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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.

Comparison of Stereopsis by Influence Factors in Induced Aniseikonia (유발 부등상시에서 영향인자에 따른 입체시의 비교)

  • Jung, Su A;Kim, Hyun Jung
    • Journal of Korean Ophthalmic Optics Society
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    • v.18 no.4
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    • pp.465-471
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    • 2013
  • Purpose: This study was conducted to research effects of influence factors on stereopsis of induced aniseikonia in emmetropia. Methods: 20 college students (a mean age of $22.50{\pm}2.72$ years, 14 males, 6 females) were selected as subjects and all of them had no ocular disease or systemic disease, the refractive correction of spherical equivalent within ${\pm}0.50$ D, the corrected visual acuity of 1.0 or better and the aniseikonia values less than 1% by AWAYA. Subject's dominant eye was checked by Hole in card method and contact lenses of -7.00 ~ +7.00D were fitted to cause anisometropia in dominant eye or non-dominant eye, respectively. And then aniseikonia was induced with spectacles to correct refractive error by contact lenses. Stereopsis was measured by Random Dot Stereo Acuity Test with LEA symbols$^{(R)}$ (Vision Assessment Corporation$^{TM}$, USA). Results: Stereopsis was remarkably reduced by inducing aniseikonia, with induced aniseikonia in dominant eye, with higher diopter of wearing contact lenses to induce anisometropia, with spectacles lenses correction of minus power after fitting contact lenses with plus power and in case of men. Conclusions: It should be considered to correct anisometropia that aniseikonia could cause reduction of stereopsis.

Correlation of Refractive Error, Axial Length, Chamber Depth, Lens Thickness and Corneal Thickness of Normal University Students (정상 대학생의 눈 굴절이상, 안축장, 전방깊이, 수정체두께 그리고 각막두께의 연관성)

  • Kim, Chang-Sik;Lee, Hak-Jun
    • Journal of Korean Ophthalmic Optics Society
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    • v.13 no.1
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    • pp.89-94
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    • 2008
  • Purpose: To make a comparative study of correlation between biometry data of size in eyeball and refractive error. Methods: The subjects were 68 normal university students (male 36, female 32) and the average age was 22.85${\pm}$3.12. We measured the students' eyesight by A-scan ultrasound and refractor. The results were examined it's statistical significance by SPSS 12.0 version. Results: The mean of axial length was 24.31${\pm}$1.24 mm, chamber depth was 3.48${\pm}$0.28 mm, lens thickness was 3.56${\pm}$0.26 mm and corneal thickness was 0.55${\pm}$0.03 mm. Male's Axial length and chamber depth were larger than female's. As reflective error decreases the thickness of lens become thicker. The measurement data between right eye and left eye didn't had difference and there was no correlation with result of T-test. There were statistically significant correlation with length and chamber depth, axial length and corneal thickness, chamber depth and corneal thickness, and refractive error and lens thickness (p<0.01). Refractive error and axial length were minus linear regression (r=-0.56). Conclusions: Eye's refractive error was changed by axial length, chamber depth and lens thickness but it wasn't related with sex and whether it is a right eye or a left eye.

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Subjective Visuoperception to Vertical Yoked Prisms (수직동향프리즘의 자각적 시감각에 관한 연구)

  • Kim, Jae-Do;Kim, Dae-Hyun;Lee, Ik-Han;Kim, Bong-Whan;Kim, Young-Hoon
    • Journal of Korean Ophthalmic Optics Society
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    • v.13 no.1
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    • pp.95-99
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    • 2008
  • Purpose: Even refractive error is perfectly corrected by glasses power, the glasses wearer can feel imbalance and uncomfortable by prism effects. The purpose of this study was to investigate subjective imbalance to vertical yoked prism in visually normal subjects. Methods: Visually normal 37 subjects (aged 20 to 31 y) were fully corrected by soft contact lens and worn vertical yoked prism, base up and base down 1, 2, 4, 6, 8 prism diopter(pd) at random order. A rating scale questionnaire was administered to assess quantitatively subjective imbalance to the yoked prism. The near phoria tests were done using Howell-Kim phoria card at 40 cm distance. Results: For the subjective response of imbalance, base up yoked prism was higher than base down yoked prism (t-test: t=4.67, p=0.00) in over 2 prism diopters. The frequency of subjects who feel imbalance by base up vertical yoked prism is higher for near esophoric group than for exophoric group. Conclusions: To reduce subjective imbalance caused by glasses such as dizzy, it needs to make the minimum prism effect, and base down yoked prism is more effective than base up yoked prism in prism effects.

