Adjoint-based data assimilation for reconstruction of thermal convection in a highly viscous fluid from surface velocity and temperature snapshots

A Nakao, T Kuwatani, S Ito… - Geophysical Journal …, 2024 - academic.oup.com
It is a general problem in geoscience to estimate the time-series of velocity and temperature
fields for a fluid based on limited observations, such as the flow velocity at the fluid surface …

Exploration of nonlinear parallel heterogeneous reaction pathways through Bayesian variable selection

RX Oyanagi, T Kuwatani, T Omori - The European Physical Journal B, 2021 - Springer
Inversion is a key method for extracting nonlinear dynamics governed by heterogeneous
reaction that occur in parallel in the natural sciences. Therefore, in this study, we propose a …

Bayesian inference of grain growth prediction via multi-phase-field models

S Ito, H Nagao, T Kurokawa, T Kasuya, J Inoue - Physical Review Materials, 2019 - APS
We propose a Bayesian inference methodology to evaluate unobservable parameters
involved in multi-phase-field models to accurately predict the observed grain growth, such …

Bayesian modeling of the equation of state for liquid iron in Earth's outer core

T Matsumura, Y Kuwayama, K Ueki… - Journal of …, 2021 - Wiley Online Library
We use Bayesian modeling of the equation of state (EoS) to constrain the density (ρ) and P
wave velocity (VP) of liquid iron under conditions of Earth's outer core. Experiments at such …

Multiple kinetic parameterization in a reactive transport model using the exchange Monte Carlo method

R Oyanagi, A Okamoto, N Tsuchiya - Minerals, 2018 - mdpi.com
Water–rock interaction in surface and subsurface environments occurs in complex
multicomponent systems and involves several reactions, including element transfer. Such …

Forecasting temporal variation of aftershocks immediately after a main shock using Gaussian process regression

K Morikawa, H Nagao, S Ito, Y Terada… - Geophysical Journal …, 2021 - academic.oup.com
Uncovering the distribution of magnitudes and arrival times of aftershocks is a key to
comprehending the characteristics of earthquake sequences, which enables us to predict …

[PDF][PDF] Adjoint-based marker-in-cell data assimilation for constraining thermal and flow processes from Lagrangian particle records

A Nakao, T Kuwatani, S Ito, H Nagao - Authorea Preprints, 2024 - essopenarchive.org
Geophysical problems often involve Lagrangian particles that follow surrounding flows and
record information about the system, such as the pressure and temperature path recorded in …

Estimating regression errors without ground truth values

H Tiittanen, E Oikarinen, A Henelius… - arXiv preprint arXiv …, 2019 - arxiv.org
Regression analysis is a standard supervised machine learning method used to model an
outcome variable in terms of a set of predictor variables. In most real-world applications we …

岩石形成プロセス抽出のための可視化情報計測

桑谷立 - 可視化情報学会誌, 2020 - jstage.jst.go.jp
抄録 岩石形成に関する物理化学的過程 (プロセス) を抽出するためには, 計測・分析により対象から
最大限に定量的データを抽出するとともに, 得られたデータから定量的なモデリングを通じて本質的な …