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Increasing the silicon content in non-grain-oriented (NO) electrical steel sheets is known to decrease iron loss by changing electrical resistivity and magnetostriction behavior. However, few studies on the effect of high silicon contents in grain-oriented (GO) electrical steel have been reported. One of the major differences in the iron loss of GO and NO is that excess eddy current loss, which has a strong relationship with the magnetic domain structure, is more dominant in total iron loss in GO. In this paper, high silicon GO was prepared by the CVD siliconizing method, which has the advantage that the silicon content can be changed without changing the crystal grain size and crystallographic texture of the specimen. It was found that iron loss was reduced as the silicon content was increased, and 6.5 mass% silicon steel showed about half the hysteresis loss of conventional 3 mass% silicon steel, but the eddy current loss in 6.5 mass% silicon steel was equivalent to or slightly larger than that in 3 mass% silicon steel. Magnetic domain observation and calculations suggested that this difference was a result of coarsening of the magnetic domains in the high silicon steel. [ABSTRACT FROM PUBLISHER]

Sound isolation has been achieved using a piezoelectric polymer film connected to a negative capacitance feedback circuit. A curved PYDE film was located in the middle of an acoustic tube and the transmission loss of sound through the film was determined in the audio frequency range. At any chosen frequency, the complete isolation of sound was achieved by adjusting the feedback, i.e. the complex capacitance of the circuit was matched precisely to that of the film. [ABSTRACT FROM AUTHOR]

Automation of assembly tasks has previously been tackled by many researchers. They mostly focused on the geometric constraints related to a considered task, e.g., relative configuration change between the peg and the hole. Such an approach, however, has a limited validity in the sense that, unlike ultraprecision assembly studied in the present study, it assumes that the dimensional tolerance is fairly large so that it allows change to the relative configuration of the two mating parts in an obvious fashion. The paper investigates what makes highly precise assembly tasks very difficult from the viewpoint of automation of the tasks. Tolerance considered in the present study is in the range of 3-9 μm. We focus on force sensory information involved in a high-precision peg-in-a-hole task of a polygon mirror unit because a position-based analysis under such a narrow dimensional tolerance seems inappropriate. A variety of insertion experiments are conducted by skilled and unskilled subjects for comparison purposes in which associated force signals are measured and analyzed [ABSTRACT FROM PUBLISHER]