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1. Dependence of the Solar Wind Plasma Density on Moderate Geomagnetic Activity Elucidated by Potential Learning

Author

Kitajima, Ryozo, Nowada, Motoharu, and Kamimura, Ryotaro

Subjects
Physics - Space Physics, Physics - Computational Physics, Physics - Data Analysis, Statistics and Probability, Physics - Plasma Physics
Abstract

The relationship between a moderate level of geomagnetic activity, represented by Kp (2- - 5+), and solar wind conditions was revealed using Potential Learning (PL). We also discussed dependence of particular solar wind plasma density on moderate geomagnetic conditions. It has poorly been understood from what stage of geomagnetic activity solar wind density begins to control Kp. Previously, PL succeeded to extract the most influential solar wind parameters at an extremely low (0 - 1+) and high (6- - 9) Kp under southward IMF conditions. The IMF three components, solar wind flow speed, and plasma density obtained from the 22 years' OMNI solar wind database were used as the inputs. PL extracted the solar wind velocity as the most significant, and further solar wind number density was the second most influential parameter for the moderate Kp under southward IMF conditions. This result was the same as the previous PL result in relation between extremely low and high Kp for southward IMF. Based on statistical investigations using solar wind speed and plasma density database used in PL under extremely low, high, and moderate Kp, geomagnetic conditions remain high while the plasma number density becomes large, even if the solar wind velocity is slow. This shows that not only solar wind velocity but also plasma density plays a crucial role in causing geomagnetic disturbances, following empirical relation between Kp and the solar wind plasma parameter. The results obtained from PL and incidental statistical investigations using the PL database suggest that the solar wind density begins to affect Kp from moderate geomagnetic activity even under southward IMF conditions. They also would greatly help not only understand general relationship between solar wind conditions and geomagnetic activity but also forecast geomagnetic activity under various IMF conditions., Comment: Manuscript: 41 pages Graphical Abstract: 1 page Table: 2 pages Figures: 7 pages

Published
2024

2. Investigation of the Relationship between Geomagnetic Activity and Solar Wind Parameters Based on A Novel Neural Network (Potential Learning)

Author

Kitajima, Ryozo, Nowada, Motoharu, and Kamimura, Ryotaro

Subjects
Physics - Space Physics
Abstract

Predicting geomagnetic conditions based on in-situ solar wind observations allows us to evade disasters caused by large electromagnetic disturbances originating from the Sun to save lives and protect economic activity. In this study, we aimed to examine the relationship between the Kp index, representing global magnetospheric activity level, and solar wind conditions using an interpretable neural network known as potential learning (PL). Data analyses based on neural networks are difficult to interpret; however, PL learns by focusing on the "potentiality of input neurons" and can identify which inputs are significantly utilized by the network. Using the full advantage of PL, we extracted the influential solar wind parameters that disturb the magnetosphere under southward Interplanetary magnetic field (IMF) conditions. The input parameters of PL were the three components of the IMF (Bx, By, -Bz(Bs)), solar wind flow speed (Vx), and proton number density (Np) in geocentric solar ecliptic (GSE) coordinates obtained from the OMNI solar wind database between 1998 and 2019. Furthermore, we classified these input parameters into two groups (targets), depending on the Kp level: Kp = 6- to 9 (positive target) and Kp = 0 to 1+ (negative target). Negative target samples were randomly selected to ensure that numbers of positive and negative targets were equal. The PL results revealed that solar wind flow speed is an influential parameter for increasing Kp under southward IMF conditions, which was in good agreement with previous reports on the statistical relationship between the Kp index and solar wind velocity, and the Kp formulation based on the IMF and solar wind plasma parameters. Based on this new neural network, we aim to construct a more correct and parameter-dependent space weather forecasting model., Comment: This PDF is including the manuscript with 18 pages, 4 figures, 3 tables, and 1 graphical abstract. This paper has submitted to Earth, Planets and Space (EPS) and is under review. Also this paper has two corresponding authors: Ryozo Kitajima, and Motoharu Nowada. These two authors equally contribute to completing this paper

Published
2022
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4. Comprehensive Potentiality Maximization to Improve and Interpret Multi-Layered Neural Networks

Author

Kamimura, Ryotaro, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, Abraham, Ajith, editor, Hanne, Thomas, editor, Gandhi, Niketa, editor, Manghirmalani Mishra, Pooja, editor, Bajaj, Anu, editor, and Siarry, Patrick, editor

