Research Interests

研究内容

Mathematical modeling of earthquake fault mechanics

地震発生物理学の数理モデリング

Dynamic rupture of earthquake faults lying along and intersecting with a material interface

Detail

Seismic waves are reflected and refracted at interfaces of dissimilar rocks, such as strata and plate boundaries, just as light is reflected at the the water surface. We analyze theoretically, using differential and integral equations and computer simulations, what is different and how earthquakes become more complicated when the fault rupture extends around the interfaces compared to the case without the interface.

媒質境界近傍の断層における地震時の動的破壊伝播

詳細

地層やプレート境界など, 異なる岩石が接する境界では, 光が空気中から水面へ入射するときと同じように, 地震波も反射や屈折を生じます. その周辺で地震が起き, 断層の破壊が拡大するとき, 境界が無い場合と比べて何が異なるのか, 地震はどのように複雑化するのか, 微分・積分方程式やコンピュータシミュレーションを用いて理論的に解析します.

Mechanisms of rupture velocity/direction

Detail

The rupture propagation within rocks during an earthquake accelerates instantly and spreads across the fault plane at a speed of more than 2 km per second. However, unlike woods or glass, which break to the edge of the material in most cases, the fault rupture propagation always slows down and finally stops. On the other hand, the rupture is not always in all directions. The speed and direction of rupture varies by events, and it is still veiled what mechanism is behind it.

破壊伝播の速度や方向が決まるメカニズム

詳細

地震時の岩石の破壊は, 一瞬で加速して, 秒速 2 km 以上のスピードで断層面を拡がります. しかし割り箸やガラスがほとんどの場合に材料の端まで割れるのとは違い, 断層の破壊拡大は必ず減速し, どこかで停止します. 一方で, 破壊が拡がる方向は四方八方とは限りません. このスピードや方向は地震のたびに様々で, どのようなメカニズムに従うのか, 完全には分かっていません.

Slip/stress heterogeneity, energy release, and foreshock-mainshock-aftershock sequences

Detail

After an earthquake, a slip of several meters may appear on the ground surface, and this slip is the true nature of the earthquake. Even when the slip is not visible on the ground surface, it occurs on the fault plane in deep underground . The slip amount is heterogeneous and shows a complex distribution. We are interested in how this distribution relates to the energy release of earthquakes and complex seismic activities with foreshocks and aftershocks.

滑りや応力の不均質とエネルギー解放, 前震-本震-余震系列の関係

詳細

地震後, 地表に数 m のずれが現われることがあり, このずれが地震の正体です. あるいは地表に見られなくても, ずれは地下深くで生じており, 断層面に沿って岩石が滑った痕跡です. この滑りの量は一回の地震においても場所ごとに異なり, 複雑な分布を示します. この分布が, 地震のエネルギー解放や, 前震・余震を伴なう複雑な地震活動とどう関係するのかが興味の対象です.

Source time functions based on a stochastic differential equation

Detail

Fault slip during an earthquake accelerates from a resting state to a few m/s and finally stops again. The process of this acceleration, analyzed from the seismic waves, yields a complicated and various time series. Despite the complexity, their statistical and empirical laws have been obtained, and we have found that a stochastic differential equation, also used in economics and other fields, effectively represents the process mathematically.

確率微分方程式を用いた震源時間関数のモデル化

詳細

地震時の断層滑りは, 停止状態から数 m/s 程度まで加速した後, 最終的には再び停止します. その経過を地震波から求めると, 非常に複雑で, かつ地震ごとに多様な, 個性豊かな関数が得られます. しかし複雑ながらも統計的な経験則は得られており, 数学的にそれを表現するには, 経済学などでも用いられる確率微分方程式という道具が有効であることが分かってきました.

Methodology for seismic data analysis

地震波形データ解析の手法改良

Objective threshold for similar earthquake detection based on the extreme value theory and an information criterion

Detail

Small earthquakes are numerous and provide a wealth of information. To find tiny tremors caused by them, we have to search for waveforms similar to known seismic waveforms from a large amount of seismograph data. This requires much data processing and a criterion for determining how similar the waveforms are to those of a known earthquake. We are developing new algorithms and software to speed up the processing and studying theories based on statistics and information science for the determination.

極値統計と情報量規準に基づく, 地震波形相関法における客観的な閾値決定

詳細

小地震は数が多く, そこから得られる情報も豊富です. 小地震による微弱な揺れを見つけるため, 膨大な地震計のデータから, 既知の地震波形と似た波形を探すことがあります. そのためには大量のデータ処理と, どの程度似ていれば地震と判定するかの根拠が求められます. 処理を高速化するため新たなアルゴリズムとソフトウェアの開発を, 判定のため統計学・情報科学に基づく理論の研究を進めます.

