TUESDAY MORNING, 8 MAY 2018 NICOLLET C, 9:00 AM TO 11:50 AM Session 2aAAa ...

64 Pages·2017·0.46 MB·English

TUESDAYMORNING,8MAY2018 NICOLLETC,9:00A.M.TO11:50A.M.
Session2aAAa
ArchitecturalAcousticsandASACommitteeonStandards:AcousticsofLobbies,Atria,Stairways,
Corridors,Pre-function,etc.
LoganD.Pippitt,Chair
MarvinHall,1465JayhawkBlvd.,Lawrence,KS66045
Chair’sIntroduction—9:00
InvitedPapers
9:05
2aAAa1.Thefaceofthefacility.BrandonCudequestandK.AnthonyHoover(McKayConantHoover,5655LinderoCanyonRd.Ste.
325,WestlakeVillage,CA91362,[email protected])
Lobbiesandatriaareafacility’sinitialdestination,thepointofdeparture,theinformationcenter,andthesecuritycheckpoint.They
defineabuilding’saesthetic,connecttotherestofthefacility,requirehighspeechintelligibilityatkeylocations,anddemanddurability.
Therequirementscanfluidlyfluctuatethroughoutdesign,andtheacousticsneedtokeeppace.Thispaperwilldiscussdifferentprojects
wherethelobbywascentraltoasuccessfuldesign.Highlightsincludeahospitalatrium,whereinabalancewasstruckbetweenspeech
intelligibilityandspeechprivacy;anairportconcoursewheretheprospectoftilegroutlineswascarefullyconsidered;andagiantcourt-
houselobbywithdesigngoalsatoddswithdesignstandards,andwithbridgesprovidingacoustical“shade”forsecurityguards.
9:30
2aAAa2. Acoustically neglected and ignored building spaces. Megan Stonestreet (Architecture, Univ. of Kansas, University of
Kansas,Lawrence,KS66045,[email protected])
Oftenneglectedandignoredbuildingspacesinregardtoroomacousticsandbuildingnoisearecorridors,stairways,andlobbies.For
example,reverberantcorridorsinschoolteachingbuildingsareoftennoisyandprovideanundesirableacousticconnectionbetween
classrooms; stairways are typically reverberant spaces that act as vertical corridors and are generally unpleasant spaces; lobbies are
actuallymultipurposespacesthatserveasentrance,exit,andgatheringspaces,andforperformancefacilities,theyarealsousedasper-
formance spaces. Examples of each of these building spaces will be discussed along with acoustic data and practical acoustic
requirements.
9:55
2aAAa3.Casestudiesoftwoatriatobeginaconversationregardingtheimportanceofacousticalperformanceoftransitional
spaces.MichelleHueyandMichael(Mick)Barnhardt(D.L.AdamsAssoc.,1536OgdenSt.,Denver,CO80218,[email protected])
Transitionalspaces,suchaslobbiesoratria,arelargelyforgottenspacesregardingroomacoustics.Thesetransitionalspacesare
widelyusedforpresentations,meetings,andparties/gatherings.Lobbiesandatriaareoftenconnectedtohallwaysandadjacentoffice
clusters,wheresoundcanpropagatetoareasfarawayfromthesource.Withtheever-increasingneedfortransitionalspacestoalsoact
asgatheringspaces,itisimportanttobeginadiscussionofacousticalstandardsintransitionalspaces.Thispaperdiscussestwocase
studiesconductedbyD.L.AdamsAssociates:(1)Anatriumwithakitchenanddiningareausedforparties,gatherings,meetings,and
throughoutthedaybyemployees;(2)anatriumwithacommercial-gradekitchenatthecenterusedformeetings,lunchtime,gatherings,
andspecialevents.Thispaperincludesdiscussionsofnoisepropagation,noisebuildup,reverberationtime,andabsorptivetreatments
withintransitionalspacesandhowtomakethespacesworkacoustically,whileisolatingthemfromadjacentareas.
10:20
2aAAa4. Case study of acoustics in two very large atriums. Timothy Foulkes (Cavanaugh Tocci Assoc., 327 Boston Post Rd.,
Sudbury,MA01776,[email protected])
Tworecentprojectshaveinvolvedverylargespaceswithpredominantlyhardfinishes.Oneassignmentwastodevelopanacoustic
treatmentplanforanexistingsixstoryinteriorcourtyardwithinanofficetower.Thisspace,averyformaldesignfinishedinmarble,
woodpaneling,andglass,hada7secondreverberationtime.Thecourtyardwasavailableasaloungespacetoalltenantsofthebuilding
butwasbarelyutilized.Wewerepartofadesignteamhiredbythebuildingownerstoupdatethecourtyardandmakeitmoreuser
friendly,includingimprovementintheacoustics.Theotheratriumwaspartofanewproject—asevenstoryglassenclosurewithacon-
cretefloor.Thisatriumservesmanydifferentfunctionsincludingthemainentranceandsecuritylobby,diningspace,informalmeeting
space,andlounge.Theacousticsweremitigatedbytheirregularshape,areasofcarpetonthebalconies,andlimitedareasofacoustic
1764 J.Acoust.Soc.Am.,Vol.143,No.3,Pt.2,March2018 175thMeeting:AcousticalSocietyofAmerica 1764
paneling.Thenewatriumisasuccessandithasbecomethelivingroomandhubforthislargebuilding.Itiswellusedthroughoutthe
workdayforallofthepurposesmentionedaboveandmore.Renovationsfortheotherspacearestillindesignasoftheabstractdead-
line,buttheremaybefinishedintimefortheSpringASAmeeting.Thepresentationwillincludeadiscussionofthedimensionsandfin-
ishes,acousticpriorities,designchallenges,acousticmeasurements,andsubjectivecomments.
10:45
2aAAa5. Measured acoustic conditions in the common spaces of two educational buildings at the University of Nebraska–
Omaha.SamuelH.UnderwoodandLilyM.Wang(DurhamSchoolofArchitecturalEng.andConstruction,Univ.ofNebraska-Lincoln,
1110S.67thSt.Omaha,NE,Omaha,NE68182-0816,[email protected])
Thispaperpresentsresultsfromanacousticalcasestudyoftheatria,corridors,stairways,andothercommonspaceswithintwo
buildingslocatedonthecampusoftheUniversityofNebraska-Omaha:thePeterKiewitInstituteandtheBarbaraWeitzCommunity
EngagementCenter.Bothbuildings,whileeducationalinnature,differdrasticallyinacousticaldesign.Impulseresponses,noiselevels,
andtransmissionlossinbothfacilitiesaremeasuredandtheresultingacousticmetricsarecomparedtorecommendedvaluesforthe
respectivespaces.Descriptionsofeachbuilding’sarchitecturalfeaturesarepresentedandlinkedtothemeasurementresults.Inparticu-
lar,manyspacesinthePeterKiewitInstituteweredesignedtoexposethebuildingsystems,andthelackofacousticalproductssuchas
acousticalceilingtileresultsinhighernoiselevelsthannormallyexpected.TheWeitzCenter,however,wasdesignedwithgreatempha-
M
sisplacedonachievingoptimalindoorenvironmentalconditions.Theresultsofthiscasestudysupporttheimportanceofappropriate A
acousticdesignatria,corridors,stairways,andothercommonspacesineducationalsettings. E.
