Faculty Profiles - SHINBORI Atsuki

Inter-university upper atmosphere global observation network (IUGONET) Reviewed

H. Hayashi, Y. Koyama, T. Hori, Y. Tanaka, S. Abe, A. Shinbori, M. Kagitani, T. Kouno, D. Yoshida, S. UeNo, N. Kaneda, M. Yoneda, N. Umemura, H. Tadokoro, T. Motoba

Data Science Journal Vol. 12 page： WDS179 - WDS184 2013.4

Language：English Publishing type：Research paper (scientific journal) Publisher：Ubiquity Press Ltd

DOI： 10.2481/dsj.WDS-030

ＩＵＧＯＮＥＴメタデータ登録・管理システムの処理性能評価 Reviewed

堀智昭, 梅村宜生, 阿部修司, 小山幸伸, 田中良昌, 林寛生, 林寛生, 上野悟, 新堀淳樹, 佐藤由佳, 八木学

宇宙航空研究開発機構研究開発報告 JAXA-RR- ( 12-006 ) page： 71 - 78 2013.3

Performance study of IUGONET metadata management system Reviewed

HORI Tomoaki, UEMURA Norio, ABE Shuji, KOYAMA Yukinobu, TANAKA Yoshimasa, HAYASHI Hiroo, UENO Satoru, SHINBORI Atsuki, SATO Yuka, YAGI Manabu

JAXA research and development report Vol. 12 page： 71 - 78 2013.3

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Aerospace Exploration Agency

This paper reports on the benchmark test of the metadata management system developed by the Inter-university Upper atmosphere Global Observation NETwork (IUGONET) project. The IUGONET metadata management system consists of the metadata reception module based on file repositories of Git, which is a widely-used version control software, and the metadata import module to register metadata to the metadata database using the DSpace commands. We made the performance assessments for these two modules in terms of the processing speed for registering/importing metadata both on a native Linux platform and a virtualized Linux platform. As a result, the metadata reception module processes properly eve millions of registered metadata within several minutes at most, showing roughly the similar performance for the native and virtualized platform. On the other hand, the metadata import module needs much longer processing times of several to a few tens of hours for the same amount of metadata. As compared with the virtualized platform, the native platform gives a four times faster speed for updating indices for the built-in search engine based on Lucene. From a perspective of the regular operation of the metadata management system, the metadata import module runs more efficiently on the native Linux platform and it is estimated by our performance test that it takes about 5 hours to newly import 105 metadata files and subsequently takes about 21 hours to update the Lucene indices for the registered metadata of 5 × 106 in total.

CiNii Research

Current status and future development of IUGONET data analysis software Reviewed

Tanaka Yoshimasa, Shinbori Atsuki, Umemura Norio, Hori Tomoaki, Abe Shuji, Koyama Yukinobu, Hayashi Hiroo, Ueno Satoru, Sato Yuka, Yatagai Akiyo, Ogawa Yasunobu, Miyoshi Yoshizumi, Seki Kanako, Miyashita Yukinaga, Segawa Tomonori

JAXA research and development report Vol. 12 page： 63 - 70 2013.3

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Aerospace Exploration Agency

In the IUGONET (Inter-university Upper atmosphere Global Observation NETwork) project, we have developed UDAS (iUgonet Data Analysis Software), which is a software to visualize and analyze various kinds of upper atmospheric data distributed by five universities/institutes (Tohoku Univ., Nagoya Univ., Kyoto Univ., Kyushu Univ., and NIPR). UDAS is a plug-in software of TDAS (THEMIS Data Analysis Software suite) written in IDL (Interactive Data Language), and thus can call useful routines to visualize and analyze time series data and GUI included in TDAS. We released a beta version of UDAS at the IUGONET website in May, 2011, and a formal version in February, 2012. We are planning to incorporate UDAS into TDAS and release it from the THEMIS software website after September, 2012. Automatic test tools for the UDAS programs were developed to reduce the workload for the development team. Furthermore, we built an executable file of TDAS that can run on the IDL Virtual Machine environment without any IDL licenses and released it for public testing. These developments will contribute to the promotion of the use of the UDAS and the ground-based observational data distributed by the IUGONET institutions.

Current status and future development of IUGONET data analysis software Reviewed

JAXA research and development report Vol. 12 ( 12-006 ) page： 63 - 70 2013.3

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Aerospace Exploration Agency

CiNii Books

J-GLOBAL

Application of the associative searching system GETAssoc to the metadata database of the upper atmosphere

Inter-University upper Atmosphere Global Observation Network (IUGONET) Reviewed

Hayashi H., UeNo S., Kaneda N., Yoneda M., Umemura N., Tadokoro H., Motoba T., team IUGONET project, Koyama Y., Hori T., Tanaka Y., Abe S., Shinbori A., Kagitani M., Kouno T., Yoshida D.

