简介:Inthispapertheauthorsgeneralizetheclassicrandombipartitegraphmodel,anddefineamodeloftherandombipartitemultigraphsasfollows:letm=m(n)beapositiveinteger-valuedfunctiononnandζ(n,m;{pk})theprobabilityspaceconsistingofallthelabeledbipartitemultigraphswithtwovertexsetsA={a_1,a_2,...,a_n}andB={b_1,b_2,...,b_m},inwhichthenumberst_(ai),b_joftheedgesbetweenanytwoverticesa_i∈Aandb_j∈BareidenticallydistributedindependentrandomvariableswithdistributionP{t_(ai),b_j=k}=pk,k=0,1,2,...,wherepk≥0and∞Σk=0pk=1.TheyobtainthatX_(c,d,A),thenumberofverticesinAwithdegreebetweencanddofG_(n,m)∈ζ(n,m;{pk})hasasymptoticallyPoissondistribution,andanswerthefollowingtwoquestionsaboutthespaceζ(n,m;{pk})with{pk}havinggeometricdistribution,binomialdistributionandPoissondistribution,respectively.Underwhichconditionfor{pk}cantherebeafunctionD(n)suchthatalmosteveryrandommultigraphG_(n,m)∈ζ(n,m;{pk})hasmaximumdegreeD(n)inA?underwhichconditionfor{pk}hasalmosteverymultigraphG(n,m)∈ζ(n,m;{pk})auniquevertexofmaximumdegreeinA?
简介:Puretungsten(PW)andW-1wt%La2O3(WL10)werepreparedbypowdermetallurgicalroutefollowedbytheswaging+rollingprocess.Thelogarithmicstrainsare0,0.37,0.58,and0.98forWL10and0,0.58forPW.Heattreatmentswereperformedattemperaturesvariedfrom1,573to2,173Ktodeterminetherecrystallizationtemperature.Recrystallizationtemperaturesare1,973and2,173KforWL1(logarithmicstrainof0.37)andWL3(logarithmicstrainof0.98),respectively.ButinthecaseofWL2(logarithmicstrainof0.58),fullrecrystallizationisnotachievedattemperatureofabove2,173K.Furthermore,therecrystallizationtemperatureofPWwithlogarithmicstrainof0.58isatleast300KlowerthanthatoftheequivalentWL10sample.Moreover,theincreaseofrecrystallizationtemperatureinhibitsthestrengthdegradationofWL2:sampleslose4%and22%strengthwhenannealedat1,573and1,973Kcomparedwithroomtemperature(RT)sample.Finally,thetextureevolutionfortheswaged+rolledWL10issignificantlyrelatedtothedeformationdegree:thedominatedorientationis<001>forWL2while<110>forWL3.
简介:Withrespecttothedecisionmakingproblemswherealotoffuzzyandgreyinformationalwaysexistsinthereal-lifedecisionmakinginformationsystem,itisdifficultforsuchuncertaintymethodsasfuzzymathematics,probability,andintervalnumberstodealwith.Tothisend,basedonthethoughtandmethodofgreynumbers,greydegreesandintervalnumbers,theconceptofdominancegreydegreeisdefined.Andthenamethodofrankingintervalgreynumbersbasedonthedominancegreydegreeisproposed.Afterdiscussingtherelevantproperties,thepaperfinallyusesanexampletodemonstratetheeffectivenessandapplicabilityofthemodel.Theresultshowsthattheproposedmodelcanmoreaccuratelydescribeuncertaintydecisionmakingproblems,andrealizethetotalorderingprocessformultiple-attributedecision-makingproblems.
简介:AbstractObjectives:To demonstrate three-hundred and sixty degrees of maxillary sinus (MS) surgical approaches using cadaveric dissections, highlighting the step-by-step anatomy of each procedure.Methods:Two latex-injected cadaveric specimens were utilized to perform surgical dissections to demonstrate different approaches to the MS. The procedures were documented with macroscopic images and endoscopic pictures.Results:Dissections were performed to approach the MS medially (endoscopic maxillary antrostomy and ethmoidectomy), anteriorly (Caldwell-Luc), superiorly (transconjunctival/transorbital approach), inferiorly (transpalatal approach), and posterolaterally (preauricular hemicoronal approach).Conclusion:A number of approaches have been described to address pathology in the MS. Surgeons should be familiar with indications, limitations, and surgical anatomy from different perspectives to approach the MS. This paper illustrates anatomic approaches to the MS with detailed step-by-step cadaveric dissections and case examples.
