Lignin-modified phenolic resin (LPF) is prepared from methanol-soluble lignin by polymer blend methods (solvent blend and in situ polymerization) for application to environment-friendly brake friction material. The chemical structure of LPF is characterized by 13 C NMR, and TMA and DSC analyses are conducted to evaluate the thermal behaviors. Flexural tests and brake dynamometer tests of samples prepared from LPF by compression molding are carried out, and the results are compared with those for the samples prepared from commercial phenolic resin (PF). Results of the flexural test show that the addition of methanol-soluble lignin by solvent blend polymerization decreases the flexural strength. In contrast, in situ polymerized LPF exhibits flexural strength equivalent to that of PF. Results of the brake dynamometer test show that replacement of PF with methanol-soluble lignin increases the fade resistance of the brake friction material at elevated temperatures.

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Dependence of AC transport current losses on bending strains of two kinds of YBCO coated conductors (CCs) manufactured by IBAD/MOCVD and IBAD/PLD processes were investigated. The bending strains were applied to CCs samples by mounting the samples on U-shape sample holders consisted of straight and half-cylindrical sections. The bending strains to the superconductor layer were in tensile and compressive directions. The experimental results showed that the bending dependence of the AC transport current loss could be characterized by the amount of the deteriorations of the conductor critical currents dependent on structure changes of the superconductor layers due to the bending strains, regardless of the CCs manufacturing processes and the directions of the strains.

The recent imp ortance of d esigning and analyzing p ermanent magnet (PM) m otors taking into consid eration magnetic nonlinearity, torque ripple due to slot harmonics, and the eddy current loss of rare-earth magnets is increasing following an increase in the power densi ty of PM m otors. In addition, b oth th eir dr ive circuits and controllers should be tak en in to account tog ether si nce powerful and efficient motor drives are not achieved without current vector control. The finite element method (FEM) is widely used for designing and analyzing motors, but it is difficult to take current vector control into account. The magnetic circuit method has a simple analytical model and it is relatively accurate for calculations. Furthermore, electric-magnetic-mechanical coupled analysis can easily be carried out. We propose her e a meth od of calculating a m agnetic circuit for a PM motor with MA TLAB/Simulink, and discuss a demonstration simulated using current vector control.