• Title/Summary/Keyword: function of eye

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Development for a method of measurement in equilibrium sense (평형감각 측정기술의 개발)

  • 이문영;정영자;김규겸;이성호;박병림
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 1999.03a
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    • pp.3-6
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    • 1999
  • The study was performed to evaluate the sense of equilibrium by means of rotary chair system in middle school girls with dance learning. Control of equilibrium, which is the most important function in dancing, is maintained by vestibular, visual, and proprioceptive inputs. Experimental groups were divided into trained group with dance (experimental group, 13~14 ys, n=15) and untrained group (control group, 13~14 ys, n=15). experimental group was trained by programmed dancing for 12 weeks, 45 min/day and 5 day/week. Gain of eye movement was measured for vestibulocular reflex (VOR), visual vestibular stimulation (VVOR), optokinetic stimulation(OKN), and visual fixation (VFX). The gain of eye movement at higher than 0.08 hz was significant decrease in experimental group, and VVOR showed the similar fashion to VOR. The gain in OKN and VFX was not significant difference between experimental and control groups. These results suggest that programmed training of dancing improves control of balance by adaptation of the vestibular function, and rotary chair system would be useful to evaluate the sense of equilibrium ability.

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Development of Training Instruments on Visual functions using HMD type Display and Investigation of its Demand

  • Lee, Seong Jae;Oh, Se Hyun
    • International Journal of Advanced Culture Technology
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    • v.6 no.3
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    • pp.201-210
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    • 2018
  • We constructed 3-D images by HMD (Head Mount Display) type and polarization technique through which a training instrument of binocular function based on clinical vision therapy was developed and investigated its demand. To design the instrument that performs Test- Diagnosis - (Prescription) - Training - Treatment we provided a customized training method for the trainers using optical IT instruments of binocular test. Through the contents and the instruments of the vision therapy technology developed in this work we can replace the current vision test instruments to those costing 60% lower price in eye clinics and eye glasses shops. By replacing the existing vision test instruments it is possible to create a new market of the vision therapy in vision training instruments.

The Immediate Effects of Dynamic Stretching and Static Stretching Using a Wedge Board on the Balance Ability and Jump Function of Healthy Adult

  • Ji, Ye-ri;Hong, Yoo-sun;Lee, Dongyeop;Hong, Ji-Heon;Yu, Jae-Ho;Kim, Jin-Seop;Kim, Seong-gil
    • The Journal of Korean Physical Therapy
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    • v.33 no.6
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    • pp.286-291
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    • 2021
  • Purpose: This study aims to measure the improvement of balanced ability and rapid response of 30 healthy adults by performing dynamic stretching, static stretching, and sargent jump. Methods: The sample 30 peoples without any musculoskeletal disease who volunteered to be the subject of the study. We measured all subjects on following metrics to evaluate the function and stability under the normal condition, with dynamic stretching (DS) group, static stretching (SS) group: vertical jump height and reaching distance Anterior, Posteromedial, Posterolateral and NO (Normal eye open), NC (Normal eye close), PO (Pillow with eye open), and PC (Pillow with close eye) were evaluated. All measures were analyzed using independent t-test and One-way repeated Anova. Results: There was a significant increase in SJH (Sargent jump) in both groups (p<0.05). In Y-balance test, there was a significant increase in both groups except for the ANT (Anterior) direction, and there was a significant increase only in the SS group in the ANT (Anterior) direction (p<0.05). There was no significant difference between the DS group and the SS group (p>0.05). There was no significant improvement in ST (Stability Index) and WDI (Weight Distribution Index) in both groups (p>0.05). Conclusion: Both DS and SS showed significant improvement in SJH and Y-balance tests, which are dynamic functions, but had no significant effect on static balance ability.

