Faculty Profiles - SHINBORI Atsuki

Response of ionospheric electric fields at mid-low latitudes during sudden commencements Reviewed

N. Takahashi, Y. Kasaba, A. Shinbori, Y. Nishimura, T. Kikuchi, Y. Ebihara, T. Nagatsuma

JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS Vol. 120 ( 6 ) page： 4849 - 4862 2015.6

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

Using in situ observations from the Republic of China Satellite-1 spacecraft, we investigated the time response and local time dependence of the ionospheric electric field at mid-low latitudes associated with geomagnetic sudden commencements (SCs) that occurred from 1999 to 2004. We found that the ionospheric electric field variation associated with SCs instantaneously responds to the preliminary impulse (PI) signature on the ground regardless of spacecraft local time. Our statistical analysis also supports the global instant transmission of electric field from the polar region. In contrast, the peak time detected in the ionospheric electric field is earlier than that of the equatorial geomagnetic field (similar to 20s before in the PI phase). Based on the ground-ionosphere waveguide model, this time lag can be attributed to the latitudinal difference of ionospheric conductivity. However, the local time distribution of the initial excursion of ionospheric electric field shows that dusk-to-dawn ionospheric electric fields develop during the PI phase. Moreover, the westward electric field in the ionosphere, which produces the preliminary reverse impulse of the geomagnetic field on the dayside feature, appears at 18-22h LT where the ionospheric conductivity beyond the duskside terminator (18h LT) is lower than on the dayside. The result of a magnetohydrodynamic simulation for an ideal SC shows that the electric potential distribution is asymmetric with respect to the noon-midnight meridian. This produces the local time distribution of ionospheric electric fields similar to the observed result, which can be explained by the divergence of the Hall current under nonuniform ionospheric conductivity.

DOI： 10.1002/2015JA021309

The capacity-building and science-enabling activities of the IUGONET for the solar-terrestrial research community Reviewed

Yatagai, A; Sato, Y; Shinbori, A; Abe, S; UeNo, S

EARTH PLANETS AND SPACE Vol. 67 ( 1 ) 2015.1

Language：English Publishing type：Research paper (scientific journal) Publisher：Earth, Planets and Space

Background: This paper presents an overview of the capacity-building activities and science-enabling services of the Inter-university Upper atmosphere Global Observation NETwork (IUGONET) project. This Japanese program, which started in 2009, is building a metadata database (MDDB) of ground-based observations and is developing an analysis software to handle the data linked to the MDDB system for use by the solar-terrestrial physics community. Because the institutional members of the IUGONET are mainly universities in Japan, we explore tools that can contribute to advanced education as well as promote research activities. Findings: In this paper, we describe the utilities of the IUGONET for education, including our capacity-building activities in developing countries. We have regularly facilitated training seminars for Japanese students on the use of our tools (IUGONET MDDB and the software), and we have held capacity-building seminars for young scientists in developing countries. In addition to the MDDB, we have prepared various 'gateway' tools for users who are unfamiliar with 'keywords' to search for data. One of these is a geographical display tool that uses Google Earth (KML file), which is included as supplemental material to this paper. The usefulness of the IUGONET has been proven over its first 5 years of operation by the increasing number of its users, which has led to the production of approximately 500 scientific papers, including 42 thesis papers. Conclusions: The IUGONET community collaborates with the Scientific Committee on Solar-Terrestrial Physics program, not only in its scientific activities, but also in the establishment of E-infrastructure and capacity building.

DOI： 10.1186/s40623-014-0170-2

Long-term variation in the upper atmosphere as seen in the geomagnetic solar quiet daily variation Reviewed

Thermal and low-energy ion outflows in and through the polar cap: The polar wind and the low-energy component of the cleft ion fountain Reviewed

Kitamura, N, K. Seki, Y. Nishimura, T. Abe, M. Yamada, S. Watanabe, A. Kumamoto, A. Shinbori, A. W. Yau

AGU Geophysical Monograph 2015

Shinbori, A; Koyama, Y; Nose, M; Hori, T; Otsuka, Y; Yatagai, A

EARTH PLANETS AND SPACE Vol. 66 ( 1 ) page： 1 - 20 2014.12

Language：English Publishing type：Research paper (scientific journal) Publisher：Earth, Planets and Space

