強化学習など機械学習を用いたプラズマ制御手法の開発
キーワード：機械学習、強化学習、ニューラルネットワーク
2022.04～2028.03.

トカマクプラズマの定常運転に向けた統合制御手法の開発
キーワード：統合制御、トカマク、定常運転、大容量データベース
2010.04.

定常運転球状トカマクにおけるプラズマ形状のリアルタイム同定とその制御
キーワード：プラズマ形状、リアルタイム、制御、定常運転
2011.04.

大規模プラズマ実験における効果的な統合的実験システムの開発
キーワード：遠隔実験参加、データ収集、監視制御システム、大規模プラズマ実験、IoT (Internet of Things)
2003.10.

高周波ならびに誘導電場による初期プラズマ生成に関する研究
キーワード：Townsend avalanche, プラズマ, マイクロ波, ブレークダウン
2000.07.

QUEST計画
2005.04, 代表者：花田和明, 九州大学 応用力学研究所, 核融合科学研究所（日本）
プラズマ境界力学実験(QUEST)装置を用いた核融合炉開発研究の基礎実験研究.

QUEST装置を用いたSNETベースの遠隔・定常データ収集法の開発
2008.04, 代表者：中西 秀哉, 核融合科学研究所・大型ヘリカル研究部, 核融合科学研究所（日本）
九州大学応力研とNIFSとの双方向型共同研究では，将来のSTプラズマ実験とその定常化に向けた研究が進められているが，高速インターネット基盤SNETの利用による全日本ST実験体制の整備と技術開発もその課題の一つである．本研究では，LHDで開発された高速・定常データ収集システム技術を更に拡張して，応力研サイト・LHDサイトの両方にまたがる計測データ収集系の仮想連携システムを開発・検証すると共に，複数サイト間でのデータ収集リソースのオンライン共有など，より効率的な核融合実験の将来像を探る．
本研究は、２００７年度よりCPD装置にて行われていた遠隔・定常データ収集に関する研究が更に発展し、QUEST装置の本格稼動に伴い、更に諸課題を解決するために継続している。.

主要原著論文

1.	Makoto HASEGAWA, Aki HIGASHIJIMA, Ichiro NIIYA, Kazuaki HANADA, Hiroshi IDEI, Takeshi IDO, Ryuya IKEZOE, Takumi ONCHI, Kengo KURODA and Daisuke SAKURAI, QUEST Database for Tokamak Big Data, Plasma and Fusion Research, 10.1585/pfr.18.1305048, 18, 1305048-1-1305048-4, 2023.05, A database has been developed to provide a highly efficient data analysis environment by registering various types of data obtained in the QUEST (Q-shu University Experiment with Steady-State Spherical Tokamak) experiments and providing the data to researchers through standard SQL query output. In conventional experiments, measurements are usually obtained using several instruments, and the results are often stored separately in proprietary formats. An analysis to collect distributed files and convert them into appropriate formats individually was necessary, which led to a decrease in analysis efficiency. In order to build a system to centrally store and provide data, we constructed new servers, each for registering data in a database and for extracting data from the database and visualizing the data. As a result, various real-time monitoring data can be registered in the database, and data retrieval for analysis can be performed easily with a unified user interface. The construction of this database has made it possible to easily retrieve real-time monitoring data and a wide variety of table data, enabling analysis from a new perspective, and improving analysis efficiency..
2.	Makoto Hasegawa, Daisuke Sakurai, Aki Higashijima, Ichiro Niiya, Keiji Matsushima, Kazuaki Hanada, Hiroshi Idei, Takeshi Ido, Ryuya Ikezoe, Takumi Onchi, Kengo Kuroda, Towards automated gas leak detection through cluster analysis of mass spectrometer data, Fusion Engineering and Design, https://doi.org/10.1016/j.fusengdes.2022.113199, 180, 113199, 2022.06, In order to generate high-performance plasma for future fusion power generation, it is desirable to keep high quality vacuum during experiment. Mass spectrometer is commonly used to monitor the vacuum quality and to record the amount of atoms and molecules in the vacuum vessel. Leak is the most serious accident to avoid that can nullify an experiment and even harm researchers. Detecting leaks are ever more important since it can be easily overlooked, e.g., when the deterioration in the vacuum degree is modest. This forces the researcher to carefully observe the vacuum and mass spectrometer data. This article presents a way to suggest potential leaks in the vacuum vessel by analyzing mass spectrometer data. This is done by utilizing the Euclidean distance between composition ratios at different times for the clustering using the daily composition ratio. We show that our cluster analysis is an effective way of separating these two cases, which results in a semi-automatic determination of leaks is more efficient than the current norm, which is to check many measures to find a small abnormality in the data manually. We plan further model improvements for long-term evaluation..
3.	Makoto HASEGAWA, Kazuaki HANADA, Naoaki YOSHIDA, Hiroshi IDEI, Takeshi IDO, Yoshihiko NAGASHIMA, Ryuya IKEZOE, Takumi ONCHI, Kengoh KURODA, Shoji KAWASAKI, Aki HIGASHIJIMA, Takahiro NAGATA, Shun SHIMABUKURO and Kazuo NAKAMURA, Extension of Operation Region for Steady State Operation on QUEST by Integrated Control with Hot Walls, Plasma and Fusion Research, 10.1585/pfr.16.2402034, 16, 2402034, 2402034-1-2402034-8, 2021.01, [URL], The controllability of particle supply during long-term discharge in a high-temperature environment was investigated at the Q-shu University Experiment with steady state spherical tokamak (QUEST). QUEST has a high-temperature wall capable of active heating and cooling as a plasma-facing wall. With this hot wall, a temperature rise test was conducted with 673K as the target temperature. It was confirmed that the hot wall could maintain the temperature above 600 K. Feedback control of particle fueling was conducted to control Hα emission, which is closely related to influx to the wall. Using this particle fueling control and setting the hot wall temperature to 473 K, it was possible to obtain a discharge of more than 6 h. In this discharge, the fueling rate of particles decreased with time, and finally became zero, losing the particle fueling controllability. However, as soon as the cooling water started to flow through the hot wall, particles could be supplied again, and controllability was restored. Thus, indicating that temperature control of the plasma first wall is important even in the high temperature environment of 473K to control particle retention of the wall..
4.	Makoto Hasegawa, Kazuaki Hanada, Hiroshi Idei, Shoji Kawasaki, Takahiro Nagata, Ryuya Ikezoe, Takumi Onchi, Kengoh Kuroda, Aki Higashijima, Predictive maintenance and safety operation by device integration on the QUEST large experimental device, Heliyon, https://doi.org/10.1016/j.heliyon.2020.e04214, 6, e04214, accepted, 2020.06, As technology has improved in recent years, it has become possible to create new valuable functions by combining various devices and sensors in a network. This concept is referred to as the Internet of Things (IoT), and predictive maintenance is a new valuable function associated with the IoT. In large-scale experimental facilities with many researchers, it is not desirable that experiments cannot be performed due to sudden failure of equipment. For this reason, it is important to predict the failure in advance based on the measurement results of sensors and to perform repairs in a planned manner. On the Q-shu University experiment with steady-state spherical tokamak (QUEST) large experimental device, it is necessary to drive a large current of 50 kA, and the diagnosis of its power line deterioration is well performed as predictive maintenance through the evaluation of its contact resistances of several micro ohms order on the network. In addition, as an example of the IoT, mechanisms to assist safe operation, such as a sound alarm system and an entrance management system, are built by sharing experimental information between devices via the network..
5.	Makoto Hasegawa, Kazuo Nakamura, Kazuaki Hanada, Shoji Kawasaki, Arseniy Kuzmin, Hiroshi Idei, Kazutoshi Tokunaga, Yoshihiko Nagashima, Takumi Onchi, Kengoh Kuroda, Osamu Watanabe, Aki Higashijima, Takahiro Nagata, Modification of plasma control system and hot-wall temperature control system for long-duration plasma sustainment in QUEST, Fusion Engineering and Design, 10.1016/j.fusengdes.2018.02.069, 129, 202-206, 2018.04, [URL], In tokamaks, the temperature of the plasma-facing wall is an important parameter for achieving particle balanceand therefore steady-state operation. QUEST, which is a middle-sized spherical tokamak, has hot walls that act asplasma-facing walls. They can be actively heated with sheath heaters and actively cooled with water. To controlthe wall temperature, heating and cooling systems have been developed. These systems adjust the power of thesheath heaters and the motor valves of the cooling system, respectively. The two systems communicate viaEthernet through UDP and control the hot-wall temperature cooperatively. The plasma control system (PCS) inQUEST has also been modified, especially with respect to gas fueling, in order to enable long-duration plasmasustainment. A feedback controller has been installed in the PCS, together with a mass flow controller, allowingHα emission from the plasma which is used as a reference signal, to be well controlled. Plasma density calculationsusing a field-programmable gate array are proposed for the feedback control system..
6.	長谷川 真, 中村 一男, 花田 和明, 藤澤 彰英, 出射 浩, 徳永 和俊, 永島 芳彦, 恩地 拓己, 東島 亜紀, 永田 貴大, 川崎 昌二, 渡邉 理, 黒田 賢剛 , QUESTにおける制御システムの現状紹介と展望, 九州大学応用力学研究所所報, 153, 75-79, 2017.09, QUEST is a middle-sized spherical tokamak, which has a capability of long term plasma discharge. Thus, the QUEST is suitable for the study of steady state operation such as energy and particle balances and particle recycling. For the sustainment of steady-state plasma, it may be required such as high performance control systems, various sensors and actuators, technics for real-time calculation methods, and so on. In this paper, the present status of control systems on QUEST are presented, and its perspectives are also described. The central control system will be improved with easy comprehensible user interface and Ethernet environment. And, the plasma control system identify the plasma position and its current with hall sensors in real-time continuously without drift errors. The plasma on QUEST will be controlled integrally with the cooperation of these systems. .