U
11:10 T
a
2aAAa6.ThearchitecturalrejuvenationofCanada’sNationalArtsCentre:Thefunctionofpre-function.RobinS.Glosemeyer 2
PetroneandMarcusR.Mayell(ThresholdAcoust.com,53WJacksonBlvd.,Ste.815,Chicago,IL60604,robin@thresholdacoustics.
com)
WhenCanada’sNationalArtsCentreopenedin1967,theBrutalistarchitecturestyleofitserayieldedafortressforthearts.AsCan-
adacelebratesitssesquicentennial,a$110M(Canadian)architecturalrejuvenationprocessistransformingtheinwardfacingfortress
intoalluringbeaconattheheartofthecapital.Expandedpublicspacesenvelopedintransparentfacadesformmultiplepre-function
spacesthatvisuallyspillintooneanothertoconveytheconstantactivityofCanada’sincubatorfortheperformingartstothepatrons
withinandthesurroundingcity.Thedesireforvisualtransparency,thebuilding’sdesignationasaNationalHistoricSiteofCanada,and
needforsimultaneousprogrammingoftheperformanceandpre-functionsspacesprovidednoshortageofacousticchallenges.
ContributedPaper
11:35 surveyedeightdifferentatriumandlobbyspacesinDenverandusedthis
reverberationtimeandbackgroundnoisedatatodevelopanappropriate
2aAAa7.Creatingrealisticdesigngoalsthroughtheuseoflocally-meas-
rangeofreverberationtimes,foragivenroomvolume,coveringmostof
uredreverberationtimeandbackgroundnoisedata.MattWhitneyand
the common uses for atriums and lobbies. These ranges help provide
Ted Pyper (K2, 5777 Central Ave., Ste. 225, Boulder, CO 80301, matt@
guidance to both the design teamand the end user on design goals and
k2avt.com)
expectations for these spaces. This presentation will present these data,
One of the major difficulties in the design process of an atrium or aswellassubjectiveimpressionsandarchitecturaldesignofeachofthe
lobby is providing points of reference to both the architect and the end spaces,anddescribehowK2usedthisinformationtoinitiateproductive
user to help drive the conversation on an acceptable reverberation time conversationswitharchitectsandendusersandproducerealisticdesign
and background noise level for the projected use cases. K2 recently goals.
1765 J.Acoust.Soc.Am.,Vol.143,No.3,Pt.2,March2018 175thMeeting:AcousticalSocietyofAmerica 1765
TUESDAYMORNING,8MAY2018 NICOLLETA,9:00A.M.TO12:00NOON
Session2aAAb
ArchitecturalAcoustics:StudentDesignCompetition(PosterSession)
DavidS.Woolworth,Cochair
Roland,Woolworth&Associates,356CR102,Oxford,MS38655
AndrewN.Miller,Cochair
Bai,LLC,4006Speedway,Austin,TX78758
TheTechnicalCommitteeonArchitecturalAcousticsoftheAcousticalSocietyofAmericawithsupportfromtheRobertNewmanStu-
dentAwardFundandtheNationalCouncilofAcousticalConsultantsaresponsoringthe2015StudentDesignCompetitionthatwillbe
professionallyjudgedatthismeeting.
Thecompetitioninvolvesthedesignofanewmunicipalbuildingincludingacourtroomandacommunityhall.Thesubmitteddesigns
willbejudgedbyapanelofprofessionalarchitectsandacousticalconsultants.AnawardofUS$1250willbemadetothesubmitter(s)of
thedesignjudged“firsthonors.”FourawardsofUS$700eachwillbemadetothesubmittersoffourentriesjudged“commendation.”
TUESDAYMORNING,8MAY2018 LAKESHOREB,8:00A.M.TO11:55A.M.
Session2aAB
AnimalBioacousticsandASACommitteeonStandards:HistoryofAnimalBioacoustics
DavidK.Mellinger,Chair
Coop.Inst.forMarineResourcesStudies,OregonStateUniversity,2030SEMarineScienceDr.,Newport,OR97365
Chair’sIntroduction—8:00
InvitedPapers
8:05
2aAB1.ABriefhistoryofavianbioacoustics.RobertDooling(Psych.,Univ.ofMaryland,BaltimoreAve.,CollegePark,MD20742,
[email protected])andMichealL.Dent(Psych.,Univ.ofBuffalo,Buffalo,NY)
AproperhistoryofavianbioacousticswouldreferenceearlynaturalistssuchasAristotle,PlinytheElder,andotherswhoobserved
thatbirdsnotonlyhaveacutesensesbutthattheyalsolearntheirvocalizationswithreferencetoauditoryinformationandexhibitparal-
lelswithhumanspeech,language,andmusic.Ontheproductionside,thedevelopmentofthetaperecorderfollowedbythesoundspec-
trograph enabled researchers to precisely record, preserve, analyze, and quantify the characteristics of the amplitude and spectral
envelopeoftheacousticsignalswhichbirdsusetocommunicate.Inthe1950sThorpe,andlaterMarler,tackledthedevelopmentof
vocallearninginbirdsandthenuancesofindividualandspeciesdifferences,whichbeganthemoderneraofavianbioacoustics.Almost
simultaneously,ontheperceptionside,theconfluenceofSkinnerianconditioningmethods,signaldetectiontheory,andthefirstlabora-
toryminicomputerslaunchedthemoderneraofanimalpsychophysics,whichcontinuestothisdayinhelpingtounderstandthestriking
parallelsbetweenavianacousticcommunicationandspeechandlanguagelearninginhumans.
