The Fundamentals and Materials Society of the Institute of Electrical Engineers of Japan consists of twelve Technical Committees (TC’s) that cover various fields from education to materials. Aiming at introducing significant technological progress made in the year 2003 in the fields relating to each TC, the Editing Planning Committee of the Society asked each TC to write a review. This series of reviews was written in reply to this request by experts in the respective fields.

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There have been accumulated a lot of evidences on seismo-electromagnetic phenomena, and we will show that it is not very impossible for us to make the short-term earthquake prediction by using different electromagnetic phenomena.

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Computational electromagnetics has become an essential tool in modern microwave and lightwave technologies, and many successful numerical methods have been proposed since its birth. In this paper a full-vector finite-element method is introduced to design and modeling of photonic crystal fibers which have attracted much interest recently mainly because of their unique properties.

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Microplasmas with the size of hundreds microns open new world of physics and technology on plasmas. They are formed anywhere you want with the required characteristics and the necessary and sufficient volume. Creation schemes are classified into roughly three modes, namely, concentrated energy mode, space-limited mode, and mass-limited mode. Since the plasmas are in the extremely non-equilibrium state, they will be applied to active plasma devices, new functional material syntheses, micro electro mechanical systems, and ultra-short wavelength light sources.

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The concept of electromagnetic environment and electromagnetic compatibility (EMC) is briefly described. A globalized trend in the 21th century EMC technology is reviewed from the following point of view : EMI (electromagnetic interference) reduction, immunity improvement, human safety evaluation of elecrtomagnetic fields and standardization of EMC measurement.

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For the wide applications of pulsed power technology, highly repetitive pulsed power generators have been recently developed by use of semiconductor switches. Two examples of recent topics will be introduced. One is a combination of an inductive energy storage and semiconductor opening switch. It produces a sharp voltage spike, which is followed by capacitor discharge with long pulse width. It will be used for excimer laser excitation. Another is stacked MOS-FETs, which can be used in the power supply for the accelerators. Various applications of pulsed electromagnetic energy will be expected using highly rep-rated pulsed power generators.

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Three topics of the technical committee on electrical discharges (TC-ED) are summarized for this special issue. First one deals with the modeling of lightning strokes to tall structures. The second one is the advanced technology for nitriding materials and the third is concerned with the environmental problem.

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Optical technology is widely applied in fields such as media, medical treatment, lighting, measurement and lithography. In this paper, topics in the fields of media and lithography are introduced.

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An epoch-making optical sampling oscilloscope has been developed by considering the optical-optical sampling method with low repetition sampling. It becomes possible to measure an optical waveform and evaluate an eye diagram up to 1 THz (1ps). The principle of optical-optical sampling is also described.

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This article reports the state-of-art of DEIS activites. DEIS activiteis are basically based on the activites of 8-10 investigation committees’ under DEIS committee. Recent DEIS activites are categlized into three functions in this article and remarkable activity or trend of each category is mentioned. Those are activities on insulation diagnosis (AI application and asset management), activities on new insulation technology for power tansmission (high Tc super conducting cable insulation and all solid sinulated substation), and activities on new insulating materials (Nanocomposite).

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From the IT field abd the PT field, advanced and highly specialized materials are increasingly required. Especially, specialized requirements for metals and ceramics should be spreaded these characteristics on the basis of new materials and nanotechnology. In this paper, some advanced metals and ceramics regarding to generation changes in process materials, new dielectrics for the digital devices field, compound semiconductors for the power devices field, and materials for the optoelectronics field will be reviewed and forecasted.

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The recent magnetics research and development including micromachine, magnetic meterial and biomagnetics fields has come to the new deveropment stage. The representative studies are outlined from these fields. First, Micro dc motor is mentioned as an example of the machine application. Next, miniaturized DC-DC converter using the magnetic thin film inductor are explained. Finally, the magnetic field effect to the organism is introduced.

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Japanese technologies showed significant advances in the decade of 1980s. Focusing on that period, one project has been started to record and internationally publicize those technologies. The National Institute of Informatics has become a core organization with the cooperation of the five electricity related Japanese societies. The five are the Institute of Image Information and Television Engineers, the Information Processing Society of Japan, the Illuminating Engineering Institute of Japan, the Institute of Electrical Engineers of Japan, and the Institute of Electronics, Information and Communication Engineers.

