The present paper outlines the seismic rehabilitation techniques and the seismic energy dissipation devices for preventing existing reinforced concrete buildings from seismic disaster. Also, the purpose of the development of response-control retrofit methods using friction dampers developed by the authors, the mechanism and the effect of its device, and the verification test results are outlined.

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Thermal degradation of EPDM and the effect of antioxidants on the degradation of EPDM was investigated. Using FT-IR (Fourier transform infrared spectrophotometer) micrometer the degree of degradation was analyzed. A new evaluation method of mapping measurement was introduced and showed to be very useful. Among oxidants studied, the phenolic antioxidant 4,4'-tiobis(3-methyl-6-tert.-Butyl phenol was confirmed to be useful. A synergetic effects between phenolic antioxidant 2,2'-methylene- bis (4-methyl-6-tert.buthylphenol) and sulfur type antioxidant, dilauryl thiodipropionate, was also confirmed. The temperature dependence of thermal degradation of EPDM was also analyzed.

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The effect of electrical degradation characteristics and microstructure of Sb₂O₃-added-ZnO varistors were investigated by FE-SEM, energy dispersion X-ray spectroscopy (EDX), optical microscope, X-ray diffraction (XRD), and voltage-current (V-I) characteristics. The nonlinearity index α of V-I characteristic for the Bi-Mn-Co-Sb₂O₃-added ZnO varistors decreased with increasing amount of Sb₂O₃ after the electrical degradation. The twin crystal of ZnO was formed by the addition of Sb₂O₃. The number of twin crystal, of which two c-axes are perpendicular to twin plane, increased and the number of twin crystal, of which two c-axes are parallel to twin plane, decreased with increasing the amount of addition of Sb₂O₃. It is suggested that electrical degradation is affected by combination of orientation of ZnO grains containing twin planes and double Schottky barrier may be not formed in the twin plane.

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Anatase-type TiO₂ thin films for the dye sensitized solar cell are deposited by electrophoresis method. The condition to deposit thin films of high quality is discussed. Ultra fine particles of anatase-type TiO₂ thin film is deposited by the constant current or the constant voltage method. TiO₂ thin films of the high quality without cracks are obtained without binder using the constant current method compared with the constant voltage method. The optimum conditions of electrophoresis for constant current method are the current density I₀ from 0.03 to 0.4 mA/cm² and the deposition time from 20 to 800 s. The film thickness can be controlled by t or I₀ by specifying the concentration of colloidal solution of TiO₂. The quality of TiO₂ thin film increases for the small constant current and the long deposition time. The dye also can be adsorbed on the TiO₂ thin films by electrophoresis method. The values of the open-circuit voltage and the short-circuit current density have increased with decreasing electrophoresis current density and increasing electrophoresis time. It has been found that electrophoresis method for adsorbing dye is effective.

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A pulsed power modulator for the POP experiment of an induction synchrotron has been developed. Various difficulties in the development of the modulator, such as enormous power dissipation at a MOSFET, the resonant ringing in the output waveform, the isolation from the ground potential, and the incorrect action of a gate driving circuit, have been discussed and solved. The developed power modulator is installed into the existing accelerator, KEK 12GeV proton synchrotron. The POP experiment of the induction synchrotron has been successfully conducted. A single RF bunch injected from the 500 MeV booster ring was accelerated to the flat-top energy of 8 GeV.

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In this paper, we propose the estimating method of the magnetic field strength waveforms under the distorted flux density conditions. The estimated magnetic field strength, which is called as EFS, calculated by the magnetic field strength waveform that can be obtained when the specimen is excited with a fundamental sinusoidal frequency component of the distorted flux density waveform. We compare the estimated field strength waveform with the field strength waveform measured under the distorted flux density condition directly, which is called as MFS. Finally, we evaluate the efficiency of EFS.

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Molybdenum silicide (MoSi₂) has high electrical conductivity as much as metal and high chemical stability than SiC in various atmospheres. Therefore, many kinds of MoSi₂ bulk-type heaters are practically used for operation up to 1800°C, which is higher than that of SiC heaters. However, MoSi₂ is fragile at room temperature and has low creep resistance at high-temperatures. The purpose of this study is to fabricate heaters using thin films of MoSi₂, which are deposited on alumina plate-type substrates or crucible-type substrates by RF magnetron sputtering and to evaluate their characteristics. MoSi₂ thin films were deposited on the outside of the alumina crucible, then Pt wires were attached using Pt paste by sintering in vacuum. This MoSi₂ thin film heaters showed linear R-T characteristics and uniform heating state. They also showed good controllability of voltage and stability of power-T characteristics to operate up to 1000°C.

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The decomposition characteristics of hazardous substances such as benzene, toluene, xylene and their mixture in a low pressure DC glow discharge in nitrogen are investigated by mass spectrometry and infrared spectroscopy. It is found that C₂H₂, H₂ and HCN are produced in nitrogen containing benzene, toluene or xylene, and that a trace of CH₄ is also produced in nitrogen containing toluene or xylene. C₂H₂ and HCN are intermediate products, which are decomposed in the discharge, and only H₂ remains in a gas phase. It is likely that C₂H₂ is chiefly produced by the destruction of the aromatic benzene ring of benzene, toluene or xylene and the methyl groups of toluene and xylene slightly contribute to C₂H₂ production. The damping coefficients of the aromatic benzene ring and the methyl group in the glow discharge in the nitrogen containing benzene-toluene or benzene-xylene mixtures are obtained separately.

