (3)</h3>
<p class="affilation">(1) Acoustic Studio
(2) GHD
(3) Pacific National</p>
<p><b>ABSTRACT</b><br>
Since mid-2020 when new Environment Protection Licenses (EPLs) were introduced, Pacific National has conducted noise tests on each locomotive following major engine overhaul. Pacific National has thus developed an unprecedented database of locomotive noise levels, with results from standardised noise tests on approximately 100 locomotives across six locomotive classes. Some of these locomotive classes have been in service for more than 25 years. The scale and quality of this database allows fundamental questions about locomotive noise to be explored. In this paper we discuss how locomotive noise has changed over time by comparing the noise levels of the NR Class locomotive when it was first introduced in the late 1990s with its noise emissions today. We also compare the noise emissions recorded trackside in revenue service with those captured in the standardised stationary tests, to better inform how locomotive noise is modelled and impacts predicted.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p26.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p78" class="affilation"></a>Open-cycle gas turbines: Predicting and controlling far-field noise</h2>
<h3>Cazzolato, Ben</h3>
<p><b>ABSTRACT</b><br>
With exhaust sound power levels often exceeding 150 dB re 1pW, temperatures between 550-650 degrees C, and high flow rates, the mitigation of the noise from large gas turbines used in simple and combined-cycle power stations present a challenge to acoustic engineers, especially under certain atmospheric conditions. This paper presents the research conducted at The University of Adelaide over the last decade on the mechanisms of sound radiation from hot exhausts, how this is affected by local atmospheric conditions as it propagates to the far-field, and potential methods for attenuating this noise. It will be shown that in unfavourable conditions, the sound pressure levels at a nearby community can be 10dB higher than predicted by commonly used models/standards. However, with the installation of a compact device, this increase in far-field noise can be mostly mitigated. The paper includes results from field measurements near power stations, numerical modelling, small-scale laboratory experiments and recent medium-scale field trials.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p78.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p68" class="affilation"></a>Mitigation of Residential Air-Conditioning Condenser Noise</h2>
<h3>Hayne, Michael (1), Devereux, Richard (2)</h3>
<p class="affilation">(1) SoundBASE Consulting Engineers
(2) Acran Sound Control</p>
<p><b>ABSTRACT</b><br>
The mitigation of residential air-conditioning condenser noise can be a very difficult problem to solve. Often situated at the side or rear of residences where there is limited access and low background noise levels, it is necessary to engineer a solution that achieves a noise reduction in excess of 30dB. Finding an acoustician or specialist contractor to mitigate the noise can be difficult, as the design requirements for residential air-conditioning condensers are usually stricter than those of commercial air-conditioning condensers, with the solution being expensive compared to the original cost of the air-conditioning system. In this paper, the factors influencing residential air-conditioning condensers noise control are discussed to allow an engineering design methodology to be derived. In addition, alternative approaches that could potentially be used by residents and local authorities to manage residential air-conditioning condenser noise without implementing expensive noise control measures are presented.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p68.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p36" class="affilation"></a>Vibration and Airborne Sound in Repurposed Buildings: A Case Study of a Drum Kit in a Music Classroom</h2>
<h3>Gjers, Emma Linnea</h3>
<p class="affilation">WSP Australia Pty Limited</p>
<p><b>ABSTRACT</b><br>
This paper presents a case study of a space in a commercial building that was to be converted into a music classroom within a secondary school. Music classrooms, especially at the higher education level, often contain amplified or loud instruments, including acoustic percussion such as drums. Drums pose unique challenges due to the generation of both high airborne sound pressure levels and induced structural vibrations. Vibration and airborne sound from three critical drum components were measured to assess transmission through a suspended concrete slab and connecting masonry elements. The impact of using a resilient interlayer to reduce structural vibration and re-radiated noise was also evaluated. The tested resilient platform reduced airborne and structure-borne sound by approximately 5 dB in Dw measurements, particularly for the thinner slab. The study underscores the complexity of sound transmission in buildings, suggesting the need for further investigation. The results of these measurements for various slab thicknesses and mitigation strategies offer insights for treating airborne noise and structural vibration in drum kits and other loud instruments.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p36.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p61" class="affilation"></a>Designing and Complying with the Acoustic Objectives for Metro Railway Stations.</h2>
<h3>Krikke, Tom (1), Brown, Graham (1), Parnell, Jeffrey (2)</h3>
<p class="affilation">(1) Mott MacDonald, Sydney Australia
(2) Sydney Metro, Sydney, Australia & Centre for Audio, Acoustics and Vibration, University of Technology, Sydney, Australia</p>
<p><b>ABSTRACT</b><br>
The four largest capital cities in Australia are currently in the midst of constructing and commissioning what tend to be their biggest CBD public rail transportation infrastructure projects in a generation, to meet current and future demand. These projects all come with significant acoustic challenges, some of which are well planned for, and some which emerge during later stages of construction and commissioning. With a focus on the diverse and acoustically complex architecture associated with rail stations, the aim of this present paper is to examine how some of the challenges posed by fixed station facilities have been identified and practical solutions were developed by the various acoustic teams associated with testing and commissioning of these operational stations. The key aspects considered in this paper includes: Tunnel ventilation noise and vibration; Environmental noise emissions; Internal noise levels; Reverberation time; Intelligibility of Public Address systems; and The operation of Draught Relief Shafts and Platform Screen Doors.<br>
<br>
Finally, the paper provides an outline of some lessons learnt by the authors on some of the largest of these projects. These lessons will subsequently inform the design and setting of acoustic objectives for future Metro railway projects.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p61.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p30" class="affilation"></a>Considerations of External Noise and Vibration Factors in the Design of Sensitive Inpatient Facilities</h2>
<h3>Sheikh, Mahbub (1), Reboredo Gasalla, Pablo (1), Vega, Rodrigo (1)</h3>
<p class="affilation">(1) ACOR Consultants Pty Ltd</p>
<p><b>ABSTRACT</b><br>
To provide a better and wider range of healthcare services to the community, hospitals often require redevelopment, resulting in necessary expansion into an existing and quite often constrained building envelope. Due to limited space within the hospital compound, it is often the outcome that these expansions are constructed vertically, either above an existing clinical facility or above a mechanical plantroom. Additionally, the available spaces suitable for expansion may also conflict with existing helipads located on the rooftop. This presents noise and vibration isolation challenges in the design of sensitive inpatient facilities.<br>
<br>
Acoustic design of inpatient areas for hospitals requires careful consideration of transient or continuous noise and vibration factors that may be critical to patient diagnosis, comfort, and recovery. This paper explores the critical considerations of helicopter noise and mechanical plant vibrations in the design of inpatient areas within a hospital. These external factors pose challenges to patient comfort and recovery due to the vulnerable nature of the patient, necessitating effective design strategies to creating a calm and peaceful atmosphere conducive to patient healing and comfort.<br>
<br>
In this paper, we have assessed the helicopter noise, mechanical plant airborne and structure-borne noise in the design of an inpatient area, located above a mechanical plant room and adjacent to rooftop helipad. Helicopter operations including landing and take-off generate high-intensity noise levels, while mechanical plants contribute low-frequency noise and vibrations that are potential risk factors for the design and patient comfort. This paper reviews the current design guidelines and standards related to noise and vibration in healthcare facilities and discuss the architectural and engineering solutions including façade design and vibration isolation of structure as an effective mitigation measures of the challenging noise and vibration environment.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p30.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p99" class="affilation"></a>Developing geoacoustic seabed models for a shallow embayment with an elastic seafloor</h2>
<h3>Duncan, Alec D. (1), Tollefsen, Cristina (1), Parnum, Iain (1), Erbe, Christine (1)</h3>
<p class="affilation">(1) CMST, Curtin University</p>
<p><b>ABSTRACT</b><br>
The Western Australian Marine Science Institution (WAMSI) has carried out a multi-faceted study of Cockburn Sound, a shallow embayment south of Fremantle, prior to the establishment of a container port in the Sound. One aim of this study was to establish geoacoustic models of the seabed to facilitate numerical modelling of changes in underwater sound levels due to port construction and operation. The modelled sound levels will ultimately be used as part of an assessment of possible impacts of the new port on the marine animals that frequent the Cockburn Sound.<br>
<br>
In this paper we describe the overall geology of the Sound and the process used to establish appropriate geoacoustic seabed models, which included analysis of underwater recordings of ship noise and signals from a small airgun sound source. We will also discuss techniques for modelling acoustic propagation in this environment which are complicated by the presence of high shear-speed elastic seabed layers.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p99.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p53" class="affilation"></a>Bellhop Underwater Acoustic Simulation and Data Processing Optimisations: Getting Hi Def on the Desktop</h2>
<h3>Fang, Chung T C (1), Zander, Anthony C (1), Larizza, Francesco (2), Hassan, Eyad R (1), Robertson, William S P (1)</h3>
<p class="affilation">(1) The University of Adelaide
(2) Saab Australia Pty. Ltd.</p>
<p><b>ABSTRACT</b><br>
Bellhop is an established underwater acoustic raytracing model. Modern wrapper libraries have allowed integration with popular environments such as Python and it remains a relevant and useful tool. However, its practical performance can be limiting when trying to simulate scenarios to capture transient interactions between multiple sources in detail much greater than 10,000 nodes. In this study, we document the techniques we found useful in overcoming many of these limitations. <br>
<br>
The facility to simulates underwater sound propagation using Bellhop has been conveniently brought into the Python environment through wrapper libraries such as Arlpy, expediently interfacing with popular tools for machine learning and data analysis. Yet, for the most part, the libraries only act as data conduits to the core Bellhop legacy code. Developed in FORTRAN decades ago, this code base has not kept pace with evolution of the modern PC. Naive application of the Bellhop model strictly according to documentation severely underutilises modern hardware. Consequently, simulation detail and productivity experience avoidable limitations.<br>
<br>
Our particular interest was in simulating the combined sound field from many local emitters while also observing the effect in the far field. This required a dense resolution simulation over a wide expanse in area, time and frequency. The modelling requirements presented a series of challenges when starting from a straightforward direct application that extends beyond the raytracing task and include handling of large simulation data output. Specifically, producing a simulation for numerous sources using Bellhop quickly exhausted available memory and led to prohibitive processing time. These bounds to productivity and simulation detail can be pushed back by leveraging the potential of modern hardware through data parallelisation of large time series datasets to utilise multiple CPU cores and the use of vastly improved speeds in non-volatile solid-state storage to judiciously free up faster volatile memory while minimising the impact on performance.<br>
<br>
