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夏巧生 《计算机与应用化学》2014,(1)
偏最小二乘算法(PLS)是常用的线性光谱建模方法。针对汽油在线调合中具有非线性特点的辛烷值、干点等属性应用PLS方法建立模型误差较大问题,本文提出了残差-递阶偏最小二乘的建模方法,该方法对已经提取成分后的自变量中剩余的信息再提取主成分,并将该主成分作为新的自变量参与回归建模。仿真验证结果表明:残差-递阶偏最小二乘方法建立的模型中验证集的样本数据误差均在正负0.2之间。残差-递阶偏最小二乘方法与偏最小二乘、递阶偏最小二乘叫-PLS)两种方法比较,残差-递阶偏最小二乘建立的模型有的更高的精度和模型适应性。 相似文献
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研究了在输入输出观测数据均含有噪声时如何对基于Volterra级数描述的非线性系统进行解耦自适应辨识的问题. 按照Volterra级数模型的伪线性组合结构, 采用总体最小二乘辨识技术的原理, 导出了一种总体全解耦辨识的思想. 从而建立了一种具有全解耦结构的递阶式自适应辨识算法, 给出了该算法的结构图. 相比于部分解耦辨识算法, 该算法的优点在于它能够在全噪声数据环境下得到更高的收敛速度和精度. 仿真研究的结果证明了本文方法的有效性. 相似文献
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具有限定记忆的辅助变量参数辨识法与仿真研究 总被引:1,自引:0,他引:1
最小二乘参数辨识法可用于动态系统、静态系统、线性系统、非线性系统的参数估计。可用于离线估计,也可用于在线估计。最小二乘辨识法简单、实用,其递推算法收敛可靠,并且当模型噪声为白噪声时,可得到无偏、一致和有效的估计,从而得到广泛的应用。但当模型噪声是有色噪声时,最小二乘参数估计不是无偏、一致估计,并且随着数据的增长,最小二乘递推辨识算法将出现数据饱和现象,以致递推算法慢慢失去修正的能力。辅助变量递推算法解决了噪声的模型结构不确定且模型噪声是有色噪声时,最小二乘参数估计的元偏性和一致性问题,但依然存在数据饱和问题。为此在辅助变量递推算法的基础上引入限定记忆方式,获得了具有限定记忆的辅助变量参数估计递推算法,解决了辅助变量递推算法的数据饱和问题。仿真结果表明了该算法的有效性。 相似文献
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本文提出了一种用于设计径向基函数(RBF)网络的递阶免疫算法,并将采用这种递阶免疫算法设计的RBF网络用于DS-CDMA系统的多用户检测.该方法利用递阶免疫算法确定RBF网络隐层(非线性层)的结构和参数,采用最小二乘算法计算RBF网络的输出层权值.递阶免疫算法针对RBF网络的特点引入免疫算子,能够有效提高群体的适应度,加快算法的收敛速度.仿真结果表明,基于这种RBF网络的多用户检测器具有较强的抑制多址干扰和克服远近效应的能力. 相似文献
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多变量系统状态空间模型的递阶辨识 总被引:12,自引:1,他引:11
研究多变量系统状态空间模型的递阶辨识问题,推广了作者提出的标量系统状态和参数联合辨识算法.当状态可量测时,利用最小二乘原理直接辨识状态空间模型的参数矩阵;当状态不可测时,利用递阶辨识原理提出了状态空间模型递阶辨识方法,使用系统输入输出数据来估计系统的未知状态和参数.状态空间模型递阶辨识方法分为两步:首先假设系统状态是已知的(即参数估计算法中的未知系统状态用其估计代替),基于状态估计和系统输入输出数据递归计算系统参数估计;然后基于系统输入输出数据和获得的参数估计,递归计算系统的状态估计. 相似文献
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针对有理模型提出两类辨识方法.首先提出基于递阶辨识思想的混合辨识方法,将模型分解为分子和分母两个子模型,分别用最小二乘法辨识分子参数,用粒子群算法和智能多步长梯度迭代算法辨识分母参数.由于降低了模型维数,且信息向量与噪声不相关,相对于传统的偏差补偿最小二乘算法,混合迭代法可以提高辨识精度并降低计算量.然后,为消除模型结构已知的假设,且充分利用最新数据更新系统参数,提出柔性递推最小二乘辨识方法,将有理模型转化为时变参数系统,进而辨识出时变系统的参数.仿真例子验证了所提出方法的有效性. 相似文献
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辨识Box-Jenkins模型参数的递推广义增广最小二乘法 总被引:6,自引:0,他引:6
本文提出一种递推广义增广最小二乘辨识算法(RGELS)。该算法推广了递推增广最小二乘法(RELS),可用于一般模型(BOX-Jenkins模型)的参数辨识。数字仿真例子表明了算法的有效性。 相似文献
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This paper considers the identification problem for Hammerstein output error moving average (OEMA) systems. An auxiliary model-based recursive extended least-squares (RELS) algorithm and an auxiliary model-based multi-innovation extended least-squares (MI-ELS) algorithm are presented using the multi-innovation identification theory. The basic idea is to express the system output as a linear combination of the parameters by using the key-term separation principle and auxiliary model method. The proposed algorithms can give highly accurate parameter estimates. The simulation results show the effectiveness of the proposed algorithms. 相似文献
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The two-level hierarchical control scheme is adopted to solve a dual-chain robotic system formed by two redundant manipulators grasping a common object with hard point contacts. The upper-level coordinator gathers all the necessary information to resolve the force distribution problem so as to generate all the desired contact forces With all the desired contact forces being specified, the dynamics of each chain are decoupled. Therefore, the lower-level local control problem can be treated as a general open-chain redundant manipulator problem. Furthermore, the Compact-Dual LP method is applied to resolve the