Seismic event-pair detection by Deep hashing

Detail

Seismic waveforms differ in various ways depending on the position and orientation of the fault and its relationship with the observation points. If we can classify similar seismic waveforms by assigning short labels, we can immediately compare them with similar earthquakes in the past when new waveforms were obtained. These labels are called hash values, and we have shown that deep learning can contribute to finding a function that efficiently assigns hash values to various waveforms.

深層学習ハッシュ関数による相似地震検知

詳細

断層の位置や向き, および観測点との位置関係によって, 地震波形は様々に異なります. その中で類似の地震波形に短いラベルを付けて分類することができれば, 新たな波形が得られたとき, 過去のよく似た地震と直ちに比較することができます. このラベルをハッシュ値と呼び, 多様な波形に効率的にハッシュ値を割り当てる関数を探すため, 深層学習を利用できることを示しました.

Laboratory seismology

実験地震学

Dynamic opening/shear rupture in a photoelastic medium

Detail

Strong stresses act on rocks during an earthquake, causing widespread dynamic rupture. Since it is difficult to observe the distribution of stresses inside a rock during the rupture, we use materials that allow us to “watch” the stresses. The strength of the stresses inside the rock can be visualized by transmitting light through acrylic or agar and passing via a polarizing filter. Using this technique, we will observe the distribution of stresses when a material ruptures and discuss fault behavior.

光弾性媒質中の動的開口/せん断破壊

詳細

地震時には岩石に大きな力が作用し, 破壊が拡がります. その直前や最中に岩石内部の力の分布を計測することは難しいので, 力を「視る」ことが可能な材料を使います. アクリルや寒天などに光を透過させ, 偏光板というフィルタを通すと, 内部に作用している力の強弱が可視化されます. この技術を用いて, 材料が破壊する際の力の分布を観察し, 断層運動について考察します.

Academic Positions & Education

経歴

Assistant professor, May. 2024 -- present

助教, 2024年05月 -- 現在

Department of Global Environment and Disaster Prevention Sciences, Faculty of Science and Technology, Hirosaki University, Japan

弘前大学大学院 理工学研究科 地球環境防災学コース

Teaching Seismology etc.

担当科目: 地震学I, 地球環境学演習I etc.

Assistant professor, Apr. 2015 -- Apr. 2024

助教, 2015年04月 -- 2024年04月

Department of Physical Science, College of Science and Engineering, Ritsumeikan University, Japan

立命館大学 理工学部 物理科学科

Teaching Earth Science/Laboratory Works in Earth Science

担当科目: (教養)地球科学, 宇宙地球科学1, 地学実験, 物理学実験実習 etc.

Postdoctoral fellow, Oct. 2013 -- Mar. 2015

ポスト・ドクター研究員, 2013年10月 -- 2015年03月

Mega Quake Risk Management Project / Faculty of Engineering, Information and Systems, Tsukuba University, Japan

筑波大学「巨大地震による複合災害の統合的リスクマネジメント」プロジェクト

PhD course, Apr. 2009 -- Sep. 2013

博士後期課程 2009年04月 -- 2013年09月

Earthquake Research Institute / Department of Earth and Planetary Science, Graduate School of Science, University of Tokyo, Japan

東京大学大学院 理学系研究科 地球惑星科学専攻 / 東京大学地震研究所

supervised by Teruo Yamashita and Nobuki Kame

指導教員: 山下輝夫, 亀伸樹

Internship, Jul. 2011 -- Aug. 2011

海外インターン, 2011年07月 -- 2011年08月

School of Engineering and Applied Science, Harvard University, U.S.

research assistant of James R. Rice

Master's course, Apr. 2007 -- Mar. 2009

博士前期課程, 2007年04月 -- 2009年03月

Earthquake Research Institute / Department of Earth and Planetary Science, Graduate School of Science, University of Tokyo, Japan

東京大学大学院 理学系研究科 地球惑星科学専攻 / 東京大学地震研究所

supervised by Teruo Yamashita

指導教員: 山下輝夫

Undergraduate course, Apr. 2003 -- Mar. 2007

学士課程, 2003年04月 -- 2007年03月

Department of Mathematics, Faculty of Science Division I, Tokyo University of Science, Japan

東京理科大学 理学部I部 数学科

supervised by Keiichi Kato

指導教員: 加藤圭一

Publications

出版物

Submitted manuscripts

Hirano, S., & Naoi, M. (under review)