We built upon functionalities provided by Arlpy by tailoring algorithmic strategy and data flow pathways for modern hardware, achieving orders of magnitude performance gains in speed and model resolution. A case study will be presented with a PC composed of typical hardware (Intel i13900 CPU, 112GB DDR5 RAM, 4TB PCIe4 M.2 SSD), demonstrating a ten-fold speed-up and 20-times better memory efficiency over the initial naive implementation. This paper describes useful generalised methodologies we found in the Bellhop Python workflow so that they may benefit other projects.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p53.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p75" class="affilation"></a>Measuring the frequency characteristic of underwater sound recorders ST500 and ST600 from Ocean Instruments</h2>
<h3>Gavrilov, Alexander (1), Parnum, Iain (1), Sidenko, Evgeny (1), Tollefsen, Cristina (2)</h3>
<p class="affilation">(1) Curtin University
(2) Tollefsen</p>
<p><b>ABSTRACT</b><br>
The underwater sound recorders SoundTraps ST500 and ST600 from Ocean Instruments have been used for numerous underwater sound studies. The declared bandwidth of sound recording by both standard versions of SoundTraps is from 20 Hz to 60 kHz, and 20 Hz to 150 kHz for high-frequency model. Although calibration of the recorders' sensitivity to sound pressure is made for both recorder models at 250 Hz through utilising a Center 327 pistonphone, the frequency characteristic of recorders over the entire recording band is varying, especially at lower frequencies where the hydrophone capacitance and input impedance of the hydrophone preamplifier connected in series work as a high-pass filter with a roll-off of 6 dB per octave. To examine the frequency characteristics of both SoundTrap models and experimentally derive the sensitivity correction at low frequencies, measurements were carried out in a large pool using a water pump as a low-frequency source of underwater sound. Spectral levels of noise recorded by the SoundTraps were compared with those recorded by a fully calibrated hydrophone recording system. Results show that the sensitivity of ST500, ST 600STD and ST600HF have a significant roll-off at frequencies below approximately 30 Hz. Suggested corrections of the frequency characteristic for these three recorder models are proposed. Similar calibration measurements are planned to carry out for the ST202 and ST300 recorder models from Ocean Instruments.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p75.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p89" class="affilation"></a>Vibroacoustic response of a coated shell near a free sea surface</h2>
<h3>Sharma, Gyani Shankar (1), Lin, Cikai (2), Skvortsov, Alexei (1), MacGillivray, Ian (1), Kessissoglou, Nicole (2)</h3>
<p class="affilation">(1) Defence Science and Technology Group, Melbourne
(2) UNSW Sydney</p>
<p><b>ABSTRACT</b><br>
The vibroacoustic response of a coated cylindrical shell semi-immersed or fully submerged close to a free sea surface is studied. The coating comprises a soft material embedded with voids or hard inclusions. The analytical model accounts for local resonance of the inclusions, multiple scattering of waves between the inclusions, and strong fluid-structure interaction between the coated shell, the surrounding water, and the free sea surface. The influence of different coating designs and the free surface on the structural and acoustic responses of the semi- and fully immersed shells are presented. Results obtained analytically are compared with those obtained using the finite element method, showing excellent agreement.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p89.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p91" class="affilation"></a>Transition from perturbation to Kirchhoff approximation for modelling coherent reflection of underwater sound from rough sea surfaces</h2>
<h3>Zhang, Zhi Yong (1), Ayub, Md</h3>
<p class="affilation">(1) Defence Science and Technology Group, Edinburgh, SA 5111, Australia</p>
<p><b>ABSTRACT</b><br>
Wind roughens sea surfaces and generates waves. Wave-breaking produces air bubbles which can be transported downwards by Langmuir circulation currents. The interaction of underwater sound with sea surfaces involves several coupled mechanisms: (1) rough air-sea interfaces scatter incident sounds into coherent and incoherent components; (2) the sub-surface air bubbles absorb and scatter sound energy; and (3) the air-water mixed layer, with decreasing air/water volume ratio with depth, refracts sound energy upwards towards the surface. In this paper, we ignore the effect of bubbles and formulate a simple formula for the coherent components from scattering of the rough air-sea interfaces. The formulation is based on transitioning two well-known approximations for treating scattering from rough interfaces. The first one is perturbation approximation, which is suitable for small grazing angles. The second one is Kirchhoff approximation, which is suitable for large grazing angles. The new simple formula is suitable for all grazing angles and compares well with results from more complex numerical integration methods.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p91.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p97" class="affilation"></a>Novel prototype testing methods for vibration sensitive locations</h2>
<h3>Farrugia, Liam (1), Yates, David (1), Watson, Jonathan (2)</h3>
<p class="affilation">(1) WSP
(2) Mason Mercer</p>
<p><b>ABSTRACT</b><br>
As medical and scientific equipment grows more precise, so too does its need for vibration isolation. A specific project provided a case for providing vibration isolation to vibration impacts associated with a loading dock activity to sensitive laboratories located on upper floors. This paper presents testing results from prototype slab impact testing undertaken onsite to assess various methods of vibration isolation and their effects on vibration propagation throughout a structure. The testing focused on shock impact tests from the dropping of heavy masses onto the prototype slab. By utilising a prototype slab the response with different forms of mitigation could be measured and assessed to project specific criteria that adopted VC curves.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p97.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p118" class="affilation"></a>Experimental vibration analysis of a beam with ABH stiffeners</h2>
<h3>Martins, Daniel (1), Karimi, Mahmoud (2), Maxit, Laurent</h3>
<p class="affilation">(1) Centre for Audio, Acoustics and Vibration, University of Technology Sydney, Sydney, Australia
(2) INSA Lyon, LVA, UR677, 25 bis av. Jean Capelle, 69621 Villeurbanne Cedex, France</p>
<p><b>ABSTRACT</b><br>
In recent years, acoustic black holes (ABHs) have gained attention as a promising method for passive vibration control in engineering applications. This work experimentally investigates the use of ABHs in a stiffened beam to mitigate its vibrational response. The ABHs are embedded in the stiffeners rather than in the beam. Therefore, the structural integrity of the system is maintained. The study presents measured vibration responses of two stiffened beams excited by an impact force. The first case is a stiffened beam with traditional rectangular stiffeners, while the second case has ABH stiffeners. The ABH stiffeners are designed to match the surface area and moment of inertia of the rectangular stiffeners at the contact point with the beam, ensuring that both cases have similar weight and static stiffness. The experimental investigation explores three configurations: stiffeners without damping layers, with viscoelastic damping layers, and with constrained viscoelastic damping layers. The effect of these damping layers on the vibrational responses of both stiffened beams is examined. Results demonstrate the effectiveness of replacing traditional rectangular stiffeners with ABH stiffeners for vibration mitigation, highlighting the potential advantages of ABH technology in vibration reduction of stiffened structures.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p118.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p65" class="affilation"></a>Coupling of Circumferential Modes in a Circular Plate</h2>
<h3>Pan, Jie (1), Matthews, Dave (1), Ibrahim, Jacob (1)</h3>
<p class="affilation">(1) The University of Western Australia</p>
<p><b>ABSTRACT</b><br>
Unlike the vibrational modes of a circular plate with a perfectly clamped boundary condition, the characteristics of circular plates in practical scenarios are influenced by the clamping pressure at the boundary. In this paper, we explore how the natural frequencies of degenerated non-axial symmetric modes are shifted and split. These phenomena are explained by the coupling between circumferential modes, which is induced by non-uniform boundary conditions.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p65.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p14" class="affilation"></a>Footfall vibration on a high frequency walkway.</h2>
<h3>Duschlbauer, Dominik (1), Miller, Aaron (2), Spagnol, Joseph (1), Sirianni, Adam (1), McMcMahon, Jordan (1)</h3>
<p class="affilation">(1) SLR Consulting Australia
(2) Acoustic Studio</p>
<p><b>ABSTRACT</b><br>
The paper investigates the response of a light weight, high frequency timber-steel composite structure to footfall. Footfall vibration predictions methods for stiff floors are reviewed and measurement results of four different walkers using different stepping frequencies are discussed. The study focuses on the dependence of footfall vibration on stepping frequency.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p14.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p42" class="affilation"></a>Vibration Criterion Curves - Part 2: Application to Transients</h2>
<h3>Miller, Aaron</h3>
<p class="affilation">Acoustic Studio</p>
<p><b>ABSTRACT</b><br>
Part 1 of this paper explains the evolution of VC curves and summarises the most recent guidance. for medical and scientific research facilities containing sensitive equipment such as optical and electron microscopes that require a more stringent vibration criterion than human comfort thresholds, provided in the IEST's Recommended Practice (RP) 201.1. Part 2 focusses on the specific challenge of applying VC curves to transient events.<br>
<br>
The guidance summarised in Part 1 is clear about how 'steady-state' vibration should be assessed against VC curves but the question of how to quantify and assess the impact of transient vibration is particularly challenging and has not been fully resolved. In some cases, equipment suppliers and/or users can guide the assessment of transient vibration; however, in most cases, they cannot. <br>
<br>
This paper draws on recent guidance to address the questions frequently faced by practitioners when attempting to assess transient vibration against VC curves in the absence of guidance from equipment suppliers and/or users, such as integration times, how one-third octave band levels should be derived, time weightings and applicable locations. It recommends a benchmarking approach to determine the disruption tolerance of existing sensitive equipment and processes, using statistical techniques. Collating these benchmarks across a wide cross-section of facilities and equipment may allow for disruption tolerance thresholds to be determined in the future.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p42.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p41" class="affilation"></a>Vibration Criterion Curves - Part 1: Evolution and Interpretation</h2>
<h3>Miller, Aaron</h3>
<p class="affilation">Acoustic Studio</p>
<p><b>ABSTRACT</b><br>
The Vibration Criterion (VC) curves were first developed in the US in the early 1980s and are now widely used internationally, including in Australia, to assess and manage the impacts of vibration on sensitive medical and scientific equipment, such as optical and electron microscopes. Several iterations of the VC curves and associated guidance documents have since been published clarifying certain aspects of how the curves should be interpreted and applied. Australian policy and guidance documents refer to different iterations of the VC curves and the subtle differences between these iterations can create confusion regarding their application. This paper, the first of two parts, describes the evolution of the VC curves and aims to collate and summarise the most recent published guidance about how to interpret and apply the curves. A separate paper, part 2, discusses the ongoing challenge of how to apply the curves to transient vibration events.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p41.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p6" class="affilation"></a>Human-Induced Vibrations on Lightweight Footbridges</h2>
<h3>Reboredo Gasalla, Pablo</h3>
<p class="affilation">Member Australian Acoustic Society / Chartered Engineer Engineers Australia</p>
<p><b>ABSTRACT</b><br>
Footbridges are, by their nature, highly susceptible to human-induced vibrations as they may combine low levels of damping and low mass. Due to the increased flexibility and lightness of modern footbridges, dynamic forces can cause larger amplitudes, therefore, it is essential to pay greater attention to structural vibration and dynamic responses. The natural frequencies, damping properties, bridge mass and pedestrian loading, together, determine the dynamic response. The vibration behaviour caused by pedestrian traffic must be confirmed against the vibration monitoring and correlate with the design parameters.Then, it must be compared against the required human comfort standards and guidelines. If the vibration responses do not meet the comfort criteria, changes in the design or damping devices are advised.<br>
<br>
