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145 个结果
  • 简介:Wakestructuresandvortexinducedvibration(VIV)ofaspring-supportedwide-D-sectioncylinderwereexperimentallyinvestigatedusinganX-wire,anovelphase-lockedparticleimagevelocimetry(PIV),andanaccelerationsensoratalowspeedwindtunnel.Comparedwiththefixedcase,the2P(twopair)vortexmodeasdefinedbyGovardhanandWilliamson(2000)ratherthanS(singlevortex)modeexistsinthewake.Thevelocitydeficitbehindthecylinderismuchlargerthanthatoffixedcase.Themeandragcoefficientincreasesfrom1.42forthefixedcaseto1.64forthevibratingcase.TheReynoldsstresspresentsevendistributionandsmallwithincreaseddistanceofX/D=-2toX/D=-10.Thepowerspectradensitybasedonacceleratorandhotwiredatapresentsahighlightidentical.Itshowsthatafterastronginteractionthecylindervibrationandthevortexsheddingcometoastablestate.Thevortexsheddingistotallylockedonandcontrolledbythecylindervibration.

  • 标签: 涡激振动 实验 加速度传感器 粒子图像测速仪 横流 功率谱密度
  • 简介:ThisessayistalkaboutThesignificanceofcross-culturecommunicationinglobalmodernsociety.Itwillexpoundthenecessityofcross-culturalcommunicationfortheglobalmodernsociety,whichincludesexplainhowthecross-culturecommunicationworksintheglobalmodernsociety.

  • 标签: CROSS-CULTURE COMMUNICATION GLOBAL MODERN SOCIETY NECESSITY
  • 简介:<正>ThedevelopmentoffriendlypartnershipfullymeetstheinterestsofbothRussiaandChina.VladimirV.PutinItshouldbementionedthattheprosperityofRussia-Chinarelationsisexpectednotonlybecauseofcommonhistory,politicalandeconomicalinterestsbutalsobecauseofsharingmanykilometersofcommonborder.Apparently,

  • 标签: Russia Vladimir POLITICAL BORDER friendly PROSPERITY
  • 简介:trifluoromethyl的极其快的准备第三级的白酒在溶剂下面从甲基酉同类和trifluoromethyl酉同类被完成了由生气丁间醇醛反应的免费条件。反应被在周围的温度磨方法在高收益(多达95%)给-trifluoromethyl--hydroxyl酉同类面对普通的无机的底完成。

  • 标签: 羟醛缩合反应 无溶剂合成 叔醇 无溶剂条件 快速制备 甲基酮
  • 简介:Thispaperexploresthebasicframeworkforcross-culturaldialogueonhumanrights.Suchdialogueimplicatesdifferingunderstandingsofthecontentofhumanrightsaswellasdifferinginterpretationoftheconceptofhumanrightsitself.Thechallengesconfrontingtheuniversalityofhumanrightsarguablystemfrompeople’sfearofradicalindividualism,secularfundamentalismandpoliticalradicalism.Whiletheuniversalityofhumanrightsshouldnotbedenied,cognizancemustbetakenaswellofthegapbetweentheoryandpracticeduringtherealizationofthoserightsandtheselectivitypertainingtosuchrealization.Dogmatismanduncompromisingideologicalstancesisanobstacletodialoguesandcross-culturalexchangesonhumanrights.

  • 标签: HUMAN RIGHTS UNIVERSALITY of HUMAN RIGHTS
  • 简介:Thisstudyproposesanewidentificationalgorithmabouttheadmittancefunction,whichcanestimatethefullsetofsixaerodynamicadmittancefunctionsconsideringcrosspowerspectraldensityfunctionsabouttheforcesandtheturbulencecomponents.ThemethodwasfirstnumericallyvalidatedthroughMonteCarlosimulations,andthenadoptedtoestimatetheaerodynamicadmittanceofastreamlinedbridgedeck.Theidentificationmethodwasfurthervalidatedthroughacomparisonbetweenthenumericalcalculationandwindtunneltestsonamovingbridgesection.

  • 标签: aerodynamic ADMITTANCE FUNCTION streamlined box bridge
  • 简介:<正>Editor’snote:ChineseAssociationforInternationalUnderstanding(CAFIU)establishedrelationswithgovernmentofHiroshimaPrefectureofJapanin1999.Twoprograms,namelyOverseasTechnologyResearchWorkersandShort-timeTrainingCourseforOverseasJapaneseTeacherswerelaunchedin2000.EachyearCAFIUrecommendsoneJapaneseteacherforatwo-month

  • 标签: Japanese Training PROGRAMS GRAMMAR PRONUNCIATION EDUCATIONAL
  • 简介:Toestablishthemechanismofsurfacechangeinacontinuouspolishingsystem,anidealmathematicalmodelisbuiltbasedonWinkler’shypothesisandthePrestonequation.Thebasicfeaturesofthemodelarethechangeratesinthesurfacepeak–valley(PV)valuesoftheworkpiece,conditioningdiskandpitchlap,ratherthanthespecificsurfaceshapes.Inaddition,anequilibriumstateexistsinthesystem,indicatingthatthesurfacechangeratesareallzero.Underequilibrium,thesurfaceofthelapcouldremainflat,anditisinsensitivetothesurfaceerroroftheworkpiece.Thesecharacteristicslaythetheoreticalfoundationsforhigh-efficiencyandhigh-precisionpolishing.Themethodstoobtainanequilibriumstatewithflatsurfacesarethenproposedandconfirmedexperimentally.High-precisionsurfacesbetterthanλ/10(λ=632.8nm)areconsistentlyproducedexperimentally.