DiallelX: a modern fortran code for calculating network cross-correlation

Naoi, M., Hirano, S., & Chen, Y. (under review)

High-resolution monitoring of hydraulically induced acoustic emission activities using neural phase picking and matched filter analysis

Peer-reviewed journal papers

Naoi, M., & Hirano, S.. (2024)

Efficient similar waveform search using short binary codes obtained through a deep hashing technique

Geophys. J. Int., 273(1):607--621, doi:10.1093/gji/ggae061

Yagi, Y., Okuwaki, R., Hirano, S., Enescu, B., Chikamori, M., & Yamaguchi, R. (2024)

Barrier-induced rupture front disturbances during the 2023 Morocco earthquake

Seismol. Res. Lett., 95(3):1591--1598, doi:10.1785/0220230357

Ohara, K., Yagi, Y., Yamashita, S., Okuwaki, R., Hirano, S., & Fukahata, Y. (2023)

Complex evolution of the 2016 Kaikoura earthquake revealed by teleseismic body waves

Prog. Earth Planet. Sci., 10:35, doi:10.1186/s40645-023-00565-z

Hirano, S., Kawakata, H. & Doi, I. (2022)

A matched-filter technique with an objective threshold

Sci. Rep., 12:22090, doi:10.1038/s41598-022-25839-2

大嵜雅人, 吉光奈奈, 平野史朗, 福山英一 (EN: Osaki, M., Yoshimitsu, N., Hirano, S., & Fukuyama, E.) (2022)

注水による誘発地震発生場を模擬した寒天ゲルを用いた光弾性実験手法 (EN: Photoelastic experimental approach using agar gel to simulate a stress field of fluid injection induced earthquakes)

地震 第2輯 (Zisin: Journal of Seismological Society of Japan), 75:83--91, doi:10.4294/zisin.2021-17 (Japanese text with English abstract.)

Hirano, S. (2022)

Source time functions of earthquakes based on a stochastic differential equation

Sci. Rep., 12:3936, doi:10.1038/s41598-022-07873-2

Numerical results in an ascii format: OSF: Open Science Framework, doi:10.17605/OSF.IO/VUXJ6

Nakayama, M., Kawakata, H., Hirano, S., & Doi, I. (2021)

Development of a laboratory monitoring system for elastic waves transmitted through sand under dry and saturated conditions

Earth Planet Space, 73(25), doi:10.1186/s40623-020-01346-4

Hirano, S., & Itou, H. (2020)

Parameter interdependence of dynamic self-similar crack with distance-weakening friction

Geophys. J. Int., 223(3):1584--1596, doi:10.1093/gji/ggaa392

Erratum

eq. (7) must be $L(x) = \displaystyle \log\left|\frac{1-x}{1+x}\right|$ (absolute value symbol was missing)

$\Delta \sigma_b$ in eqs.(C1)(C5)(C6)(C7) and next line to eq.(C9) must be $\sigma_b$.

Okuwaki, R., Hirano, S., Yagi, Y., & Shimizu, K. (2020)

Inchworm-like source evolution through a geometrically complex fault fueled persistent supershear rupture during the 2018 Palu Indonesia earthquake

Earth Planet. Sci. Lett., 547(2020):116449, doi:10.1016/j.epsl.2020.116449

EarthArXiv Preprints, doi:10.31223/osf.io/j4cas

OSF: Open Science Framework, doi:10.17605/OSF.IO/8AZ3G

Hirano, S. (2019)

Modeling of unilateral rupture along very-long reverse faults

J. Geophys. Res., 124(1):1057--1071, doi:10.1029/2018JB016511.

Okuwaki, R., Kasahara, A., Yagi, Y., Hirano, S. & Fukahata, Y. (2019)

Backprojection to image slip

Geophys. J. Int., 216(3):1529--1537, doi:10.1093/gji/ggy505.

Tamaribuchi, K., Yagi, Y., Enescu, B. & Hirano, S. (2018)

Characteristics of foreshock and aftershock activity inferred from the JMA earthquake catalog improved by automatic processing

Earth Planet Space, 70:90, doi:10.1186/s40623-018-0866-9.

Hirano, S. & Yagi, Y. (2017)

Dependence of seismic and radiated energy on shorter wavelength components

Geophys. J. Int., 209(3):1585--1592, doi:10.1093/gji/ggx108.

Hirano, S. & Yamashita, T. (2016)

Modeling of interfacial dynamic slip pulses with slip-weakening friction

Bull. Seism. Soc. Am. 106(4):1628--1636, doi: 10.1785/0120150208.