This paper presents the ambient modal testing and human-induced load tests for two in-service pedestrian bridges in Melbourne, Australia. The relevant modal parameters were extracted and the vibration serviceability limit state (VSLS) was assessed with the Eurocodes and the AS 5100, including relevant guidelines such as HIVOSS and SETRA.ISO 2631-1 and AS 2670-1 provides appropriate frequency weighting functions based on the vibration direction since the sensitivity of human body to vibration is frequency and direction dependent. Vibration predictors have been evaluated using both frequency weighted and unweighted functions and the results have been assessed against the use of these functions at dominant, relevant frequency responses of the footbridge.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p6.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p28" class="affilation"></a>The Victorian Environment Reference Standard and how it has been considered and applied in noise assessments</h2>
<h3>Buret, Marc (1), Just, Elaine (1), Mosley, Will (2)</h3>
<p class="affilation">(1) Air, Odour & Noise Sciences, Environment Protection Authority Victoria
(2) Climate Change, Water, Air & Noise Policy & Regulation, Environment Protection Authority Victoria</p>
<p><b>ABSTRACT</b><br>
The subordinate legislation made under the Victorian Environment Protection Act 2017 (the Act) includes an Environment Reference Standard (ERS) that was gazetted on 26 May 2021 and commenced, with the Act, on 1 July 2021. The ERS covers ambient air, ambient sound, land, as well as ground and surface water. Although it is not a compliance standard and does not take precedence over direct regulation, the ERS is an important tool to support the preventative approach to environment protection of the Act. It defines environmental values to consider when assessing the impacts on human health and the environment that may result from a proposal or activity, or from existing environmental conditions on a site. These values reflect desired outcomes for human health and the environment, such as (for ambient sound) sleep at night, child learning and development, normal domestic and recreational activities and enjoyment of natural areas. This paper presents a review of how the ERS has been considered when assessing the risks associated with noise.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p28.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p103" class="affilation"></a>Fairly assigning noise emission limits to new industrial precincts.</h2>
<h3>Jenkin, Lance (1), Fokkema, Carl (1)</h3>
<p class="affilation">(1) EMM Consulting Pty Limited</p>
<p><b>ABSTRACT</b><br>
New industrial or expansion of existing industrial precincts offer unique challenges to planners and developers. One of the challenges related to noise is how to fairly assign noise emission limits to sites in the precinct without knowing how the rest of the precinct will be developed. EMM Consulting Pty Limited has gained experience in preparing assessments for projects involving planning for future land use. This paper will describe three methods we have used for assessing industrial precincts. The first is a reverse modelling technique, where sources are placed on receivers around the precinct and noise contours are generated inside the precinct. The second method is to generate a risk map within the precinct using a grid of source points. The final method uses a developer's concept or master plan to determine noise allocation goals for the individual lots within the site.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p103.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p15" class="affilation"></a>A framework for drone noise management in an Australian context</h2>
<h3>McKay, Ryan S (1), Henrys, Nicholas (1), Jurevicius, Darren (1)</h3>
<p class="affilation">(1) Resonate Consultants</p>
<p><b>ABSTRACT</b><br>
With the number of unmanned aerial vehicle (UAV), or 'drone' flights in Australia expected to skyrocket, particularly in transport and logistics, managing their noise impacts is becoming increasingly critical. The mining industry currently accounts for a large portion of drone flights, but transport and logistics-related flights are forecast to reach 50 million annually by 2043, with forestry, agriculture, and environment expected to account for another 3.5 million flights. This rapid increase will create significant challenges, including managing the noise impacts which will increasingly reach cities, rural areas, and remote areas, instead of being more isolated in existing industrial areas. In this paper, we will discuss existing Australian regulations and propose a framework for assessing drone noise impacts within the Australian context. This framework involves using measured drone noise levels, flight operations, environmental data, propagation models, and assessment of cumulative impacts. There is a growing database of drone noise levels for flight, take-off, landing, and loiter. This can be combined with flight operations data, for example from a Flight Information Management System (FIMS), to predict noise emissions along a flight path. Noise propagation can be predicted using simple empirical models such as ISO 9613-2. The cumulative noise from multiple drone flights can then be calculated at sensitive receiver locations and assessed against noise management thresholds. Finally, we present a case study of delivery drones flying to random destinations with routes considering existing high background noise areas to discuss the impacts on people, including noise metrics and possible controls to minimise these impacts.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p15.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p104" class="affilation"></a>Noise assessment methodology for land-use planning</h2>
<h3>Teyhan, Katie (1), Carl, Fokkema (1)</h3>
<p class="affilation">(1) EMM Consulting Pty Limited</p>
<p><b>ABSTRACT</b><br>
EMM Consulting Pty Limited has gained significant experience in recent years preparing noise assessments for projects involving planning for future land-use. Assessing noise for future land-use typically involves the assessment of a large parcel of predominantly vacant land for future rezoning or development for industrial or commercial use. Our experience also involves preparation of noise impact assessments to accompany individual development applications as the industrial land release is progressively developed. Valuable insight has been gained into regulator's expectations, opportunities and constraints in relation to technical outcomes from a noise impact assessment as well as the limitations of current noise policy in NSW for this purpose. This paper will discuss our learnings from this experience. <br>
<br>
There are technical limitations to accurately predicting noise impacts when there is a high level of uncertainty about both the future proposed development and the surrounding acoustical environment. Consistency in the methodology of generating assumptions, specifically project specific noise levels, in this regard and development of a framework for assessment will provide increased certainty during the assessment and approval process. This will, in turn, lead to a more efficient development approval process and more equitable outcomes for all stakeholders. <br>
<br>
Improving the accuracy and relevance of project specific noise levels and noise modelling inputs will also enable relevant and practical outcomes for effectively managing noise from the site in the future. Noise modelling methods and technical assumptions that could be utilised to predict and manage likely impacts from industrial land releases are described. The importance of establishing clear expectations around technical outcomes and uncertainties is highlighted, to help all stakeholders understand the limitations of the noise study. The importance of collaboration and clear communication with all relevant stakeholders; proponents, regulators and communities, cannot be overstated. <br>
<br>
EMM has identified opportunities for improvement and clarification to the process outlined in the current noise policy, NSW Noise Policy for Industry (EPA, 2017), regarding the assessment of noise emissions from clusters of future developments. The necessity to consider how the surrounding acoustical environment will change as the subject site and surrounds are developed is emphasised. In some cases, it must be acknowledged that existing acoustical amenity cannot be preserved. Consideration of the broader context for the region and the current and future rezoning plans of local and State government is necessary.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p104.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p88" class="affilation"></a>Lessons in Education Building Design</h2>
<h3>Borgeaud, David</h3>
<p class="affilation">Acoustics Noise Vibration</p>
<p><b>ABSTRACT</b><br>
Education projects come in many shapes and sizes - from learning centres with general learning areas, to performing arts complexes with music, dance and drama studios, to indoor and outdoor sports facilities, kitchens and industrial technology and design buildings with full engineering workshops. Limited available land often requires use of multi-level, mixed use buildings, and location of facilities closer to residences. The level of acoustic input varies for each project and may include not just the room acoustics but also noise radiating to residential areas. This paper discusses the author's experience with several education projects.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p88.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p67" class="affilation"></a>A Parametric Study of Sound Leakage Through Openings and Fittings</h2>
<h3>Hayne, Michael (1), Devereux, Richard (2), Steel, Andrew (3)</h3>
<p class="affilation">(1) SoundBASE Consulting Engineers
(2) Acran Sound Control
(3) Ultrafonic</p>
<p><b>ABSTRACT</b><br>
How much does sound leakage due to openings and the installation of fittings in ceilings and walls impact upon overall sound reduction performance? In this paper, the results of a parameter study conducted in the Acran Sound Control Acoustic testing Laboratory are presented. The parametric study involved drilling holes in a sheet of 13mm plasterboard to investigate how the sound reduction and noise reduction performances changed as the hole size increased. Larger openings were then cut in the plasterboard to match common downlight sizes and the testing repeated with and without downlights installed to determine whether sound leakage through downlights is significant. Finally, a range of fittings such as power points and exhaust fans were tested to determine their influence on sound leakage.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p67.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p112" class="affilation"></a>Design and Verification of a High-Performance Acoustic Testing Laboratory</h2>
<h3>Lanchester, Michael Lewis (1), Edser, Carl Scott (1)</h3>
<p class="affilation">(1) Stantec Australia Pty Ltd</p>
<p><b>ABSTRACT</b><br>
This paper describes the design, construction, and performance verification of a new acoustic testing laboratory built to meet multiple international standards. The facility consists of source and receiver rooms with 150 m3 and 199 m3 volumes, separated by a 10.9 m2 test aperture. Key design features include non-parallel surfaces to optimize diffusion, vibration-isolated concrete floors, and high-mass walls to minimize flanking transmission.<br>
<br>
Extensive testing was conducted to verify compliance with AS 1191, ISO 10140-5, and ASTM E90 standards. Diffusivity was assessed using the absorption coefficient method, demonstrating convergence. Reverberation times exceeded 5 seconds across most frequencies, with absorption coefficients below 0.03, meeting AS 1191 criteria but requiring some problems to be solved to comply with other standards. Flanking transmission testing achieved a maximum measurable sound reduction of Rw 75 allowing testing of samples up to Rw 65, limited by equipment rather than facility performance.<br>
<br>
The results confirm the laboratory meets or exceeds all key standard requirements, enabling acoustic testing of materials and systems to all codes being considered. This paper details the critical design considerations, measurement techniques, and performance data for this NATA accredited acoustic testing facility.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p112.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p49" class="affilation"></a>A Comparative Assessment of Educational Acoustic Design Guidelines against NSW EFSG</h2>
<h3>Reverter Garcia, Jorge , Sepehrirahnama, Shahrokh, Milton, Joseph</h3>
<p><b>ABSTRACT</b><br>
This paper conducts a comparative assessment of the acoustic design considerations of the School Infrastructure New South Wales (SINSW) Educational Facilities Standard Guideline (EFSG) alongside nationally and internationally recognised guidelines for educational facilities. From the analysis, shortcomings stemming from an outdated guideline, as well as gaps in design clarity were identified. Areas lacking updates of best practices are highlighted and potential improvement for the mandatory EFSG acoustic criteria are recommended. Additionally, the acoustic design specifications were thoroughly examined from the viewpoint of ambiguity and potential overdesign, buildability and associated cost. The outcomes of this comparative assessment signify the importance of fostering a constructive dialogue between design team and stakeholders to establish an improved acoustic guideline that will create innovative and sustainable acoustic environments that considers user's needs and enhance the functionality of educational spaces.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p49.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p115" class="affilation"></a>A practical modification to ISO 8297:1994 for unattended sound power level measurement of land drilling rigs.</h2>