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A Study on the quantitative measurement methods of MRTD and prediction of detection distance for Infrared surveillance equipments in military (군용 열영상장비 최소분해가능온도차의 정량적 측정 방법 및 탐지거리 예측에 관한 연구)

  • Jung, Yeong-Tak;Lim, Jae-Seong;Lee, Ji-Hyeok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.5
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    • pp.557-564
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    • 2017
  • The purpose of the thermal imaging observation device mounted on the K's tank in the Republic of Korea military is to convert infrared rays into visual information to provide information about the environment under conditions of restricted visibility. Among the various performance indicators of thermal observation devices, such as the view, magnification, resolution, MTF, NETD, and Minimum Resolvable Temperature Difference (MRTD), the MRTD is the most important, because it can indicate both the spatial frequency and temperature resolvable. However, the standard method of measuring the MRTD in NATO contains many subjective factors. As the measurement result can vary depending on subjective factors such as the human eye, metal condition and measurement conditions, the MRTD obtained is not stable. In this study, these qualitative MRTD measurement systems are converted into quantitative indicators based on a gray scale using imaging processing. By converting the average of the gray scale differences of the black and white images into the MRTD, the mean values can be used to determine whether the performance requirements required by the defense specification are met. The (mean) value can also be used to discriminate between detection, recognition and identification and the detectable distance of the thermal equipment can be analyzed under various environmental conditions, such as altostratus, heavy rain and fog.

A Case Study on the Visually Impaired Secondary Students' Conception of the Changes of State of Water (시각장애 중고등학생의 물의 상태변화 개념에 대한 사례 연구)

  • Kim, Hak Bum;Cha, Jeongho
    • Journal of the Korean Chemical Society
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    • v.62 no.1
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    • pp.43-51
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    • 2018
  • In this study, visually impaired secondary students' conception of "changes of state of water" was explored. Science inquiry activity for students with visual impairments was implemented to 16 middle school students and 15 high school students from school for the blind. 14 of them were totally blind, 13 had low vision and the others were not identified. Inquiry activities were conducted by communicating with the researcher while students were individually exploring the molecular models of water and ice developed for the study. After the exploration, students were asked to explain the concept of changes of state of water with the model they explored. Opinion on the need and the usability of this kind of tactile model was also asked to them. All conversations were recorded, transcribed, and analyzed. As a result, students with visual impairments answered exactly about the materials used for the model and their numbers. However, they didn't know what the model stood for. They had experiences of learning molecule of water and changes of state of water, but it was a phenomenon and superficial understanding. Students got to understand the molecular structures of water and ice, and had a positive perception on the need and the usability of the model. Based on these results, educational implications were discussed.

A study on the spectacles-wearing and eyesight health behavior of the middle school students (서울시내 일부 중학생의 시력 및 안경착용과 그에 따른 보건행태 조사연구)

