简介：CallaghanandWhite(2009)putforwardtheautomatedwhitecapextraction(AWE)techniquetodeterminethewhitecapcoverage(W).AnimprovedAWEwasusedtoanalyzeimagescollectedintheSouthChinaSeaduring2012and2013andinwesternPacificduring2015todetermineW.Theinfluencesofmeteorologicalandoceanographicfactorsonwhitecapcoveragewereinvestigatedinthisstudy.ItisfoundthatWincreaseswithwindspeed.ScalefactorandexponentofparameterizationforW(U10)varygreatlyindifferentmodels.Overall,thereisalargerscatterofWatlowwindspeedthanathighwindspeed.Wdecreaseswiththeincreasingofwaveage.Comparedwithwindspeed,thescatterofWissmallerwithwaveage,whichmeanstheimpactofwaveageonthewhitecapcoverageismorerobustundervariousenvironmentalconditions.ThereisnosignificantdependenceonSSTandwhitecapcoverageseemstoweaklydecreasewithSST.Wdecreaseswiththeatmosphericstability.RelationshipbetweenWandwindspeedchangewhenswellsaredominant.SwellcansuppresswavebreakinganddecreaseW.Theeffectisindependentofthedeflectionanglebetweenwindwaveandswell.

简介：嗨,朋友,想和我一起去吃"HighTea"吗?什么?"高茶"?这是什么意思?意思是茶被放在很高的桌子上吗?哈哈,不是的。它和"下午茶"的意思十分相近。我只是想和你去吃些点心!

简介：Thispaperpresentsananalysisofthepotentialforenginespeedreductioninhydraulicequipment,takingintoaccountnotonlytheminimumenginespeedrequiredtomeetthecurrentflowdemand,butalsotheminimumspeedcapableofacceleratingtheenginetomeetincreasedflowdemandinthenearfuture.Thisisapredictivetask,asitrequiresanestimateoftheoperator'sintentiontoincreaseflowdemand.Wepresentananalysisofthepotentialforenginespeedreductionusingaworkcyclefroma40tonexcavatorloadingatruck,whichresultsinapotential33%reductioninthemeanenginespeedwithnoreductioninusefulworkrate.Wealsopresenttwonewenginespeedcontrolalgorithmstoperformthispredictivetask.

简介：Coherentstructuresareessentialforthemomentumexchangeandturbulenceproductioninwall-boundedturbulentflows.Diversifiedcoherentstructureshavebeenobservedinturbulentboundarylayers,andhairpin-basedvorticesdominatemostoftherelevantliterature.However,thereisnoconsensusyetontheoriginandformingmechanismofhairpinvortices.Herein,fivecornerstonespertainingtotheframeworkofhairpin-basedcoherentstructuresarereviewed,andthreedifferenthairpingenerationmechanismsareclarified.Next,thetime-resolvedtomographicparticleimagevelocimetry(Tomo-PIV)isusedinanearlyturbulentboundarylayer(Reθ=420)toinvestigatetheoriginofhairpinvortices.Thetimelinesrevealatriangularbulgeinthelow-speedstreak(LSS),andtheinitialroll-upoccursattwosidesofit.Meanwhile,thematerialsurfacesmanifestasathree-dimensional(3D)wavestructureintheLSS,whichmaysupportthemodelofasoliton-likecoherentstructure(SCS).Subsequently,themethodofLagrangian-averagedvorticitydeviationisusedtodetectearlyvortices.Wefindthatthe3Dwavestructureisflankedbytwovortices,thusconfirmingtheroll-upoftimelinesanddemonstratingtheadvantageoftheLagrangiancriteriaincapturingstructuresincomplexflows.Theseresultssuggestthatvariouscoherentstructuresmayevolvefromthemetamorphosisof3Dwavestructuresandtheirlaterinteraction.Finally,thelimitationsoftraditionalexperimentalandpost-processingtoolsarediscussed.

简介：Mathergavethenecessaryandsufficientconditionsforthefinitedeterminacys-moothfunctiongermswithnomorethancodimension4.Thetheoremisveryeffectiveondetermininglowcodimensionsmoothfunctiongerms.Inthispaper,theconceptofrightequivalentforsmoothfunctiongermsringgeneratedbytwoidealsfinitelyisdefined.Thecontainmentrelationshipsoffunctiongermsstillsatisfyfinitek-determinacyundersufficientlysmalldisturbancewhicharediscussedinorbittangentspaces.Furthermore,themethodsinjudgingtherightequivalencyofArnoldfunctionfamilywithcodimension5arepresented.

