Search Results - "Tsugawa, Takuya"

Concentric waves and short-period oscillations observed in the ionosphere after the 2013 Moore EF5 tornado by Nishioka, Michi, Tsugawa, Takuya, Kubota, Minoru, Ishii, Mamoru

“…We detected clear concentric waves and short‐period oscillations in the ionosphere after an Enhanced Fujita scale (EF)5 tornado hit Moore, Oklahoma, U.S., on…”
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Temporal and Spatial Variations of Total Electron Content Enhancements During a Geomagnetic Storm on 27 and 28 September 2017 by Shinbori, Atsuki, Otsuka, Yuichi, Sori, Takuya, Tsugawa, Takuya, Nishioka, Michi

“…Temporal and spatial evolutions of total electron content (TEC) and electron density in the ionosphere during a geomagnetic storm that occurred on 27 and 28…”
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Solar activity dependence of medium-scale traveling ionospheric disturbances using GPS receivers in Japan by Otsuka, Yuichi, Shinbori, Atsuki, Tsugawa, Takuya, Nishioka, Michi

“…In order to reveal solar activity dependence of the medium-scale traveling ionospheric disturbances (MSTIDs) at midlatitudes, total electron content (TEC) data…”
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Statistical Behavior of Large‐Scale Ionospheric Disturbances From High Latitudes to Mid‐Latitudes During Geomagnetic Storms Using 20‐yr GNSS‐TEC Data: Dependence on Season and Storm Intensity by Shinbori, Atsuki, Otsuka, Yuichi, Sori, Takuya, Tsugawa, Takuya, Nishioka, Michi

“…To establish the statistical behavior of ionospheric TEC variations from high latitudes to mid‐latitudes during the main and recovery phases of geomagnetic…”
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Statistical analysis of ionospheric total electron content (TEC): long-term estimation of extreme TEC in Japan by Nishioka, Michi, Saito, Susumu, Tao, Chihiro, Shiota, Daikou, Tsugawa, Takuya, Ishii, Mamoru

“…Ionospheric total electron content (TEC) is one of the key parameters for users of radio-based systems, such as the Global Navigation Satellite System,…”
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A monitoring network for anomalous propagation of aeronautical VHF radio waves due to sporadic E in Japan by Hosokawa, Keisuke, Sakai, Jun, Tomizawa, Ichiro, Saito, Susumu, Tsugawa, Takuya, Nishioka, Michi, Ishii, Mamoru

“…We introduce a network observation of anomalous long-distance propagation of aeronautical navigation (NAV) very high-frequency (VHF) radio waves due to…”
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Statistical analysis of short-wave fadeout for extreme space weather event estimation by Tao, Chihiro, Nishioka, Michi, Saito, Susumu, Shiota, Daikou, Watanabe, Kyoko, Nishizuka, Naoto, Tsugawa, Takuya, Ishii, Mamoru

“…Solar flares trigger an increase in plasma density in the ionosphere including the D region, and cause the absorption of radio waves, especially in…”
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Propagation characteristics of sporadic E and medium-scale traveling ionospheric disturbances (MSTIDs): statistics using HF Doppler and GPS-TEC data in Japan by Matsushima, Ryo, Hosokawa, Keisuke, Sakai, Jun, Otsuka, Yuichi, Ejiri, Mitsumu K., Nishioka, Michi, Tsugawa, Takuya

“…We carried out a statistical analysis of the propagation characteristics of Es and Medium-Scale Traveling Ionospheric Disturbances (MSTIDs) by combining data…”
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Statistical analysis for EUV dynamic spectra and their impact on the ionosphere during solar flares by Nishimoto, Shohei, Watanabe, Kyoko, Jin, Hidekatsu, Kawai, Toshiki, Imada, Shinsuke, Kawate, Tomoko, Otsuka, Yuichi, Shinbori, Atsuki, Tsugawa, Takuya, Nishioka, Michi

“…The X-rays and extreme ultraviolet (EUV) emitted during solar flares can rapidly change the physical composition of Earth’s ionosphere, causing space weather…”
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Observation and characterization of traveling ionospheric disturbances induced by solar eclipse of 20 March 2015 using incoherent scatter radars and GPS networks by Panasenko, Sergii V., Otsuka, Yuichi, van de Kamp, Max, Chernogor, Leonid F., Shinbori, Atsuki, Tsugawa, Takuya, Nishioka, Michi

“…We present the results of a comprehensive study of traveling ionospheric disturbances (TIDs) occurring over Europe during the total solar eclipse of 20 March…”
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Rayleigh wave signature in ionograms induced by strong earthquakes by Maruyama, Takashi, Tsugawa, Takuya, Kato, Hisao, Ishii, Mamoru, Nishioka, Michi