Data Science Journal Vol. 12 ( 0 ) page： WDS179 - WDS184 2013

Language：English Publishing type：Research paper (scientific journal) Publisher：CODATA

DOI： 10.2481/dsj.WDS-030

IUGONET解析ソフトウェアの現状と今後の発展 Reviewed

田中良昌, 新堀淳樹, 梅村宜生, 堀智昭, 阿部修司, 小山幸伸, 林寛生, 上野悟, 佐藤由佳, 谷田貝亜紀代, 小川泰信, 三好由純, 関華奈子, 宮下幸長, 瀨川朋紀

宇宙科学情報解析論文誌 Vol. 2 page： 63 - 70 2013

Manabu YAGI, Yukinobu KOYAMA, Shuji ABE, Norio UMEMURA, Atsuki SHINBORI, Tomoaki HORI, Yoshimasa TANAKA, Satoru UeNo, Yuka SATO, Akiyo YATAGAI, and Ber, RITSCHEL

Proceedings of Forum on Data Engineering and Information Management page： A10-1 2013

Evolution of negative SI-induced ionospheric flows observed by SuperDARN King Salmon HF radar Reviewed

T. Hori, A. Shinbori, N. Nishitani, T. Kikuchi, S. Fujita, T. Nagatsuma, O. Troshichev, K. Yumoto, A. Moiseyev, K. Seki

JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS Vol. 117 ( 12 ) 2012.12

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER GEOPHYSICAL UNION

The spatial evolution of vortex-like flow structures induced by a negative sudden impulse (SI-) is studied on the basis of SuperDARN King Salmon HF radar (KSR) with other ground and satellite data. A large dip in the solar wind density induced a fairly large SI- with a SYM-H amplitude of similar to 40 nT. The SI- induced ionospheric flow signatures in the evening sector (MLT similar to 19 h) were observed by KSR as a westward flow associated with the preliminary impulse (PI) followed by a more intense eastward flow with the main impulse (MI) in the sub-auroral region of the magnetic latitude similar to 60-70 deg, consistent with the local ground magnetic field observations. Following the first PI-MI flow sequence, KSR saw a second and possibly third sequence of flow variation which were much smaller in flow amplitude than the first pair but showed qualitatively very similar flow variations and latitudinal/longitudinal propagation characteristics. These observations can be interpreted as aftershocks of the first PI-MI; the same sequence of vortices and field-aligned currents were generated and then drifted anti-sunward with the same mechanism, namely the pumping motion of the dayside magnetosphere. These results are qualitatively consistent with predictions suggested by recent numerical simulations. Citation: Hori, T., A. Shinbori, N. Nishitani, T. Kikuchi, S. Fujita, T. Nagatsuma, O. Troshichev, K. Yumoto, A. Moiseyev, and K. Seki (2012), Evolution of negative SI- induced ionospheric flows observed by SuperDARN King Salmon HF radar, J. Geophys. Res., 117, A12223, doi:10.1029/2012JA018093.

DOI： 10.1029/2012JA018093

Storm-time electron density enhancement in the cleft ion fountain Reviewed Open Access

N. Kitamura, Y. Nishimura, M. O. Chandler, T. E. Moore, N. Terada, T. Ono, A. Shinbori, A. Kumamoto

JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS Vol. 117 ( 11 ) 2012.11

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER GEOPHYSICAL UNION

To determine the characteristics and origin of observed storm-time electron density enhancements in the polar cap, and to investigate the spatial extent (noon-midnight direction) of associated O+ ion outflows, we analyzed nearly simultaneous observations of such electron density enhancements from the Akebono satellite and ion upflows from the Polar satellite during a geomagnetic storm occurring on 6 April 2000. The Akebono satellite observed substantial electron density enhancements by a factor of similar to 10-90 with a long duration of similar to 15 h at similar to 2 R-E in the southern polar region. The Polar satellite outflow measurements in the northern polar cap at similar to 7-4 R-E exhibited velocity filtering of the similar to 100 eV to similar to 0 eV (from the spacecraft potential) ion outflow from the cleft ion fountain, with resultant temperatures declining from similar to 3 eV to 0.03 eV with increasing distance from the cusp. Similar velocity filtering was detected in the southern polar cap at similar to 1.8-3.5 RE. The region of O+ ion outflows with fluxes exceeding 5 x 10(8) /cm(2)/s (mapped to 1000 km altitude) extended similar to 10 degrees MLAT (similar to 1000 km) at the ionosphere from the cusp/cleft into the dayside polar cap at similar to 2.5 RE. These coordinated Akebono-Polar observations are consistent with the development of storm-time electron density enhancements in the polar cap as a result of the bulk outflow of low-energy plasma as part of the cleft ion fountain. The large spatial scale, large ion fluxes, and the long duration indicate significant supply of very-low-energy O+ ions to the magnetosphere through this region.

