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16 个结果
  • 简介:BasedontheGlobalRegionalAssimilationandPredictionSystem-TropicalCycloneModel(GRAPES-TCM),anensembleforecastexperimentwasperformed,inwhichTyphoonWiphaduringtheperiodimmediatelypriortolandfallwasselectedforthestudyandthebreedingofgrowingmode(BGM)methodwasusedtoperturbtheinitialconditionsofthevortexfieldandtheenvironmentfield.TheresultsoftheexperimentindicatethateachmemberhadadifferentinitialstatusinBGMprocessingandtheyshowareasonablespreadamongmembersalongwiththeforecastphase.Changesinthelarge-scalefield,thermodynamicstructure,andspreadamongmemberstookplacewhenWiphamadelandfall.Thesteeringeffectofthelarge-scalefieldandtheinteractionbetweenthethermodynamicsandthedynamicsresultedindifferenttracksofthemembers.Meanwhile,theforecastuncertaintyincreased.Insummary,theensemblemeandidnotperformaswellasthecontrolforecast,buttheclustermeanprovidedsomeusefulinformation,andperformedbetterthanthecontrolinsomeinstances.Thepositionerrorwas34kmfor24hforecast,153kmfor48hforecast,and191kmfor66hforecast.Thestrikeprobabilitychartqualitativelydescribedtheforecastuncertainty.

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  • 简介:UsingthemethodofSingularSpectrumAnalysis(SSA),theevolutionregularityoftropicalcycloneslandinginGuangdongareanalyzed.ThemainperiodsofyearlytopicalcycloneslandinginGuangdongarefoundat8andquasi-3years,andinthewestofPearlRiverMouthare12andquasi-2yearstothewestofPearlRiverMouth.ThenorthwestPacificthattopicalcyclonesaregeneratedisdividedinto8areas,andtheSea-SurfaceTemperature(SST)ineachareaisanalyzedusingSSA.ThemainperiodsofNINO-westare8and3years,andthoseofthewarmpoolare12and2years,respectively.ThismaybethephysicalreasonforthegenerationtropicalcycloneslandinginGuangdong.BycombiningtheMaximumEntropyMethod(MEM)withSSA(SSA-MEM),theyearlyvariationtrendoftropicalcycloneslandinginGuangdongandthePearlRiverMouthareforecast,andtheresultsaregood.Themethodcanbeusedinoperationalshort-rangeclimateforecast.

  • 标签: 热带气旋 频谱分析 年变化 周期
  • 简介:THEDYNAMICSOFMAINTAININGTHETROPICALCYCLONE9012AFTERITSLANDING¥LiangLi,WuZhiwei(MeteorologicalInstituteofFujianProvince,Fuzhou...

  • 标签: long maintenance ANGULAR MOMENTUM transport SPIN-UP
  • 简介:目的:探寻下落在内翻结合跖屈表面时踝关节运动学参数和腓肠肌内侧、腓骨长肌、胫骨前肌的肌电活动情况。方法:12名运动员从30cm高度下落时3种不同条件的表面:平面、25°内翻表面、25°内翻结合25°跖屈表面,每种条件分别采集5次落地。用单因素方差分析运动学参数,同时采用3×3双因素方差分析3种肌肉的积分肌电值(p<0.05)。结果:积分肌电值结果显示不同肌肉和表面之间存在交互作用。下落于平面时胫骨前肌的肌电活动高于另两种表面。相比较平面,下落于内翻表面的最大内翻角度和角速度明显提高,但腓骨长肌的肌电活动却相似。此外,下落于内翻结合跖屈的表面,其腓肠肌的积分肌电、踝关节的跖屈角度和内翻的关节活动度明显高于25°的内翻表面。结论:与单纯的内翻表面相比,内翻结合跖屈的表面在下落时会产生更不稳定的落地状况,从而更易造成踝关节扭伤。

  • 标签: 联合反演 肌电活动 地表面 运动学 踝关节 表面相互作用
  • 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。

  • 标签: 诊断分析 不均匀的螺线雨乐队 垂直砍风 对流涡度向量
  • 简介:在一种紧急情况状况期间改进survivability,为飞机的一个算法强迫了登陆轨道计划被建议。方法集成计划进一个最佳的控制框架的损坏飞机建模和轨道。以便处理复杂飞机飞行动力学,解决的策略基于高斯pseudospetral方法(GPM)被介绍。A3-DOF考虑风的非线性的集体点的模型被开发接近在损失以后的飞机飞行动力学推进。答案最小化强迫的登陆持续时间,关于翻译改变的动力学,飞行信封限制和运作的安全要求的限制。GPM被用来变换计划问题到一个非线性的编程问题(NLP)的轨道,它被顺序的二次的编程算法解决。模拟结果证明建议算法能在事件产生最小时间的强迫的登陆轨道发动机外面与高效率和精确。

