An ordered binary decision diagram (OBDD) is a graph representation of a Boolean function. It is observed that many practical Boolean functions are represented in feasible size. In this paper, the size of ordered binary decision diagrams representing threshold functions is studied. Two cases are treated: an ordering of variables is given in one case,

Electron cyclotron current drive (ECCD) experiments have been conducted in the helical heliotron device, Heliotron J. A wide configuration scan shows that the electron cyclotron (EC) driven current is strongly dependent on the magnetic ripple structure where the EC power is deposited. As the EC power is deposited on the deeper ripple bottom, the EC current flowing in the Fisch–Boozer direction decreases, and the reversal of directly measured EC driven current is observed. Measurement results using electron cyclotron emission and soft-x ray spectrum diagnostics imply that high-energy electrons are generated for ripple top heating while they are suppressed for ripple bottom heating, indicating that the generation and confinement of trapped electrons have an important role on ECCD. For ripple top heating, the typical ECCD efficiency is estimated as γ = n e I EC R/P EC = 0.8 × 1017 A W−1 m−2 and , where n e is in 1020 m−3, I EC in A, R in m, P EC in W and T e in keV. The normalized ECCD efficiency is found to be independent of the absorbed EC power for both ripple top and bottom heating cases.

JPEG2000 has been selected as the image compression and decompression technology for digital cinema by DCI(Digital Cinema Initiatives). In a few years, large amount of JPEG2000 compressed files will be widely used and delivered. Identifying a target compressed file out of image sequences or database is highly demanded. In this paper, very unique identifying method is presented. It takes advantage of the feature of JPEG2000 codestream structure. The proposed method has advantages of low computation and high accuracy over conventional methods.

In Heliotron J, low magnetic shear configuration, instabilities with frequency chirping in the frequency range of Alfvén eigenmodes have been observed in tangentially injected neutral beam plasmas. These modes are induced by energetic-particle driven magnetohydrodynamic (MHD) instabilities such as global Alfvén eigenmode or energetic particle mode. A hybrid directional Langmuir probe system has been installed into Heliotron J to investigate the response of fast-ion fluxes to the MHD modes. A high coherent response of the ion flux to the bursting modes has been observed not only by the co-directed probe but also by the counter-directed one. A linear correlation between the response of the co-directed ion flux and the mode amplitude has been found. The radial profile of the response of the co-directed ions has decreased with the minor radius and has not been obtained significantly outside last closed flux surface. These results indicate that the fast-ion response is due to a resonant convective oscillation. The ion flux response of the counter-directed probe has appeared in the growth phase of the mode burst. Its phase relation is different from that of co-directed one and magnetic probe located at the Heliotron J vacuum vessel. Two candidates of the detected ion flux of the counter-directed probe have been discussed.