简介：美欧日作为世界上最大的三个发达经济体,尤其是在欧日自贸协定已经谈成的情况下,其自贸协定动向确实值得关注.但它们要联合组建自贸协定也存在重重困难,并非易事.今年7月17日,欧盟和日本在东京签署自由贸易协定,名为“欧日经济伙伴协定”（EU-JapanEconomicPartnershipAgreement）.

简介：在国际货运业务中,NVOCC（无船承运人）模式经过几十年的发展已经日趋成熟,传统货运代理企业的生存空间越来越小,货运代理企业NVOCC化已成大势所趋.只有从传统业务向全程物流链拓展,形成门到门的全程物流服务能力,才可能在激烈的市场竞争中脱颖而出,获得生存和发展的空间.

简介：Acomplianttowerismodeledasapartiallydry,partiallytapered,dampedTimoshenkobeamwiththesuperstructuremodeledasaneccentrictipmass,andanon-classicaldampedboundaryatthebase.Thefoundationismodeledasacombinationofalinearspringandatorsionalspring,alongwithparallellinearandtorsionaldampers(Kelvin-Voigtmodel).Thesuperstructureaddstothekineticenergyofthesystemwithoutaffectingthepotentialenergy,therebyreducingthenaturalfrequencies.Theweightofthesuperstructureactsasanaxialcompressiveloadonthebeam,reducingitsnaturalfrequenciesfurther.Theemptyspacefactorduetothetruss-typestructureofthetowerisincluded.Theeffectofsheardeformationandrotaryinertiaareincludedinthevibrationanalysis;withthenon-uniformbeammode-shapesbeingaweightedsumoftheuniformbeammode-shapessatisfyingtheendcondition.TheweightsareevaluatedbytheRayleigh-Ritz(RR)method,andverifiedusingfiniteelementmethod(FEM).Theweightofthesuperstructureactsasanaxialcompressiveloadonthebeam.Kelvin-Voigtmodelofstructuraldampingisincluded.Apartofthestructurebeingunderwater,thevirtualaddedinertiaisincludedtocalculatethewetnaturalfrequencies.Aparametricstudyisdoneforvariousmagnitudesoftipmassandvariouslevelsofsubmergence.ThecomputationalefficiencyandaccuracyoftheRayleigh-Ritzmethod,ascomparedtotheFEA,hasbeendemonstrated.Theadvantageofusingclosed-formtrialfunctionsisclearlyseenintheefficacyofcalculatingthevariousenergycomponentsintheRRmethod.