Erratum

$\displaystyle \frac{1}{1+S}$ in eqs. (19)(20)(22) must be $\displaystyle - \frac{1}{1+S}$ (minus sign was missing)

Self archive of a pre-copyedit version

Hirano, S. & Yamashita, T. (2015)

Dynamic anti-plane rupture propagation crossing a material interface: modelling with BIEM

Geophys. J. Int. 200(2):1220--1233, doi:10.1093/gji/ggu471.

Erratum

eq. (26) must be $\Psi_l(X) = \displaystyle \sqrt{X^2-\beta_l^{-2}} \arctan{\frac{\eta_l}{\sqrt{X^2-\beta_l^{-2}}}} - \eta_l$ (subscript $l$ of $\beta$ was missing)

Okuwaki, R., Yagi, Y. & Hirano, S. (2014)

Relationship between High-frequency Radiation and Asperity Ruptures, Revealed by Hybrid Back-projection with a Non-planar Fault Model

Sci. Rep., 4:7120, doi:10.1038/srep07120.

Yagi, Y., Okuwaki, R., Enescu, B., Hirano, S., Yamagami, Y., Endo, S. & Komoro, T. (2014)

Rupture process of the 2014 Iquique Chile earthquake in relation with the foreshock activity

Geophys. Res. Lett., 41(12):4201--4206, doi: 10.1002/2014GL060274.

Hirano, S. & Yamashita, T. (2011)

Analysis of the static stress field around faults lying along and intersecting a bimaterial interface

Geophys. J. Int. 187(3):1460--1478, doi:10.1111/j.1365-246X.2011.05202.x.

Peer-reviewed proceeding or departmental bulletin papers

Hirano, S. (2020)

Friction vs. damage: dynamic self-similar crack growth revisited

In: Itou, H. et al. (eds) Mathematical Analysis of Continuum Mechanics and Industrial Applications III. CoMFoS18. Mathematics for Industry, Springer, doi:10.1007/978-981-15-6062-0_12

Self archive of a pre-copyedit version

Nakayama, M., Kawakata, H., Hirano, S., Doi, I., & Takahashi, N. (2018)

Propagation characteristics of elastic waves transmitted through sand soils under dry and saturated conditions

Progress in Acoustic Emission XIX, Jpn. Soc. Non-Destructive Inspection, 163--167.

Hirano, S. (2018)

Integral representation and its applications in earthquake mechanics: a review

In: van Meurs, P. et al. (eds) Mathematical Analysis of Continuum Mechanics and Industrial Applications II. CoMFoS 2016. Mathematics for Industry, vol 30. Springer, Singapore, doi:10.1007/978-981-10-6283-4_9.

Self archive of a pre-copyedit version

Endo, S., Nakao, A., Hirano, S. & Yagi, Y. (2017)

The 2013 Sea of Okhotsk deep earthquake: A complex rupture within the Ringwoodite stability zone

Earth Evol. Sci., 11:23--30.

Hirano, S. (2017)

Propagation velocity of pulse-like rupture along earthquake faults

In: Itou, H. et al. (eds) Mathematical Analysis of Continuum Mechanics and Industrial Applications. Mathematics for Industry, vol 26. Springer, Singapore, doi:10.1007/978-981-10-2633-1_10.

Self archive of a pre-copyedit version

Book

Itou, H., Hirano, S., Kimura, M., Kovtunenko, V.A., & Khludnev, A.M. (Eds.) (2020)

Mathematical Analysis of Continuum Mechanics and Industrial Applications III. CoMFoS18. Mathematics for Industry, Springer, doi:10.1007/978-981-15-6062-0

Misc.

Hirano, S., & Okuwaki, R. (2020)

Note on “Backprojection to image slip”

OSF: Open Science Framework, doi:10.17605/OSF.IO/PB7HK

桑野修, 平野史朗, 藤田哲史, 日下部哲也, 小寺祐貴, 亀伸樹, 中谷正生, 安藤亮輔 (2011)

寒天（アガロースゲル）を用いた断層の動的破壊実験

日本地震学会ニュースレター Vol.22 No.6, 表紙

International Conferences

国際会議発表

Ichibe, Y., Kawakata, H., & Hirano, S.

Relationship between the source time function and imaging reliability in synthetic receiver function analysis

American Geophysical Union 2024 Fall Meeting, Washington D.C., U.S., December 13, 2024 (Poster)

Hirano, S.

Physics of a stochastic partial differential equation for kinematic rupture modeling

American Geophysical Union 2024 Fall Meeting, Washington D.C., U.S., December 12, 2024 (Poster)

Yasumoto, R., Kawakata, H., & Hirano, S.

