Akira Imakura

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This study was performed to test the validity and value of the Schizophrenia Quality of Life Scale as an assessment tool in a Japanese-language version (JSQLS). The subjects for the present study were 55 inpatients with a diagnosis of schizophrenia as defined by DSM-IV. The JSQLS was administered together with two other self-report measures, the Medical(More)
BACKGROUND In Western nations the effect of ECT has been re-evaluated since the 1970s, while reports on ECT are few in Japan. METHODS The sample included 3,067 patients admitted to Tokushima University Hospital between 1975 and 1997. Hospital charts were reviewed retrospectively for ECT. RESULTS ECT was carried out on 6.03% of all subjects; 11.97% of(More)
We investigate contour integral-based eigensolvers for computing all eigenvalues located in a certain region and their corresponding eigenvectors. In this paper, we focus on a Rayleigh–Ritz type method and analyze its error bounds. From the results of our analysis, we conclude that the Rayleigh–Ritz type contour integral-based eigensolver with sufficient(More)
We present a newly developed moving-mesh technique for the multi-dimensional Boltzmann-Hydro code for the simulation of core-collapse supernovae (CCSNe). What makes this technique different from others is the fact that it treats not only hydrodynamics but also neutrino transfer in the language of the 3+1 formalism of general relativity (GR), making use of(More)
Complex moment-based eigensolvers for solving interior eigenvalue problems have been studied because of their high parallel efficiency. Recently, we proposed the block Arnoldi-type complex moment-based eigensolver without a low-rank approximation. A low-rank approximation plays a very important role in reducing computational cost and stabilizing accuracy in(More)
For computing weights of deep neural networks (DNNs), the backpropagation (BP) method has been widely used as a de-facto standard algorithm. Since the BP method is based on a stochastic gradient descent method using derivatives of objective functions, the BP method has some difficulties finding appropriate parameters such as learning rate. As another(More)
A Workshop on Numerical Algebra, Algorithms, and Analysis in honor of Professor Ken Hayami’s 60th birthday was held at the National Institute of Informatics, Tokyo, Japan, on January 11–12, 2016. Over 30 participants including 13 invited speakers from China, Germany, Japan, Spain, and USA presented talks, shared ideas, and had lively discussions on a wide(More)
The backpropagation algorithm for calculating gradients has been widely used in computation of weights for deep neural networks (DNNs). This method requires derivatives of objective functions and has some difficulties finding appropriate parameters such as learning rate. In this paper, we propose a novel approach for computing weight matrices of(More)