简介：intheteachingofreadingteachersoftendojustthat.Ratherthanletthestudentsinto,themostimportanttechniqueateachercanusetoguidestudentstowardgrammaticallycorrectwritingistoletthemwrite,alotsofprobelmsstillexsitintheEnglishteachingespeciallyintheteachingofreadingandwriting.Inthispaper

简介：Permanentmagnetscapableofreliablyoperatingathightemperaturesupto450?Carerequiredinadvancedpowersystemsforfutureaircrafts,vehicles,andships.ThoseoperatingtemperaturesarefarbeyondthecapabilityofNd–Fe–Bmagnets.PossessinghighCurietemperature,Sm–Cobasedmagnetsarestillveryimportantbecauseoftheirhightemperaturecapability,excellentthermalstability,andbettercorrosionresistance.Theextensiveresearchperformedaroundtheyear2000resultedinanewclassofSm2(Co,Fe,Cu,Zr)17-typemagnetscapableofoperatingathightemperaturesupto550?C.ThispapergivesasystematicreviewofthedevelopmentofSm–Copermanentmagnets,fromthecrystalstructuresandphasediagramstotheintrinsicmagneticproperties.AnemphasisisplacedonSm2(Co,Fe,Cu,Zr)17-typemagnetsforoperationattemperaturesfrom300?Cto550?C.Thethermalstabilityissues,includinginstantaneoustemperaturecoefficientsofmagneticproperties,arediscussedindetail.Thesignificanceofnanograinstructure,nanocrystalline,andnanocompositeSm–Comagnetmaterials,andprospectsoffuturerare-earthpermanentmagnetsarealsogiven.

简介：Alaskapollockisanimportantproteinsourcewhichisextensivelyusedinthefoodindustry.Pollockproteinisolates(PPI)withsignificantlyenrichedproteincontentscouldbepreparedusingisoelectricsolubilization/precipitation(ISP)processing;however,thefunctionalpropertiesofthisprocessislimitedbythelargeamountofwater-insolubleproteins.Inthisstudy,weinvestigatedtheinfluenceofhighhydrostaticpressure(HHP)treatmentonthesolubilityandstructuralchangesofPPI.PPIobtainedusingISPistreatedwithhydrostaticpressuresof200,300,400,and500MPaforupto15min,andtheHHP-treatedsampleswereobservedtoexhibitsignificantlyimprovedsolubilities.FurtherbiochemicalassaysrevealthatthecontinuousHHPtreatmentsreducethecontentsoffreesulfhydrylgroupsandpromotetheformationofmacromoleculeswithbetterwatersolubilities,whichmayinducethesolubilityimprovementsoftheHHP-treatedPPI.OurresultsindicatethatHHPcanbeutilizedtoeffectivelypreparehighlywater-solubleAlaskapollockproteininfoodprocessing.

简介：Weexperimentallydemonstratetwokindsofallfew-modefiber(FMF)ringlaserswithhigh-ordermode(HOM)oscillationinthelasercavity.Onekindisaswitchable-wavelengthall-FMFHOMlaserwithanoutputoftunableopticalvortexbeams(OVBs);theotherisaQ-switchedall-FMFHOMlaserwithanoutputofpulsedcylindricalvectorbeams(CVBs).Thelasersarecomposedofall-FMFcomponentsandfew-modeerbium-dopedfiber.ASagnacinterferometermadeofa3dBFMFcouplerfunctionsasthewavelengthselector,andswitchablemultiwavelengthtunableOVBsareexperimentallyrealized.Carbonnanotube-basedsaturableabsorbersandthenonlinearpolarizationrotationtechniqueareusedtoachieveQ-switchedCVBlasers.Thisisthefirstreport,toourknowledge,onthegenerationofswitchable-wavelengthandQ-switchedHOMbeamsinall-FMFlasercavities.