7.	Makoto Hasegawa, Kazuo Nakamura, Hideki Zushi, K.Hanada, Fujisawa Akihide, K. Tokunaga, Hiroshi Idei, Nagashima Yoshihiko, Shoji Kawasaki, Hisatoshi Nakashima, Aki Higashijima, Current status and prospect of plasma control system for steady-stateoperation on QUEST, Fusion Engineering and Design, http://dx.doi.org/10.1016/j.fusengdes.2016.04.016, 112, 699-702, Vol. 112, pp. 699-702, 2016.12, The plasma control system (PCS) of QUEST is developed according to the progress of QUEST project. Sinceone of the critical goals of the project is to achieve the steady-state operation with high temperaturevacuum vessel wall, the PCS is also required to have the capability to control the plasma for a long period.For the increase of the loads to processing power of the PCS, the PCS is decentralized with the use ofreflective memories (RFMs). The PCS controls the plasma edge position with the real-time identificationof plasma current and its position. This identification is done with not only flux loops but also hall sensors.The gas fueling method by piezo valve with monitoring the H signal filtered by a digital low-pass filterare proposed and suitable for the steady-state operation on QUEST. The present status and prospect ofthe PCS are presented with recent topics..
8.	長谷川 真, 中村 一男, 図子 秀樹, 花田 和明, Akihide Fujisawa, H.Idei, 德永 和俊, 永島 芳彦, 東島 亜紀, 川崎 昌二, 中島 寿年, KUZMIN ARSENIY ALEKSANDROVICH, 恩地 拓己, 渡辺 理, Mishra Kishore Kanti, QUESTにおける長時間放電でのホール素子を用いたプラズマ電流と位置のリアルタイム同定, 九州大学応用力学研究所所報, 149, 10-15, 2015.09, プラズマを高温・高密度で真空容器内に閉じ込めるトカマク装置において、真空容器外に設置したホール素子を用いて、真空容器内のプラズマ電流およびプラズマ位置を評価する方法の提案をおこない、その結果を球状トカマク装置QUESTに適用して、他の磁気計測による方法と比較して適切に評価が行えることを確認した。.
9.	Makoto Hasegawa, Kazuo Nakamura, hideki zushi, kazuaki hanada, Akihide Fujisawa, Osamu Mitarai, KAZUTOSHI TOKUNAGA, Hiroshi Idei, Yoshihiko Nagashima, Shoji Kawasaki, Hisatoshi Nakashima, Aki Higashijima, Development of a high-performance control system bydecentralization with reflective memory on QUEST, Fusion Engineering and Design, 96-97, 629-632, 96-97 (2015) 629-632, 2015.07, The plasma control system (PCS) of QUEST was a centralized system, which lost its scalability because ofthe overload imposed on its central processing unit (CPU) of the PCS, making it impossible to add newfunctions. Thus, the PCS is distributed into a main workstation (WS) and subsystem (SS) with a reflectivememory (RFM) in order to share data between these systems so as to mitigate the load on each system.As a result, 128 double-precision floating-point numbers (DBLs) can be transferred from the SS to the WSwith a maximum latency of 250 s. The WS and the SS each have quad-core CPUs, and tasks are executedin parallel. Although one of the four cores is intermittently occupied by up to 90% by this transaction, theoccupation is normally 60%. A time correction procedure is used to map the recorded data sets on theWS and the SS to a common time base by referring to the time difference between two systems..
10.	Makoto Hasegawa, Kazuo Nakamura, hideki zushi, kazuaki hanada, Akihide Fujisawa, Keisuke Matsuoka, Hiroshi Idei, Yoshihiko Nagashima, KAZUTOSHI TOKUNAGA, Shoji Kawasaki, Hisatoshi Nakashima, Aki Higashijima, Development of a plasma control system for steady-state operation on QUEST, JOURNAL OF THE KOREAN PHYSICAL SOCIETY, 10.3938/jkps.65.1191, 65, 8, 1191-1195, 2014.10, A drift error correction technique with machine vision and a real-time equilibrium calculation code have been developed on the QUEST (Q-shu university experiment with the steady-state spherical tokamak) for steady-state operation. The drift error caused by the long time-integration of magnetic raw signals has to be removed. With a captured image of the plasma’s cross section, the plasma’s position is identified by use of image filters. The measured magnetic flux values are corrected to the calculated flux values estimated by using this plasma position. The correction with the captured image work as expected in the preliminary result using a flashlight instead of a plasma..
11.	Hasegawa, M.; Nakamura, K.; Zushi, H.; Hanada, K.; Fujisawa, A.; Matsuoka, K.; Mitarai, O.; Idei, H.; Nagashima, Y.; Tokunaga, K.; Kawasaki, S.; Nakashima, H.; Higashijima, A., Development of plasma control system for divertor configuration on QUEST, FUSION ENGINEERING AND DESIGN, 10.1016/j.fusengdes.2013.03.035, 88.0, 6.0, 1074.0-1077.0, 0.0, 2013.10, A plasma control system to sustain divertor configurations is developed on QUEST (Q-shu university experiment with steady-state spherical tokamak). Magnetic fluxes are numerically integrated at 100 kHz using FPGA (Field-Programmable Gate Array) modules and transferred to a main calculation loop at 4 kHz. With these signals, plasma shapes are identified in real time at 2 kHz under the assumption that the plasma current can be represented as one filament current. This calculation is done in another calculation loop in parallel by taking advantage of a multi-core processor of the plasma control system. The inside and outside plasma edge positions are controlled to their target positions using PID (proportional-integral-derivative) control loops. Whereas the outside edge position can not be controlled by the outer PF coil current, the inside edge position can be controlled by the inner PF coil current. (C) 2013 Elsevier B.V. All rights reserved..
12.	Makoto Hasegawa, Kazuo Nakamura, Kazutoshi Tokunaga, Hideki Zushi, Kazuaki Hanada, Akihide Fujisawa, Hiroshi Idei, Shoji Kawasaki, Hisatoshi Nakashima, Aki Higashijima, A Plasma Shape Identification with Magnetic Analysis for the Real-time Control on QUEST, IEEJ Transactions on Fundamentals and Materials, 10.1541/ieejfms.132.477, 132.0, 7.0, 477.0-484.0, 2012.07, In order to identify plasma shape, there is a way to represent the plasma current profile with several parameters, and adjust these parameters with least-square technique in order for calculated magnetic values to accord with measured ones. Here, the plasma shape parameters such as minor radius, elongation, and triangularity are chosen as the fitting parameters to represent plasma shape more directly, and the applicability to the control of the plasma shape are described by evaluating its calculation time. In order to find minimum of an objective function with least-square technique, two methods are compared, namely a linear approximation method and a downhill simplex method. While high accuracies of the measured magnetic signals are required, the good reproducibility is obtained, and the plasma shape identification can be done within several milliseconds in both methods..
13.	Hasegawa, M.; Higashijima, A.; Nakamura, K.; Hanada, K.; Sato, K. N.; Sakamoto, M.; Idei, H.; Kawasaki, S.; Nakashima, H., A WEB-based integrated data processing system for the TRIAM-1M, FUSION ENGINEERING AND DESIGN, 10.1016/j.fusengdes.2007.12.012, 83.0, 4.0, 588.0-593.0, 2008.05, In TRIAM-1M, plasma discharge can be sustained for over five hours [H. Zushi, et al., Steady-state tokamak operation, ITB transition and sustainment and ECCD experiments in TRIAM-1M, Nucl. Fusion 45 (2005) S142-S156]. In order to avoid sitting in front of one console for the purpose of monitoring the plasma discharge, it is recommended that the experimental information be accessible from any location at any time. In addition, simple services to access experimental information are required in order to promote the participation of multiple researchers in the TRIAM-1M experiment. Thus, A WEB-based integrated data processing system that provides management for experiment planning, an experimental log, numerical data, and plasma supervision has been installed in the TRIAM-1M. These services are composed primarily of an Apache WEB server, a Tomcat JSP/Servlet container, and a MySQL relational database. This system is constructed using the object-oriented Java language, which is easy to maintain and develop because of the intrinsic characteristics of the Java language. When participating in experiments, researchers are required only to prepare a WEB browser on any platform and are no longer required to memorize complex operations because all services are provided with a uniform user interface through a WEB browser. Furthermore, with the integration of these services, the required information and numerical data can be provided promptly by tracing HTML links that are created dynamically by server applications. (C) 2007 Elsevier B.V. All rights reserved..
14.	Hasegawa, M.; Nakamura, K.; Higashijima, A.; Kawasaki, S.; Nakashima, H.; Sato, K. N.; Zushi, H.; Hanada, K.; Sakamoto, A.; Idei, H., High accessible experimental information on CPD experiment, FUSION ENGINEERING AND DESIGN, 10.1016/j.fusengdes.2007.10.014, 83.0, 2.0, 402.0-405.0, 2008.04, On CPD [1] (Compact PWI experimental Device) experiment, information of electronic logbook and sequence status are distributed by Web services to prepare future experimental environment such as steady state operation and remote participation. Hence, all the researchers can acquire information with a Web browser installed on a personal computer if they are connected to the Internet. However, to carry a notebook computer all the time is a burden to researchers. Furthermore, the researchers may not be always connected to the Internet. Mobile phones are superior in portability compared to notebook computers, and are easy to connect with Internet through the wireless network of the telecom carriers. Moreover, since recent mobile phones have full browsing function, their affinities to the Web services are becoming high. On this account, Web services for mobile phones are developed to access experimental information. For sequence monitoring, a mobile application MIDlet that utilizes special functions of mobile phone such as sound and vibration is also developed to draw attentions of researchers to sequence status. (C) 2007 Elsevier B.V. All rights reserved..
