ITE Technical Report
Online ISSN : 2424-1970
Print ISSN : 1342-6893
ISSN-L : 1342-6893
26.30
Displaying 1-16 of 16 articles from this issue
  • Article type: Cover
    Pages Cover1-
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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  • Article type: Index
    Pages Toc1-
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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  • Taketoshi Uchida, Keiji Uchikawa
    Article type: Article
    Pages 1-6
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    To investigate the cue of chromatic discrimination in the inhomogeneous field, we used uniformly saturated inhomogeneous chromatic stimulus. When color elements were small, the cue was the spatial mean of the stimulus. When they were large, the cue was the median color of the chromatic distribution. Changing one chromaticity into more saturated one did not affect which chromaticity was the cue. In some conditions the discrimination thresholds increased only in one direction. This indicates that a higher color mechanism that contains multi channels carries out the chromatic discrimination.
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  • Kazuhiro Sassa, Mamoru Takamatsu, Yoshio Nakashima, Santaro Nakajima
    Article type: Article
    Pages 7-11
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Progress of display terminals for computer systems are remarkable. For making the most out of the progress, understanding the characterristics of human visual information prosecing is very important. We introdused a model of visual objects on computer display in colors. And held sereis of visual search sessions to study the load of the visual information processing. The results showed higher saturation of the object on display increases the load of visual information processing. It suggests the importanse of consideration when we design visual objects for high-end computer displays.
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  • Mieko Yanagisawa, Keiji Uchikawa
    Article type: Article
    Pages 13-18
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    In the interocular suppression a stimulus presented in one eye is suppressed and a different stimulus in the other eye is perceived for a certain time interval. For strabismic observers the suppression continuously occurs between different retinal images made by the misalignment of eye positions. In our previous researches, the contrast sensitivity under interocular suppression was measured in normal and strabismic observers using luminance grating. It was obtained, in the 15 deg stimulus, that contrast sensitivity dropped remarkably on specific spatial frequency. In this research contrast sensitivity was measured using the chromaticity grating as suppression stimuli in order to investigate whether there is any spatial frequency characteristic which was obtaied by using luminosity grating.. In luminanace stimulus as a detection stimulus, we obtained a similar tendency in contrast sensitivities as our previous researches.
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  • Kazuya Matsubara, Michihiro Nakazawa, Satoshi Shioiri, Hirohisa Yaguch ...
    Article type: Article
    Pages 19-24
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Previous studies showed that contrast sensitivity peaks at around the location of a target attentively tracked. In this study, we investigated whether the spatial spread of the attentional facilitation was influenced by the range of probe locations. The results showed that the spatial spread of the contrast sensitivity function varied with the range of the probe location. This suggests that the spatial spread of attentional facilitation is controlled independently from the attentional facilitation center, which is found to be near the tracked taget.
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  • Ken-ichiro Yamamot, Kenji Mochizuki, Takeshi Naemura, Takahiro Saito, ...
    Article type: Article
    Pages 25-30
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    The HRTF (Head Related Transfer Function)-based methods of providing spatial sound images have not been capable of dealing with individual differences between human listeners yet. The HRTF varies from person to person, and this individual HRTF varies with the direction of sound source. This paper focuses on this directional variation of the individual HRTF. The principal component analysis is applied to draw loci of the variation in an orthogonal basis space. Each locus corresponds to single individual HRTF and the loci are utilized for clustering the individual HRTFs. Some typical HRTFs can be extracted from clusters and it is shown that they are useful for compensating the individual differences in HRTFs.
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  • Yasuhiro Takaki
    Article type: Article
    Pages 31-36
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    A new 3D display technique is proposed which offers faithful 3D images. A number of horizontal parallax images are displayed by a number of afocal imaging systems aligned in a modified two-dimensional array, and a common vertical viewing zone is produced by a vertical diffuser. The technique does not require wearing any 3D glasses and several persons can observe 3D images simultaneously. Color and animated 3D images can be displayed. Observers can percept 3D images with binocular disparity, ocular vergence, motion parallax, and accommodation. There are two types of configurations to display multiple parallax images; image-level multiplexing and pixel-level multiplexing. A prototype having 64 parallaxes is constructed based on the former configuration.
