简介:新一代911TurboS延续了这一代911车型引人注目的重要设计特征,在熟悉的轮廓之下、911TurboS搭载了拥有动态照明升级系统(简称PDLS+)的全新LED头灯组,会依据转向角度与车速,来决定头灯向弯道内侧照明的角度,可在弯道中提供更充足的照明.带侧导气片的新前端造型以及带双嵌条、精心设计的修长LED前大灯突出了前端的宽度,并且在中央进气口中还增加了隔板.在侧面,这款高性能跑车配备了全新的20英寸轮毂.与911Carrera车系相似,带四点式制动灯和光环照明的立体尾灯组十分引人瞩目.后端排气系统的排气口以及双尾管经过重新设计.后盖格栅也采用全新设计,右侧和左侧部分带有纵向格栅,中间是一个独立的护罩,用于优化发动机的空气导流.为了对应强劲的动力输出,跟Carrera4相比,911TurboS的车尾加宽了28毫米,让原本就已经够销魂的钣件线条,再次变得更加丰腴.
简介:Analgorithmforcomputingthe3-Doscillatingflowfieldofthebaldepassageunderthetorsionalvibrationoftherotorisappliedtoanalyzethestabilityinturbomachines.TheinducedflowfieldrespondingtobladevibrationiscomputedbyOscillatingFluidMechanicsMethodandparametricPolynomialMethod.Aftergettingthesolutionoftheunsteadyflowfield,theworkdonebytheunsteayaerodynamicforceactingonthebladecanbeobtained.Thenegativeorpositiveworkisthecriterionoftheaeroelasticstability.Numericalresultsindicatethatthereareinstabilitiesofthetorsionalvibrationinsomefrequencybands.
简介:随着Turbo码编译码结构及译码算法的不断优化和改进,Turbo码已被确定为第三代移动通信IMT-2000的编码方案。通过使用MATLAB软件仿真实现了Turbo码编码,提高了对其高效优质的编码效率的认识。
简介:Aconstructionmethodbasedonthep-planetodesignhigh-girthquasi-cycliclow-densityparity-check(QC-LDPC)codesisproposed.Firstlythegoodpointsineverylineofthep-planecanbeascertainedthroughfilteringthebadpoints,becausethedesignedparity-checkmatrixesusingthesepointshavetheshortcyclesinTannergraphofcodes.Thenoneofthebestpointsfromtheresidualgoodpointsofeverylineinthep-planewillbefound,respectively.Theoptimalpointisalsosingledoutaccordingtothebiterrorrate(BER)performanceoftheQC-LDPCcodesatlast.ExplicitnecessaryandsufficientconditionsfortheQC-LDPCcodestohavenoshortcyclesarepresentedwhichareinfavorofremovingthebadpointsinthep-plane.Sincepreventingtheshortcyclesalsopreventsthesmallstoppingsets,theproposedconstructionmethodalsoleadstoQC-LDPCcodeswithahigherstoppingdistance.
简介:InordertoimprovethevideotransmissionperformanceinMultiple-InputMultiple-OutputOrthogonalFrequencyDivisionMultiplexing(MIMO-OFDM)system,anewscheme,whichintegratesMultipleDescriptionCoding(MDC),LowDensityParityCheck(LDPC)codingandhybridspacetimecoding,isproposedinthisletter.Inparticular,ahybridspacetimecodingalgorithmiscombinedwithLDPCcodestoperformUnequalErrorProtection(UEP)ofMDCencodedvideostreams.ComparingwiththeUEPtransmissionwithonlyLDPCcodes,theproposedschemeachievesmorethan1dBgainintermsofSignaltoNoiseRatio(SNR)whenthePeakSignaltoNoiseRatio(PSNR)ofreconstructedvideoisabove30dB.
简介:摘要:错题微课 可以解决我们的教学中的 难题。它不仅可以弥补学生学习中的薄弱环节,还能 有效地利用学生分散的时间。二维码的便利性使原来固定时间 和固定地点的传统学习方式演化成了 一种随时随地广泛参与的在线学习。结合二维码 技术的发展,可以将 实现误题资源的广泛共享。