15.	Hasegawa, Makoto; Hanada, Kazuaki; Sato, Kohnosuke; Nakamura, Kazuo; Zushi, Hideki; Sakamoto, Mizuki; Idei, Hiroshi; Kawasaki, Shoji; Nakashima, Hisatoshi; Higashijima, Aki, Initial plasma production by Townsend avalanche breakdown on QUEST tokamak, JAPANESE JOURNAL OF APPLIED PHYSICS, 10.1143/JJAP.47.287, 47.0, 1.0, 287.0-292.0, 2008.01, On tokamak devices, an induction electric field induced by poloidal field (PF) coils plays a role to produce initial plasma. On a DIII-D tokamak, the required induction electric field for plasma breakdown agrees well with theoretical predictions based on the Townsend avalanche theory. According to the Townsend avalanche theory, the minimum induction electric field for plasma breakdown depends on neutral gas pressure and connection length. For stable plasma breakdown, a sufficiently large induction electric field is required. However, in the case of spherical tokamaks without electric insulation in the toroidal direction, the effect of eddy currents flowing in the toroidal direction should be considered in evaluating a feasible induction electric field because this effect suppresses the generation of an induction electric field. On a QUEST spherical tokamak, the possibility of Townsend avalanche breakdown is studied by evaluating the connection length and achievable induction electric field. The connection length is greater than 100 in in the case where a null point is set to be R = 0.56 in with a CS coil current of 2.0 kA and a PF26 coil current of 0.4 kA. Moreover, the induction electric field is about 1.5 V at this point including the effect of eddy currents. With these values, the initial plasma production by the induction electric field is sufficiently possible on QUEST..
16.	Hasegawa, Makoto; Hanada, Kazuaki; Sato, Kohnosuke; Nakamura, Kazuo; Zushi, Hideki; Sakamoto, Mizuki; Idei, Hiroshi; Kawasaki, Shoji; Nakashima, Hisatoshi; Higashijima, Aki, Model of inductive plasma production assisted by radio-frequency wave in tokamaks, JOURNAL OF NUCLEAR MATERIALS, 10.1143/JPSJ.76.084501, 76.0, 8.0, 0.0-0.0, 084501, 2007.08, For initial plasma production, an induction electric field generated by applying voltage to a poloidal field (PF) coil system is used to produce a Townsend avalanche breakdown. When the avalanche margins are small, as for the International Thermonuclear Experimental Reactor (ITER) in which the induction electric field is about 0.3 V/m, the assistance of radio-frequency waves (RF) is provided to reduce the induction electric field required for reliable breakdown. However, the conditions of RF-assisted breakdown are not clear. Here, the effects of both RF and induction electric field on the RF-assisted breakdown are evaluated considering the electron loss. When traveling loss is the dominant loss, a simple model of an extended Townsend avalanche is proposed. In this model, the induction electric field required for RF-assisted breakdown can be decreased to half that required for induction breakdown..
17.	M. Hasegawa, K. Nakamura, K. N. Sato, K. Hanada, H. Zushi, M. Sakamoto, H. I dei, S. Kawasaki, H. Nakashima, A. Higashijima, QUEST装置における誘導電場による初期プラズマ生成, 九州大学大学院総合理工学報告, 第28巻第4号，pp. 391-398, 2007.04.
18.	Makoto HASEGAWA, Kazuaki HANADA, Kohnosuke SATO, Kazuo NAKAMURA, Hideki ZUSHI, Mizuki SAKAMOTO, Hiroshi IDEI, Shoji KAWASAKI, Hisatoshi NAKASHIMA and Aki HIGASHIJIMA , Townsend Avalanche Breakdown Assisted by Radio Frequency Wave in Tokamaks, Plasma and Fusion Research, 2.0, RC, Article No. 007, 2007.03.
19.	Nakamura, K; Ji, ZS; Shen, B; Qin, PJ; Itoh, S; Hanada, K; Sakamoto, M; Jotaki, E; Hasegawa, M; Iyomasa, A; Kawasaki, S; Nakashima, H, Magnetic sensorless sensing of plasma position in the superconducting tokamak HT-7, PLASMA SCIENCE & TECHNOLOGY, 10.1088/1009-0630/6/5/006, 6.0, 5.0, 2459.0-2462.0, 0.0, 2004.10, Magnetic sensorless sensing experiments of the plasma horizontal position have been carried out in the superconducting tokamak HT-7. The horizontal position is calculated from the vertical field coil current and voltage without using signals of magnetic probes placed nearby a plasma. The calculations are focused on the ripple frequency component of the power supply. There is no drift problem with the time integration of magnetic probe signals. The error of the derived plasma position is lower than 2% of the plasma minor radius..
20.	M. Hasegawa, K. Hanada, S. Itoh, K. Nakamura, H. Zushi, M. Sakamoto, E. Jotaki, S. V. Kulkarni, A. Iyomasa, S. Kawasaki, H. Nakashima, K. Nagasaki, Plasma Experiments Using a New 170GHz EC System and a Simple Model for Plasma Production, JOURNAL OF NUCLEAR MATERIALS, Vol.80, No.1 pp.53-58, 2004.01.
21.	Nakamura, K; Ji, ZS; Shun, B; Qin, PQ; Itoh, S; Hanada, K; Sakamoto, M; Jotaki, E; Hasegawa, M; Iyomasa, A; Kawasaki, S; Nakashima, H, Sensorless sensing of plasma horizontal position on HT-7, FUSION ENGINEERING AND DESIGN, 10.1016/S0920-3796(03)00308-9, #<:excel::error:0xacee67c>, 0.0, 771.0-777.0, 0.0, 2003.09, Sensorless sensing experiments of the plasma horizontal position have been carried out in the superconducting tokamak HT-7. The horizontal position is calculated from the vertical field coil current and voltage in two ways. The calculations are made focusing on the low frequency component and the ripple frequency component of the power supply. In the latter case, there is no drift problem and the error is lower than 2% of the plasma minor radius. (C) 2003 Elsevier Science B.V. All rights reserved..

主要総説, 論評, 解説, 書評, 報告書等

主要学会発表等

1.	長谷川 真，井戸 毅，花田 和明, 出射 浩, 池添 竜也, 恩地 拓己, 木下 稔基, トカマクプラズマ位置形状の機械学習を用いた高速同定, 令和６年電気学会全国大会, 2024.03, [URL].
2.	長谷川 真, QUEST Group, クエストのプラズマ制御システムと機械学習によるプラズマ形状の高速同定, 第１９回クエスト研究会, 2024.03, [URL].
3.	Makoto Hasegawa, and QUEST Group, Plasma control system of QUEST and fast plasma shape recognition with Machine Learning, 12th QUEST Workshotp "RF startup and sustainment in Spherical Tokamak", 2024.02, [URL].
4.	長谷川 真, and QUESTグループ, QUESTの長時間運転における計測と制御, 第25回若手科学者によるプラズマ研究会, 2023.03, [URL].
5.	長谷川 真, and QUESTグループ, 共同利用装置QUESTの実験環境および実験データについて, 第１８回クエスト研究会, 2022.09, [URL].
6.	長谷川 真, QUESTグループ, 実験装置の概要(II) QUEST , 先進トカマク研究会, 2022.09.
7.	Makoto Hasegawa, Introduction of large plasma experimental device QUEST, Sakura Science for HFUT, 2021.11.
8.	Makoto Hasegawa, Long-time operation with high temperature wall (
9.	長谷川 真, QUESTにおける高温壁(
10.	M. Hasegawa, K. Hanada, N. Yoshida, H. Idei, T. Ido, Y. Nagashima, R. Ikezoe, T. Onchi, K. Kuroda, S. Kawasaki, A. Higashijima, T. Nagata, S. Shimabukuro, K. Nakamura, QUESTにおける高温壁(
11.	Makoto Hasegawa, Daisuke Sakurai, Aki Higashijima, Ichiro Niiya, Keiji Matsushima, Kazuaki Hanada, Hiroshi Idei, Takeshi Ido, Ryuya Ikezoe, Takumi Onchi, Kengo Kuroda, Towards Automated Gas Leak Detection through Cluster Analysis of Mass Spectrometer Data, 13th Technical Meeting on Plasma Control Systems, Data Management and Remote Experiments in Fusion Research, 2021.07, In order to generate high-performance plasma for future fusion power generation, it is desirable to keep high quality vacuum during experiment. Mass spectrometer is commonly used to monitor the vacuum quality and to record the amount of atoms and molecules in the vacuum vessel. Leak is the most serious accident to avoid that can nullify an experiment and even harm researchers. Detecting leaks are ever more important since it can be easily overlooked, e.g., when the deterioration in the vacuum degree is modest. This forces the researcher to carefully observe the vacuum and mass spectrometer data. This article presents a way to suggest potential leaks in the vacuum vessel by analyzing mass spectrometer data. This is done by utilizing the Euclidean distance between composition ratios at different times for the clustering using the daily composition ratio. We show that our cluster analysis is an effective way of separating these two cases, which results in a semi-automatic determination of leaks is more efficient than the current norm, which is to check many measures to find a small abnormality in the data manually. We plan further model improvements for long-term evaluation..
