• Title/Summary/Keyword: Lens

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Thermographic Assessment in Dry Eye Syndrome, Compared with Normal Eyes by Using Thermography (열화상카메라를 이용한 정상안과 건성안의 서모그래피 비교)

  • Park, Chang Won;Lee, Ok Jin;Lee, Seung Won
    • Journal of Korean Ophthalmic Optics Society
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    • v.20 no.2
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    • pp.247-253
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    • 2015
  • Purpose: The purpose of this study was to compare and analyze the ocular surface and the palpebral conjunctiva of categorized subjects, which were divided into normal eye group and dry eye group, by using a thermal camera. Methods: Subjects were 144 eyes of 72 normal university students, who didn't have any corneal disease, abnormal lacrimal ducts, medical records regarding ocular surgeries, or experience of using contact lens. Subjects were divided into two groups, which were normal eye group and dry eye group, based on the results of TBUT, Schirmer I test, and McMonnies test. After categorizing the subjects, the temperature of the subjects' ocular surface and the palpebral conjunctiva were measured and analyzed by using a thermal camera (Cox CX series, Answer co., Korea). Results: In the normal eye group's Central Ar.1, Nasal Ar.2, Temporal Ar.3, Superior Ar.4, Inferior Ar.5, the measured amount of temperature change on each area was $-0.13{\pm}0.08$, $-0.14{\pm}0.08$, $-0.12{\pm}0.08$, $-0.14{\pm}0.08$, $-0.10{\pm}0.09(^{\circ}C/sec)$. The dry eye group's results were $-0.17{\pm}0.08$, $-0.16{\pm}0.07$, $-0.16{\pm}0.08$, $-0.17{\pm}0.09$, $-0.15{\pm}0.08(^{\circ}C/sec)$. When compared with the normal eye group, the values of Ar.1, Ar.3, Ar.5 were significantly different in the dry eye group(p<0.05). The amount of temperature change, which was observed on the palpebral conjunctiva(Ar.1:central, Ar.2: nasal, Ar.3: temporal) of the normal eyes, measured by thermography, was $34.36{\pm}1.12$, $34.17{\pm}1.10$, $34.07{\pm}1.12^{\circ}C$ on each area. Same values taken from the dry eye group was $33.55{\pm}0.94$, $33.43{\pm}0.97$, $33.51{\pm}1.06^{\circ}C$ on each area. The values of Ar.1, taken from the dry eye group, had a significant difference, compared to the values of the normal eye group(p=0.05). Conclusion: The temperature of the ocular surface decreased faster on the dry eyes, compared to the normal eyes. The temperature measured on the palpebral conjunctiva of the dry eyes were also lower than the normal eyes. The temperature changes on the ocular surface, observed with a thermal camera, were objective values to assess the stability of tear films, and might provide useful data for studies related to dry eye syndrome.

Induced Prisms of Wearing Glasses Measured by Photographing (사진촬영으로 측정한 착용안경의 유발프리즘)

  • Shin, Hyung-Sup;Jang, Jun-Kyu
    • Journal of Korean Ophthalmic Optics Society
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    • v.19 no.4
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    • pp.527-532
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    • 2014
  • Purpose: The matching of the optical center and the pupil center was measured by photographs in wearing glasses. In this study, the influences of the induced prism by the mismatching are studied. Methods: 74 subjects (148 eyes) who were spectacles wearer were participated in this study. The mean age was $29.19{\pm}12.22$ years (range 19-55 years). The facial photographs of subjects were taken while wearing spectacles. The matching of the corneal reflected image and optical center of the spectacle lens in the horizontal deviations, and the vertical deviations were measured by the observation of the photo image. The prisms induced in accordance with various frame type were calculated from the mismatching deviations. Results: The binocular horizontal deviations were $1.55{\pm}1.70mm$ for the metal frame, $1.71{\pm}2.21mm$ for the clings type plastic frame, and $1.15{\pm}1.38mm$ for the plastic frame. In the horizontal direction induced prism, the ratio over the tolerance was 23%. The ratio were the 17.6% at the BI prism, and 5.4% at the BO prism. The binocular vertical deviation comparisons were $3.93{\pm}1.91mm$ for the metal frame, $5.79{\pm}1.93mm$ for the clings type plastic frame, and 1$6.01{\pm}2.94mm$ for the plastic frame. In the vertical direction induced prism, the ratio over the tolerance was 44.6%. Based on the refraction power, the ratio were 12.2% at -0.25${\leq}-3.00$, and 32.4% at -3.00${\leq}-12.00D$. Conclusions: The induced prisms in the horizontal direction were much in the BI prism. The binocular vertical deviations of the glasses.

