简介：Spiralcurvesarefreefromsingularitiesandcurvatureextrema.Theseareusedinpathsmoothingapplicationstoovercometheabruptchangeincurvatureandsuper-elevationofmovingobjectthatoccursbetweentangentandcircularcurve.Linetocirclespiraltransitionismadeofstraightlinesegmentandcurvaturecontinuousspiralcurve.Itisextendibletootherimportanttypesoftransitionslikelinetolineandcircletocircle.Althoughtheproblemoflinetocircletransitionhasbeenaddressedbymanyresearchers,thereisnocomprehensiveliteraturereviewavailable.Thispaperpresentsstate-of-the-artoflinetocirclespiraltransition,applicationsindierentfields,limitationsofexistingapproaches,andrecommendationstomeetthechallengesofcompatibilitywithtoday'sCAD/CAMsoftwares,satisfactionofHermiteendconditions,approximationofdiscretedataforimageprocessing,3Dpathsmoothnessforanunmannedaerialvehicle(UAV),andarc-lengthparametrization.Wholediscussionisconcludedwithfutureresearchdirectionsinvariousareasofapplications.

简介：TheradiationfieldsoftheArchimedeanspiralantennaarederivedbyapproximatingthespiralwithaseriesofsemicircles.Thecomputationalformulaeforcalculatingtheradiationfieldsoftheairbornespiralantennasaredevelopedbyusinggeometricaltheoryofdiffraction(GTD).Thecalculatedresultsareingoodagreementwiththeexperimentalones.

简介：摘要：华南的EdiacaranDoushantuo形成的页岩包含新扁圆形macrofossil，Eoandromedaoctobrachiata，用可能是在外部膜以内的housed的八只螺线手臂描绘了。尽管八放射的结构的存在必要相似到cnidarianoctocorals以及到栉水母，与这些现存的组一起的直接相同是不大可能的。相反，我们从Doushantuo形成把注意带到最新报导的胚胎的helicospiral形态学，建议Ediacaran胚胎的metazoans的长寻求的成年人最后被发现了。

简介：Anovelintermediatefluidvaporization(IFV)technologyforLNGre-gasificationprocesswithspiral-woundheatexchangingtubesisproposed.ThenewIFVprojectcombinestheadvantageofrunningtheshellandtubeheatexchangersathighpressurewiththeadvantageofcompactspaceofheatexchangers.Thermalanalysisonthetwoprocessesofforcedconvectionandvaporizationtypeheattransferinthespiralwoundtubesandvaporcondensation/re-boilingtypeofheattransferviaintermediatefluidinshellsideshowsthefeasibilityofthispromisingtechnology.

简介：在空气描述mesoscale旋涡的不安方程的稳定的分析答案被获得。由分析3D风领域，在为不稳定的层化的物理空间的3D螺线结构被发现。在象压力和涡度地的3D分发那样的许多方面，mesoscale螺线旋涡很类似于典型地真实的气旋。关键词螺线tructure-气旋-动态系统为教育部的博士车站在非线性的科学和资金上由州的关键研究工程支持了的3D，中国。

简介：1IntroductionMechanismsoftheearth’shardcrust(crustobody)movementhavebeenhypothesizeda8tide,expansionandcontractionofthccarth,mantleconvection,rotationoftheearth,etc’,whicharenotcloselyreasoneddespiteofthesupportofsomegeologica1facts’Anothcrhypothesis-themantlecreep-flowandgeothermalencrgyconccrvatio

