著者

長山 好夫 間瀬 淳

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 (ISSN:09187928)

巻号頁・発行日

vol.81, no.5, pp.337-348, 2005 (Released:2005-07-29)

参考文献数

29

被引用文献数

2 2

---

Present status of the development of microwave imaging diagnostics is presented. Electron cyclotron emission imaging (ECEI) is useful to obtain 2-D cross-sectional view of electron temperature. Microwave imaging reflectometer (MIR) is useful to obtain 2-D picture of electron density fluctuation. They will be powerful tool to study localized magnetohydrodynamic (MHD) instability and micro instability, which cause turbulence in plasma. Microwave imaging sensor is key technology, and several types of antenna array with Schottky barrier diodes have been developed. In order to reduce the size and cost, microwave circuits on board have been also developed. Microwave imaging diagnostics are now installed in LHD and TEXTOR. Comparison between the ECEI in TEXTOR to the rotational ECE imaging in TFTR shows advantages of ECEI.

著者

小方 厚

出版者

社団法人 プラズマ・核融合学会

雑誌

核融合研究 (ISSN:04512375)

巻号頁・発行日

vol.47, no.4, pp.373-400, 1982 (Released:2011-08-16)

参考文献数

47

---

プラズマ実験のデータ処理を解説し鳥3部からなる論文の第2部である。内容を以下に示す。§4データの再生 (1) 較正と補正 (2) 逆変換 (3) アーベル変換とトモグラフィ;§5データのあてはめ (1) 最小2乗法 (2) 重回帰分析と直交関数展開 (3) あてはめの良さ。なお, 第一部の内容は§1はじめに, §2データ収集, §3データの前処理」また, 第三部の内容予定は§6データの直交関数展開, §7データの記憶と検索, §8 おわりに」である。

著者

野田 哲二

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 (ISSN:09187928)

巻号頁・発行日

vol.79, no.5, pp.452-459, 2003 (Released:2005-09-28)

参考文献数

30

被引用文献数

3 4

---

The evaluation of induced activity in a fusion system was made. The activity at the first wall and blanket structures are critical from the viewpoint of environmental safety and materials for low activation should be developed. The present status of development of candidate materials such as ferritic steels, vanadium alloys and SiC composites are viewed. Furthermore, isotope controlled materials and annihilation of radioactive nuclides are discussed.

著者

長谷川 晃

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 (ISSN:09187928)

巻号頁・発行日

vol.80, no.1, pp.24-30, 2004 (Released:2004-06-16)

参考文献数

31

被引用文献数

2 4

---

Irradiation effects of SiC fiber reinforced SiC matrix composites were summarized. Based on studies of irradiation behavior of SiC⁄SiC composites, SiC fibers which have stoichiometric composition and highly crystallized structure are expected to have high resistance to irradiation, and advanced SiC⁄SiC composites for fusion application were developed using these advanced SiC fibers. In this paper, the mechanism of irradiation resistance and recent irradiation studies on size stability, mechanical properties and thermal diffusivity were introduced.

著者

中井 貞雄 山中 千代衛

出版者

社団法人 プラズマ・核融合学会

雑誌

核融合研究 (ISSN:04512375)

巻号頁・発行日

vol.13, no.3, pp.312-323, 1964 (Released:2011-03-04)

参考文献数

14

---

For the origin of the precursor electron in the E-M shock tube, various hypotheses were proposed by many authors. But up to now there is no definite conclusion of its origin nor the informations of its density. Now we report the axial distribution of the precursor electron in a T-shaped shock tube which has been measured by using the automatic measuring apparatus of the microwave reflection coefficient.

著者

阿部 純義

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 (ISSN:09187928)

巻号頁・発行日

vol.78, no.1, pp.36-44, 2002 (Released:2005-12-08)

参考文献数

23

被引用文献数

5 5

---

Boltzmann-Gibbs statistical mechanics is known to exhibit fundamental difficulties when a system under consideration contains long-range interactions. Tsallis' nonextensive statistical mechanics offers a consistent theoretical framework for treatment of such a system. In this article, an approach to statistically describing pure-electron plasma based on the Tsallis entropy is reviewed and related problems are discussed.

