Power LEDs are convenient tools to study photomorphogenesis in plants. LED modules, such as plant exposure lighting, are easily constructed using power LEDs. Emission spectra of LEDs are narrow bandwidth with peak wavelength. It is possible to isolate the effects of specific photoreceptor systems in plants with these spectra. In order to cultivate plants under the LED light, some LED modules were assembled in laboratory. This paper describes the electric circuits of such LED modules and indoor cultivation experiments. These results indicate that the specific photoreceptor systems exist in plants, since specific spectra of light changes the shape of the plants.

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Characteristic of electromagnetism for a current driven electromagnetic acoustic transducer (EMAT) was estimated using numerical calculation method. High magnetic flux density above 2 T may be achieved by multi-layers piled up the conductors with 50 μm in thickness as a current circuit. This estimated value is much larger than that generated by the EMAT with the permanent magnets. The time variation of the current passing through the conductive layers depends on the characteristic impedance of the pulse forming network circuit. In the case of the larger value of the characteristic impedance compared with that of the internal resistance, the rectangular current was nearly obtained as a function of time. In contract, the current was exponentially decreased for the lower characteristic impedance. However, the time variation of the current supplied by the pulse forming network circuit may affect to only the value of the sound pressure at the detect point of ultrasonic wave.

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Engineering Education is very important from the viewpoint of the technology transfer and the development of the new technology. What methods are expected on Engineering Education regarding to power and energy equipment”? It is useful to apply developed hybrid texts using IEEJ technical papers with special articles that described recent social condition and human experience to educate engineering. This paper describes actual examples of sense and reflection of students under learning Design and Drawing of Electric Equipment in 2010.

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We have observed ground clutter from town and hill using an S-band radar with a frequency of 3.05GHz, a beamwidth of 1.8°, and a pulsewidth of 1.0μs, which is located on the campus of the National Defense Academy in Yokosuka-city. To investigate such ground clutter amplitude statistics, we introduce a compound distribution and the Akaike Information Criterion (AIC). We have found that the ground clutter amplitude obey the compound log-normal distribution with the shape parameters of σ₁=0.424, σ₂=0.232 for entire data and the compound log-normal, and compound log-Weibull distributions with the shape parameters of σ₁=0.217 to 0.429, σ₂=0.028 to 0.410 and c₁=9.36 to 11.20, c₂=17.00 to 23.81, respectively, for data within the beam width of an antenna. The number of the smallest AIC (MAIC) of the compound log-normal, and log-Weibull distributions are 8, and 4, respectively.

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We have investigated a new approach for global earthquake detection based on an experimental fact that microwave signals are generated by rock failures. We already developed an analysis method to detect rock failure microwave signals from the data of a microwave radiometer, the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E) aboard the Aqua satellite, and confirmed that characteristic microwave signals were emitted from the faults and fissures around the epicenter in association with the 2004 Morocco Earthquake. However, at the same time, these results have revealed some problems to be solved before we can move our methodology closer to practical use. In this paper, we review the results obtained in AMSR-E's data analysis phase and summarize the current problems to be solved.

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Recently, FPGA chips are sometimes used instead of fabricating LSI chips in the LSI design education. However the inside of FPGA chip is sometimes regarded as a black box and it is not connected to the knowledge of MOS FET and CMOS gate structures in the field of semiconductor processes. In Graduate School of Engineering, Hiroshima Institute of Technology, we have been teaching “Advanced System Development Technology of Integrated Circuits” as a coursework. Since 2009, we have introduced a prototype chip into the coursework where students draw layouts of half adder, full adder, and 2-bit adder in order to understand the relation between the areas of semiconductor processes and LSI design. The fabricated chip is verified by using logic analyzer. In addition to this, we have introduced an IP database into the coursework, where IP means circuit diagrams or circuits written in hardware description language which are already designed and verified. In order to refer the circuits written in a various descriptions such as VHDL, circuit diagram, etc., we collected those IP, constructed an IP database, and introduced into the coursework. By the questionnaire survey, the effectiveness of both prototype chip and IP database is verified.