12.	M. Hasegawa, K. Hanada, N. Yoshida, H. Idei, T. Ido, Y. Nagashima, R. Ikezoe, T. Onchi, K. Kuroda, S. Kawasaki, A. Higashi, T. Nagata, S. Shimabukuro, K. Nakamura, Extension of Operation Area for Steady State Operation on QUEST by Integrated Control with Hot Walls, 9th International Workshop, RIAM 2021, 2021.01, [URL], Steady state operation of magnetically confined plasmas has been studied on the Q-shu University Experiment with steady state spherical tokamak (QUEST). In future power plants, to increase power generation efficiency by heat exchange, its operation temperature will be around 773 K, and it is desirable to realize steady state operation. However, the uncontrollable increase in plasma density, which tends to occur with high temperature walls, prevents the realization of them. They are definitely relating to plasma-wall interaction (PWI) and particle balance, and more detailed studies are required. QUEST has all-metal plasma facing walls (PFWs) and its temperature can be controlled with resistive heaters and cooling water. The typical operating temperature range on the PFWs is between room temperature and less than 773 K. To control the temperature on the PFWs, hot walls and radiation shields have been installed inside the vacuum vessel on QUEST. The radiation shields prevent the outflow of heat so that the hot wall, namely PFW, can be maintained at high temperatures. Recently, tokamak plasma discharges longer than 6 h were achieved with full non-inductive electron cyclotron current drive (ECCD) using a RF source of 8.2 GHz. The input RF power was in the range of 20 kW, and the wall temperature was higher than 423 K. In these shots, particle fueling were properly feedback-controlled to keep plasma influx constant by referring Ha emission. However, in typical long discharge, the fueling gradually decreased and finally stopped due to a so-called “wall saturation”. This indicates the unknown particle sources is significantly affecting in the particle balance. On the other hand, when the cooling water for the hot walls was circulated under these situations, the particle fueling was observed to restart spontaneously. This also indicates that the integrated control including particle fueling and temperature of PFWs is important and this realization contributes expansion of operation area toward steady state operations..
13.	M. Hasegawa, K. Hanada, N. Yoshida, H. Idei, T. Ido, Y. Nagashima, R. Ikezoe, T. Onchi, K. Kuroda, S. Kawasaki, A. Higashi, T. Nagata, S. Shimabukuro, K. Nakamura, Extension of Operation Area for Steady State Operation on QUEST by Integrated Control with Hot Walls, The 29th International Toki Conference on Plasma and Fusion Research (ITC29), 2021.01, [URL], Steady state operation of magnetically confined plasmas has been studied on the Q-shu University Experiment with steady state spherical tokamak (QUEST). In future power plants, to increase power generation efficiency by heat exchange, its operation temperature will be around 773 K, and it is desirable to realize steady state operation. However, the uncontrollable increase in plasma density, which tends to occur with high temperature walls, prevents the realization of them. They are definitely relating to plasma-wall interaction (PWI) and particle balance, and more detailed studies are required. QUEST has all-metal plasma facing walls (PFWs) and its temperature can be controlled with resistive heaters and cooling water. The typical operating temperature range on the PFWs is between room temperature and less than 773 K. To control the temperature on the PFWs, hot walls and radiation shields have been installed inside the vacuum vessel on QUEST. The radiation shields prevent the outflow of heat so that the hot wall, namely PFW, can be maintained at high temperatures. Recently, tokamak plasma discharges longer than 6 h were achieved with full non-inductive electron cyclotron current drive (ECCD) using a RF source of 8.2 GHz. The input RF power was in the range of 20 kW, and the wall temperature was higher than 423 K. In these shots, particle fueling were properly feedback-controlled to keep plasma influx constant by referring Ha emission. However, in typical long discharge, the fueling gradually decreased and finally stopped due to a so-called “wall saturation”. This indicates the unknown particle sources is significantly affecting in the particle balance. On the other hand, when the cooling water for the hot walls was circulated under these situations, the particle fueling was observed to restart spontaneously. This also indicates that the integrated control including particle fueling and temperature of PFWs is important and this realization contributes expansion of operation area toward steady state operations..
14.	長谷川真、QUESTグループ, QUESTで実装している幾つかの制御手法とそのシステム, 平衡再構成のための計測技術と解析手法, 2018.07.
15.	Makoto Hasegawa, Introduction of experimental system on large plasma experimental device QUEST, さくらサイエンスプラン, 2017.12, ●Introduction of QUEST 　・History of long duration discharges ●Exp. system including plasma control system on QUEST ●Usage of FPGA as software-defined technology ●Information sharing with Ethernet for coordinated operation ●Summary.
16.	M. Hasegawa, K. Hanada, N. Yoshida, A. Kuzmin, H. Zushi, K. Nakamura, A. Fujisawa, H. Idei, Y. Nagashima, O. Watanabe, T. Onchi, K. Kuroda, H. Watanabe, K. Tokunaga, A. Higashijima, S. Kawasaki, and T. Nagata, Efforts toward Steady State Operation in Long Duration Discharges　with the Control of Hot Wall Temperature on QUEST, 1st Asia-Pacific Conference on Plasma Physics, 2017.09, Efforts toward Steady State Operation in Long Duration Discharges with the Control of Hot Wall Temperature on QUEST M. Hasegawa1, K. Hanada1, N. Yoshida1, A. Kuzmin1, H. Zushi1, K. Nakamura1, A. Fujisawa1, H. Idei1, Y. Nagashima1, O. Watanabe1, T. Onchi1, H. Watanabe1, K. Tokunaga1, A. Higashijima1, S. Kawasaki1, and T. Nagata1 1 RIAM, Kyushu University, Japan Achievement of steady state operation (SSO) of magnetic fusion devices is one of important issues for fusion research. Fully non-inductive plasma start-up and its maintenance up to 1h55min was successfully achieved on QUEST with a microwave of 8.2GHz, 40kW and well-controlled gas fueling and plasma-facing wall (PFW) temperature of 373K. The gas fueling is feedback controlled to keep constant in H signal, which can be an indicator of in-coming H flux to plasma facing materials (PFMs). On QUEST, the hot wall, which can be actively heated by electrical heater, was installed inside the vacuum vessel in 2014 autumn/winter (A/W) campaign, and the plasma can be sustained with high temperature PFW to investigate particle balance such as fuel recycling and wall pumping properties. Thermal insulators are installed between hot wall and vacuum vessel wall to keep the temperature of vacuum vessel wall below 423K for the protection of various diagnostics and plasma-heating devices. The function of active cooling of hot wall with cooling water channels will be installed in 2017 spring/summer (S/S) campaign. The plasma-wall interaction (PWI) is an important subject when considering SSO, and is a wide-range issue because the matters such as material science and the plasma science are linked each other complicatedly. In these matters, especially, power balance and particle balance play important roles against SSO. The power balance in long duration discharges was sufficiently investigated in TRIAM-1M, which has the world record of plasma duration on tokamaks for more than 5h16min [1]. During the long plasma discharge, all of the temperatures of PFMs are saturated and kept constant on TRIAM-1M. The power balance on QUEST is also investigated before 2014, in which the hot wall had been installed. Approximately 70%-90% of the injected power could be detected by calorimetric measurements of PFMs, and about half of the injected power was deposited on the vessel wall [2]. The total particle balance on QUEST is estimated experimentally [3]. The time evolution of wall-pumping rate is evaluated as the difference between injected and evacuated H2 flux, which are derived from the flowmeter installed on gas fueling system and a quadrupole mass analyzer (QMS) installed on the bottom of the vessel, respectively. Absolute values of them are calibrated with consideration of the pressure and volume of gas fueling line and the relationship between flowmeter and QMS signal with the situation of no plasma. The wall-stored H can be obtained by time-integration of wall-pumping rate with setting the initial integrated value at zero. On the QUEST, the wall kept at higher temperature is rather active, and almost all stored H particles are released from the wall during the intervals of plasma discharges. In the long duration discharges, the wall pumping occurs in the initial phase, and its rate gradually decrease. Finally, the wall-pumping rate becomes zero, and the wall saturation occurs. This tendency is likely to occur faster when its wall temperature is higher. To express this tendency, a wall model with hydrogen barrier (HB) which is formed around boundary between the deposition layer and the substrate was proposed [4]. In this model, the time derivative of the number of H dissolved in wall (dHW/dt) is proportional to the square of HW, when the number of H trapped in defects (HT) can be negligible. The parabolic relation between dHW/dt and HW is clearly observed in low HW experimentally, and the given curves with this model is well-fitted to the experimental observation. References [1] H.Zushi, et al, Steady-state tokamak operation, ITB transition and sustainment and ECCD experiments in TRIAM-1M, Nuclear Fusion, 45 (2005) S142-S156 [2] K.Hanada, et al, Power Balance Estimation in Long Duration Discharge on QUEST, Plasma Science and Technology, 18 (2016) 1069-1075. [3] K. Hanada, et al, Investigation of hydrogen recycling property and its control with hot wall in long duration discharges on QUEST, Nuclear Fusion, (2017) to be published. [4] K. Hanada, et al, Particle balance in long duration RF driven plasmas on QUEST, Journal of Nuclear Materials, 463 (2015) 1084-1086..
17.	長谷川真, QUESTグループ, QUEST定常プラズマの統合制御, 第１４回QUEST研究会, 2017.07, ●QUESTにおける制御システム ●長時間用プラズマ同定と制御 ●粒子供給フィードバック制御 ●高温壁の温度制御とその他 ●まとめ.