8:25
2aAB2.Ahistoryoffishbioacoustics.ArthurN.Popper(Univ.ofMaryland,Biology/Psych.Bldg.,CollegePark,MD20742,apop-
[email protected])andAnthonyD.Hawkins(LoughineLtd,Aberdeen,UnitedKingdom)
Awarenessoffishsoundproductiondatesbacktoancienttimes,andconcernabouteffectsofman-madesoundsonfishescanbe
tracedbackatleasttothemid17thcentury.Bytheendofthe19thcentury,themorphologyofthefishearhadbeenwelldescribed,but
experimentalstudiesofthehearingcharacteristicsdidnotbeginuntiltheearly1900s,whenParkerdemonstratedthatfishcandetect
1766 J.Acoust.Soc.Am.,Vol.143,No.3,Pt.2,March2018 175thMeeting:AcousticalSocietyofAmerica 1766
sounds.SubsequentworkbyvonFrischandhisstudents,includingDijkgraaf,determinedtherangeoffrequenciesthatfishescould
detect,andshowedthefishescandiscriminatebetweensounds.LaterworkinEuropeprovidedadeeperunderstandingofsounddetec-
tionmechanismswithEngerpioneeringexperimentsonfishesinthesea.ExperimentsintheseabySchuijf,Chapman,andothersdem-
onstrated that fish could discriminate sound directions. Meanwhile, in the U.S., Moulton, Tavolga, and their students documented
diversityinfishhearingcapabilities.Concurrently,studiesbyFish,Winn,Myrberg,Tavolga,andothersshoweddiversityinfishsounds,
anddocumentedthebehaviorsassociatedwithfishsoundproduction.Workbytheseinvestigators(andmanyothers)openedthefieldof
fishbioacoustics,andprovidedawealthofinformationthatstandstodayasthebasisformodernstudies.
8:45
2aAB3. Amphibian bioacoustics: From Arch to Zelick. Peter M. Narins (Integrative Biology & Physiol., UCLA, 621 Charles E.
YoungDr.S.,LosAngeles,CA90095-1606,[email protected])
Amphibianbioacousticsmaybethoughttohaveoriginatedwiththefirstpublishedacousticplaybackexperiments withfrogs60
yearsago.MartofandThompson(1958,Behavior13:243–258)andLittlejohnandMichaud(1959,Tex.Jour.Sci.11:86–92)showed
thatmalecallsofPseudacrisnigritainGeorgiaareeffectiveinattractingconspecificfemales,andthatfemalesofPseudacrisstreckeri
inTexascandiscriminateconspecificcallsfromheterospecificcalls,respectively.Capranica(1965,JASA40:1131–1139)wasthefirst
toelectronicallysynthesizebullfrogcallsandtoelectronicallymodify(filter)themforuseasstimuliinacousticplaybackexperiments.
M
Sincethen,allhellbrokeloose.Reel-to-reel,cassetteandDATtaperecorders,werereplacedbywidebandportabledigitalmachinesca- A
pableofrecordingdirectlytoCFcardsand/ortohighcapacityinternalharddrives.Sophisticatedcallsynthesisandanalysisprograms E.
arewidelyavailable.AmphibiancommunicationhasbeenstudiedonsixcontinentsandMadagascarandwehavegainedamoresophis- U
ticatedappreciationoftheproductionandreceptionofamphibianairbornesignals.Nowthechallengeistofindnewandinterestingam- T
phibianbioacousticquestions, andfor inspiration, Ishallpresenta briefreviewof someofthenoteworthyexperimentsof thepast. a
2
[WorksupportedbyNSFgrant#1555734.]
9:05
2aAB4.Historyoftechnologyforstudyinganimalsoundandcommunication.DavidK.Mellinger(Coop.Inst.forMarineResources
Studies,OregonStateUniv.,2030SEMarineSci.Dr.,Newport,OR97365,[email protected])
New technology has always been used to listen to, study, and understand animal sounds. Early recording devices in the 1870s
employingwaxcylindersanddiscswerequicklyemployedforrecordingnaturesounds.Underwaterlisteningdevicesfromthe1910s
capturedmarineanimalsounds;interestinthesesoundsincreasedgreatlyafterWorldWarII,whennavaladvancesmadeunderwater
soundaccessibletosonaroperatorswhonotedthepresenceofcetaceansounds.Microphonetechnologyadvancedtothepointwhereul-
trasonicandeventuallyinfrasonicsignalswererecorded.Frequencyseparationandanalysiswasfacilitatedbytheinventionofthevo-
coderinthelate1930s,whichseparatedsoundintoanumberoffrequencybandsandenabled,forinstance,thediscoveryofmultiple
sourcesofsound(morethanonesyrinx)inbirdvocalizations.Thegreatestleapinfrequencyseparationcamewiththediscoveryofthe
FastFourierTransformanditsapplicationondigitalcomputersformakingspectrograms;sincethe1970s,thesesimplegraphicdisplays
havemadeitpossibletolookatsoundsignalsstatically,greatlyfacilitatinganalysis.Advancesindigitalmulti-channelrecordinghave
improvedourabilitytolocalizeanimalsandstudycommunicationnetworks.Advancesinanalysissoftwarecontinuestoimproveour
abilitytointerpretsoundsofanimals.
ContributedPaper
9:25 ocean thermometry research and submarine detection over ocean basins
broughtadditionalconcernsintheearly1990sonpotentialimpactsonma-
2aAB5. A brief history of our understandings on underwater noise
rine mammals from intense sources. Around late 1990s, several ad-hoc
impactstomarinelifeandtheevolutionofitsregulatoryprocessinthe
noiselevelswereadoptedasacousticimpactthresholdsofmarinemammals
United States. Shane Guan, Amy R. Scholik-Schlomer, and Jacqueline
byregulatoryagenciesintheU.S.Severalcetaceanmassstrandingevents
Pearson-Meyer (Office of Protected Resources, National Marine Fisheries
thatwerecoincidentalwiththemid-frequencymilitarysonaroperationsand
Service, 1315 East-West Hwy., SSMC-3, Ste. 13700, Silver Spring, MD
theincreasedawarenessofoceannoisepollutionacceleratedresearchinthis
20910,[email protected]) fieldinthe21stCentury.Numerousstudiesonhearingsensitivityandnoise
Ithasbeenlongunderstoodthatelevatednoiseisdetrimentaltosignal inducedtemporarythresholdshiftorphysicalinjuriesonvariousmarineani-
detection by the anti-submarine warfare community. However, it was not maltaxaledtonewsophisticatedregulatoryguidelinesonassessingunder-
untiltheearly1970sthatsimilarconcernswereraisedregardingmarinelife water noise impacts to marine life. In addition, recent understanding of
thatutilizesoundforvariouslifefunctions.The1980ssawsomeofthefirst soundscapesasenvironmentalqualityfactorsprovidesnewperspectiveson
studiesoneffectsofnoisefromoffshoreoilandgasexplorationanddevel- marinespeciesandecosystemconservation.
