Properties of laser-produced plasmas (LPP) are described to generate intense radiation for various applications including extreme ultra-violet (EUV) light for next generation lithography. After an overview of LPP physics, state-of-the-art topics relevant to the 13.5 nm EUV source are described

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Recently, an information technology is indispensable for the business and industrial developments. However, it has been a social problem that the number of software developers has been insufficient. To solve the problem, it is necessary to develop and implement the environment for learning the algorithm and programming language. In the paper, we will describe the algorithm study support system for a programmer using the flowchart. Since the proposed system uses Graphical User Interface(GUI), it will become easy for a programmer to understand the algorithm in programs.

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In recent years, the demand for plasma display panels has expanded rapidly with the start of high definition digital broadcasting. However, the luminous efficiency of plasma display panels is still low compared with cathode-ray tube displays. With respect to the market expansion, further improvement of the efficiency is required. In the present work, we proposed a new driving scheme applying radio frequency voltage to coplanar electrodes and simulated the discharge behavior in a plasma display cell using a two dimensional fluid model. As a result, the discharge evolution in the cell was clarified at addressing and sustaining periods. The radiation efficiency of ultraviolet light was about 4 times as large as that of a conventional plasma display panel. The barrier rib height was a considerable parameter because of the significant influence on firing and sustaining conditions.

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This paper describes experimental results of NO removal from a simulated exhausted gas using a barrier-type plasma reactor subjected to reciprocal traveling wave voltage pulses. A pulse-forming cable was charged and then grounded at one end without any resistance, so that a traveling wave reciprocated along the cable with a change in its polarity because the traveling wave was negatively reflected at the grounded-end. Transient discharge light between point-plane electrodes with a glass barrier was observed using a gated image-intensifier. Photographs of the transient discharge light indicated that many streamer channels extended widely in the gap at the initial stage in the voltage oscillation, while only an intense discharge channel was observed at the latter stage. NO removal tests were carried out using the reciprocal pulse generator and a coaxial plasma reactor with a cylindrical glass-barrier. Results indicated that the discharges at the first and the second polarity reversals contributed largely to the oxidation reaction from NO into NO₂, whereas the contribution of the subsequent discharges in the latter stage to NO removal was small.

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Neutral density variations accompanying progression of streamers, which occur upon application of lightning impulse to an air gap, were observed using laser interferometry. The optical emission accompanying streamer progression was monitored simultaneously. In the case of positive polarity, the spatial distribution of neutral density variations and optical emission showed high correlation. In the case of negative polarity, the correlation was substantially lower, and neutral density variations were often observed when optical emission from the corresponding region was absent. The results showed that the corrlelation between the spatial distributions of neutral density variations and of optical emission differs largely according to the polarity.

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Four Zener voltage standards ( Fluke 732B ) belonging to National Metrology Institute of Japan (NMIJ), AIST have contained in a particularly designed box that is called an “up-graded box". This box need for enhancing the insulation resistance occurred between the 1.018 V output terminal and chassis of the Zener voltage standard, because the 1.018 V output voltages have 1kΩ output-resistance. Hence, affect refer to best measurement capability 4 nV (k=1) of the 1.018 V output voltage arises from load effect between the insulation resistance and 1kΩ output-resistance. Moreover, this insulation resistance has an effect on the environmental humidity-change of 40%RH, 50%RH, 60%RH, 65%RH and 70%RH. Therefore, this paper revealed type B standard uncertainty of the 1.018 V output voltages arose by the humidity characteristic of the insulation resistance.

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Whereas high resolution digital recorders are used in recording the impulse voltage tests in prominent accreditation laboratories worldwide, a usage of an 8 bit recorder is also allowed by IEC publication. An 8 bit recorder is, due to its nature, known to record a waveform with 0.4% vertical resolution and it has not been appreciated for determining a peak value of lightning impulse in the reference measuring system where the scale factor is often evaluated with 0.1% or less uncertainty. This paper demonstrates simulation in which an 8 bit record with an internal noise is fed into the lightning impulse parameter determination software and the computed parameters were compared with theoretical values. The results show that, if suitable software is used, errors in parameters deduced from an 8 bit record is as small as those derived from a 12 bit record, suggesting an inexpensive 8 bit recorder can replace a 12 bit in impulse voltage measurements.

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Earthquake- related electromagnetic phenomena are recently considered as a promising candidate for short-term earthquake prediction. There have been accumulated a lot of evidences of precursory signatures in a wide frequency range (DC-VHF), but the ULF geomagnetic change is one of the most promising phenomena. We review our latest results on seismogenic ULF emissions; characteristics of those emissions and methodologies to detect abnormal changes in ULF electromagnetic field associated with earthquakes.

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The dynamics of the micro magnetic switch driven by optical heating is simulated. By using Three Dimensional Finite Difference Time Domain (FDTD) program newly developed and FEM, a small armature composed by thermo-sensitive magnetic film can operate faster than 0.05ms by heating power of 7mW or less, Bi-stable operation is also confirmed.

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Melt-spun ribbons of Pr-Fe-Co-Nb-Cu-Si-B system alloys were prepared by single roller rapid-quenching method. Effects of composition,wheel velocity and heat-treatment on magnetic properties were investigated. The optimum preparation conditions of compounds were as follows: composition Pr₉Fe_68.5Co₁₀Nb₁Cu_0.5Si_0.5B_10.5; wheel velocity 12.5 m/s; heat-treatment 625 °C for 5 min. Magnetic properties obtained were (BH)_max = 121.8 kJ/m³, J_r = 0.90 T, H_cJ = 898.7 kA/m, and H_cB = 509.0 kA/m. Temperature coefficients of J_r and H_cJ of the ribbons of Pr₉Fe_68.5Co₁₀Nb₁Cu_0.5Si_0.5B_10.5 alloy were α(J_r)_ave = -0.034 %/°C and α(H_cJ) = -0.290 %/°C, respectively. The value of (BH)_max for the isotropic Pr₉Fe_68.5Co₁₀Nb₁Cu_0.5Si_0.5B_10.5 bonded magnet prepared by using ribbons annealed at 625 °C for 5 min is 84.4 kJ/m³. Irreversible loss of the bonded magnet is -2.74 % (at 125°C).

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The establishment of the nondestructive inspection technology with plant structures has been stimulated by the recent occurrence of cracks in the nuclear power plant structures. In this research, a uniform eddy current multi-probe to apply to the complex structure and inspect the cracks at high-speed data acquisition was developed. Pick-up coils of the developed probe were arranged on a flexible printed circuit board. This probe was able to obtain clear signal for an EDM (electro-discharge machining) slit with 0.5 mm depth and distinguish EDM slits arranged at 2 mm intervals. It was confirmed that the SCC (stress corrosion cracking) of real flaw was able to be detected with developed uniform eddy current multi-probe by using the ferrite core for the exciting coil and considering the impedance matching of the exciting coil and the flaw detection device.

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