upper-level coordination problem; while the Compact QP method associated with the computed torque control method is adopted to solve the redundant manipulator problem. To obtain proper simulation results, the simulated actual contact forces are formulated and the corresponding simulation problem of the closed-chain robotic system is also completely solved in the article. Simulation results show that the two-level hierarchical control scheme is an effective and efficient algorithm for resolving the large-scale control problem of multiple-chain robotic systems. © 1995 John Wiley & Sons, Inc. 相似文献
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线性多变量系统的联合辨识算法 总被引:3,自引:1,他引:2
本文提出了同时估计线性多变量系统所有参数的联合辨识算法(CIA),并用随机过程理论分析了算法的收敛性。与子系统辨识算法(SSIA)相比,CIA的计算量要小得多。各输出间存在相互作用噪声时的辨识问题通过使用递推广义增广最小二乘法(RGELA)得到解决。数字仿真结果表明了CIA的有效性。 相似文献
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基于SMP集群的三维网格多粒度混合并行编程模型 总被引:2,自引:0,他引:2
为提高大规模三维网格并行算法的执行效率,针对SMP集群分布/共享两级内存层次结构的特点,介绍适用于SMP集群混合编程的不同实现方法.对三维网格模型最短路径问题的并行求解提出了多粒度混合并行编程模型,给出了实现该问题的MPI+OpenMP混合并行算法,并在SMP集群上同粗粒度MPI(Message Passing Interface)并行算法做了性能比较.结果表明,采用该多粒度混合并行编程模型具有更好的加速比和运行效率. 相似文献
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Schemes for system identification based on closed-loop experiments have attracted considerable interest lately. However, most of the existing approaches have been developed for discrete-time models. In this paper, the problem of continuoustime model identification is considered. A bias correction method without noise modelling associated with the Poisson moment functionals approach is presented for indirect identification of closed-loop systems. To illustrate the performances of the proposed method, the bias-eliminated least-squares algorithm is applied to the parameter estimation of a simulated system via Monte Carlo simulations. 相似文献
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Owing to the elegant properties of generalized block pulse operational matrices, a SID (system identification) matrix can be derived to identify transfer function coefficients of a linear time-invariant system from the unit step response data. The identification algorithm performs in a least-squares sense and can be recursive according to previous work. This approach not only yields satisfactory results but also provides a more precise and efficient method for the system identification problem. 相似文献
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The THTMTP (two-level hierarchical time minimization transportation problem) is an important problem arising in industries. In literature, there are only two approaches with shortcomings to solve the problem. In this paper, the THTMTP is formulated as a mathematical model applicable to the case in which the total available supply at the sources is no less than the total demand at the destinations. A feasible flow-based iterative algorithm named THTMTP-A is proposed to solve the THTMTP by constructing network with lower and upper arc capacities. It is proved that the THTMTP-A algorithm can find the optimal solution to the THTMTP in a polynomial time. The proposed THTMTP-A algorithm has good performance in terms of computer implementation, computational time and required memory for computation, and hence overcomes successfully the shortcomings of the two existing approaches. Computational experiments validate that the THTMTP-A algorithm is an efficient and robust method to solve the THTMTP, and can serve as efficient tool to solve other related optimization problems. 相似文献