18.	長谷川真, QUESTグループ, QUESTにおける定常実験に向けた制御, RIAMフォーラム２０１７, 2017.06, QUESTにおける定常プラズマ実験に向けた制御 核融合力学部門 プラズマ表面相互作用分野 　長谷川真 トカマク装置など磁場閉じ込め式核融合装置において、統合的にプラズマを制御して定常運転を実現することは非常に重要な課題である。QUEST装置では、この課題解決に精力的に取り組んでおり、温度を制御することができる高温壁をプラズマ対向壁として有していることが装置の特徴の一つとして挙げられる。定常運転では、プラズマ対向壁の温度が非常に大きな役割を持ち、たとえば２００℃の壁の温度でのプラズマ放電においては、壁の粒子吸蔵量が増えてくると、１２０℃の場合に比べて壁排気量が下がることが実験的に示されている[1]。現在までにQUEST装置では壁の温度を１２０℃に保ったまま、４０kW程度の加熱入力パワーで１時間５５分に及ぶ長時間放電を実現しているが、今後更にプラズマの加熱入力パワーを増やして、主プラズマが高密度、高温度の領域においても本課題に取り組む予定である。 QUESTの高温壁には、壁の温度を高温に保つためのシースヒーターが内蔵されており、シーケンサーを用いて壁の温度をモニターしつつシースヒーターの消費電力を調整して温度をフィードバック制御する加熱システムが２０１４年に実装されている。一方、プラズマの加熱入力パワーが増えて壁への熱入力が増えてくると、加熱システムは、温度を一定に保とうとした場合、ヒーターの消費電力を下げてき、遂にはゼロにするが、更にプラズマの加熱入力パワーが増える場合には、逆に冷却する機構が必要になる。この冷却に求められる能力として、数十kW程度を見込んでおり、空気冷却では冷却能力が足りず、直接接触する水冷却では過大になると予想されることから、伝熱板を介して冷却管をパネルに接触させる間接冷却の機構が採用されている。本方式の実際の冷却能力等は今後調査していくことになるが、この冷却では電動バルブを開閉することで、冷却の有無を調節する。この調節には加熱システムや中央制御システム、またプラズマ制御システムなど、各機器間の連係動作が必要になる。講演では、これら加熱・冷却システムの紹介や、プラズマを長時間維持するための、いくつかの取り組みについて紹介する。 [1] 26th IAEA Fusion Energy Conference, EX/P4-49, K. Hanada, et. al..
19.	Makoto Hasegawa, and QUEST group, Modifications of Plasma Control System and Central Control System for Integrated Control of Long Plasma Sustainment on QUEST, 11th IAEA Technical Meeting (TM) on the Control, Data acquisition and Remote Participation for Fusion Research, 2017.05, [URL], Modifications of Plasma Control System and Central Control System for Integrated Control of Long Plasma Sustainment on QUEST Makoto Hasegawa1, Kazuo Nakamura1, Kazuaki Hanada1, Shoji Kawasaki1, Arseniy Kuzmin1, Hiroshi Idei1, Kazutoshi Tokunaga1, Yoshihiko Nagashima1, Takumi Onchi1, Kengoh Kuroda1, Osamu Watanabe1, Aki Higashijima1, and Takahiro Nagata1 1Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka, Japan hasegawa@triam.kyushu-u.ac.jp, nakamura@triam.kyushu-u.ac.jp, hanada@triam.kyushu-u.ac.jp, kawasaki@triam.kyushu-u.ac.jp, kuzmin@triam.kyushu-u.ac.jp, idei@triam.kyushu-u.ac.jp, tokunaga@riam.kyushu-u.ac.jp, nagashima@triam.kyushu-u.ac.jp, onchi@triam.kyushu-u.ac.jp, kuroda@triam.kyushu-u.ac.jp, rwata@riam.kyushu-u.ac.jp, higashi@triam.kyushu-u.ac.jp, nagata@triam.kyushu-u.ac.jp Achievement of steady state operation (SSO) is one of important issues for future magnetic fusion devices. The world record of plasma duration on tokamaks for more than 5h16min was achieved in TRIAM-1M [1], where particle balance and power balance are investigated. On QUEST, which is a middle sized spherical tokamak installed on the same place after the closing of TRIAM-1M experiments, these issues are also vigorously investigated, and the fully non-inductive plasma start-up and its maintenance up to 1h55min was successfully achieved [2] with a microwave of 8.2 GHz, 40 kW and well-controlled gas fueling and plasma facing wall (PFW) temperature of 373 K. On QUEST, the hot wall which can be actively heated by electrical heaters was installed inside vacuum vessel in 2014, and the plasma discharge is sustained with high temperature PFW to investigate particle balance such as wall pumping properties. The function of active cooling for hot wall with the cooling water will be installed in 2017 spring. These controls of heating with electrical heaters and cooling with cooling water will be managed by the central control system and its peripheral subsystems with the coordination of them. On the other hand, the gas fueling during plasma discharge is feed-back controlled with referring to the signal level of H which is an indicator of in-coming H flux to PFWs. This control is managed by a Proportional-Integral-Differential (PID) control on the plasma control system using a mass-flow controller. The modifications and coordination of these control systems for long discharges are introduced. 1. H.Zushi, et al, “Steady-state tokamak operation, ITB transition and sustainment and ECCD experiments in TRIAM-1M”, Nuclear Fusion, 45 (2005) S142-S156. 2. K. Hanada, et al, Investigation of hydrogen recycling property and its control with hot wall in long duration discharges on QUEST, Nuclear Fusion, (2017) to be published..
20.	長谷川真, QUESTにおける制御システムの現状紹介と展望, 第１３回QUEST研究会, 2017.02, ●QUESTにおける制御システム ●プラズマ制御システムの紹介 　・構成、仕様、機能など 　・FPGAの使用例 ●中央制御システムの紹介 　・構成、現状の課題など 　・システムへの実装例の紹介 ●まとめ.
21.	長谷川真, プラズマ境界力学実験装置QUESTにおけるFPGA利用の現状紹介, 核融合・加速器科学分野合同計測技術ワークショップ, 2016.10, [URL], QUEST装置の紹介 LabVIEW言語でのFPGA開発 FPGAの利用例 TFコイルの電気抵抗値監視 磁気計測 プラズマの電子密度計測 トリガー遅延分配器 まとめ.
22.	Makoto Hasegawa, Integrated control system on spherical tokamaks, 4th A3 Foresight Summer School and Workshop on Spherical Torus (ST), 2016.08.
23.	Makoto Hasegawa, Kazuo Nakamura, hideki zushi, kazuaki hanada, Akihide Fujisawa, KAZUTOSHI TOKUNAGA, Hiroshi Idei, Yoshihiko Nagashima, Aki Higashijima, Shoji Kawasaki, Hisatoshi Nakashima, Aleksandrovich Arseniy Kuzmin, Takumi Onchi, Osamu Watanabe, Kishore Mishra, Real-time identification of plasma current and its position with hall sensors for long-pulse operation on QUEST, 8th IAEA Technical Meeting on "Steady State Operation of Magnetic Fusion Devices", 2015.05, [URL], For long-pulse operation, the control of plasma current and its position is important to manage the heat loads, particle flux, and so on. Thus, the plasma current and its position have to be identified correctly during a long plasma discharge in real time. The plasma current and its position are usually calculated with signals of a rogowski coil sensor, magnetic flux loop sensors, and magnetic pick-up coil sensors. In order to calculate with these signals, the time-integrations of raw signals with electrical circuits or numerical calculations are required. However, these time-integrations cause drift errors which become larger according to the duration of the plasma discharge. And, this disturbs the correct identification and the control of a long-pulse plasma discharge. We propose the use of hall sensors for the long-pulse operation. A hall sensor does not require time-integration, and does not cause the drift error. On QUEST, several hall sensors are installed on the outside of the vacuum vessel. Although the quick behavior of plasma cannot be sensed with hall sensors because of eddy current effects, this enables high-accuracy measurements with the static environment of no plasma, no RF, and no vacuum. This also enables the repair or replacement of hall sensors without a vacuum purge. The plasma current and its position are identified in real time with these hall sensor signals. The plasma position and current are calculated by the evaluation of intensity ratios and intensities itself, respectively. .
24.	Makoto Hasegawa, Kazuo Nakamura, hideki zushi, kazuaki hanada, Akihide Fujisawa, KAZUTOSHI TOKUNAGA, Hiroshi Idei, Yoshihiko Nagashima, Shoji Kawasaki, Hisatoshi Nakashima, Aki Higashijima, Current Status and Prospect of Plasma Control System for Steady-state Operation on QUEST, 10th IAEA Technical Meeting on Control, Data Acquisition and Remote Participation for Fusion Research, 2015.04, [URL], Plasma control system (PCS) on QUEST has been developed for the achievement of the steady-state sustainment of tokamak plasma. QUEST is a spherical tokamak [1], on which high temperature all metal vessel wall up to 500 K is planned for the steady-state operation under unity recycling ratio. Achievement of steady-state operation in tokamak plasma is one of a key issue to realize cost-effective fusion power plants. In the aim of this, many kind of controls are required such as plasma position and its shape control, particle balance control, and heat load control. Current status and prospect of PCS for steady-state operation on QUEST are described. For the control of plasma position and its shape, these parameters have to be identified in real time and steadily. Though magnetic sensors of rogowski coils, pick-up coils, and flux loops are usually used for this identification, these sensors are not suitable for the long time measurements because drift error induced by time integration occurs. On QUEST, in addition to these sensors, hall sensors are used, which are suitable for the long time measurement because of no drift errors. Furthermore, hall sensors can be expected to have an ease of maintenance and high accuracy because these are located on the outside of vacuum vessel wall where is less noisy environment compared to the inside one. The plasma current and position are calculated with just hall sensor signals, assuming the plasma as a filament current located on the inside of vacuum vessel. In this procedure, the plasma position and plasma current are evaluated with ratios and intensities of hall sensor signals, respectively. In addition to this, plasma shape is also evaluated in real time with a shape identification method [2]. These procedures are applicable to the control of plasma position and its shape for steady-state operation. For the control of particle balance, a fueling feed-back control is implemented, which is referring Ha signals instead of plasma density. The fueling gas is puffed when an actual Ha signal intensity is lower the target intensity, and the actual signal gradually comes close to the target signal with a setting of the pulse prohibited duration. The actual Ha signal is well controlled with this method on over 10 minutes plasma discharge. Other several approaches such as a distributing system for steady-state operation will be discussed. 1. K. Hanada, K. Sato, H. Zushi, K. Nakamura, M. Sakamoto, H. Idei, et al., “Steady-State Operation Scenario and the First Experimental Result on QUEST”, Plasma and Fusion Research, 5, S1007 (2010). 2. M. Hasegawa, K. Nakamura, H. Zushi, K. Hanada, a. Fujisawa, K. Matsuoka, et al., “Development of plasma control system for divertor configuration on QUEST”, Fusion Engineering and Design, 88, 1074–1077 (2013). .
