• Title/Summary/Keyword: peripheral vision

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A New Finding-peripheral Vision Phobia: A Possible Subtype of Social Phobia

  • Jang, Su Hee
    • Journal of Acupuncture Research
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    • v.31 no.1
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    • pp.159-165
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    • 2014
  • Background and objectives : Social phobia is a nervous anxiety characterized by one or more constant fear in social activity or specific situation which causes serious damage to individual's social functions leading to chronic functional impairment when it is untreated. The objective of this study is to report a new finding of a possible subtype of social phobia according to a case survey and study of sufferers found via online support group. Methods : A single case review using survey and interview on patient was employed. Following a no-treatment baseline period for examination and interview, biweekly acupuncture treatment with interview for in-depth examination was delivered for 6months. Also, for in-depth investigation of peripheral vision phobia, survey questionnaire was done by the members of a Korean support group on on-line social group forum. Result : A new type of social phobia which has not yet been reported nor mentioned in any journals, namely called 'peripheral vision phobia' has been identified. Biweekly acupuncture treatment reached a comfort state of mental status on one case of patient with social phobia. Limitation : Due to the shift of environment on patient's part, the termination of the school session at where the phobia occur the most, the reoccurrence of the phobia is yet to be examined. Also, the generalization of the new type of phobia as a subtype only by reviewing one case alone with survey interview of on-line social group has limitation. Conclusion : The result of the case review suggests that 'peripheral vision phobia' is strictly concentrated on malfunctioning of peripheral vision without functional or organic hindrance of pupils or of any parts of eyes including eye muscles due to peripheral vision phobia. PVP is similar to social phobia and it may be a subtype of social phobia, however, since etiology, diagnosis, medical treatment methods are under researched, investigation is yet to be done.

Evaluation of Vision-Specific Quality of Life between Spectacles and Contact Lens Wearers (안경과 콘택트렌즈착용자의 삶의 질 평가)

  • Kang, Sue Ah;Kim, Jung Hee
    • Journal of Korean Ophthalmic Optics Society
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    • v.12 no.3
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    • pp.111-115
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    • 2007
  • Purpose: The aim of this study was to assess vision-related quality of life and modes of refractive error correction. We administered NEI-VFQ (National Eye Institute Visual Function Questionnaire) to 137 subjects in two modes of refractive error correction: spectacles and contact lens wearers. The NEL-VFQ was developed to assess vision-related quality of life with respect to 1) visual symptoms 2) social function as well as difficulty with tasks and symptoms 3) economic issues and health concerns 4) psychological well-being. The NEL-VFQ was translated from English into Korean. Methods: All data were analyzed using SAS 8.0. Student's T-test was conducted to determine significant differences in each of the subscale (${\alpha}=0.05$). Result: The Peripheral Vision subscale score ($mean{\pm}SD$) was $52.2{\pm}32.7$ for the spectacle wearers, $88.6{\pm}18.1$ for contact lens wearers; the spectacle wearers' Peripheral Vision score was significantly lower than contact lens wearers (p=0.0001). There were also significant differences between two groups detected in Color Vision (p=0.001), General Vision (p=0.01) and Health Perception (p=0.01). Conclusion: Contact lens wearers and spectacle wearers were mostly high vision-related quality of life except General Vision and Health Perception. Especially, contact lens wearers were higher vision-related quality of life than spectacle wearers. Further studies on developing of good quality of contact lens will be needed to improve quality of life in ametropia.

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A Study on Colour Appearance along the Variance of Colour Stimulus and Background Lightness at Peripheral Vision (주변시 시각에서 색채 자극과 배경의 밝기에 따른 컬러 어피어런스 연구)

  • Hong, Ji-Young
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.18 no.2
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    • pp.19-25
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    • 2018
  • A scientific and systematic approach for digitally representing colours is essential for improving image quality. Therefore, there is a need for objectively analysing such approaches. Studies regarding display systems, which can reflect human visual characteristics in the digital media environment, and associated international standards at the forefront, have already caused significant impact. Colour is one of the most important factors employed for evaluating the overall image quality of displays. The proposed study focusses on colour properties which are based on the characteristics of the human peripheral vision area, with the primary objective of reproducing digital colours which can simulate human visual characteristics in the digital media environment. The proposed study aims at identifying digital colour characteristics which can vary according to the level of background lightness and the size of colour stimuli. Based on the evaluation results obtained through psychophysical experiments, a method has been proposed for determining peripheral vision characteristics which vary according to the increasing size of a colour stimulus, thereby digitally reproducing them on displays.

Moving Target Tracking using Vision System for an Omni-directional Wheel Robot (전방향 구동 로봇에서의 비젼을 이용한 이동 물체의 추적)

  • Kim, San;Kim, Dong-Hwan
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.10
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    • pp.1053-1061
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    • 2008
  • In this paper, a moving target tracking using a binocular vision for an omni-directional mobile robot is addressed. In the binocular vision, three dimensional information on the target is extracted by vision processes including calibration, image correspondence, and 3D reconstruction. The robot controller is constituted with SPI(serial peripheral interface) to communicate effectively between robot master controller and wheel controllers.