Published
2023
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5. Repeated Potentiality Augmentation for Multi-layered Neural Networks

Author

Kamimura, Ryotaro, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, and Arai, Kohei, editor

Published
2023
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6. Min-Max Cost and Information Control in Multi-layered Neural Networks

Author

Kamimura, Ryotaro, Kitajima, Ryozo, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, and Arai, Kohei, editor

Published
2023
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7. Serially Disentangled Learning for Multi-Layered Neural Networks

Author

Kamimura, Ryotaro, Kitajima, Ryozo, Goos, Gerhard, Founding Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Fujita, Hamido, editor, Fournier-Viger, Philippe, editor, Ali, Moonis, editor, and Wang, Yinglin, editor

Published
2022
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8. Selective Information Control and Layer-Wise Partial Collective Compression for Multi-Layered Neural Networks

Author

Kamimura, Ryotaro, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, Abraham, Ajith, editor, Gandhi, Niketa, editor, Hanne, Thomas, editor, Hong, Tzung-Pei, editor, Nogueira Rios, Tatiane, editor, and Ding, Weiping, editor

Published
2022
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13. Controlling Potential Information to Unify Internal Structure for Improved Interpretation and Generalization in Multi-layered Neural Networks

Author

Kamimura, Ryotaro, Kacprzyk, Janusz, Series Editor, Pal, Nikhil R., Advisory Editor, Bello Perez, Rafael, Advisory Editor, Corchado, Emilio S., Advisory Editor, Hagras, Hani, Advisory Editor, Kóczy, László T., Advisory Editor, Kreinovich, Vladik, Advisory Editor, Lin, Chin-Teng, Advisory Editor, Lu, Jie, Advisory Editor, Melin, Patricia, Advisory Editor, Nedjah, Nadia, Advisory Editor, Nguyen, Ngoc Thanh, Advisory Editor, Wang, Jun, Advisory Editor, and Arai, Kohei, editor

Published
2021
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14. Cost-Conscious Internal Information Maximization for Disentangling and Interpreting Multi-layered Neural Networks

Author

Kamimura, Ryotaro, Kacprzyk, Janusz, Series Editor, Pal, Nikhil R., Advisory Editor, Bello Perez, Rafael, Advisory Editor, Corchado, Emilio S., Advisory Editor, Hagras, Hani, Advisory Editor, Kóczy, László T., Advisory Editor, Kreinovich, Vladik, Advisory Editor, Lin, Chin-Teng, Advisory Editor, Lu, Jie, Advisory Editor, Melin, Patricia, Advisory Editor, Nedjah, Nadia, Advisory Editor, Nguyen, Ngoc Thanh, Advisory Editor, Wang, Jun, Advisory Editor, Abraham, Ajith, editor, Hanne, Thomas, editor, Castillo, Oscar, editor, Gandhi, Niketa, editor, Nogueira Rios, Tatiane, editor, and Hong, Tzung-Pei, editor

Published
2021
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15. Bidirectional Estimation of Partially Black-Boxed Layers of SOM-Based Convolutional Neural Networks

Author

Kamimura, Ryotaro, Kacprzyk, Janusz, Series Editor, Pal, Nikhil R., Advisory Editor, Bello Perez, Rafael, Advisory Editor, Corchado, Emilio S., Advisory Editor, Hagras, Hani, Advisory Editor, Kóczy, László T., Advisory Editor, Kreinovich, Vladik, Advisory Editor, Lin, Chin-Teng, Advisory Editor, Lu, Jie, Advisory Editor, Melin, Patricia, Advisory Editor, Nedjah, Nadia, Advisory Editor, Nguyen, Ngoc Thanh, Advisory Editor, Wang, Jun, Advisory Editor, Arai, Kohei, editor, Kapoor, Supriya, editor, and Bhatia, Rahul, editor

Published
2021
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17. Compressing and Interpreting SOM-Based Convolutional Neural Networks

Author

Kamimura, Ryotaro, Goos, Gerhard, Founding Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Woeginger, Gerhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Fujita, Hamido, editor, Fournier-Viger, Philippe, editor, Ali, Moonis, editor, and Sasaki, Jun, editor

Published
2020
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21. Excessive, Selective and Collective Information Processing to Improve and Interpret Multi-layered Neural Networks