  • Jeon, Ye-Jin;Kim, Myung
    • Korean Journal of Health Education and Promotion
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    • v.11 no.2
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    • pp.87-106
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    • 1994
  • Owing to the use of many cultural facilities, the elevation of life standards and the high level progress of industry, visual impairment was on increasing trends. Especially due to studying for many hours, the myopia of adolescents became a serious social issue. The purpose of this study was to understand adolescent's wearing glasses and eyesight condition, whether the primary myopia factor and the subjective symptoms were different between the myopia group and the normal group, between the wearing glasses group and the non-wearing glasses group, and the effect on physical, mental and study activity of myopia. The subject of investigation was 627 middle school students in Seoul and the investigation was accomplished from July 7th, 1993 to July 12th, 1993. The data were analyzed by the percentage, x²-test, t-test and ANOVA of SPSS. The results were as followed; 1. The rate of the right and left eyesights higher than 0.8 in the normal group was 47.0%, and those less than 0.7 in the myopia group was 53.0%. In the boy students, the normal group was 54.1%, the myopia group was 45.9%. In the girl students, the normal group was 39.2%, the myopia group was 60.8%. Therefore the girl students' myopia rates were higher than the boy students', and this result was significant(p<0.01). 2. The rate of wearing glasses of the middle school students was 44.6%. The rate of wearing glasses of the girl students was 56.8%. The rate of wearing glasses of the girl students was higher than that of the boy students 43.2%. The rate of necessary glasses of the middle school students was 6.1% and the rate of necessary glasses of the boy students was 7.9%, the rate of necessary glasses of the girl students was 4.1%. 3. In case of a family member of the student wear glasses, the rate of wearing glasses was higher. 4. In the myopia group, the main reason for not wearing glasses was "Uncomfortable"(63.3% in the boy students, 40% in the girl students). In case of the girl students, "Nonpermission of their parents" was 18.7% and remarkably higher than 5.1% in case of the boy students. 5. The factor of myopia was that "The bad attitude of watching TV closely" was 19.9%, that "The dimly-lit room" was 6.6%. 6. In order to protect eyesight, the rate of the students who practiced "Looking at something from afar 3∼4times a day" was 37.3%, the rate of the students who did "Eye exercise" was 17.5%, the rate of the students who took "A medicine for promoting nutrition" was 12.9%. The rate of taking the medicine was higher than 3.5% in the normal eyesight group. 7. After near working, the point of subjective symptoms was higher in the myopia group than in the normal group and in the wearing glasses group than in the unwearing group and in the girl students than in the boy students. 8. The longer time to watch TV, the higher point of subjective symptoms. The longer distance to watch TV, the lower point of subjective symptoms(p<0.05).

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Health Status of Vulnerable Preschool Children and Their Mothers' Health Management (취약계층 학령전기 아동의 건강상태와 어머니의 아동 건강관리실태)

  • Kang, Young-Sil;Kwon, In-Soo
    • Child Health Nursing Research
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    • v.19 no.3
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    • pp.159-167
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    • 2013
  • Purpose: The purpose of this study is to find out preschool children's health status and their mothers' health management in the vulnerable classes. Methods: The assessment tool was developed, taken into consideration existing studies, materials produced by the customized visiting health care system, and review of visiting nurses of health centers and related experts. Data were collected January to February 2010 from 259 mothers by visiting nurses, and analyzed using SAS program for descriptive statistics. Results: Body weight less than 3 percentile was found for 5.0% children and over 97 percentile for 7.7%. Atopy was found in 17.8% children, no hand-washing after toileting and before meal in 30.9% and 36.7% respectively, no breakfast in 15.8%, and irregular meal in 32.0%. Sex education was made by 45.7% mothers, regular dental check by 56.6%, and hearing and eyesight test by 61.1% and 66.8% respectively. Home environment for upbringing is 34.3 in the scale of 41, and accident prevention 17.5 in the scale of 22. Conclusion: It is necessary to make an intervention on children's weight, personal sanitation and meal time in the vulnerable classes. Mothers need to be educated for appropriate health care, and home environments to improve upbringing and accident prevention.