著者

岩切 宏友

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.81, no.1, pp.19-24, 2005-01-25

参考文献数

25

被引用文献数

1

---

To investigate the fundamental effects of the helium irradiation on metallic materials, transmission electron microscope (TEM) observation, surface observation using scanning probe microscope (SPM), and hardness measurements of the damaged region were carried out. Effects of pre-irradiation of helium ions on trapping of injected deuterium have also been examined. Several important experiment findings are briefly explained. These results emphasized that the formation of helium bubbles is a critical factor in understanding the plasma-surface interaction in fusion reactors.

著者

河崎 善一郎

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.80, no.7, pp.589-596, 2004-07-25

参考文献数

24

被引用文献数

1

---

Investigation of lightning discharges has about 250 years history. During these 250 years we have accumulated the knowledge, and the understanding of lightning physics has been done qualitatively. According to the author's understanding our interpretation and understanding about lightning physics is not sufficient. Moreover still we have newly discovered phenomena related with lightning discharge, like discharges from thundercloud top to the ionosphere named RedSprite. The investigation on lightning physics can be concluded as one of the attractive subjects, though it has long history.

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

北川 米喜 千徳 靖彦 田中 和夫 児玉 了祐 西村 博明 中井 光男 乗松 孝好 砂原 淳

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 (ISSN:09187928)

巻号頁・発行日

vol.81, no.5, pp.384-390, 2005 (Released:2005-07-29)

参考文献数

24

被引用文献数

1 2

---

An uniformly imploded deuterated polystyrene (CD) shell target is fast-heated by a Petawatt (PW) laser without cone guide. The best illumination timing is found to be in a narrow region around 80±20 picoseconds from the onset of the stagnation phase, where thermal neutrons are enhanced four to five times by the PW laser of energy less than 10% of the implosion laser. The timing agrees with the timings of enhancement of the X-ray emission from the core and reduction of the Bremsstrahlung radiation from scattered hot electrons. The PW laser, focused to the critical density point, generates the energetic electrons within so narrow angle as 30º, which heats the imploded CD shell, of which the internal energy is 50 J, to enhance thermal neutrons. The increment of the internal energy is 15 J, which seems to agree with the energy reduction of the hot electrons. These results first show that the PW laser directly heats the imploded core without any cone-like laser guide.

著者

中村 幸治 芳野 隆治 Robert GRANETS Gabriella PAUTASSO Otto GRUBER Stephen JARDIN

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 (ISSN:09187928)

巻号頁・発行日

vol.78, no.4, pp.347-355, 2002 (Released:2005-12-08)

参考文献数

31

---

Validation studies of a neutrally balanced vertical plasma position, so-called ”neutral point”, have been carried out by computational simulations and experiments under trilateral Japan-US-EU collaborations. It was clarified that the neutral point, where VDEs (Vertical Displacement Events) are hardly occurred, does exit in the Alcator C-Mod and ASDEX-Upgrade tokamaks as well as the JT-60U, consistent with the simulations. Meanwhile, precise details of the VDE behavior exhibit their own characters according to the individual ofthe tokamaks such as an up-down asymmetry of plasma shape. Sensitivity of the neutral point to the plasma shape and current profile was also addressed in detail.

著者

吉田 善章

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 (ISSN:09187928)

巻号頁・発行日

vol.78, no.8, pp.788-791, 2002 (Released:2005-12-08)

参考文献数

2

---

The Navier-Stokes (NS) system of equations is a central paradigm of nonlinear partial differential equations describing nonintegrable dynamics. The mathematical analysis of the NS system invokes a priori estimates for the energy and enstrophy. The difficulty stemming from the vortex-tube stretching effect is explained. By replacing the convective nonlinear term by a random noise term, one can develop a statistical model of turbulence. The mathematical framework of such modeling is also reviewed.

著者

神野 雅文 本村 英樹

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 (ISSN:09187928)

巻号頁・発行日

vol.81, no.10, pp.807-809, 2005 (Released:2005-11-28)

参考文献数

12

被引用文献数

1 2

---

As interests in environmental friendly products, demands from market for mercury-free fluorescent lamps become stronger. Xenon is the most expected material as a substitution for mercury for fluorescent lamps. So many researches have been done by so many researchers and recently by using external electrode with conventional discharge tube with internal electrodes droved by pulsed discharge has achieved 90 lm/W and 12000 cd/m2. Another effort is using molecular gas as discharge medium. For example Ar-N2 mixture and CO are proposed.

