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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
JAEA-Technology-2017-026.pdf:4.0MB
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 10
Gy 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; Shibata, Hiroshi; Otsuka, Noriaki; Uehara, Toshiaki; Tsuchiya, Kunihiko; Shibagaki, Taro*; Komanome, Hirohisa*
IEEE Transactions on Nuclear Science, 63(5), p.2698 - 2702, 2016/10
Times Cited Count：3 Percentile：27.98(Engineering, Electrical & Electronic)In response to the lesson of the accident at the Fukushima Dai-ichi Nuclear Power Plant, we started a development of a radiation-resistant in-water wireless transmission system. In this study, capability of light emitting diodes (LED) and photo diodes (PD) as light emitting and receiving devices was researched. Results of irradiation tests of LEDs and PDs up to 1 MGy indicated a main cause of the degradation of the optical performances of the diodes was not the radiation damage at the semiconductor parts but the coloring of the resin parts. Assuming that the use of the candidate LED and PD, the PD's output current generated by the emission light of the LED at five meters away in water was estimated to be detectable intensity even considering the effects of the absorption of the light by water and the increased dark current by 1 MGy irradiation. Therefore, a radiation resistant in-water transmission system can be constructed using LEDs and PDs in principle.
Otsuka, Noriaki; Takeuchi, Tomoaki; Shibagaki, Taro*; Komanome, Hiroshi*; Tsuchiya, Kunihiko
Proceedings of Decommissioning and Remote Systems 2016 (D&RS 2016) (CD-ROM), p.277 - 278, 2016/07
no abstracts in English
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.
-irradiation effects on imaging sensors in radiation-resistant monitoring cameraTakeuchi, Tomoaki; Ueno, Shunji; Shibata, Hiroshi; Tsuchiya, Kunihiko; Kamiyanagi, Tomohiro*; Komanome, Hirohisa*; Watanabe, Takashi*
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
-ray degradation of light emitting and receiving devices for in-water wireless transmission systemShibata, Hiroshi; Hanakawa, Hiroki; Takeuchi, Tomoaki; Ueno, Shunji; Uehara, Toshiaki; Tsuchiya, Kunihiko; Araki, Masanori; Shibagaki, Taro*; Komanome, Hirohisa*
no journal, ,
no abstracts in English
