195 citations · 711 across the 15 of their papers we have counts for
15 papers
Operational solar flare prediction model using Deep Flare Net
Naoto Nishizuka, Yuki Kubo, Komei Sugiura +2
We developed an operational solar flare prediction model using deep neural networks, named Deep Flare Net (DeFN). DeFN can issue probabilistic forecasts of solar flares in two cate…
Validation of Coronal Mass Ejection Arrival-Time Forecasts by Magnetohydrodynamic Simulations based on Interplanetary Scintillation Observations
Kazumasa Iwai, Daikou Shiota, Munetoshi Tokumaru +3
Coronal mass ejections (CMEs) cause various disturbances of the space environment; therefore, forecasting their arrival time is very important. However, forecasting accuracy is hin…
Reliable Probability Forecast of Solar Flares: Deep Flare Net-Reliable (DeFN-R)
Naoto Nishizuka, Yûki Kubo, Komei Sugiura +2
We developed a reliable probabilistic solar flare forecasting model using a deep neural network, named Deep Flare Net-Reliable (DeFN-R). The model can predict the maximum classes o…
A Comparison of Flare Forecasting Methods. IV. Evaluating Consecutive-Day Forecasting Patterns
Sung-Hong Park, K. D. Leka, Kanya Kusano +21
A crucial challenge to successful flare prediction is forecasting periods that transition between "flare-quiet" and "flare-active". Building on earlier studies in this series (Barn…
Spectral Structures of Type II Solar Radio Bursts and Solar Energetic Particles
Kazumasa Iwai, Seiji Yashiro, Nariaki V. Nitta +1
We investigated the relationship between the spectral structures of type II solar radio bursts in the hectometric and kilometric wavelength ranges and solar energetic particles (SE…
A Comparison of Flare Forecasting Methods. III. Systematic Behaviors of Operational Solar Flare Forecasting Systems
K. D. Leka, Sung-Hong Park, Kanya Kusano +21
A workshop was recently held at Nagoya University (31 October - 02 November 2017), sponsored by the Center for International Collaborative Research, at the Institute for Space-Eart…
A Comparison of Flare Forecasting Methods. II. Benchmarks, Metrics and Performance Results for Operational Solar Flare Forecasting Systems
K. D. Leka, Sung-Hong Park, Kanya Kusano +21
Solar flares are extremely energetic phenomena in our Solar System. Their impulsive, often drastic radiative increases, in particular at short wavelengths, bring immediate impacts…
Why do some probabilistic forecasts lack reliability?
Yûki Kubo
In this work, we investigate the reliability of the probabilistic binary forecast. We mathematically prove that a necessary, but not sufficient, condition for achieving a reliable…
Development of a coronal mass ejection arrival time forecasting system using interplanetary scintillation observations
Kazumasa Iwai, Daikou Shiota, Munetoshi Tokumaru +3
Coronal mass ejections (CMEs) cause disturbances in the environment of the Earth when they arrive at the Earth. However, the prediction of the arrival of CMEs still remains a chall…
Verification of operational solar flare forecast: Case of Regional Warning Center Japan
Yûki Kubo, Mitsue Den, Mamoru Ishii
In this article, we discuss a verification study of an operational solar flare forecast in the Regional Warning Center (RWC) Japan. The RWC Japan has been issuing four-categorical…
OCTAD-S: Digital Fast Fourier Transform Spectrometers by FPGA
Kazumasa Iwai, Yûki Kubo, Hiromitsu Ishibashi +5
We have developed a digital fast Fourier transform (FFT) spectrometer made of an analog-to-digital converter (ADC) and a field-programmable gate array (FPGA). The base instrument h…
Solar Flare Prediction Model with Three Machine-Learning Algorithms Using Ultraviolet Brightening and Vector Magnetogram
N. Nishizuka, K. Sugiura, Y. Kubo +3
We developed a flare prediction model using machine learning, which is optimized to predict the maximum class of flares occurring in the following 24 h. Machine learning is used to…
Interplanetary particle transport simulation for warning system for aviation exposure to solar energetic particles
Yûki Kubo, Ryuho Kataoka, Tatsuhiko Sato
Solar energetic particles (SEPs) are one of the extreme space weather phenomena. A huge SEP event increases the radiation dose received by aircrews, who should be warned of such ev…
Coronal Shock Waves, EUV Waves, and Their Relation to CMEs. III. Shock-Associated CME/EUV Wave in an Event with a Two-Component EUV Transient
V. V. Grechnev, A. N. Afanasyev, A. M. Uralov +5
On 17 January 2010, STEREO-B observed in extreme ultraviolet (EUV) and white light a large-scale dome-shaped expanding coronal transient with perfectly connected off-limb and on-di…
Effect of Finite Larmor Radius on the Cosmic Ray Penetration into an Interplanetary Magnetic Flux Rope
Yuki Kubo, Hironori Shimazu
We discuss a mechanism for cosmic ray penetration into an interplanetary magnetic flux rope, particularly the effect of the finite Larmor radius and magnetic field irregularities.…