“…After the magnitude 9.0 earthquake off the Pacific coast of Tohoku (near the east coast of Honshu, Japan), which occurred on 11 March 2011, an unusual…”
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Model-based reproduction and validation of the total spectra of a solar flare and their impact on the global environment at the X9.3 event of September 6, 2017 by Watanabe, Kyoko, Jin, Hidekatsu, Nishimoto, Shohei, Imada, Shinsuke, Kawai, Toshiki, Kawate, Tomoko, Otsuka, Yuichi, Shinbori, Atsuki, Tsugawa, Takuya, Nishioka, Michi

“…We attempted to reproduce the total electron content (TEC) variation in the Earth's atmosphere from the temporal variation of the solar flare spectrum of the…”
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Storm-induced plasma stream in the low-latitude to midlatitude ionosphere by Maruyama, Takashi, Ma, Guanyi, Tsugawa, Takuya

“…Geomagnetic disturbances from 7 to 12 November 2004 were quite intense, and the maximum excursion of Dst reached −374 nT. Unusual ionospheric phenomena have…”
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Space weather benchmarks on Japanese society by Ishii, Mamoru, Shiota, Daikou, Tao, Chihiro, Ebihara, Yusuke, Fujiwara, Hitoshi, Ishii, Takako, Ichimoto, Kiyoshi, Kataoka, Ryuho, Koga, Kiyokazu, Kubo, Yuki, Kusano, Kanya, Miyoshi, Yoshizumi, Nagatsuma, Tsutomu, Nakamizo, Aoi, Nakamura, Masao, Nishioka, Michi, Saito, Susumu, Sato, Tatsuhiko, Tsugawa, Takuya, Yoden, Shigeo

“…We surveyed the relationship between the scale of space weather events and their occurrence rate in Japan, and we discussed the social impact of these…”
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Monitoring of equatorial plasma bubbles using aeronautical navigation system: a feasibility study by Hosokawa, Keisuke, Saito, Susumu, Nakata, Hiroyuki, Lin, Chien-Hung, Lin, Jia-Ting, Supnithi, Pornchai, Tomizawa, Ichiro, Sakai, Jun, Takahashi, Toru, Tsugawa, Takuya, Nishioka, Michi, Ishii, Mamoru

“…It has long been known that field-aligned irregularities within equatorial plasma bubbles (EPBs) can cause long-range propagation of radio waves in the VHF…”
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First observations of large-scale wave structure and equatorial spread F using CERTO radio beacon on the C/NOFS satellite by Thampi, Smitha V., Yamamoto, Mamoru, Tsunoda, Roland T., Otsuka, Yuichi, Tsugawa, Takuya, Uemoto, Jyunpei, Ishii, Mamoru

“…First observations of large‐scale wave structure (LSWS) and the subsequent development of equatorial spread F (ESF), using total electron content (TEC) derived…”
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Ionospheric peak height at the magnetic equator: Comparison between ionosonde measurements and IRI by Maruyama, Takashi, Ma, Guanyi, Tsugawa, Takuya, Supnithi, Pornchai, Komolmis, Tharadol

“…The ionospheric peak height in the F layer (hmF2) varies with not only thermospheric conditions but also dynamic processes in the upper atmosphere. At…”
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Direct Observations of Traveling Ionospheric Disturbances as Focusers of Solar Radiation: Spectral Caustics by Koval, Artem, Chen, Yao, Tsugawa, Takuya, Otsuka, Yuichi, Shinbori, Atsuki, Nishioka, Michi, Brazhenko, Anatoliy, Stanislavsky, Aleksander, Konovalenko, Aleksander, Zhang, Qing-He, Monstein, Christian, Gorgutsa, Roman

“…The solar radiation focusing effect is related to the specific phenomenon of propagation of the Sun-emitted HF and VHF waves through terrestrial ionosphere…”
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Temporal and Spatial Variations of Storm Time Midlatitude Ionospheric Trough Based on Global GNSS‐TEC and Arase Satellite Observations by Shinbori, Atsuki, Otsuka, Yuichi, Tsugawa, Takuya, Nishioka, Michi, Kumamoto, Atsushi, Tsuchiya, Fuminori, Matsuda, Shoya, Kasahara, Yoshiya, Matsuoka, Ayako, Ruohoniemi, J. Michael, Shepherd, Simon G., Nishitani, Nozomu

“…Temporal and spatial variations of the midlatitude ionospheric trough during a geomagnetic storm on 4 April 2017 have been investigated using Global Navigation…”
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Prediction of radiation pneumonitis using dose-volume histogram parameters with high attenuation in two types of cancer: A retrospective study by Uchida, Yasuki, Tsugawa, Takuya, Tanaka-Mizuno, Sachiko, Noma, Kazuo, Aoki, Ken, Fukunaga, Kentaro, Nakagawa, Hiroaki, Kinose, Daisuke, Yamaguchi, Masafumi, Osawa, Makoto, Nagao, Taishi, Ogawa, Emiko, Nakano, Yasutaka

“…The constraint values of dose-volume histogram (DVH) parameters for radiation pneumonitis (RP) prediction have not been uniform in previous studies. We…”
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