DOI： 10.1029/2012JA017900

Magnetic local time and latitude dependence of amplitude of the main impulse (MI) of geomagnetic sudden commencements and its seasonal variation Reviewed

Atsuki Shinbori, Yuji Tsuji, Takashi Kikuchi, Tohru Araki, Akihiro Ikeda, Teiji Uozumi, Dmitry Baishev, Boris M. Shevtsov, Tsutomu Nagatsuma, Kiyohumi Yumoto

JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS Vol. 117 ( 8 ) 2012.8

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER GEOPHYSICAL UNION

The magnetic local time and latitude dependence of amplitude of the main impulse (MI) of geomagnetic sudden commencements (SCs) and its seasonal variation have been investigated using high time resolution (1-3 sec) geomagnetic data in the latitudinal range 27-70 degrees for the period 1996-2010. The daytime distribution of the SC-MI amplitude in the sub-auroral and middle latitudes (35-60 degrees) is similar to the DP-2 type geomagnetic variation which shows negative and positive changes in the morning and afternoon, respectively. The magnetic field variation is reversed around the magnetic latitude of 63-65 degrees. This suggests that a pair of field-aligned currents (FACs), resembling the region-1 (R-1) FACs, is located near the magnetic latitude of 63-65 degrees. The nighttime SC amplitude is enhanced significantly in the low and middle latitudes (27-60 degrees). The enhancement is due to the magnetic effect produced by the SC-MI FACs. In the nighttime auroral latitude (63-65 degrees), the SC amplitude decreases steeply due to the enhanced westward auroral electrojet associated with the compression of the magnetosphere. The size of the diurnal variation tends to increase significantly during the summer, compared with that during the winter. This seasonal variation suggests that the DP-2 type ionospheric currents (ICs) and FACs generated during the SC-MI phase are intensified by increased ionospheric conductivities during the summer. It can be concluded that the large-scale MI current system in the ionosphere and magnetosphere is voltage generator.

DOI： 10.1029/2012JA018006

Magnetic latitude and local time distributions of ionospheric currents during a geomagnetic storm Reviewed Open Access

Yuji Tsuji, Atsuki Shinbori, Takashi Kikuchi, Tsutomu Nagatsuma

JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS Vol. 117 ( 7 ) 2012.7

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER GEOPHYSICAL UNION

In order to clarify the global distribution of ionospheric currents during a geomagnetic storm, we analyzed ground magnetic disturbances from high latitudes to the magnetic equator for the storm on September 7-8, 2002, with the minimum SYM-H value of -168 nT. In this analysis, we investigated magnetic field deviations in the northward component from the SYM-H, as functions of the dipole magnetic latitude (DMLAT) and the magnetic local time (MLT). During the main phase of the storm, the deviations at the low latitudes (10 degrees-35 degrees in DMLAT) were positive/negative in the dawn/dusk (0-9/11-24 h MLT) sector. On the other hand, the deviations at the dayside middle latitudes (35 degrees-55 degrees in DMLAT) were negative/positive in the morning/afternoon (6-12/13-15 h MLT) sector. The local time distribution at the low latitudes may represent the dawn-dusk asymmetry of the storm time ring current, while that at the dayside middle latitudes coincides with the DP2 currents due to the convection electric field associated with the Region 1 field-aligned currents (R1 FACs). All over the nightside middle latitude, the deviations were positive. This implies the direct effect of the R1 FACs through the Biot-Savart's law. At the geomagnetic equator, the eastward and westward electrojets were intensified on the day and nightside, respectively, being caused by the penetrated dawn-to-dusk convection electric field. We found that the MLT distribution of the magnetic deviations during the recovery phase was in opposite sense to that during the main phase at the dayside middle latitudes. The reversed magnetic disturbances must be due to the overshielding electric field associated with the Region 2 field-aligned currents (R2 FACs). Similarly, the deviations at the dayside and nightside equator were reversed, indicating penetration of the dusk-to-dawn overshielding electric field into the equatorial ionosphere. Based on the above results, we propose a current system including the ionospheric currents at middle latitudes caused by the R1/R2 FACs, equatorial EEJ/CEJ, and asymmetric ring current, during the main/recovery phase of the geomagnetic storm.

DOI： 10.1029/2012JA017566