简介:Aneasyandpracticalsystemoffeeblefluctuationofliquidelectricalconductivityisdescribed.Thesystem,whichincreasesaprecisiononthethreeordersmagnitudeascomparedwiththatoftherecentdomesticconductivitymeter,isusedtomeasurethefeeblefluctuationoftheconductivitybymeansofcompensationandcomparison,sothatitsolves,theproblemofmeasuringthefeeblefluctuation.
简介:FluctuationofExcitationFunctionsinDissipativeHeavyionCollisions¥XuHushan;WangQi;LuJun;LiSonglin;ZhuYongtai;YinXu;FanE...
简介:Transmissionsignalofradiationinsuspensionofparticlesperformedwithahighspatialandtemporalresolutionshowssignificantfluctuations,whicharerelatedtothephysicalpropertiesoftheparticlesandtheprocessofspatialandtemporalaveraging.Exploitingthisconnection,itispossibletocalculatetheparticiesizedistribution(PSD)andparticleconcentration.Thispaperprovidesanapproachoftransmissionfluctuationspectrometry(TFS)withvariablespatialaveraging.Thetransmissionfluctuationsareexpressedintermsoftheexpectancyoftransmissionsquare(ETS)andareobtainedasaspectrum,whichisafunctionofthevariablebeamdiameter.Thereversalpointandthedepthofthespectrumcontaintheinformationofparticlesizeandparticleconcentration,respectively.
简介:Naturalandventilatedcavitationsgeneratedonasmooth-nosedaxisymmetricbodywerestudiedexperimental-ly.Thecharacteristicsofsmallscaleandlocalizedfluctuationsof'steadycavities'weremeasuredbypressuretransducers.Comparisonsbetweennaturalandventilatedcavitiesatdiffer-entmeasuredpointsforseveralcavitationnumbersweredone.Itwasobservedthatthedominantfluctuationswereconcen-tratedinthefrequencyrangeofOHz-50Hzforallthecavitati-oncases,Similarshapesandmagnitudesofthefrequencyspectraweredetectedforbothnaturalandventilatedcavities.Muchlargerspectralamplitudeinthecavityclosureregionsuggestedasfluctuationssource.Frompartialcavitatingflowtosupercavitatingflow,thedominatfrequencyandthecorre-spondingamplitudedecreasedwithdecrasingcavitationnum-ber,whichmeantthatcavitybecamemoresteadywhiledevel-oping.
简介:FluctuationofExcitationFunctionsofDampedProductsofIdentifiedIsotopes¥WangQi;LuJun;XuHushan;LiSonglin;ZhuYongtai;YinX...
简介:AdetailedstudyofthepressureoscillationinducedbythefilmboilingofHeⅡispresented.Thefilmboilingstateandthestabilitynofthevapourfilmaredeterminedbythegoverningparameter(i.e.theimmersiondepth).Itisfoundthatthepowerdensityspectrumofthepressureoscillationinducedbythefilmboilingdisplaysthe1/f^α-behaviour.Theexponentαwasfoundtobewithintherangefromonetotwo,whichindicatestheexistenceofself-organizedcriticalityinthefilmboilingofHeⅡ.
简介:CHAOTICOUTPUTOFSSTFLUCTUATIONSTOCHASTICMODELWITHGIVENPARAMETERS¥YanShaojinandPengYongqing严绍瑾,彭永清(NanjingInstituteofMeteorolog...
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简介:Theobservedlossrateofbothparticlesandenergyfromhotconfinedtoroidalplasmasismuchhigherthantheonepredictedbyneoclassicaltransporttheory,whichdependsuponmeanplasmaparametersandCoulombcollisions.Manytypesofplasmaturbulencehavebeenproposedtoexplainanomalousplasmatransport.Thefluctuationofplasmaparametersaroundtheirmeanvaluescancausetransportthroughelectrostaticormagneticfluctuations.Thefluctuationdrivenradialparticlefluxisgivenby
简介:Abstract:Hydrologicalregimesinfluenceecologicalpatternsandprocessesaswellasalterratesofwetlandevapotranspiration.ThisstudyaimedtoinvestigatetheimpactofgroundwaterfluctuationonevapotranspirationofPhragmitesaustralis.SupportedbyfielddataobtainedfromtheBaiyangdianLakeinnorthernChina,thevariationsingroundwaterlevelswereexplored,andthechangesinsoilwaterandevapotranspirationofreedwereanalyzedtoinvestigatedifferentgroundwaterlevelscenariosusingHYDRUS-1Dmodel.Theresultsshowedthatsoilwatercontent,rechargedbygroundwater,remainedstableinthelowersoillayerbutvariedstronglyintheupperlayerofthesoilprofile;incomparisontoevaporation,Phragmitesaustralistranspirationcontributedsignificantlymoretotheoverallevapotranspirationrate;thehighlevelsofevapotranspirationcouldbemaintainedwhengroundwaterlevelsvarybetween1.0mand1.8m,whileitwasreducedwithanincreaseingroundwaterlevelsasaresultofwaterstressconditions.TheresultsalsoindicatedthattheevapotranspirationofPhragmitesaustraliscouldmaintainhigherevapotranspirationratesundernaturalwaterlevels.Theevapotranspiration,inotherwords,mightbethemainwaterconsumer,butitneverthelesshaslittleeffectonwaterlevelsduringwatershortages.TheevapotranspirationofPhragmitesaustralisrespondedtothechangesingroundwaterlevelscouldhelpresearchersunderstandwaterrequirementsofthewetlandsandestablishsuitablewaterlevelsforthewetlands.
