Recently, two-dimensional vector magnetic measurements have become popular and many researchers have been trying to develop a more accurate measuring system and a standard measurement device. In development of high-efficiency actuators, use of high magnetic flux density designs can assist high torque, weight reduction and size down. It is therefore very important to understand the magnetic properties under high magnetic flux conditions in the electric steel sheets. However, there are still some difficulties in the measurements, due to nonlinearity and anisotropy of magnetic materials. The measured magnetic power losses of the clockwise and counter-clockwise rotating fields become different for magnetic flux density over 1.2 T and the value in counter-clockwise case sometimes became negative. It can be considered that angle errors of H and B-coils are the main reasons of the measurement errors. In this paper, the angle errors of the double B-coil (search coils) and the double H-coil (cross-type H-coil) are evaluated with a calibration device, which consists of a special solenoid coil and a high-precision turntable. The magnetic properties are compensated with the measured angle errors.

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Influence of streamer-to-glow transition in NOx removal from a simulated diesel exhaust gas using pulse streamer discharge (PSD) reactor is described in this paper. A co-axial cylinder type discharge chamber was used as the PSD reactor which was driven by inductive energy storage (IES) pulse power generator with semiconductor opening switch (SOS). The pulsed power generator supplies both polarity of 30 kV pulse with 300 pps repetition rate and 25 ns pulse width. The co-axial cylinder plasma reactor consists of 1 mm diameter tungsten wire and 19 mm i.d. copper tube with 30 cm length. NO removal from the simulated gas (N₂:O₂=9:1, Initial NO concentration=200 ppm) increased with input energy into plasma reactor. The energy efficiency for NO removal was obtained to be 25 g/kWh at 30 % removal in gas flow rate of 2 L/min. However, the energy efficiency decreased to 4.6 g/kWh with increasing capacitance of the primary capacitor from several hundreds pF to several nF. This decrease is caused with streamer-to-glow transition.

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This paper describes an application of the equivalent multipole moment method (EMMM) with polar translations to calculation of magnetic fields induced by a current dipole placed in a human head model. Although the EMMM is a conventional Laplacian field solver based on spherical harmonic functions, the polar translations enable it to treat eccentric and exclusive spheres in arbitrary arrangements. The head model is composed of seven spheres corresponding to skin, two eyeballs, skull, cerebral spinal fluid, grey matter, and white matter. The validity of the calculated magnetic fields and the magnetic flux linkages with a loop coil locating nearby the model is successfully confirmed by the reciprocity theorem derived by Eaton.

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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. When studying the basic computer programming, the Lego MindStorms Robotics Invention System(RIS) may be promising. It is possible to use the graphical user interface (GUI) based programming environment with RIS. However, one can't adopt it readily because of its higher price for students. Therefore, we have developed the control system of the virtual intellectual education toy control system where one can experience the preliminary study of programming language easily.

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The polarization angle rotation of the propagating beam was estimated in a partially ionized atmosphere under discharge conditions. The polarization plane angle rotation is caused by the magneto-optical effect; Faraday effect. The estimated rotation angle is of the order of < 1 degree, but can be detected with an extinction ratio of polarization of >30dB. We examined the effects of the optical path length of repeating square mirror optics and an air-gap length of the discharge on the rotation angle.

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Since the gas discharge plasma easily converts NO to NO₂, which can be reduced more actively in selective catalytic reduction with hydrocarbons (HC-SCR), the plasma-assisted HC-SCR is an effective method for NOx reduction from diesel engine exhaust gases. In this work, the relation between NOx removal and reaction products is investigated in plasma-assisted HC-SCR in simulated flue gas as parameters of gas composition, plasma specific energy and catalyst temperature. C₂H₄ is used as a hydrocarbon and commercially available Al₂O₃ is used as a catalyst. After the plasma treatment of simulated flue gas, HCHO and HCOOH were generated as by-products, while NO was effectively converted to NO₂. These by-products were confirmed to be reactive at lower catalyst temperature than C₂H₄ in HC-SCR. The relation between NOx removal and reaction products suggests that HCHO and HCOOH contribute the effective NOx reduction at low catalyst temperature in plasma-assisted HC-SCR.

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An attosecond high-density electron bunch is produced by an intense short-pulse TEM₁₀+TEM₀₁-mode laser. The transverse ponderomotive force of the TEM₁₀+TEM₀₁-mode laser confines pre-accelerated electrons in the transverse direction, and at the same time the laser longitudinal electric field accelerates the electrons. Our three-dimensional particle simulations show that the pre-accelerated electrons are accelerated to a few hundreds MeV and are compressed to ∼499 attoseconds with a low energy spread (∼±3.5 %). The electron density of the attosecond bunch reaches ∼43 times as high as the initial number density. Such the attosecond electron bunch is now available to attophysics.