<h3>Dever, Matthew (1), Joshua, Dyer (1), Yeldham, Andrew</h3>
<p class="affilation">(1) MAAS</p>
<p><b>ABSTRACT</b><br>
Land drilling rigs are large, mobile machines operating continuously in Australia's gas fields. These rigs must comply with noise limits, some of which are determined by the calculated sound power level according to ISO 8297:1994 Acoustics - Determination of sound power levels of multisource industrial plants for evaluation of sound pressure levels in the environment - Engineering method. The standard involves surrounding a defined plant area with an array of microphones, and typically requires an attended measurement session. However, attended surveys at operational drilling rigs are impractical for various reasons, leading to a preference for unattended noise surveys. Furthermore, physical limitations often prevent placing microphones beyond the well pad perimeter, making strict adherence to ISO 8297:1994 unreliable due to mobile noise sources (such as front-end loaders and trucks) operating too close to the microphones. To address these challenges, a modification to the ISO 8297:1994 calculation procedure has been investigated. The goal is to provide accurate sound power level results even when noise sources approach closer to the microphones than the standard allows.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p115.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p72" class="affilation"></a>Detection of aircraft noise with a buried fibre-optic array</h2>
<h3>Gurevich, Boris (1), Tertyshnikov, Konstantin (1), Isaenkov, Roman (1), Vorobev, Mikhail (1), Pevzner, Roman (1)</h3>
<p class="affilation">(1) Curtin University</p>
<p><b>ABSTRACT</b><br>
Distributed acoustic sensors (DAS) can detect and monitor various sources of seismic energy, both natural (proximate, regional and remote earthquakes; ocean storms) and anthropogenic (mine blasts, vehicle and pedestrian traffic). An intriguing question is whether buried DAS cables loosely coupled to the ground can detect aircraft noise generated in the air. Such detection may be useful for independent monitoring of air traffic by leveraging vast existing fiber-optic telecommunication networks. Previous studies show that spectrograms of aircraft noise recorded by geophones contain a narrow-band signal whose frequency decreases with time as the aircraft is passing in the vicinity of the receiver. This distinct frequency shift is associated with the doppler effect, as the intrinsic frequency emitted by the aircraft (80-100 Hz) is shifted in proportion to its apparent speed with respect to the position of the receiver. Yet recording such noise using a buried DAS array may be challenging as most of the atmospheric sound is likely to be reflected by the earth surface. To explore the possibility of detecting aircraft noise, we recorded DAS data over four weeks using a telecommunication fiber-optic array buried beneath the Curtin University campus, about 10 km from Perth International Airport. The DAS gauge length was 10 m.<br>
<br>
Inspection of DAS spectrograms corresponding to passing aircraft showed that some of them do show this distinct Doppler pattern <br>
<br>
However, this pattern was only observed for some aircraft. A detailed case by case analysis in conjunction with radar data shows that these signals are limited to turboprop airplanes. The noise from jet aircraft has a higher frequency, which cannot be detected with a DAS gauge length of 10 m. Indeed, we have managed to detect jet aircraft using a smaller gauge length, but those data require further investigation. <br>
<br>
The variation of the central frequency with time was used to estimate the intrinsic frequency of the aircraft (83 Hz), the shortest distance between the aircraft and sensor (600 m) and the aircraft ground speed (365 km/h). This speed co-insides with that given by FlightRadar24 at that point. <br>
<br>
The authors acknowledge the financial support from the Australian Department of Industry, Science and Resources for the 2021 Global Innovation Linkage (GILIII000114) grant funding and the sponsors of the Curtin Reservoir Geophysics Consortium. The authors thank Gang Fang of Shandong University and Yunyue Elita Li of Purdue University for useful discussions.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p72.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p66" class="affilation"></a>Variation in acoustic radiation of a fluid-loaded cantilever excited by point or distributed force</h2>
<h3>Howell, Richard (1), Waldman, W (2), Tsigklifis, K (1), Cao, Huong (3), Dylejko, Paul (1), Williams, Paul (3), Karimi, Mahmoud (3)</h3>
<p class="affilation">(1) DSTG Melbourne
(2) DSTG Melbourne, YTeK
(3) UTS</p>
<p><b>ABSTRACT</b><br>
The acoustic radiation of vibrating fluid-loaded cantilevers is a canonical problem that has many applications in industry e.g. the noise generation of wind-turbine blades. The focus of this study is the extent to which our reduced-order model (Tsigklifis et al., AAS 2021) can capture the underlying physics of this problem that includes the effect of material flexibility on sound generation. An additional benefit is that models of this type are computationally efficient compared to commercial software. Benchmark results for comparison of a fluid-loaded (stationary flow) cantilever are produced using COMSOL. Cantilevers of both uniform and aerofoil cross-section have been excited by point and distributed forces at different locations on the cantilever for frequencies up to 60 kHz generating values of drive-point mobility and acoustic radiation. Of principal interest is the effect of varying the location of the excitation force on the cantilever between the mid-chord and the trailing edge. Our reduced-order model couples a 1D Euler-Bernoulli beam in translation and rotation with Theodorsen's unsteady aerofoil model capturing the added mass and the Rayleigh integral equation for the acoustic radiation. The effect of chordwise modes along the cantilever cannot be modelled using this technique. Their effect is investigated by extending another of our 1D models (Howell et al., AAS 2023) to two dimensions by coupling a 2D finite-difference model of a thin plate with a 2D panel method that imposes the static fluid loading of an ideal fluid. No acoustics are captured by the 2D model and so it is only used for comparison with predictions of drive-point mobility. Initial results show that the dominant features of the COMSOL predictions are well captured by the 1D model for the first three modes of vibration. The 2D model more accurately captures certain features of the high frequency response.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p66.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p54" class="affilation"></a>Denoising by neural network for muzzle blast detection</h2>
<h3>Pujol, Hadrien (1), Bevillacqua, Matteo (1), Thirard, Christophe (1), Mazoyer, Thierry (1)</h3>
<p class="affilation">(1) Acoem</p>
<p><b>ABSTRACT</b><br>
Acoem develops gunshot detection systems, consisting of a microphone array and software that detects and locates shooters on the battlefield.<br>
<br>
The performance of such systems is obviously affected by the acoustic environment in which they are operating: in particular, when mounted on a moving military vehicle, the presence of noise reduces the detection performance of the software. To limit the influence of the acoustic environment, a neural network has been developed. Instead of using a heavy convolutional neural network, a lightweight neural network architecture was chosen to limit the computational resources required to embed the algorithm on as many hardware platforms as possible.<br>
<br>
Thanks to the combination of a two hidden layer perceptron and appropriate signal processing techniques, the detection rate of impulsive muzzle blast waveforms (the wave coming from the detonation and indicating the position of the shooter) is significantly increased. With a rms value of noise of the same order as the muzzle blast peak amplitude, the detect rate is more than doubled with this denoising processing.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p54.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p100" class="affilation"></a>Evidence-Based Interventions for Auditory Processing Issues in Individuals Who are Neurodiverse</h2>
<h3>Schafer, Erin (1), Mathews, Lauren (1), Gopal, Kamakshi (1), Miller, Sharon (1), Lam, Boji (1)</h3>
<p class="affilation">(1) University of North Texas</p>
<p><b>ABSTRACT</b><br>
Many children and young adults diagnosed with autism spectrum disorder (ASD) experience substantial auditory processing issues despite the presence of normal, pure-tone hearing sensitivity. Relative to neurotypical peers, individuals with ASD report and experience poorer auditory filtering abilities, binaural integration (dichotic listening), speech recognition in noise, temporal processing, and spatial processing. This presentation will begin with a review of auditory issues in this population and will be followed by a summary of four strategies and evidence-based interventions to mitigate auditory issues found in most individuals who have ASD. These strategies include (1) the use of remote-microphone hearing technology, (2) computerized dichotic auditory training, (3) one-on-one speech-in-noise training, and (4) university social and peer support groups.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p100.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p76" class="affilation"></a>The effect of white noise and "coloured" noise on cognition and sleep</h2>
<h3>Wilson, Wayne</h3>
<p class="affilation">The University of Queensland</p>
<p><b>ABSTRACT</b><br>
The past decade has seen an increasing number of reports in the scientific community of auditory white noise (WN) benefiting rather than hindering cognition and/or sleep in some adults and children. These reports have been enthusiastically extended by reports in the non-scientific community of different "coloured" noises benefitting different aspects of cognition and/or sleep. This paper reviews the scientific literature to find equivocal evidence for WN facilitating some cognitive processes, little-to-no evidence for WN benefitting sleep, and no evidence for different "coloured" noises benefitting different aspects of cognition or sleep. These findings suggest any effects of noise on cognition and/or sleep are likely to depend on complex interactions between noise type and cognitive and/or sleep processes in a manner that varies across different adult and child populations.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p76.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p37" class="affilation"></a>Preventing sleep disturbance using a qualitative approach</h2>
<h3>Konchery, Abhinav (1), Sacharz, Joanna (2), Buret, Marc (1), Just, Elaine (1)</h3>
<p class="affilation">(1) Air, Odour & Noise Sciences, Environment Protection Authority Victoria
(2) Data Analytics & Intelligence</p>
<p><b>ABSTRACT</b><br>
Noise is a significant cause of sleep disturbance, and affects the overall sleep quality, which can result in physiological effects including cardiometabolic, endocrine, cognitive, and psychiatric impacts. While environmental noise, particularly from road traffic is a common cause of sleep disturbance, other sources of noise such as nearby industries or neighbouring leisure activities can also have similar effects. Recommendations in health guidelines are typically expressed using metrics such as Lnight, LAeq,T and Lden, including when sleep is the considered health outcome. However, these metrics represent an average noise exposure over the measurement period and are limited in representing the risk of sleep disturbance associated with transient noise or sporadic loud events. In this context, it is relevant to qualitatively consider the risks to the environmental value of sleep, as opposed to solely relying on criteria and metrics. This paper discusses how a person/facility (duty holders) responsible for noise emissions or anyone generating noise could consider qualitatively, the value of sleep and implement preventative measures that are not necessarily reliant on quantitative metrics.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p37.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p45" class="affilation"></a>Considerations and strategies for cumulative industrial noise management using the NSW Noise Policy for Industry (NPfI)</h2>
<h3>Leslie, Angus (1), Phillips, Rodney (1)</h3>
<p class="affilation">(1) Renzo Tonin & Associates</p>
<p><b>ABSTRACT</b><br>
The NSW Noise Policy for Industry (NPfI) sets out the NSW Environment Protection Authority's (EPA's) requirements for the assessment and management of noise from industry in NSW. It includes guidance on the management of cumulative industrial noise from multiple industrial developments, which can vary depending upon if there is a single controlling entity (eg. port area) or they operate independently (eg. employment lands). Recent experiences have identified several issues that arise with the implementation of this guidance when managing cumulative noise from multiple industrial facilities during the assessment process. Experience has also shown that there are additional considerations that should be included to determine a suitable approach to maximise the potential operations from all industrial lots and minimise noise allowances from being unnecessarily complicated or overly restrictive. This paper identifies several issues with the current way cumulative industrial noise management is being implemented across the planning, development, construction, and operational stages and provides additional strategies that can be considered to achieve the intended outcomes of the NSW NPfI.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p45.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p74" class="affilation"></a>Assessing Noise Amenity Within the Context of an Occupational Noise Assessment</h2>
