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Takeuchi, Tomoaki; Otsuka, Noriaki; Watanabe, Takashi*; Tanaka, Shigeo*; Ozawa, Osamu*; Komanome, Hirohisa*; Ueno, Shunji*; Tsuchiya, Kunihiko
Proceedings of 2017 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC 2017) (Internet), 3 Pages, 2018/11
no abstracts in English
Takeuchi, Tomoaki; Shibata, Hiroshi; Hanakawa, Hiroki; Uehara, Toshiaki*; Ueno, Shunji*; Tsuchiya, Kunihiko; Kumahara, Hajime*; Shibagaki, Taro*; Komanome, Hirohisa*
JAEA-Technology 2017-026, 26 Pages, 2018/02
Under severe accidents, high-integrity transmission techniques are necessary so as to monitor the situation of the nuclear power plant. In this study, effects of gamma irradiation up to 10Gy on properties of optical devices were evaluated toward the development of a radiation-resistant in-water wireless transmission system using visible light. After the irradiation, for the LEDs, the total luminous flux decreased and the browning of resin lenses occurred. Meanwhile, the current-voltage characteristics hardly changed. For the PDs, the light sensitivity decreased and the browning of resin window occurred. The dark currents of PDs did not become large enough to adversely affect transmission. These results indicated that both the decreases of the total luminous flux of the LEDs and the light sensitivity of the PDs were mainly caused by not the degradation of the semiconductor parts but the browning of the resin parts by the irradiation. In addition, basic decrease behaviors of light transmission of several different types of glasses by gamma irradiation were also obtained so as to select the suitable optical windows and filters for the developing radiation-resistant in-water wireless transmission system.
Takeuchi, Tomoaki; Otsuka, Noriaki; Tsuchiya, Kunihiko; Tanaka, Shigeo*; Ozawa, Osamu*; Komanome, Hirohisa*; Watanabe, Takashi*; Ueno, Shunji*
Nihon Hozen Gakkai Dai-13-Kai Gakujutsu Koenkai Yoshishu, p.391 - 394, 2016/07
no abstracts in English
Takeuchi, Tomoaki; Otsuka, Noriaki; Shibagaki, Taro*; Komanome, Hirohisa*; Ueno, Shunji*; Tsuchiya, Kunihiko
Nihon Hozen Gakkai Dai-13-Kai Gakujutsu Koenkai Yoshishu, p.379 - 386, 2016/07
no abstracts in English
Takeuchi, Tomoaki; Otsuka, Noriaki; Watanabe, Takashi*; Kamiyanagi, Tomohiro*; Komanome, Hirohisa*; Ueno, Shunji*; Tsuchiya, Kunihiko
Proceedings of Decommissioning and Remote Systems 2016 (D&RS 2016) (CD-ROM), p.263 - 264, 2016/07
In response to the lesson of the accident at the Fukushima Dai-ichi Nuclear Power Plant, we started a development of a radiation resistant monitoring camera system. In this study, improvement of radiation resistance of the imaging sensor was addressed as the main target. Three different types of CMOS image sensors with field plate structure and three transistors (3TPD), photogate structure and three (3TPG) or four transistors (4TPG) were designed and fabricated. The sensors were irradiated up to 70 kGy at the Co
-ray irradiation facility at Takasaki Advanced Radiation Research Institute in Japan Atomic Energy Agency. After irradiation, the dark current of the 4TPG rapidly increased and excessed that of the 3T types at least by 50 kGy. The large increase of the dark current of the 4TPG resulted in almost no sensitivity at least by 50 kGy. On the other hand, the sensitivities of the 3T types remained usable values and 3TPG had larger sensitivity than 3TPD after 50 kGy. As the results, the 3TPG sensor was revealed to be the most advantageous one in terms of dark current and sensitivity among the fabricated three sensors.
Takeuchi, Tomoaki; Hanakawa, Hiroki; Shibata, Hiroshi; Uehara, Toshiaki; Ueno, Shunji; Kumahara, Hajime*; Tsuchiya, Kunihiko
JAEA-Review 2014-050, JAEA Takasaki Annual Report 2013, P. 33, 2015/03
irradiation effects on LEDs and photo diodes (PDs) were evaluated toward the development of a radiation-resistant in-water wireless transmission system using visible light. The current-voltage characteristics and total luminous flux of the LEDs and the dark current and light sensitivity of the PDs were measured before and after the irradiation. After the irradiation, for the LEDs, the total luminous flux decreased and the resin lenses turned oxblood. Meanwhile, the current-voltage characteristics hardly changed. For the PDs, the light sensitivity decreased and the resin window turned oxblood while the dark currents stayed at most 10 nA. These results indicated that both the decreases of the total luminous flux of the LEDs and the light sensitivity of the PDs were mainly caused by not the degradation of the semiconductor parts but the coloring of the resin parts by the irradiation.
