• Title/Summary/Keyword: Low Vision

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Changes in Spherical Aberration and Coma Aberration after Wearing Aspheric Soft Contact Lens in Young Myopes (젊은 성인 근시안에서 비구면 소프트 콘택트렌즈 착용 후 구면수차와 코마수차의 변화)

  • Lim, Dong-Kyu;Kwon, Hyeok;Lee, Koon-Ja
    • The Korean Journal of Vision Science
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    • v.20 no.4
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    • pp.469-482
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    • 2018
  • Purpose : We investigated the change of spherical and comma aberrations after wearing aspheric soft contact lens (ASCL) in young myopes. Methods : Fifty young myopes ($23.15{\pm}1.70years$, spherical equivalent: $-2.90{\pm}1.75D$) were recruited and refractive errors were corrected using ASCL (Biotrue, Bausch+Lomb, USA). High order aberrations were measured in the 4 mm pupil size using the wavefront analyze and pupil sizes were measured with a pupillometer at the modes of scotopic condition (light off) at 3.5 m in the 100 lx illuminance condition. Results : Spherical aberrations and coma aberration of the 20s myopes were $0.026{\pm}0.031{\mu}m$ and $0.078{\pm}0.039{\mu}m$ respectively, and $0.019{\pm}0.026{\mu}m$ and $0.082{\pm}0.038{\mu}m$ after ASCL wear that spherical aberration was decreased and coma aberration was increased. However, spherical aberration was decreased in the 68% of the subject have positive spherical aberration, and increased in the 11% of the subject have negative spherical aberration. Coma aberration was increased in the 53% of the subject, did not change in the 19% of the subjects, and decreased in the 28% of the subject. Spherical aberration was not different with the refractive errors in low and moderate myopies, however, coma aberrations was higher in the higher myopes. Conclusion : In a scotopic condition without accommodation stimuli, spherical aberration is decreased after wearing ASCL, however in the subject have negative spherical aberration spherical aberration could be increased, and which is thought to be the influence of contact lens design and pupil size.

Correlation between Corneal Ablation Amount and Intraocular Pressure after Corneal Refractive Surgery (각막굴절교정수술 후 각막절삭량과 안압변화의 상관관계)

  • Jung, Mi-A;Lee, Eun-Hee
    • The Korean Journal of Vision Science
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    • v.20 no.4
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    • pp.543-551
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    • 2018
  • Purpose : The purposes of this study were to evaluate the changes of intraocular pressure according to corneal ablation amount after corneal refractive surgery and the changes of intraocular pressure according to refractive errors before corneal refractive surgery. Methods : The mean age of adults who underwent LASIK corneal refractive surgery were $37.34{\pm}7.42years$, and 108 adults(48 males, 60 females) were participated in this study. Refractive errors, intraocular pressure, and corneal ablation amount were measured using an autorefractor, a noncontact tonometer, and an excimer laser. All test values were considered statistically significant when p<0.05. Results : The mean intraocular pressure before corneal refractive surgery was $15.08{\pm}2.60mmHg$ in males and $14.16{\pm}2.67mmHg$ in females. The decrease of intraocular pressure after corneal refractive surgery were 4.22mmHg in males and 3.61mmHg in females. Spherical equivalent power were $-3.89{\pm}2.17D$ in males and $-4.45{\pm}2.92D$ in females before corneal refractive surgery, and $-0.10{\pm}0.46D$ in males and $-0.04{\pm}0.46D$ in females after corneal refractive surgery. The corneal ablation amount after corneal refractive surgery were statistically significant, with $53.95{\mu}m$ in males and $61.26{\mu}m$ in females. There was significant correlation between corneal ablation amount and decrease of intaocluar pressure(r=0.2299, p<0.001). As the growth of corneal ablation amount in males, the decrease of intraocular pressure was significantly increased. As the growth of refractive error, the amount of decrease in intraocular pressure was also significant. The decrease of intraocualr pressure were $3.04{\pm}2.18mmHg$ in low refractive error, $4.10{\pm}2.16mmHg$ in middle refractive error, and $4.65{\pm}3.29mmHg$ in high refractive error. Conclusion : We found that intraocular pressure decreased after corneal refractive surgery by noncontact tonometer and the change of intraocular pressure which is an important index for glaucoma diagnosis, may affect the judgment of eye disease. We think that a preliminary questionnaire whether corneal refractive surgery is necessary for the measurement of intraocular pressure.