Spawning Behavior and Early Life History of Aucha Perch, Coreperca kawamebari from Korea (한국산 꺽저기 (Coreoperca kawamebari)의 산란습성(産卵習性) 및 초기생활사(初期生活史))

  • Han, Kyeong-Ho;Park, Joon-Taek;Kim, Byeong-Mu;Oh, Sung-Hyun;Lee, Sung-Hun;Jin, Dong-Soo
    • Korean Journal of Ichthyology
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    • v.12 no.2
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    • pp.129-136
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    • 2000
  • The aucha perch, Coreoperca kawamebari was collected in Tam-jin river from February to June 1998. It was reared in the laboratory and observed the spawning behavior and early life history. Spawning season was from mid of April to the end of May in the Tam-jin river. The fertilized eggs were demersal of adhesive, transparent and spherical in shape. Egg diameter was 2.21~2.65 mm with several oil globule of 0.058~0.343 mm. Hatching occurred about 194 hours 23 minutes after fertilization at water temperature of $18{\sim}22^{\circ}C$. Newly-hatched larvae were 5.09~5.68 mm in total length(TL, mean: 5.38mm) with 10~11+18=28~29 myotomes and opened mouth and anus. Melanophores were distributed on the eye lens, on the head, around the yolk, on the dorsal part and the abdominal region of the trunk. After hatching 5 days larvae attained 6.12~6.68 mm in TL (mean: 6.47 mm), and the yolk sac was completely absorbed and transformed to postlarva stage. The larvae reached to the juvenile stage with all the fins were formed with complete set of fin rays (D. XII-12~13; A. III-8~10; P. 11~13; V. I-4~5) at the 22 days after hatching and of the larvae was 11.54 mm in total length. In 32 days after hatching, the juvenile was 13.05 mm in TL. This period was similar to adult in body form and the spot.

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Comparison of Acting Style Between 2D Hand-drawn Animation and 3D Computer Animation : Focused on Expression of Emotion by Using Close-up (2D 핸드 드로운 애니메이션과 3D 컴퓨터 애니메이션에서의 액팅(acting) 스타일 비교 -클로즈-업을 이용한 감정표현을 중심으로-)

  • Moon, Jaecheol;Kim, Yumi
    • Cartoon and Animation Studies
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    • s.36
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    • pp.147-165
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    • 2014
  • Around the turn of 21st century, there has been a major technological shift in the animation industry. With development of reality-based computer graphics, major American animation studios replaced hand-drawn method with the new 3D computer graphics. Traditional animation was known for its simplified shapes such as circles and triangle that makes characters' movements distinctive from non-animated feature films. Computer-generated animation has largely replaced it, but is under continuous criticism that automated movements and reality-like graphics devaluate the aesthetics of animation. Although hand-drawn animation is still produced, 3D computer graphics have taken commercial lead and there has been many changes to acting of animated characters, which calls for detailed investigation. Firstly, the changes in acting of 3D characters can be traced from looking at human-like rigging method that mimics humanistic moving mechanism. Also, if hair and clothing was part of hand-drawn characters' acting, it has now been hidden inside mathematical simulation of 3D graphics, leaving only the body to be used in acting. Secondly, looking at "Stretch and Squash" method, which represents the distinctive movements of animation, through the lens of media, a paradox arises. Hand-drawn animation are produced frame-by-frame, and a subtle change would make animated frames shiver. This slight shivering acts as an aesthetic distinction of animated feature films, but can also require exaggerated movements to hide the shivering. On the contrary, acting of 3D animation make use of calculated movements that may seem exaggerated compared to human acting, but seem much more moderate and static compared to hand-drawn acting. Moreover, 3D computer graphics add the third dimension that allows more intuitive movements - maybe animators no longer need fine drawing skills; what they now need is directing skills to animate characters in 3D space intuitively. On the assumption that technological advancement and change of artistic expressionism are inseparable, this paper compares acting of 3D animation studio Pixar and classical drawing studio Disney to investigate character acting style and movements.