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Development of energy and environment education learning unit for upper grade of elementary school is described in this paper. A regional collaboration among elementary schools, universities and municipal governments was utilized to develop the learning unit effectively. The learning unit was proposed based on the analysis using questionnaires done to the sixth grade students in Yahaba-Higashi elementary school. The results of the analysis revel that the 78% students acquire the knowledge about energy and environment by the previous times of synthetic learning. However, the students do not have strong motivation to act for remediation of the energy and environmental circumstances, whereas they have rich-knowledge about those issues. Based on the analysis, the learning unit of energy and environment was designed with focusing to get the skill through the demonstrational experiment developed and/or arranged by academic staffs in Iwate University and in Yahaba-Higashi elementary school. The designed learning program was carried out as time of synthetic learning and was evaluated by questionnaires. The results showed the designed energy and environment learning program motivated to act locally for sustainable development.

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To study the space charge generation in cross-linked polyethylene (XLPE) and ethylene propylene copolymer (EPR), space charge profiles in both materials are measured using PEA method. The experimental results demonstrated that a big difference was discovered in the detected charge profiles between XLPE and EPR. We discovered that the diffusion of charge is significantly faster in EPR than in XLPE. The authors confirmed that the negative hetero-charge is generated near the positive electrode in EPR when moisture are coexisting with acetophenone. The effects of antioxidants on the generation of hetero-space charges in XLPE and EPR are also studied using XLPE and EPR samples containing different kinds of phenolic and sulfur type antioxidant. The authors discovered that hetero-charge is generated in XLPE and EPR containing sulfur type, or sulfur-containing phenolic, antioxidant when acetophenone are existing in the material. The hetero-charge generation is inferred to be caused by the combined effect between acetophenone and the component containing sulfur atoms of the antioxidants.

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An antistatic agent is often used for avoiding electrification of polymer films. In some cases, the film has a double-layer structure to improve its adhesive property. As an example, an ethylene-vinylacetate copolymer (EVA) film in which an antistatic agent is mixed, corresponding to “EVA(ASA)”, is laminated with a low-density polyethylene (LDPE) film. In such a case, there is a possibility that the antistatic property of the EVA may be lost because of the diffusion of the antistatic agent into the LDPE side.
A space charge study on the EVA(ASA)/LDPE laminate was carried out using the pulsed electroacoustic method under DC voltage. The space charge once formed at EVA(ASA)/LDPE interface decreased with time, and propagated into LDPE. A space charge profile at EVA (ASA)/LDPE interface was also calculated with difference of conductivities between LDPE and EVA(ASA). The space charge profile at EVA(ASA)/LDPE interface was qualitatively corresponded to that from space charge measurement. As a result, it was suggested that diffusion of the antistatic agent led to this space charge behavior. It was considered that measurements of space charge profiles would enable the assessment of diffusion of antistatic agent in multi-layer.

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Life-cycle management combined with degradation diagnosis is useful for preventing an unexpected failure and extending service life of electric power apparatuses, minimizing life-cycle cost. We examined a method of life-cycle management based on TBM (Time-Based Maintenance) and CBM (Condition Based Maintenance), and evaluated the economic effect of degradation diagnosis. To carry out reliable life cycle management, however, accurate data on the relation between extent of degradation and failure probability or remaining life as well as a well-established diagnostic method are necessary. In this paper, we examine the influence of accuracy of the data used to determine the optimum diagnostic parameters and evaluate how the life-cycle cost is affected by the employment of inaccurate data. As more condition-oriented life-cycle management, we discuss the effects of a method of life-cycle management based on two diagnosis intervals in terms of reliable life-cycle management. We also discuss the measurement sensitivity necessary for an effective asset management based on diagnosis.

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The O-rings have been usually applied to mechanically moving parts for sealing oil and air and preventing dust so far. In order to measure the electromagnetic shielding effectiveness of the conductive O-rings, we proposed a electromagnetic shielding evaluation setup for the O-ring. There are two ways to apply O-rings in narrow gaps, cylinder-fixing and plane-fixing. By the use of this setup, the electromagnetic shielding effectiveness of conductive O-rings can be evaluated from 10kHz to 1GHz for both fixing types.
The reflection and transmission characteristics of this setup and measured results of electromagnetic shielding effects are described. Anisotropic conductivity of the ring material and an equivalent circuit of the O-rings are discussed.

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Regarding compliance testing with existing guidelines on human exposure to ELF (extremely low frequency) magnetic fields, the nonuniformity of the fields has been one of the major concerns since guideline-level exposures are generally encountered in the direct vicinity of magnetic field sources such as electric power facilities and electric appliances. According to the guidelines, when the measured maximum magnetic fields exceed the specified field level, induced currents inside human bodies are to be investigated to check their conformity. However, this calculation still needs verification and requires massive computational resources, which are not readily applicable under practical exposure conditions. Therefore, a simple and relevant method of assessing nonuniform magnetic field exposure is highly desirable. In this paper, a method of obtaining an equivalent uniform magnetic field using a coefficient (the normalized induction factor) is investigated using a numerical calculation of induced current in anatomically correct human models. In addition, to assess the obtained coefficient easily, a simple method using a spherical model was proposed.

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