Effect of bay topography on an Lg wave —Numerical approach—

American Geophysical Union 2024 Fall Meeting, Washington D.C., U.S., December 12, 2024 (Poster)

Sasaki, M., Kawakata, H., & Hirano, S.

Spatio-temporal variation of seismicity in the Noto Peninsula region using long-term continuous seismograms of nearby stations

American Geophysical Union 2024 Fall Meeting, Washington D.C., U.S., December 11, 2024 (Poster)

Hirano, S.

Modeling of slip on a fault during an earthquake: point-source approximation

RIMS Workshop "Some approaches on ill-posed problems -theory and practice-", Kyoto, Japan, January 11, 2024 (Oral)

Yasumoto, R., Hirano, S., & Kawakata, H.

Effect of bay topography on surface waves

American Geophysical Union 2023 Fall Meeting, San Francisco, December 12, 2023 (Poster)

Inanishi, T., Kwakata, H., & Hirano, S.

Source parameters of AE events in uniaxial compression tests of cement mortar specimens

American Geophysical Union 2023 Fall Meeting, San Francisco, December 12, 2023 (Poster)

Hirano, S.

Stochastic source time functions with double corner frequencies

American Geophysical Union 2023 Fall Meeting, San Francisco, December 11, 2023 (Poster)

Hirano, S.

Statistics and variability of source time functions based on a stochastic differential equation

American Geophysical Union 2021 Fall Meeting, New Orleans and Online, December, 2021 (Oral)

Okuwaki, R., Yagi, Y., Shimizu, K., Fukahata, Y., Hirano, S., Hicks, S.P., Craig, T.J., Fan, W., Goes, S.D.B., & Wright, T.J.

Accounting epistemic uncertainty in finite-fault inversion: development of a potency-density tensor approach to investigate complex earthquake rupture processes

American Geophysical Union 2021 Fall Meeting, New Orleans and Online, December, 2021 (Oral, Invited)

Hirano, S.

Various inverse problems in seismology: seismic tomography, hypocenter location, earthquake source kinematics, and Earth's crustal stress.

Control and inverse problems on waves, oscillations and flows - Mathematical analysis and computational methods -, Online, September, 2021 (Oral)

Hirano, S.

Theoretical properties of source time functions based on a stochastic differential equation

Joint Scientific Assembly IAGA-IASPEI 2021, Online, August 26, 2021 (Flash talk & Poster)

Okuwaki, R., Hirano, S., Yagi, Y., & Shimizu, K.

Source evolution through a geometrically complex fault system controls supershear rupture during the 2018 Palu earthquake

FRINGE 2021 (Advances in the Science and Applications of SAR Interferometry and Sentinel-1 InSAR), Online, May 31--June 04, 2021 (Oral)

Hirano, S., & Itou, H.

Dynamic antiplane self-similar crack with distance-weakening friction: an analytical solution for source parameter estimation

American Geophysical Union 2020 Fall Meeting, Online, December 16, 2020 (Flash talk & Poster)

Go to the poster page.

Hirano, S.

An empirical PDE for slip along earthquake faults

The Second Russia-Japan Workshop "Mathematical analysis of fracture phenomena for elastic structures and its applications" - 20th Conference of Continuum Mechanics Focusing on Singularities (CoMFoS20), Online, December 15, 2020 (Oral)

Hirano, S.

A nonlinear integro-differential equation for earthquake faulting

RIMS Workshop on Analysis of inverse problems through partial differential equations and related topics, Kyoto, Japan, January 09, 2020 (Oral)

Hirano, S.

An observation-based differential equation of spatio-temporal slip distribution

American Geophysical Union 2019 Fall Meeting, San Francisco, U.S., December 13, 2019 (Poster)

Kakutani, T., Kawakata, H., & Hirano, S.

Seismic response change of a sand soil after strong motion, revealed by a transmission laboratory experiment

American Geophysical Union 2019 Fall Meeting, San Francisco, U.S., December 11, 2019 (Poster)

Nakayama, M., Kawakata, H., Hirano, S., & Doi, I.

Propagation characteristic changes of elastic waves transmitted through a sand soil in water injection and drainage processes

American Geophysical Union 2019 Fall Meeting, San Francisco, U.S., December 10, 2019 (Poster)

Hirano, S.

Dynamic growth of a self-similar anti-plane crack during earthquakes

Russia-Japan Workshop "Mathematical analysis of fracture phenomena for elastic structures and its applications", Novosibirsk, Russia, November 12, 2019 (Oral)

Hirano, S.

