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Terasaka, Yuta; Watanabe, Kenichi*; Uritani, Akira*
Hoshasen (Internet), 47(3), p.89 - 96, 2022/10
Terasaka, Yuta; Watanabe, Kenichi*; Uritani, Akira*; Yamazaki, Atsushi*; Sato, Yuki; Torii, Tatsuo; Wakaida, Ikuo
Journal of Nuclear Engineering and Radiation Science, 7(4), p.042002_1 - 042002_7, 2021/10
For the application in the measurement of the high dose rate hot spots inside the Fukushima Daiichi Nuclear Power Station (FDNPS) buildings, we propose a novel one-dimensional radiation distribution sensing method using an optical fiber sensor based on wavelength spectrum unfolding. The proposed method estimates the incident position of radiation to the fiber by the unfolding of the wavelength spectrum output from the fiber edge using the fact that the attenuation length of light along the fiber depends on the wavelength. Because this method measures the integrated light intensity, this method can avoid the problem of counting loss and signal pile-up, which occurs in the radiation detector with pulse counting mode under high dose rate field. Through basic experiments using the ultraviolet light source and Sr/Y radioactive point source, basic properties of source position detection were confirmed.
Terasaka, Yuta; Watanabe, Kenichi*; Uritani, Akira*
Nuclear Instruments and Methods in Physics Research A, 996, p.165151_1 - 165151_8, 2021/04
Times Cited Count:3 Percentile:46.8(Instruments & Instrumentation)For the measurement of radiation distribution inside the Fukushima Daiichi Nuclear Power Station (FDNPS) buildings, the evaluation of a small-diameter quartz optical fiber as a one-dimensional position-sensitive sensor was conducted. The sensor determines the incident position of radiation into the fiber using the time-of-flight information of emitted Cerenkov photons in the optical fiber. Compared with the conventional sensor using the plastic scintillating fiber, the quartz optical fiber has much higher position resolution, which may be the result of the improvement of timing characteristics caused by the prompt emission mechanism of the Cerenkov radiation. Additionally, the response of position-sensitive quartz optical fiber sensor under high radiation field was evaluated, and good count rate linearity was confirmed using the 10 m long quartz optical fiber with a diameter of 0.4 mm up to the dose rate at least 20 mSv/h, and the radiation tolerance property up to the accumulated dose of 1 kGy was evaluated.
Aoyagi, Kazuhei; Sakurai, Akitaka; Miyara, Nobukatsu; Sugita, Yutaka; Tanai, Kenji
Shigen, Sozai Koenshu (Internet), 6(2), 7 Pages, 2019/09
no abstracts in English
Kono, Masaru*; Hayama, Kazunori*; Matsui, Hiroya; Ozaki, Yusuke
JAEA-Technology 2019-011, 35 Pages, 2019/07
To verify long-term safety performance of the sensor for decades, we decided the extension of the collaborative research and the evaluation test of long-term durability of fiber-optic crack detection sensor developed by Tokyo Measuring Instruments Laboratory Co., Ltd. at the Mizunami Underground Research Laboratory were continued from FY 2015 to FY 2018. As a result, the measurement system using of the fiber-optic crack detection sensor is applicable for long-term measurement in deep underground area and find the future subject.
Nishimura, Akihiko; Yoshida, Minoru*; Yamada, Tomonori; Arakawa, Ryoki
Proceedings of International Topical Workshop on Fukushima Decommissioning Research (FDR 2019) (Internet), 3 Pages, 2019/05
JAEA support the development of remote sensing robotic system in the Naraha Remote Technology Development Center. A water tank is used as a mockup facility of nuclear reactor vessel. A compact seismic vibrometer based on an optical fiber interferometer is applied. A specially designed robotic system is also tested for installing the sensor unit. The experiment is prepared to clarify the transfer function of the water tank, using vibration noise of ground motion.
Kuwabara, Kazumichi*; Aoyagi, Yoshiaki; Ozaki, Yusuke; Matsui, Hiroya
JAEA-Research 2017-002, 39 Pages, 2017/03
Authors developed a displacement meter using optical fiber sensor. The displacement meter can be set at any locations in a borehole and guarantee the measurement accuracy up to 5MPa. Total twelve displacement meters were installed in three boreholes to measure the rock mass displacement during groundwater recovery test. The measurement of the rock mass displacement was stated on March, 27, FY 2014. During the first and second groundwater recovery experiments, compressive displacements were observed close to the closure test drift wall. Magnitude of the measured displacements, except vicinity of test drift wall, was smaller than that of calculated under the assumption of it is an isotropic elastic material.
