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71.
Extending a class of continuous estimation of distribution algorithms to dynamic problems 总被引:1,自引:0,他引:1
In this paper, a class of continuous Estimation of Distribution Algorithms (EDAs) based on Gaussian models is analyzed to
investigate their potential for solving dynamic optimization problems where the global optima may change dramatically during
time. Experimental results on a number of dynamic problems show that the proposed strategy for dynamic optimization can significantly
improve the performance of the original EDAs and the optimal solutions can be consistently located. 相似文献
72.
Thomas W. Reiland 《Numerical Functional Analysis & Optimization》2013,34(3-4):301-323
We define order Lipschitz mappings from a Banach space to an order complete vector lattice and present a nonsmooth analysis for such functions. In particular, we establish properties of a generalized directional derivative and gradient and derive results concerning a calculus of generalized gradients (i.e., calculation of the generalized gradient of f when f = f1 + f2, f = f · 2, etc.). We show the relevance of the above analysis to nondifferentiaile programming by deriving optimality conditions for problems of the form min f(x) subject to x [euro] S. For S arbitrary we state the results in terms of cones of displacement of the feasible region at the optimal point; when S ={x ? A|g(x) ? B}, we obtain Kuhn-Tucker type results. 相似文献
73.
74.
75.
Ciro Cafforio 《Signal processing》1982,4(1):45-52
In this paper a physical interpretation is given of a method for the estimation of movements in television images. The method, already presented by the author in other papers, is based on a linear regression of the image derivatives, both spatial and temporal. It is shown that a centered finite differences approximation of the image differentials is mandatory to obtain good performances. Experimental results are issued to support theoretical conclusions. 相似文献
76.
谐波数检测的最大特征值变化率准则 总被引:1,自引:0,他引:1
本文提出了谐波数检测的最大特征值变化率准则(MEVRC),与AIC和MDL不同之处是MEV-RC不利用偏置项,它基于协方差矩阵的最小特征值的变化率来估计信号数目。计算机模拟结果表明,MEVRC的性能在常规信噪比条件下优于AIC,而在小信噪比条件下比MDL略好。 相似文献
77.
Aiming at the higher bit-rate occupation of motion vector encoding and more time load of full-searching strategies,a multi-resolution motion estimation and compensation algorithm based on adjacent prediction of frame difference was proposed.Differential motion detection was employed to image sequences and proper threshold was adopted to identify the connected region.Then the motion region was extracted to carry out motion estimation and motion compensation on it.The experiment results show that the encoding efficiency of motion vector is promoted,the complexity of motion es timation is reduced and the quality of the reconstruction image at the same bit-rate as Multi-Reso lution Motion Estimation (MRME) is improved. 相似文献
78.
非圆信号多级维纳滤波MUSIC测向算法 总被引:1,自引:0,他引:1
为降低非圆信号的MUSIC(记为NC-MUSIC)测向算法的计算量,提出了基于多级维纳滤波的NC-MUSIC算法.首先,该算法将非圆信号特性用于多级维纳滤波算法,构造出扩展阵列输出矩阵,利用多级维纳滤波的递推特性求出信号子空间,而不需要估计样本协方差矩阵和对其特征值分解;其次,为了进一步降低算法的计算量,推导出信号子空间的谱峰一维搜索公式进行非圆信号谱峰搜索的计算,快速估算出目标的方位值.仿真结果和计算复杂度分析表明,新算法不但在均方根误差性能上与其他快速算法相似,均接近于NC-MUSIC算法,具有良好的估计性能,而且降低了NC-MUSIC算法的计算最,使其计算复杂度小于非圆信号扩展传播算子快速测向算法的计算复杂度.证实了新算法快速有效的估计性能. 相似文献
79.
Tzu-Sheng Shane Hsu Timothy Fitzgerald Vincent Phuc Nguyen Trisha Patel Balakumar Balachandran 《Acta Mechanica Sinica》2017,33(2):327-340
Studies of fluid-structure interactions associated with flexible structures such as flapping wings require the capture and quantification of large motions of bodies that may be opaque. As a case study, motion capture of a free flying Manduca sexta, also known as hawkmoth, is con-sidered by using three synchronized high-speed cameras. A solid finite element (FE) representation is used as a reference body and successive snapshots in time of the displacement fields are reconstructed via an optimization procedure. One of the original aspects of this work is the formulation of an objective function and the use of shadow matching and strain-energy regularization. With this objective function, the authors penalize the projection differences between silhou-ettes of the captured images and the FE representation of the deformed body. The process and procedures undertaken to go from high-speed videography to motion estimation are dis-cussed, and snapshots of representative results are presented. Finally, the captured free-flight motion is also characterized and quantified. 相似文献
80.
We consider a fully discrete scheme for a quasistatic frictional contact problem between a viscoelastic body and an obstacle. The contact is bilateral, the friction is modeled with Tresca's law and the behavior of the material is described with a viscoelastic constitutive law with long memory. We state an existence and uniqueness result for the discrete solution, followed by error estimate results. Then, we present numerical simulations in the study of a two-dimensional test example. To cite this article: Á. Rodríguez-Arós et al., C. R. Mecanique 334 (2006). 相似文献