병원에서의 산업보건관리

  • Jeon, Gyeong-Ja
    • Korean Journal of Occupational Health Nursing
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    • v.2
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    • pp.40-51
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    • 1992
  • 본 연구는 병원에서의 산업보건관리 실태를 파악하기 위하여 전국에 있는 병원을 대상으로 1992년 12월 1일부터 1993년 1월 23일까지 설문조사를 설시하였다. 설문조사에 응당한 병원은 41개병원으로 회수율은 51.9%였다. 조사에 이용된 설문지는 산업안전보건법 내용을 기초로 하여 본 연구자가 작성한 것이며 안전보전에 관한 제반 규정, 안전보건관리체계, 근로자건강관리, 작업환경관리, 보건교육, 보건관련시설, 질병 및 상해에 대한 보상 등에 관한 45개문항으로 구성되어 있다. 분석결과는 다음과 같다. 첫째, 전체 병원 중 68.3%가 안전보건관리 규정이 있다고 답하였으며, 77.5%의 병원이 단체협약 중 근로자의 안전과 보건에 관한 조항을 포함시키고 있는 것으로 나타났다. 단체협약에 포함된 내용 중에는 정기건강진단(23.7%)과 질병 및 상해에 대한 보상(20.9%), 안전보건위원회의 구성(18.1%)등이 많았다. 둘째, 대상 병원중 66.7%가 안전보건관리책임자, 관리감독자, 안전담당자를 두고 있는 것으로 나타났고, 근로자수가 1,000명 이상인 병원은 83.3%가 이들 인력을 선임하고 있다. 그러나, 보건관리자와 안전관리자를 전담으로 두고 있는 경우는 한 곳도 없었으며 50%이내에서 겸직으로 선임하고 있었다. 또한, 안전보건위원회를 운영하고 있거나 노사협의회로 이를 대치하고 있는 병원은 54.2%로 절반 수준에 머물렀고, 그나마 정기적으로 운영을 하고 있다고 답한 병원은 3개 병원 밖에 되지 않았다. 세째, 근로자 건강관리를 위한 건강진단 실시 현황을 보면, 채용시검진 97.6%, 일반건강진단 100.0%, 특수 건강진단 24.4%가 실시하고 있었다. 건강진단에서 주로 실시하고 있는 항목은 흉부 X선검사, 시력, 혈압, 혈청GOT/GPT, 체중, 신장등이었다. 그러나, 병원에서 감염될 수 있는 기회가 높은 간염항원/항체검사의 실시율은 85.7%로 아직도 실시하지 않는 병원이 있음을 알 수 있다. 네째, 작업환경관리를 위하여 정기적으로 환경측정을 실시하는 병원은 21.6%였고 주로 측정하는 항목은 방사선이었다. 특히 소음, 조명, 분진에 대한 측정이 이루어지지 않음은 근로자뿐아니라 환자의 안위에도부정적인 영향을 미칠 수 있다. 다섯째, 안전한 작업과 근로자의 건강을 위하여 정기적인 보건교육을 설시하고 있는 병원은 불과 5.6%였다. 교육내용은 주로 안전에 관한 것이었다. 여섯째, 근로자의 일상적인 건강문제를 해결해주는 의무실을 독립적으로 마련하고 있는 병원은 한 곳도 없었고, 교대근무자나 당직자를 위한 수면시설은 44.7%, 작업 후에 사용할 수 있는 샤워시설은 35.1%의 병원이 마련하고 있었다. 일곱째, 근무중 다치거나 병에 걸렸을 때 치료비에 대한 부담은 대체로 병원이 하고 있으며 치료기간 중 근무는 병가나 휴직으로 처리되고 있다. 이는 병원이 산재보상보험법에 적용을 받지 않은 사업으로 분류되어 있는 현실에 기인된 것으로 보상과 관련된 부담을 병원이나 근로자 모두가 안게 되는 결과를 초래하게 되는 것이다. 이상에서 볼 때 병원근로자를 위한 산업보건관리는 주로 건강진단과 질병 및 상해에 대한 보상제도가 이루어지고 있는 실정이다. 그러므로 질병의 예방이나 악화방지 나아가 건강증진을 도모하기 위한 지속적인 노력을 기울이고 있는 병원은 전무한 상태임을 알 수 있다. 이러한 현실을 병원근로자를 위한 산업보건관리에 대한 인식이 전반적으로 부족함을 드러내는 것으로 이를 개선하기 위한 보다 적극적인 노력이 시급히 요청되고 있다.

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APERT SYNDROME : CASE REPORT (Apert syndrome : 증례보고)

  • Park, Kwang-Sun;Park, Ho-Won;Lee, Ju-Hyun;Seo, Hyun-Woo
    • Journal of the korean academy of Pediatric Dentistry
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    • v.35 no.3
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    • pp.539-547
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    • 2008
  • Apert syndrome is an autosomal dominant condition characterized by craniosynostosis, midface hypoplasia, and syndactyly of the hands and feet. It occurs in about 1 of every 65,000 to 160,000 births and is caused by a mutation in the fibroblast growth factor receptor 2(FGFR2) gene. Apert syndrome typically produces acrobrachycephaly(tower skull). The occiput is flattened, and there is a tall appearance to the fore head. Ocular proptosis is a characteristic finding, along with hypertelorism and downward slanting lateral palpebral fissures. The middle third of the face is markedly retruded and hypoplastic, resulting in a relative mandibular prognathism. The reduced size of the nasopharynx and narrowing of the posterior choana can lead to mouth breathing, contributing to an open-mouth apprance. Three fourths of all patients exhibit either a cleft of the soft palate or a bifid uvula. The maxillary hypoplasia leads to a V-shaped arch and crowding of the teeth. A 6-year-old male patient visited to the Department of Pediatric dentistry, Kangnung National University of Dental Hospital. He visited the hospital to get treatment of carious teeth. The purpose of this report is to present a specific dental manifestations about the apert syndrome.

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