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Weibull-distributed clutter are reviewed. Most of the clutter received by L, S, X and Ku band radars obeys a Weibull distribution when reflectors are terrain, sea, sea-ice and rain clouds. Clutter suppression techniques for Weibull clutter are also reviewed. Especially, Weibull CFAR is emphasized.

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We have developed a computer code for the simulation of large scale SWP plasma excited by a long coaxial antenna with a VHF wave of 300 MHz, this antenna is located along the center axis of a cylindrical chamber. The antenna used in this model structure is so long that the computational region has become very large. Therefore, for the calculation of the electromagnetic field profile in order to design a long and large scale SWP plasma, it is necessary to apply a proper boundary condition to truncate the computational region, and from this viewpoint we have introduced the PML absorbing boundary conditions and have studied the effectiveness of this boundary conditions for our purposes.

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The Moving Target Indicator (MTI) is usually utilized in order to detect the moving targets embedded in ground clutter. Coherent Doppler radar is used for the typical MTI. As an alternative, we investigate an area MTI using a non-Doppler radar. The area MTI is defined as scan-to-scan cancellation, that is, the observed area is subtracted from scan to scan. This time, we observed an aircraft embedded in ground clutter at Niigata airport by using an X-band non-Doppler radar. It is shown that the amplitude statistics after scan-to-scan cancellation obey a Weibull distribution. To suppress such ground clutter, we apply a noble Constant False Alarm Rate (CFAR) method. An improvement value of target-to-clutter ratio 18.95dB was obtained.

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Surface modification has been carried out of graphite targets irradiated by intense pulsed ion beam. The highly oriented pyrolytic graphite ( HOPG ) targets were irradiated by 70 - 120 J/cm² of pulsed ion beams. To evaluate temperature on the irradiated surface, the deposited energy was measured by using the thermistors attached on the back of the targets. The fast heating and fast quenching occurred on the target surface, which were enhanced at the higher energy density of beam irradiation. On the irradiated surfaces, sphere particles and whiskers were found by scanning electron microscope observations. By Raman spectroscopy, structural changes were confirmed on the irradiated surfaces and the intensity ratio of a peak at 1360 cm^-1 to that at 1580 cm^-1 was increased with increasing the ion beam energy density.

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We have developed optical frequency standards for wavelength-division-multiplexing (WDM) optical communication systems based on absorption lines of acetylene molecules in the 1.5 μm region. We developed acetylene-stabilized diode lasers using a Doppler-free saturation absorption of acetylene as a frequency reference. We also developed an accurate frequency measurement sysytem in the 1.5 μm region and the absolute optical frequency of an acetylene line was measured with an uncertainty of 12 kHz. As a result, the acetylene optical frequency standard can be used as an accurate absolute frequency reference for the calibration of optical instruments used in the WDM systems.

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An acousto-optic laser deflector was applied to laser interferometric measurement of impulse discharges in air as a high-speed shutter. Laser interference fringes were obtained at exposure times of about 1 μs. The deflector was also used for time-resolved imaging of laser interference fringes by using a sequence of high frequency signals with different frequencies to deflect the laser beam to different angles at different times, allowing multiple interference images to be captured on a single video frame. Changes in laser interference fringes due to an impulse discharge in air showed electron densities of about 2x10²⁴ m^-3 and perturbation in the neutral density expanding at speeds of about 10³ m/s.

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A merging formation of field-reversed configuration (FRC) has been studied for the first time without central conductor, using two merging spheromaks with opposing toroidal magnetic field. Without the n=1 stabilization effect of the central conductor, the merging process was maintained stably probably due to (1) plasma flow shear generated by the counterhelicity reconnection and (2) line-tying effect of the magnetic field lines. This relaxation from the force-free (≈0.05-0.1) spheromaks to the high-beta (≈0.7-1) FRC is attributed to efficient (≈80%) conversion of the toroidal magnetic energy of the former to the ion thermal energy of the latter. This energy conversion was caused by a direct ion heating and acceleration effect of reconnection under the toroidally symmetric condition. This ion heating energy was found to increase inversely with the field amplitude parallel to the X-point line. Further plasma acceleration by high-field compression was observed to increase the reconnection speed, revealing the new fast reconnection mechanism called the current sheet ejection.