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Magnetic Recording heads, the most electrostatic discharge (ESD/EOS) sensitive device of all electric devices, are used for high density magnetic recording applications. Recently, as the devices become increasingly smaller, there has arisen a concern for damaging GMR (Giant Magneto Resistive) heads by EMI. Also, CDM or nano second pulse ESD is key issue for Magnetic head manufacturing. In order to study the effect of ESD (Electro Static Discharge) with nano pulse width for GMR heads, transfer curves of GMR heads using high field QST (Quasi Static Tester) were investigated. By applying ESD damage to GMR head, the transfer curves change the waveforms. Also, there are many kinds of waveforms of transfer curves for after ESD damaged heads. It was found that the degradation of pinned layer was caused by nano pulse ESD and the phenomena were detected by high field QST.

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The number of aged power equipment increases and it is important to clarify the characteristics of deteriorated insulating oil. This paper describes the basic study on molecular behavior in oxidation process of insulating oil by terahertz spectroscopy. The oxidation process of insulating oil was modeled by using various compositions of dodecane and 2-octanol. From the terahertz measurements, the absorption related to hydroxyl groups (-OH) was significantly observed between 6 and 7 THz. The absorption band was also observed in accelerated aging alkylbenzene used in power equipments as insulating oil, and sensitive to hydrogen bonds.

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We have investigated the carbonyl iron powder (CIP) for development of the low-loss power inductor at about 1 MHz. Significant differences were observed for the coercivity between two kinds of CIP (Non-reduction CIP and Reduction CIP). In order to investigate the origin of significant differences for the coercivity, we have studied two kinds of CIP. As a result, it was shown that Non-reduction CIP with low-coercivity is Fe-based nanocrystalline soft magnetic material with high saturation magnetization. We could produce a low-loss dust core using low coercivity CIP at about 1 MHz.

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TiO₂ thin films with a W layer to improve photo-functional properties were prepared by a reactive magnetron sputtering method. The W thin layers with 0.4-2.5 nm in thickness were coated onto the TiO₂ thin film by the same magnetron sputtering. The surface chemical state of the W coated TiO₂ thin films measured by X-ray photoelectron spectroscopy showed W metal or/and W oxide on the TiO₂ thin film. A spectrophotometer was used to investigate UV-Vis absorption of the W coated TiO₂ thin films which absorb energy of longer wavelength than the TiO₂ thin film without the W surface layer. Visible-ray photocatalysis of the W coated TiO₂ thin films was improved by 4 points in the sample with W layer thickness of 1.7 nm and photoconductivity was improved by four times under artificial sun light. It was proved that these improvements of phot-functional properties was achieved by different cause.

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Merging formation of a field-reversed configuration (FRC) was analyzed by using three-dimensional field line traces measured in TS-4 merging experiment. The magnetic field line evolution reveals ‘slingshot’ and ‘overshoot’ motion, which explain relaxation of counterhelicity merging of two spheromaks to an FRC. The sharp bending of magnetic field lines was observed near the X point, suggesting that the Hall effect in process of magnetic reconnection affects the slingshot and the overshoot.

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We proposed a new type of dynamic divertor by use of plasmoid ejection from the main plasma. Our 2-D MHD simulation demonstrated for the first time how the plasmas and coil conditions can control plasmoid dynamics for divertor action. This dynamic divertor has four essential steps. First, current drive and heating causes the main detached plasma to expand around the divertor region, causing a plasmoid formation. Second, the expanding core plasma finally pinches off the plasmoid. Next, the plasmoid isolated from the main plasma is cooled down by Argon gas puff and finally is connected with the divertor plate. The series of divertor actions are expected to reduce the heat road to divertor plate significantly, suggesting a new type divertor useful for heavy heat load from type I Edge-Localized Mode (ELM).

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