简介:X-rayimagingistheconventionalmethodfordiagnosingtheorthopedicconditionofapatient.ComputerizedTomography(CT)scanningisanotherdiagnosticmethodthatprovidespatient’s3Danatomicalinformation.However,bothmethodshavelimitationswhendiagnosingthewholeleg;X-rayimagingdoesnotprovide3Dinformation,andnormalCTscanningcannotbeperformedwithastandingposture.Obtaining3Ddataregardingthewholeleginastandingpostureisclinicallyimportantbecauseitenables3Danalysisintheweightbearingcondition.Basedontheseclinicalneeds,ahardware-basedbi-planeX-rayimagingsystemhasbeendeveloped;itusestwoorthogonalX-rayimages.However,suchmethodshavenotbeenmadeavailableingeneralclinicsbecauseofthehightcost.Therefore,weproposedawidelyadaptivemethodfor2DX-rayimageand3DCTscandata.Bythismethod,itispossibletothreedimensionallyanalyzethewholeleginstandingposture.TheoptimalpositionthatgeneratesthemostsimilarimageisthecapturedX-rayimage.Thealgorithmverifiesthesimilarityusingtheperformanceoftheproposedmethodbysimulation-basedexperiments.Then,weanalyzedtheinternal-externalrotationangleofthefemurusingrealpatientdata.Approximately10.55degreesofinternalrotationswerefoundrelativetothedefinedanterior-posteriordirection.Inthispaper,wepresentausefulregistrationmethodusingtheconventionalX-rayimageand3DCTscandatatoanalyzethewholelegintheweight-bearingcondition.
简介:Wetackletheproblemofconstructing2DcentroidalVoronoitessellationswithconstraintsthroughanefficientandrobustconstructionofboundedVoronoidiagrams,thepseudo-dualoftheconstrainedDelaunaytriangulation.WeexploitthefactthatthecellsoftheboundedVoronoidiagramcanbeobtainedbyclippingtheordinaryonesagainsttheconstrainedDelaunayedges.Theclippingitselfisefficientlycomputedbyidentifyingforeachconstrainededgethe(connected)setoftriangleswhosedualVoronoiverticesarehiddenbytheconstraint.TheresultingconstructionisamenabletoLloydrelaxationsoastoobtainacentroidaltessellationwithconstraints.
简介:The2Dplanegasflowunderheating(withnonentityboundarycondition)hasbeendiscussedbytheanalyticalapproachinthispaper.Theapproximateanalyticalsolutionshavebeenobtainedfortheflowpassingvariouskindsofheatsources.Solutionsdemonstratethethermaldisplacementphenomenaarestronglydependontheheatingintensity.
简介:Cavitationisoneofthetroublesomeproblemsinrocketturbopumps,andsincemostofhigh-efficiencyrocketpropellantsarecryogenicfluids,socalled'thermodynamiceffect'becomesmoreevidentthaninwater.Inthepresentstudy.numericalandexperimentalstudyofliquidnitrogencavitationin2DLavalnozzlewascarriedout,sothattheinfluenceofthermodynamiceffectwasexamined.Itwasrevealedthattemperatureandcavitationhavestronginter-relationshipwitheachotherinthermo-sensitivecryogenicfluids.
简介:Thenew-typetractionboundaryintegralequationsdevelopedbyHuandwithnohypersingularintegralareappliedtoanalysisof3Dfinitecrackedbodies.Anumericalalgorithmforgeneral3Dproblemsandasemi-analyticaloneforaxisymmetricproblemsarepresented.Someexamplesofthickplatesandcylindricalcolumnsincludingpenny-shapedcrack(s),andrectangularplatesincludinganellipticalcracknormaltothesurfaceareanalyzed.Thecomparisonbetweenpresentresultsandthoseinliteratureshowsthehighaccuracyandeffectivenessofthepresentmethod.
简介:Solutionstoapiezoelectrichalf-planewithafixedconductorsurfaceelectrodesubjectedtotwogeneralizedsingularities(linedislocationand/orlineforceandfreecharge)arepresented.Coulombforcesactingonthesingularitiesduetotheboundarypolarizationchargesofmediumandtheinductioncharg-esofconductorelectrodeareanalyzedindetail.Theinteractionbetweenthetwosingularitiesisalsoanalyzednumerically.ResultsshowthatCoulombforceswillbecomeimportantasthefreechargeapproachestheboundaryortwosingularitiesmoveclosely.
简介:PhaseShiftingAndLogicalMoire(PSALM)isakindofcomputerimageprocessingmethodwhichcanbeusedinphasemeasurementandtoobtaintheshape,deformationandstraindistributionofanobject.Thispaperpresentsthestructureandworkingprocedureofa2DphasemeasurementPSALM2Dprogramanditsapplication.Whenanalyzingmoireinterferometricfringes,wecanobtain2Ddistributionofdisplacementandstrain.Whenitisusedinreflectionmoirewecanmeasuretheslopeofaspecimen.SatisfactoryvisualizationandquantitativeresultsaregivenbyPSALM2D.
简介:连贯的多角形的粒子的二维的分离元素模型(DEM)模拟被开发了估计点来源颤动的利益在楔形的hoppers导致流动。使用的particleparticle相互作用模型基于一个多接触原则。没有颤动,学习的第一部分在严肃下面调查了粒子分泌物决定批评的孔尺寸(Bc)就作为粒子形状的功能支撑流动。多角形形状的粒子比圆形的粒子需要一个更大的孔,这被显示出。当粒子顶点的数字增加,Bc减少,这也被显示出当粒子顶点的数字增加。圆形的粒子的增加以一种线性方式支持多角形的流动。学习的第二部分证明那颤动能提高流动,有效地减少Bc。模型表明了震荡器地点(高度)的重要性,与在提高的以前的连续统模型结果,和颤动振幅一致流动。
简介:Commerciallyavailablelatticescontainvariouskindsofmorphologicalimperfectionswhichresultingreatdegradationinlattices’mechanicalproperties,therefore,toobtainimperfectioninsensitivelatticestructureisobviouslyapracticalresearchsubject.Hierarchicalstructurematerialswerefoundtobeaclassofpromisinganti-defectmaterials.Thispaperbuildshierarchicallatticebyaddingsoftadhesiontolattice’scelledgesandnumericalresultsshowthatitsimperfectionsensitivitytomissingbarsisminorcomparedwiththeclassiclattice.Softadhesionwithappropriatepropertiesreinforcecelledge’sbendingstiffnessandthusreducethebendingdeformationinlatticecausedbymissingbarsdefect,whichisconfirmedbystatisticalanalysisofnormalizednodedisplacementsofimperfectlatticesunderhydrostaticcompressionandshearloads.