[in Japanese]

View full abstract

The flyback transformer (FBT) is a kind of transformer which generates high voltages in TV sets, and ordinary flyback transformers sometimes cause extensive damage to TV sets due to shorting inside such as layer shorts. Twenty-five years have passed since we started production to rectify this problem. We have since developed new winding technology and production methods. Protection circuits have been improved and as a result of adapting this system, the former smoking or flaring in TV sets have largely been eliminated. We also studied new analysis technology to develop the accelerate Life Test which enables us to estimate the Life-Term of FBTs in a shorter time. We have had good results. At the same time the method of using flyback transformers has also been improved.

View full abstract

In this paper, we derive a weighted minimum description length (WMDL) criterion which is employed in adaptive model selection for an observed symbol series. The criterion is derived from a weighted log likelihood instead of the log likelihood which is the basis of the minimum description length (MDL) criterion. As an example, the proposed criterion is applied to the highly efficient arithmetic coding of high quality halftone images proposed by us. An equation calculating the proposed criterion for the coding model is derived. And an adaptive model selection method is constrcted based on the criterion. Efficiency of the proposed criterion in comparison with the MDL criterion in the example is shown by computer simulations.

View full abstract

In magnetic recording it is known that nonlinear distortion occurs in the recording process. Nonlinear distortion is separated into phase distortion and amplitude distortion; phase distortion is a shift in position and amplitude distortion is variability in the magnetization magnitude of magnetic transition in relation to the recording signal pattern. As nonlinear distortion increases the probability of errors in digital recording, it is important to be able to measure and analyse distortion. In this paper, we propose a new measuring method to estimate the nonlinear magnetic transition shift precisely from the dipulse response of the recording/reproduction system. Using this method, the nonlinear magnetic transition shift is measured by varying the amplitude, codebit reversal interval and the degree of low-frequency suppression of recording current using MP tape and Co-amorphous heads. As a result, nonlinear transition shift occurs and increases at a range exceeding 50% of the optimum recording current. It also increases at a range less than 0.5 μm of the distance between current and preceding magnetic transitions, and reaches a minimum value at a certain degree of low-frequency suppression of recording current.

View full abstract

[in Japanese]

View full abstract