Author

Kamimura, Ryotaro, Takeuchi, Haruhiko, Kacprzyk, Janusz, Series Editor, Pal, Nikhil R., Advisory Editor, Bello Perez, Rafael, Advisory Editor, Corchado, Emilio S., Advisory Editor, Hagras, Hani, Advisory Editor, Kóczy, László T., Advisory Editor, Kreinovich, Vladik, Advisory Editor, Lin, Chin-Teng, Advisory Editor, Lu, Jie, Advisory Editor, Melin, Patricia, Advisory Editor, Nedjah, Nadia, Advisory Editor, Nguyen, Ngoc Thanh, Advisory Editor, Wang, Jun, Advisory Editor, Arai, Kohei, editor, Kapoor, Supriya, editor, and Bhatia, Rahul, editor

Published
2019
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25. Information-Theoretic Self-compression of Multi-layered Neural Networks

Author

Kamimura, Ryotaro, Hutchison, David, Editorial Board Member, Kanade, Takeo, Editorial Board Member, Kittler, Josef, Editorial Board Member, Kleinberg, Jon M., Editorial Board Member, Mattern, Friedemann, Editorial Board Member, Mitchell, John C., Editorial Board Member, Naor, Moni, Editorial Board Member, Pandu Rangan, C., Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Terzopoulos, Demetri, Editorial Board Member, Tygar, Doug, Editorial Board Member, Weikum, Gerhard, Series Editor, Goos, Gerhard, Founding Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Woeginger, Gerhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Fagan, David, editor, Martín-Vide, Carlos, editor, O'Neill, Michael, editor, and Vega-Rodríguez, Miguel A., editor

Published
2018
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33. Simple and Stable Internal Representation by Potential Mutual Information Maximization

Author

Kamimura, Ryotaro, Diniz Junqueira Barbosa, Simone, Series editor, Chen, Phoebe, Series editor, Du, Xiaoyong, Series editor, Filipe, Joaquim, Series editor, Kara, Orhun, Series editor, Kotenko, Igor, Series editor, Liu, Ting, Series editor, Sivalingam, Krishna M., Series editor, Washio, Takashi, Series editor, Jayne, Chrisina, editor, and Iliadis, Lazaros, editor

Published
2016
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34. Collective Interpretation and Potential Joint Information Maximization

Author

Kamimura, Ryotaro, Rannenberg, Kai, Editor-in-chief, Sakarovitch, Jacques, Series editor, Goedicke, Michael, Series editor, Tatnall, Arthur, Series editor, Neuhold, Erich J., Series editor, Pras, Aiko, Series editor, Tröltzsch, Fredi, Series editor, Pries-Heje, Jan, Series editor, Whitehouse, Diane, Series editor, Reis, Ricardo, Series editor, Furnell, Steven, Series editor, Furbach, Ulrich, Series editor, Gulliksen, Jan, Series editor, Rauterberg, Matthias, Series editor, Shi, Zhongzhi, editor, Vadera, Sunil, editor, and Li, Gang, editor

Published
2016
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35. Solving the Vanishing Information Problem with Repeated Potential Mutual Information Maximization

Author

Kamimura, Ryotaro, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Weikum, Gerhard, Series editor, Hirose, Akira, editor, Ozawa, Seiichi, editor, Doya, Kenji, editor, Ikeda, Kazushi, editor, Lee, Minho, editor, and Liu, Derong, editor

Published
2016
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40. Impartial competitive learning in multi-layered neural networks.

Author

Kamimura, Ryotaro

Abstract

The present paper aims to propose a new learning and interpretation method called "impartial competitive learning", meaning that all participants in a competition should be winners. Due to its importance, the impartiality is forced to be realised even by increasing the corresponding cost in terms of the strength of weights. For the first approximation, three types of impartial competition can be developed: componential, computational, and collective competition. In the componential competition, every weight should have an equal chance on average to win the competition. In the computational competition, all computational procedures should have an equal chance to be applied sequentially in learning. In collective computing for interpretation, all network configurations, obtained by learning, have an equal chance to participate in a process of interpretation, representing one of the most idealised forms of impartiality. The method was applied to a well-known second-language-learning data set. The intuitive conclusion, stressed in the specific science, could not be extracted by the conventional natural language processing methods, because they can deal only with word frequency. The present method tried to extract a main feature beyond the word frequency by competing connection weights and computational procedures impartially, followed by collective and impartial competition for interpretation. [ABSTRACT FROM AUTHOR]