Takeuchi, Tomoaki; Ueno, Shunji; Komanome, Hirohisa*; Otsuka, Noriaki; Shibata, Hiroshi; Kimura, Nobuaki; Matsui, Yoshinori; Tsuchiya, Kunihiko; Araki, Masanori
Proceedings of 6th International Symposium on Material Testing Reactors (ISMTR-6) (Internet), 7 Pages, 2013/10
During the station blackout situation at the Fukushima Dai-ichi (1F) Nuclear Power Plant, conventional in-pile instrumentation systems did not work sufficiently, resulting in the progress of the severe accident. In June 2011, the Japanese government referred to "Enhancement of instrumentation to identify the status of the reactors and PCVs" as a lesson of the accident at the 1F NPP, in the report of Japanese government to the IAEA ministerial conference in accordance with such situation, we started from 2012 a research and development which corresponds to the provisions so as to monitor the NPPs situations during a severe accident. In this research and development, we have been building of technical bases of a radiation-resistant high-definition and high-sensitivity monitoring camera, a wireless transmission system, and radiation- and heat-resistant signal line. The objective and latest progress situations of the R&D including the results of the characteristic experiments will be introduced in this symposium.
Nisawa, Atsushi*; Yoneda, Yasuhiro; Ueno, Go*; Murakami, Hironori*; Okajima, Yuka*; Yamamoto, Kenichiro*; Semba, Yasunori*; Uesugi, Kentaro*; Tanaka, Yoshihito*; Yamamoto, Masaki*; et al.
Journal of Synchrotron Radiation, 20(2), p.219 - 225, 2013/03
Times Cited Count:12 Percentile:52.88(Instruments & Instrumentation)A Si(111) winged crystal has been designed to minimize anticlastic bending and improve sagittal focusing efficiency. The crystal was thin with wide stiffening wings. The length-to-width ratio of the crystal was optimized by finite element analysis, and the optimal value was larger than the "golden value". The analysis showed that the slope error owing to anticlastic bending is less than the Darwin width. The X-rays were focused two-dimensionally using the crystal and a tangentially bent mirror. The observed profiles of the focal spot agreed well with the results of a ray-tracing calculation in the energy range from 8 to 17.5 keV. X-ray diffraction measurements with a high signal-to-noise ratio using this focusing system were demonstrated for a small protein crystal.
Wada, Seiichi*; Khoa, T. V.*; Kobayashi, Yasuhiko; Funayama, Tomoo; Ogihara, Kikumi*; Ueno, Shunji*; Ito, Nobuhiko*
Journal of Veterinary Medical Science, 67(11), p.1089 - 1095, 2005/11
Times Cited Count:18 Percentile:63.72(Veterinary Sciences)no abstracts in English
武内 伴照; 上野 俊二; 柴田 裕司
柴垣 太郎*; 野沢 省吾*
【課題】光無線通信において、通信状態が変化した場合においても、受信側から送信側への情報伝送速度の変更指示を要さずに、安定したデータの通信を可能にする。 【解決手段】送信側には、情報を2次元コードに対応した光パターンで表示可能な表示手段と、送信情報を光パターンで表示させるための2次元符号化データに変換する手段と、送信情報を時系列データに変換する手段と、光パターンが時系列データに基づいて強度変調されるように、2次元符号化データと時系列データとを重畳する手段と、そのデータに基づいて前記表示手段を駆動する手段と、を有する送信装置100を設ける。受信側には、表示手段を撮影するカメラ210と、カメラが撮影した映像から光パターンを読取って送信情報を復元する手段と、光パターンの強度変調状態から送信情報を復元する手段と、を有する受信装置200を設ける。
Takeuchi, Tomoaki; Ueno, Shunji; Shibata, Hiroshi; Tsuchiya, Kunihiko; Kamiyanagi, Tomohiro*; Komanome, Hirohisa*; Watanabe, Takashi*
no journal, ,
no abstracts in English
Tsuchiya, Kunihiko; Takeuchi, Tomoaki; Ueno, Shunji; Araki, Masanori; Komanome, Hirohisa*
no journal, ,
no abstracts in English
Takeuchi, Tomoaki; Otsuka, Noriaki; Kamiyanagi, Tomohiro*; Watanabe, Takashi*; Komanome, Hirohisa*; Ueno, Shunji*; Tsuchiya, Kunihiko
no journal, ,
no abstracts in English
Shibata, Hiroshi; Hanakawa, Hiroki; Takeuchi, Tomoaki; Ueno, Shunji; Uehara, Toshiaki; Tsuchiya, Kunihiko; Araki, Masanori; Shibagaki, Taro*; Komanome, Hirohisa*
no journal, ,
no abstracts in English
Takeuchi, Tomoaki; Tanaka, Shigeo*; Watanabe, Takashi*; Otsuka, Noriaki; Ozawa, Osamu*; Komanome, Hirohisa*; Ueno, Shunji*; Tsuchiya, Kunihiko
no journal, ,
no abstracts in English
Takeuchi, Tomoaki; Shibata, Hiroshi; Ueno, Shunji; Uehara, Toshiaki; Tsuchiya, Kunihiko; Shibagaki, Taro*; Komanome, Hirohisa*
no journal, ,
no abstracts in English
Tanaka, Shigeo*; Ozawa, Osamu*; Watanabe, Takashi*; Takeuchi, Tomoaki; Otsuka, Noriaki; Ueno, Shunji*; Komanome, Hirohisa*; Tsuchiya, Kunihiko
no journal, ,
no abstracts in English