著者

Hideaki Yamamoto Ayumi Hirano-Iwata Shigeo Sato

出版者

The Japan Society of Applied Physics

雑誌

JSAP Review (ISSN:24370061)

巻号頁・発行日

vol.2023, pp.230420, 2023 (Released:2023-07-06)

参考文献数

18

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The structure and function of complex neuronal networks in the brain can be partially reconstituted in vitro by integrating cell culture and microfluidic device technologies. In this report, we review our recent studies on developing microfluidic devices to reconstitute small neuronal networks bearing a modular structure, which is a canonical structure found in the nervous systems of animals. We also describe the process of recording functional activity from the reconstituted neuronal networks. These fundamental technologies offer novel tools for investigating structure–function relationships in living neuronal networks and exploring the physical basis of biological computing in the brain.

著者

Daisuke Oguchi Satoshi Moriya Hideaki Yamamoto Shigeo Sato

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

Nonlinear Theory and Its Applications, IEICE (ISSN:21854106)

巻号頁・発行日

vol.13, no.2, pp.427-433, 2022 (Released:2022-04-01)

参考文献数

10

被引用文献数

1

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Reinforcement learning is promising as a machine learning paradigm in edge computing. However, its high computational cost poses a challenge when implementing in devices with limited circuit resources and power consumption. In this study, we investigated the relationship between the bit-length of floating-point operations and the learning performance of the reinforcement learning algorithm. In the case of the FrozenLake maze problem, we found that the learning performance of 8-bit floating-point arithmetic decreased, while that of 16-bit floating-point arithmetic was comparable to that of 64-bit CPU arithmetic. Our results provide a practical guideline for designing a dedicated reinforcement learning hardware with minimum circuit resources and power consumption.

著者

Eiichiro Matsubara Shigeo Sato Muneyuki Imafuku Takahiro Nakamura Hisato Koshiba Akihisa Inoue Yoshio Waseda

出版者

The Japan Institute of Metals

雑誌

Materials Transactions, JIM (ISSN:09161821)

巻号頁・発行日

vol.41, no.11, pp.1379-1384, 2000 (Released:2007-06-01)

参考文献数

15

被引用文献数

13 14

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This paper has been retracted by the Editorial Committee with the first author’s agreement due to substantial overlap with the following paper previously received in another journal. Mater. Sci. Eng. A 312 (2001) 136-144 Structural study of Amorphous Fe70M10B20 (M=Zr, Nb and Cr) alloys by X-ray diffraction E. Matsubara, S. Sato, M. Imafuku, T. Nakamura, H. Koshiba, A. Inoue, Y. Waseda (Received on May 8, 2000) And thus, it shall not be regarded as an original paper. Although this paper was submitted to the Special Issue on Bulk Amorphous, Nano-Crystalline and Nano-Quasicrystalline Alloys by the first author without understanding the bylaws of Materials Transactions, JIM, it was not an appropriate deed. The first author acknowledges the substantial overlap and his apologies have been accepted accordingly. The notice has been issued to all the authors to pay more careful attention in submitting papers.

著者

Shigeru Suzuki Koji Hotta Eui Pyo Kwon Shun Fujieda Kozo Shinoda Masayoshi Kumagai Kentaro Kajiwara Masugu Sato Shigeo Sato

出版者

一般社団法人 日本鉄鋼協会

雑誌

ISIJ International (ISSN:09151559)

巻号頁・発行日

vol.55, no.10, pp.2158-2165, 2015-10-15 (Released:2015-10-28)

参考文献数

48

被引用文献数

7

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Electron backscatter diffraction was used to observe the microstructure of an austenitic high-manganese twinning-induced plasticity steel and investigate the crystal orientation of grains in this steel. The results showed that mechanical twins are formed in a grain with a high Schmid factor during the tensile test. The orientation data obtained were used to estimate the anisotropic elasticity of the grains in the steel. The microscopic stress and strain evolved in the microstructure of the steel unloaded after plastic deformation were estimated using finite element method simulation in which the elastic anisotropy of the steel was taken into account. The simulation indicated that the evolution of microscopic stress and strain in the microstructure is considerably influenced by the crystal orientation of the grains. Furthermore, white X-ray diffraction with microbeam synchrotron radiation was used to characterize the evolution of microscopic stress and strain in the grains of the steel. The stress analysis during white X-ray diffraction indicated the formation of residual microscopic stress after tensile deformation, which was found to be distributed heterogeneously in the steel. It was also shown that the direction of the maximum principal stresses at different points in the microstructure under loading were mostly oriented along the tensile direction. These results are fairly consistent with the results obtained by the simulation, although absolute values of the real principal stresses may be influenced by the heterogeneously evolved strain and the several assumptions used in the simulation.

著者

Masayoshi Kumagai Shigeo Sato Shigeru Suzuki Muneyuki Imafuku Hitoshi Tashiro Shin-ichi Ohya

出版者

一般社団法人 日本鉄鋼協会

雑誌

ISIJ International (ISSN:09151559)

巻号頁・発行日

vol.55, no.7, pp.1489-1495, 2015-07-15 (Released:2015-07-30)

参考文献数

19

被引用文献数

1 3

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Measurement of the residual stresses in cold-drawn pearlitic steel wire was conducted using an energy dispersive X-ray diffraction technique. The residual stresses of the ferrite and cementite phases were determined for different crystal orientations and large residual stresses were found to exist in the cold-drawn pearlitic steel wire. The residual stresses in the ferrite phase were compressive in the axial direction but nearly zero in the hoop and radial directions. In addition, the residual stresses of the reflection indices for the ferrite phase were similar to one another. For the cementite phase, while tensile residual stress existed in the axial direction, compressive residual stress existed in the hoop and radial directions. These stresses in the ferrite phase in the axial direction and cementite phase in all directions decreased along the radial positions. A residual stress state model was proposed on the basis of the aligned lamellar structure along the drawing direction; the model explains the effect of the lamellar direction on residual stress. Reanalysis of the wire sample using the proposed model provided residual strains and stresses in the lamellar direction that were different from the average values estimated using the simple stress analysis method.