Published
2023
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41. Principal Hidden Unit Analysis: Generation and Interpretation of Principal Networks by Zminimum Entropy Method

Author

Kamimura, Ryotaro

Abstract

In the present paper, a principal hiddenunit analysis with entropy minimization isproposed to obtain a simple or fundamentalstructure from original complex structures.The principal hidden unit analysis is com-posed of four steps. First, entropy, definedwith respect to the hidden unit activity, isminimized. Second, several principal hiddenunits are selected, according to il-index, rep-resenting the strength of the response of hid-den units to input patterns. Third, the per-formance of the obtained principal network isexamined with respect to the error or generalization. Finally, the internal representa-tion of the obtained principal network mustappropriately be interpreted. Applied to arule-plus-exception, a symmetry problem andan autoencoder, it was confirmed in all casesthat by using entropy method, a small num-ber of principal hidden units were selected.With these principal hidden units, principalnetworks were constructed, producing targetsalmost perfectly. The internal representationcould easily be interpreted especially for simple problems

Published
1993

43. Separation and Unification of Individuality and Collectivity and Its Application to Explicit Class Structure in Self-Organizing Maps

Author

Kamimura, Ryotaro, Hutchison, David, editor, Kanade, Takeo, editor, Kittler, Josef, editor, Kleinberg, Jon M., editor, Mattern, Friedemann, editor, Mitchell, John C., editor, Naor, Moni, editor, Nierstrasz, Oscar, editor, Pandu Rangan, C., editor, Steffen, Bernhard, editor, Sudan, Madhu, editor, Terzopoulos, Demetri, editor, Tygar, Doug, editor, Vardi, Moshe Y., editor, Weikum, Gerhard, editor, Villa, Alessandro E. P., editor, Duch, Włodzisław, editor, Érdi, Péter, editor, Masulli, Francesco, editor, and Palm, Günther, editor

Published
2012
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44. Explicit Class Structure by Weighted Cooperative Learning

Author

Kamimura, Ryotaro, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Sudan, Madhu, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Vardi, Moshe Y., Series editor, Weikum, Gerhard, Series editor, Honkela, Timo, editor, Duch, Włodzisław, editor, Girolami, Mark, editor, and Kaski, Samuel, editor

Published
2011
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45. Information-Theoretic Competitive and Cooperative Learning for Self-Organizing Maps

Author

Kamimura, Ryotaro, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Sudan, Madhu, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Vardi, Moshe Y., Series editor, Weikum, Gerhard, Series editor, Wong, Kok Wai, editor, Mendis, B. Sumudu U., editor, and Bouzerdoum, Abdesselam, editor

Published
2010
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46. Pseudo-network Growing for Gradual Interpretation of Input Patterns

Author

Kamimura, Ryotaro, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Sudan, Madhu, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Vardi, Moshe Y., Series editor, Weikum, Gerhard, Series editor, Wong, Kok Wai, editor, Mendis, B. Sumudu U., editor, and Bouzerdoum, Abdesselam, editor

Published
2010
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47. Generation of Comprehensible Representations by Supposed Maximum Information

Author

Kamimura, Ryotaro, Hutchison, David, Kanade, Takeo, Kittler, Josef, Kleinberg, Jon M., Mattern, Friedemann, Mitchell, John C., Naor, Moni, Nierstrasz, Oscar, Pandu Rangan, C., Steffen, Bernhard, Sudan, Madhu, Terzopoulos, Demetri, Tygar, Doug, Vardi, Moshe Y., Weikum, Gerhard, Diamantaras, Konstantinos, editor, Duch, Wlodek, editor, and Iliadis, Lazaros S., editor

Published
2010
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49. Collective Activations to Generate Self-Organizing Maps

Author

Kamimura, Ryotaro, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Sudan, Madhu, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Vardi, Moshe Y., Series editor, Weikum, Gerhard, Series editor, Köppen, Mario, editor, Kasabov, Nikola, editor, and Coghill, George, editor

Published
2009
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50. Enhanced Visualization by Combing SOM and Mixture Models

Author

Kamimura, Ryotaro, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Sudan, Madhu, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Vardi, Moshe Y., Series editor, Weikum, Gerhard, Series editor, Köppen, Mario, editor, Kasabov, Nikola, editor, and Coghill, George, editor

Published
2009
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