简介：Inthisresearch,thevibrationofelevatorropes,includingthemainropeandcompensationropeareinvestigatedsimultaneouslyinahigh-riseelevatorsystemunderearthquakeexcitation.Moreover,thepaperpresentsanewcontrolmethodtorestraintheswayofbothropes.Thisstudyconsidersvaryingropelengthsduringelevatoroperationwhichcauseothersystemparameterssuchasnaturalfrequency,anddampingratiotobetime-variantvariables.Thedynamicsoftheropesareanalyzedbysolvingthegoverningnon-stationary,nonlinearequationnumerically.Inordertomitigatethevibrationofropesinseveralmotionconditions,particularlyupwardsmovement,downwardmovement,stoppedatthelowestposition,andstoppedatthehighestposition,anactiveequipmentisinstalledatthecompensationsheave.Thestabilityofthesystemusingthecontrollerisanalyzedatfourstates:withoutdisturbanceandstaticcar,withoutdisturbanceandmobilecar,includingdisturbanceandstaticcar,andincludingdisturbanceandmobilecar.Theefficiencyofthecontrollerusedfordampeningthevibrationofelevatorropesisvalidatedbynumericalsimulationresults.

简介：Anenergyapproachisproposedtodescribetheelectromigrationinducedgrainrotationunderhighcurrentdensity.Thedrivingforceisassumedtoarisefromthegrain-boundaryenergyreductionandincreaseoftheinnerenergyfromthejouleheating.Energydissipatesbythegrainboundarydiffusionunderelectromigrationandviscousboundaryslidingisconsidered.Basedontheconservationofenergyproductionanddissipation,anequilibriumequationisdevelopedtopredictthegrainrotationrateanalytically.Itisrecognizedthatthegrainrotateswiththereducingofelectricalresistivityandinverselyproportionaltothegrainlength.Thetheoreticalpredictioniscomparedwiththeexperimentaldata,whichshowsgoodaccuracyontherotationtrendandthespecificrotationrate.

简介：Becauseoftheexcellentmechanicalpropertiesof34C「NiMo6steel,itiswidelyusedinhigh-valuecomponents.Manyconventionalapproachestostrengthening-steelstypicallyinvolvethelossofusefulductility.Inthisstudy,34CrNiMo6Steelhavinghighstrengthandductilityisproducedbylasersolidforming(LSF)w让haquenching-tempering(QT)treatment.TemperingofbainiteismainlybysolidphasetransformationinthepreviousLSFlayersduringtheLSFprocess.ThestablemicrostructureofLSFconsistsofferriteandfinecarbides.Themicrostructuretransferstotemperedsorbiteafterheat-treatment.ThetensilepropertiesoftheLSFsteelmeetthoseofthewroughtstandard.TheUTSandelongationofLSFsampleat858MPa,19.2%,respectively,aregreaterthanthoseofthewrought.TheQTtreatmentenhancedtheultimatetensilestrengthandyieldstrengthoftheLSFsample.Theultimatetensilestrength,yieldstrength,reductioninarea,andelongationoftheLSF+QTsampleat980MPa,916MPa,58.9%,and13.9%,respectively,aregreaterthanthoseofthewroughtstandard.TheyieldstrengthoftheLSF+QTsampleisapproximately1.27timesthatofthewrought.TheLSFsamplesfailedinaductilefracturemode,whiletheLSF+QTsamplesshowedmixed-modefailure.ThedefectshaveonlyasmalleffectonthetensilepropertiesowingtotheexcellentductilityoftheLSFsample.

简介：Wereportonadiode-end-pumpedhigh-powerandhigh-energyNd:YAGsingle-crystalfiberlaserat1834nm.Two808nmdiodesinjectingabout58WpumppowerintotheNd:YAGfiberhavegenerated3.28Wcontinuouswaveand1.66WCr:ZnSe-basedpassivelyQ-switchedlasers.Slopeefficiencieswithrespecttopumppowersare8.7%forthecontinuous-wavelaserand4.9%fortheQ-switchedlaser.Theextractedmaximumpulseenergyisabout266.9μJ,andthecorrespondingmaximumpulsepeakpoweris2.54kW.Theseperformancesgreatlysurpasspreviousresultsregardingthisspecificlaseremissionbecausethelasergainmediumintheformoffibercansignificantlymitigatethermallyinducedpowersaturationthankstoitssignificantlyreducedthermallensingeffect.Single-crystalfiberlasersshowgreatpotentialforhighaveragepower,pulseenergy,andpeakpower.