Banded and Massive Iron Mineralization in Chungju Mine(I): Geology and Ore Petrography of Iron Ore Deposits (충주지역 호상 및 괴상 철광상의 성인에 관한 연구(I) : 지질 및 광석의 산출특성)

  • Kim, Gun-Soo;Park, Maeng-Eon;Enjoji, Mamoru
    • Economic and Environmental Geology
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    • v.27 no.6
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    • pp.523-535
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    • 1994
  • The strata-bound type iron ore bodies in the Chungju mine are interbedded with metamorphic rocks which are intruded by Mesozoic granitic rocks. The iron ore deposit occurs as layer or lens shape which are concordant with the metamorphic rocks. The iron ore is classified into banded and massive types based on the mode of texture and occurrence. Grain size and iron-oxides tend to become coarser toward massive ore than banded ore. Banded ores commonly contain internal layers defined by alternating magnetite- rich, hematite-rich, magnetite-hematite, and quartz-rich mesobands. The banded iron ore consists of hematite, magnetite, quartz, feldspar, and minor amounts of biotite, muscovite, chlorite, carbonates, epidote, allanite, and zircon. Massive ores which are characterized by high magnetite content occur in contact of granitic rocks. The massive iron ores consist mostly of magnetite and quartz, with minor amounts of hematite, pyrite, microcline, biotite, muscovite, chlorite, carbonates, epidote, allanite and zircon. Magnetite from banded and massive ores is almost pure $Fe_3O_4$ in composition, including 0.14 to 0.27 wt.% MnO and 0.10 to 0.15 wt.% MnO, respectively. Hematite of the ore contains 0.87 to 1.27 wt.% $TiO_2$ in banded ore and 3.44 to 6.96 wt.% $TiO_2$ in massive ore, respectively. Biotite shows a little compositional variation depending on ore types. Biotite of the banded ore has lower FeO, $TiO_2$ and $Al_2O_3$, and higher MgO and $SiO_2$ than the massive ore. The modes of occurrence and petrography of ore implies that massive ores might have been formed either under more reducing environments or higher temperature condition than banded ore. Banded ores might represent early episode of iron enrichment due to regional metamorphism. Massive ores might be related to the contact metamorphism resulting from late granitic intrusion.

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Comparison of Volumetric Modulated Arc Therapy and Non-coplanar Fixed-field Intensity Modulated Radiation Therapy for Irregular Target adjacent to Organ At Risk (손상위험장기에 인접한 불규칙한 모양의 타겟 치료 시, 용적변조회전 방사선치료와 비동일평면상의 빔을 이용한 세기변조 방사선치료의 유용성 평가 및 비교)

