Ground Penetrating Radar (GPR) has been widely used applications which include detection of subsurface facilities, concrete inspection and archaeology. Among these applications, humanitarian demining is still difficult task. Since 2002, we have developed a new hand-held land mine detection dual-sensor ALIS. ALIS is equipped with a metal detector and a GPR, and it has a sensor tracking system, which can record the GPR and Metal detector signal with its location. ALIS can process the data and is used for image re-construction by migration processing. ALIS is the only one mine detection system in the world which can visualize the GPR image by hand scanning. We found that the migration processing can reduce the clutter and gives us clear images of buried mines. After several tests of ALIS in mine affected courtiers, operation of ALIS in mine fields in Cambodia started in summer 2009. Two sets of ALIS have been operated in Cambodia and more than 77 antipersonnel mines have been detected and 137,000m² farmland was cleaned.

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Recent researches on plasma-liquid interface are introduced. One is about plasma-water interaction at the interface of pulsed dielectric-barrier plasma in gas-liquid two-phase flow for water treatment. Acetic acid in water is decomposed as a persistent material. Numerical calculation indicates that plasma-water interaction which is O-radical-induced generation of liquid-phase-OH radical occurs. The other reports highly-concentrated adsorption of a surfactant at plasma-water interface, and an interfacial reaction decomposing the surfactant. Perfluorooctane sulfonic acid is an extremely persistent surfactant, but can be decomposed by plasma attached to the solution. The decomposing reaction occurs at the plasma-water interface. Estimation of the amount of PFOS adsorbing to the plasma-water interface shows much higher mole fraction of PFOS than that in bulk water. Thus, the plasma can effectively react with PFOS at the water surface and exhibits high energy efficiency.

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Cryptographic modules are now mounted on many commercial products for secure transactions and communications. On the other hand, a new class of physical attacks against cryptographic modules, which is called “side channel attack,” is drawing much attention due to the non-invasive nature and effectiveness. This paper presents an overview of the research trends in side-channel attack and the related activities to counteract such attacks and evaluate the security of cryptographic modules.

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The KEK digital accelerator is a small-scale induction synchrotron, which potentially accelerates any species of ion, regardless of possible charge state. This paper describes the progress status of its beam commissioning and the novel switching power device that bring in the dramatic improvement in the digital accelerator.

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The technical committee on light application and visual science (TC-LAV) has been surveying fields of application of optical engineering and visual science, covering medical science, devices for visual information processing, light sources from terahertz wave to extreme ultraviolet, advanced lithography, and so on. This article introduces two topics from recent research activities. They are optical control of thick resist pattern profiles, and characteristics of random errors in intensity and phase measured with THz time-domain spectroscopy.

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Instrumentation and measurement play a vital role in research and development in the science and engineering fields. Recently, the goals of instrumentation and measurement have expanded to meet not only the industrial and science requirements but also the needs in all fields of social life, such as medicine and welfare, the environment, and disaster and security.
In this article, recent technical topics in the instrumentation and measurement field are reported.

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Thermoelectric technology for effective use of unutilized thermal energy is expected. Thermoelectric generating system composed of the thermoelectric module can convert thermal energy into direct electric energy. This paper focuses on technologies to thermoelectric materials, module and system.

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The activities in permanent magnet committee in the institute of electrical engineers of Japan from April, 2008 to March, 2010 were summarized and reported. The main topics are; (1) rare-earth elements resource problem, (2) research activities in Japan, (3) applications of permanent magnets, (4) some technical and research topics, and (5) overview of a basic problem in Nd-Fe-B magnets; the grain boundary properties.

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The electric technology had contributed to the human life in 20^th century, Now it is time to reward important contributions to this innovation, such as Persons, Materials, Locations, etc.. Such kind of award enshrines the hidden stories of electric technology to the public. IEEJ has responsibility to carry out these activities.

