著者

Munehiko Yamaguchi Hiromi Owada Udai Shimada Masahiro Sawada Takeshi Iriguchi Kate D. Musgrave Mark DeMaria

出版者

Meteorological Society of Japan

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

vol.14, pp.138-143, 2018 (Released:2018-10-06)

参考文献数

22

被引用文献数

1 14

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This study investigates prediction of TC intensity in the western North Pacific basin using a statistical-dynamical model called the Statistical Hurricane Intensity Prediction Scheme (SHIPS), with data sources in operations at the Japan Meteorological Agency (JMA) such as the JMA/Global Spectral Model forecast fields. In addition to predicting the change in the maximum wind (Vmax) as in the original SHIPS technique, another version of SHIPS for predicting the change in the minimum sea-level pressure (Pmin) has been developed. With 13 years of training samples, a total of 26 predictors were selected from among 52 through stepwise regression. Based on three years of independent samples, the root mean square errors of both Vmax and Pmin by the 26-predictor SHIPS model were found to be much smaller than those of the JMA/GSM and a simple climatology and persistence intensity model, which JMA official intensity forecasts are currently mainly based on. The prediction accuracy was not sensitive to the number of predictors as long as the leading predictors were included. Benefits of operationalizing SHIPS include a reduction in the errors of the JMA official intensity forecasts and an extension of their forecast length beyond the current 3 days (e.g., 5 days).

著者

Harumi Morioka Kiyoko Murata Tatsuki Sugisawa Mari Shibukawa Junya Ebina Masahiro Sawada Sayori Hanashiro Junpei Nagasawa Masaru Yanagihashi Takehisa Hirayama Masayuki Uchi Kiyokazu Kawabe Satoru Ebihara Yoshitaka Murakami Takashi Nakajima Osamu Kano

出版者

The Japanese Society of Internal Medicine

雑誌

Internal Medicine (ISSN:09182918)

巻号頁・発行日

vol.61, no.10, pp.1479-1484, 2022-05-15 (Released:2022-05-15)

参考文献数

28

被引用文献数

3

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Objective To assess the long-term effects of hybrid assistive limb (HAL) treatment on gait in patients with amyotrophic lateral sclerosis (ALS). Methods Three courses of treatment with HAL were administered to three women with ALS. Each course had a four- to five-week duration, during which the treatment was performed nine times, with a rest period of at least two months between each course. Gait ability (2-minutes-walk and 10-m-walk tests), ALS Functional Rating Scale-Revised, and respiratory function tests were performed before and after each treatment course. Patients Patients diagnosed with ALS, according to the updated Awaji criteria, by board-certified neurologists in the Department of Neurology and Department of Rehabilitation Medicine, Toho University Omori Faculty of Medicine between January and December 2019 were recruited. Results The average time from the start to the end of the 3 courses was 319.7±33.7 days. A multiple regression analysis was performed for the 2-minutes-walk and 10-m-walk tests, using the baseline value, each participant's ID, and time point as covariates. Changes after each course were considered outcomes. Following the 3 treatment courses, the 2-minutes walk distance improved by 16.61 m (95% confidence interval, -9.33-42.54) compared with the baseline value, but this improvement was not statistically significant (p=0.21). However, cadence significantly improved by 1.30 steps (95% confidence interval, 0.17-2.42; p=0.02). Conclusion Long-term, repetitive HAL treatments may help patients with ALS maintain their gait.

著者

Ryo OYAMA Masahiro SAWADA Kazuki SHIMOJI

出版者

Meteorological Society of Japan

雑誌

気象集誌. 第2輯 (ISSN:00261165)

巻号頁・発行日

vol.96B, pp.3-26, 2018 (Released:2018-03-16)

参考文献数

56

被引用文献数

8

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The high temporal and spatial resolutions of geostationary satellite observations achieved by recent technological advancements have facilitated the derivation of atmospheric motion vectors (AMVs), even in a tropical cyclone (TC) wherein the winds abruptly change. This study used TCs in the western North Pacific basin to investigate the ability of upper tropospheric AMVs to estimate the TC intensity and structure. We first examined the relationships between the cloud-top wind fields captured by 6-hourly upper tropospheric AMVs derived from images of the Multi-functional Transport Satellite (MTSAT) and the surface maximum sustained wind (MSW) of the Japan Meteorological Agency's best-track data for 44 TCs during 2011-2014. The correlation between the maximum tangential winds of the upper tropospheric AMVs (UMaxWinds) and MSWs was high, approximately 0.73, suggesting that the cyclonic circulation near the cloud top was intensified by the upward transport of absolute angular momentum within the TC inner core. The upper tropospheric AMVs also revealed that the mean radii of UMaxWinds and the maximum radial outflows shifted inward as the TC intensification rate became large, implying that the low-level inflow was strong for TCs undergoing rapid intensification. We further examined the possibility of estimating the MSW using 30-min-interval UMaxWinds derived from Himawari-8 target observations, which have been used to track TCs throughout their lifetimes. A case study considering Typhoon Lionrock (1610) showed that the UMaxWinds captured the changes in the cyclonic circulation near the cloud top within the inner core on a timescale shorter than 1 day. It was apparent that the increase in the UMaxWind was associated with the intensification of the TC warm core and the shrinkage of UMaxWind radius. These results suggest that Himawari-8 AMVs include useful information about TC intensification and related structural changes to support the TC intensity analysis and structure monitoring.

著者

Koji Terasaki Masahiro Sawada Takemasa Miyoshi

出版者

(公社)日本気象学会

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

vol.11, pp.23-26, 2015 (Released:2015-02-26)

参考文献数

14

被引用文献数

4 31

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The Local Ensemble Transform Kalman Filter (LETKF) is implemented with the Non-hydrostatic Icosahedral Atmospheric Model (NICAM) to assimilate the real-world observation data. First, the NICAM-LETKF system was developed using grid conversions between the NICAM's icosahedral grid and LETKF's uniform longitude-latitude grid to take advantage of the existing codes of Miyoshi. The grid conversions require additional computations and may cause additional interpolation error. Therefore, the LETKF code is modified, so that the LETKF reads and writes the NICAM's icosahedral grid data directly. We call this new version ICO-LETKF. In this study, the two systems are tested and compared using real conventional observations. The results show that the ICO-LETKF successfully accelerates the computations and improves the analyses.