Assessing and Mapping the Aesthetic Value of Bukhansan National Park Using Geotagged Images (지오태그 이미지를 활용한 북한산국립공원의 경관미 평가 및 맵핑)

  • Kim, Jee-Young;Son, Yong-Hoon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.49 no.4
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    • pp.64-73
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    • 2021
  • The purpose of this study is to present a method to assess the landscape aesthetic value of Bukhansan National Park using geotagged images that have been shared on social media sites. The method presented in this study consisted mainly of collecting geotagged image data, identifying landscape images, and analyzing the cumulative visibility by applying a target probability index. Ramblr is an application that supports outdoor activities with many users in Korea, from which a total of 110,954 geotagged images for Bukhansan National Park were collected and used to assess the landscape aesthetics. The collected geotagged images were interpreted using the Google Vision API, and were subsequently were divided into 11 landscape image types and 9 non-landscape image types through cluster analysis. As a result of analyzing the landscape types of Bukhansan National Park based on the extracted landscape images, landscape types related to topographical characteristics, such as peaks and mountain ranges, accounted for the largest portion, and forest landscapes, foliage landscapes, and waterscapes were also commonly found as major landscape types. In the derived landscape aesthetic value map, the higher the elevation and slope, the higher the overall landscape aesthetic value, according to the proportion and characteristics of these major landscape types. However, high landscape aesthetic values were also confirmed in some areas of lowlands with gentle slopes. In addition, the Bukhansan area was evaluated to have higher landscape aesthetics than the Dobongsan area. Despite the high elevation and slope, the Dobongsan area had a relatively low landscape aesthetic value. This shows that the aesthetic value of the landscape is strongly related not only to the physical environment but also to the recreational activities of visitors who are viewing the scenery. In this way, the landscape aesthetics assessment using the cumulative visibility of geotagged images is expected to be useful for planning and managing the landscape of Bukhansan National Park in the future, through allowing the geographical understanding of the landscape values based on people's perceptions and the identification of the regional deviations.

Evaluation of Applicability of Webtoon Content for Visual Function Education and Consultation for the General Public (일반인을 위한 시각기능 교육 및 상담용 웹툰 콘텐츠의 적용 가능성 평가)

  • Chang Won Park;Hyojin Won
    • Journal of Industrial Convergence
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    • v.22 no.6
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    • pp.99-106
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    • 2024
  • The author thought about how to explain visual functions in an easy-to-understand way to customers visiting the optical shops and provide easy customer consultation, and attempted to evaluate the usability and value of the educational webtoon for patient consultation by applying it to the optical shops's visitors. Survey study was conducted targeting 152 customers who visited optical shops A in Incheon from January to December 2023. In this study, consultation was conducted using educational webtoons to help the general public understand concepts that are difficult to understand, such as binocular vision function, the concept of heterophoria, prism lenses, and binocular balance. The areas of 'understanding', 'interest', 'usability', 'necessity', and 'expression of expertise' felt by the visitors who received counseling were scored and evaluated, and differences according to counseling method were evaluated using an independent sample t-test. Statistical verification was performed. When the optometrist only explained verbally, the score distribution was relatively low: 1.96 points for understanding, 2.06 points for interest, 2.96 points for usability, 4.20 points for necessity, and 3.19 points for expertise. When the optometrist provided explanations along with the book, understanding was 4.14 points, interest was 3.28 points, usability was 3.60 points, necessity was 4.17 points, and expertise was 3.55 points. When the optometrist explained with a webtoon, understanding was 4.57 points, interest was 4.96 points, usability was 4.18 points, necessity was 4.65 points, and expertise was 3.15 points. When explanations were given only verbally, all items showed the lowest scores, whereas consultations using webtoons showed 4 points or more (excellent) in all items except the 'expression of expertise' item. It is evaluated that actively using webtoons in various consultation situations that occur in optical shops will help increase customer interest and concentration.

Analysis of the Eyeglasses Supply System for Ametropes in ROK Military (한국군 비정시자용 안경의 보급체계 분석)

