著者
政宗,貞男
出版者
プラズマ・核融合学会
雑誌
プラズマ・核融合学会誌
巻号頁・発行日
vol.76, no.12, 2000-12-25

The Reversed Field Pinch (RFP) has been believed to be dominated by anomalous transport due to strong magnetic fluctuations as with other low safety factor systems. However, for the last decade, RFP research has achieved significant progress in understanding its confinement physics. As a result, suppresion of the dynamo-induced fluctuations by controlling the current density profile has realized remarkable improvements in energy confinement time. Issues for near-term RFP research on the part of fusion programs includes active plasma control for confimenent improvement, stable operation for durations far exceeding the field penetration time of the conducting shell, heat and particle control, and possible optimization of the RFP configuration. Long term perspectives are also discussed.
著者
林屋,均
出版者
日本AEM学会
雑誌
日本AEM学会誌
巻号頁・発行日
vol.10, no.2, 2002-06-10

Reversed field pinch (RFP) plasmas have been formed in a TS-3 device and an ohmic heating current drive was applied to support the plasma. In such condition, it was found that the direction of the toroidal field induced by the plasma current naturally inversed. A magnetic structure was finally formed like the spherical tokamak (ST) in which the direction of the toridal field induced by the plasma current is the same as the field generated by the external coil. To understand the dynamical change of the magnetic structure in this process, the toroidal field distributions, safety factor profiles and the profiles of plasma pressure are shown. All of these results indicate the transition phenomena of the magnetic structure from REP to low q ST. This phenomenon is also consistent with the latest report from another organization (Himeji Institute of Technology).
著者
政宗 貞男 八木 康之
出版者
プラズマ・核融合学会
雑誌
プラズマ・核融合学会誌 = Journal of plasma and fusion research (ISSN:09187928)
巻号頁・発行日
vol.76, no.12, pp.1217-1226, 2000-12-25
参考文献数
62
被引用文献数
2

The Reversed Field Pinch (RFP) has been believed to be dominated by anomalous transport due to strong magnetic fluctuations as with other low safety factor systems. However, for the last decade, RFP research has achieved significant progress in understanding its confinement physics. As a result, suppresion of the dynamo-induced fluctuations by controlling the current density profile has realized remarkable improvements in energy confinement time. Issues for near-term RFP research on the part of fusion programs includes active plasma control for confimenent improvement, stable operation for durations far exceeding the field penetration time of the conducting shell, heat and particle control, and possible optimization of the RFP configuration. Long term perspectives are also discussed.
著者
平野 洋一
出版者
社団法人 プラズマ・核融合学会
雑誌
プラズマ・核融合学会誌 = Journal of plasma and fusion research (ISSN:09187928)
巻号頁・発行日
vol.75, no.5, pp.614-630, 1999-05
参考文献数
60
被引用文献数
9 9

Recent results of confinement studies and attempts to improve the confinement in reversed field pinch plasmas (RFP) are reviewed. Several scaling studies of RFP energy confinement time are summarized and the values of the confinement time of RFPs are compared with ITER−89P L-mode scaling. A new scaling law recently proposed is also described. Results of transport studies in RFPs are summarized and it is shown that the stochasticity of magnetic field lines caused by the magnetic fluctuations of dynamo action probably plays a dominant role in the core of RFP plasma. Recent Lundquist number scaling study for magnetic fluctuations is also described. Promising experimental and simulation results are introduced which are conducted to improve the RFP confinement. For examples, five-hold improvement of the energy confinement time is obtained in MST by driving the poloidal current in outer region with the pulsed poloidal current drive (PPCD). The increase of poloidal beta up to 20% is obtained in the Improved High Theta Mode in TPE−1RM20. Improved confinement by a flow shear is also observed in RFPs as in tokamaks and helical systems. Finally experimental and computational results are described which may indicate the bifurcation from the dynamo with multiple helical magnetic fluctuations to that with a single helical fluctuation through the increase of Prandtl number. In the case with a single helical fluctuation, the stochastic region caused by the over-lapping of magnetic islands can be reduced and the confinement degradation by the stochasticity of magnetic field lines may be avoided.
著者
古木 隆寛 中城 満 原田 哲夫
出版者
一般社団法人 日本科学教育学会
雑誌
日本科学教育学会研究会研究報告 (ISSN:18824684)
巻号頁・発行日
vol.32, no.8, pp.19-22, 2018-05-26 (Released:2018-07-22)
参考文献数
5