opment on marine mammals in Arctic waters. Low-frequency sources for
9:40–9:55Break
1767 J.Acoust.Soc.Am.,Vol.143,No.3,Pt.2,March2018 175thMeeting:AcousticalSocietyofAmerica 1767
InvitedPapers
9:55
2aAB6.TheOfficeofNavalResearchMarineMammalProgram,1990–2006.RobertGisiner(IAGC,5410SycamoreVillasDr.,
Kingwood,TX77345,[email protected])
ONRfirststoodupadedicatedmarinemammalresearchprogramin1990.TheinitialeffortwasledbyDanCosta,withthesupport
ofexperiencedONRprogramleaderslikeMelBriscoe,BernieZahuranec,andSteveZornetzer.Theauthorwasprivilegedtomanage
theprogramfrom1993to2006;aperiodofrapidexpansionofconcernaboutthemarineenvironmentaccompaniedbythedesiretoput
toolsforimprovedunderstandinginthehandsofscientistsanddecisionmakers.Theemphasisfromthestartwasonmulti-disciplinary
collaborations. Major research themes included hearing and exploration of Temporary Threshold Shift as a metric of auditory risk;
advancement of animal-borne scientific instruments(“tags“);advancementof ocean acoustic monitoringtechnologies,refinement of
field sound exposure experimental methods, and improvement of sound exposure models. Frequent external reviews, including four
NationalResearchCouncil(NRC)reviews,werevitaltothequalityandcredibilityoftheprogram.The2005NRCreviewonthePopu-
lationConsequencesofAcousticDisturbance(PCAD)isatextbookexampleofhowONR’sbasicresearchcontributionshavehadfar-
reachingconsequencesthatgreatlyexceededinitialexpectations.Theconvergenceofgrowingconcernaboutmanmadesoundinthe
oceanandtheONRmodelforqualityinbasicresearchhashadaprofoundimpactonourabilitytounderstandoceanbioacousticsandto
makebetterinformeddecisionsaboutthepotentialrisksposedbyhumanactivitiesinthemarineenvironment.
10:15
2aAB7.ThelastdecadeofbioacousticsattheOfficeofNavalResearch.MichaelWeise(OfficeofNavalRes.,875NRandolphSr,
Arlington,VA94598,[email protected])
ThegoaloftheONRMarineMammalsandBiology(MMB)programistoenableNavytoandmeetoperationaltrainingandtesting
objectivesinanenvironmentallyresponsibleandlegalmanner.TheONRMarineMammalsandBiologyprograminvestsinMonitoring
andDetectiontopicwiththegoalistoimprovemarinemammalmonitoringcapabilitiesovercurrentmethods.Developnewandexisting
technologysuchaspassiveacoustics,IR,andothers.Recentresearcheffortsonpassiveacousticsincludethedevelopmentandtestingof
newautonomoushardwareplatformsandsignalprocessingalgorithmsfordetection,classification,andlocalizationofmarinemammals.
Ultimately,theONRgoalistoadaptthosealgorithmsforuseonavarietyoffixed,towed,floating,andprofilingplatforms.Forexample,
overthelastseveralyearsONRhasadaptedtheuseofautonomousoceanglidersformarinemammalmonitoringtocreatethedesired
capabilityofpersistent,autonomous,passiveacousticmonitoringofanareaformarinemammalpresenceandabundancetoprovide
timely,reliable,accurate,andactionableinformationtosupportmarinemammalmitigationandmonitoring.AkeygoalofONRspon-
soredtechnologydevelopmentismakingthetechnologyavailabletothebroaderNavyandresearchcommunities.
10:35
2aAB8.ThehistoryofmarinemammalbioacousticsattheNavyMarineMammalProgram.DorianS.Houser(NationalMarine
MammalFoundation,2240ShelterIslandDr.,SanDiego,CA92106,[email protected]),JamesJ.Finneran,Keith
Jenkins,E.E.Henderson(USNavyMarineMammalProgram,SanDiego,CA),JasonMulsow,BrianK.Branstetter(NationalMarine
MammalFoundation,SanDiego,CA),PatrickMoore(NationalMarineMammalFoundation,SpringValley,CA),andStephenW.Mar-
tin(NationalMarineMammalFoundation,SanDiego,CA)
TheUnitedStatesNavyMarineMammalProgram(MMP)hasbeeninexistenceforover50years.Followingitsinception,thepro-
gramquicklybecameinvolvedinthestudyofmarinemammalsensorysystemsandbioacoustics.Earlystudiesincludedthepioneering
workofC.ScottJohnsoninobtainingthefirstbehavioralaudiograminadolphinandSamRidgway’selectrophysiologicalstudiesof
dolphin hearing and sound production. Marine mammal bioacoustic studies grew substantially in the decades following the MMP’s
inception,andincludednumerousinvestigationsintoodontocetebiosonar,pinnipedandodontocetehearing(usingbothbehavioraland
physiological methods), and the impact of human-made sound on the hearing, behavior, and physiology of marine mammals. The
MMP’sbioacousticresearchhassignificantlycontributedtotheNavy’senvironmentalstewardshipmandate(i.e.topredictandmitigate
theimpactofNavyactivitiesonmarinemammals),thedevelopmentofbio-inspiredsonarsystems,andtheabilitytoassessthehearing
capabilitiesofmarinemammalsinthewild,underhumancare,andinstrandedorrehabilitationscenarios.TheMMPcontinuesitsbioa-
cousticstudiestodaywithinvestmentsfocusedonbottlenosedolphinandsealionbioacoustics,butwithexpansiontothepassiveacous-
ticmonitoringofwildmarinemammals.
10:55
2aAB9.HistoryofmarinebioacousticsinFloridaandtheCaribbean.DavidMann(LoggerheadInstruments,Inc.,6576PalmerPark
Circle,Sarasota,FL34238,[email protected])
The diverse fauna of Florida and the Caribbean has long attracted scientists studying marine bioacoustics. The earliest studies
(1905–1945)inFloridaexaminedspeciesdistributionsandlifehistories.AfterWorldWarIIbioacousticsstudiesbeganinearnest.At
Marineland,whichopenedtosupportunderwaterfilming,Lillystudieddolphinvocalizationsandattemptedtolinkthemtobehavior.
MelbaandDavidCaldwellpioneeredstudiesonthedevelopmentofdolphinsignaturewhistles.Tavolgaperformedfundamentalwork
onsoundproductionandbehavioringobiesandmanystudiesonthehearingabilityoffishesatBimini,Marineland,andMoteMarine
Laboratory.Myrberg’sMiamilaboratoryshowedthatdifferentdamselfisheshaddistinctsounds.Inthe1960’s,Brederdocumenteddiel
andseasonalvariationinfishsoundproduction.Mostrecently,studieshavefocusedonwildanimals.WorkingwithWells’Sarasota
DolphinResearchProject,Tyack,Sayigh,andJanikhavecatalogedsignaturewhistlesandusedplaybackexperimentstostudysalient
features.FundamentalworkidentifyingsoundsproducedbyfishesbegunbyLobelhasspreadtoseveralresearchgroupsinFlorida,
USVI,PuertoRico,andtheCaymanIslands.Passiveacousticstudiesusingglidersshowthatmuchworkremainstoidentifythesources
ofunknownsounds.