Analysis of cross-population differentiation between Thoroughbred and Jeju horses

  • Lee, Wonseok;Park, Kyung-Do;Taye, Mengistie;Lee, Chul;Kim, Heebal;Lee, Hak-Kyo;Shin, Donghyun
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.8
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    • pp.1110-1118
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    • 2018
  • Objective: This study was intended to identify genes positively selected in Thoroughbred horses (THBs) that potentially contribute to their running performances. Methods: The genomes of THB and Jeju horses (JH, Korean native horse) were compared to identify genes positively selected in THB. We performed cross-population extended haplotype homozygosity (XP-EHH) and cross-population composite likelihood ratio test (XP-CLR) statistical methods for our analysis using whole genome resequencing data of 14 THB and 6 JH. Results: We identified 98 (XP-EHH) and 200 (XP-CLR) genes that are under positive selection in THB. Gene enrichment analysis identified 72 gene ontology biological process (GO BP) terms. The genes and GO BP terms explained some of THB's characteristics such as immunity, energy metabolism and eye size and function related to running performances. GO BP terms that play key roles in several cell signaling mechanisms, which affected ocular size and visual functions were identified. GO BP term Eye photoreceptor cell differentiation is among the terms annotated presumed to affect eye size. Conclusion: Our analysis revealed some positively selected candidate genes in THB related to their racing performances. The genes detected are related to the immunity, ocular size and function, and energy metabolism.

Recording and interpretation of ocular movements: spontaneous and induced nystagmus

  • Jin-Ju Kang;Seoyoung Choi;Seunghee Na;Sun-Young Oh
    • Annals of Clinical Neurophysiology
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    • v.25 no.1
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    • pp.10-18
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    • 2023
  • The ultimate purpose of eye movement is to maintain clear vision by ensuring that images of observed objects are focused on the fovea in the retina. Accurate evaluation of ocular movements, including nystagmus and saccadic intrusions, provides very useful information for determining the overall function and abnormality of the complex oculomotor system, from the peripheral vestibular system to the cerebrum. Eye movement tests are therefore essential for the accurate diagnosis of patients who complain of dizziness and imbalance. They help to predict lesion locations from the peripheral vestibular system to the central cerebral cortex and play an important role in differentiation from other diseases. The methodology of recording and interpreting ocular movements using video-oculography are described in this review article.

Research on Visual Function Before and After Prescription of Vertical Prism (수직사위 교정 전·후 시기능 변화에 대한 연구)

  • Kim, So-ra;Lee, Gi-yung;Park, Hyun-ju
    • Journal of Korean Ophthalmic Optics Society
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    • v.20 no.2
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    • pp.229-235
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    • 2015
  • Purpose: This study was undertaken to study on visual function before and after prescription of vertical prism. Methods: 80 subjects (10-30ages) who had been precribed vertical prism and 1 year after they were represcribed vertical prism. Results: Phoria (p=0.000), supra vergence (p=0.000), NPC (p=0.003), NPA (right eye) (p=0.005), NPA(left eye) (p=0.000) showed a significant change. Conclusion: Vertical prism prescription was reduced during revisit. Supra vergence, NPC, NPA(right eye), NPA(left eye) showed a significant change. Binocular Accommodative lag was not associated with vertical prism prescription and binocular vision findings.

Optimization of optical design for Eye Glass Display

  • Moon, H.C.;Kim, T.H.;Park, K.B.;Park, Y.S.;Seok, J.M.;Kim, H.W.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1603-1606
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    • 2005
  • Eye Glass Display (EGD) with microdisplay to realize the virtual display can make the large screen, so virtual image has been developed by using microdisplay panel. This paper shows study of low cost lens design and simulation for microdisplay system with 0.6" Liquid Crystal on Silicon (LCoS) panel. Lens design optimized consider to spherical aberration, astigmatism, distortion, and chromatic aberration. Code V is used and it designed an aspheric lens about exit pupil 6mm, eye relief 20mm and 35 degree of field of view (FOV). With the application this aspheric lens to LCOS type's microdisplay, virtual image showed 50 inch at 2m. One side of the aspheric lens was constituted from diffractive optical element (DOE) for the improvement in a performance. It had less than ${\pm}2%$ of distortion value and modulation transfer function in axial had 20% of resolution with 30 lp/mm spatial frequency. The optical system is suitable for display of 0.6"-diagonal with SVGA.