Energy dissipation during dynamic antiplane self-similar crack growth

CoMFoS19:Mathematical Analysis of Continuum Mechanics and Industrial Applications, Kanazawa, Japan, July 15, 2019 (Oral)

Hirano, S.

Analytical solution of dynamic self-similar crack growth under distance-weakening friction

Numerical Modeling of Earthquake Motions: Waves and Ruptures, Smolenice, Slovakia, July 01--03, 2019 (Poster)

Hirano, S., Kawakata, H., & Doi, I.

Foreshock activity detection by a threshold-free matched-filter technique

Japan Geoscience Union Meeting, Chiba, Japan, May 26, 2019 (Oral)

Hirano, S.

Aftershocks and the GR law due to a heterogeneous slip model

American Geophysical Union 2018 Fall Meeting, Washington D.C., U.S., December 14, 2018 (Oral)

Nakayama, M., Kawakata, H., Hirano, S., Doi, I., & Takahashi, N.

24-hours broadband measurements of elastic waves transmitted through sand soils under dry and saturated conditions to investigate differences in propagation characteristics

American Geophysical Union 2018 Fall Meeting, Washington D.C., U.S., December 10, 2018 (Poster)

Nakayama, M., Kawakata, H., Hirano, S., Doi, I., & Takahashi, N.

Propagation characteristics of elastic waves transmitted through sand soils under dry and saturated conditions

24th International Acoustic Emission Symposium, Sapporo, Japan, November 07, 2018 (Oral)

Hirano, S., Toyomoto, Y., Kawakata, H., & Doi, I.

Application of Extreme Value Theory to a Matched-Filter Analysis

10th ACES International Workshop, Awaji Island, Japan, September 27, 2018 (Poster)

Hirano, S.

Friction vs. damage: dynamic self-similar crack growth revisited

CoMFoS18:Mathematical Analysis of Continuum Mechanics and Industrial Applications, Kyoto, Japan, June 13, 2018 (Oral)

Hirano, S., Toyomoto, Y., Kawakata, H. & Doi, I.

Objective matched-filter analysis for dertecting small events

International Symposium on Earthquake Forecast / 5th International Workshop on Earthquake Preparation Process, ~Observation, Validation, Modeling, Forecasting~, Chiba, Japan, May 25, 2018 (Poster)

Wakamatsu, S., Kawakata, H. & Hirano, S.

Observed seismic and infrasonic signals around the Hakone volcano -Discussion based on a finite-difference calculation-

American Geophysical Union 2017 Fall Meeting, New Orleans, U.S., December 15, 2017 (Poster)

Hirano, S.

Mathematical modeling and numerical simulation of unilateral dynamic rupture propagation along very-long reverse faults

American Geophysical Union 2017 Fall Meeting, New Orleans, U.S., December 14, 2017 (Poster)

Nakayama, M., Kawakata, H., Hirano, S., Doi, I. & Takahashi, N.

Improvement in transmission experiment of elastic waves through partially saturated porous sand soil

American Geophysical Union 2017 Fall Meeting, New Orleans, U.S., December 14, 2017 (Poster)

Yoneda, N., Kawakata, H., Hirano, S., Yoshimitsu, N. & Takahashi, N.

Extraction of AE events to estimate their b values under a triaxial compressive condition ~Examination using continuous broadband records~

American Geophysical Union 2017 Fall Meeting, New Orleans, U.S., December 14, 2017 (Poster)

Hirano, S.

Unilateral dynamic rupture propagation along earthquake faults

CoMFoS17:Mathematical Analysis of Continuum Mechanics and Industrial Applications, OIST, Japan, September 21, 2017 (Oral)

Hirano, S.

Energy estimation of earthquake faulting based on a wavefield inversion

RIMS workshop on "Singularity and asymptotic behavior of solutions for partial differential equations with conservation law", Kyoto, Japan, June 08, 2017 (Oral)

Hirano, S.

Integral equation for mechanics of earthquakes

RIMS workshop on "Inverse problems for partial differential equations and related areas", Kyoto, Japan, January 26, 2017 (Oral)

Nakayama, M., Kawakata, H., Hirano, S., Doi, I., & Takahashi, N.

Transmission experiment of elastic waves with short wavelengths through a highly porous sand soil during water injection

American Geophysical Union 2016 Fall Meeting, San Francisco, U.S., December 15, 2016 (Poster)

Toyomoto, Y., Kawakata, H., Hirano, S. & Doi, I.

Foreshock search over a long duration using a method of setting appropriate criteria

American Geophysical Union 2016 Fall Meeting, San Francisco, U.S., December 15, 2016 (Poster)

Tsujimura, Y., Kawakata, H., Fukuyama, E., Yamashita, F., Xu, S., Mizoguchi, K, Takizawa, S. & Hirano, S.