25.	長谷川 真, プラズマ統合制御に向けた制御システムの開発, QUEST研究会, 2015.03, QUEST装置における制御システムの現状と展望の紹介.
26.	Makoto Hasegawa, Kazuo Nakamura, hideki zushi, kazuaki hanada, Akihide Fujisawa, Osamu Mitarai, KAZUTOSHI TOKUNAGA, Hiroshi Idei, Yoshihiko Nagashima, Shoji Kawasaki, Hisatoshi Nakashima, Aki Higashijima, Development of high performance control system by decentralization with reflective memory on QUEST, 28th Symposium on Fusion Technology, 2014.10, [URL], Plasma control systems for tokamak plasmas are required to make control signals in real-time with simultaneously acquiring various data and calculating meaningful physical quantities. Since the physical quantities and the control signals have relationship with each other, a centralized control system is principally desirable for the grasp of these parameters. However, the computational loads on the CPU of plasma control workstation (WS) become too large to build a highly integrated control system, because it makes difficult to execute in real-time. In actual, the CPU utilization of the WS for the spherical tokamak QUEST becomes almost full. We propose to develop a decentralized control system. In this system, each control system has a reflective memory connected to each other with optical fibers, and shares various data via reflective memory. The good point of this system is to increase the CPU resource. Furthermore, the electrical insulation is ensured spontaneously. On the other hand, the synchronization accuracy between each system may become worse. The GE cPCI-5565PIORC of National Instruments Corporation is used as the reflective memory, which has 256 Mbytes memory and 170Mbyte/sec transfer rate. The most popular data type to share is double-precision real type (DBL) which needs 8 bytes to represent. The actual data read or write time is measured. Especially, within the period of 4 kHz which is the period of WS, more than 1000 to 2000 DBLs can be read or write. This means about 50 Mbytes/sec transfer rate for the one directional data sharing. For the bidirectional data sharing, each system has to repeat the read-write procedure. This would take more time. In the presentation, we will introduce the actual implementation of the reflective memory to the decentralized control system and its performance..
27.	Makoto Hasegawa, Kazuo Nakamura, Hideki Zushi, Kazuaki Hanada, Akihide Fujisawa, Keisuke Matsuoka, Hiroshi Idei, Yoshihiko Nagashima, Kazutoshi Tokunaga, Shoji Kawasaki, Hisatoshi Nakashima, Aki Higashijima, Development of plasma control system for steady state operation on QUEST, 9th Asia Plasma and Fusion Association Conference, 2013.11, [URL], A long time plasma sustainment is an important issue for the future nuclear fusion plasma. In QUEST (Q-shu university experiment with steady-state spherical tokamak), a steady state operation is also one of project objectives. Thus, the long time identification and its control of the plasma position and its shape are important for the steady state operation. However, the long time identification is difficult, as long as the integrated magnetic signals such as magnetic fluxes or magnetic fields are used because the integration errors, namely, drift errors occur and prevent the accurate identification. The WS is composed of PXI systems of the National Instruments Corporation, which contains a controller module (2.26 GHz Intel Core 2 Quad processor, memory: 2 GBytes) based on a real-time operating system, one DIO module (16-channel digital input and output), and six FPGA modules (eight-channel analog input and output in each module). In the WS, the several tasks can be performed in parallel because a multi-quad-core processor is used in the controller module. One task is for the control of a DIO module and FPGA modules. Another task, referred to as a main loop, is for the calculation of control signals by the acquired data. These two tasks are performed at 4 kHz. In addition, the real-time equilibrium calculation and the plasma image analysis are executed in parallel on other cores, respectively. The calculation period of the image analysis will be several seconds. That is sufficient to correct the drifts of magnetic fluxes. In this presentation, the development status of this control system will be introduced. .
28.	長谷川 真, Development of real-time equilibrium control system on QUEST, Workshop on QUEST and Related ST RF Startup and Sustainment Plasma Research, 2013.02.
29.	長谷川 真, 御手洗 修, 中村 一男, QUESTにおけるリアルタイム平衡計算とその制御, 平成２４年度双方向型共同研究成果報告会, 2013.01, [URL], リアルタイム用平衡計算コードの開発を行った。本コードの1回の計算時間はメッシュ数30×48の場合において2msec以内に収まると予想される。今後、この平衡計算コードの収束性や妥当性を検証するために、リミター配位やダイバータ配位など幾つかの放電パターンに対して計算を行い、実験データ及び他の平衡計算コードとの比較等を行うなどして、より詳細に吟味し、QUESTの制御システムに実装していく予定である。また、制御においては、現状はプラズマ内側エッジ位置のみの制御であるので、形状制御と呼ぶに十分な制御可能個所の個数を増やす予定である。また、プラズマ形状だけでなく、ストライクポイント等のリアルタイム同定を行い、熱負荷制御等に資する予定である。.
30.	Makoto Hasegawa, Kazuo Nakamura, hideki zushi, kazuaki hanada, Akihide Fujisawa, Keisuke Matsuoka, Osamu Mitarai, Hiroshi Idei, Yoshihiko Nagashima, Kazutoshi Tokunaga, Shoji Kawasaki, Hisatoshi Nakashima, Aki Higashijima, Development of plasma control system for divertor configuration on QUEST, 27th Symposium on Fusion Technology (SOFT 2012), 2012.09, [URL], A plasma control system in order to sustain divertor configurations is developed on QUEST (Q-shu university experiment with steady-state spherical tokamak). Magnetic fluxes are numerically integrated by 100 kHz frequency with usage of FPGA (Field-Programmable Gate Array) modules, and transferred to a main calculation loop with 4 kHz. With these signals, plasma shapes are identified in real time with 2 kHz frequency under the assumption that the plasma current can be represented as one filament current. This calculation is done in another calculation loop in parallel by taking advantage of a multi-core processor of the plasma control system. The inside and outside plasma edge position controls are tested using PID (proportional–integral–derivative) control loops for target positions. Whereas the outside edge position can not be controlled by outer PF coil current, the inside edge position can be controlled by inner PF coil current..
31.	Makoto Hasegawa, Kazuo Nakamura, KAZUTOSHI TOKUNAGA, hideki zushi, kazuaki hanada, Akihide Fujisawa, Hiroshi Idei, Shoji Kawasaki, Hisatoshi Nakashima, Aki Higashijima, Development of Control System for Divertor Configuration on QUEST, 16th International Workshop on Spherical Torus (ISTW2011), 2011.09, [URL], In a similar way to other spherical tokamaks, the achievement of steady state operation with divertor configuration is one of important issues for the QUEST project. The control system for this has been developed in the QUEST. The identification of plasma position and its configuration is required for the control. One of the methods adopted in this control system is to adjust plasma shape parameters such as elongation and triangularity directly so that the calculated magnetic signals become the same values as measured ones. Although this method cannot be adopted if the plasma shape is complicated, one can expect that the time to calculate become short because there is no need to calculate values such as flux values at inside area of vacuum vessel but just installed positions of magnetic sensors. This calculation method has been installed into the control system of the QUEST which is composed of 4 CPU cores and Real Time-OS and operates main control loop with 4 kHz period. And, this calculation with 22 flux loop signals is finished within 1msec by using parallel processing technology. The horizontal and vertical plasma positions are controlled by active coils called HCUL coils and PF26 coils, respectively with simple PID control method. The current of PF26 coils changes not only vertical magnetic field but n-index. Furthermore, the n-index also varies gradually in the process that plasma configuration changes from limiter configuration to divertor configuration. This change affects vertical control, and the appropriate PID gain values differ by each magnetic configuration. For this, the mechanism to regulate each gain values automatically according to the magnetic configuration will be also installed into the control system. .
32.	長谷川 真, QUEST実験におけるSNET利用の現状紹介, 平成22年度NIFS共同研究　SNET／核融合バーチャルラボラトリ 合同研究会, 2011.02, [URL].
33.	長谷川 真, QUEST計画における共同研究環境の構築, NIFS共同研究「SNETを用いた共同研究の進展」「核融合実験に関するバーチャル・ラボラトリー研究会」合同研究会, 2010.02.
34.	長谷川 真, 図子 秀樹, 花田 和明, 中村 一男, 藤澤 彰英, 坂本 瑞樹, 出射 浩, 東園 雄太, 川﨑 昌二, 中島 寿年, 東島 亜紀, プラズマ立上げと定常運転に向けた統合的な最適制御手法の確立, 九州大学総理工セミナー, 2009.12.
