Emi Minamitani, Takenobu Nakamura, Ippei Obayashi & Hideyuki Mizuno. Persistent homology elucidates hierarchical structures responsible for mechanical properties in covalent amorphous solids. Nature Communications 16, Article number: 8226 (2025). https://doi.org/10.1038/s41467-025-63424-z
Michiki Taniwaki, Ryunosuke Nagaoka, Ken Masuzawa, Shunsuke Sato, Alexandre Lira Foggiatto, Chiharu Mitsumata, Takahiro Yamazaki, Ippei Obayashi, Yasuaki Hiraoka, Yasuhiko Igarashi, Yuta Mizutori, Sepehri Amin Hossein, Tadakatsu Ohkubo, Hisashi Mogi and Masato Kotsugi. Automated identification of the origin of energy loss in nonoriented electrical steel by feature extended Ginzburg–Landau free energy framework. Scientific Reports. 15, Article number: 23758 (2025). https://doi.org/10.1038/s41598-025-00357-z
Misato Tone, Shunsuke Sato, Sotaro Kunii, Ippei Obayashi, Yasuaki Hiraoka, Yui Ogawa, Hirokazu Fukidome, Alexandre Lira Foggiatto, Chiharu Mitsumata, Ryunsuke Nagaoka, Arpita Varadwaj, Iwao Matsuda, and Masato Kotsugi. Linking structure and process in dendritic growth using persistent homology with energy analysis. Science and Technology of Advanced Materials: Methods. 5(1), (2025) https://doi.org/10.1080/27660400.2025.2475735
Naoto Kitamura, Hikari Matsubara, Koji Kimura, Ippei Obayashi, Yohei Onodera, Ken Nakashima, Hidetoshi Morita, Motoki Shiga, Yasuhiro Harada, Chiaki Ishibashi, Yasushi Idemoto and Koichi Hayashi. Relationship between network topology and negative electrode properties in Wadsley–Roth phase TiNb2O7. NPG Asia Materials, 16, Article number: 62 (2024). https://doi.org/10.1038/s41427-024-00581-5
R. Nagaoka, K. Masuzawa, M. Taniwaki, A. L. Foggiatto, T. Yamazaki, I. Obayashi, Y. Hiraoka, C. Mitsumata, M. Kotsugi. Quantification of the coercivity factor in soft magnetic materials at different frequencies using topological data analysis. IEEE Transactions on Magnetics, 60 (9), Art no. 4000305, 1–5, (2024). https://doi.org/10.1109/TMAG.2024.3408002
A. L. Foggiatto, R. Nagaoka, M. Taniwaki, T. Yamazaki, T. Ogasawara, I. Obayashi, Y. Hiraoka, C. Mitsumata, M. Kotsugi. Analysis of the excess loss in high-frequency magnetization process through machine learning and topological data analysis. vol. 60, no. 9, pp. 1-5, Sept. 2024, Art IEEE Transactions on Magnetics, 60 (9), Art no. 7001305, 1–5 (2024). https://doi.org/10.1109/TMAG.2024.3406717
Yuta Shuseki, Shinji Kohara, Tomoaki Kaneko, Keitaro Sodeyama, Yohei Onodera, Chihiro Koyama, Atsunobu Masuno, Shunta Sasaki, Shohei Hatano, Motoki Shiga, Ippei Obayashi, Yasuaki Hiraoka, Junpei T. Okada, Akitoshi Mizuno, Yuki Watanabe, Yui Nakata, Koji Ohara, Motohiko Murakami, Matthew G. Tucker, Marshall T. McDonnell, Hirohisa Oda, and Takehiko Ishikawa. Atomic and Electronic Structure in MgO–SiO2. J. Phys. Chem. A 128 (4), 716–726 (2024). https://doi.org/10.1021/acs.jpca.3c05561
Emi Minamitani, Ippei Obayashi, Koji Shimizu, and Satoshi Watanabe. Persistent homology-based descriptor for machine-learning potential of amorphous structures. The Journal of Chemical Physics 159, 084101 (2023). https://doi.org/10.1063/5.0159349
Ippei Obayashi, and Masao Kimura. Persistent homology analysis with nonnegative matrix factorization for 3D voxel data of iron ore sinters. JSIAM Letters 14, 151–154 (2022) https://doi.org/10.14495/jsiaml.14.151
Emi Minamitani, Takuma Shiga, Makoto Kashiwagi, and Ippei Obayashi. Topological descriptor of thermal conductivity in amorphous Si. J. Chem. Phys. 156, 244502 (2022) https://doi.org/10.1063/5.0093441
Emi Minamitani, Takuma Shiga, Makoto Kashiwagi, and Ippei Obayashi. Relationship between local coordinates and thermal conductivity in amorphous carbon. Journal of Vacuum Science & Technology A 40, 033408 (2022). https://doi.org/10.1116/6.0001744