Spatio-temporal foreshock activity during stick-slip experiments of large rock samples

American Geophysical Union 2016 Fall Meeting, San Francisco, U.S., December 13, 2016 (Poster)

Hirano, S., Yamashita, T. & Hatano, T.

Behavior of pulse-like rupture with velocity-time-dependent friction from a granular layer model

American Geophysical Union 2016 Fall Meeting, San Francisco, U.S., December 12, 2016 (Oral)

Hirano, S.

Integral representation and its applications of the mechanics of earthquakes

CoMFoS16:Mathematical Analysis of Continuum Mechanics and Industrial Applications, Kyushu University, Japan, October 23, 2016 (Oral)

Hirano, S. & Yamashita, T.

Propagation velocity of pulse-like rupture with a time-weakening friction law

American Geophysical Union 2015 Fall Meeting, San Francisco, U.S., December 18, 2015 (Poster)

Iwata, K., Kawakata, H., Hirano, S., & Doi, I.

Estimation of Seismic Attenuation beneath Tateyama Volcano, Central Japan by Using Peak Delay

American Geophysical Union 2015 Fall Meeting, San Francisco, U.S., December 17, 2015 (Poster)

Imahori, A., Kawakata, H., Hirano, S., Yoshimitsu, N., & Takahashi, N.

Travel Times of Later Phases for Transmitting Waves through a Fracturing Westerly Granite Sample under a Triaxial Compressive Condition

American Geophysical Union 2015 Fall Meeting, San Francisco, U.S., December 16, 2015 (Poster)

Hirano, S.

Propagation velocity of pulse-like rupture along earthquake fault

CoMFoS15:Mathematical Analysis of Continuum Mechanics and Industrial Applications, Kyushu University, Japan, November 16, 2015 (Oral)

Hirano, S. & Yagi, Y.

Dependence of seismic energy on higher wavenumber components

American Geophysical Union 2014 Fall Meeting, San Francisco, U.S., December 19, 2014 (Poster)

Yagi, Y., Okuwaki, R., Enescu, B. & Hirano, S.

Rupture process of the 2014 Iquique Chile earthquake in relation with the foreshock activity

American Geophysical Union 2014 Fall Meeting, San Francisco, U.S., December 17, 2014 (Poster)

Okuwaki, R., Yagi, Y. & Hirano, S.

Relationship between High-frequency Radiation and Asperity Rupture，Revealed by Hybrid Back-projection with Non-planer Fault

Seismological Society of America Annual Meeting, Anchorage, U.S., May 01, 2014 (Poster)

Hirano, S. & Yamashita, T.

BIEM Simulation for Anti-Plane Dynamic Rupture Propagation across a Bimaterial Interface

Seismological Society of America Annual Meeting, Anchorage, U.S., April 30, 2014 (Oral)

Hirano, S.

An integral representation and numerical simulation of dynamic earthquake faulting occurring in a two-layered medium

Conference on Diffusion in Heterogeneous Media and Related Topics, Tokyo, Japan, March 06, 2014 (Oral)

Hirano, S. & Yamashita, T.

Off Fault Stress Distribution around Dynamic Slip Pulse on a Bimaterial Interface

The 7th ACES International Workshop, Otaru, Japan, October 04, 2010 (Poster)

Hirano, S. & Yamashita, T.

Theoretical analysis of static mode-II crack in two-layered medium - interfacial fault and intersecting fault

Workshop -Earthquake Source Dynamics: Data and Data-constrained Numerical Modeling, Smolenice Castle, Slovakia, June 28, 2010 (Poster)

Hirano, S. & Yamashita, T.

Mathematical and numerical analysis of non-planar static mode-II crack in a two-layered medium

American Geophysical Union 2009 Fall meeting, San Francisco, U.S., December 17, 2009 (Poster)

Hirano, S. & Yamashita, T.