  • Jin, Yong-Gab;Koo, Bon-Yeop;Lee, Woo-Chul;Yoon, Moon-Soo;Park, Jin-Tae;Lee, Hang-Seok;Lee, Kyo-Eun;Leem, Hyun-Sung;Jang, Jae-Young;Mah, Ki-Choong
    • The Korean Journal of Vision Science
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    • v.20 no.4
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    • pp.579-588
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    • 2018
  • Purpose : To analyze the eyeglasses supply system for ametropic soldiers in ROK military. Methods : We investigated and analyzed the supply system of eyeglasses for the ametropic soldiers provided by the Korean military. The refractive powers and corrected visual acuity were measured for 37 ametropic soldiers who wear insert glasses for ballistic protective and gas-masks supplied by the military based on their habitual prescriptions. Full correction of refractive error was prescribed for subjects having less than 1.0 of distance visual acuity, and comparison was held for inspecting the changes in corrected visual acuity. Suggestions were provided for solving the issues regarding current supplying system, and this study investigated the applicabilities for utilizing professional optometric manpower. Results : The new glasses supplied by army for ametropic soldiers were duplicated from the glasses they worn when entering the army. The spherical equivalent refractive powers of the conventional, ballistic protective and gas-mask insert glasses supplied for 37 ametropic soldiers were $-3.47{\pm}1.69D$, $-3.52{\pm}1.66D$ and $-3.55{\pm}1.63D$, respectively, and the spherical equivalent refractive power of full corrected glasses was $-3.79{\pm}1.66D$, which showed a significant difference(p<0.05). The distant corrected visual acuity measured at high and low contrast(logMAR) of conventional, ballistic protective and gas-mask insert glasses were $0.06{\pm}0.80$, $0.21{\pm}0.82$, $0.15{\pm}0.74$, $0.34{\pm}0.89$, $0.10{\pm}0.70$ and $0.22{\pm}0.27$, respectively, while the corrected visual acuity by full corrected glasses were increased to $0.02{\pm}1.05$, $0.10{\pm}0.07$, $0.09{\pm}0.92$, $0.26{\pm}0.10$, $0.04{\pm}1.00$ and $0.19{\pm}1.00$, respectively. There was a significant difference(p<0.05) except for the case of the low contrast corrected visual acuity of the conventional and gas-mask insert glasses. The procedure for ordering, dispensing, and supplying military glasses consists of 5 steps, and it was found that approximately two weeks or more are required to supply from the initial examination. Conclusion : The procedure of supplying the military glasses showed three issues: 1) a lack of refraction for prescription system, 2) relatively long length of time required for supplying the glasses, 3) an inaccurate power of supplied glasses. In order to solve those issues, in the short term, education is necessarily required for soldiers on the measurement of the refractive powers, and in the near future, further standard procedures for prescription of glasses as well as the securement of optometric manpower are expected.

A Study on the Aviation Safety Policy and Enhancement of Aviation Safety for Low Cost Carriers in Korea (한국의 저비용항공사 안전 향상을 위한 안전정책 연구)

  • Lee, Kang-Seok
    • The Korean Journal of Air & Space Law and Policy
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    • v.24 no.2
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    • pp.69-104
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    • 2009
  • This study is to know the Enhancement of Aviation Safety for Low Cost Carrier in Korea through the long and mid term air safety policy. Especially, the aviation safety authorities of the developed countries in aviation establish action plans under the system plan of central government. Then the countries implement those plans systematically to the related aviation business so that they promote efficient air safety policy implementation. At this time, the Korean government should present the vision about an air safety and systematic strategic plan to cope with the future aviation industry change. Also, it is needed to establish a specific aviation safety action plan. Namely, an air safety master plan and long-term road map must be established. This paper deduces some implications through the abroad cases of aviation safety plan, and then tries to find the applying method of the implications to Korea in the rapidly changing aviation market in the 21st century. It is expected that this paper will help the Korean aviation industry to play a major role in the future. In oder to get suggestions aviation policies of advanced countries with regard to aviation safety, we have looked at the aviation policies of the U.S., the U.K., Australia and Japan, and also LCC's states overseas, LCC's safety policies in Korea, and aviation safety status. Since existing LCCs and new LCCs based in Korea have become the new concept, this new market for LCC has been booming recently. Around Southeast Asia, while there are some LCCs including Air Asia which is supported by the government of Malaysia with emphasis on safety, there are other LCCs, which have failed to achieve confidence in safety and have led to aircraft accidents and financial mismanagement, so we need to verify the safety of overseas LCCs, try to improve domestic LCCs in order to fly international routes and aid international aviation safety. LCCs have been increasing lately thanks to open skies policy and a wide variety of flights.lines. Air Busan, Jin Air, Jeju air, Eastar Air are in service. so the risk of new potential hazards may increase. Therefore it is necessary to take the initiative in aviation markets inside and outside of Korea and the safety management of new LCCs should be taken more seriously than ever before. Among overseas aviation safety policies, we need to implement the FAA's Filght Plan which has a specific Business Plan. I hope this thesis will help improve aviation safety locally and internationally.

