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101.
Daniel B. Szyld 《Numerical Linear Algebra with Applications》1994,1(2):151-154
Equivalence is shown between different conditions for convergence of iterative methods for consistent singular systems of linear equations on Banach spaces. These systems appear in many applications, such as Markov chains and Markov processes. The conditions considered relate the range and null spaces of different operators. 相似文献
102.
Nadaniela Egidi Romina Gobbi Pierluigi Maponi 《Journal of Computational and Applied Mathematics》2007,210(1-2):175-182
We consider an electromagnetic scattering problem for inhomogeneous media. In particular, we focus on the numerical computation of the electromagnetic scattered wave generated by the interaction of an electromagnetic plane wave and an inhomogeneity in the corresponding propagation medium. This problem is studied in the VV polarization case, where some special symmetry requirements for the incident wave and for the inhomogeneity are assumed. This problem is reformulated as a Fredholm integral equation of second kind, which is discretized by a linear system having a special form. This allows to compute efficiently an approximate solution of the scattering problem by using iterative techniques for linear systems. Some numerical examples are reported. 相似文献
103.
针对目前日益突出的电能质量问题,开发了通用电气变量检测与分析装置,介绍了其硬件及软件构成,并为减小测量误差进行了相应算法的分析与比较,在此基础上进行了仿真测试,取得了良好的成果。 相似文献
104.
一类广义KdV—Burgers型方程的拟谱方法 总被引:1,自引:0,他引:1
本文研究一类带三阶粘性项的广义Kdv-Burgers型方程的初值问题。运用拟谱方法,研究了拟谱格式的收敛性、稳定性.给出了数值例子. 相似文献
105.
This paper concerns the convex optimal control problem governed by multiscale elliptic equations with arbitrarily rough $L^\infty$ coefficients, which has not only complex coupling between nonseparable scales and nonlinearity, but also important applications in composite materials and geophysics. We use one of the recently developed numerical homogenization techniques, the so-called Rough Polyharmonic Splines (RPS) and its generalization (GRPS) for the efficient resolution of the elliptic operator on the coarse scale. Those methods have optimal convergence rate which do not rely on the regularity of the coefficients nor the concepts of scale-separation or periodicity. As the iterative solution of the nonlinearly coupled OCP-OPT formulation for the optimal control problem requires solving the corresponding (state and co-state) multiscale elliptic equations many times with different right hand sides, numerical homogenization approach only requires one-time pre-computation on the fine scale and the following iterations can be done with computational cost proportional to coarse degrees of freedom. Numerical experiments are presented to validate the theoretical analysis. 相似文献
106.
Quantum Bayesian computation is an emerging field that levers the computational gains available from quantum computers. They promise to provide an exponential speed-up in Bayesian computation. Our article adds to the literature in three ways. First, we describe how quantum von Neumann measurement provides quantum versions of popular machine learning algorithms such as Markov chain Monte Carlo and deep learning that are fundamental to Bayesian learning. Second, we describe quantum data encoding methods needed to implement quantum machine learning including the counterparts to traditional feature extraction and kernel embeddings methods. Third, we show how quantum algorithms naturally calculate Bayesian quantities of interest such as posterior distributions and marginal likelihoods. Our goal then is to show how quantum algorithms solve statistical machine learning problems. On the theoretical side, we provide quantum versions of high dimensional regression, Gaussian processes and stochastic gradient descent. On the empirical side, we apply a quantum FFT algorithm to Chicago house price data. Finally, we conclude with directions for future research. 相似文献
107.
For many motion control applications spatial constraints are often more important than temporal constraints. In recent work,
we have developed a spatial control strategy called the ε-controller for mobile robot applications. The control strategy is
based solely on static path geometry with position (in space) feedback. Motivated by this idea, in this paper, we consider
the notion of spatial-based iterative learning control (ILC). Specifically, we consider repetitive operation problems where
corrections are made to the control signal from trial to trial. Unlike traditional ILC, however, which updates control signals
based on the time elapsed along a trajectory, we instead make updates based on path errors and progress along the path. The
idea is demonstrated via simulation for a system with bang–bang velocity control. Experimental results using a high-precision,
two-axis gimbal mechanism are presented to show the effectiveness of the strategy. 相似文献
108.
A finite difference method is developed for the numerical modelling of the 2-D and 3-D unsteady potential flow generated by
transient disturbances on the free surface, on which the nonlinear boundary conditions are fully satisfied. The unknown function
is computed with an iteration scheme processing in a transformed time-invariant space. After the velocity is calculated, the
location of the free surface is renewed and so is the value of velocity on it. The boundary-value problem of the governing
equation is then solved at the next time step. The present method incorporates the FFT. Consequently, a tri-diagonal equation
system is obtained which could be readily solved. The feasibility of this method has been demonstrated by 2-D and 3-D examples
corresponding to different initial disturbances.
This work is supported by the science foundation of Academia Sinica.
The paper had been accepted by the XVIth International Congress of IUTAM, Lyngby, Denmark, August, 1984. 相似文献
109.
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