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In this paper, we describe the basis of a magnetic circuit method and introduce a reluctance network analysis (RNA) proposed by authors. The RNA, which is based on the magnetic circuit method, has some suitable merits for simulating electrical machineries such as a simple analytical model, ease of coupled analysis with electrical circuits, motion, and thermal fields. In addition to these merits, a general-purpose circuit simulator like “SPICE" can be utilized as a solver. We present some applications of the RNA to operation analysis for an orthogonal-core, a switched reluctance motor, and a permanent magnet generator.

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The nanopulse CVD method open the way of DLC deposition at sub-atmospheric pressure. On the other hand, plasma characteristics of nanopulse plasma have not investigated yet. In this paper, we have investigated the plasma characteristics of nanopulse plasma using the Langmuir probe method at low pressure. Using of the characteristics of high electron density created by positive pulse, we have developed the bipolar nanopulse generator consisted with Static Induction Thyristor devices. The deposition rate of this bipolar nanopulse plasma CVD method is five fold higher than that of normal unipolar pulse CVD method. The productivity of plasma assisted coating will be significantly improved by this bipolar nanopulse CVD method.

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Electron transport properties for Lucas-Saelee model in PT and SST conditions are investigated with attention to the effects of ionization. Energy dispersion probabilities through ionization and excitation are compared. A new definition of transverse diffusion coefficient D´_T in steady state with ionization generation of electrons in configuration space is proposed in a form similar to the drift velocity W´_r. Some discussion on the characters of W_r and W´_r proposed by Tagashira and Ikuta are also given.

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In this paper, a theoretical analysis of temperature drift of an eddy current displacement sensor in the case of being applied to copper, and methods for reducing it are described. The change in impedance of the sensor, when the temperature varies, chiefly depends on the change in resistivity of both the wounded wire and the target metal. There recognized little effect of thermal expansion in the prototyped sensor. We analyzed the combinations of one or two sensors, and envelope detection or phase detection. And it was confirmed that the minimum temperature drift could be achieved in the case of two sensors and phase detection.

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The pulsed electroacoustic (PEA) method has been widely used to observe space charge distributions in various solid dielectric materials. The sensitivity of the conventional PEA system is around 1 C/m³. When the charge density is less than 1 C/m³, however, it is difficult to obtain an accurate result because the signal due to the Maxwell stress becomes comparable with the signal to be measured. The Maxwell stress is generated by applying the pulsed electric field to the dielectrics, and independent from the existence of either induced charges by dc bias voltage or internal charges. In order to eliminate the influence of the Maxwell stress, we have developed a new PEA system with a dual polarity pulse generator. The system achieved to measure space charge density around 0.03 C/m³.

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The pulsed electroacoustic (PEA) method has already been widely used to measure the space charge distribution in solid dielectric materials. Since conventional PEA systems can measure the distributions only along the thickness direction, we developed a new system with a capability of doing three-dimensional measurements. However, the system did not have a good lateral resolution. Therefore, in this research, we designed a new nonspherical acoustic lens. As a result, the resolution has been improved both in the thickness direction and the lateral direction.

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The pulsed electro-acoustic (PEA) method has been widely used to observe space charge phenomena in dielectric materials. There have been awaited demands for monitoring space charge phenomena under electron beam or radioactive rays irradiations, or during plasma processing. Therefore we have developed a new PEA space charge measurement system that can observe space charge distributions under such severe conditions. This system uses an open upper electrode that can measure surface and internal space charge profiles at the same time. This paper introduces the 'Open-PEA system' with experimental results obtained during electron irradiation in vacuum.

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In Japan, the recycling ratio of concrete scraps has been kept over 98 % after the Law for the Recycling of Construction Materials was enforced in 2000. In the present, most of concrete scraps were recycled as the Lower Subbase Course Material. On the other hand, it is predicted to be difficult to keep this higher recycling ratio in the near future because concrete scraps increase rapidly and would reach to over 3 times of present situation in 2010. In addition, the demand of concrete scraps as the Lower Subbase Course Material has been decreased. Therefore, new way to reuse concrete scraps must be developed. Concrete scraps normally consist of 70 % of coarse aggregate, 19 % of water and 11 % of cement. To obtain the higher recycling ratio, the higher recycling ratio of coarse aggregate is desired. In this paper, a new method for recycling coarse aggregate from concrete scraps has been developed and demonstrated. The system includes a Marx generator and a point to hemisphere mesh electrode immersed in water. In the demonstration, the test piece of concrete scrap was located between the electrodes and was treated by the pulsed discharge. After discharge treatment of test piece, the recycling coarse aggregates were evaluated under JIS and TS and had enough quality for utilization as the coarse aggregate.

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Simulation for the instability of the discharge oscillation of the Hall thruster has been performed by considering the equation of continuity. It is shown that the ion current becomes stable when the cross-section of the channel is reduced. The improvement of the thrust efficiency is observed by reducing the cross-section of the channel.

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The oscillatory electric field in coaxial cylindrical electrode makes the water high temperature. The hot water formed in the coaxial cylindrical electrode is dependent on the amplitude and the frequency of the voltage applied to the electrode and the size of the electrode.

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Influence of shape of electron arrival-time spectra (ATS) obtained in an electrical shutter drift tube experiment on electron transport coefficients has been investigated. The result shows that the coefficients deduced by the ATS method are not affected by the ATS shape. While it is confirmed that the conventional TOF (Time Of Flight) method gives different values to the coefficients depending on the ATS shape.

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