Turbine generator in power plants is an important equipment, and requires its preventive maintenance for normal operation.For the inspection efficiency for turbine generator rotor, the application of ultrasonic testing technique for the keyway in a rotor shaft is demanded. The ultrasonic testing for the keyway in a rotor shaft detects crackings occurred diagonally for rotor axis. For this issue, the authors developed the cracking detection techniques by the phased array ultrasonic testing method using an array probe installed in the distant position from the keyway. The ultrasonic beams propagate three-dimensionally because the rotor shaft is a column. Therefore a control of the beam incident direction is difficult. Therefore the ultrasonic beam angle and the ultrasonic probe position for cracking detection were calculated based on the rotor's geometry. The authors confirmed the possibility of crackings detection in this calculated condition by the experiment using electric discharge machining slit in the specimen simulated a rotor shaft, and ensured the inspection reliability.

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J-STAGEにおいて2022年11月14日に早期公開された下記の原著論文（doi: 10.20619/jcombsj.2203）について引用文献に誤りがありましたので，著者からの申し出により，下記のとおり訂正します．

References
【誤】2. E.S. Sanz-Perez et al., “Direct Capture of CO2 from Ambient Air”, Chem. Rev. 116, 11840-11876, 2016. Bianco, Y., Cheng, W.K., and Heywood, J.B., Combust Flame 110: 1646-1652 (1990).
【正】2. E.S. Sanz-Perez et al., “Direct Capture of CO2 from Ambient Air”, Chem. Rev. 116, 11840-11876, 2016.

※本誌，日本燃焼学会誌210号には本論文の訂正版を掲載しています．

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The system detecting crack on tunnel wall selectively by vehicle passing in tunnel has been proposed. That system consists of mechanoluminescence and TDI camera. In this paper, we report about the quantification of mechanoluminescence of crack due to pressure change, and the applicability of TDI camera to detecting mechanoluminescence of crack. Firstly, selective mechanoluminescence on crack due to pressure change is demonstrated. Experimental setup includes cylinder piston compressing enclosed space and test plate with simulated crack placed at bottom face of enclosed space. The surface of test plate with simulated crack is coated by mechanoluminescence particles. When a pressure change of 3.5 kPa occurs in enclosed space, the surface of test plate produces luminescence along the crack shape and luminescence value is 6 gray digits by CCD camera. Thus, mechanoluminescence of crack shape by pressure change is demonstrated. Secondly, detection of weak luminescence during moving is demonstrated. Experimental setup includes the rotating circular plate with luminous target on outer side. When the outer circumference rotates in 300 km/h, the target that luminescence value sets 6 gray digits corresponded by CCD camera is not detected by TDI camera. When the luminescence value is set to 300 times of 6 gray digits, it is detected by TDI camera. Thus, detection of mechanoluminescence of crack in 300 km/h movement by TDI camera is possible, if the strength of mechanoluminescence or sensitivity of TDI camera is enhanced by 300 times.

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SID '99のLCD Technologyに関するOral Session(S5:Fast LCDs, S10:Wide-VIewing-Angle LCDs, S16:LC Modeling/Wide Viewing Angle, S33:LC Microdisplays, S45:Reflective LCDs、合計17件)及びPoster Session(Wide-VIewing-Angle LCDs, Reflective LCDs, LC Modelingの13件)の中から注目すべき発表について報告する。

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ダイヤモンドのマイクロポーラ材料として弾性定数をその音との分散に関する実験データから推算する. まず, 立方異方性マイクロポーラ弾性体の分散曲線を求める. 六つの基本波が存在する. ダイヤモンドの物性定数はこのうちの三つの波動の分散曲線が実験データに適合するよう決定される. 局所(または微視)慣性モーメントも, 物性定数の一つとして与えられる.

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AI制御システムを産業プラントに適用する際，制御方法の学習に必要な運転データが不足すると，制御性能が低下する課題がある．本論文では事前に収集した運転データを用いた通常の学習で所望の制御性能が得られなかった場合に，シミュレータを活用して追加学習用のデータを生成する手法を提案する．本手法ではまず，目標状態に到達した時に得られる報酬を定義し，報酬の得られる期待値である状態価値を求める．次に，近傍の状態から状態価値の標準偏差を求め，標準偏差の大きい領域を学習データが不足している領域とする．そして，この領域で乱数を用いて試行錯誤的な制御設定値を用いた操作を実施することで不足データを収集する．最後に，収集したデータを用いた追加学習により，制御性能を向上させる．提案手法の効果を酢酸ビニルモノマー製造プラントのシミュレータを用いて検証した．エチレン供給圧力の異常が発生した時の気化器圧力復旧操作を学習した結果，学習データ不足時に発生するオーバーシュートを追加学習によって抑制し，整定時間を67 minから37 minに改善できることを確認した．

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The 21st International Display Research Conference in conjunction with The 8th International Display Workshops(Asia Display/IDW '01)における Work shop on LC Science and Technologiesの主な発表について報告する。

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It is predicted that the demand for electric equipment that can achieve high efficiency and energy savings will continue to increase However, there are concerns about resource depletion of materials for high-performance magnets, which are essential for highly efficient electric equipment. We considered reducing the amount of rare metals by increasing the coercive force through grain boundary diffusion of heavy rare earth materials and by separating the magnets of linear motors. The results showed the possibility of significantly reducing the usage of rare materials such as Dy and Tb. Furthermore,in order to evaluate the basic performance of the electromagnetic suspension, a prototype linear motor using divided permanent magnets was fabricated and its thrust characteristics were evaluated. As a result, it was confirmed that the expected thrust characteristics could be obtained.

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