Yohei Onodera, Shinji Kohara, Philip S. Salmon, Akihiko Hirata, Norimasa Nishiyama, Suguru Kitani, Anita Zeidler, Motoki Shiga, Atsunobu Masuno, Hiroyuki Inoue, Shuta Tahara, Annalisa Polidori, Henry E. Fischer, Tatsuya Mori, Seiji Kojima, Hitoshi Kawaji, Alexander I. Kolesnikov, Matthew B. Stone, Matthew G. Tucker, Marshall T. McDonnell, Alex C. Hannon, Yasuaki Hiraoka, Ippei Obayashi, Takenobu Nakamura, Jaakko Akola, Yasuhiro Fujii, Koji Ohara, Takashi Taniguchi and Osami Sakata. Structure and properties of densified silica glass: characterizing the order within disorder. NPG Asia Materials volume 12, 85 (2020). https://doi.org/10.1038/s41427-020-00262-z
Akihiko Hirata, Tomohide Wada, Ippei Obayashi and Yasuaki Hiraoka. Structural changes during glass formation extracted by computational homology with machine learning. Communications Materials 1, 98 (2020). https://doi.org/10.1038/s43246-020-00100-3
Chihiro Koyama, Shuta Tahara, Shinji Kohara, Yohei Onodera, Didrik R. Småbråten, Sverre M. Selbach, Jaakko Akola, Takehiko Ishikawa, Atsunobu Masuno, Akitoshi Mizuno, Junpei. T. Okada, Yuki Watanabe, Yui Nakata, Koji Ohara, Haruka Tamaru, Hirohisa Oda, Ippei Obayashi, Yasuyuki Hiraoka, and Osami Sakata. Very sharp diffraction peak in non-glass forming liquid with the formation of distorted tetraclusters. NPG Asia Materials 12, 43, (2020). https://doi.org/10.1038/s41427-020-0220-0
Emi Minamitani, Takuma Shiga, Makoto Kashiwagi, and Ippei Obayashi. Relationship between local coordinates and thermal conductivity in amorphous carbon. Journal of Vacuum Science & Technology A 40, 033408 (2022). https://doi.org/10.1116/6.0001744
Yohei Onodera, Yasuyuki Takimoto, Hiroyuki Hijiya, Taketoshi Taniguchi, Shingo Urata, Seiji Inaba, Sanae Fujita, Ippei Obayashi, Yasuaki Hiraoka and Shinji Kohara. Origin of the mixed alkali effect in silicate glass. NPG Asia Materials 11 75 (2019). https://doi.org/10.1038/s41427-019-0180-4
Yohei ONODERA, Shinji KOHARA, Shuta TAHARA, Atsunobu MASUNO, Hiroyuki INOUE, Motoki SHIGA, Akihiko HIRATA, Koichi TSUCHIYA, Yasuaki HIRAOKA, Ippei OBAYASHI, Koji OHARA, Akitoshi MIZUNO, and Osami SAKATA. Understanding diffraction patterns of glassy, liquid and amorphous materials via persistent homology analyses. Journal of the Ceramic Society of Japan 2019 127(12) 853–863, (2019). (article (open access))
M. Murakami, S. Kohara, N. Kitamura, J. Akola, H. Inoue, A. Hirata, Y. Hiraoka, Y. Onodera, I. Obayashi, J. Kalikka, N. Hirao, T. Musso, A. S. Foster, Y. Idemoto, O. Sakata, and Y. Ohishi. Ultrahigh-pressure form of SiO2 glass with dense pyrite-type crystalline homology. Phys. Rev. B 99, 045153 (2019). (article)
M. Kimura, I. Obayashi, Y. Takeichi, R. Murao, and Y. Hiraoka. Non-empirical identification of trigger sites in heterogeneous processes using persistent homology. Scientific Reports 8, 3553, (2018). (article (open access))
Takashi Ichinomiya, Ippei Obayashi, and Yasuaki Hiraoka. Persistent homology analysis of craze formation. Phys. Rev. E 95, 012504, (2017) . (article)
Life science
Yohei Shimizu, Takanori Kurokawa, Hirokazu Arai, Hitoshi Washizu. Higher-order structure of polymer melt described by persistent homology: Applications to the atomic data of polymer copmuted by MD simulations
Fumihiko Uesugi, Masashi Ishii. Classification for transmission electron microscope images from different amorphous states using persistent homology: TEM image analysis with ML
Sungyeon Hong, Donghun Kim. Medium-range order in amorphous ices revealed by persistent homology
Developmental biology
QCD (quantum chromodynamics)