简介:<正>Ethnomusicologyasanemergingdisciplinehasmanykindofstatement.ThroughreadingMkolinski’article《ThesubjectandmethodofEthnomusicology》andthinkofethnomusicologyresearch.TheethnomusicologyIntheprocessofdevelopmentusedtomanykindsofMethodologyandinthisarticlesothatmethodologybycomparingtheperiodscholarswecanfoundethnomusicologyinthecourseofhistory.Thisarticledescribesthemethodfromanumberofmusicologists.
简介:IntroductionThoughsingularBoundaryelementisregardedasakindofweightedresiduals,thesingularboundaryelementhasauniquecharacteris...
简介:Underinspirationfromthestructure-preservingpropertyofsymplecticdifferenceschemesforHamiltoniansystems,twohomogenizationconditionsforarepresentativeunitcelloftheperiodicalcompositesareproposed,oneconditionistheequivalenceofstrainenergy,andtheotheristhedeformationsimilarity.Basedonthesetwohomogenizationconditions,aneigenelementmethodispresented,whichischaracteristicofstructure-preservingproperty.Itfollowsfromthefrequencycomparisonsthattheeigenelementmethodismoreaccuratethanthestiffnessaveragemethodandthecomplianceaveragemethod.
简介:Anewmethodforestimationtheboundsofeigenvaluesispresented.InordertoshowthatthemethodproposeisaseffectiveasQiu’s,anundampingspring-masssystemwith5nodesand5degreesoffreedomisgiven.Toillustratethatthepresentmethodcanbeappliedtostructureswhichcannotbetreatedbynon-negativedecompsition,aplandframewith202nodesand357beamelementsisgiven.TheresultsshowthatthepresentmethodiseffectiveforestimatingtheboundsofeigenvaluesandismorecommonthanQiu’s.
简介:Asimplifiedmultisupportresponsespectrummethodispresented.Thestructuralresponseisasumoftwocomponentsofastructurewithafirstnaturalperiodlessthan2s.Thefirstcomponentisthepseudostaticresponsecausedbytheinconsistentmotionsofthestructuralsupports,andthesecondisthestructuraldynamicresponsetogroundmotionaccelerations.Thismethodisformallyconsistentwiththeclassicalresponsespectrummethod,andtheeffectsofmultisupportexcitationareconsideredforanymodalresponsespectrumormodalsuperposition.Iftheseismicinputsateachsupportarethesame,thesupportdisplacementscausedbythepseudostaticresponsebecomerigidbodydisplacements.Theresponsespectruminthecaseofmultisupportexcitationsthenreducestothatforuniformexcitations.Inotherwords,thismultisupportresponsespectrummethodisamodificationandextensionoftheexistingresponsespectrummethodunderuniformexcitation.Moreover,mostofthecoherencycoefficientsinthisformulationaresimplifiedbyapproximatingthegroundmotionexcitationaswhitenoise.Theresultsindicatethatthissimplificationcanreducethecalculationtimewhilemaintainingaccuracy.Furthermore,theinternalforcesobtainedbythemultisupportresponsespectrummethodarecomparedwiththoseproducedbythetraditionalresponsespectrummethodintwocasestudiesofexistinglong-spanstructures.Becausetheeffectsofinconsistentsupportdisplacementsarenotconsideredinthetraditionalresponsespectrummethod,thevaluesofinternalforcesnearthesupportsareunderestimated.Theseregionsareimportantpotentialfailurepointsanddeservespecialattentionintheseismicdesignofreticulatedstructures.
简介:Theregularizedimageinterpolationmethodiswidelyusedbasedonthevectorinterpolationmodelinwhichdown-samplingmatrixhasverylargedimensionandneedslargestorageconsumptionandhighercomputationcomplexity.Inthispaper,afastalgorithmforimageinterpolationbasedonthetensorproductofmatricesispresented,whichtransformsthevectorinterpolationmodeltomatrixform.Theproposedalgorithmcanextremelyreducethestoragerequirementandtimeconsumption.Thesimulationresultsverifytheirvalidity.
简介:Anewandefficienttechniquefordeterminingoptimallocationsofsensorsandactuatorsofintelligentstructuresispresented.Theoptimizationofsensorandactuatorlocationsisbasedonthe1stordersingularvalueperturbationsofobservabilityandcontrollability.Usingthismethodtheoptimalplacementsofsensorsandactuatorsoftheintelligentstructurercanbeselected.Twonumericalexamplesaregiventodemonstratetheapplicationsofthemethod.Theimpulseresponsesofstructuresduetodifferentlocationsofactuatorswiththesamecontrollawareanalyzedindetail.
简介:Givennpropositionalvariables,letKn(i,j),0≤i≤j≤n,betheset(ordisjunction)ofallconjunctionsofiliteralsofwhichexactlyjliteralsarenegative.DunhamandWangconjecturedthatitmayrequireexponentialtimetodecidethateverydisjunctionKn(i,j)isnotvalidbytheresolutionmetho.Thispapergivesaproofoftheconjectureandthenexhibitsanewcounterexampletothefeasibilityoftheresolutionorconsensusmethod.
简介:AbstractInthispaper,anewSQPmethodforinequalityconstrainedoptimizationisproposedandtheglobalconvergenceisobtainedunderverymildconditions.
简介:AsanewwaytolearnEnglish,lexicalchunkisverysignificant.ThisthesisdiscussesproblemsthatChineseEnglishlearnersmetinlearninglexicalchunks,includingovergeneralization,incorrectanalogies,Chineseexpressionusedintranslationandimproperlearningstrategies.Thisthesisintroducessomenewwaystolearnlexicalchunksinordertostrengthenstudents’senseoflexicalchunk.
简介:Anewiterativemethodforsignal,restorationhasbeenpresented.AnestimateoperatorW_κwhichisrelatedtoerroroperatorB_κintherestorationprocessisintroducedtodecreasetheestimateerrorandincreasetheconvergencerate.Theeffectofnoiseontheestimateprocesshasalsobeendescribed.Finally,themethodhasbeenappliedtothedeconvolutionofablurredsignal,andtheresultsvalidatethemethod.Acomparisonbetweenthepresentedmethodandthegeneralmethodhasalsobeengiven.
简介:Aprecisetwo-degree-of-freedommeasuringsystem(2DMS)isdevelopedbasedonsingle-modeopticalfiber,LD,cubecornerretroreflectorandfour-quadrantphotodetector(4-Q),andthesimultaneouson-linemeasurementoflateralandverticaldirectionstraightnesserrorsofthelinearstageiscarriedout.Themovingpartiswireless,whicheliminatesanyerrorsintroducedbypushingandpullingthewires.Thesensitivityofthestraightnesserrormeasurementcanbeimprovedbyafactorof2withthecubecornerretroreflector.Thisfiber-basedopticallyalignedbeamisusedtoestablishareferencelineforthestraightnessmeasurementofanymechanicalsystem.4-Qdetectorisusedtoreceivethelaserbeam.Achipmicrocomputerisdevelopedtoconductalldataacquisitionandsignalprocessing.Thebeamdriftinfluencecanberemovedinthegreatestextentfromthesystem.Theexperimentsonthemeasurementsystemstability,repeatabilityanditscomparisonwiththeHP5528double-frequencylaserinterferometerarecarriedout.