著者

市川 芳彦

出版者

社団法人 プラズマ・核融合学会

雑誌

核融合研究 (ISSN:04512375)

巻号頁・発行日

vol.4, no.5, pp.440-457, 1960 (Released:2011-03-23)

参考文献数

17

著者

竹田 辰興 彌政 敦洋

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 (ISSN:09187928)

巻号頁・発行日

vol.78, no.9, pp.842-856, 2002 (Released:2005-12-08)

参考文献数

57

---

Applications of neural networks to data analysis and control of fusion plasmas are reviewed. First, a brief introduction to the general features of a neural network is presented, where the neural network is considered as a continuous mapping device, a classification device, a statistical processing device, and a time series predicition device. Then, the applications of neural networks to the research field are explained where the problems to be solved are classified a sfitting function, shaping an experimentally obtained spectrum, analyzing equilibrium quantity, prediction, tomography, and control problems. Throughout the article, we restrict ourselves to description of applications of multi-layer neural networks.

著者

高橋 亮人

出版者

社団法人 プラズマ・核融合学会

雑誌

核融合研究 (ISSN:04512375)

巻号頁・発行日

vol.68, no.4, pp.360-367, 1992-10-25 (Released:2010-10-22)

参考文献数

14

被引用文献数

1

---

Recent progress of “cold fusion” research is reviewed.Accumulated experimental results in these three years since March 1989 are classified as 1) weak neutron emission, 2) tritium generation with anomalous n/T ratio, 3) charged particle emission with anomality, 4) He-4 generation, 5) large excess heat generation and 6) anomalous enhancement of D/Pd ratio.Resutls of 1) through 4) suggest the existence of unclarified nuclear reactions in Pd (or Ti) /Deuterium systems.Relation between excess heat and nuclear products is yet to be clarified.Subjectives of further research are mentioned.

著者

堀田 栄喜 ポンチャイ カーンパーニット 林 泉

出版者

社団法人 プラズマ・核融合学会

雑誌

核融合研究 (ISSN:04512375)

巻号頁・発行日

vol.44, no.2, pp.115-124, 1980

---

Dynamic stabilization of high beta plasmas by axial rf current has been theoretically investigated. It is shown that higher-number modes are very easy to be stabilized. In case of m=1 mode, if there is no conducting shell, the shorter wave-length instabilities can be stabilized, but the stabilized wave-number region is very narrow. When the plasma column is surrounded by a concentric conducting shell, however, the stabilizing force of the rf image current induced in the conducting shell is so effective that the long wave-length m=1 mode can be perfectly stabilized by very small rf current.

著者

本島 修 大西 正視 飯吉 厚夫

出版者

社団法人 プラズマ・核融合学会

雑誌

核融合研究 (ISSN:04512375)

巻号頁・発行日

vol.38, no.2, pp.205-223, 1977 (Released:2011-03-04)

参考文献数

14

---

We propose the possibility to ignite the D-D reactor from the D-T reactor by increasing the deuterium density and reducing the tritium density. Supposing that the D-T reactor has been already realized and the plasma parameters are in the Trapped Ion Regime, the D-D reactor is possibly ignited by continuously developing the plasma parameters from the D-T reactor. The dynamics of the transition is calculated, and it becomes clear that the additional heating in the initial state is very effective. The characteristics of the D-D reactor are also shown. The loss rate of tritium from the core plasma is one order less than that of the conventional D-T reactor. At last the modified D-T reactor which is aimed to improve the tritium breeding ratio in the Li blanket is introduced.

著者

横山 昌弘 井沢 靖和 山中 千代衛

出版者

社団法人 プラズマ・核融合学会

雑誌

核融合研究 (ISSN:04512375)

巻号頁・発行日

vol.15, no.3, pp.217-223, 1965 (Released:2011-03-04)

参考文献数

9

著者

中島 徳嘉 佐貫 平二 岡本 正雄 藤原 正巳

出版者

社団法人 プラズマ・核融合学会

雑誌

核融合研究 (ISSN:04512375)

巻号頁・発行日

vol.66, no.6, pp.631-662, 1991-12-20 (Released:2010-10-22)

参考文献数

38

被引用文献数

3 2

---

Single particle confinement or particle orbit and collisional diffusion are reviewed for general toroidal systems. The single particle confinement or particle orbit is described using the guiding center approximation. Effects of the radial electric field are also considered. Neoclassical features are explained intuitively by using the characteristics of the single particle orbits and effective Coulomb collision frequencies. As an advanced treatment, the neoclassical theory is systematically given on the basis of the moment approach.