Nishikawa, Hiroyuki*; Souno, T.*; Hattori, M.*; Oki, Y.*; Watanabe, E.*; Oikawa, Masakazu*; Arakawa, Kazuo; Kamiya, Tomihiro
JAERI-Review 2003-033, TIARA Annual Report 2002, p.254 - 256, 2003/11
no abstracts in English
Kobayashi, Tetsuya; Chishiro, Etsuji; Anami, Shozo*; Yamaguchi, Seiya*; Michizono, Shinichiro*
Proceedings of 28th Linear Accelerator Meeting in Japan, p.366 - 368, 2003/08
For the J-PARC linac, a 12-MHz RF reference is distributed to 60 low-level RF control systems of klystron stations through optical links. The error of the accelerating field must be within +/- 1 degree in phase and +/ 1% in amplitude. Thus, a very high phase stability (within +/- 0.3 degree in phase) is required to the reference distribution system. New optimized optical components for this linac were developed and the performance of them was tested. The results will be reported. In adition, the timing control signal distribution system for the linac will be illustlated.
To, Kentaro; Katagiri, Masaki; Sakasai, Kaoru; Matsubayashi, Masahito; Birumachi, Atsushi; Takahashi, Hiroyuki*; Nakazawa, Masaharu*
Applied Physics A, 74(Suppl.1), p.S1601 - S1603, 2002/12
Times Cited Count:6 Percentile:28.33(Materials Science, Multidisciplinary)no abstracts in English
Katagiri, Masaki; To, Kentaro; Sakasai, Kaoru; Matsubayashi, Masahito; Birumachi, Atsushi; Takahashi, Hiroyuki*; Nakazawa, Masaharu*
Applied Physics A, 74(Suppl.1), p.S1604 - S1606, 2002/12
Times Cited Count:6 Percentile:28.33(Materials Science, Multidisciplinary)no abstracts in English
Nishitani, Takeo; Shikama, Tatsuo*; Reichle, R.*; Sugie, Tatsuo; Kakuta, Tsunemi; Kasai, Satoshi; Ishitsuka, Etsuo; Yamamoto, Shin
Purazuma, Kaku Yugo Gakkai-Shi, 78(5), p.462 - 467, 2002/05
no abstracts in English
Nakazawa, Masaharu*; Takahashi, Hiroyuki*; Fukuda, Daiji*
JAERI-Tech 2002-019, 30 Pages, 2002/03
no abstracts in English
Katagiri, Masaki; Sakasai, Kaoru; Kishimoto, Maki; Nakamura, Tatsuya; To, Kentaro; Takahashi, Hiroyuki*; Nakazawa, Masaharu*
Nuclear Instruments and Methods in Physics Research A, 477(1-3), p.179 - 183, 2002/03
Times Cited Count:4 Percentile:29.4(Instruments & Instrumentation)no abstracts in English
Otsu, Iwao; Kondo, Masaya; Yonomoto, Taisuke; Anoda, Yoshinari
Nihon Kikai Gakkai 2001-Nendo Nenji Taikai Koen Rombunshu, Vol.1, p.7 - 8, 2001/00
no abstracts in English
Ogawa, Kazuhiko; Morita, Toshio*; Yanagisawa, Hiroshi; Aizawa, Eiju; Sakuraba, Koichi; Sugawara, Susumu; Ono, Akio
Journal of Nuclear Science and Technology, 37(12), p.1088 - 1097, 2000/12
no abstracts in English
Kakuta, Tsunemi; Yamagishi, Hideshi; Tabata, Hiroaki*; Urakami, Masao*
Dai-7-Kai Doryoku Enerugi Gijutsu Shimpojiumu Koen Rombunshu (00-11), p.254 - 257, 2000/11
no abstracts in English
Yasuda, Kenichiro; Usuda, Shigekazu; Gunji, Hideho
IEEE Transactions on Nuclear Science, 47(4), p.1337 - 1340, 2000/08
Times Cited Count:8 Percentile:50.62(Engineering, Electrical & Electronic)no abstracts in English
Sakasai, Kaoru; H.Bueker*; F.W.Haesing*; F.Pfeiffer*
JAERI-Research 99-038, 18 Pages, 1999/05
no abstracts in English
JAERI-Conf 98-011, 84 Pages, 1998/07
no abstracts in English