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  • Hideaki Maehara, Koji Wakimoto, Kazuo Kamata
    Article type: Article
    Pages 37-41
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Recently various case studies on interface of information apparatus for aged people have been reported. For example, there is an experiment of display image modification based on aged people's vision characteristics for car navigation systems. The approach in these studies takes advantage of measured and analyzed result of quantitative user characteristics so that behavior of information apparatus matches users. However this approach hardly works in cases that quantitative analysis of user characteristics is difficult or there is trade-off among many factors. Accordingly we propose a model which adapts the interface without analysis of user characteristics. We call this model as "compensation model", because we set our goal on equality of accessibility to information by all users. In this paper, we described the compensation model and an experiment that shows necessity of the compensation.
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  • Yuji Shimizu, Yoshihide Tamori
    Article type: Article
    Pages 43-48
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    The moment which we come across some good idea is so-called "aha!" moment. When we find out the target in the visual search task, we would get a impression of "aha!" Since the moment is, in other word, the moment of getting an inspiration, we can not expect when such a modality-independent moment comes out. We have observed multi-channel MEG during a few second up to the moment of "aha!" in order to understand how the localized activities move around the whole brain as related to the moment of "aha!" The results of analysis suggest equivalent current dipoles thus the localized neural activities appear in the superior frontal gyrus and anterior cingurate gyrus during the moment of "aha!".
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  • Haruka Nishimura, Ko Sakai
    Article type: Article
    Pages 49-54
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    We propose cortical mechanisms underlying the figure-ground determination that is an essence of surface perception. The underlying mechanism for figure-ground segmentation has not been clarified, although neurons in monkey's V2 show the selectivity to figure. A recent physiological study by H. Zhou, H. S. Friedman, and R. von der Heydt [1] has shown that the activities of neurons in V1, V2, and V4 correspond to figure/ground, a number of which are co-selective to the contrast configuration of stimuli. Previous models have utilized T-junction and ownership-junction for the determination of figure. We propose a netword model for determining figure/ground based on the combination of contrast information.
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  • Hiroki TAMURA, Zheng TANG, Masahiro ISHII, Koichi TASHIMA
    Article type: Article
    Pages 55-60
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Recently, many new bio-computers have been widely researched and some bio-computer-models have been proposed such as neural-computers. In immunology, many biological immnue systems are researched and some pattern recognition models based on immune networks have been proposed. In this paper, we propose a immune network with diversity. The proposed immunity network is applied to a pattern recognition system, arid the characteristic is shown.
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  • Tadanori Sakaguchi, Toshikazu Matsui
    Article type: Article
    Pages 61-66
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Experimental results on the correspondence between motion appearances and accommodative responses to multiple apparent motion stimuli have made us predict the existence of a serial multichannel structure in human vision. In this report, in order to computationally verify the validity of the existence, it is examined whether the cooperative motion detection model characterized by the same serial multichannel structure can theoretically reproduce the experimental results by being applied to the same multiple apparent motion stimuli. Consequently, it is shown that the computational results agree well with the experimental ones in the following aspects. (1) There exists a critical spatial frequency in which two kinds of motion perception is replaced by a single motion perception. (2) A critical spatial frequency is shifted to higher frequencies with the average temporal frequency and the number of still images per a spatial period of the presented stimuli. (3) Two kinds of accommodative states are fundamentally induced depending on which apparent wave's motion observers pay attention to. (4) The accommodation error for the second apparent wave increases a little as the average temporal frequency and the number of still images per a spatial period are decreased in the single motion perception region. The above results mean that the existence of a serial multichannel structure in human vision has been supported from a computational point of view.
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  • Joon-Bo Shim, Yoshinori Takeuchi, Toshiharu Mukai, Noboru Ohnishi
    Article type: Article
    Pages 67-72
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    The Kanade-Lucas (KL) feature tracker is one of the better matching methods. However it fails to find corresponding points of two images when image motion is quite large. We propose the feature point matching method, making use of affine transformation and correlation so that the KL method works well for large image motion. First, the KL method is used for matching points. Second, correlation of two matched points between the first and the second image obtained by the KL method is used to discriminate between well matched points and poorly matched points. Third, all the points to be matched in the first image are transformed on the second image by affine transformation of well matched points alone. Finally, correlation is used to find the best matching point around the transformed point. Real image data has been used to test the proposed method, and excellent results have been obtained with an average error of 0.811 pixels.
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  • Article type: Appendix
    Pages App1-
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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  • Article type: Appendix
    Pages App2-
    Published: March 20, 2002
    Released on J-STAGE: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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