1768 J.Acoust.Soc.Am.,Vol.143,No.3,Pt.2,March2018 175thMeeting:AcousticalSocietyofAmerica 1768
11:15
2aAB10.HistoryofbioacousticsresearchonaquaticandmarineorganismsinHawaii.WhitlowAu(Univ.ofHawaii,P.O.Box
1346,Kaneohe,HI96744,Kailua,HI96734,[email protected])
Modern bioacoustic research with aquatic animals began in Hawaii in the 1968–1969 period when three independent programs
started almost simultaneously. Two faculty members began studying various facets of hearing in fish at the University of Hawaii.
Anotherfacultymemberfromadifferentdepartmentestablishedalaboratoryinwhichdolphinhearingandecholocationwereamong
someofthetopicsstudied.TheNavystartedadolphinfacilitytotraindolphinstoperformNavyrelatedtasks.TheNavyprogramalso
includedresearchondolphinecholocationincludingastudycomparingtheperformanceoftwodolphinsandaStraza-500CTFMsonar
intargetdetection.TheNavyfacilityclosedin1993butsomeofthebioacousticsresearchwastransferredtotheUniversity’sHawaii
Institute of Marine Biology on Coconut Island about a mile from the former Navy facility in the same bay. The HIMB program
expandedintofieldresearchwithspinnerdolphinsandhumpbackwhales,andpassiveacousticmonitoringofmarineorganisms.The
localNationalMarineFisheriesServiceofNOAAbecameaclosepartnerinthePAMdevelopmentandstudies.Thispresentationwill
focusofthebioacousticresearchperformedwithmarinemammalshighlightingsomeofthemoreimportantfindingsandcontributions
tothefield.
11:35
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2aAB11.ThecentralroleofWoodsHoleOceanographicInstitution(WHOI)inmarinemammalbioacoustics.DouglasWartzok
(Dept.ofBiologicalSci.,FloridaInt.Univ.,11200SW8thSt.,Miami,FL33199,wartzok@fiu.edu)andG.CarletonRay(Environ.Sci., E.
U
Univ.ofVirginia,Charlottesville,VA)
T
WHOI researchers pioneered marine mammal bioacoustics. Schevill and Lawrence in 1949 made the first recordings of marine a
2
mammals,belugawhales,andin1956firstdemonstratedcetaceanecholocation.Schevilllaterconcentratedonthetaxonomyandbehav-
iorofcetaceanswhileWatkinsdevelopedthefirstportablehigh-frequencyrecorderandpassiveandactiveacoustictrackingsystems.
Ray,Watkins,andSchevillin1969presentedthefirstevidenceofsonginamarinemammal,thebeardedseal,linkedtothebehaviorof
malesinthebreedingseason.Watkins’papersonvocalizationsinformedagenerationofbioacousticiansonhowtointerpretsonograms.
HewasoneofthefirsttousetheNavy’sSOSUShydrophonearraytotrackcetaceanmovements.SchevillandWatkinsalsoinspiredthe
researchofothers,bothinrecodingmarinemammalsoundsandininterpretingsoundinbehavior.TyackledthedevelopmentoftheD-
Tag,whichsimultaneouslyrecordsvocalizationsandmovementsofcetaceans.KettenusedCATscanstodevelophearingmodelsfor
cetaceans.SayighadvancedknowledgeofdelphnidsignaturewhistlesandFristrupfurtherdevelopedtheconceptofsoundscapes.Wat-
kinsandSchevill’sdatabaseofmorethan20,000vocalizationsfrom70marinemammalspeciesnowresidesattheNewBedfordWhal-
ingMuseum,freelyavailabletothepublic.
TUESDAYMORNING,8MAY2018 GREENWAYA,8:00A.M.TO10:35A.M.
Session2aAOa
AcousticalOceanographyandUnderwaterAcoustics:AcousticSeabedCharacterizationI
DavidP.Knobles,Cochair
KSALLC,POBox27200,Austin,TX78755
PrestonS.Wilson,Cochair
Mech.Eng.,Univ.ofTexasatAustin,1UniversityStation,C2200,Austin,TX78712-0292
InvitedPapers
8:00
2aAOa1.Bayesiangeoacousticinversionforsedimentprofilesconsistingofageneralgradientoveralayeredsubstrate.StanE.
Dosso,Jos(cid:2)eeBelcourt(SchoolofEarth&OceanSci,UnivofVictoria,POBox1700,Victoria,BCV8W3P6,Canada,sdosso@uvic.
ca),JanDettmer(GeoSci.,Univ.ofCalgary,Calgary,AB,Canada),andCharlesW.Holland(Appl.Res.Lab.,ThePennStateUniv.,
StateCollege,PA)
ThispaperconsidersBayesiangeoacousticinversionanduncertaintyestimationforseabedprofilesconsistingofasmoothgradient
ofgeneralformoverlyingapotentially-layeredsubstrate.TheprofilegradientisparameterizedasalinearcombinationofBernstein-
polynomialbasisfunctions,withthepolynomialorderdeterminedobjectivelybyapplyingthedevianceinformationcriterion.Inthis
waytheformofthegradientisdeterminedbythedata,ratherthanbyasubjectivepriorchoice.Thesubstratebelowthegradientconsists
1769 J.Acoust.Soc.Am.,Vol.143,No.3,Pt.2,March2018 175thMeeting:AcousticalSocietyofAmerica 1769
ofuniformlayersdefinedbyanunknownnumberof(zeroormore)interfaces,sampledprobabilisticallywithtrans-dimensionalinver-
sion.(Zerointerfacescorrespondstoahalf-spacewithuniformparametervaluesequivalenttothoseatthebaseofthegradient.)The
inversionapproachiswellsuitedtoseabedenvironmentsconsistingofanupperlayerofsoft,fine-grainedsedimentsinwhichgeoacous-
ticpropertiesvaryasasmoothfunctionofdepthoverlyingaharder,layeredsubstrate,suchasattheONRSeabedCharacterization
ExperimentattheNewEnglandmudpatch.[ResearchfundedbytheOfficeofNavalResearch,OceanAcousticsProgram.]
8:20
2aAOa2. Geoacoustic inversion of the New England Mud Patch using modal time-frequency dispersion. Julien Bonnel (Appl.