<h3>Mrost, Mischa J.</h3>
<p><b>ABSTRACT</b><br>
With increasing demand for fibre capacity and ongoing technological developments, modern telecommunications (comms) equipment is generally operating with higher capacities in much smaller units. Cooling fan sizes within these units have become smaller and operate at higher speeds. A state-wide roll-out of new comms equipment in comms rooms across Queensland, resulted in numerous and on-going complaints from technicians over the increased noise levels and tonality this equipment produced. While the comms room noise levels complied with workplace health and safety noise exposure limits, a detailed noise investigation was initiated to assess noise amenity. This paper provides an overview of the assessment approach and results, including a broader discussion on improving noise amenity within the context of an occupational noise assessment, which is not currently within the scope of legislative requirements.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p74.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p35" class="affilation"></a>The Sonic Gathering Place Installation, Melbourne: User Experience and Post-Hoc Assessment of Sound Levels</h2>
<h3>Brown, Lex A.L. (1), Lacey, Jordan (2), Neudorfl, Tom (3)</h3>
<p class="affilation">(1) Griffith University
(2) RMIT University
(3) Metro Dynamics</p>
<p><b>ABSTRACT</b><br>
The Sonic Gathering Place (SGP) - designed in a research project by the second author - is an urban furniture installation constructed in an RMIT University courtyard. It consists of a 6.5m diameter annular seating arrangement with planter boxes. Speakers in the SGP reproduce natural sounds recorded in four national parks where the plants are native species. The design of the SGP, the field recordings in the national parks, and the sound reproduction system, are described elsewhere. This paper focuses on two aspects of the SGP, as installed. Firstly, it reports user's enjoyment of the SGP and their opinions regarding the effectiveness of this biophilic sound design in: encouraging them to stop and listen; providing the restorative effects experienced in nature; and by confirming their accord that the sounds, recorded in nature, complemented the plantings. Some methodological triangulation of these results is provided by the length of time users chose to spend at the SGP (median and modal durations of visits were 10 to 15 minutes) and their reports of being engaged, while there, in passive or reflexive pursuits. Secondly, this paper reports the levels of the background sounds at the installation site, and the levels that users would experience at the SGP during playback of the introduced sounds. This was a post-hoc examination of levels, as measurement had no role in the designer's determination of the playback levels of the natural sounds. Playback levels had been set through trial-and-error during SGP installation to achieve the designer's biophilic design intentions. The introduced sound levels proved to be only marginally louder than sound levels that existed before the installation. This information may provide useful guidance for further installations that include sound in their design and aid in the selection of sites where sound designs may prove attractive to users.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p35.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p117" class="affilation"></a>Modeling Low-Frequency Sound Propagation in a Ducted Atmosphere Using a Semi-Analytic Finite Element Method</h2>
<h3>Castro Mota, Rafael (1), Kirby, Ray (2), Williams, Paul (3), Jacob, Stefan (1)</h3>
<p class="affilation">(1) Physikalisch-Technische Bundesanstalt - Braunschweig/ TU Braunschweig
(2) RMIT University
(3) University of Technology Sydney</p>
<p><b>ABSTRACT</b><br>
Winds and temperature inversions can cause acoustic refraction, enabling the efficient propagation of low-frequency sound over long distances within acoustic waveguides. In this study, the semi-analytic finite element (SAFE) method is employed to predict this effect in stratified, inhomogeneous, moving air for range-independent noise propagation over reflective half-planes. We present a solution for a point source radiating in an atmosphere with a power-law wind profile. The results are compared to direct numerical solutions of the two-dimensional linearized Euler equations. Additionally, we examine the numerical convergence of the computed acoustic modes and demonstrate how to select modes associated with acoustic ducting near the ground. For large, range-independent domains, the proposed procedure proves to be much more efficient than the tested direct numerical computations. Thus, the method offers a viable approach for benchmarking other pressure field prediction techniques.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p117.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p29" class="affilation"></a>Report review for consulting acousticians</h2>
<h3>Ottley, Matthew (1), Wilkening, Siiri (1)</h3>
<p class="affilation">(1) Marshall Day Acoustics</p>
<p><b>ABSTRACT</b><br>
Having calculations and documents reviewed is an important aspect of practicing as an acoustic consultant, through all stages a consulting career. There is often relatively little training, instruction and guidance on the review process provided to consultants. This can manifest as trepidation or concern from reviewees or as unhelpful or unfocused output from reviewers. This paper addresses the three most common types of review encountered in consulting, being internal review, external review and peer review. Guidance is provided on the main areas which each type of review should focus on. For each type of review examples of common pitfalls are also provided. The paper is intended to provide guidance to both reviewers and reviewees.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p29.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p113" class="affilation"></a>Temperature Inversion Frequency From Sigma-Theta</h2>
<h3>Todoroski, Aleks (1), Kjellberg, Dan (1), Wassermann, John (2), Hall, Nic (3), Whitting, Rohan (1)</h3>
<p class="affilation">(1) Todoroski Air Sciences
(2) UTS Industry/Professional Fellow
(3) SoundIN</p>
<p><b>ABSTRACT</b><br>
The NSW Environment Protection Authority in their Noise Policy for Industry (NPfI) requires the consideration of certain meteorological conditions that may increase noise levels by focusing sound wave propagation paths at a single point. Such refraction of sound waves will occur during temperature inversion conditions. <br>
<br>
One of the principal methods recommended in the NPfI to identify the strength of a temperature gradient is to use a relationship developed by the US Atomic Energy Commission between temperature gradient and atmospheric stability categories. To determine atmospheric stability categories typically requires the measurement of sigma-theta (the standard deviation of wind direction), wind speed and time of day.<br>
<br>
This paper reviews how sigma-theta is often analysed to estimate atmospheric stability category for acoustic purposes.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p113.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p16" class="affilation"></a>Noise Management Strategies: Large-Scale Solar BESS Projects in Australia</h2>
<h3>Ayva, Burak (1), Wong, Samuel (1), Weyers, Beau (1)</h3>
<p class="affilation">(1) Noise and Vibration Division, Trinity Consultants Australia, Queensland, Australia</p>
<p><b>ABSTRACT</b><br>
Abstract - The industrial deployment of Battery Energy Storage Systems (BESS) is rapidly increasing in Australia, driven by advancements in cost-effective energy storage technologies. In Australia, significant investments are being made in BESS projects across Australia, aiming to leverage their numerous benefits, including peak load management, grid stability, renewable energy integration, and market participation. <br>
<br>
However, the proliferation of BESS projects, often situated in rural areas, presents considerable noise management challenges. This paper explores the noise issues associated with large-scale solar BESS projects and discusses effective mitigation strategies based on experiences from key projects in QLD, NSW, and VIC. Challenges identified include obtaining accurate noise data on new technology, directivity of noise, and the practicalities of implementing extensive and often tall noise barriers. Effective strategies beyond traditional barriers include the reorientation of BESS units, reorganising BESS station layouts, use of acoustic enclosures and louvres, adjusting cooling fan speeds, and engaging with manufacturers for acoustic optimizations. Proactive risk management through early engagement of noise engineers in the project lifecycle is emphasized to ensure compliance with strict Australian environmental noise regulations and to reduce cost during design phase. This study reviews effective strategies, beyond traditional barriers, and underscores the importance of strategic planning and innovative noise mitigation to facilitate the sustainable growth of BESS projects in Australia.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p16.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p98" class="affilation"></a>Design and implementation of a masking system for tonal industrial noise emissions</h2>
<h3>Beresford, Tim (1), Cyril, Max (1)</h3>
<p class="affilation">(1) NDY</p>
<p><b>ABSTRACT</b><br>
A noise source that exhibits tonal qualities is often deemed to be more annoying than one which is broadband in nature. As such, in environmental noise assessments, it is common to apply a decibel penalty (typically up to +5dB) to noise sources with tonality. Tonality is often objectively classified as a function of the spectrum shape described in narrow bands, where a prominent band relative to its adjacent bands indicates tonality. This paper outlines the practical implementation of a tonality masking system which was applied to a low-frequency industrial noise compliance issue. The system intended to remove the tonality penalty by introducing masking noise, altering the spectrum shape favourably. The added masking needed to be targeted to not only remove the tonality classification, but also minimise the increase in overall A-weighted level to less than one decibel. A feed-forward Unity software system was developed which accurately detected the tones in real-time and calculated the optimum masking signal in third octaves. The signal was then reproduced through a subwoofer within the industrial facility. After commissioning, the resultant noise levels were assessed and found to be non-tonal, with an overall A-weighted level increase of no more than 0.8dB. This case study was in Western Australia which has a legislated definition for tonality, although other local authorities have similar definitions for tonality, meaning the masking system developed here could have much broader tonality masking applications across Australia (and internationally).</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p98.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p27" class="affilation"></a>Mitigating Rubbish Truck Noise - A Case Study</h2>
<h3>Law, Harvey (1), Hayne, Michael (2), Kierzkowski, Marek (1)</h3>
<p class="affilation">(1) MEGASORBER PTY LTD
(2) SoundBASE Consulting Engineers Pty Ltd</p>
<p><b>ABSTRACT</b><br>
This paper explores the challenges of mitigating noise produced by rubbish trucks, particularly the sharp sounds generated when recyclable glass bottles fall from collection bins into trucks. During this process, maximum noise levels reach 118 dB(A), significantly higher than the truck's operational noise level of approximately 85 dB(A). The objective was to reduce the noise levels as much as possible, ideally aligning them with Environmental Protection Agency (EPA) guidelines. The study considered two types of rubbish trucks - Side Loaders and Rear Loaders - both of which are highly weight-sensitive. Since redesigning the trucks was not feasible, the noise mitigation measures needed to be suitable for retrofitting existing vehicles. To achieve this, repeatable testing methods were developed to simulate the noise produced by falling glass bottles. Noise levels were measured before and after implementing noise reduction treatments. This paper presents the results of these treatments and offers further recommendations for minimising noise levels in similar situations.This paper explores the challenges of mitigating noise produced by rubbish trucks, particularly the sharp sounds generated when recyclable glass bottles fall from collection bins into trucks. During this process, maximum noise levels reach 118 dB(A), significantly higher than the truck's operational noise level of approximately 85 dB(A). The objective was to reduce the noise levels as much as possible, ideally aligning them with Environmental Protection Agency (EPA) guidelines. The study considered two types of rubbish trucks - Side Loaders and Rear Loaders - both of which are highly weight-sensitive. Since redesigning the trucks was not feasible, the noise mitigation measures needed to be suitable for retrofitting existing vehicles. To achieve this, repeatable testing methods were developed to simulate the noise produced by falling glass bottles. Noise levels were measured before and after implementing noise reduction treatments. This paper presents the results of these treatments and offers further recommendations for minimising noise levels in similar situations.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p27.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p25" class="affilation"></a>Effectiveness of acoustic lagging pipes in outdoor environments</h2>
