This paper proposes an image compression scheme using a generalized harmonic analysis (GHA) in combination with vector quantization (VQ) for improving image quality. VQ is one of the image compression technology. VQ has the feature that mosquito-noise does not arise, however it has a problem in compression in a low frequency domain. In order to improve this problem, the proposed scheme codes a low frequency component by a GHA, and applies VQ to the region with a GHA' s error more than a threshold. A GHA is able to analyze a signal in a low frequency domain with a good performance. By using a GHA and VQ together, the proposal scheme obtains a better performance than VQ. Finally, the proposed scheme is evaluated. The result of evaluation, the proposed technique has 0.2 [dB] to 0.5 [dB] image quality better than VQ.

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An earthenware reconstruction system, which can automatically reconstruct earthenware from given potsherds has been developed, in order to support the work of archaeologists. The existent system extracts the contour from given image of potsherd, and detects a candidate of joint by comparison of their contour shape. In this research, we utilize their color and surface pattern as clues in reconstructing earthenware as archaeologists do. This paper describes a method that extracts the feature of color and shape from input images, and proposes an effective algorithm of joint detection, which utilizes both color and shape feature. We have implemented the algorithm into the earthenware reconstruction system, and also report good performance results for excavated potsherds.

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In this research, a Chinese Learning Support System that allows one to conduct self-learning, anytime and anywhere, has been developed. In this system, advanced Virtual Assistants are proposed to provide learning support functions, which give learners appropriate chances for their study, and promote their learning motivation. Furthermore, these virtual assistants provide learners study statistics information including their study history so that they can easily understand their progress in learning. The results of evaluation experiences show effectiveness of the proposed concept of Virtual Assistants for learning of Chinese Language.

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We proposed novel screen systems for magnifying stereographic depth lengths, such as a flat screen, a spherical dome screen and an oval dome (horn-type) screen as well as theoretical mechanisms for magnifying depth length. We fabricated the screens and confirmed the correspondence of theoretical and experimental values. The magnification ratio of the oval dome screen to the flat screen increased from 1 to 6.93 as the screen curvature parameter b increased from 1 to 4. Furthermore, we achieved depth distortions and obtained their eliminations.

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This paper describes the experiments and analysis of the interception of personal computer's display image using emanation of electromagnetic wave. We used personal computers as the targets and experimented on reconstruction of screen information under the following equipments and environments; (1) using a near magnetic field probe, (2) using an antenna from away place, (3) using an injection probe over power supply cable. From the result of (1), we show that the slight difference in the synchronous frequency of video signal among PCs will become the key which recognizes the target. In the experiment (2), we succeeded from about 4 meters away place with frequency which is inside of VCCI regulations. In the experiment (3), we succeeded the interception from about 30 meters away place, and we found that the result depends on position relation between a probe and AC adapter.

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