35.	長谷川 真, 中西 秀哉, 長山 好夫, 山本 孝志, 江本 雅彦, 東島 亜紀, 中村 一男, QUESTグループ, QUEST実験におけるSINET活用事例の紹介 , 学術認証フェデレーション及びSINETサービス説明会, 2009.12.
36.	長谷川真, QUEST実験におけるSNETの利用, NIFS共同研究「SNETを用いた共同研究の進展」「核融合実験に関するバーチャル・ラボラトリー研究会」, 2009.02.
37.	長谷川真, QＵESTの制御, 電気学会ST調査専門委員会, 2008.09.
38.	長谷川真, QUESTデータの取り扱いについて-QUEST実験データ閲覧システムの現状について-, 第2回QUEST研究会, 2008.07.
39.	長谷川真、中村一男、東島亜紀, QUEST制御システムの開発, バーチャルラボラトリ研究会 核融合データ処理研究会, 2008.02.
40.	長谷川真、中西秀哉、中村一男、東島亜紀, LHDおよび九州大学プラズマ境界力学装置での遠隔実験・シミュレーション, 平成19年度第1回 SNETタスク会合「SNETを用いた共同研究の進展」, 2008.02.
41.	M. Hasegawa, K. Nakamura, A. Higashijima, S. Kawasaki, H. Nakashima, K. N. Sato, H. Zushi, K. Hanada, M. Sakamoto, H. Idei, High Accessible Experimental Information on CPD Experiment, Sixth IAEA Technical Meeting on Control, Data Acquisition, and Remote Participation for Fusion Research, 2007.06.
42.	長谷川　真、坂本　瑞樹、出射　浩、中村　一男、花田　和明、図子　秀樹、佐藤　浩之助、＊高瀬　雄一、朝倉　伸幸、清水　勝宏, SOLDORを用いたQUESTダイバータ設計, プラズマ・核融合学会, 2006.11.
43.	長谷川真、坂本瑞樹、清水勝宏, QUESTにおけるダイバータシミュレーション, トライアム研究会, 2006.08.
44.	長谷川真、東島亜紀、中村一男, 全日本ST計画での計測データ処理・遠隔実験環境, NIFS共同研究「核融合実験のデータ処理に関する次世代システム技術の検討」研究会, 2006.02.
45.	長谷川真、東島亜紀、中村一男, TRIAMデータ処理系でのJavaScope利用の取組み, 次世代実験のための核融合データ処理システム技術検討作業会, 2004.05.
46.	長谷川真、中島寿年、川崎昌二、彌政敦洋、上瀧恵里子、坂本瑞樹、図子秀樹、中村一男、花田和明、伊藤智之, TRIAM-1Mにおける170GHz電子サイクロトロン波によるプラズマ生成, 日本物理学会２００２年秋季大会, 2002.09.
47.	長谷川真、トライアムグループ, TRIAM-1Mにおけるプラズマ電流立ち上げ実験, 第１５回TRIAM研究会, 2002.03.
48.	長谷川真、彌政敦洋、中島寿年、川崎昌二、上瀧恵里子、坂本瑞樹、図子秀樹、中村一男、花田和明、伊藤智之, TRIAM-1MのECH実験, プラズマ・核融合学会　九州・沖縄・山口支部第５回研究発表講演会, 2002.02.
49.	長谷川真、彌政敦洋、中島寿年、川崎昌二、上瀧恵里子、坂本瑞樹、図子秀樹、中村一男、花田和明, TRIAM-1Mにおける170GHz ECHシステムとプラズマ電流の立ち上げ実験, プラズマ・核融合学会　第１８回年会, 2001.11.
50.	M. Hasegawa, TRIAM Group, Current Startup with an ECH System on TRIAM-1M, 43rd Annual Meeting of the Division of Plasma Physics, 2001.10.
51.	長谷川真、彌政敦洋、上瀧恵里子、坂本瑞樹、図子秀樹、中村一男、花田和明、伊藤智之, TRIAM-1MにおけるOHコイルを用いないプラズマ電流立ち上げ・維持実験, 日本物理学会２００１年秋季大会, 2001.09.
52.	長谷川真、TRIAM Group, ECH Experiments on TRIAM-1M, US-JP WS on Plasma Control and Long Sustainment using RF waves, 2001.02.
53.	長谷川真、中島寿年、川崎昌二、上瀧恵里子、花田和明、坂本瑞樹、図子秀樹、中村一男、伊藤智之, TRIAM-1Mの高効率電流駆動実験, プラズマ・核融合学会　九州・沖縄・山口支部第４回研究発表講演会, 2000.12.

1.	@長谷川 真, @東島 亜紀, @新谷 一朗, @関谷 泉, @櫻井 大督, 計測データのグラフ提供サーバの構築 , 2023.04 内容および作成したコードについては、下のリンクで公開している。 https://gitlab.com/quest_dev/db_graph_plot, [URL], 共同利用・共同研究拠点である九州大学 応用力学研究所内に設置されているトカマク装置QUESTにて収集された計測データを、共同研究者等の利用者に対してWEB上でグラフ形式でデータを提供するサーバーの構築を行った。.
2.	@長谷川 真, トカマクプラズマの平衡計算コード, 2022.07 詳細な内容および作成したコードについては下のリンクにて公開している。 https://github.com/hasemac/tokamak_equilibrium, [URL], トカマク装置におけるプラズマ平衡を計算するコードであって、コイル電流やプラズマ電流、その他磁気計測値などから、もっともらしいプラズマ平衡を算出する。 また、この平衡計算コードは、特定のトカマク装置でなく一般的なトカマク装置に対して、幅広く適用できるようになっており、今後、多くのトカマク装置に対して、この平衡計算コードを適用していく予定である。.
3.	長谷川真, 櫻井大督, 東島亜紀, 新谷一郎, 松島啓二, 実験データ等を集中管理する大容量データベースの構築, 2020.12, 従来は計測データは、各計測器で計測され、各々の計測器にファイル形式で保管されることが多かった。この場合、多様なデータを総合的に解析しようとすると、各計測器に保存されているデータファイルを探し出し、それらデータを専用のソフトウェアで読み込む必要があるなど、多大な労力を必要としていた。そこで、データを集中的に保管して、データへのアクセスを統一させた大容量データベースの構築を行った。.
4.	長谷川真, 実験を安全に行うための実験設備本体室の入室管理システムの開発, 2018.01 プラズマを生成する実験設備では、安全上、プラズマ生成中は実験設備本体室の入室が禁じられている。本体室に人がいる状態で、誤ってプラズマを生成しないように警報音等の各種安全装置を設けているが、本入室管理システムもその一環に当たる。複数個所の出入り口に設置することが可能で、WiFi付ポケットサイズPCとタッチパネルを用いて省力で設置できるようにしてある。入退室時に自身の名前のボタンをタッチパネルでタッチする。中央制御装置と連動して入室者がある場合には、プラズマ生成のシーケンスは停止される。.
5.	長谷川真, 大型装置の真空排気設備のソフトウェア化とネットワーク化, 2018.01 大型実験装置QUESTにおける真空排気設備のソフトウェア化とネットワーク化を行う。ソフトウェア化では、実際の設備をよく表した操作パネルや操作スイッチをディスプレイ上に表現した。ネットワーク化では機器間の通信をEthernetで行うことで多種多様なデータが機器間で共有できるようになった。これにより、拡張や変更等に柔軟に対応できるようになった。.
6.	長谷川真, 平衡計算を用いたプラズマ形状のリアルタイム同定, 2013.11 従来、QUEST装置で用いられたプラズマ形状のリアルタイム同定の手法は、プラズマ電流を一本のフィラメント電流と仮定して、所定の位置にフィラメントを置いたときの磁束分布の計算から最外殻磁気面を算出していた。しかし実際は、プラズマ電流は分布を持つものであり、実際の状態を再現しているとは言いがたい。そこで、Grad-Shafranov方程式と呼ばれる、プラズマの力学平衡の式をリアルタイムに解いて、プラズマ位置・形状を算出するコードの開発を行った。この計算方式の特徴としては、一回のデータ入力に対して、Grad-Shafranovの式を一回計算していることにある。すなわち、一回のデータ入力に対して、イタレーション回数が１回であり、収束性を確認しないでいる。この場合、同一のデータセットが何回(～数回)も入力された場合に計算結果が収束することになる。また、本計算の際に、他の方式で計算されたプラズマ位置をプラズマ位置の束縛条件として利用することができる。これは、プラズマが極度に非等方であり、等方を仮定している平衡計算が適切ではない場合に有効であり、すくなくとも磁気計測の計測値と計算値はほぼ一致する状態での計算結果を提供する。今後、この計算により求めた最外殻磁気面と多計測による位置の比較の検証を行い、また、最外殻磁気面の制御を行うよう低である。.
