简介：

简介：

简介：Aunifiedtheoryforcalculatingthenoiseradiationofaninfiniteelasticplateexcitedbytheturbulentboundarylayerpressurefluctuationsispresented.Usingthewavenumberfrequencytransferfunctiontodes-cribethewholesystem,consistingoftheplateandtheliquidloading,ageneralexprossionofthecrossspectrumwasderiyed.Itisanintegralinthecomplexwavenumberplaneandleadstoasumoftheresiduesatthepolesoftwotypes.Onepoleintroducedbytheconvectiveridgeofthepressurefluctuationsyieldsadirecttransfercomponent,whichisanevanescentwaveinliquidbecausethepoleliesinthehighwavenumberregion.Theotherpolesintroducedbythetransferfunctionofstructureproducetheradiationfieldcomponentswiththeresonancemodesofaliq-uidloadedplate.ThepolepositionsandtheirresiduescanbecomputedapproximatelybyuseoftheResonanceScatteringTheory.Forthecaseofhydrodynamicnoise,wheretherangeofthefrequency-thicknessprod-uctofinterestisrelativelyl

简介：Theresearchisabouttheeffectofalayerofvaryingdensityofsea-bottomsedimentsonspatialcorrelationofsea-bottombackscattering.Therelationshipbetweenscatteringcrosssectionandspatialcorrelationisthatbackscatteringcrosssectiondecreasesquicklyandthespatialcorrelationbecomesstrongerastheincidentangleincreases.Therefore,thedensitydepthprofileisintroducedintosea-bottomhigh-frequencybackscatteringechomodel,whichisusedtosimulatesea-bottombackscatteringandcalculatethefunctionofspatialcorrelation.Theinfluenceofthedensitygradientonspatialcorrelationofsea-bottombackscatteringisinvestigatedbyanalyzingtherelationsbetweenverticalgradientofdensityandthescatteringcrosssection.Ascanbeseenfromthesimulationresults,theimpactofthedensitygradientonthespatialcorrelationisfoundmoresignificant.Whilethedensitygradientincreases,thescatteringcross-sectionandtheradiusofthespatialcorrelationbroaden,thespatialcorrelationbecomesstronger.Atthesametime,thescatteringcross-sectiondecreasesmorequicklyastheincidentangleincreases.

简介：

简介：

简介：