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简介：Anondivergentbarotropicmodel(Model1)andabarotropicprimitiveequationvortexmodel(Model2)arelinearizedrespectivelyinthispaper.Thentheirperturbationwavespectrumsarecomputedwithanormalmodeapproachtostudytheinstabilityproblemonanappointedtropicalcyclone(TC)-likevortex,thereby,thedynamicinstabilitypropertiesofspiralcloudbandsofTCsarediscussed.Theresultsshowthattheunstablemodeofbothmodelsexhibitsaspiralband-likestructurethatpropagatesawayfromthevortexoutsidetheradiusofmaximumwinds.ThediscretemodalinstabilityofthepurevortexRossbywavecanaccountforthegenerationoftheeyewallandtheinnerspiralband.TheunstablemodeinModel2hasthreeparts,i.e.,eyewall,innerandouterspiralbands.ThismodecanbeinterpretedasamixedvortexRossby-inertiagravitationalwave.TheunbalancedpropertyofthewaveoutsidethestagnationradiusofthevortexRossbywaveisoneoftheimportantreasonsfortheformationoftheouterspiralbandinTCs.Accordingly,theouterspiralbandcanbeidentifiedtopossesspropertiesofaninertial-gravitationalwave.Whentheformationofunstableinnerandouterspiralbandsisstudied,abarotropicvortexmodelshallbeused.Inthismodel,themostunstableperturbationbearstheattributesofeitherthevortexRossbywaveortheinertial-gravitationalwave,dependingonthevortexradius.Sosuchperturbationsshallbeviewedasanunbalancedandunstablemixedwaveofthesetwokindsofwaves.

简介：AbstractBackground:Certain hemophilia patients are unable to cooperate with or afford magnetic resonance imaging (MRI) examinations. The purpose of our study was to explore the value of multislice spiral computed tomography (MSCT) in evaluating hemophilic arthropathy (HA).Methods:Thirty-eight patients with 73 joints of HA were consecutively selected from January 2016 to May 2018 for this prospective study. All 73 joints were examined by X-ray, CT, and MRI within 2 days. The MRI scores of the joints were determined by the International Prophylaxis Study Group (IPSG) standard. The CT findings were quantified according to the IPSG standard, except for cartilage injury, which was quantified by joint space narrowing using the X-ray Pettersson score. The CT and MRI scores were compared by the paired Wilcoxon signed-rank test. The correlations between the CT score of joint space narrowing and MRI score of cartilage injury and the total CT and MRI scores were analyzed by Spearman rank correlation. The kappa test was used to compare the consistency of CT and MRI scores.Results:MRI was superior to CT based on the scores for small amount of effusion (P < 0.05), synovial hypertrophy and hemosiderin deposition in the mild groups (P < 0.05). The CT and MRI scores were not significantly different for moderate and massive effusion, synovial hypertrophy, and hemosiderin deposition in the moderate and severe groups, bone erosion or cystic changes (P > 0.05), and there was a high degree of consistency between the two scores (kappa > 0.81). The consistency between the Pettersson scores of joint space narrowing on CT and the IPSG scores of cartilage injury on MRI was high (kappa = 0. 774, P < 0.05).Conclusion:The image scores of MSCT are generally consistent with MRI except for mild synovitis, which can be used as an alternative for the evaluation of HA.

简介：Thispaperpresentsastudyonpotentialinstabilityandspiralstructureofunstablerainclusters.First,wedevelopalinearizednon-axisymmetricalmathematicmodelforrainclustersincircularcylindricalcoordinatesandacquireitsanalyticsolution.Second,wediscussthepotentialinstabilityofnon-axisymmetricalrainclusters.Finally,weconcludethatspiralstructurescanexistinrainclusters.Ouranalysisindicatesthatpotentialinstabilityoccurswhenhumidstratificationcoefficientislessthanzero.Unstablegrowthrateincreaseswiththeincreaseoftheabsolutevalueforhumidstratificationcoefficient.Thesimplertheverticalstructureofperturbation,thethickertheinversionlayer;additionally,thesmallertheradiusoftherainclusters,thelargertheunstablegrowthrate.Simulationresultsagreewellwiththosefromobservationandforecast.Thespiralstructuresimulatedbyourmodelissimilartoaradarecho,suggestingthatrainclusterswithspiralstructurescanoccurintheatmosphere.Inaddition,theyaregenerallyclosetothemodelsolutioninthiswork.

简介：Thereisasignificantdiferencebetweenthecalculationbasedonthetheoryofgeneralrelativityandobservationofrotationcurvesofspiralgalaxies.Todescribethisdiscrepancy,twodistincttheorieshavebeenproposedsofar:existenceofdarkmatterandmodificationofunderlyinggravitationaltheory.Intheabsenceofdarkmatter,itisassumedthatthetheoryofgeneralrelativityongalacticscalesneedstobemodified.Thisletterisdevotedtoexplainingthisdiferenceinamodifiedteleparallelgravity.Weshowthatmodifiedteleparallelgravityfavorsflatnessofrotationcurvesofspiralgalaxiesmuchinthesamewayasobservationshows.

