• 제목/요약/키워드: Visual factor

검색결과 1,043건 처리시간 0.023초

The Influence of Pituitary Adenoma Size on Vision and Visual Outcomes after Trans-Sphenoidal Adenectomy : A Report of 78 Cases

  • Ho, Ren-Wen;Huang, Hsiu-Mei;Ho, Jih-Tsun
    • Journal of Korean Neurosurgical Society
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    • 제57권1호
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    • pp.23-31
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    • 2015
  • Objective : The aims of this study were to investigate the quantitative relationship between pituitary macroadenoma size and degree of visual impairment, and assess visual improvement after surgical resection of the tumor. Methods : The medical records of patients with pituitary adenoma, who had undergone trans-sphenoidal adenectomy between January 2009 and January 2011, were reviewed. Patients underwent an ocular examination and brain MRI before and after surgery. The visual impairment score (VIS) was derived by combining the scores of best-corrected visual acuity and visual field. The relationship between VIS and tumor size/tumor type/position of the optic chiasm was assessed. Results : Seventy-eight patients were included (41 male, 37 female). Thirty-two (41%) patients experienced blurred vision or visual field defect as an initial symptom. Receiver operating characteristic curve analysis showed that tumors <2.2 cm tended to cause minimal or no visual impairment. Statistical analysis showed that 1) poor preoperative vision is related to tumor size, displacement of the optic chiasm in the sagittal view on MRI and optic atrophy, and 2) poorer visual prognosis is associated with greater preoperative VIS. In multivariate analysis the only factor significantly related to VIS improvement was increasing pituitary adenoma size, which predicted decreased improvement. Conclusion : Results from this study show that pituitary adenomas larger than 2 cm cause defects in vision while adenomas 2 cm or smaller do not cause significant visual impairment. Patients with a large macroadenoma or giant adenoma should undergo surgical resection as soon as possible to prevent permanent visual loss.

초등학생의 시력건강행위 영향요인 (Factors Related to Visual Health Promotion Behavior of Elementary School Aged Children)

  • 김정숙;오진주
    • 지역사회간호학회지
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    • 제12권1호
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    • pp.142-149
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    • 2001
  • The health education for elementary school students is a very important factor in the development of adult health practices. Particularly, eyesight is difficult to recover if lost. Therefore, prevention is better than cure. This study was conducted to investigate the factors that affect the visual health behavior of elementary school students and to furnish basic materials and directions for the promotion of elementary school health. The investigation was carried out for 4 days from 9. 18. 2000 to 9. 21. 2000 for 199 children in 3 elementary schools. A questionnaire was composed of 3 questions about general property. 20 questions about visual health behavior. 7 questions about visual self-efficacy. 5 questions about visual motivation. 16 questions about self-conception. 20 questions about the health locus of control. The data was analysed by an SAS program for t-test. ANOVA. correlation, and multiple regression tests. The results are as follows. 1. The visual health behavior of elementary school children was good (average 52.53). 2. For visual health behavior, school, year, and sex were influential factors. economic levels were not. 3. Visual health behavior had a significant correlation with visual self-efficacy, visual health motives and self-conception. but not with the locus of control. 4. In the multiple regression test, visual self-efficacy and self-conception were significant prediction factors -- the suitability of the regression model was 30.8%. Suggestions from the results are as follows: First, school year and sex had a significant influence on visual health behavior: therefore, it is necessary to consider these two factors when education programs are developed. Second, this study was carried out for students in a partial area only. Therefore, repeated studies for a large sample are necessary for the future.

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정상인에서 흔들림 균형 훈련시 간헐적인 방법과 지속적 방법에 의한 시각적 되먹임의 효과 비교 (Comparison between the Effect of Intermittent and Continuous Visual Feedback in Sway Balance Training with Normal Subjects)

  • 박준영;오신영;장진호
    • 한국전문물리치료학회지
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    • 제4권2호
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    • pp.59-65
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    • 1997
  • To improve the effect of balance training, visual feedback is usually used. During the training process there are some factors which decrease the effect. Neurophysiologically, the main negative factor is thought to be synaptic fatigue which decreases the sensitivity of synapses. The purpose of this study was to find a more effective balance training method. In this study, a total of 60 normal subjects-19~30 years old young males and females(M=30, F=30)-participated, and they were randomized as A, B, and C group, each group containing 20 subjects. First, all groups had a pre-test of sway balance. One minute later, A group was trained in sway balance by continuous visual feedback for 2 minutes, B group by intermittent visual feedback which had 4 sessions of 30 seconds each and a one minute rest break. C group was not trained at all. All groups had a post-test. Only B group had improved balance compared with C group by ANOVA. On the other hand, intermittent visual feedback was more effective than continuous visual feedback in sway balance training with normal subjects.

