简介：<正>Peopleenjoytakingtrips.Butwhatarethereasonstheyleavehome?Onereasonisforeducation.Peopletravelbecausetheywanttobroadentheirhorizonstolearnabouto

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简介：Howwillyouknowyoucansucceedatsomethingifyoudon’tgiveitatry?如果你不尝试又怎么能知道你会成功?Howwillyouknowyoucandragyourselfoutofthedepthsofyourdespairifyoudon’ttry?如果你不尝试又怎么能知道你能把自己从绝望的深渊中解脱出来?

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简介：IfyoureallywanttolearnEng-lish,youmustLearnbyDoing!Evenifyoucannottravelrightnow,youcanuseyourimaginationtoexperi-enceEnglish.Themoreyouimagine,themoreyouwillremember.MakeapictureinyourmindtomaththewordsofLiuFayeandJerry.Ifyoucan"feel"theirEnglish"inyourbones~I",youwillimproveveryquickly.Goodluck!

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简介：LookingfromChina’sneighboringenvironment,theAmericafactorisundoubtedlythemostimportantfactorinanalyzingChina’sneighboringsecurity.SpeakingofU.S.influenceonChina’sneighboringsecurity,somescholarstendtobelievethattheunfavorablefactorsplayadominantrole.Thisconclusioncomesfromthe"newmoonshapeencirclement"alreadyexistingsincetheColdWarinAmerica,

简介：AftertheSeptember11events,theinternationalpatternandgreatpowerrelationshavereadjusted.Theimportanceofnon-traditionalsecurityfactorsininternationalpoliticsriserapidly.Thehomelandsecurityissuethatvarioussovereignstatesareconfrontinghasbecomeprominent.Thesechangesre-challengethetraditionalsecurityconcept.

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简介：Ididn'trealizethebeautyofTibetthefirsttimeIwentthere30yearsago.But,whilevisitingTibetinrecentyears,Iwasmovedtotearsasthemarvelousplateausceneryunfoldedbeforemyeyes.

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简介：AsymmetryoftheWeiheBasinisdiscussedinthepaper,andalsothemastercontrolfault,secondarycontrolfaultofasymmetricbasinisproposedinthepaper.TheasymmetryoftheWeiheBasinisexpressedasfollows:(1)itsshapeofthecrosssectionsisasymmetrical;(2)thetectonicactivityofthesouthernmarginfaultandthenorthernmarginoneisapparentlydifferent;(3)itsdeeptectonicsisasymmetrical.Finally,weusetheWeiheBasinasanexampletoestablisha"cantilever-beam"modelforcalculations.Theresultsshowthat:(1)flexureleadstostressaccumulationandformingextensionalfractures;(2)fracturesslopesteeplytowardsthefreeend;(3)whenthelengthofbeambecomeslonger,itispossiblethatnewextensionalfractureswilloccurinthefixedend.

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简介：Duetocentrifugalforcesinabendsecondarycurrentsperpendiculartothemainflowaregenerated.Becausetheycanbethereasonforimportantbedformingprocessessuchasmeanderingtheyhavetobetakenintoaccountinmorphodynamicsimulations.Theirinfluenceonthebedshearstressisproportionaltotheratioofwaterdepthandcurveradius.Thelatteroneisacurveparameterandisnotdefinedin2Ddigitalterrainmodels.Thispaperpresentsanewformulationforthebedshearstresswhichtakesintoaccounttheinfluenceofsecondarycurrentsindepthaveragedsimulationswithoutusingthecurveradius.ThenewformulationisappliedtoamorphodynamicmodeloftheWeserestuarylocatedinNorthernGermany.Itscapabilitytosimulatethedeflectionofthebedshearstressinbendsisshown.BecauseofthesmoothnessofthecurvesintheWesernosignificantdifferencesinthebedevolutioncanbeseeninthiscase.

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