  • 标签: CONTINUOUS POLISHING EQUILIBRIUM STATE HIGH accura
  • 简介:MostscholarsworkingontheeconomydevelopmentinTibet,especiallythehusbandrymentionedthe"reluctanceslaughterandsell"phenomenonoffarmer(herdsman)andallagreedthatitisanimportantreasonforobstructingthecomeoutrateoflivestockinTibetandcausingundevelopedcommodityeconomyandgrasslandoverload.

  • 标签: 销售 屠宰 藏族 经济发展 商品经济 学者
  • 简介:Heartfailure(HF)isacomplexclinicalsyndromethatresultsfromanystructuralorfunctionalimpairmentofventricularfillingorejectionofblood.HFisoneofthemostimportantandsevereendstagesofmanycardiovasculardiseases.EpidemiologicalstudiesofHFhavefocusedmainlyontheprevalence,incidence,mortality,fatality,anddistributionandtemporaltrendsoftheseindicatorsamongdifferentpopulations.ThisreviewhighlightsimportantepidemiologicalstudiesofHFinChina.

  • 标签: HEART FAILURE CARDIOVASCULAR DISEASES EPIDEMIOLOGICAL study
  • 简介:·AIM:Toevaluateandcomparetheefficacyandstabilityofintrastromalcornealringsegment(ICRs)implantationwithcross-linking(CXL)usingdifferentsequenceandtiming.·METHODS:Inthissingleretrospectivestudy,86keratoconiceyessubjectedtheICRsimplantation.Weanalyzedonly41eyesthathadcompletefollow-ups.Theyweredividedintothreegroups:ICRsimplantationwasappliedonly(groupnormal),ICRsfirstfollowedbyCXLimmediately(groupCXL-S),CXLfirstfollowedbyICRslongafter(groupCXL-B).Thevisualacuity,refractiveresults,keratometrywerecomparedpreoperativelyand1ypostoperatively.Theirdifferencesamongthethreegroupswerealsoanalyzed.·RESULTS:Groupnormalcomprised25eyes,groupCXL-S8eyes,andgroupCXL-B8eyes.Therewereimprovementsinthemeanuncorrecteddistancevisualacuity(UDVA)andthemeancorrecteddistancevisualacuity(CDVA)comparedpreoperativelyand1ypostoperatively[UDVA:0.31(P=0.030)logarithmicminimumangleofresolution(logMAR)groupnormal,0.4(P=0.020)groupCXL-S,0.45(P=0.001)groupCXL-B;CDVA:0.21logMAR(P=0.013)groupnormal,0.30(P=0.036)groupCXL-S;0.26(P=0.000)groupCXL-B].Therefractiveandtopographicoutcomesalsoshowedimprovements.Intermsofcomparisonsamongthethreegroups,allthePvalueswereabove0.05,showingnosignificantdifference.ButonlygroupCXL-BhadimprovementinUDVAandCDVAforallthepatients.·CONCLUSION:Withsafetyandgoodvisualoutcomes,ICRsimplantationisaviablealternativeforkeratoconus.Nosignificantdifferencewasfoundamongthesethreegroups.

  • 标签: KERATOCONUS intrastromal CORNEAL RING SEGMENT cross-linking
  • 简介:Inthispaper,thehydrodynamiccharacteristicsofwaterflowinChaohuLakearestudiedbyusingthefinitevolumecoastaloceanmodel(FVCOM),whichisverifiedbytheobserveddata.Thetypicalflowfieldandthe3-Dflowstructureareobtainedforthelake.Theflowfieldsunderextremeconditionsareanalyzedtoprovideaprospectiveknowledgeofthewaterexchangeandthetransportprocess.Theinfluenceofthewindontheflowisdeterminedbythecrossspectrummethod.Theresultsshowthatthewind-drivenflowdominatesmostareaofthelake.Underprevailingwindsinsummerandwinter,thewaterflowstowardsthedownwindsideattheupperlayerwhiletowardstheupwindsideatthelowerlayerinmostareaexceptthataroundtheChaohuSluice.Theextremewindspeedisnotfavorableforthewaterexchangewhilethesluice’sreleasingwateracceleratestheprocess.Thewatervelocityinthelakeiscloselyrelatedwiththewindspeed.

  • 标签: 水动力过程 数值研究 巢湖 流场结构 水动力特性 海洋模式