简介:摘要传统Buck-Boost主拓扑电路在电压转换过程中易出现,电压变换稳定系数低输出纹波电流大杂波发生系数大等缺点;针对传统Buck-Boost的相关缺陷,本文提出一种组合式Buck-Boost主拓扑电路,并基于SaberDesigner仿真软件展开性能验证。
简介:论文介绍了在真实能谱衰减环境中,提出一套对核素进行识别学习算法的流程。采用SVD特征抽取对能谱数据降维,提取到能谱特征向量,在形成的特征向量数据集上,训练决策树分类器,进而通过AdaBoost集成学习算法对多轮的决策树算法的训练结果进行融合,使用K轮类别投票法结合策略,构建一个结果更为接近标签值的假设函数算法模型,解决了探测器检测的能量信息具有局部特征、存在重叠峰值导致核素判别出现错失误判的问题,提高核素识别率。
简介:Anovelcontrolschemeispresentedbyusingsliding-modecontrolforboostconverteroperatingincontinuousconductionmode(CCM).Althoughthenon-idealswitchingconditionandphysicalconstraintofthecontrolareconsideredonthebaseofequivalentcontrol,theschemeisstillsimple.Bymodifyingthesliding-modcerrorsineachswitchingperiod,thesteady-stateerrorsandchatteringcanbesubstantiallyreduced.Simulationresultsconfirmthetheoreticalanalysisandshowtheimprovementoftheconverter’sstart-upbehaviorandlowsensitivitytoexternalperturbation.
简介:Consideringtheproblemofmultipleballisticmissilestrackingofboost-phaseballisticmissiledefense,aboost-phasetrackingalgorithmbasedonmultiplehypothesestracking(MHT)conceptisproposed.Thispaperfocusesonthetrackingalgorithmforhypothesisgeneration,hypothesisprobabilitycalculation,hypothesesreductionandpruningandothersectors.Fromanengineeringpointofview,atechniquecalledthelinearassignmentproblem(LAP)usedintheimplementationofM-bestfeasiblehypothesesgeneration,thenumberofthehypothesesisrelativelysmallcomparedwiththetotalnumberthatmayexistineachscan,alsotheiV-scanbackpruningisused,thealgorithm’sefficiencyandpracticalityhavebeenimproved.MonteCarlosimulationresultsshowthattheproposedalgorithmcantracktheboostphaseofmultipleballisticmissilesandithasagoodtrackingperformancecomparedwithjointprobabilitydataassociation(JPDA).
简介:Thezero-voltagequasi-resonantboostswitchingDC-DCconverterhasbeeninves-tigatedbyusingthetimeaveragingequivalentcircuitapproachofperiodicallyswitchinglinearnetworks.TheDCsteadystateandACsmallsignalcharacteristicsoftheconverterarealsogiven.
简介:风廓线雷达大气湍流回波信号的识别常受到间歇性杂波的严重干扰。为了能够有效抑制并消除该类杂波,本文提出了基于线性时-频变换的间歇性杂波消除抑制算法。该算法采用具有线性时-频分布特性的短时傅里叶变换,获取雷达回波中杂波成分的调制频率参数,然后估计出相应分数阶傅里叶变换(FRFT)的最优阶数,最后再利用FRFT检测出杂波并对其抑制,通过信号重构回到时域,从而获取有效回波信号频谱。本文提出的方法与常规的FRFT最优阶数扫描法相比,将杂波检测二维搜索问题简化为一维峰值搜索问题,计算量大大降低。理论及计算机仿真表明,该方法效果明显,具有良好的工程应用前景。