Characteristics of long-term variation in the amplitude of solar quiet (Sq) geomagnetic field daily variation have been investigated using 1-h geomagnetic field data obtained from 69 geomagnetic observation stations within the period of 1947 to 2013. The Sq amplitude observed at these geomagnetic stations showed a clear dependence on the 10- to 12-year solar activity cycle and tended to be enhanced during each solar maximum phase. The Sq amplitude was the smallest around the minimum of solar cycle 23/24 in 2008 to 2009. The relationship between the solar F10.7 index and Sq amplitude was approximately linear but about 53% of geomagnetic stations showed a weak nonlinear relation to the solar F10.7 index. In order to remove the effect of solar activity seen in the long-term variation of the Sq amplitude, we calculated a linear or second-order fitting curve between the solar F10.7 index and Sq amplitude during 1947 to 2013 and examined the residual Sq amplitude, which is defined as the deviation from the fitting curve. As a result, the majority of trends in the residual Sq amplitude that passed through a trend test showed negative values over a wide region. This tendency was relatively strong in Europe, India, the eastern part of Canada, and New Zealand. The relationship between the magnetic field intensity at 100-km altitude and residual Sq amplitude showed an anti-correlation for about 71% of the geomagnetic stations. Furthermore, the residual Sq amplitude at the equatorial station (Addis Ababa) was anti-correlated with the absolute value of the magnetic field inclination. This implies movement of the equatorial electrojet due to the secular variation of the ambient magnetic field.

DOI： 10.1186/s40623-014-0155-1

An Interactive Data Language software package to calculate ionospheric conductivity by using numerical models Reviewed

Yukinobu Koyamaa, Atsuki Shinbori, Yoshimasa Tanaka, Tomoaki Hori, Masahito Nose, Satoshi Oimatsu

COMPUTER PHYSICS COMMUNICATIONS Vol. 185 ( 12 ) page： 3398 - 3405 2014.12

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCIENCE BV

The Inter-university Upper atmosphere Global Observation NETwork (IUGONET) project focuses on handling ground-based observational data of the upper atmosphere. To this end, the project members have been developing a data analysis software package which is based on Interactive Data Language (IDL). Filling the spatial gaps in observational data requires the use of numerical models. In this paper, we discuss an IDL software package for global ionospheric conductivity by integration of 3rd party numerical models. The model can be used to create further derived models. (C) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cpc.2014.08.011

Interuniversity Upper Atmosphere Global Observation NETwork (IUGONET) meta-database and analysis software Reviewed

Long-term variation in the upper atmosphere as seen in the geomagnetic solar quiet daily variation Reviewed

Shinbori, A, Y. Koyama, M, Nose, T. Hori, Y. Otsuka, A. Yatagai

Earth, Planets and Space Vol. 65 ( 155 ) 2014.12

The capacity-building and science-enabling activities of the IUGONET to the solar-terrestrial research community Reviewed

Yatagai, A, Y. Sato, A. Shinbori, S. Abe, S. UeNo, IUGONET Team

Earth, Planets and Space 2014.12

A. Yatagai, Y. Tanaka, S. Abe, A. Shinbori, M. Yagi, S. UeNo, Y. Koyama, N. Umemura, M. Nosé, T. Hori, Y. Sato, N. O. Hashiguchi, N. Kaneda

Data Science Journal Vol. 13 ( 0 ) page： PDA37 - PDA43 2014.10

Language：English Publishing type：Research paper (scientific journal) Publisher：Committee on Data for Science and Technology

An overview of the Interuniversity Upper atmosphere Global Observation NETwork (IUGONET) project is presented. This Japanese program is building a meta-database for ground-based observations of the upper atmosphere, in which metadata connected with various atmospheric radars and photometers, including those located in both polar regions, are archived. By querying the metadata database, researchers are able to access data file/information held by data facilities. Moreover, by utilizing our analysis software, users can download, visualize, and analyze upper-atmospheric data archived in or linked with the system. As a future development, we are looking to make our database interoperable with others.