OceanPhys.andEng.Dept.,WoodsHoleOceanographicInst.,266WoodsHoleRd.,MS#11,WoodsHole,MA02543-1050,jbonnel@
whoi.edu),DimitriosEleftherakis(LabSTICC,ENSTABretagne,Brest,France),StanE.Dosso,N.RossChapman(SchoolofEarthand
OceanSci.,Univ.ofVictoria,Victoria,BC,Canada),DavidR.Dall’Osto,andPeterH.Dahl(Appl.Phys.Lab.,Univ.ofWashington,
Seattle,WA)
Thispaperpresentsgeoacousticinversionofseverallow-frequencybroadbandsignalsrecordedduringtheSeabedCharacterization
Experiment(SBCEX)thattookplaceontheNewEnglandMudPatchinMarch2017.Theconsideredsourcesarechirpsemittedbya
towedJ15sourceandunderwaterimpulsescreatedbyMK64explosions.Thesesourcesarelow-frequency(f<250Hz)sothattheshal-
lowwaterenvironmentactsasadispersivewaveguide,andpropagationisconvenientlydescribedbymodaltheory.Thereceivedsignal
isrecordedonasinglehydrophoneplaced0.8moffthebottom.Inthiscontext,inversioniscarriedoutbymatchingmodaldispersion
curvesinthetime-frequencydomain.Experimentaldispersioncurvesareestimatedusinganon-linearsamplingschemecalledwarping.
Uptosixmodescanbeestimated,andnon-linearinversionresultsareconsistentwithwhatisknownaboutthearea.
8:40
2aAOa3.Inversionsfor sedimentparametersusinggeophoneandtetrahedral arraymeasurements inthe NewEnglandMud
Patch.GopuR.Potty,JamesHMiller(Dept.ofOceanEng.,Univ.ofRhodeIsland,115MiddletonBldg.,Narragansett,RI02882,
[email protected]),Ying-Tsong Lin, JulienBonnel, andArthur Newhall (Appl.OceanPhys.and Eng.,WoodsHole Oceanographic
Inst.,WoodsHole,MA)
MeasurementsofacousticpressureandparticlevelocityweremadeduringtheSeabedCharacterizationExperiment(SCEx)inthe
NewEnglandMudPatchsouthofCapeCodinabout70metersofwater.TheUniversityofRhodeIslandandWoodHoleOceano-
graphicInstitutiondeployedthe“geosled”withafour-elementgeophonearray,atetrahedralarrayoffourhydrophones,andseveral
hydrophonereceiveunits(SHRUs).Inaddition,anewlowfrequencysource,interfaceWaveSedimentProfiler(iWaSP)wasdeployed
toexciteinterfacewaves(Scholtewaves).TheiWaSPsystemconsistsofasourcetogeneratetheinterfacewaveandafour-elementac-
celerometerreceivearray.Resultsofinversionsforgeoacousticparameterswillbepresented.Arrivaltimedispersionfrombroadband
sources(SUSandCSS)andiWaSPwillbeusedfortheseinversions.Bothp-waveandScholtewavearrivalswillbeinvestigatedusing
thegeophoneandhydrophonedata.Seismicdatacollectedatthelocationwillbeusedtoconstrainthemodelparametersintheinver-
sion.Sedimentdatafromcores,otherin-situmeasurementsandinversionsusingothertypesofdatawillbeusedtocompareandvalidate
ourinversions.[WorksupportedbyOfficeofNavalResearch.]
9:00
2aAOa4.Attenuationinfine-grainedsedimentsforNewEnglandMudpatchin25–5000Hzband.DavidP.Knobles(KSA,LLC,
POBox27200,Austin,TX78755,[email protected]),PrestonS.Wilson(Mech.Eng.Dept.andAppl.Res.Labs.,TheUniv.of
TexasatAustin,Austin,TX),andWilliamS.Hodgkiss(UCSanDiego,LaJolla,CA)
Asubjectofconsiderableimportanceinlittoraloceanenvironmentsisthefrequencydependenceofsedimentattenuationforvarious
classesofsediments.Thewell-knownfrequencyexponentvalueof1.8forsandysedimentswasthesubjectofnumerousresearchstud-
ies.Formud-likeormixedsediments,forwhichthereisascarcityofexperimentaldata,valuesforthefrequencyexponentarenotwell
established.Previously,thesoundspeedstructureofasurfacemudlayerintheNewEnglandSeabedCharacterizationexperimentalarea
wasestimatedwithinversionandBayesianmethods.TheinversionsutilizedMK-64SUSexplosivesourcesina25-275Hzbandplaced
onconcentric circlesof2,4,and6.5kmradiiinthelatitude-longitudeplane.TheareawaspreviouslysurveyedwithCHIRPsonar
allowingformultiplesedimentlayerhorizonstobeconstrainedforlayerthicknessesbymeasuredtwo-waytraveltimes.Inthisanalysis,
alargerbandwidth(25-5000Hz)oftheSUS,theCombustiveSoundSource(CSS),andtonalsfromtowedsourcesatmultiplefrequen-
ciesallowforthedevelopmentofposteriorprobabilitydistributionsthatcontainthestatisticsofthefrequencydependenceofsediment
attenuationuptoabout5kHz.[WorksupportedbyONR]
9:20–9:35Break
1770 J.Acoust.Soc.Am.,Vol.143,No.3,Pt.2,March2018 175thMeeting:AcousticalSocietyofAmerica 1770
ContributedPapers
9:35 10:05
2aAOa5. Source characteristics and variability of impulsive sources 2aAOa7. Acoustics of biologically active marine sediments. Kevin M.
usedinoceanacousticsexperiments.MatthewC.Zeh,PrestonS.Wilson, Lee, Megan S. Ballard (Appl. Res. Labs., The Univ. of Texas at Austin,
AndrewR.McNeese(Mech.Eng.andAppl.Res.Labs.,TheUniv.ofTexas 10000 Burnet Rd., Austin, TX 78758, [email protected]), Gabriel R.
