简介：来自爱尔兰的演唱组合“西城男孩”自出道以来就受到歌迷们的青睐，是当今最具人气的组合之一。他们从1998年的“SmashHitsAwards”最佳新人奖得主，到“Mylove”“FlyingWithourWings”,“IfILetYouGo”等佳作的流传，现在已成为红遍全球的流行乐坛巨星。

简介：在年初的卡塔尔车展当中，大众除了展出一些刻意针对当地消费习惯的概念车之外．还推出了这部名为XLI的节能概念车，虽然在全世界石油最不匮乏的地区发表节能概念车有些奇怪，但这部车确实达成了当年度耶博士所发下的豪语——推出每行驶100公里只需1升汽油天使般的车辆。

简介：Thepotentialforharvestingenergyfromaflexibledeltawingusingapiezoelectricbimorphisexperimentallyinvestigated.Differentconfigurationsoftheproposedharvestingsystemweretestedinawindtunneloverabroadrangeofairspeeds.Inadditiontoevaluatingthelevelofharvestedpower,ananalysisisperformedtoextractcriticalaspectsfortherelationbetweenspeed,flexibility,geometryandthepotentialpowerthatcanbeharvestedfromaclamped,cantileveredflexibledeltawingatlowanglesofattackandlowspeeds.Thisanalysisprovidesaninsightintoparametersthatimpactenergyharvestingfromflexiblemembranesorelements.

简介：

简介：Theeffectsofcorrugationandwingplanform(shapeandaspectratio)ontheaerodynamicforceproductionofmodelinsectwingsinsweeping(rotatingafteraninitialstart)motionatReynoldsnumber200and3500atangleofattack40°areinvestigated,usingthemethodofcomputationalfluiddynamics.Arepresentativewingcorrugationisconsidered.Wing-shapeandaspectratio(AR)oftenrepresentativeinsectwingsareconsidered;theyarethewingsoffruitfly,cranefly,dronefly,hoverfly,ladybird,bumblebee,honeybee,lacewing(forewing),hawkmothanddragonfly(forewing),respectively(ARofthesewingsvariesgreatly,from2.84to5.45).Thefollowingfactsareshown.(1)Thecorrugatedandflat-platewingsproduceapproximatelythesameaerodynamicforces.Thisisbecauseforasweepingwingatlargeangleofattack,thelengthscaleofthecorrugationismuchsmallerthanthesizeoftheseparatedflowregionorthesizeoftheleadingedgevortex(LEV).(2)Thevariationinwingshapecanhaveconsiderableeffectsontheaerodynamicforce;butithasonlyminoreffectsontheforcecoefficientswhenthevelocityatr2(theradiusofthesecondmomentofwingarea)isusedasthereferencevelocity;i.e.theforcecoefficientsarealmostunaffectedbythevariationinwingshape.(3)TheeffectsofARareremarkablysmall:whenARincreasesfrom2.8to5.5,theforcecoefficientsvaryonlyslightly;flowfieldresultsshowthatwhenARisrelativelylarge,thepartoftheLEVontheouterpartofthewingsshedsduringthesweepingmotion.AsARisincreased,ononehand,theforcecoefficientswillbeincreasedduetothereductionof3-dimensionalfloweffects;ontheotherhand,theywillbedecreasedduetothesheddingofpanoftheLEV;thesetwoeffectsapproximatelycanceleachother,resultinginonlyminorchangeoftheforcecoefficients.

简介：

简介：

简介：染料注射和氢水泡可视化技术被用来在非苗条的三角洲翅膀上包括它的发展，故障和旋涡核心的空间地点调查双旋涡的结构。双旋涡的结构能受显著地影响，这被结束打扫角度和雷纳兹数字，并且仅仅在攻击的小角度产生了。在三角洲翅膀表面和根弦线上的外部旋涡核心的设计之间的角度与雷纳兹数字和攻击的角度没关系，但是与测试的模型的sweep角度有简单线性关系。

简介：