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25 个结果
  • 简介:Theeffectsofhighermodesandtorsionhaveasignificantimpactontheseismicresponsesofasymmetric-plantallbuildings.Aconsecutivemodalpushover(CMP)procedureisoneofthepushovermethodsthathavebeendevelopedtoconsidertheseeffects.Theaimofthispaperistomodifythe(CMP)analysisproceduretoestimatetheseismicdemandsofone-wayasymmetric-plantallbuildingswithdualsystems.Ananalysisof10-,15-and20-storyasymmetric-planbuildingsiscarriedout,andtheresultsfromthemodifiedconsecutivemodalpushover(MCMP)procedurearecomparedwiththoseobtainedfromthemodalpushoveranalysis(MPA)procedureandthenonlineartimehistoryanalysis(NLTHA).TheMCMPestimatesoftheseismicdemandsofone-wayasymmetric-planbuildingsdemonstrateareasonableaccuracy,comparedtotheresultsobtainedfromtheNLTHA.Furthermore,theaccuracyoftheMCMPprocedureinthepredictionofplastichingerotationsisbetterthantheMPAprocedure.ThenewpushoverprocedureisalsomoreaccuratethantheFEMAloaddistributionandtheMPAprocedure.

  • 标签: MODIFIED consecutive modal PUSHOVER SEISMIC DEMANDS
  • 简介:Ananalyticalstudyispresentedonthemodaldispersioncharacteristics,groupvelocity,andeffectivegroup,aswellasthephaseindexofaternaryonedimensionalplasmaphotoniccrystalforanobliquelyincidentelectromagneticwaveconsideringtheeffectofcollisionsinplasmalayers.Thedispersionrelationisderivedbyusingthetransfermatrixmethodandtheboundaryconditionsbasedonelectromagnetictheory.Thedispersioncurvesareplottedforboththenormalphotonicbandgapstructureandtheabsorptionphotonicbandgapstructure.Itisfoundthattheincreaseintheangleofincidenceshiftsthephotonicbandgaptowardhigherfrequencies.Also,thecutofffrequencyisindependentofcollisions.

  • 标签: 倾斜入射 等离子体 电磁波 碰撞 晶体性能 一维
  • 简介:摘要目的探讨固定式Twim-Block矫治器治疗安氏Ⅱ类错牙合患者在牙性、骨性所发生的变化,并掌握这种新型矫治器的临床操作。方法选择20例安氏Ⅱ类错牙合患者,以下颌后缩为主,年龄在12~15岁之间,恒牙颌,采用固定式Twim-Block矫治器进行功能矫治,对矫治前后的模型、X光片进行头影测量分析。结果①头影测量显示SNB、L1-NB、L1-MP、ANS-Me、N-Me增大,ANB、U1-SN、U1-NA减小,并有统计学差异(P<0.05)②模型测量分析磨牙关系由Ⅱ类变Ⅰ类或偏Ⅲ类;前牙覆盖有8.95mm减至2.86mm。结论固定式Twim-Block矫治器具有不依赖患者配合的特点,疗效显著,全天候戴用可缩短疗程,扩大适应征范围;制作简单,值得在临床推广。

  • 标签: 固定式Twim-Block矫治器 下颌后缩 头影测量