[in Japanese]

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In EDTV-II, a letterbox format is used for wide-aspect ratio. VT (Vertical-Temporal) and VH (Vertical High) helper signals are transmitted in the top and bottom black bars of a 4 : 3 transmitted signal. This paper proposes a motion-adaptive LD (Line Difference) /FD (Frame Difference) hybrid signal for the VT. In the motion adaptive hybrid method, the FD is used in stationary areas and the LD in moving areas. And because the signal with less energy is motion-adaptively selected, the hybrid signal is less visible on current receivers. Transmission noise in EDTV receivers can be reduced by coring and non-linear amplitude companding techniques. The proposed method can be implemented by adding only a few circuits to IDTV receivers (Clear-Vision receivers). Simulation results have clarified that the proposed signal is less annoying than the LD and FD signals.

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In response to the recent demand for high-density recording on an optical disk, the industry is now “going narrow track”. We have developed an adaptive learing control method capable of changing its learning according to track correlation, thus making it possible to avoid unnecessary learning during equipment vibration to avoid the lack of stability that is a problem for learning control, and to increase follow-up ability. As a result we have confirmed that track-error can be reduced to the equivalent noise level (0.1μm) and that stabilized operation with repetitive learning control system is possible.

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[in Japanese]

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This study used an optimization algorithm to mathematically investigate the light-regulation mechanism of the pupil. Regulation criteria were derived from consideration of the autonomic nervous system and the morphology of pupillary smooth muscles. An objective function was defined as follows : square of the rate of change of acceleration multiplied by an exponential function of time integrated over the entire movement. Variational calculus was used to obtain the equations expressing the pupil behavior. To evaluate the model, infrared pupillography was used to measure pupillary constriction and dilatation in response to step changes of light. The observed data was in good agreement with the model output, supporting our idea that the pupillary light response is regulated to maximize rapidity as well as smoothness.

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[in Japanese]

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