简介：Developingalow-cost,room-temperatureoperatedandcomplementarymetal-oxide-semiconductor(CMOS)compatiblevisible-blindshort-wavelengthinfrared(SWIR)siliconphotodetectorisofinterestforsecurity,telecommunications,andenvironmentalsensing.Here,wepresentasilver-supersaturatedsilicon(Si:Ag)-basedphotodetectorthatexhibitsavisible-blindandhighlyenhancedsub-bandgapphotoresponse.Thevisible-blindresponseiscausedbythestrongsurface-recombination-inducedquenchingofchargecollectionforshort-wavelengthexcitation,andtheenhancedsub-bandgapresponseisattributedtothedeep-levelelectrontraps-inducedband-bendingandtwo-stagecarrierexcitation.TheresponsivityoftheSi:Agphotodetectorreaches504mA·W-1at1310nmand65mA·W-1at1550nmunder-3Vbias,whichstandsonthestageasthehighestlevelinthehyperdopedsilicondevicespreviouslyreported.Thehighperformanceandmechanismunderstandingclearlydemonstratethatthehyperdopedsiliconshowsgreatpotentialforuseinopticalinterconnectandpower-monitoringapplications.

简介：Achievingnotonlyhighmechanicalstrengthsbutalsohighductilityisrecentlyestablishedusinganadditivemanufacturingtechniquecalledselectivelasermelting.Inthepresentstudy,stainlesssteel304Lfullydensesamplesweresuccessfullyprintedusingthe3Dsystems-ProX300printingmachine.TheductilityandtensileyieldstrengthwerealmosttwoandthreetimeshighercomparedtothoseofASTMcast'salloy.Honeycomblikenano-cellularstructurew让hdifferentorientationwasobservedinthefinegrains(-4μm)duetofastcoolingrate.Inadd让ion,theformationofmartensitephaseinrandomgrainsisalsoacontributortothestrengths.Furthermore,negativeresidualstressesinthebuildandhorizonraldirectionsweredetectedandassistedfurtherincreaseinthetensilestrength.Fractographyrevealedtheductilefeatureofplasticdeformationandthecrackopeningsatunmeltedparticlesorpores.

简介：Inthefieldofmedicalimaging,thetraditionallocalbinarypattern(LBP)anditsimprovedalgorithmsareoftensensitivetonoise.TraditionalLBPsaresolelybasedonthesignalinformationfromlocaldifferences,andthebinaryquantizationmethodoversimplifiesthelocaltexturefeatureswhiledisregardingtheimaginginformationfromtheconcaveconvexregionsbetweenthehigh-orderpixelsandtheneighboringsamplingpoints.Therefore,weproposeanimprovedDerivedMeanCompleteLocalBinaryPattern(DM_CLBP)algorithmbasedonhigh-orderderivatives.IntheDM_CLBPmethod,thegreyvalueofasinglepixelisreplacedbythemeangreyvalueoftherectangularareablock,andthedifferencebetweenpixelvaluesintheareaisobtainedusingthesecond-orderdifferentiationmethod.Basedonthecalculationconceptofthecompletelocalbinarypattern(CLBP)algorithm,thecascadesignsandmagnitudesofthetwocomponentsareencodedandrecombinedinDM_CLBPusingauniformpattern.TheresultsfromtheexperimentsshowedthattheproposedDM_CLBPdescriptorsachievedaclassificationaccuracyof94.4%.ComparedwithLBPandotherimprovedalgorithms,theDM_CLBPalgorithmpresentedinthisstudycaneffectivelydifferentiatebetweenlesionareasandnormalareasinthyroidMR,(magneticresonance)imagesandshowstheimprovedaccuracyofareaclassification.

简介：Nickel-TiO2hybridcatalystsaresynthesizedbyelectrodepositionandtheircatalyticactivitywithrespecttothehydrogenevolutionreactionisanalyzed.Twotypesoftitaniumoxideparticles,whicharecommercialparticlesofdenseTiO2andmesoporousTiO2particlessynthesizedbyanaerosolmethod,areincorporatedintothematrixofthenickelcatalyst.BothnickelcatalystscontainingTiO2particlespresentedhighercatalyticactivitythantheconventionalnickelWattscatalyst.MesoporousTiO2-modifiednickelcatalystshowedthehighestcatalyticactivitytowardsHERinalkalinemedium.Inaddition,thistypeofnickelcatalystincreasesitscatalyticactivityafterageingtreatment,whichisanindicationofanincreaseintheelectro-activeareaoftheelectrode.