<h3>Macabenta, Neil</h3>
<p class="affilation">Northrop Consulting Engineers</p>
<p><b>ABSTRACT</b><br>
Mitigation measures to control pipe or duct breakout noise can be limited, especially when access to the pipe for servicing or maintenance is a primary requirement. Pipe lagging is a cost effective mitigation measure to control pipe breakout noise but is rarely used in outdoor applications. This paper provides a case study where acoustic lagging was applied in an outdoor environment. As part of the study, measurements were taken before and after the acoustic lagging was applied to determine the in-situ performance of the acoustic lagging. The findings indicate that specific types of acoustic lagging can significantly reduce noise break out from pipes. Further research could explore optimising lagging materials and techniques to further reduce noise break out.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p25.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p122" class="affilation"></a>Beyond the Decibel - Managing Noise from Outdoor Concert Venues</h2>
<h3>Marchuk, Alex (1), Henry, Frank (1)</h3>
<p class="affilation">(1) Brisbane City Council</p>
<p><b>ABSTRACT</b><br>
There is more to managing the community noise impacts of large outdoor concerts and festivals than simply setting a noise limit. An analysis of the data associated with outdoor concerts in Brisbane has identified that the risk of noise complaints is influenced by many factors other than the noise limits for the concert. The scheduling of events, frequency of events, event location, event duration, music genre and community engagement and attitudes can be more significant than the noise limits alone. This paper will explore all these factors and how understanding their influence on the community can enable noise regulators to go beyond the decibel to minimise the risk of noise complaints from large outdoor concerts and festivals.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p122.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p13" class="affilation"></a>Entertainment Sound and Noise Controls for the amended City of Sydney DCP</h2>
<h3>Parry-Jones, Joel (1), Leembruggen, Glenn (2)</h3>
<p class="affilation">(1) PKA Acoustic Consulting
(2) Acoustic Directions</p>
<p><b>ABSTRACT</b><br>
The City of Sydney Council is amending the Sydney Development Control Plan 2012 (DCP) to provide entertainment sound management control for new venues and new sensitive receivers.<br>
<br>
Acoustic Directions and PKA Acoustic Consulting were commissioned to advise on a suitable entertainment sound criteria that can balance promoting nightlife while ensuring residential amenity.<br>
<br>
This involved setting both an intrusive and amenity noise criteria, while considering existing legislation such as the Liquor and Gaming noise condition.<br>
<br>
The research and advice also involved guidance on how new venues can consider noise breakout in the design stage, and practical ways the Council can assess appropriate submissions.<br>
<br>
For new residential developments, guidance on sound attenuation options for facades while maintaining natural ventilation was developed. This was informed from previous joint research with the Council.<br>
<br>
The amended DCP will be publicly exhibited in July 2024 with the desire to be legislated before the Acoustics 2024 conference.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p13.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p12" class="affilation"></a>Outdoor Event Noise Monitoring - Lessons Learnt and Recommendations for Future Events</h2>
<h3>Weyers, Beau (1), Wong, Samuel (1), Ayva, Burak (2), Mazur, Witold (1)</h3>
<p class="affilation">(1) Noise and Vibration Division, Trinity Consultants Australia, Queensland, Australia
(2) Civil Engineering Department, Istanbul Technical University, Istanbul, Turkiye</p>
<p><b>ABSTRACT</b><br>
Outdoor concert and festival music events generally operate under the local legislative requirements, while touring artists are only interested in achieving their desired 100 dBA at front of house operating levels. This paper reviews 13 years of experience and more than 200 outdoor concert events and festivals, in the capacity of noise monitoring and live management, and discusses the insights gained regarding the interpretation of noise criteria and ability to achieve practical outcomes. <br>
<br>
In review of the various venues, limits, parameters and interested parties expectations, one recurring factor stands out: the inconsistency of noise criteria parameters across different jurisdictions in Australia. This variability complicates the efforts of event operators to meet regulatory requirements, often leading to confusion, frustration and non-compliance. The paper discusses the variety of adopted parameters utilised for noise limits, which are generally set on behalf of affected sensitive receivers. By reviewing these issues against the wealth of event experience, this paper aims to contribute to more effective and efficient noise management practices in the event industry, aiming for regulatory adherence, operator comprehension, and the minimization of unreasonable noise pollution impacts, with an overarching focus on how the Acoustician operates under the various expectations.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p12.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p102" class="affilation"></a>Technical considerations in evaluating environmental noise from entertainment venues</h2>
<h3>Zoontjens, Luke</h3>
<p class="affilation">SLR Consulting Australia</p>
<p><b>ABSTRACT</b><br>
As our cities continue to develop more densely populated urban areas, amplified music from entertainment venues are considered in the context of residential amenity. Amplified music may be considered important to vibrancy and economic activity, but it is also a source of potential complaint to nearby residents. To provide certainty to stakeholders, some authorities have implemented planning and regulatory controls around environmental sound from entertainment venues and/or adjacent development. These controls define criteria and assessment methods in order to determine the acceptability of various proposals.<br>
<br>
The challenge with these criteria and assessment methods are that they rely on various assumptions around measurement and prediction. Of particular interest to this study are issues which relate to low frequency sound and vibration effects. In this paper, we review some of the physical limitations and errors that can be expected, and provide recommendations for improvement.<br>
<br>
To reduce reliance on specialist expertise and increase the consistency of entertainment noise assessments, increased industry education and more specific methods of measurement and prediction are recommended.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p102.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p106" class="affilation"></a>Balancing Speech Privacy and Embodied Carbon Reduction in Building Design</h2>
<h3>Alamshah, Vahid (1), O'Conner, Colin (2), Bodsworth, Neil (3)</h3>
<p class="affilation">(1) Principal Engineer, Cundall
(2) Associate, Cundall
(3) Principal Consultant, Cundall</p>
<p><b>ABSTRACT</b><br>
Appropriate speech privacy between two spaces depends not only on partition sound insulation but also on background noise levels within the receiving room. While high sound insulation requirements can escalate construction costs and increase the embodied carbon footprint of acoustic designs, sound masking may provide a unique solution. By elevating background noise, sound masking achieves comparable acoustic privacy while reducing the need for high-insulation materials. Beyond carbon reduction, sound masking can also present advantages in achieving a more robust speech privacy outcome. This paper explores the benefits of sound masking as a possible tool in enabling a low carbon design as well as its potential for more robust speech privacy outcome.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p106.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p85" class="affilation"></a>Acoustic Design for Queensland Ballet's Thomas Dixon Centre Refurbishment</h2>
<h3>Heddle, James</h3>
<p class="affilation">-</p>
<p><b>ABSTRACT</b><br>
In a near decade long process, the state heritage listed home of the Queensland Ballet, the Thomas Dixon Centre has been redesigned and undergone extensive refurbishment and extension works to transform into a world-class facility and new cultural hub for Brisbane.<br>
<br>
The refurbished home now accommodates new dance studios, a performance space and wellness centre, expanded wardrobe and production facilities together with function spaces and café.<br>
<br>
This paper presents acoustic design aspects of the project, the problems to be solved and solutions used to deliver a successful outcome for Queensland Ballet and the design team.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p85.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p77" class="affilation"></a>Predicting impulsive noise emission and compliance with AAAC gymnasium guideline criteria</h2>
<h3>McCafferty, Sara (1), Byrick, Wilson</h3>
<p class="affilation">(1) Pliteq</p>
<p><b>ABSTRACT</b><br>
A prediction method has been developed to incorporate the AAAC Guideline for Acoustic Assessment of Gymnasiums and Exercise Facilities into gym flooring design. The impulsive noise emission is predicted using laboratory drop tower data and an in-situ standard drop on a calibrated reference sheet. This prediction method greatly reduces the time spent field testing and allows the prediction of LAFmax(ΣOct,31.5-250Hz) at various drop weights and heights on different flooring buildups. This paper provides an overview of the prediction model methodology and presents two case studies based on field measurements. The first case study predicts LAFmax(ΣOct,31.5-250Hz) midspan versus beside a column and compares the levels for three flooring types. The second case study analyses the change in predicted LAFmax(ΣOct,31.5-250Hz) with increasing distance from the receiver. For both cases, the prediction method is compared with results from the simplified SEA method described by the ANC and IOA in the Gym Acoustics Guidance (GAG).</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p77.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p82" class="affilation"></a>Comparative testing of Acoustic Isolation Properties of Mixed Cell Polyurethane (PUR) Elastomer in Lightweight Floating Floors</h2>
<h3>Rizal, Arinah, Pearce, Hilary, Ding, Kaiyi</h3>
<p><b>ABSTRACT</b><br>
This paper examines the material properties of mixed cell polyurethane (PUR) elastomer as an acoustic isolator. This isolator achieves good acoustic isolation while requiring minimal floor cavity depth (whereas conventional isolators such as steel springs or rubber mounts typically deliver only one or the other). This paper presents comparative testing of cube shaped PUR isolators, damped springs and rubber mounts as part of a lightweight floating floor over a concrete slab. Field measurements of impact sound and vibration transmission through these floor systems were conducted using multiple methods, which include dropping heavy-hard impact objects of different mass and shape. The results show that floating floor systems with PUR isolators perform similarly to damped springs in terms of noise and vibration isolation. The material characteristics of PUR isolators are also examined, particularly those which make them cost-effective and suitable for conventional applications in lightweight floating floors.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p82.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p40" class="affilation"></a>Vibration of a cantilever panel due to turbulence ingestion, part II: A virtual experiment</h2>
<h3>Kha, Jamie (1), Karimi, Mahmoud (1), Cao, Huong (1), Dylejko, Paul (2)</h3>
<p class="affilation">(1) Centre for Audio, Acoustics and Vibration, University of Technology Sydney, Sydney, Australia
(2) Platforms Division, Defence Science and Technology Group, Melbourne, Australia</p>
<p><b>ABSTRACT</b><br>
In the first part of this investigation, a semi-analytical approach was presented to predict the vibration response of a cantilever panel due to turbulence ingestion. This study focuses on the practical implementation of numerical experiments using a virtual synthesis of the source scanning technique. This practical framework will serve as a prototype for laboratory investigations. To practically predict the vibration response of a cantilever plate due to turbulence interaction at the leading edge, the problem can be re-framed as synthesising the corresponding response of a structure with an existing pressure field. An array of acoustic compact sources, such as monopoles, can sufficiently excite a structure creating the existing acoustic pressure field. This acoustic pressure field can instead be replicated using the superposition principle, whereby a synthetic array of a single monopole scanning over the structure can replace the array of monopoles. Complex amplitudes are derived from fitting the existing acoustic pressure field to a target pressure field and are subsequently used to scale measured frequency response functions due to the source scanning monopole sources to synthesize the predicted vibration response. It is anticipated that this framework will complement wind tunnel testing as an efficient estimation.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p40.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p39" class="affilation"></a>Vibration of a cantilever panel due to turbulence ingestion, part I: A semi-analytical approach</h2>