简介：Numericalsimulationconcerningtheformingandweldingprocessofspiralweldedpipewasconducted,whichincludedthreesteps:thefirststepwasthestressanalysiswhenthespiralwasformed,andthenthestresswasregardedasinitialconditionofmeldingduringthetemperaturefieldanalysisintheprocessofwelding,thelaststepwasthethermalstressanalysisoftheweldseamaftertheweldingwasover.Moreover,whenthesteelstripwaspushed,thestresswasalsocalculatedbynon-linearitycontacttechnologyusingAbaqusSoftware.Byfiniteelementmodelingandcalculatingoftheformingandweldingprocessofthespiralweldedpipe,thekeypointsofthemulti-fieldssyntheticsimulatingwerestudiedanddiscussed.

简介：Distinguishingwithtraditionaltoothprofileofspiralbevelandhypoidgear,itproposedanewtoothprofilenamelythesphericalinvolute.Firstly,anewtheoryofformingthesphericalinvolutetoothprofilewasproposed.Then,thistheorywasappliedtocompleteparametricderivationofeachpartofitstoothprofile.Forenhancingtheprecision,theSWEEPmethodusedforformationofeachpartoftoothsurfaceandG1stitchingschemaforobtainingaunifiedtoothsurfaceareputforwardandmadetheapplicationintheaccuratemodeling.Lastly,owingtothehigheraccuracyoftoothsurfaceofoutputtedmodel,itgavesomeoptimizationapproaches.Givennumericalexampleaboutthemodelcanshowthatthisdesignedgearwithsphericalinvolutetoothprofilecanachievefastandaccurateparametricmodelingandprovideafoundationfortoothcontactanalysis(TCA)indigitizeddesignandmanufacture.更多还原

简介：Becauseofitsgoodconditionwithmechanics,logarithmicspiraldoublecurvearchbamhasbeenwidelyusedinthepracticalengineering.Theintroductionofanewmethodinhowtodividetransversejointinarchdamwillbegivenandthefurtherresearchofitscalculationhasbeendone.TheC++isusedinelectronicprocedureandthe3DsimulationhasbeenfinishedwithAutoCAD,whichwillprovidetheobjectmodelforcomputersimulationofthearchdamandthedivisionoffiniteelementmesh.Meanwhile,thismethodindividingthetransversejointinarchdamalsocanbetakenasthecalculatedbasisforthedesignandcalculationofarchdam,constructionloftingandthecalculationoftheworkamount.

简介：Inopticalscanningholography,onepupilproducesasphericalwaveandanotherproducesaplanewave.Theyinterferewitheachotherandresultinafringepatternforscanningathree-dimensionalobject.Theresolutionofthehologramreconstructionisaffectedbythepointspreadfunction(PSF)oftheopticalsystem.Inthispaper,wemodulatethePSFbyaspiralphaseplate,whichsignificantlyenhancesthelateralanddepthresolution.Weexplainthetheoryforsuchresolutionenhancementandshowsimulationresultstoverifytheefficacyoftheapproach.

简介：由使用WRFmesoscale模型，这份报纸在在7月19日的时期期间登陆台风Haitang到20附近执行数字模拟和不对称的螺线雨乐队的结构的特征的诊断分析，2005。结果显示与降水中心联系的二根雨线主要台风中心向东北被定位。南部的雨线的运动和紧张与850-hPa相应很好从0200～1800UTC2005年7月19日的积极涡度乐队。在气旋的循环的效果下面，在850hPa的积极涡度乐队与一个南部的雨乐队一起连接了，导致在降水的南部的中心的降雨的增强。向南方的雨线逐渐地移动了向，加强在降水的北中心的降雨然后合并与向北方一个。而且，在重降雨之间的关系和分叉回答垂直砍在高高度的风被分析。最后，关系在低高度在降水的二个中心附近在对流涡度向量和降雨的垂直部件的发展之间被揭示。