简介：TwonovelasymmetricorganicsmallmoleculesofIT(2FBT-T3Cz)2andIT(2FBT-TT3Cz)2withanindenothiophene(IT)centraldonorcore,fluorinatedbenzothiadiazole(2FBT)asacceptorand3-carbazole(Cz)unitasterminalgroupweredesignedandsynthesizedasthedonormaterialsinorganicsolarcells(OSCs).Thethermal,opticalabsorption,electrochemicalproperty,hole-electronmobility,filmmorphologywerethoroughlystudied.UsingPC71BMasanelectronacceptor,withoutanyadditiveandthermalannealing(TA)treatment,theIT(2FBT-T3Cz)2-basedcellsshowedapromisingpowerconversionefficiency(PCE)of5.81%andtheIT(2FBT-TT3Cz)2-basedcellsexhibitedaPCEof4.39%.OurresultsdemonstratethattheIT-basedasymmetricsmallmoleculescanbedevelopedasapromisingclassofdonormaterialsforhighperformanceOSCs.

简介：Wedevelopahybridoptofluidicmicrocavitybyplacingamicrospherewithadiameterrangingfrom1to4μminliquid-filledplano-planoFabry–Perot(FP)cavities,whichcanprovideanextremelyloweffectivemodevolumedownto0.3–5.1μm^3whilemaintainingahighQ-factorupto1×10^4–5×10^4andafinesseof~2000.Comparedtothepureplano-planoFPcavitiesthatareknowntosufferfromthelackofmodeconfinement,diffraction,andgeometricalwalk-offlossesaswellasbeinghighlysusceptibletomirrormisalignment,ourmicrosphere-integratedFP(MIFP)cavitiesshowstrongopticalconfinementinthelateraldirectionwithatightmoderadiusofonly0.4–0.9μmandhightolerancetomirrormisalignmentaslargeas2°.Withthemicrosphereservingasawaveguide,theMIFPisadvantageousoverafiber-sandwichedFPcavityduetotheopen-cavitydesignforanalytes/liquidstointeractstronglywiththeresonantmode,theeaseofassembly,andthepossibilitytoreplacethemicrosphere.Inthiswork,themaincharacteristicsoftheMIFP,includingQ-factor,finesse,effectivemoderadiusandvolume,andtheirdependenceonthesurroundingmedium’srefractiveindex,mirrorspacing,microspherepositioninsidetheFPcavity,andmirrormisalignment,aresystematicallyinvestigatedusingafinite-elementmethod.Then,byinsertingdye-dopedpolystyrenemicrospheresofvarioussizesintotheFPcavityfilledwithwater,weexperimentallyrealizesingle-modeMIFPoptofluidiclasersthathavealasingthresholdaslowasafewmicrojoulespersquaremillimeterandalasingspotradiusofonly~0.5μm.OurresultssuggestthattheMIFPcavitiesprovideapromisingtechnologyplatformfornovelphotonicdevicesandbiological/chemicaldetectionwithultra-smalldetectionvolumes.

简介：AdditivelymanufacturedTi-6Al-4Vlatticestructureshavefoundimportantnicheapplications.However,theyoftenshowinsufficientcompressiveductilityorinsufficientstructuralintegrity.Inthisstudy,abatchof45octahedralTi-6Al-4Vlatticestructureswasmanufacturedinthreedifferentstrutdiameters(0.5,1.0,1.5mm)byselectiveelectronbeammelting(SEBM).Theinfluenceofpost-SEBMannealingonthecompressivedeformationcharacteristicsofthelatticestructurewasinvestigated.Theas-builtTi-6AI-4Vlatticesfragmentedwhenthecompressivestrainreached13%-23%dependingonstrutdiameter.Annealingat950℃(Ptransustemperature:995℃)onlyslightlyimprovedthecompressiveductilityofthelatticestructures.However,annealingat1050℃(p-annealing)fundamentallychangedthecompressivedeformationmodeofthelatticestructures.Theresultantcompressivestress-straincurvewasfeaturedbyalongsmoothplateauandnofactureoccurredevenaftersignificantdensificationofthelatticestructurehadtakenplace(>50%ofcompressivestrain).