at Austin, 3374 Lake Austin Blvd., Apt. B, Austin, TX 78703, mzeh@ Venegas,andPrestonS.Wilson(Mech.Eng.Dept.andAppl.Res.Labs.,
utexas.edu),andDavidP.Knobles(KnoblesSci.andAnal.,LLC,Austin, TheUniv.ofTexasatAustin,Austin,TX)
TX)
Biological organisms are prevalent on and near the seabed; however,
Two types of impulsive sources were used extensively in the Seabed most predictive theoretical models do not explicitly address the acoustic
Characterization Experiment 2017 (SCE2017): Mk-64 Sound Underwater behaviorofbiologicallyactivemarinesediments.Sediment-acousticsmod-
Source(SUS),andtheCombustiveSoundSource(CSS).Bothofthesesour- els,suchasthosebasedonBiottheoryorgrain-shearingtheory,allowfor
cesrelyonthereleaseofchemicalenergyandhencetheradiatedacoustic parameterizationofvariousphysicalpropertiesincludingbulkdensity,po-
signalissubjecttovariabilityfromshottoshot.Inaddition,SUSactivates rosity,shearstrength,orporefluidviscosity,allofwhichcanbemodified
viaapressuresensorandthereisvariabilityinthedepthofactivation,which bythepresenceofbiologicalorganismsorbioturbation.Othermodelscan M
translatesintoadditionalvariabilityintheradiatedacousticsignal.Apairof include the effects gas bubble distributions, which can also be associated A
ship-deployed hydrophones was used during SCE2017 to record source with the presence of benthic biology, on compressional and shear wave E.
waveforms,andinthispresentation,variousacousticcharacteristicsofthese propagation.Inthispaper,weexaminesediment-acousticsmodelsincom- U
sources,suchassourcelevel,frequencycontent,andthenatureofthetime parison withdata from variousfield experiments focusedon infauna-and T
domain signals will be described in terms of their statistical variability. seagrass-bearingsediments.Themodelparametersarepartiallyconstrained a
2
[WorksupportedbyONR.] byphysicaldatafromcoresamplescollectedatthefieldexperimentsites.
Empiricalrelationsbetweenthecoredataparametersandacousticdatawill
9:50
alsobeexamined.[WorksupportedbyONRandARL:UTIR&D.]
2aAOa6.Distinctionsamongphysicaltypesofmarinesediments,espe-
10:20
ciallymud,andtheirpossiblefundamentals-basedandheuristicmodels.
AllanD.Pierce(CapeCodInst.forSci.andEng.,POBox339,399Quaker 2aAOa8.Implicationsfromaclay/siltsuspensionmodelofmudfordata
MeetingHouseRd.,EastSandwich,MA02537,[email protected]), from the Seabed Characterization Experiment. Elisabeth M. Brown
WilliamL.Siegmann,andElisabethM.Brown(MathematicalSci.,Rensse- (Mathematical Sci., Rensselaer Polytechnic Inst., Rensselaer Polytechnic
laerPolytechnicInst.,Troy,NY) Inst.,DeptMathematicalSci.,Troy,NY 12180,[email protected]),Allan
D. Pierce (Cape Cod Inst. for Sci. and Eng., East Sandwich, MA), Ying-
Marine sediments at differentlocationsand depths are not necessarily
TsongLin(Appl.OceanPhys.&Eng.,WoodsHoleOceanographicInst.,
similar.Distinctionsare(1)sandy/siltysediments,whenmostparticleshave
WoodsHole,MA),JasonD.Chaytor(CoastalandMarineSci.Ctr.,U.S.
settledandalmosteveryparticletouchesotherparticles,and(2)mudsedi-
GeologicalSurvey,WoodsHole,MA),andWilliamL.Siegmann(Mathe-
ments,wherethemajorityinalayeraresuspendedsothattheydonottouch
maticalSci.,RensselaerPolytechnicInst.,Troy,NY)
otherparticles.Mosttheoreticalandanalyticalmodelingovertheyearshas
largelybeenconfinedtosandy/siltysediments,andsomesuccessfulmodels, Mud-likemarinesedimentsmaybemodeledasasuspensionoffloccu-
althougharguablyheuristicandwithadjustableparameters,haveemerged. latedclayparticlesinwater,inwhichsiltparticlesareembeddedintheclay
Thereisalsosomespeculationthatsuchmodelsmightapplyequallywell flocs.Recentcalculationsbasedonthismodel[Pierceetal.,NewOrleans
formudsediments.Thepresentauthorsinrecentyearshaveconcentrated ASA] produced new predictions for the frequency-dependent phase speed
on the development of a fundamentals-based model for mud sediments, andattenuationofcompressionalwaves.Forphasespeed,verygoodcom-
althoughthereisasyetinsufficientdatatoadequatelytestitsvalidity.The parisonsbetweenmodelpredictionsandarchivaldatawerefound.Compari-
present paper speculates on what this model may have in common with sonswillbepresentedusinggeoacousticdatafromsedimentcoresextracted
modelsforsandy/siltysediments.ThereareexpectationsthattheMallock- fromtheNewEnglandMudPatch.Forattenuation,predictionsusingGaus-
Woodmodelmayapproximatelyapplyforsoundspeedpredictionsatvery siandistributionsofsiltparticleradiuswerecalculated.Anapproachwillbe
lowfrequencies.Argumentsarepresentedtotheeffectthatthephysicsis describedforproducingafrequency-dependenteffectiveparticleradiusto
sufficientlydifferentforthetwosedimentstypesthatasubstantiallydiffer- accountforsize-distributioneffectsusingsingle-particleattenuationexpres-
ent model is needed for mud sediments. One chief distinction is that the sions.Theinfluenceofnon-Gaussiansizedistributionsontheeffectivera-
solidportionofmudsedimentshasaportionthatisclayparticles,andthese diusandonthefrequencyintervalsofnear-linearattenuationbehaviorwill
havesubstantiallydifferentelectrolyticandcohesivepropertiesthanthose beshown.AnenvironmentalmodelforaWHOIAUVtrackdeployedinthe
ofquartzparticles. ONRSeabedCharacterizationExperimentwasconstructed,andinitialcom-
parisons were made between transmission loss calculations and acoustic
data.Benchmarkingwillbeperformedwithadditionalforwardcalculations,
alongwithestimatesofgeoacousticproperties.Particularinterestisinsedi-
mentattenuationanditsfrequencydependence.[WorksupportedbyONR.]
1771 J.Acoust.Soc.Am.,Vol.143,No.3,Pt.2,March2018 175thMeeting:AcousticalSocietyofAmerica 1771
TUESDAYMORNING,8MAY2018 GREENWAYA,11:00A.M.TO12:00NOON
Session2aAOb
AcousticalOceanography:AcousticalOceanographyPrizeLecture
JohnA.Colosi,Chair
DepartmentofOceanography,NavalPostgraduateSchool,833DyerRoad,Monterey,CA93943
Chair’sIntroduction—11:00
InvitedPaper
11:05
2aAOb1.Three-dimensionalshallowwatersoundpropagationandapplicationstowardacousticaloceanography.Ying-TsongLin
(Appl.OceanPhys.andEng.,WoodsHoleOceanographicInst.,Bigelow213,MS#11,WHOI,WoodsHole,MA02543,ytlin@whoi.
