[in Japanese]

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Wavelet analysis of eye movements when subjects gaze at a fixed target is proposed. This enables us to get a low-noise waveform of eye movement from raw data. Time derivatives of the data, i. e., velocity and acceleration, can be easily obtained using this method. The results are compared with the results obtained by a method that smooths the waveform of miniature eye movement using an FIR filter. Three applications are discussed : a representation of eye movement using chaotic attractor, a vector representation of acceleration of eye movement, and a statistical analysis to estimate minute skewness of miniature eye movement acceleration. The decrease of the blink component using wavelet analysis is also discussed. These applications can be used to evaluate the picture quality of new virtual and stereoscopic displays.

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To clarify the human mechanism that controls the relation between information processing and eye movements, we propose a fixation masking method that detects fixations and masks only those fixations. This paper describes how we examined the time required to obtain information on Japanese characters as well as the quantity of information acquired at each fixation point. Subjects were instructed to recognize incorrect characters from text they read. The results indicated that at least 67 ms were required to obtain visual information after viewing the stimulus. However, the masking affected the character recognition process in brain. From the distribution of fixation duration, approximately 130 ms were required to invoke the saccade once the subject had perceived the mask. Our results were different from Rayner's results. We assume that more complex information processing is required to read Japanese than to read English.

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Audio-visual information supplied by electronic media is rapidly beginning to occupy a greater part of our information environment than natural audio-visual information While positive effects on the user's brain are possible through contact with visual media, it is impossible to deny that negative effects are also possible To develop a basic and effective method to physiologically assess how visual media affects the human brain, we classified and investigated considerable data in this field, referring to outcomes of studies on sound amenities An α-EEG (Electroencephalogram) indicated assessment method is developed Its effectiveness is examined in a comparison between a High-Definition format and an NTSC format Results suggest the effectiveness of the method with statistical significance

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Visually induced perception of self motion, called vection, is an important element to decide physiological and psychological index of presence of virtual reality We constructed a measurement system of body sway by using visual wide field images and studied the influence of the different kinds of sway, sway direction, sway frequency, and the sway angle of images for body sway We found out that the body sway becomes larger when vertical image rolls larger, and the the correlation between image sway and body sway become 90° phase delay when the sway frequency of the image is higher than 0 3 Hz

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We analyzed the shooting technique of cameramen in relayed soccer telecast which is difficult to predict subjects'movement. We tested how cameramen confirm the subjests and how control the camera, by detecting their eye movement and velocity of the camera.
Outcomes therefrom :
·Cameramen shoot by repeatedly paying attention of approximately 50 msec at a time to thesurroundings.
·They always leave space in front of a moving subject, and the quantity of the space depends on the subject's size in the image and its velocity
·At an abrupt change in the subject's movement, sense it and perform the optimal correction in a very short time of about 300 msec.
·The maximum acceleration produced during panning was some 200 deg/sec² while on air and 300 deg/sec² while searching.

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Many traffic accidents are caused by drowsiness while driving. The purpose of this research is to detect a driver's blinking using facial images obtained by a TV camera and to estimate the driver's arousal level to prevent the occurrence of an accident due to drowsiness. This report presents the method used to obtain the facial images, which are not affected much by the change of the ambient light by day and by night owing to the infrared light sources. This paper also describes the method for extracting the blinks and measuring the blinking durations, which are not influenced very much by individual differences in eye shape. Furthermore, we experiment with the relation between blinking durations and arousal levels as compared with vehicle deviation from the lane and driver's answer to the question about drowsiness. We also examine a method for estimating arousal level which reflects individual characteristics.

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We present a method of representing a stepped-radius antenna by a uni-radius loaded antenna. By equalizing the reflection co-efficient of a loaded transmission line for the uni-radius loaded antenna to that of a compound transmission line for the stepped-radius antenna, the lumped impedance of the uni-radius loaded antenna is obtained. To confirm the equivalent relation, both antennas are analyzed numerically based on the electric field integral equation. As a result, current distributions and input impedances agree well. This concept is very useful for the analysis and physical understanding of the stepped-radius antenna, and for applications using the effect of the stepped radius. As a further application, an improvement of the input impedance characteristics of a stepped-radius antenna is also presented.

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The induction field model in vision can uniformly explain some experimental psychological results of a pattern recognition process. Many research activities make efforts to explain various psychological experiments of pattern recognition. However, there is no mathematical model that can uniformly explain these experiments. Recently, the field has been focused on as the concept that explains human visual perception. Furthermore, the induction field theory suggests the possibility of pattern recognition using “a filed”. This paper proposes and verifies a new pattern recognition model by induction field that can uniformly explain some psychological experimental results.

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