DOI： 10.2481/dsj.IFPDA-07

CiNii Research

Progress of the IUGONET system - metadata database for upper atmosphere ground-based observation data Reviewed

Shuji Abe, Norio Umemura, Yukinobu Koyama, Yoshimasa Tanaka, Manabu Yagi, Akiyo Yatagai, Atsuki Shinbori, Satoru UeNo, Yuka Sato, Naoki Kaneda

EARTH PLANETS AND SPACE Vol. 66 ( 133 ) 2014.10

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

Background: The Interuniversity Upper atmosphere Global Observation NETwork (IUGONET) project is a 6-year research project which started in 2009. The objective of this project is to establish a metadata database of various ground-based observation data covering a wide region from the Sun to the Earth; this will encourage more studies on the mechanisms of long-term variations in the upper atmosphere.
Findings: For archiving purposes, the metadata database system for cross-searching various data distributed across many universities and institute was developed based on the existing repository software called DSpace as the core component and the Space Physics Archive Search and Extract (SPASE) data model as the metadata format. The IUGONET metadata database is still in operation since it was released in March 2012. The system is continuously examined, tested, and updated to improve its quality. The OpenSearch interface in the IUGONET metadata database allows the user to use external applications easily for exchanging metadata and/or for analyzing data.
Conclusions: We conducted self-examination of our product, which was added for planning future directions of the IUGONET project.

DOI： 10.1186/1880-5981-66-133

Application of associative search to the metadata database of the upper atmosphere Reviewed

KOYAMA Yukinori, ABE Shuji, YAGI Manabu, UMEMURA Norio, HORI Tomoaki, SHINBORI Atsuki, SATO Yuka, IYEMORI Toshihiko, TANAKA Yoshimasa, HASHIGUCHI Noriko, UENO Satoru, YATAGAI Akiyo

JAXA research and development report Vol. 13 page： 89 - 97 2014.3

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：宇宙航空研究開発機構

In order to understand the mechanism of global-scale phenomena in the upper atmosphere, multidisciplinary researches using many kinds of data are important. An infrastructure to access to many kinds of data on the Internet is one of the keys to the multidisciplinary researches. The Inter-university Upper atmosphere Global Observation NETwork (IUGONET) project solved this problem by developing a metadata database to provide information such as URL of database or each data .le, which are managed dispersively by several institutes. Because the metadata database covers a wide scienti.c .eld, it is likely that non-specialized users can not easily select a right search phrase. We connected an associative search engine which is called GETAssoc with the metadata database, in order to get the related words and to generate re-query phrases by using them automatically. We collected metadata from SAO/NASA Astrophysics Data System to create the dictionary for associative search. We show that the prepared dictionary gives the related terms as expected for generating re-query phrases.

CiNii Research

Analysis software for upper atmospheric data developed by the IUGONET project and its application to polar science Reviewed

Tanaka, Y.-M, A. Shinbori, T. Hori, Y. Koyama, S. Abe, N. Umemura, Y. Sato, M. Yagi, S. UeNo, A. Yatagai, Y. Ogawa, Y. Miyoshi

Advances in Polar Science, 24, 231-240, doi:10.3724/SP.J.1085.2013.00231 2013.12

Global distributions of storm-time ionospheric currents as seen in geomagnetic field variations Reviewed

Shinbori, A, T. Hori, Y. Tanaka, Y. Koyama, T. Kikuchi, T. Nagatsuma

Advances in Polar Science, 24, 296-314, doi:10.3724/SP.J.1085.2013.00296 Vol. 24 page： 296 - 314 2013.12

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

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

Data Science Journal Vol. 12 2013.4

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Data Science Journal

An overview of the Inter-university Upper atmosphere Global Observation NETwork (IUGONET) project is presented with a brief description of the products to be developed. This is a Japanese inter-university research program to build the metadata database for ground-based observations of the upper atmosphere. The project also develops the software to analyze the observational data provided by various universities/institutes. These products will be of great help to researchers in efficiently finding, obtaining, and utilizing various data dispersed across the universities/institutes. This is expected to contribute significantly to the promotion of interdisciplinary research, leading to more a comprehensive understanding of the upper atmosphere.

DOI： 10.2481/dsj.WDS-030

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

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