Study on Physiological Summation in Peripheral Retina for Eccentric Viewing Training (중심외주시 훈련용 주변부 망막의 생리적 가중에 관한 연구)

  • Seo, Jae-Myoung;Lee, Ki-Young
    • Journal of Korean Ophthalmic Optics Society
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    • v.18 no.4
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    • pp.489-493
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    • 2013
  • Purpose: This study was to investigate peripheral vision and provide people with macular degeneration with a guideline for eccentric viewing training. Methods: 30 adult subjects with normal vision took part in this study. The lateral area of $20^{\circ}$ eccentricity from the fovea of right eye was only used to measure the physiological summation. The target was sinusoidal vertical gratings within a circular aperture. The critical points in spatial and temporal summation was found to compare each other for 0.7 cpd and 3.0 cpd, respectively. Results: Critical duration and contrast sensitivity for 0.7 cpd were 540 ms and 1.1, and 315 ms and 0.98 for 3.0 cpd respectively. The critical degrees and contrast sensitivity for 0.7 cpd were $11.3^{\circ}$ and 2.8, and $5^{\circ}$ and 2.63 for 3.0 cpd respectively. Conclusions: The critical point in peripheral vision reaches relatively faster than the one in central vision. It is recommended to train the peripheral retina under the lower spatial frequency more frequently for a short time than constantly for a long time.

A Comparison Study of Colour Perception considering Peripheral Vision on Display Device (디스플레이상에서 주변시를 고려한 색채 인지 비교 연구)

  • Hong, Ji-Young;Park, Yun-Sun
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.1
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    • pp.43-53
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    • 2016
  • In this study, under the assumption that there may be differences in colour attributes that can be perceived according to the brightness of the background and the size of the colour stimulus, a test was conducted where colour matching was done for stimulus sizes of $10^{\circ}$ and $20^{\circ}$ in terms of peripheral vision by varying the background brightness. The test results showed that depending on the background brightness and the specific combinations of the Munsell colour attributes used as the test stimulus, colours can be perceived differently even if they are the same colours. In addition, in contrast to findings from previous studies on colour perception according to the stimulus size, it was found that even if the size of the colour stimulus is relatively small, colours can be perceived more colourfully or more brightly with changes in the background brightness. Based on the findings of this study, degradation in image quality can be improved, which may occur when the size of the input image is changed at a later time, and also, contributions can be made when it comes to the reproduction of effective sold three-dimensional structures that reflect visual qualities when processing 3D holographic imagery, in addition to 2D imagery.

Fuzzy Screen Detector for a Vision Based Pointing Device (비젼 기반의 포인팅 기기를 위한 퍼지 스크린 검출기)

  • Kho, Jae-Won
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.58 no.3
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    • pp.297-302
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    • 2009
  • In this paper, we propose advanced screen detector as a tool for selecting the object for tracking and estimating its distance from a screen using fuzzy logic in vision based pointing device. Our system classifies the line component of the input image into horizontal and vertical lines and applies the fuzzy rule to obtain the best line pair which constitute peripheral framework of the screen. The proposed system improves the detection ratio for detecting the screen in relative to the detector used in the previous works for hand-held type vision based pointing device. Also it allows to detect the screen even though a small part of it may be hidden behind other object.

A study on the colour properties movement phenomenon reflecting visual characteristics on display (디스플레이에서 시지각 특성이 반영된 색상 속성 이동 현상 연구)

  • Hong, Ji-Young
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.18 no.3
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    • pp.29-34
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    • 2018
  • The digital colour reproduced on a display can be transferred to the image through various colour spaces, and the colour transferred to the image is one of the most important factors, among both subjective and objective factors, in image quality evaluation. Therefore, the digital colour must be continuously studied objectively and quantitatively along with the display development. At the same time, the subjective evaluation should be accompanied by systematic and quantitative research as the visual characteristics must be fully reflected. In this study, we applied different lightness levels of the background in order to examine the movement phenomenon of colour properties among the digital colour properties reproduced on the display. A psychophysical experiment was conducted for the condition where various colours were presented in the background, and the size of the colour stimulus was divided into the foveal vision and peripheral vision. Based on the evaluation results of the experiment, the colour properties movement phenomenon is identified according to the lightness of the background and the size of the colour stimulus for five colours among KS basic colours selected by experimental stimulus. Furthermore, a research direction to reproduce colour on displays in the future is proposed.

Perceptual Quality-based Video Coding with Foveated Contrast Sensitivity (Foveated Contrast Sensitivity를 이용한 인지품질 기반 비디오 코딩)

  • Ryu, Jiwoo;Sim, Donggyu
    • Journal of Broadcast Engineering
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    • v.19 no.4
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    • pp.468-477
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    • 2014
  • This paper proposes a novel perceptual quality-based (PQ-based) video coding method with foveated contrast sensitivity (FCS). Conventional methods on PQ-based video coding with FCS achieve minimum loss on perceptual quality of compressed video by exploiting the property of human visual system (HVS), that is, its sensitivity differs by the spatial frequency of visual stimuli. On the other hand, PQ-based video coding with foveated masking (FM) exploits the difference of the sensitivity of the HVS between the central vision and the peripheral vision. In this study, a novel FCS model is proposed which considers both the conventional DCT-based JND model and the FM model. Psychological study is conducted to construct the proposed FCS model, and the proposed model is applied to PQ-based video coding algorithm implemented on HM10.0 reference software. Experimental results show that the proposed method decreases bitrate by the average of 10% without loss on the perceptual quality.