简介：Observationsofaquasi-90-dayoscillationinthemesosphereandlowerthermosphere(MLT)regionfromApril2011toDecember2014arepresentedinthisstudy.Thereisclearevidenceofaquasi-90-dayoscillationintemperaturesobtainedfromtheKunmingmeteorradar(25.6°N,103.8°E)andSoundingoftheAtmosphereusingBroadbandEmissionRadiometry(SABER),aswellasinwindobservedbytheKunmingmeteorradar.Thequasi-90-dayoscillationappearstobeaprominentfeatureinthetemperaturesandmeridionalwindtidesandpresentsquiteregularcyclesthatoccurapproximatelytwiceperyear.Theamplitudesandphasesofthequasi-90-dayoscillationintheSABERtemperatureshowafeaturesimilartothatofupward-propagateddiurnaltides,whichhaveaverticalwavelengthof~20kmabove70km.Intheloweratmosphere,asimilar90-dayvariabilityispresentedinthesurfacelatentheatfluxandcorrelateswiththetemperatureintheMLTregion.Similartothequasi-90-dayoscillationintemperature,a90-dayvariabilityofozone(O3)isalsopresentintheMLTregionandisconsideredtobedrivenbyasimilarvariabilityintheupwardly-propagateddiurnaltidesgeneratedintheloweratmosphere.Moreover,the90-dayvariabilityintheabsorptionofultraviolet(UV)radiationbydaytimeO3intheMLTregionisaninsitusourceofthequasi-90-dayoscillationintheMLTtemperature.

简介：Basedonresearchesmadebytheauthorinrecentyears,discussionismadeofthequasi-40-dayoscillation(QDO)natureanditscharacteristicpropagation,withemphasisontheSouthernHemispheremill-latitudequasi-periodiccoldairforcingonthetropicalatmospherequasi-40-dayoscillationalongwithitseffectupontheNorthernHemispheresummermonsoon.Itisproposedthattheinteractionbetween,orlateralcouplingof,meridionalcirculationsystemsmayserveasthemechanismoftheoscillationpropagationinameridionaldirection.

简介：12月岁末2008年最后的测试在西班牙的赫雷斯进行。在3天的测试中,我参加了第2天和第3天的测试。据说为这个冬季测试提供餐饮服务的工作人员以前曾服务过丰田车队，每天都有意大利面配肉和蔬菜套餐。不过这次测试中，帐篷内还准备了寿司手卷这样的日本料理。味道方面由于米的种类不同所以很难和日本的一样。但车队工作人员都觉得很好吃。我也吃了几个，不过我个人还是觉得意大利面和英国料理更好吃。

简介：<正>PeopleintheUnitedStateshonortheirparentswithtwospecialdays:Mother’sDay,onthesecond

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简介：<正>在中国,每当谈到MayDay“五一”,我们马上会想到“五一国际劳动节”。而近几年,谈到“五一”我们就会想到与之相连的“五一”长假。对全球来说,MayDay也确实是国际劳动

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简介：圣诞节到了!孩子们个个都期待欣赏雪景和收到礼物。聆听这首歌，然后试试跟着音乐一起唱吧!

简介：ThefirstThanksgivingDaycelebrationinAmericawasinthefallof1621.Thecolonistsgatheredtogivethanksforthesummer'sharvest.Theyhadstruggledthroughahardwinter.Manypeoplehaddied.Thecoldwasterrible.Therehadnotbeenmuchfoodthatfirstwinter.

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简介：今天，爸爸给我讲了感恩节的由来。这个节日最早是美洲移民为了感谢和纪念印第安人的帮助而设定的，现今的主要内容就是感恩和吃火鸡。

简介：Itisafineday.Thesunisinthesky.MrGreenandhisfamilyareinthepark.MrandMrsGreenaresittingunderthetreeandlookingattheirchildren.Theirdaughter,Annisflyingakite.

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简介：<正>INTHEMORNING梦中隐约听到"七点半了!"七点半了?七点半!在我完全清醒之前,就已知道过会儿将执行何种的超音速动作。而在这北国的冬日里,钻出被窝所需的勇气,不亚于一个冬泳者涉入"冰水混合物"之前所要做的心理准备……我无视自己严重的胃病,毅然放弃了早餐。但接着却遇上了隐形眼镜的"终极问题"——

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