简介:为了更真实地反映拥堵交通网络实际情况,考虑到交叉口转向延误和路段容量约束对交通分配模型的影响,首先构建了带转向延误和路段容量双约束下的用户均衡模型,利用Karush-Kuhn-Tucker条件证明其等价性;其次,通过改进的最短路算法,利用ProjectionGradient算法作为内循环、增强拉格朗日乘子法作为外循环求解该模型.最后,利用算例路网证明该算法的可行性,对比初始状态、管控措施及双约束状态下的均衡网络流交通分配结果,发现得到路径解的同时能清晰地知道某一路段或路径交通流量转移情况,该模型通过流量转移为交通管控措施提供决策依据,进而有效地缓解交通拥堵.
简介:Inthenormaloperationcondition,aconventionalsquare-rootcubatureKalmanfilter(SRCKF)givessufficientlygoodestimationresults.However,ifthemeasurementsarenotreliable,theSRCKFmaygiveinaccurateresultsanddivergesbytime.ThisstudyintroducesanadaptiveSRCKFalgorithmwiththefiltergaincorrectionforthecaseofmeasurementmalfunctions.Byproposingaswitchingcriterion,anoptimalfilterisselectedfromtheadaptiveandconventionalSRCKFaccordingtothemeasurementquality.Asubsystemsoftfaultdetectionalgorithmisbuiltwiththefilterresidual.Utilizingaclearsubsystemfaultcoefficient,thefaultysubsystemisisolatedasaresultofthesystemreconstruction.Inordertoimprovetheperformanceofthemulti-sensorsystem,ahybridfusionalgorithmispresentedbasedontheadaptiveSRCKF.Thestateanderrorcovariancematrixarealsopredictedbythepriorifusionestimates,andareupdatedbythepredictedandestimatedinformationofsubsystems.Theproposedalgorithmswereappliedtothevesseldynamicpositioningsystemsimulation.TheywerecomparedwithnormalSRCKFandlocalestimationweightedfusionalgorithm.ThesimulationresultsshowthatthepresentedadaptiveSRCKFimprovestherobustnessofsubsystemfiltering,andthehybridfusionalgorithmhasthebetterperformance.Thesimulationverifiestheeffectivenessoftheproposedalgorithms.
简介:分析了几种数字梳状滤波器在进行视频信号的亮、色分离时的优、缺点。针对现有的1D、2D数字梳状滤波器的局限性,通过引入图像前后场内容的相关性,实现了基于图像内容的BD运动自适应数字梳状滤波器的算法。通过与实际图像比对,证明了采用这种处理方法的滤波器能够达到非常好的亮、色分离效果。