<h3>Kha, Jamie (1), Karimi, Mahmoud (1), Cao, Huong (1), Williams, Paul (1), Dylejko, Paul (2)</h3>
<p class="affilation">(1) Centre for Audio, Acoustics and Vibration, University of Technology Sydney, Sydney, Australia
(2) Platforms Division, Defence Science and Technology Group, Melbourne, Australia</p>
<p><b>ABSTRACT</b><br>
Airfoils that are incident to turbulent flow will experience unsteady lift. Typically, the turbulent flow interacting with the leading edge of the airfoil will induce a pressure jump, resulting in lift fluctuations that are stochastic in nature. The phenomenon of turbulence interaction of the leading edge can be modelled by Amiet's theory of an aerodynamic gust. In this work, for the system to be amenable to analytical analysis, the airfoil is modelled as a cantilever thin panel. The transverse motion of the cantilever panel is predicted by employing a thin plate theory as its governing equation. The governing equations are then solved by a modal decomposition in its in-vacuo mode shapes. The in-vacuo mode shapes can be approximated by a free vibration analysis using the semi-analytical Trigonometric Ritz method, where a sum of trigonometric admissible functions estimates the mode shapes. Combining the semi-analytical framework to predict the response of the panel with Amiet's theory of turbulent flow, vibrations of the cantilever panel due to turbulence ingestion can be efficiently resolved. The predicted vibration responses are compared against the Uncorrelated Wall Plane Wave (UWPW) technique for verification. The UWPW approach involves converting the random excitation into a set of deterministic uncorrelated plane waves that approximate the wall pressure field associated with the target random excitation. These wall pressure fields can then be used as an input to excite a structure, either through semi-analytical models or in a finite element model. The presented semi-analytical approach can serve as a framework for investigating vibration responses of more complex geometries with turbulence ingestion.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p39.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p21" class="affilation"></a>Radial vibration theory for thick-walled Hookean elastic hollow spheres with large strains and immersed in an incompressible fluid</h2>
<h3>McMahon, Darryl</h3>
<p class="affilation">Curtin University</p>
<p><b>ABSTRACT</b><br>
This paper exploits the results of a previous paper (Proceedings of Meetings on Acoustics, DOI https://doi.org/10.1121/2.0001819) that develops the theory of thick-walled Hookean elastic hollow spheres not limited by small strain approximations. Large strain elasticity theory may give some insights into soft elastic bodies subjected to high pressures such as deep underwater. An essential requirement for large strains is to transform the linear elasticity equations into terms of displaced radii rather than un-displaced radii as usually done. Geometry makes the combined stress and strain equations nonlinear however they can be solved numerically, and in some cases analytically. For small strains the solutions agree with Lame's solution for elastic spheres. The previous paper solved analytically the radial vibration (breathing mode) problem for the simplest case, Poisson ratio equal to zero and an incompressible inner core. A nonzero Poisson ratio makes the solution more complicated to derive of the effective spring constant and radial vibrational mass for a harmonic oscillator equivalent to the sphere. The effective spring constant only needs to consider displacements at the outer surface whereas the radial vibrational mass requires integrating the kinetic energy over the thickness of the sphere. This integration is analytically feasible only for certain values of a nonzero Poisson ratio. For simplicity in this paper, the sphere's inner hollow does not exchange energy with the elastic material. This applies to two hollow types, an incompressible core and a vacuum. The spring constant, radial vibrational mass and resonant frequency are plotted versus the Poisson ratio and sphere's outer surface pressure.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p21.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p107" class="affilation"></a>Noise and Health in children (in a broader environmental context)</h2>
<h3>van Kamp, Irene</h3>
<p class="affilation">Sustainability, Environment and Health, National Institute for Public Health and the Environment, Bilthoven, Netherlands</p>
<p><b>ABSTRACT</b><br>
Environmental noise is a growing public health problem in a rapidly urbanising world. Fetuses and neonates, children and adolescents can be considered as sensitive to noise because of their continuous physical and cognitive development. Early exposures might have serious effects later on in life and the concept of life-course exposure helps to study the impact of the physical (e.g., acoustic) and social environment on cognitive development and health in young people over time. Life course can be subdivided in different life phases and usually these are based on age and developmental stages. In some life phases people are more susceptible for environmental health effects than in others -so called sensitive periods. It is also possible that health effects of a sensitive period are co- affected by factors during later phases. In that case we speak of a domino effect. Children thus form an important group where environmental quality is concerned and early prevention of diverse environmental effects can have large health benefits also later on in life. Despite of this, children and adolescents have systematically been understudied in the field of environmental epidemiology and the noise field. This paper summarizes the existing knowledge on how children's short and long term health and cognitive development are affected by noise. Some mechanisms are discussed placing noise in the broader environmental context. Based on this overview we try to convey the message that the noise environments children grow up in have serious long-term effects on their learning and health. Intervention at an early age could benefit society as a whole by enhancing health and education outcomes, thus also addressing the contextual and root causes of social inequalities.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p107.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p17" class="affilation"></a>The Study of an Innovative Sound Absorbing Mechanism for Low-Frequency Sound</h2>
<h3>Law, Harvey (1), Kierzkowski, Marek (1)</h3>
<p class="affilation">(1) Dr</p>
<p><b>ABSTRACT</b><br>
This paper presents the development and evaluation of an innovative mechanism for absorbing low-frequency sound, a challenge that stems from the long wavelengths associated with these frequencies. Traditional methods of sound absorption rely on thick materials to achieve effective attenuation, which can be impractical in environments with spatial limitations. This study aims to address the growing demand for materials that can absorb low-frequency sound while maintaining minimal thickness, offering solutions for various engineering and architectural acoustic applications. Two configurations of thin membrane systems were tested—one with high airflow resistivity and the other with low airflow resistivity—integrated into materials with thicknesses of 24mm and 12mm. The role of an air gap in enhancing the acoustic performance of these membrane systems was also investigated. The results of these tests are thoroughly reviewed and compared, with a focus on the membrane thickness, airflow resistivity, and the impact of the air gap on sound absorption efficiency. Potential applications of these systems in real-world acoustic scenarios are discussed, and directions for further research are recommended to optimize these thin, space-efficient mechanisms for broader use.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p17.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p58" class="affilation"></a>Acoustic testing of JBN Ceiling Speaker System installed in-situ.</h2>
<h3>Raymond, Desmond (1), Castillo, Camilo (1)</h3>
<p class="affilation">(1) MAAS</p>
<p><b>ABSTRACT</b><br>
For the purposes of determining the performance of the JBN SoundCeiling, RSA measured the noise levels from the speaker system. The main emphasis is to measure the noise level output of the speaker system installed horizontally (ceiling configuration) and at varying distances.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p58.pdf" target="_blank"> Full Paper</a></p>
<hr>
<h2><a name="p69" class="affilation"></a>Sound masking system design and specification</h2>
<h3>Short, Megan</h3>
<p class="affilation">Soundmask Global Pty Ltd</p>
<p><b>ABSTRACT</b><br>
Every sound masking system requires a design customised to the space. However, without an understanding of good system design, specifications may be difficult to implement, and the installation may be unsuccessful. This paper introduces the basics of sound masking technology, identifies common misconceptions about the technology, and shares some simple rules to apply when specifying a sound masking system. The paper covers the importance of end user experience and offers the theory of sound mask system design along with practical examples and case studies of successful designs and installations. Applying this knowledge to each specification will give each installation the best chance of sound masking success.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p69.pdf" target="_blank"> Full Paper</a></p>
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<h2><a name="p81" class="affilation"></a>Design of an instrumented, modular insect arena for motion analysis and measuring ground reaction forces of small arthropods</h2>
<h3>Chahoud, Omar (1), Sansom, Travers (1), Wohrl, Toni (2), Oberst, Sebastian (1)</h3>
<p class="affilation">(1) University of Technology Sydney
(2) Institute for Zoology and Evolutionary Research, Jena</p>
<p><b>ABSTRACT</b><br>
The measurement of ground reaction forces in small arthropods has significantly advanced our understanding of their locomotion and gait adaptations in various environments and behaviours. These forces, in the lower milligram range, require precise instruments such as a miniature force plate for accurate measurement. A miniature force plate is a miniature tread plate mounted on a suspension structure, equipped with sensors to capture strain, and convert it into normal and lateral force components. Inspired by Reinhardt and Blickhan (2014) this project was aimed to develop an instrumented, modular arena to enhance the use of miniature force plates in arthropod bioassays and to adapt it to be applicable to smaller arthropods than European red wood ant (Formica rufa) as used in previous studies. Also, the experimental setup is sought to be capable of capturing high-resolution images with millisecond precision, synchronised with strain gauge data from the miniature force plate. The arena's narrow structure and removable floor increased the likelihood of leg-plate contact during experiments and facilitates rapid bioassay setup. The synchronised video and signal capture offer potential for advanced calibration methods in the future. The developed arena successfully captured images of small arthropods interacting with the structure, provides detailed top-down and side views of the insect anatomy which will be useful for future morphological studies. With the current setup we show the potential to measure ground reaction forces in arthropods weighing only a few milligrams, providing potentially key insights into the biomechanics and motion of insects, critical for the design of bio-informed micro-robotic systems.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p81.pdf" target="_blank"> Full Paper</a></p>
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<h2><a name="p111" class="affilation"></a>Review of audio compression formats for post-processing</h2>
<h3>Hall, Ben</h3>
<p class="affilation">Instralabs</p>
<p><b>ABSTRACT</b><br>
This paper investigates the impact of audio compression on the analysis of noise metrics using sound level meters. Various audio compression formats, including MP3, AAC, Ogg Vorbis, Opus, FLAC, ALAC, WavPack, and Speex, are applied to a series of test signals. Key noise metrics such as Leq, Lmax, Lmin, SEL,, statistical percentiles and 1/3 octave band analysis were compared</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p111.pdf" target="_blank"> Full Paper</a></p>
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<h2><a name="p110" class="affilation"></a>Comparison of data transmission protocols for remote and real-time environmental monitoring</h2>
<h3>Hall, Ben</h3>
<p class="affilation">Instralabs</p>
<p><b>ABSTRACT</b><br>
Environmental monitoring systems, particularly those involving remote sensors, rely heavily on efficient data transmission protocols to deliver real-time information for centralized analysis. This paper provides a comparative analysis of six key data transmission protocols—MQTT, HTTP, FTP, WebSockets, RPC, and WebDAV—assessing their suitability for remote and real-time environmental monitoring applications. The comparison focuses on four critical factors: connection overhead, latency, power consumption, and connection stability. Our analysis reveals that MQTT and WebSockets are the most efficient choices for real-time, low-power applications</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p110.pdf" target="_blank"> Full Paper</a></p>
