简介:Signalsarriveoutofphaseattheintendedreceiverfromcollaborativebeamforming(CB)nodesduetotheinstabilityintheoutputfrequencysignalsoftheuniversalsoftwareradioperipheral’s(USRP)localoscillator(LO).Thesenodesincludingthetargetmustsynchronizetheiroscillatorfrequenciesforcoherentsignalreception.Inordertodothis,frequenciesandphasesofthesignalsshouldbeestimatedinsoftwaredefinedradio(SDR)andsmoothenwithnonlinearfilterssuchastheextendedKalmanfilter(EKF).TheprocessnoiseparametersoftheNIUSRP-2920nodeswillhavetobecalculatedandusedwiththeEKFprocessnoisecovariancematrix.Thesenodesaregreencommunicationhardwaredeviceswheremostofthehardwareunitsarenowsoftwaredefined.ThisarticleusesthedirectspectrummethodtoobtainthephasenoisevaluesatvariousfrequencyoffsetsoftheNIUSRP-2920inordertocalculatethepowerspectraldensityoffractionalfrequencyfluctuation.Byapplyingthepower-lawnoisemodeltothisobtainedvalue,thegeneratedwhitefrequencynoiseandrandomwalkfrequencynoisevaluesareq1=1.93×10-21andq2=5.86×10-18,respectively.
简介:Thispaperdealswithinternallygeneratednoiseofbioelectricamplifiersthatareusuallyusedforprocessingofbioelectricevents.Themainpurposeofthispaperistopresentaprocedureforanalysisoftheeffectsofinternalnoisegeneratedbytheactivecircuitsandtoevaluatetheoutputnoiseoftheauthor'snewdesignedbioelectricamplifierthatcausedbyinternaleffectstotheamplifiercircuititselfinordertocompareitwiththenoisegeneratedbyconventionalamplifiers.Theobtainedanalysisresultsofinternallygeneratednoiseshowedthatthetotaloutputnoiseofbioelectricactivecircuitsdoesnotincreasewhensomeoftheirresistorshavealargervalue.Thisbehavioriscausedbythedifferenttransferfunctionsforthesignalandtherespectivenoisesourcesassociatedwiththeseresistors.Moreover,thenewdesignedbioelectricamplifierhasanoutputnoiselessthanthatforconventionalamplifiers.Theobtainedanalysisresultswerealsoexperimentallyverifiedandthefinalconclusionsweredrawn.
简介:Byusingthemodernlydevelopedtechniquesofpossibilityandset-valuedstatistics,thispaperdeter-minedthethresholdsofvariouscategoriesofnoiseannoyanceanddefinedthedose-responserelationbe-tweenthelevelsofnoiseandtheirannoyance.Threefactorscontrolledintheexperimentweretypesofnoise:impulseandtraffic;levelofnoise:5Leqfrom45—85dB(A);andperformancetask:withandwithoutspeechrecognition.NoiseinterferencewithspeechrecognitionwasmeasuredwiththeSDTmethod.Ourex-perimentalresultsshowedthatLeqofimpulsenoiseshouldbehigherthanthatoftrafficnoisetogetequalannoyance;thespeechrecognitiontaskmightlightentheexperienceofannoyance;thehigherthelevelofnoise,themoreitsinterferencewiththespeechrecognition,thatis,thelessthevalueofd′.
简介:J.StuartBolton,ed.xx+636pp,NoiseControlFoundationP.O.Box2469,ArlingtonBranch,Poughkeepsie,NY12603,U.S.A.PriceUS$60.00+19.00airmail.TheNOISE-CON88conferenceofU.S.A.washeldatPurdueUniversity,june20—22,1988.Thethemeoftheconferenceis"NoiseControlDe-sign—MethodsandPractice".Theproceedingscontainthreedistinguishedlecturesand100contributedpapers.Thethreedistinguishedlecturesalladdressthethemeoftheconference.Inhislecture“Istherea‘zero-option‘innoisecontroldesign?”ProfessorP.E.DoakoftheInstituteofSoundandVibrationResearch,SouthamptonUniversity,dis-cussesthepotentialforachievingcompletenoisecancellationandhowitmightbeachievedinpractice.Inthelecture"LoudnessPattern(ISO532B),anexcellantguidetonoise-induceddesignsandtoexpectedpublicreactions"presentedbyProfessor
简介:这份报纸在其解决方案polynomially至多成长的切换的政体下面考虑一个给定的中立功能的系统。系统能容忍如果系统服从于另一环境噪音,保存多项式生长的Brownian噪音和颜色噪音吗?答案是积极的。这份报纸一起显示那环境噪音和政体切换工作让其答案polynomially至多成长的原来的中立微分系统成为答案的一个新中立功能的微分系统将仍然保存多项式生长。这显示这个中立功能的微分系统能容忍没有失去多项式生长的性质的小噪音,它暗示坚韧性。这份报纸也证明标准对作为功能的系统的一种特殊情况的中立延期系统合适。最后,二个例子被给说明主要理论。
简介:Inthisarticle,anewacoustictesttechniqueusingtowedmodelwasintroducedtostudyflownoisecausedbyasurfaceship.Theprojectofmodeltestwasbeproperlydesignedforacousticsignalcollectingandwiththehelpofappropriatedataprocessingmethoddifferentkindsofacousticsourcescouldbesuccessfullyidentified.Alotofworkaboutfuidnoisecouldbecarriedonwiththetowedmodel,andthenoisecorrespondingtolowfrequencywhichisespeciallyinterestedforitslongdistanceradiatingwithsmallattenuationcouldalsobestudiedinthisway.