简介:Detrendedfluctuationanalysis(DFA)isfitforstudiesonthelong-rangeexponentialcorrelationofnon-stationarytimeserial.Inthispaper,inordertofindahypoxiaadaptabilityevaluationcriterion,theheartrateandSaO2signalsareanalyzedbythismethod.Thedemarcateexponentaboutfit-good-groupandfit-bad-groupinhypoxiaandnormalairarecalculatedandcompared.Theresultshowsαisdifferentindifferentsituation,theαinhypoxiaismuchhigherthanαofbreathinnormalair.Andαoffit-good-groupishigherthanfit-bad-group.ItshowsthatDFAcouldbeagoodcriteriontoanalyzehypoxiaadaptability,whichisusefulintheanalysisofhypoxiaphysiologysignal.
简介:AIM:Tosystematicallyreviewwhethertheincreasedfluctuationofintraocularpressure(IOP)isariskfactorforopenangleglaucoma(OAG)progression.METHODS:ScientificstudiesrelevanttoIOPfluctuationandglaucomaprogressionwereretrievedfromMEDLINE,EMBASEandCENTRALdatabases,andwerelistedasreferencesinthispaper.Thehazardratio(HR)wascalculatedbyusingfixedorrandom-effectsmodelsaccordingtotheheterogeneityofincludedstudies.RESULTS:Individualdatafor2211eyesof2637OAGpatientsinfourteenprospectivestudieswereincludedinthisMeta-analysis.Allstudieswerelongitudinalclinicalstudieswithfollow-upperiodrangingfrom3to8.5y.ThecombinedHRwas1.23(95%CI1.04-1.46,P=0.02)fortheassociationbetweenIOPfluctuationandglaucomaonsetorprogressionwiththeevidenceofheterogeneity(P<0.1).SubgroupanalyseswithdifferenttypesofIOPfluctuationwerealsoevaluated.ResultsindicatedthatthesummaryHRwas0.98(95%CI0.78-1.24)inshort-termIOPfluctuationgroup,whichshowednostatisticalsignificancewithheterogeneity,whereas,thecombinedHRwas1.43(95%CI1.13-1.82,P=0.003)inlong-termIOPfluctuationgroupwithouthomogeneity.SensitivityanalysisfurthershowedthatthepooledHRwas1.10(95%CI1.03-1.18,P=0.004)forlong-termIOPfluctuationandvisualfunctionprogressionwithhomogeneityamongstudies(P=0.3).CONCLUSION:Long-termIOPfluctuationcanbeariskfactorforglaucomaprogressionbasedonthepresentedevidence.Thus,controllingtheswingofIOPiscrucialforglaucomaorglaucomasuspectingpatients.
简介:ComplexsystemsconsistingofNagentscanbeinvestigatedfromtheaspectofprincipalfluctuationmodesofagents.Fromthecorrelationsbetweenagents,anN×NcorrelationmatrixCcanbeobtained.TheprincipalfluctuationmodesaredefinedbytheeigenvectorsofC.Nearthecriticalpointofacomplexsystem,weanticipatethattheprincipalfluctuationmodeshavethecriticalbehaviorssimilartothatofthesusceptibity.WiththeIsingmodelonatwo-dimensionalsquarelatticeasanexample,thecriticalbehaviorsofprincipalfluctuationmodeshavebeenstudied.Theeigenvaluesofthefirst9principalfluctuationmodeshavebeeninvesitigated.OurMonteCarlodatademonstratethattheseeigenvaluesofthesystemwithsizeLandthereducedtemperaturetfollowafinite-sizescalingformλn(L,t)=Lγ/νfn(tL~(1/ν)),whereγiscriticalexponentofsusceptibilityandνisthecriticalexponentofthecorrelationlength.Usingeigenvaluesλ1,λ2andλ6,wegetthefinite-sizescalingformofthesecondmomentcorrelationlengthξ(L,t)=Lξ(tL~(1/ν)).Itisshownthatthesecondmomentcorrelationlengthinthetwo-dimensionalsquarelatticeisanisotropic.