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A new method is proposed to analyze mode contents of high power electromagnetic waves that are propagating through corrugated waveguides in the electron cyclotron resonance heating (ECH) system for nuclear fusion devices. The method was applied to a 168 GHz transmission line of the ECH system in Large Helical Device (LHD) to evaluate the waveguide misalignment. Mode contents of the propagating wave could be well obtained, and the wave field in the waveguide was reconstructed by using the information of each mode.

We developed 8 times 8 beam-deflecting optical switch with a switching speed within one microsecond utilizing electro-optic effect of PLZT. A newly-developed radial optical path design and putting-in packaging structure with a monolithic PLC platform were applied.

There are several important roles for the electron cyclotron resonance heating (ECRH) methods in helical-type plasma experimental devices. One is to produce high-temperature and high-density current-free plasmas. Another is additional heating of electrons and resulting ion heating through equipartition. Plasma temperature and current profile controls with highly localized heating become advanced techniques to improve plasma confinement and to suppress some MHD instabilities. ECRH is also an ultimate candidate of a steady-state plasma sustainment.

We developed a 4/spl times/4 high-speed optical switch subsystem with variable optical attenuation (VOA). This switch subsystem allows high-speed level adjustment as well as high-speed switching by using the electro-optic (EO) effect of PLZT. We demonstrate 5.5-/spl mu/s switching with VOA to obtain the desired output power for optical burst switching (OBS).

Recently, LaGaO/sub 3/ based perovskite material of La/sub 1-x/Sr/sub x/Ga/sub 1-y-z/Mg/sub y/Co/sub z/O/sub 3-(x+y+z)/ (LSGMCO) has been considered as one of promising candidates for an electrolyte of solid oxide fuel cell (SOFC) due to its high oxygen ion conductivity. LSGMCO electrolyte films were deposited on porous anode of Ni and NiO+Ce/sub 0.8/Sm/sub 0.2/O/sub 1.9/ by pulsed laser deposition method. The LSGMCO film deposited at the substrate temperature of 800 /spl deg/C and the oxygen pressure of 20 Pa (72000 laser pulses) had columnar crystallized structures with large boundaries. The LSGMCO film had the high oxygen ion conductivity of 0.7 S/cm at a measurement temperature of 800 /spl deg/C. Open circuit voltage could be measured from our tube type SOFC unit cell utilizing the LSGMCO electrolyte film, however the value was smaller than theoretical one. We found that control of grain size by adjusting the oxygen pressure was needed for the lower temperature operating anode - support SOFC.

This paper tries to realize the backward double salto. This is more difficult and challenging than the backward single salto by a self-standing horizontal bar exercise robot discussed in a previous paper. The present robot has three links that are connected with two rotational joints and driven by two DC motors controlled by a PD-control law. The backward double salto needs 7.3 rad/s over the horizontal bar in the simulation. First, a control method is shown that accelerates rotation around the horizontal bar within two forward giant swings. Finally, experimental results demonstrate a backward double salto which is consistent with the simulated one.

Development of the control and communication system for the plasma heating unit of Large Helical Device (LHD: an experimental machine for fusion science) has been continued. The system is composed of a distributed and concurrent client/server system by the use of several UNIX workstations, and its sub-systems are controlled by PLC (Programmable Logic Controller), VME (Versa Module Europe). Almost all of its control system are connected via Ethernet with IEEE802.3. Man-machine interface system and hardware/software of the control system have been completed.