7.	長谷川真, プラズマ映像による位置・形状の同定と、それによる磁気計測の補正, 2013.11 従来の磁気計測は、生信号を時間積分するため、積分時間が長くなればなるほど積分ドリフトと呼ばれるエラー量が発生していた。このため、磁気計測の結果から求められるプラズマの位置・形状を長時間にわたって同定することは難しかった。エラー量を軽減するために積分器の改良が試みられ、一定の効果が得られたものの、一度、周囲環境の温度変化やそれに伴う電子部品の特性変化などにより発生したエラー量が計測結果に混ざると、それを取り除くのは原理的に不可能である。そこで、本作品ではプラズマの画像を撮影し、その画像からプラズマの位置・形状を取得し、その情報から得られるであろう磁気計測の値を推定し、磁気計測に補正をかけることを試みている。プラズマの位置の同定方法は、現状は、グレースケールで撮影した映像に対して、ある値を境に白と黒の２値化を行い、明るい領域の図形重心を取るという方法を採用している。画像フィルターはNational Instruments Corp.より提供されているものを使用している。現状は、テスト動作を試したのみであるが、プラズマの明かりの代わりに懐中電灯を用いた試験では、プラズマの位置を同定し、その結果を下に線形に磁気計測値を補正することに成功している。実際のプラズマの位置・形状においても、National Instruments Corp.より多くの画像フィルターが提供されているので、これらを組み合わせることで同定できるものと考える。, トカマクプラズマの定常運転で問題となる磁気計測のドリフト問題の解決を試みる。ここでは、プラズマ画像からプラズマの位置・形状を同定して、それを元に計測されるであろう磁気計測の値を推定し、磁気計測の値に補正をかける。現状は、テスト動作での確認であるが、正常に動作することを確認している。.
8.	長谷川真, プラズマ形状のリアルタイム同定とその制御システムの開発, 2012.04 プラズマの形状を同定するには、プラズマからの応答である磁気の計測をプラズマ周辺で多く行うことが必要になる。このため、プラズマ制御システムの入出力チャンネル数をそれぞれ４８chから６４chへと増設した。チャンネル数の増設に伴い、サンプリング周波数等の処理速度の低下が予想されるが、DMA(Direct Memory Access)の利用や、並行実行となるコーディングの開発により、従来のサンプリング周波数を落とすことなく増設が行えている。 プラズマ形状の同定について、本作品ではプラズマ電流を一本のフィラメントと仮定して、その磁束分布を計算して最外殻磁気面位置を算出する方法を採用している。このようにすることで、形状位置の正確性はあまり保証されないが、短時間でプラズマ境界位置を計算できるという利点がある。この方法で、リアルタイムに計算することを可能にしている。 次に、一般的な形状制御ではフラックス値を参照して、そのフラックス値を制御するという方法が広く用いられている。ただ、この方法ではプラズマ境界位置とフラックス値を関係づけるのが難しいという欠点を有している。一方、本作品ではプラズマ境界位置を求め、その制御を直接行うことにしているので、より直観的な制御を可能としている。, トカマク型プラズマにおいて、プラズマ放電の長時間維持は重要な課題である。長時間維持を行うためには、プラズマを真空容器に接しないで維持させることが重要であると言われている。このためには、プラズマの形状をリアルタイムに同定して、その制御を行うことが求められる。本作品は、プラズマ形状のリアルタイム同定を行い、そのプラズマの境界位置を外部磁場コイルで制御するものであり、その形状の一部を本作品にて制御できることを確認した。.
9.	長谷川真、東島亜紀, ネットワーク通信制御ルータの構築, 2011.10 九州大学のセキュリティーポリシーで禁止されているファイル交換ソフトのP2P通信は、九大情報基盤センターでも監視しているが、かなり上流にある箇所での監視であり、P2P通信をおこなった特定の端末を探し出すことが難しい。特定の端末を探し出すためには、その端末に近い個所にあるルータで監視を行ったほうが効率的である。このため、高温プラズマ力学研究センター内にP2P通信を監視し、検出時にはその通信を遮断するルータの構築を行った。具体的には、2枚のネットワークボート(NIC)が挿入されたCentOS Linux端末を用意し、2枚のNICをブリッジ接続して透過接続を構成する。P2P通信の検出は無償で提供される「snort」によって行われる。ログ解析ツールである「swatch」を使用し、snortがP2P通信を検出したことをトリガーとして「iptables」を用いて該当IPアドレスの通信を遮断し、同時にネットワーク管理者に遮断が起きたことを電子メールで知らせている。ネットワーク管理者は、該当IPアドレスからMACアドレスを求め、該当端末を見つけだすことが可能となる。 また、センター内でのネットワーク通信では、外部研究者も自身の端末でネットワーク通信ができるように未登録端末の使用を認めている。ただし、この際には、HTTPおよびHTTPS通信といった基本的通信のみを許可するようにしている。端末を登録すると、ほぼすべてのポートを使用して外部と通信ができるようになる。このようにすることで、外部研究者の意図せぬファイル交換ソフトの使用を極力防ぎ、かつ登録端末であれば使用者への迅速な連絡が可能となる。 以上のようなルータを構築することで、センター内のネットワークセキュリティーの向上に貢献している。, 高温プラズマ力学研究センターにおけるネットワーク通信において、九州大学のセキュリティーポリシーで禁止されているファイル交換ソフトのP2P通信を監視し、検出時にはその通信を遮断する仕組みの構築を行う。また、未登録端末については、HTTPおよびHTTPS通信といった基本的通信のみを許可し、全体的にセキュリティーレベルを向上させることを目的としたルータを構築した。.
10.	川崎昌二、長谷川真, 本体室入室者監視システム, 2010.07 QUEST装置を使用した実験は、同時に多人数の人間が参加する。一方、プラズマ生成時には大電力高周波を使用し、また硬X線も発生するので、本体室に入室者がいないことを確認して、プラズマの生成を行なう必要がある。そのため、入室者の有無を表示する機器を本体室入り口に設置し、その情報を中央制御に伝えるシステムを構築した。万一、入室者がいた場合には実験シーケンスは自動的に停止するようにしてあり、安全に実験が遂行できる。.
11.	長谷川真, 電源＆コイル結線ログ記録WEBアプリケーション, 2010.02 QUEST実験ではプラズマ閉じ込めのための磁場生成として、幾つかの電源とコイルを用いている。プラズマ放電を行なった際に使用した電源及びその接続コイルとコイルターン数などの結線の情報は、後解析を行なう際に決して欠くことのできない情報である。そこで、これらの情報を実験者はWEB上に記入して記録できるようにした。その記録の閲覧も、WEBで行なうことが可能である。また、中央制御システムと連動し、少なくとも、その日の実験の最初に記録を行なわないと、実験シーケンスの起動が行なえないようにしている。このようにすることで、記録を忘れることを未然に防ぎ、確実に正確な情報を記録できるようになった。, [URL].
12.	長谷川真、東島亜紀, QUEST中央制御システム, 2010.05 球状トカマク装置QUESTにおける実験で、電源や高周波発信器など多くのサブシステムを統括する中央制御システム。サブシステムの制御を行ない、異常を監視して異常発生時には実験者に警報発呼をおこなう、もしくはシーケンスの安全な停止を行なう。また、QUEST本体室の入退室者の状況を実験者に通知したり、実験参加者にシーケンスの状態を周知するためにカウントダウン時に本体室・制御室においてメロディー発呼をおこなうなど、安全な運転を確保する機能を有するというように、QUEST装置を用いた実験に於いて基幹となるシステム。, 球状トカマク装置QUESTにおける実験で、電源や高周波発信器など多くのサブシステムを統括する中央制御システムの継続的開発.
13.	長谷川真, QUEST数値計算サイトの構築, 2009.09 QUESTの磁場構造や電子軌道などの数値計算をWEB上で行ないグラフ表示するようにしたサイト。プラズマの力学的平衡(リミタ配位、ダイバータ配位)の計算も可能であり、計算結果をContour図などで視覚的に表現する。これらの計算において使用するコイルもWEB上にて選択が可能であるので、柔軟に実験状況に即した計算が可能となり、実験パラメータの選定に指針を与え、効率的な実験・研究の推進に貢献している。, [URL].
14.	長谷川真、東島亜紀, QUEST Community Siteの構築, 2009.09 QUEST装置を用いた実験・研究において、全国の共同研究者と技術情報や学会発表、論文等の情報の双方向の共有を可能にし、QUEST実験・研究の効率化・円滑化を目的とするサイトの構築を行なう。, [URL].
15.	長谷川真, QUEST装置のプラズマ制御システム, 2008.04 QUEST装置で生成されるプラズマを集中して制御するためのシステム。各コイル電源、RF発振器、ガス供給等装置などへ指令値を出力して制御する。また、リアルタイムでプラズマ位置の同定を行い、そのフィードバック制御を行ったり、プラズマ電流をコントロールするためのRFフィードバック制御、周回電圧フィードバック制御など、多種のフィードバック制御を実装し、適宜改良し、または最適なフィードバックループの開発を行っている。今後更に、プラズマ形状制御などのフィードバック制御を実装し、また幾つかのアクチュエータとセンサー(ex. 壁ヒーター 壁温度、クライオポンプ 排気量など)を追加しダイバータ配位の定常運転に向けた改造を行なう。, QUEST装置で生成されるプラズマを集中して制御するためのシステム。プラズマの応答を計測し、それに対応して各コイル電源、RF発振器、ガス供給等装置などへ指令値を出力して制御するシステム。.
16.	長谷川真, 小型PWI実験装置CPDの制御ソフトウェア, 2007.03 小型PWI実験装置CPDにおいて、プラズマを生成、制御するためのソフトウェアであり、４つの磁場コイルのPID制御を行い、ガスパフ、高周波の入射を高精度のタイミングで制御を行う。.
17.	長谷川真, 実験ログ記録用データベース, 2004.04 プラズマ放電を行う際の種々のパラメータをWeb上にて入力し、履歴を保管するデータベースであり、Web上にて履歴の確認や、パラメータの検索等をおこない、実験の効率化を諮るデータベースである。.
18.	長谷川真, 計測データグラフ閲覧用データベース, 2004.02 プラズマ実験において収集した計測データを系統的に保管管理し、Web上にて利用者からの要求に応じてデータをグラフ化して表示、データのダウンロード、データの抽出などを行う。.

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