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CRT 모니터의 배경계조도가 영상의 시각인식에 미치는 영향 (The Effect of Background Grey Levels on the Visual Perception of Displayed Image on CRT Monitor)

  • 김종효;박광석
    • 대한의용생체공학회:의공학회지
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    • 제14권1호
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    • pp.63-72
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    • 1993
  • In this paper, the effect of background grey levels on the visual perception of target image displayed on CRT monitor has been investigated. The purpose of this study is to investigate the efficacy of CRT monitor as a display medium of image Information especially in medical imaging field. Tllree sets of experiments have been performed in this study : the first was to measure the luminance response of CRT monitor and to find the best fitting equation, and the second was the psychophysical experiment measuring the threshold grey level differences between the target image and the background required for visual discrimination (or various background grey levels, and the third was to develop a visual model that is predictable of the threshold grey level difference measured in the psychophysical experiment. The result of psycophysical experiment shows that the visual perception performance is significantly degraded in the range of grey levels lower than 50, which is turned out due to she low luminance change of CRT monitor in this range while human eye has been adapted lo relatively bright ambient illumination. And it Is also shown in the simulation study using the developed visual model that the dominant factor degrading the visual performance is the reflected light from the monitor surface by ambient light in general illumination condition.

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실내공간에 있어 자연광에 의한 시지각적 현상에 관한 연구 (A Study on the Visual Phenomenon of Natural Light in Interior Space)

  • 김주연
    • 한국실내디자인학회논문집
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    • 제13호
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    • pp.130-138
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    • 1997
  • This study is to present the visual phenomenon of natural light in the interior space. The continuously changing natural light define the visual phenomenon of the architectural space. First, the objective of this study was finding the importance of the visual phenomena which were generated from correlating natural right with the interior space. And the second was to categorize the factors of the visual phenomenon which can be useful factors for modern interior design practice. As a result of this study, two visual phenomena were classified. First; territorial phenomenon: dividing, partitioning, and sectioning by natural light, Second; phenomena by the inflow methods of natural light; a) by direct inflow; transparency, expansion, and floating, b) by filtering fixtures; the architectural structure, color, and the transluscent material, c) by dramatic spacial present of natural light, d) by the sense of direction of naturel light; continuity, and transformatiov. Found and classified each factor is not presented by itself, rather compounded forms. Because of the limited analysis of modern buildings, these found visual factors can not represent all phenomena. But if we practice these finding factors to design present interior space, it is sure of being very valuable factors to re-introduce the overlooked natural light into interior space.

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채광시스템 유형별 실내공간의 시각적 쾌적성에 관한 평가 (Visual Comfort Evaluation of Interior Spaces by Daylighting Systems)

  • 정인영;최윤석;안현태;김정태
    • KIEAE Journal
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    • 제6권1호
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    • pp.17-24
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    • 2006
  • Daylight is a critical factor in architecture, as it enhances the working efficiency and visual comfort of the people working inside. Even though, low transmittance glazing has been used in the most office buildings in Korea. And it is reduced visual comfort in a indoor environment. So, we need to evaluation of quality for various daylighting systems to improve visual comfort This study aims to evaluate the visual comfort in a indoor environment by different daylighting system. For the purpose, four different daylighting systems-conventional window, conventional window with interior lightshelf, differentiated window, differentiated window with interior lightshelf-were selected and a questionnaire survey with 50 subjects were conducted. The results are as follows. Regardless daylighting systems, a view has an effect on visual comfort. A conventional system and conventional system with lightshelf were highly correlated between comfort and warmth. In case of differentiated window system were correlated between comfort and openness. Also, differentiated window with interior lightshelf were highly correlated between comfort and stability.