简介：ObjectiveTostudytheeffectofsalicylateontheexpressionandfunctionofNMDAreceptorsinspiralganglionneurons(SGNs).MethodsThemRNAofNR1subunitofNMDAreceptorinmodiolustissuesweredetectedbyRealtimefluorescencequantitativePCR(FQ-PCR).NMDAreceptorwhole-cellcurrentswererecordedusingpatchclampinacuteisolatedSGNs.ResultsComparedwiththecontrolgroup,salicylatesignificantlyincreasedthemRNAlevelofNR1subunitinSGNs.NMDAofconcentrationsrangingfrom0.1mMto10mMevokednocurrentinSGNs.NMDA(0.1mMand0.5mM)appliedwithsalicylate(5mM),however,inducedinwardcurrents(212.6±15.2pA,n=5;607.9±44.3pA,n=5)inadose-dependentmanner,whichcouldbeinhibitedbyAPV.SalicylatealonedidnotproduceanycurrentinSGNs.ConclusionSalicylateincreasestheexpressionofNMDAreceptorsandfacilitatesthecurrentsmediatedbyNMDAreceptorsinSGNs.

简介：Inthispaper,variousstrategiesofspiralirradiatingschemefortheflameformingofabowlshapedsurfaceareinvestigatedexperimentallyandnumerically.Experimentalworkisperformedusingaflametorchintegratedwitha2-axisCNCworkstation.TheABAQUSimplicitsolverisusedinthenumericalsimulation.Threedifferentstrategiesofthespiralirradiatingschemeareinvestigatedfortheflameformingofabowlshapedsurface.ThefirststrategyistheSimplespiralirradiatingscheme,thesecondistheRotationalspiralirradiatingscheme,andthethirdistheSymmetrical-Rotationalspiralirradiatingscheme.TheresultsshowthatusingtheSymmetricalRotationalspiralirradiatingscheme,abowlshapedsurfacewiththemaximumdeformationcanbeproduced,followedbyusingtheRotationalscheme,andtheSimplespiralscheme.ItisalsoconcludedfromtheresultsthatthespiralirradiatingschemewithSymmetrical-Rotational,RotationalandSimplespiralschemesleadtothemaximumsymmetriesintheproducedbowlshapedsurface,respectively.Allthenumericalresultsareingoodagreementwiththeexperimentalobservations.

简介：Takingspiralchuteasexample,amethodofunfoldeddrawingsandviewsaboutirregularspiralsurfaceisintroduced.Thesurfaceisundevelopableandtoocomplicatedtogetitsviewsortodrawunfoldeddrawingsbymanualmethod.Inthisarticle,aseriesoftheboundaryequationsofthespiralchutearederivedbythemovementruleofcoalflow,andthesolidandviewsofthespiralchutearegeneratedbasedonredevelopmentofSolidWorks.Unfoldeddrawingisdrawnapplyingtriangulardevelopmentprinciple.Theviewsandunfoldeddrawingsnotonlyareproducedautomatically,preciselyandparameterized,butalsoinvolvemoretechnologicalinformation.Soithasanimportantsignificanceontheirregularspiralsurface’sdevelopmentsandprocessing.

简介：在一个二维的方形的数组的螺线波浪的开发由于部分离子隧道块(钾，钠)被调查，节点的动力学被HodgkinHuxley神经原描述，这些神经原最近被结合邻居连接。参数比率xNa(并且xK)，它定义钠(钾)的工作离子隧道数字的比率到钠的全部的离子隧道数字(并且钾)，被用来测量隧道块导致的移动传导力。在二参数的阶段空间(参数比率对毒害的区域)的统计可变R的分发广泛地被计算为部分离子隧道块导致的螺线波浪的转变标记参数区域，有同步R的更小的因素的区域被联系那个螺线波浪使明白毒害的隧道、柔韧的参数区域。当毒害的区域(钾或钠)和沉醉的度是小的时，螺线波浪保持活着，不同转变(死亡，几个螺线波浪共存或多手臂螺线波浪出现)发生在中等比率xNa下面(并且xK)当堵住的区域的尺寸超过某些阀值时。螺线波浪的决裂发生，螺线的多手臂飘动当隧道噪音被考虑时，被观察。