简介:Azero-dimensionalmodelwhichincludes56speciesofreactantsand427reactionsisusedtostudythebehaviorofchargedparticlesinatmosphericplasmaswithdifferentionizationdegreesatlowaltitude(near0km).TheconstantcoefficientnonlinearequationsaresolvedbyusingtheQuasi-steady-stateapproximationmethod.Theelectronlifetimesareobtainedforafterglowplasmawithdifferentinitialvalues,andthetemporalevolutionsofthemainchargedspeciesarepresented,whicharedominantinreactionprocesses.Theresultsshowthattheelectronnumberdensitydecaysquickly.Thelifetimesofelectronsareshortenedbyabouttwoorderswithincreasingionizationdegree.Electronsthenattachtoneutralparticlesandproducenegativeions.Whentheinitialelectrondensitiesareintherangeof1010~1014cm3,thenegativeionshavesufficientlyhighdensitiesandlonglifetimesforairpurification,disinfectionandsterilization.Electrons,O2,O4,CO4andCO3arethedominantnegativespecieswhentheinitialelectrondensityne0≤1013cm3,andonlyelectronsandCO3areleftwhenne0≥1015cm3.N+2,N+4andO+2aredominantinthepositivechargesforanyionizationdegree.Otherpositivespecies,suchasO+4,N+3,NO+,NO+2,Ar+2andH3O+·H2O,aredominantonlyforacertainionizationdegreeandinacertainperiod.
简介:Inthisletter,apiezoaeroelasticenergyharvesterbasedonanairfoilwithdoubleplungedegreesoffreedomisproposedtoadditionallytakeadvantageofthevibrationalenergyoftheairfoilpitchmotion.Ananalyticalmodeloftheproposedenergyharvestingsystemisbuiltandcomparedwithanequivalentmodelusingthewell-exploredpitch-plungeconfiguration.Thedynamicresponseandaveragepoweroutputoftheharvesterarenumericallystudiedastheflowvelocityexceedsthecut-inspeed(flutterspeed).Itisfoundthattheharvesterwithdouble-plungeconfigurationgenerates4%–10%morepowerwithvaryingflowvelocitieswhilereducing6%ofthecut-inspeedthanitscounterpart.
简介:Itisawell-knownfactthatcharactersofafinitegroupcangiveimportantinformationaboutthestructureofthegroup.Itwasalsoprovedbythethirdauthorthatafinitesimplegroupcanbeuniquelydeterminedbyitscharactertable.Heretheauthorsattempttoinvestigatehowtocharacterizeafinitealmost-simplegroupbyusinglessinformationofitscharactertable,andsuccessfullycharacterizetheautomorphismgroupsofMathieugroupsbytheirordersandatmosttwoirreduciblecharacterdegreesoftheircharactertables.
简介:Pointabsorberwaveenergydevicewithmultipledegreesoffreedom(DOF)isassumedtohaveabetterabsorptionabilityofmechanicalenergyfromoceanwaves.Inthispaper,acoaxialsymmetricarticulatedpointabsorberwaveenergyconverterwithtwodegreesoffreedomispresented.Themechanicalequationsoftheoscillationbuoywithpowertake-offmechanism(PTO)inregularwavesareestablished.Thethree-dimensionalnumericalwavetankisbuiltinconsiderationofthebuoymotionbasedupontheCFDmethod.Theappropriatesimulationelementsareselectedforthebuoyandwaveparameters.ThefeasibilityoftheCFDmethodisverifiedthroughthecontrastbetweenthenumericalsimulationresultsoftypicalwaveconditionsandtestresults.Insuchcase,thebuoywithsingleDOFofheave,pitchandtheircouplingmotionconsideringfree(noPTOdamping)anddampedoscillationsinregularwavesaresimulatedbyusingtheverifiedCFDmethodrespectively.Thehydrodynamicandwaveenergyconversioncharacteristicswithtypicalwaveconditionsareanalyzed.Thenumericalresultsshowthattheheaveandpitchcanaffecteachotherinthebuoycouplingmotion,hydrodynamicloads,waveenergyabsorptionandflowfield.ThetotalcapturewidthratiowithtwocoupledDOFmotionishigherthanthatwithasingleDOFmotion.ThewaveenergyconversionofacertainDOFmotionmaybehigherthanthatofthesinglecertainDOFmotioneventhoughthewaveisattheresonanceperiod.Whenthewaveperiodsarehighenough,theinteractionbetweenthecoupledDOFmotionscanbeneglected.
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简介:在这份报纸,CD衍生物的三种不同类型作为原子转移激进分子聚合(ATRP)被综合开始者或可逆增加破碎链转移聚合(木排)链转移。为每衍生物的替换的度小心地被描绘通过<啜class=“a-plus-plus”>1H-NMR,<啜class=“a-plus-plus”>13C-NMR光谱学和飞行团spectrometry(MALDI-TOF-MS)的帮助矩阵的激光解吸附作用/电离时间。影响替换的度的因素被讨论。而且,在ATRP和木排之间的比较在N-isopropylacrylamide(NIPAM)的聚合被显示出。