Taisuke Ozaki

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This paper gives stability analysis of the nonlinear predictive control strategy based on the off-line identified RBF-ARX model which is a pseudo-linear time-varying ARX model with system working-point dependent Gaussian RBF neural network style coefficients. The predictive controller doesn't require on-line parameter estimation; it may be applied to a(More)
In this paper an approximate innovation method is introduced for the estimation of diffusion processes given a set of discrete and noisy observations of some of their components. The method is based on a recent extension of Local Linearization filters to the general case of continuous-discrete state space models with multiplicative noise. This filtering(More)
We address the issue of testing for nonlinearity in time series from continuous dynamics and propose a quantitative measure for nonlinearity which is based on discrete parametric modelling. The well-known problems of modelling continuous dynamical systems by discrete models are addressed by a subsampling approach. This measure should preferably be combined(More)
With tens of petaflops supercomputers already in operation and exaflops machines expected to appear within the next 10 years, efficient parallel computational methods are required to take advantage of such extreme-scale machines. In this paper, we present a three-dimensional domain decomposition scheme for enabling large-scale electronic calculations based(More)
The fast Fourier transform (FFT) is undoubtedly an essential primitive that has been applied in various fields of science and engineering. In this paper, we present a decomposition method for parallelization of multi-dimensional FFTs with smallest communication amount for all ranges of the number of processes compared to previously proposed methods. This is(More)
The widespread popularity of density functional theory has given rise to an extensive range of dedicated codes for predicting molecular and crystalline properties. However, each code implements the formalism in a different way, raising questions about the reproducibility of such predictions. We report the results of a community-wide effort that compared 15(More)
A numerical method to calculate the four-center electron-repulsion integrals for strictly localized pseudoatomic orbital basis sets has been developed. Compared to the conventional Gaussian expansion method, this method has an advantage in the ease of combination with O(N) density functional calculations. Additional mathematical derivations are also(More)
We present a DFT study for the adsorption of single Pt atom and Pt clusters on graphene surface and carbon nanotube. Adsorption of a Pt atom shows a heavy dependence of binding energy on the graphene curvature. The adsorbed Pt atoms tend to form clusters, than to disperse on the graphene surface. The Pt–Pt bond length and the charge transfer from Pt(More)