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<h2><a name="p108" class="affilation"></a>A microactuator device to mimic ant vibrations for termite deterrence on life plants</h2>
<h3>Oberst, Sebastian (1), Tofigh, Farzad (1), Lai, Joseph C.S. (2), Evans, Theo A. (3)</h3>
<p class="affilation">(1) UTS
(2) UNSW
(3) UWA</p>
<p><b>ABSTRACT</b><br>
Annual termite damage exceeds US$ 40 billion worldwide, significantly impacting housing, wooden infrastructure and agriculture. While termites are beneficial to general soil quality, it costs millions of dollars in losses annually in crop yield (fruit, nuts) in Australian plantations and reduction in timber harvests by an estimated 25%. Often damaged plants do not survive termite attacks, especially when saplings are contacted. The only known treatment is the excessive application of chemical controls, such as Fibronil (Phenylpyrazole chemical that affects the insect's nervous system) to the soil and is absorbed by the plants. However, Fibronil, while effective against termites also damages significantly other insects such as pollinators and causes chronic health problems in humans; hence it has been banned in the EU. <br>
<br>
To overcome this problem arising from chemical treatments, a non-chemical termite control system that is cheap and effective is being sought. Since termites are eusocial insects, which live in colonies of up to several million individuals and communicate their actions and decisions largely through vibrations, a vibration-based repellent has been envisaged.<br>
<br>
Due to the fast-changing nature of the signals, which is in the order of nanoseconds, a circuitry system, based on microcontroller and piezoelectric actuation, has been designed (MiAC-S). A mathematical model of a predatory ant based on the traditional SLIP/BSLIP biomechanical model of bipedal walking is chosen here, assuming a tripod walking and running gait. The model is experimentally validated and implemented on an STM32 micro-controller. MiAC-S is then tested for feasibility in a food-choice bioassay setting, using the voracious Giant Northern termite (Mastotermes darwiniensis) on Mango (Mangifera indica) and dwarf Macademia (Macademia integrifolia) saplings in a greenhouse and controlled environmental chamber setting.<br>
<br>
Preliminary results indicate that MiAC-S can effectively influence M. darwiniensis foraging behaviour based on vibrations. Most of the successful setups show that termites moved more soil to the non-signal side (control); if soldiers were found, they were on the signal side, while if nymphs (neotenic differentiation) were present, they were found on the control side. Overall, significantly more termites were found on the control side than on the signal side. If termites were found in the soil of the plant, they were on the signal-side and mostly at the root complex furthest away from the stem closer to the water reservoir. While sample numbers remain low the results are encouraging and highlight the potential of using vibration-based termite control in horticulture and agriculture.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p108.pdf" target="_blank"> Full Paper</a></p>
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<h2><a name="p56" class="affilation"></a>Investigation of the Viability of Mobile Smartphones as Sound Level Meters</h2>
<h3>Wu, Chenxi (1), Chen, Kanvin (1)</h3>
<p class="affilation">(1) NDY</p>
<p><b>ABSTRACT</b><br>
Modern mobile smartphones have long had software applications which have extended their capabilities, including the use of the built-in microphones to measure noise levels. The accuracy of smartphones for this application are however debateable. This paper aims to further analyse this by conducting tests using a controlled noise source and Class 1 sound level meters acting as a reference noise level to determine the performance of several phone and app combinations to provide some insight to the accuracy of such devices for this application. Various variables were investigated, including the performance of phones in measuring a broadband pink noise source as well as the accuracy of the devices in measuring noise at particular frequencies across the octave band range. Calibration functions within the apps were also explored, with both broadband and frequency analysis done both pre- and post-calibration to determine the effect this had on the measured results.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p56.pdf" target="_blank"> Full Paper</a></p>
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<h2><a name="p80" class="affilation"></a>Design of an anechoic termination for an open ended duct</h2>
<h3>Finlay, Thomas (1), Leav, Orddom (1), Moore, Stephen (1)</h3>
<p class="affilation">(1) Defence Science Technology Group</p>
<p><b>ABSTRACT</b><br>
Anechoic terminations of ducts are used in acoustic testing platforms, such as specified in ISO 5136, to reduce the effect of acoustic waves reflected at the outlet from impacting the characterisation of test specimens. In cases where duct elements are characterised in the presence of flow, the anechoic termination must not impose a significant flow restriction. In ISO 5136, an anechoic termination with an open outlet is required and the standard recommends designs for the anechoic termination. However, there is very little background or references provided in the standard to justify the anechoic termination design. This paper investigates the effect of different outlet geometries and lining materials on the outlet reflection coefficient for no flow in the duct. A finite element model is developed using COMSOL software and validated against analytical models of unflanged open ended ducts, before being used to find reflection coefficients for different outlet conditions. These different outlet geometries include conical and catenoidal horns. A poroacoustic liner is added to the diverging section of the horns to investigate the effects of different materials. A general relationship between the relative horn size and reflection coefficient is found for each case, with the effect of poroacoustic liners found to be very important in minimizing reflection coefficient. Horns truncated in diameter are also modelled and results show that horn truncation can improve the anechoic response over a wide frequency range. The research provides a numerical framework for developing an anechoic outlet that can be used in systems where flow is present.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p80.pdf" target="_blank"> Full Paper</a></p>
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<h2><a name="p55" class="affilation"></a>Innovative design of façade elements to limit wind-induced noise in buildings</h2>
<h3>Florent, Masson (1), Pierre, Chassagne (2), Agreli, Henrique (1)</h3>
<p class="affilation">(1) Metravib Engineering
(2) AIA Ingéniérie</p>
<p><b>ABSTRACT</b><br>
Wind-induced noise is often overlooked in building design. This noise can be generated by wind blowing across façade elements or through the various gaps inside buildings. Noise generated by wind-affected façade elements, particularly at higher wind speeds, has received increasing attention since the 2010s. In this paper a comprehensive literature review is carried out to draw general rules for limiting wind-induced noise in buildings. Next, an innovative design was proposed by Metravib Engineering for the Rabat Ibn Sina hospital designed by AIA Ingénierie. A dynamic analysis of these sunshades was then verified using the finite element method to ensure there was no vibro-acoustic coupling between wind excitation and the sunshade's structural modes. Finally, wind tunnel tests confirmed that the noise induced by these façade elements was under control and did not cause any particular annoyance.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p55.pdf" target="_blank"> Full Paper</a></p>
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<h2><a name="p109" class="affilation"></a>Hearing tests in baleen whales</h2>
<h3>Dunlop, Rebecca</h3>
<p class="affilation">University of Queensland</p>
<p><b>ABSTRACT</b><br>
Despite increasing evidence that underwater anthropogenic noise has negative consequences on baleen whale hearing and behaviour, currently there are no direct data available on mysticete hearing in noise. Baleen whale hearing sensitivity can be assessed in several ways: (1) assessment of the frequency of their vocalisations; (2) functional models based upon auditory anatomy; (3) the performance of electrophysiological hearing tests and (4) using behavioural responses to sound exposures. Currently, there are two ongoing experiments, running in tandem, which aim to measure hearing range and sensitivity in two species of baleen whale; the minke whale (Balaenoptera acutorostrata) and the humpback whale (Megaptera novaeangliae). Each study uses a different methodology. The minke whale study is attempting to use electrophysiological audiometry, which measures neural activity when the auditory system is stimulated by sound. Electrophysiological studies are regularly performed in small, toothed whales, given these species can be maintained in captivity. These experiments are obviously more challenging to perform in baleen whales, given they cannot be kept in captivity, meaning animals must be caught and restrained. The advantage of these approach is that species-specific unmasked hearing audiograms. This talk will focus on the second experiment. The humpback whale experiment uses a behavioural response paradigm to test the sensitivity of migrating humpback whales to sound in relatively quiet, natural ocean noise. Behavioural response experiments do not rely on restraining and training the animal and instead rely on the natural responses of animals to noise sources. In this sense, acoustic behavioural response studies in whales are similar to behavioural observation audiometry in humans. One disadvantage of this approach is that subjects may not respond at detection threshold but at some level above detection. The other disadvantage, with regards to whales, is that these experiments are carried out in the open ocean, a noisy environment, meaning signals across the frequency range of good hearing sensitivity are likely to be masked, preventing measurement of unmasked detection thresholds. However, given that stakeholders are tasked with predicting sound exposure impacts, and developing mitigation policies, in potentially noisy, real-world environments, measures of baleen whale hearing in ocean noise, and their response thresholds, are useful metrics. In that sense, the minimum response levels from the humpback whale study were used to make inferences about frequency-dependent masked hearing thresholds in humpback whales, the first empirical measures of humpback hearing in ocean noise.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p109.pdf" target="_blank"> Full Paper</a></p>
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<h2><a name="p121" class="affilation"></a>Acoustic-Gravity Waves, Theory and Applications</h2>
<h3>Kadri, Usama</h3>
<p class="affilation">Cardiff University</p>
<p><b>ABSTRACT</b><br>
Acoustic-gravity waves(AGWs)are critical to understanding a wide range of oceanographic and geophysical phenomena, including tsunamis and microseisms. These waves, governed by the interplay between gravity, compressibility, and elasticity, propagate through the ocean and atmosphere, transporting energy over long distances with minimal attenuation. Recent advancements in AGW theory, including resonant triad interactions and the effects of seabed elasticity, have provided deeper insights into their behaviour and practical applications. This paper presents the theoretical foundations of AGWs and highlights their role in early warning systems, tsunami mitigation, and potential energy harnessing.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p121.pdf" target="_blank"> Full Paper</a></p>
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<h2><a name="p23" class="affilation"></a>Audio-visual interactions in environmental noise perception and the link to urban greening</h2>
<h3>Van Renterghem, Timothy</h3>
<p class="affilation">Ghent University, Department of Information Technology, WAVES research group, Technologiepark 126, B 9052 Gent-Zwijnaarde, Belgium</p>
<p><b>ABSTRACT</b><br>
Although physical noise abatement (decibel reduction) is possible with well-designed green infrastructure, the effects of urban greenery on sound perception are often stronger and easier to obtain. This can be attributed to audio-visual interactions, which play a crucial role in environmental noise perception. There is substantial evidence that compelling visual elements, such as greenery, can mitigate the negative effects of environmental noise exposure. Green window view, or seeing outdoor vegetation through the windows of one's dwelling, has been extensively studied before with relation to self-reported road traffic noise annoyance. Studies include long-term noise annoyance assessed at the dwelling through surveys, but also virtual reality experiments in the lab. To incorporate this concept into urban sound planning, design guidelines are needed to optimize the benefits of positive audio-visual interactions. Two recent virtual reality experiments will be discussed, aiming to determine the optimal quantity and quality of greenery. Further research gaps are identified, including the need for more grounded equivalent level reductions to quantify the effect easily, the expected non-linearity of this effect, and the influence of personal factors.</p>
<p class="affilation"><img src="../images/pdfview_small.gif" alt="PDF" border="0" style="width: 28px; height: 31px;"><a href="papers/p23.pdf" target="_blank"> Full Paper</a></p>
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