  • 标签: 轨迹规划 飞机 迫降 序列二次规划算法 高斯 非线性规划问题
  • 简介:Background:Artificialturfisconsideredafeasibleglobalalternativetonaturalturfbymanysportsgoverningbodies.Consequently,itsabilitytoprovideasafeandconsistentplayingsurfaceregardlessofclimatebecomesessential.Theaimsofthisstudyweretodeterminetheeffectsofartificialsurfacetemperatureon:(1)mechanicalpropertiesoftheturfand(2)thekinematicsofaturf-sportrelatedmovement.Methods:Twoidenticalartificialturfpitchesweretested:onewithacoldsurfacetemperature(1.8°C–2.4°C)andonewithawarmsurfacetemperature(14.5°C–15.2°C).Mechanicaltestingwasperformedtomeasurethesurfaceproperties.Fouramateursoccerplayersperformedahurdlejumptosprintaccelerationmovement,withdata(contacttime,steplengthandhip,kneeandanklekinematics)collectedusingCODASport(200Hz).Results:Thetemperaturedifferencehadasignificantinfluenceonthemechanicalpropertiesoftheartificialturf,includingforceabsorption,energyrestitution,rotationalresistance,andtheheightwheretheheadinjurycriterionwasmet.Bothsteplength(p=0.008)andcontacttime(p=0.002)oftheinitialstepafterthelandingweresignificantlylongeronthewarmsurface.Inaddition,significantrangeofmotionandjointangularvelocitydifferenceswerefound.Conclusion:Thesefindingshighlightdifferentdemandsplacedonplayersduetothesurfacetemperatureandsuggestaneedforcoaches,practitioners,andsportsgoverningbodiestobeawareofthesedifferences.

  • 标签: Artificial TURF BIOMECHANICS RUGBY SOCCER Temperature
  • 简介:为了描述创造登陆的一种新奇技术,在trabecular网状组织以内脱衣指导trabecular微绕过stent(iStent)在经历了phacoemulsification.METHODSThirty的病人的培植--从从2014年5月在phacoemulsification以后经历了iStent培植到2015年2月的30个病人的四只眼睛在我们的回顾的学习被包括。所有iStents经由登陆长带技术被植入。A25计量器microvitreoretinal片被用来切分trabecular网状组织到不到1钟小时,有效地创造登陆脱衣。iStent棉棍沿着登陆长带被压然后stent被释放进34与iStent培植看的trabecularmeshwork.RESULTSOf,(79.4%)27看有的主要开角度的绿内障,(17.6%)6看有的pseudoexfoliation绿内障,并且(2.9%)1看有的眼睛的高血压。在6月的后续(n=17),低血压患者药的吝啬的数字从2.2减少了

  • 标签: iStent trabecular 微绕过 stent microinvasive 绿内障外科 绿内障 trabecular 网状组织
  • 简介:<正>Purpose:Thepurposeofthisstudywastoexamineeffectsofasportversionofasemi-rigidanklebrace(ElementTM)andasoftanklebrace(ASO)onanklebiomechanicsandgroundreactionforces(GRFs)duringadroplandingactivityinsubjectswithchronicankleinstability(CADcomparedtohealthysubjectswithnohistoryofCAI.Methods:Tenhealthysubjectsand10subjectswhohadmultipleanklesprainsparticipatedinthestudyasthecontrolandunstablesubjects,respectively.TheCAIsubjectswereage,bodymassindexandgendermatchedwiththecontrolsubjects.Thearchindexandanklefunctionsofthesubjectsweremeasuredinasubjectscreeningsession.Duringthebiomechanicaltestsession,participantsperformedfivetrialsofdroplandingfrom0.6m,wearingnobrace(NB).Element?braceandASObrace.Simultaneousrecordingofthree-dimensionalkinematic(240Hz)andGRF(1200Hz)datawereperformed.Results:TheCAIsubjectshadloweranklefunctionalsurveyscores.ThearchindexanddeformityresultsshowedgreaterarchdeformityofElementTMagainstastaticloadthaninNBandASOduetogreaterinitialarchpositionheldbythebrace.CAIparticipantshadgreatereversionvelocitythanhealthycontrols.TheASObracereducedthefirstpeakverticalGRFwhereasElementTMincreased2ndpeakverticalGRF.ElementTMbracereducedeversionrangeofmotion(ROM)andpeakeversionvelocitycomparedtoNBandASO.Inaddition,ElementTMreduceddorsiflexionROMandincreasedpeakplantarflexionmomentcomparedtoNBandASO.Conclusion:Resultsofstaticarchmeasurementsanddynamicanklemotionsuggestthattherestrictionsofferedbybothbracesareinpartduetomoredorsiflexedanklepositionsatcontact,andhigherinitialarchpositionandstifferankleforElementTM.

  • 标签: Drop LANDING Lateral ANKLE SPRAIN Recurrent
  • 简介:TheNCEP/NCARreanalysis,JapanMeteorologicalAgency(JMA)tropicalcyclonetracksandintensivesurfaceobservationsareusedtodiagnosethefeaturesofmoisturetransportoftropicalstormBilis(No.0604),whichissimulatedbytheWRF(weatherresearchandforecasting)mesoscalenumericalmodel.ItisshownthattheBiliswaslinkedwiththemoisturechannelinthelowerlatitudesafteritslanding.Meanwhile,thecross-equatorialflowsover80°-100°EandSomaliwereactiveandbroughtabundantwatervaporintothetropicalstorm,facilitatingthemaintenanceofthelandingstormwithintensifiedheavyrainfallalongitspath.ThesimulationsuggestedthatthedecreasedwatervaporfromlowerlatitudespreventsthemaintenanceofBilisandthedevelopmentofrainfall.Whilethecross-equatorialflowsover80°-100°EandSomaliwereinfavorofkeepingthecycloniccirculationoverland.IfthemoisturesupplyfromtheSomalijetstreamwasreduced,thestrengthandareaofheavyrainfallintropicalcyclonewouldberemarkablyweakened.Consequently,thedecreasedwatervaporfromlowerlatitudescanremarkablysuppressthedeepconvectionintropicalstorm,thenBiliswasdampedwithoutthepersistentenergysupportandtherainfallwasdiminishedaccordingly.

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