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When measuring multicarrier communication system such as Orthogonal Frequency Division Multiplexing (OFDM) or UWB wireless signal, there is a problem that the effective measuring dynamic range of the measuring instrument may be reduced since the Peak to Average Power Ratio (PAPR) of the measured signal is significantly high. In order to solve this problem, we propose a technique that maintains the measuring dynamic range by dividing measured signal into plural bandwidths to decrease the measured signal power. We made a prototype of the measuring equipment, confirmed the operation of the algorithm, and verified the effectiveness of dynamic range improvement is 5 to 8 dB in relation to conventional circuit.

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Analysis of lightning electromagnetic field using the FDTD method have been studied in recent year. However, large-scale three-dimensional analysis on real environment have not been considered, because the FDTD method has huge computational cost on large-scale analysis. So we have proposed a three-dimensional moving window FDTD (MW-FDTD) method with parallel computation. Our method use few computational cost than the conventional FDTD method and the original MW-FDTD method. In this paper, we have studied about computation performance of MW-FDTD parallel computation and large-scale three-dimensional analysis of lightning electromagnetic field on a real terrain model using our MW-FDTD with parallel computation.

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The International Electrotechnical Commission (IEC) prescribes in IEC 61000-4-2 immunity tests of electronic equipment against electrostatic discharge (ESDs), in which indirect discharges of an ESD gun onto a vertical coupling plane (VCP) in the vicinity of equipment under test (EUT) are specified for simulating human discharges to conductive materials being adjacent to the EUT. According to IEC 61000-4-2 2008-04, the VCP shall be placed at a distance of 0.1m from EUT to be tested, and the indirect discharges of an ESD gun should be conducted to the centre of a vertical edge of the VCP, though the reference arrangement of EUT is not specifically determined. In the previous study, we measured electromagnetic fields due to indirect discharges of an ESD gun onto a VCP to investigate their variations with respect to EUT positions, which showed that indirect discharges onto a vertical edge from the back side of a VCP are very likely to reduce the above-mentioned variations, while the induced voltage levels become low. In the present study, to cope with this problem, we proposed a tapered-type VCP in lieu of the IEC-specified VCP, and by using a magnetic field probe in place of EUT, we measured its induced voltages of a magnetic field probe for indirect discharges of an ESD gun onto the VCP, and examined the variations in peaks and waveform energy with respect to the probe positions. As a result, we found that the tapered-type VCP suppresses the variations in peaks by 71% and waveform energy by 40% compared to the IEC-specified VCP. To further validate the above findings, as an actual EUT, we used a commercially available ESD detector for an impulsive electric field to reveal that the tapered-type VCP provides 16%-reduced variations in its detection rates with respect to the detector positions in comparison with the present VCP.

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In store lighting, difference in the look-and-feel of foods gives effects on the purchasing power of customers. This study conducted the digitalization and quantification on the effects of the variation of light-source color and illuminance used for lighting foods on image recognition on foods. As a result, it was clarified that when meat was illuminated with the light source of “pink” or “faint pink,” image evaluation on foods became higher. In addition, when illuminance increase was applied to these two light-source colors, image evaluation on “faint pink” became further higher. The reason is supposed to be that the redness of meat increased, which may have enhanced fresher impression. From this study, it has been clarified that the light-source color and illuminance optimum for each food are variant. The results show that lighting foods with the optimum light-source color and illuminance can make foods look better.

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It is one of our dreams to mechanically recover the lost body for damaged humans. Realistic humanoid robots composed of such machines require muscle motion actuators controlled by all pulling actions. Particularly, antagonistic pairs of bi-articular muscles are very important in animal's motions. A system of actuators is proposed using the electromagnetic force of the solenoids with the abilities of the stroke length over 10 cm and the strength about 20 N, which are needed to move the real human arm. The devised actuators are based on developments of recent modern electro-magnetic materials, where old time materials can not give such possibility. Composite actuators are controlled by a high ability computer and software making genuine motions.