Mathematical and numerical analyses of arbitrarily oriented static mode-II crack in a two-layered medium

The 7th General Assembly of Asian Seismological Commission and The 2008 Fall meeting of Seismological Society of Japan, Tsukuba, Japan, November 27, 2008 (Poster)

Award & Grants

受賞・研究費採択

Award

受賞

Mar. 2019

2019年03月

The Young Scientist Award of Seismological Society of Japan for Extension of Mathematical Seismology

日本地震学会若手学術奨励賞 (受賞対象研究: 数理地震学の牽引と学際的な研究展開)

Grants

研究費採択

Apr. 2022 -- Mar. 2026

2022年04月 -- 2026年03月

Growth and termination of dynamic rupture revealed by a stochastic fault model

確率的震源モデルによって解き明かされる, 地震の成長と停止

The JSPS Grant-in-Aid for Scientific Research(C) Program No. 22K03782

科学研究費助成事業 基盤研究(C) 22K03782

Principal Investigator

研究代表者

Apr. 2022 -- Mar. 2026

2022年04月 -- 2026年03月

Elastodynamics for strongly heterogeneous material: experiment, numerical simulation, and theory

実験計測・数値計算・理論の融合による強い不均質を含む媒質に対する弾性波動論の構築

The JSPS Grant-in-Aid for Scientific Research(B) Program No. 23K22607

科学研究費助成事業 基盤研究(B) 23K22607

Co-Investigator (PI: Kawakata, H., Ritsumeikan Univ.)

研究分担者 (代表:川方裕則 立命館大学)

Apr. 2021 -- Mar. 2024

2021年04月 -- 2024年03月

Understanding the physics of foreshocks based on dense seismic observation and seismicity model

稠密地震観測データ解析と地震活動モデル構築による前震の意義の理解

The JSPS Grant-in-Aid for Scientific Research(B) Program No. 21H01191

科学研究費助成事業 基盤研究(B) 21H01191

Co-Investigator (PI: Naoi, M., Hokkaido Univ.)

研究分担者 (代表: 直井誠 北海道大学)

Apr. 2018 -- Mar. 2022

2018年04月 -- 2022年03月

SDE modeling for diversity and heterogeneity of earthquake ruptures

地震の個性や不均質を記述する確率微分方程式論的断層モデル

The JSPS Grant-in-Aid for Early-Career Scientists Program No. 18K13637

科学研究費助成事業 若手 18K13637

Principal Investigator

研究代表者

Apr. 2017 -- Mar. 2021

2017年04月 -- 2021年03月

Mathematical modeling and analysis of discontinuous phenomena in continuum body

連続体における不連続現象の数理モデリングと数学解析

The JSPS Grant-in-Aid for Scientific Research(B) Program No. 17H02857

科学研究費助成事業 基盤研究(B) 17H02857

Co-Investigator (PI: Kimura, M., Kanazawa Univ.)

研究分担者 (代表: 木村正人 金沢大学)

Societies & Contributions

学会・社会貢献活動

Scientific Societies

所属学会

American Geophysical Union

Japan Geoscience Union

日本地球惑星科学連合

Seismological Society of Japan

日本地震学会

The Japan Society for Industrial and Applied Mathematics (secretary of a research group Mathematical Aspects of Continuum Mechanics)

日本応用数理学会 (連続体力学の数理 研究部会幹事)

Journal Associate Editor

学術誌編集委員

Bulletin of the Japan Society for Industrial and Applied Mathematics (Jul. 2024 -- May. 2028)

応用数理 (2024年06月 -- 2028年05月)

Journal Reviewer

学術誌査読

Bulletin of Seismological Society of America

Computers and Mathematics with Applications

Earth Planets Space

Environmental Earth Sciences

European Journal of Environmental and Civil Engineering

Geophysical Journal International

Journal of Geophysical Research: Solid Earth

Journal of Japan Association for Earthquake Engineering

日本地震工学会論文集

Tectonophysics

Zisin: Jounrnal of the Seismological Society of Japan

地震 第2輯

Grant Reviewer

研究費審査員

Israel Science Foundation

Conference Management

学会大会・会議等委員

Program committee for The 10th International Congress on Industrial and Applied Mathematics. Waseda University, Tokyo, Japan, August 20--25, 2023

Organizing committee for CoMFoS18:Mathematical Analysis of Continuum Mechanics and Industrial Applications, Kyoto, Japan, June 13--15, 2018

Projects

プロジェクト

Earthquake and Volcano Hazards Observation and Research Program (Co-investigator, 2015-)

災害の軽減に貢献するための地震火山観測研究計画 (研究協力者, 2015-)

Mega Quake Risk Management project at University of Tsukuba (Postdoctoral fellow, 2013--2014)

筑波大学「巨大地震による複合災害の統合的リスクマネジメント」プロジェクト (ポスト・ドクター研究員, 2013--2014)

AE measurements in deep South African gold mines: Phase II - monitoring of rock mass damage by underground cavities and prediction of rockbursts (Research assistant, 2009-2011)

南アフリカ大深度鉱山での AE 計測第二期：地下空洞による岩盤損傷の監視と山跳ね予知 (リサーチアシスタント, 2009-2011)