「皮膚感覚実験」では温点、冷点、触圧点、痛点の反応数を手掌、手背、脛骨前部、腓腹部の4 カ所で測る。 痛点が各場所に最も多いことが分かり、手と足では手の方が刺激に対する反応が多いことも分かった。「感覚閾値実験」では、基礎刺激量に対して閾値はほとんど同じであり、ウェーバーの法則が成り立つことを学習する。今回の実験では実験学習者の内被験者に刺激を与える側の実験実施者がいかに均一な力、速さで刺激を与えられるかが課題である。二つの実験は簡単な器具で行うことができ、さらにデータ処理の統計学的方法を学ぶ教材としては有効である。「理科離れ」が問題とされている現在で、学生たちが実際に自分たちの体を通して、感覚実験を行うことは、学生たちが生理学的な内容に興味を持つきっかけになる可能性がある。その意味で「皮膚感覚実験」および「感覚閾値実験」は学校教育現場(小学校~高等学校)において有用である。
著者
秦泉寺 久美
雑誌
情報処理
巻号頁・発行日
vol.61, no.6, pp.620-626, 2020-05-15

ディジタルディスラプションの時代に老舗企業が収益構造の変革を求められている.アジャイル開発は手段として有用なはずだか,なぜか老舗企業に積極的に採用される機運にはない.その理由は旧来型の契約制度運用にあった.ソフトウェアが継続的にデリバリされ,フィードバックによって要件が進化するアジャイル開発を安心・安全に遂行するためには準委任契約をベースに,税制,下請法,労働者派遣法などの法制度を確実に遵守できる定常運用設計が必要である.こういった制度運用を整備した結果,1年半のトライアル期間に27件の準委任契約が締結され,アジャイル開発の促進が確認できた.
著者
中村 要介 土屋 十圀
出版者
Japan Society of Civil Engineers
雑誌
水工学論文集 (ISSN:09167374)
巻号頁・発行日
vol.50, pp.361-366, 2006 (Released:2010-11-30)
参考文献数
17

This study estimated the safety degree of flood control at Yattajima, the Tone River, Japan to verify effects of additional dams. Rainfall events considered are Catherine Typhoon in 1947, Ise Bay Typhoon in 1959, the Typhoon No. 15 in 1981, and the Typhoon No. 5 in 1998. The storage function method was used for runoff analysis, which showed good agreement between observed and computed discharges. Using the spatiotemporal rainfall pattern of Catherine Typhoon, this study simulated rainfall-runoff at each time stage; 1959 with two dams, 1981 with five dams, and 1998 with six dams (the same as present situation), and evaluated the effect of these added dams on flood control in terms of the decrease of peak discharge at Yattajima. The decreases estimated were 513-1, 253 m3/s for the 1959 situation; 2, 025-2, 765 m3/s for 1981; and 2, 233-2, 973 m3/s for 1998. It is also verified that the present situation with six dams can cope with 200-year floods, which is significant improvement because the past situation without dams could cope with 100-year floods.
著者
長嶋 祐二
出版者
工学院大学
雑誌
基盤研究(A)
巻号頁・発行日
2014-04-01

本研究では、3次元アニメーションによる日本手話の形態素語彙辞書の構築を行った。辞書に収録した3次元手話動作は、光学式モーションキャプチャにより収録した。辞書の単語は、提案しているNVSG要素モデルを用いて記述されている。記法結果はSQLiteフォーマットで蓄積し、形態素辞書データベースを構築した。その結果、日本語の意味が分からなくても手話の構成要から検索可能である。共通課題であった、解析ツールでは、MAを構築し手話の音素レベルからNVSG要素モデルを用いて3次元動作記述支援システムを開発した。更に、BVHデータからリアルタイムで3次元手話アニメーションを生成する3Dビューアを開発した。