简介:我们由使用nonstationary多项式试穿(NPF)为地震噪音变细建议一个新奇方法,它能沿着事件与振幅变化估计协调部件。有变化时间的系数的NPF能适应地估计协调部件。多项式系数的光滑被塑造规则化控制。信号沿着在一个普通中点(CMP)的偏移量轴是协调的在正常moveout(NMO)以后的集合。我们使用NPF估计有效信号并且从而稀释随机的噪音。为象地面转动那样的光线的像事件的噪音,我们首先采用光线的踪迹(RT)转变数据到时间速度域的变换。然后,NPF被用来在RT领域估计协调噪音。最后,协调噪音适应地从吵闹的数据集被减去。建议方法能有效地沿着事件与振幅变化估计协调噪音,没有需要建议那个噪音振幅是不变的。结果合成并且域数据例子证明与象静止多项式适合和低切割过滤器那样的常规方法相比,建议方法能有效地压制地震噪音并且保存信号。
简介:Fromtheevolutionaryvectordeacriptionofslowlysime-varyingnoiseprocess,ameasurefornon-stationarityisdeveloped.Itincludesboththenon-stationaritiesofpowerandofspectrumshape.Asasingleparameter,itisacomparablequantityfordifferentprocesses.Applicationtotheanalysisofprecisegearboxisprescnted.
简介:Thefar-fieldnoiseradiatedfrommixinglayersisdeterminedbythenear-fieldflowdynamicswhichissensitivetotheinitialperturbationofinstabilityintroducedphysicallyornumerically.Thisstudyfocusesontheeffectsofthephasedelayintwoinitialperturbations,oneatthefundamentalwavenumberandtheotheratitssubharmonicbothcalculatedfromlinearinstabilityanalysis,onthesoundgenerationinmixinglayers.Whendifferentphasedelaysφ_1changingfromzeroto2πisappliedonthefundamentalmode,weobservedifferentvortexmergingprocesses(e.g.vortexpairingortearing).Thestrongnonlinearinteractioninthemergingprocessgeneratesmostofthenoisefrommixinglayers.Thereshowsapatterninaperiodof2πfortheresponseoffar-fieldsoundtothechangeofφ_1.Similareffectsonthedynamicsandacousticscanbeachievedbyaddingdifferentphasedelaysφ_2tothesubharmonicmodeinstead,however,theresponserepeatsinaperiodofonlyπforφ_2.Theeffectsofthecombinationofdifferentphasedelaystootherparameters,includingtheamplitudeandwavenumberforeachperturbations,arealsoinvestigated.Alltheresultsindicateacriticalroleofnonlinearityinthesoundgenerationmechanismofmixinglayers.
简介:机器学习者的精确性被数据的质量影响学习者上被劝诱。在这篇论文,训练数据集的质量被移开划分过滤器作为吵闹检测的例子改进。合适的数据集首先被分成子集,;不同基础学习者在每这些裂口上被劝诱。如果它被某些基础学习者分类,预言以如此的一个方法被联合,一个例子作为吵闹被识别。划分过滤器的二个版本被使用:多重划分的过滤器;反复划分的过滤器。过滤器移开的例子的数字被过滤器的投票的计划调节;重复的数字。这研究的主要目的是比较造在上的最后模型的预兆的表演过滤;未过滤的训练数据集。一个高保证软件项目的软件测量数据的案例研究被执行。模型的预兆的表演在过滤合适的数据集上造了,这被显示出;在吵闹的测试数据集上评估了通常比造在上的那些好吵闹(未过滤)合适的数据集。然而,预兆的性能被噪音的存在在评估数据集基于某些好攻击的过滤器影响。
简介:Basedonthewhiteningpropertyofwavelettransformationfor1/fnoise,thispaperaddressestheproblemofdetectingdeterministicsignalsinthepresenceof1/ffractalnoise.Thetransferfunctionofwhiteningfilterisprovidedaswellastheconditionforwhitening.ThereceiverstructurebasedonKarhunen-Loeveexpansionandthedecisionrulearealsogiven.Finallyperformanceofthedetectorisanalyzed.
简介:ThedatarecordedduringthesitesurveyintheZhangzhouareainFujianProvincebetweenOctober23,2007andDecember3,2007wasanalyzed.Themainmethodsadoptedforthenoiselevelofthisareaarethenoiserootmeansquare(RMS),noisepowerspectrumdensityandnoisecoherencyfunction.Theresultsindicatethatthenoiselevelsofthesurveysitesarehigherinthe1s-10speriods,whichisthemainfrequencybandofpreliminarymicroseism,andalso,twomainnoisesourceswerefoundin1.5Hzandaround5Hz.Accordingtoarithmetic,thedirectionandfrequencybandofthenoisesourcewereanalyzedandacademicproofswerepresented.Atlast,wefoundthatthenoisesourcein1.5Hzwasmadebythewaterwavearousedbythewindinthereservoirregionandthenoisesourcearound5Hzwasmadebythepowerstationinthenortheastdirection