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Effect of electrolytes on the decolorization of indigo carmine and on the production of H₂O₂ by pulsed discharge in air spraying water droplets was performed in sodium chloride and magnesium sulfate solutions. Peak voltage of the discharge decreased with increasing solution conductivity, but peak current and discharge energy increased. Decolorization rate and decolorization efficiency of indigo carmine and the yield of H₂O₂ decreased with increasing chloride and sulfate ion concentrations. It was found that the decolorization of indigo carmine and the production of H₂O₂ are affected by the ion concentration even in the case of discharge in air spraying water droplets. However it was less effective than that of discharge in water. Chloride ion was more effective than sulfate ion regarding the decrease of decolorization rate and the production of H₂O₂. Decolorization rate of indigo carmine was strongly related to the production of H₂O₂. These results also indicated that decolorization of indigo carmine depends on the production of hydroxyl radical.

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Recently, electric power equipments insulated by epoxy resins have been accident-filled, so that we have been interested in the degradation character of epoxy resin insulations at normal temperature to estimate their life. Thus the aging tests on epoxy insulations were accomplished, and then resistive leakage current on their insulations kept in a glass state at 90 and 80°C was measured by the method canceling capacitive current which was applied to degradation estimation of ZnO varistors. Results of reduced resistive leakage current were led to evaporation and migration of hydrogen ions in epoxy insulations, which are compared between new ones and used ones and applied to estimation of aging degradation in this paper.

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Volume resistivities of polyimide film under simulated space environment are measured with “charge storage decay method.” The test material was irradiated by electron beam in a vacuum chamber to simulate space environment. Volume resistivity is calculated from the surface potential decay time constant after stopping electron irradiation. This is called “charge storage decay method” and is shown to be the preferred method to determine resistivities of highly insulating materials. As a result of experiments, we have found that volume resistivity of polyimide film is in order of 10¹⁶ Ωm, which is one order higher than the result from the conventional resistivity measurement method prescribed in JIS or ASTM. Higher resistivity requires much longer field relaxation time after injection of electron to dissipate through the material. Thus, charging analysis of spacecraft needs to consider this higher resistivity. The effect of injection energy of electron is also examined and it is found that the higher the energy is, the faster the charge decay become.

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The measurement system of the surface electrostatic potential on a solid insulation board in vacuum has been developed. We used this system to measure the electrostatic potential distribution of the surface of a borosilicate glass plate applied a high voltage. A local increase in the electric field was observed. It is considered that this phenomenon is caused by a positive electrostatic charge generated by a secondary emission of field emission electrons from an electrode. On the other hand, a local increase in the electric field was not observed on a glass plate coated with silica particles and a glass plate roughened by sandblast. We reasoned that this could be because the electrons were trapped by the roughness of the surface. It is considered that these phenomena make many types of equipment using the vacuum insulation more reliable.

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Neodymium-iron-boron (Nd-Fe-B) magnets exhibit exceedingly high maximum energy products and remanences. Their coercivities, however, decrease rapidly with increasing the temperature, and the magnets are easily demagnetized at elevated temperatures. To reduce the effects of temperature, the coercivity at the room temperature is enhanced by the addition of the dysprosium (Dy), which causes a reduction in remanence. The Grain Boundary Diffusion process is a technology to enhance coercivities while suppressing a large reduction in remanences. Dy that is effective for the coercivity enhancement is supplied from the magnet surface and diffused into the magnets through the grain boundary phase, and then put at the grain surface. When the Grain Boundary Diffusion process is applied to relatively large magnets, the partial coercivities near the magnet surface, where higher coercivities are generally required, can be enhanced effectively. In other words, the magnets exhibit nonuniform coercivity. We have conceived a simple and effective method for estimating the demagnetization curves of such nonuniform coercivity magnets. In this paper, the validity of the estimation method was examined.

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