• Title/Summary/Keyword: Optics problem

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Analysis on the Characteristics of National Assessment of Educational Achievement (NAEA) Items for Science Subject: With a Focus on Optics (국가수준 학업성취도 평가의 과학 문항 특성 분석 : 광학 내용을 중심으로)

  • Lee, Bongwoo;Lee, Inho
    • Journal of The Korean Association For Science Education
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    • v.35 no.3
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    • pp.465-475
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    • 2015
  • The purpose of this study is to analyze the results of physics (optics) in nationwide standardized assessment and to investigate middle-school students' characteristics of achievement by using an option response rate distribution curve. For this purpose, we analyzed the 10 optics problems from the National Assessment of Educational Achievement (NAEA) items for middle school science subject conducted in 2010-2013. The results of this study are as follows; First, students showed a little higher achievement in optics than classical mechanics and electromagnetism. Second, students achieved significantly worse in 'formation of image' in 'light' part and 'variation of phase in propagation of wave' in 'wave' part. Third, students showed a context-dependent problem solving strategy and result. Additionally, we suggested some implications about the readjustment of some optics concepts level of national science curriculum, the need for teaching and learning strategies for basic level students, and the need for teaching and learning strategies focused on the realistic context.

Contact lens Prescription and Satisfaction with Astigmatism Eye (난시안의 콘택트렌즈 처방과 만족도에 관한 연구)

  • Kim, Mi-Yeon;Kim, Yeong-Mi;Kim, Tae-Hun;Sung, A-Young
    • Journal of Korean Ophthalmic Optics Society
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    • v.11 no.4
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    • pp.317-322
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    • 2006
  • For this study we made up a question investigation to analyze a grade of satisfaction and a side effect about the prescription actual condition of contact lens of person with astigmatism among the person who has a error of refraction. The whole patient of refractive error was 46 person, there were 11 person who only wear spectacles by correction of visual acuity among person to a question investigation and 35 person who only wear contact lens. Under investigation 35 person who only wear contact lens, there were 25 person who experience the problem which occurs because of contact lens wearing for a long time. The most patient who made up a question investigation very choose remainder item except for item of very satisfaction. The their reason that could not satisfaction was non corrected astigmatism, wrong prescription, wrong Base curve, out of life span etc.

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How Many Korean Science High-school Students Find the Same Scientific Problem as Kepler Found in Optics and Physiology? (얼마나 많은 과학고등학교 학생들이 케플러가 광학과 생리학에서 발견한 과학적 문제를 발견하는가?)

  • Kim, Young-Min
    • Journal of Gifted/Talented Education
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    • v.21 no.2
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    • pp.575-589
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    • 2011
  • The aims of this study are to investigate how Kepler found a scientific problem for the retinal image theory and to investigate how the science high-school students respond when the same situation is applied to them. And their results was compared with general high-school students' results. Kepler found the scientific problem in the eye vision through the critical analysis of contemporary theories of vision, based on his relevant knowledge of optics. When we applied the same situation to the Korean science high school and general high-school students, only a few of science high-school students found the scientific problem as same as Kepler's finding. From the results, it is suggested that in development of creativity teaching material, the situations like Kepler's problem finding need to be included in the programs.

Color Vision Abnormality of Elementary School Students in Kwang Ju Area (광주지역 초등학생들의 색각이상에 관한 연구)

  • Ryu, Geun-Chang;Yoon, Young;Seong, Jeong-Sub
    • Journal of Korean Ophthalmic Optics Society
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    • v.12 no.3
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    • pp.89-91
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    • 2007
  • Color vision test was conducted to elementary school students at age of 9 to 13, with total subject number of 598 which live in Gwang Ju area. 325 (54.3%) boys and 273 (45.7%) girls were subjected using Hahn Color Vision test to find out color recognition problems. 1. Ratios of color vision abnomality were 6.25% in 9 year old students, 9.2% in 10 year old students, 8.4% in 12 year old students, 7.8% in 13 year old students, which means 7.9% of the total 598 subjects had color recognition matters. 2. Red-Green dyschromatopsia was 7.8% of the total 598 subjects which includes most of subjects. None of them had green-yellow recognition problem. Full dyschromatopsia had frequency of 0.2%. 3. 10.7% of boys had color vision abnormality, while 10.7% of girls had color vision abnormality, which means that boys have color recognition problems with higher rate than girls.

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Development of Gas-mask Spectacles (방독면 안경 개발)

  • Lee, Jeung-Young;Parkm Jeong-Sik;Jang, Woo-Yeong
    • Journal of Korean Ophthalmic Optics Society
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    • v.13 no.4
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    • pp.9-12
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    • 2008
  • Purpose: Current gas-mask is very uncomfortable structure for spectacles wearer. Improving this problem can aid military men and firemen to protect themselves and rescue other person. Methods: we changed the structure from dual type of outward lens and inward lens into a single type structure. we attached acrylic frame to gas-mask instead of outward lens and protected the gas inflow by shutting the gab of lens and frame using silicon shield, and made the frame "S" style for removing astigmatism and maintaining of vertex distance. Results: It was possible to correct visual acuity and gas shield, and could changed the lens like a common spectacles. The new type of gas-mask spectacles could remove 0.53D~1.78D astigmatism occurred from the slant of eyesight and lens surface, 0.07D~0.66D overcorrection occurred from short vertex distance, and 0.1D~0.3D astigmatism occurred from pantoscopic angle. Conclusion: Because new type of gas-mask spectacles had clear visual field, it was expected to improve fighting power and rescue ability.