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A New Bussgang Blind Equalization Algorithm with Reduced Computational Complexity (계산 복잡도가 줄어든 새로운 Bussgang 자력 등화 알고리듬)

  • Kim, Seong-Min;Kim, Whan-Woo
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.22 no.10
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    • pp.1012-1015
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    • 2011
  • The decision-directed blind equalization algorithm is often used due to its simplicity and good convergence property when the eye pattern is open. However, in a channel where the eye pattern is closed, the decision-directed algorithm is not guaranteed to converge. Hence, a modified Bussgang-type algorithm using a hyperbolic tangent function for zero-memory nonlinear(ZNL) function has been proposed and applied to avoid this problem by Filho et al. But application of this algorithm includes the calculation of hyperbolic tangent function and its derivative or a look-up table which may need a large amount of memory due to channel variations. To reduce the computational and/or hardware complexity of Filho's algorithm, in this paper, an improved method for the decision-directed algorithm is proposed. In the proposed scheme, the ZNL function and its derivative are respectively set to be the original signum function and a narrow rectangular pulse which is an approximation of Dirac delta function. It is shown that the proposed scheme, when it is combined with decision-directed algorithm, reduces the computational complexity drastically while it retains the convergence and steady-state performance of the Filho's algorithm.

A Method for Slow Component Velocity Measurement of Nystagmus Eye Movements using RLSM (RLSM을 이용한 안구운동의 저속도 측정방법에 대한 연구)

  • 김규겸;고종선;박병림
    • The Transactions of the Korean Institute of Power Electronics
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    • v.7 no.6
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    • pp.546-553
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    • 2002
  • A control of the body posture and movement is maintained by the vestibular system, vision, and proprioceptors. Especially, vestibular system has a very important function that controls the eye movement through vestibuloocular reflex and contraction of skeletal muscles through vestibulospinal reflex. However, postural disturbance caused by loss of vestibular function results in nausea, vomiting, vertigo and loss of craving for life. Lose of vestibular function leads to abnormal reflex of eye movements named nystagmus. Analysis of the nystagmus is needed to diagnose the vertigo, which is performed by means of electrooculography(EOG). The purpose of this study is to develop a computerized system for data processing and an algorithm for the automatic evaluation of the slow component velocity(SCV) of nystagmus induced by optokinetic(OKN) stimulation system. A new algorithm using recursive least square method(RLSM) to detect SCV of nystagmus is suggested in this paper. This method allows a fast and precise evaluation of the nystagmus, through artifact rejection techniques. The results are depicted in this paper.

Robust Face and Facial Feature Tracking in Image Sequences (연속 영상에서 강인한 얼굴 및 얼굴 특징 추적)

  • Jang, Kyung-Shik;Lee, Chan-Hee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.9
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    • pp.1972-1978
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    • 2010
  • AAM(Active Appearance Model) is one of the most effective ways to detect deformable 2D objects and is a kind of mathematical optimization methods. The cost function is a convex function because it is a least-square function, but the search space is not convex space so it is not guaranteed that a local minimum is the optimal solution. That is, if the initial value does not depart from around the global minimum, it converges to a local minimum, so it is difficult to detect face contour correctly. In this study, an AAM-based face tracking algorithm is proposed, which is robust to various lighting conditions and backgrounds. Eye detection is performed using SIFT and Genetic algorithm, the information of eye are used for AAM's initial matching information. Through experiments, it is verified that the proposed AAM-based face tracking method is more robust with respect to pose and background of face than the conventional basic AAM-based face tracking method.