edu)
Underwatersoundpropagationinareasofthecontinentalshelf,shelfbreak,andcontinentalslopecanencounterstronghorizontal
reflection,refraction,diffraction,focusing,and/ordefocusingduetoavarietyofenvironmentalfactors,includingbathymetricvariabili-
ty,watercolumnfluctuations(internalwavesandshelf-breakfronts),andboundaryroughness.Theoretical,numerical,andexperimental
approacheshavebeentakentoinvestigatetheunderlyingphysicsofthesethree-dimensional(3-D)soundpropagationeffectsandtheir
temporalandspatialvariabilityinducedjointlybymarinegeologicalfeaturesanddynamicoceanographicprocesses.Somerecentwork
ontheoreticalanalysis,numericalmodelingandfieldworkexperimentstostudy3-Dsoundpropagationinnonlinearinternalwaveducts,
overthecontinentalslopeandinsubmarinecanyonswillbereviewedinthistalk.Theultimategoalofinvestingthese3-Dsoundpropa-
gationeffectsistoimprovelong-distanceacousticaloceanographictechnologyincomplexoceanenvironments.Anexampleusinga3-
Dback-propagationmethodforacousticinverseproblemswillbepresented,alongwithdiscussiononfeatureapplications.[Worksup-
portedbytheOfficeofNavalResearch.]
1772 J.Acoust.Soc.Am.,Vol.143,No.3,Pt.2,March2018 175thMeeting:AcousticalSocietyofAmerica 1772
TUESDAYMORNING,8MAY2018 GREENWAYF/G,8:00A.M.TO11:50A.M.
Session2aBA
BiomedicalAcoustics:UsingAcousticWavePropagationtoEstimateQuantitativeMaterial
PropertiesofTissueI
MatthewW.Urban,Chair
DepartmentofPhysiologyandBiomedicalEngineering,MayoClinicCollegeofMedicine,200FirstSt.SW,
Rochester,MN55905
Chair’sIntroduction—8:00
M
A
E.
InvitedPapers U
T
a
2
8:05
2aBA1.Magneticresonanceelastography:Statusofclinicalapplications.RichardL.Ehman(Dept.ofRadiology,MayoClinic,200,
Rochester,MN55905,[email protected])
Magneticresonanceelastography(MRE)isanimagingtechnologythathasbeenavailableasanFDA-clearedupgradetoMRIsys-
temssince2009.Worldwide,MREtechnologyhasbeeninstalledonapproximately1000MRIsystems.InOctober2017,theAMA
approvedthecreationofaCPTcodeforMRE.InMRE,propagatingshearwavesintherangeof30–300Hzaregeneratedintissue,and
imagedwithaphasecontrastMRItechnique.Thewaveimagesareprocessedwithaninversionalgorithmtogeneratecross-sectional
imagesquantitativelydepictingthecomplexshearmodulusoftissue.ThemainapplicationofMREiscurrentlyinnoninvasivediagnosis
ofchronicliverdisease.PublishedstudieshaveestablishedtheMREisthemostaccurateandtechnicallysuccessfulnon-invasivemodal-
ity for diagnosing liver fibrosis. Many other promising applications of MRE are being explored by investigators around the world,
includingassessmentofdiseasesofthebrain,heart,lung,andmuscleandtumorsofbreast,liver,prostate,liver,andotherorgans.The
newapplicationsthatclosestadoptioninclinicalpracticeare(1)assessmentofbraindiseaseand(2)advanceddiagnosisofliverdisease.
ThesenewapplicationsrequireacquisitionsequencesandprocessingalgorithmsthataremoreadvancedthanthecurrentproductMRE
techniques.
8:25
2aBA2.Magneticresonanceelastographyinversions:Technicalchallengesandrecentdevelopments.ArmandoManduca(Physiol.
andBiomedicalEng.,MayoClinic,Opus2-125,MayoClinic,2001stSt.SW,Rochester,MN55901,[email protected])
Magneticresonanceelastography(MRE)isaphasecontrastbasedMRIimagingtechniquethatcanquantitativelyandnon-invasively
measurefull3Dvectordisplacementdatafrompropagatingacousticwavesinvivo.Thedataacquiredallowthecalculationoflocalval-
uesofcomplexshearmodulusandthegenerationofimagesthatdepicttheviscoelasticpropertiesoftissue.Acquisitionsatdifferentfre-
quenciescancapturethedispersivebehaviorofthesequantities,andadvancedapproachesattempttomapanisotropicandporoelastic
properties of materials. We will discuss current approaches for the inversion of MRE data, focusing on the issues and assumptions
involved,andhighlightsomeofthechallengesfacedinsuchinversions,particularlyinthinorsmallstructuresinwhichwavepropaga-
tionisdominatedbywaveguideeffects.Wewillalsopresentresultsbasedonneuralnetworkinversions,whichmayhavelowerrepeat-
abilityerrorandbemoreresistanttonoisethansomecurrentapproaches.
8:45
2aBA3.Spectral-basedquantitativeultrasoundimaging:Amodelfreeapproach.MichaelL.Oelze,TrongNguyen,andMinhDo
(Dept.ofElec.andComput.Eng.,Univ.ofIllinoisatUrbana-Champaign,405NMathews,Urbana,IL61801,[email protected])
Quantitativeultrasound(QUS)imagingcanimprovethediagnosticcapabilitiesofultrasound.Spectral-basedQUSapproachesuti-
lizebackscatteredultrasoundsignalstoextractadditionalinformationabouttissuestate.Thesetechniquehavetraditionallyreliedon
scatteringmodelstodifferentiatetissuestate.However,theuseofmachinelearningapproachesmayobviatetheneedformodels.A
model-basedandmodel-free(principlecomponentanalysis(PCA))approachtospectral-basedQUSwerecomparedfortheirabilityto
differentiatefattyfromnon-fattyliverinarabbitmodel.PCAwasobservedtoprovidebetterdifferentiationoffattyfromnon-fattyliver,
i.e.,PCApredictedfattyliver86%ofthetimeversus36%formodel-based.Inaddition,threecalibrationapproachesforspectral-based
QUSwerecompared:thetraditionalreferencephantom,referencefree,andaninsitucalibrationtarget.Totestthecalibrationproce-
dures,aphantomwasscannedwithandwithoutalossylayerplacedontopandintegratedbackscattercoefficients(IBSCs)werecalcu-
lated from the scattered data. Utilizing an in situ calibration target provided the ability to account for transmission losses and
attenuation.TherootmeansquareerrorbetweenIBSCsestimatedfromthephantomwithandwithoutthelossylayerwere8.28forthe
referencephantomversus1.24fortheinsitucalibrationapproach.
1773 J.Acoust.Soc.Am.,Vol.143,No.3,Pt.2,March2018 175thMeeting:AcousticalSocietyofAmerica 1773