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Suggestion of Similarity-Based Representative Odor for Video Reality (영상실감을 위한 유사성 기반 대표냄새 사용의 제안)

  • Lee, Guk-Hee;Choi, Ji Hoon;Ahn, Chung Hyun;Li, Hyung-Chul O.;Kim, ShinWoo
    • Science of Emotion and Sensibility
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    • v.17 no.1
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    • pp.39-52
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    • 2014
  • Use of vision and audition for video reality has made much advancement. However use of olfaction, which is effective in inducing emotion, has not yet been realized due to technical limitations and lack of basic research. In particular it is difficult to fabricate many odors required for each different video. One way to resolve this is to discover clusters of odors of similar smell and to use representative odor for each cluster. This research explored clusters of odors based on pairwise similarity ratings. 300 diverse odors were first collected and sorted them into 11 categories. We selected 152 odors based on their frequency, preference, and concreteness. Participants rated similarity on 1,018 pairs of odors from selected odors and the results were analyzed using multi-dimensional scaling (MDS). Based on the idea that low odor concreteness would support valid use of representative odor, the MDS results are presented from low to high smell concreteness. First, flowers, plants, fruits, and vegetables was classified under the easy categories to use representative odor due to their low smell concreteness (Figure 1). Second, chemicals, personal cares, physiological odors, and ordinary places was classified under the careful categories of using it due to their intermediate concreteness (Figure 2). Finally, food ingredients, beverages, and foods was classified under the difficult categories to use it because of their high concreteness (Figure 3). The results of this research will contribute to reduction of cost and time in odor production and provision of realistic media service to customers at reasonable price.

Person Identification based on Clothing Feature (의상 특징 기반의 동일인 식별)

  • Choi, Yoo-Joo;Park, Sun-Mi;Cho, We-Duke;Kim, Ku-Jin
    • Journal of the Korea Computer Graphics Society
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    • v.16 no.1
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    • pp.1-7
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    • 2010
  • With the widespread use of vision-based surveillance systems, the capability for person identification is now an essential component. However, the CCTV cameras used in surveillance systems tend to produce relatively low-resolution images, making it difficult to use face recognition techniques for person identification. Therefore, an algorithm is proposed for person identification in CCTV camera images based on the clothing. Whenever a person is authenticated at the main entrance of a building, the clothing feature of that person is extracted and added to the database. Using a given image, the clothing area is detected using background subtraction and skin color detection techniques. The clothing feature vector is then composed of textural and color features of the clothing region, where the textural feature is extracted based on a local edge histogram, while the color feature is extracted using octree-based quantization of a color map. When given a query image, the person can then be identified by finding the most similar clothing feature from the database, where the Euclidean distance is used as the similarity measure. Experimental results show an 80% success rate for person identification with the proposed algorithm, and only a 43% success rate when using face recognition.

Effect of Life Stress and Anger Expression in College Students on Suicidal Ideation (대학생의 생활스트레스, 분노표현이 자살생각에 미치는 융복합적 영향)

  • Chin, Eun-Young;So, Sung-Sup;Lee, Myung-In
    • Journal of Digital Convergence
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    • v.13 no.8
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    • pp.409-418
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    • 2015
  • The study was conducted to identify the effects of life stress and anger expression in college students on suicidal ideation. In order to get the data by self-report questionnaires, 219 subject were selected from 14th of November to 6th of December, 2014. The collected data were analyzed using SPSS/Win 18.0 and descriptive statistics, t-test, one-way ANOVA, Pearson correlation coefficient, and hierarchical regression analysis. The findings reveal that suicidal ideation of college students was low which is average score $5.74{\pm}6.38$(possible range 0~38). This study determined that suicidal ideation is positive correlated with life stress and anger expression(anger-out, anger-in). The extent of anger-out, anger-in, family relationship and major satisfaction was a significant predictor of suicidal ideation and accounted for 24% of the explanation of suicidal ideation of college students. Base on the outcomes of this study, designing an intervention program that emphasizes stress and anger management in order to decrease suicidal ideation.

Edge Grouping and Contour Detection by Delaunary Triangulation (Delaunary 삼각화에 의한 그룹화 및 외형 탐지)

  • Lee, Sang-Hyun;Jung, Byeong-Soo;Jeong, Je-Pyong;Kim, Jung-Rok;Moon, Kyung-li
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.1
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    • pp.135-142
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    • 2013
  • Contour detection is important for many computer vision applications, such as shape discrimination and object recognition. In many cases, local luminance changes turn out to be stronger in textured areas than on object contours. Therefore, local edge features, which only look at a small neighborhood of each pixel, cannot be reliable indicators of the presence of a contour, and some global analysis is needed. The novelty of this operator is that dilation is limited to Deluanary triangular. An efficient implementation is presented. The grouping algorithm is then embedded in a multi-threshold contour detector. At each threshold level, small groups of edges are removed, and contours are completed by means of a generalized reconstruction from markers. Both qualitative and quantitative comparison with existing approaches prove the superiority of the proposed contour detector in terms of larger amount of suppressed texture and more effective detection of low-contrast contour.