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Integrated Optimization Design of Carbon Fiber Composite Framework for Small Lightweight Space Camera

  • Yang, Shuai;Sha, Wei;Chen, Changzheng;Zhang, Xingxiang;Ren, Jianyue
    • Journal of the Optical Society of Korea
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    • v.20 no.3
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    • pp.389-395
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    • 2016
  • A Carbon Fiber Composite (CFC) framework was designed for a small lightweight space camera. According to the distribution characteristics of each optical element in the optical system, CFC (M40J) was chosen to accomplish the design of the framework. TC4 embedded parts were used to solve the low accuracy of the CFC framework interface problem. An integrated optimization method and the optimization strategy which combined a genetic global optimization algorithm with a downhill simplex local optimization algorithm were adopted to optimize the structure parameters of the framework. After optimization, the total weight of the CFC framework and the TC4 embedded parts is 15.6 kg, accounting for only 18.4% that of the camera. The first order frequency of the camera reaches 104.8 Hz. Finally, a mechanical environment test was performed, and the result demonstrates that the first order frequency of the camera is 102 Hz, which is consistent with the simulation result. It further verifies the rationality and correctness of the optimization result. The integrated optimization method mentioned in this paper can be applied to the structure design of other space cameras, which can greatly improve the structure design efficiency.

An inquiry into Institutionalization of Eye-Examiner in Korean Ophthalmic Clinics - Focusing on a Survey of Orthoptist Systems in Japan and English-Speaking World - (한국 안과병원의 검안전담인력 제도화에 관한 고찰 - 일본의 시능훈련사 제도와 영어권 국가의 Orthoptist 제도에 대한 조사를 중심으로 -)

  • Lee, Hyun Min;Jung, Seok Hun;Kim, Dal-Young
    • Journal of Korean Ophthalmic Optics Society
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    • v.14 no.1
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    • pp.87-95
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    • 2009
  • Purpose: The aim of this study is to reveal necessity of orthoptist system in Korea, by comparative analysis between the orthoptist system of developed countries and the present condition in Korean ophthalmic clinics. Methods: Choosing 4 developed countries, we surveyed their education systems, license requirements and process, and service coverage. An inquiry into desirable Korean orthoptist system was added on the basis of the comparative survey. Results: The developed countries have systems in which professional orthoptists, who have got their licenses after official education, do the eye examination under the supervision of ophthalmologists. On the other hand in Korea, a problem is revealed that opticians play a role of eye-examiner in the ophthalmic clinics without any institutional support. Conclusions: The legalistic basis is quite needed in Korea that permit optometry graduates to be eye-examiners in the ophthalmic clinics, by introducing the orthoptist system.

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Effect of the Phase and Amplitude for Optical Visual Encryption (광시각 암호화에 위상과 진폭이 미치는 영향)

  • 이석기;류충상;구향옥;오창석
    • The Journal of the Korea Contents Association
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    • v.1 no.1
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    • pp.74-82
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    • 2001
  • Visual cryptography made it possible to decrypt the Information encrypted by thresholding scheme not with digital system but with human vision system. This method, however, has some limit in it because of the rack of resolution in both the spatial and amplitude domain. Optical visual cryptography, which used laser system instead of human eyesight, was proposed by conjunction of the optical theory with the cryptography. However, it also had some difficulties because it did not overcome the existing problem of visual cryptography completely. The problem occurred in the process of transferring data processing system from visual to optics. Therefore, it is appropriate to approach these problems in terms of optics. In this paper, we analysis, in the aspect of frequency, the security characteristics and the noise level occurred in the process of optical visual encryption.

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Near-field Sonar Cross Section Analysis of Underwater Target Using Spherical Projection Method (구면투영법을 이용한 수중표적의 근거리장 소나단면적 해석)

  • Kim, Kook-Hyun;Cho, Dae-Seung
    • Journal of the Society of Naval Architects of Korea
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    • v.45 no.6
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    • pp.695-702
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    • 2008
  • In this paper, a new numerical method is proposed to analyze near-field sonar cross section of acoustically large-sized underwater targets such as submarines. A near-field problem is converted to a far-field problem using a spherical projection method with respect to the objective target. Then, sonar cross section is calculated with a physical optics well established in far-field acoustic wave scattering problems. The analysis results of a square flat plate compared with those obtained by other method show the accuracy of the proposed method. Moreover, it is noted that the sonar cross section is varied with respect to the targeting point as well as the range. Finally, numerical analysis results of real-like underwater target such as a submarine pressure hull are discussed.

A Study on Improvement and Problem of Ready-made Reading Spectacles (상품화된 근용안경의 문제점 및 개선 방안에 관한 연구)

  • Lee, Hark Jun
    • Journal of Korean Ophthalmic Optics Society
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    • v.1 no.1
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    • pp.85-91
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    • 1996
  • This is a study of the measurement of inter papillary constance (P.D) in 702 old aged farmers (aged over 45) and the comparision of frame size and distance space of optical center (O.C) from 240 Ready-made Reading spectacles. The average of P.D in male (62.83mm) is greater than in female (61.18mm), and the O.C of Ready-made Reading spectacles of Plastic lens (71.2mm) longer than glass lens (70.8mm). The correction prism power by wearing Reading spectacles in male was 0.7prism to 3.6prism and in female was 0.9prism to 4.4prism. So the prism power in female is greater than in male.

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