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This paper describes a converter which changes Sub-Nyquist Sampling Encoding (MUSE) High-Definition Television broadcast signals to the 525-line format which is compatible with NTSC standard. It enables the viewer to receive HDTV signals broadcast in MUSE on a standard NTSC television. Special attention is paid to system scale and converter picture quality.

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A method to easily measure the magnetization characteristics of a magnetic head has been developed. Using this method, magnetomotive force and flux can be determined from both the current and voltage wavefroms observed when alternating current flows through a coil wound around a magnetic head. Computer data processing enables measurement of characteristics even at high frequencies (MHz Bands).
The magnetization characteristics of ferrite video heads were measured by this method, and were applied to the evaluation of magnetic heads. First, an absolute efficiency of the magnetic head is obtained from the magnetomotive force making a gap saturated. Next, the gap depth (which is related to video head life) is calculated from the saturated gap flux. These applications show the validity of using magnetization characteristics for the evaluation of magnetic heads.

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This paper proposes a method for determining parameters of two similar ellipses appearing at both ends of a cylindrical object. A contour of the object is mapped to a parametric curve by the Hough transform, where each point on the curve in the Hough transform space corresponds to a tangential line of the contour. The shape of the curve relates with parameters of both ellipses. The method uses these properties of the Hough transform. Parameters of ellipses are determined by extracting an edge of the Hough accumulation and by a curve-fitting for the edge with the least square method. Experimental results prove that the method is unaffected by gaps in the contour and by inside noise of the object.

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A simplified automatic equalizer operated at bit rate of over 100 Mbps is proposed for digital VTR. Transversal filter tap gains can be set using only binary data obtained from a data detecting comparator and an error detecting comparator by employing a modified adaptive zero-forcing algorithm. Therefore, the equalizer can be implemented with only a few components such as two comparators, a 2k-byte FIFO memory IC, a low speed DA convertor and a 16 bit-CPU.
The variable step size of tap gains and look-up table of equalizing error estimation are also introduced in order to shorten the tap gains convergence time. As a result, convergence times of less than 0.5 seconds can be achieved on the use of D2 format digital VTR channel.

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This paper describes CRT-gun specifics for the development of cathodes for larage-screen, high-resolution, and high-brightness CRT's. Cathodes currently being developed are discussed, and practical proposals to overcome high-current density problems including high operating temperature, are introduced.

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A simple method of processing full-color images for a color map display is proposed. The method consists of two procedures. First, the multi-level color dithering method is applied to the input full color image, and yielding an image represented by a reduced number of colors. Next, the conventional Popularity Algorithm is applied to the image. The use of dither effect and consequent proper color selection reduces degradation of image quality, i. e. inappropriate color reproduction and strong false contouring, common to conventional color selection methods.

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A method of location estimation for an outdoor mobile robot using a single scene image is proposed. To avoid obstacles, a camera is aimed upward. For location estimation, two top corners of a structure described in the map are utillized.
Camera angle values, i. e., elevation, bank, and heading, are also required to calculate location. These values can be evaluated by utilizing a vanishing point. This point is determined based on the horizontal movement of black pixels on slant edge lines and the parameterization of lines through limiting windows.
In the experiment, the location estimation error is less than 52 cm when camera-to-structure distance is about 35 m.

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A new technique for filter output signal ringing compensation is proposed. The technique is applicable for use in modern TV receivers and new systems such as IDTV and EDTV which require increased horizontal resolution.
The proposed compensation technique switches the filters with non-symmetric coefficients when edges are detected. This technique has the advantage of not effecting the filter frequency characteristics. Therefore the higher resolution components of the signal are not decreased, but ringing is removed.

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This paper presents the results of speaker recognition (identification and verification) experiments using back-propagation type neural networks. Voice samples of 5 male subjects over a long period of time (1-21 week) are pre-processed and used as input data. First, identification/verification accuracy was examined in several different pre-processing ways, resulting in a 100% correct identification rate and a 94. 1% verification rate. Next, the networks performance was investigated by varying the number of hidden units. Some text-independent speaker identification experiments were also carried out. By learning several pre-processed words to decrease the time varying information, networks achieved a correct identification rate of 91.3%.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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