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The propagation of lightning electromagnetic radiation over a lossy ground has been investigated numerically with the combined use of a newly developed computer algorithm for Sommerfeld integrals and the fast numerical inverse Laplace transform. The transmission line model has been adopted as the lightning current model and we have dealt with lightning discharges with sharp initial peak. The dependences of the radiation fields (especially horizontal electric field) on ground conductivity, distance etc. have been extensively studied, with a special reference to its comparison with previous approximations by Zenneck and Cooray and Rubinstein. Based on these comparisons, we have found that our numerical methods are effective when calculating the radiation field from the lightning for any combinations of the parameters including ground conductivity, distance etc.

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We review the new findings on natural electromagnetic phenomena in the near-Earth environment and will show the importance of electromagnetic analyses in elucidating the essential points of these phenomena. The topics include (1) atmospheric phenomena related to lightning (e.g. mesospheric optical emissions); (2) seismo-electromagnetic phenomena (electromagnetic phenomena associated with earthquakes and/or volcano eruptions); (3) plasma and wave phenomena in the Earth’s ionosphere and magnetosphere; and (4) electromagnetic or electrodynamic coupling among different regions. We pay our greatest attention to the unsolved essential problems for each subject, and suggest how electromagnetics would contribute to a solution to those problems.

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Early phase of powder plasmas powered by a pulsed high current discharge was examined by use of high-speed cameras and a laser shadowgraph and schlieren techniques. Initial electrons created by a pre-ionization discharge collide with both an anode and powder particles, of which surfaces evaporate after then. Evaporation of the particle by electron collision initially occured in the hemisphere surface which is close to cathode side. Since vaporization of the anode far exceeds that of the particles, discharge characteristics is almost similar to that of vacuum sparks in which expanding anode plasmas are observed. In order to suppress the developpment of the anode plasma, reduction of the effective anode area by varying the anode shape was examined.

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In heavy ion beam (HIB) inertial confinement fusion (ICF), key issues include an accelerator design for an intense HIB, an efficient HIB transport, interaction between HIB and reactor gas, a HIB-target interaction, a reactor design and so on. In this paper, three-dimensional computer simulations are performed for a HIB irradiation onto a direct-driven spherical fuel pellet in HIB ICF in order to clarify the dependence of multi-HIB illumination non-uniformity on parameter values of HIB illumination. We investigate the energy deposition non-uniformity using 12, 20, 32, 60, 92 and 120-beam irradiation systems. In this study, effects of HIB temperature and emittance are also evaluated. The calculation results demonstrate that we can realize a sufficiently low non-uniform energy deposition, for example, less than 2[%] even for a 32-beam irradiation system using the Gaussian beam.

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To develop a common-mode noise filter for balanced-mode digital signal interfaces such as USB ver. 2 and IEEE 1394, a Mn-Zn ferrite/Polyimide composite thick film was fabricated and applied to the filter device. The polycrystalline Mn-Zn ferrite powder and polyimide precursor liquid solution were used as the starting materials for the composite thick film. The composite film had a large imaginary part of complex permeability at high frequencies over 1GHz, and high permittivity. The common-mode noise filter using the composite film exhibited the common-mode suppression of over 10dB in the frequency range over 1GHz.

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Ultraviolet photons were irradiated to the surface of all-aromatic polyimide films using a KrF excimer laser or a KrCl excimer lamp, and electrical properties such as permittivity, dielectric loss factor, conductivity, and space charge distribution were measured. In the case of the intense laser irradiation, the photo-induced change is drastic. The irradiated side of the sample is carbonized and becomes conductive. The apparent thickness of the remaining insulating region estimated by the space charge distribution measurements agrees with that observed by an optical microscope. The permittivity of the remaining apparently insulating region decreases as the irradiation proceeds, which is due to a decrease in the number of carbonyl groups. The dielectric loss factor and conductivity in this region increase since the leakage current increases even in this apparently insulating region. The activation energy of conduction also increases. In the case of the weak lamp irradiation, the permittivity decreases and the conductivity increases, although clear surface change is hardly observable. It is indicated from space charge distribution measurements that carrier traps are formed by the irradiation.

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Polyimide films have been commonly used in industries such as for an insulating material of a printed circuit board. We measured space charge profiles of a polyimide film under dc electric filed, and reported that charges were injected into the film under a dc electric field of 10 kV/mm. However, vaiours types of polyimide films have been developed with different types of monomers. In this study, we observed space charge behaviour of two types of polyimide films and found that charge injection appeared only in one type.

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