Implementation of dynamic visual acuity testing system using optical see through head mounted display

  • Son, Hojun;Yun, Deokyoung;Kim, Jungho;Lee, Seunghyun;Kwon, Soonchul
    • International Journal of Internet, Broadcasting and Communication
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    • 제9권3호
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    • pp.70-77
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    • 2017
  • Dynamic visual acuity is used as an important factor to measure athletic performance in sports field. A study on visual acuity testing system using non-see head mounted display (NST-HMD) was conducted recently. However, the NST-HMD has a problem that the sense of space felt by the subject differs from the actual environment. This is because the view is blocked so that it is only implemented in a virtual space. This paper proposes a dynamic visual acuity testing system using optical see through head mounted display (OST-HMD). To do this, OST-HMD and NST-HMD comparative tests were conducted using existing K-D (King-Devick) charts. Experiments were performed on 30 subjects and their visual acuity was measured and analyzed by parametric statistics and one-sample T-test. The results of the study demonstrate the effectiveness of the proposed OST-HMD. This study is expected to use the visual inspection and training equipment of OST-HMD.

컴퓨터 애니메이션을 이용한 가로경관의 평가기법 연구 -정적 및 동적 시뮬레이션 기법의 비교- (A Study of Streetscape Evaluation Methods Using Computer Animation -A Comparison of Static and Dynamic Simulation Methods-)

  • 김충식;이인성
    • 한국조경학회지
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    • 제26권4호
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    • pp.1-13
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    • 1999
  • Previous research for visual assessment of streetscape employed static simulation methods to represent future landscape. However, streetscape is experienced sequentially, and thus dynamic simulations can be more effective. This study tried to adopt computer animation in the evaluation of streetscape, and examined its effects and possibilities. Three development scenarios for the redevelopment districts of Sokong-Ro and Banpo-Ro in Seoul were designed, and simulations were produced by three methods-photo-retouching, computer still image, and animation. A preference questionnaire was asked to 69 university students, and the effects of simulation methods on visual preference were examined. In addition, the frames of the animation were reclassed to identify the visibility of physical elements. The relationships between the visibility and visual preference were analyzed. The results showed that visual preference can be explained by three factors-Amenity, Tidiness, and Variousness-that account for 62.4% of the total variance, and the Amenity showed the highest proportion: 36.0%. Among the three simulation methods, animation showed the largest difference in preference for the most important factor(Amenity), and yielded the highest correlation between visibility of physical elements and Amenity. This result demonstrated that dynamic simulations can provide more accurate observation of visual changes, especially because the simulated landscape is experienced sequentially. The results also revealed that the sequential change in the visibility of physical elements can be examined easily and precisely by animation. This benefit of animation enables analysts to identify the points where the landscape varies the most, and thus visual preference should be evaluated.

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소비자 특성에 따라 선호되는 의류 점포의 비주얼 환경 요소 및 점포 유형 -점포 선택 기준에 의한 소비자 유형화를 기초로- (The Visual Environment Factors of the Store and the Store Types Preferred by Consumer Traits - Based on the Consumer Segmentation by Store Choice Criteria -)

  • 김선숙
    • 한국의류학회지
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    • 제28권8호
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    • pp.1112-1120
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    • 2004
  • The visual environment of the store is a very important factor to attract consumers into the store and make consumers purchase products. Therefore retailers should have concerns about store environments to differentiate their stores from other stores. Thus this study focused on visual environment of the store influencing consumer behavior. The concrete purpose of this study was to identify preferences of store environments and store types by consumer traits. First, the store choice criteria factors were examined and through the cluster analysis, several consumer groups were constructed. And then the visual environment factors of the store that consumers perceived important were identified and the visual environment factors of the store preferred by consumer groups were examined. Finally, store types preferred by consumer groups were examined. The findings of this study can assist store designers and retailers to set up a store environment or visual marketing strategies.

Cognitive factor Affecting Elderly in Community

  • Lee, Hye-Sun
    • International Journal of Advanced Culture Technology
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    • 제7권1호
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    • pp.150-154
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    • 2019
  • The purpose of this research is to identify major factors that influence the cognition the elderly in community. There was a significant correlation between the cognitive and visual perceptual skills of the elderly. The subject's cognitive skill was statistically higher for males by gender, for lower age group, and for higher level of education.