著者
Yuji ITO Kenji FUJIMOTO
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences (ISSN:09168508)
巻号頁・発行日
vol.E105-A, no.1, pp.1-10, 2022-01-01

Recently, control theory using machine learning, which is useful for the control of unknown systems, has attracted significant attention. This study focuses on such a topic with optimal control problems for unknown nonlinear systems. Because optimal controllers are designed based on mathematical models of the systems, it is challenging to obtain models with insufficient knowledge of the systems. Kernel functions are promising for developing data-driven models with limited knowledge. However, the complex forms of such kernel-based models make it difficult to design the optimal controllers. The design corresponds to solving Hamilton-Jacobi (HJ) equations because their solutions provide optimal controllers. Therefore, the aim of this study is to derive certain kernel-based models for which the HJ equations are solved in an exact sense, which is an extended version of the authors' former work. The HJ equations are decomposed into tractable algebraic matrix equations and nonlinear functions. Solving the matrix equations enables us to obtain the optimal controllers of the model. A numerical simulation demonstrates that kernel-based models and controllers are successfully developed.
著者
Shigeaki Moriura Satoko Ono Kumiko Sugiyama Satoshi Ito Yuji Ito
出版者
Japan Society of Ningen Dock
雑誌
Ningen Dock International (ISSN:21878072)
巻号頁・発行日
vol.3, no.1, pp.20-22, 2016 (Released:2018-12-10)
参考文献数
5

Background: The management of asymptomatic pneumonia-like opacity detected by CT has not been clarified.Methods: We reviewed 12 cases of asymptomatic pneumonia-like opacity from 2,762 chest CTs performed at our check-up center between 2012 and 2014. Cases under treatment for respiratory disorders and those suspicious of specific infections were excluded.Results: In all 12 cases, CT findings of pneumonia-like opacity disappeared without chemotherapy.Conclusion: Patients with asymptomatic pneumonia-like opacity can be managed by observation if chronic respiratory disorders and specific infections have been ruled out.