  • Kim, Kyung Ah;Na, Kyung Soo;Seo, Seok Jin;Lee, Je Hee
    • The Journal of Korean Society for Radiation Therapy
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    • v.29 no.1
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    • pp.57-68
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    • 2017
  • Purpose: The purpose of this study was to compare volumetric modulated arc therapy(VMAT) with fixed-field intensity modulated radiation therapy(IMRT) using non-coplanar beam when the shape of target is irregular and the location is adjacent to organ at risk(OAR). Materials and Methods: The subjects of this study were a total of 6 patients who had radiation therapy for whole scalp(2 patients), partial scalp(2 patients), and whole ventricle(2 patients) by True Beam STX(Varian Medical Systems, USA). VMAT plans consisted of coplanar or non-coplanar arcs which can minimize the volume of OAR included in beamlets. All fixed-field IMRT plans consisted of non-coplanar beams using more than 2 angles of Couch. Results: The VMAT and IMRT plans were compared with regard to the maximum dose of both lens, both optic nerves, optic chiasm, and brain stem and the mean dose of both eyeballs and hippocampus. VMAT plans showed higher dose than ncIMRT plans at more than 6 of all OARs in every patient, and the ratio was from 1.1 times to 8.2 times. In case of total scalp and partial scalp, the volume of brain which received more than 20 Gy in the VMAT plans was 2 times larger than the volume in the ncIMRT plans. In case of whole ventricle, there was no significant difference. Target coverage was satisfied in both plans($PTV_{100%}=95%$). The maximum dose in target volume and required monitor unit(MU) of ncIMRT were higher than them of VMAT plans. Conclusion: Even though ncIMRT is less efficient than VMAT with regard to required MU and treatment time, the dose to OARs is much lower than VMAT and PTV Coverage is similar with VMAT. If the shape of target is irregular and location is adjacent to OAR, comparison VMAT plan with ncIMRT plan deserves to be considered.

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The Analysis of Corneal Patterns in Korean 20s by Corneal Topography and Corneal Radii by Astigmatic Degree (각막지형도를 이용한 20대의 각막형상 및 난시도에 따른 각막곡률반경의 분석)

  • Kim, So Ra;Gil, Ji-Yeon;Park, Chang Won;Kim, Ji Hye;Park, Mijung
    • Journal of Korean Ophthalmic Optics Society
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    • v.16 no.3
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    • pp.273-281
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    • 2011
  • Purpose: In order to provide the fundamental information for the design development of RGP lenses and its clinical prescription, the corneal types of Korean twenties were analyzed according to corneal shapes, astigmatic degree, and the certain distance from the corneal apex. Methods: Corneal types of total 252 eyes in 20s were firstly classified, then their corneal radii from the certain distance from the corneal apex were measured by corneal topography and further analyzed based on the astigmatic degree. Results: Korean 20s' corneal types were classified as 14.3%(36 eyes) of round, 31.3%(79 eyes) of oval, 28.6%(72 eyes) of symmetric bow tie, 17.5%(44 eyes) of asymmetric bow tie, 8.3%(21 eyes) of irregular shapes. The round and oval typed corneas had mild astigmatic degree whereas the higher astigmatic degree in symmetric and asymmetric bow tie typed corneas were shown. The relative corneal radii of round and oval typed corneas at each distance from corneal apex were shown to consistently increase regardless of astigmatic degrees when they measured at certain distances from the corneal apex. However, the relative corneal radii of symmetric and asymmetric bow tie typed corneas within 1.0-1.5mm from the corneal apex were decreased, which showed steeper slope than it within 1.0 mm and somewhat different based on astigmatic degrees. Bigger change of corneal radii outer 3.5 mm from the corneal apex in symmetric bow tie typed corneas with astigmatism of 1.50-2.00 D and 2.25-2.75 D appeared. Conclusions: The consideration of radial change from the central cornea to peripheral cornea is necessary for manufacturing RGP lens and its prescription since they showed different change in corneal radii by corneal patterns and astigmatic degrees.

Development and Application of Scientific Model Co-construction Program about Image Formation by Convex Lens (볼록렌즈가 상을 만드는 원리에 대한 과학적 모형의 사회적 구성 프로그램 개발 및 적용)

  • Park, Jeongwoo
    • Korean Journal of Optics and Photonics
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    • v.28 no.5
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    • pp.203-212
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    • 2017
  • A scientific model refers to a conceptual system that can describe, explain, and predict a particular physical phenomenon. The co-construction of the scientific model is attracting attention as a new teaching and learning strategy in the field of science education and various studies. The evaluation and modification of models compared with the predicted models of data from the real world is the core of modeling strategy. However, there were only a limited data provided by the teacher in many studies of modeling comparing the students' predictions of their own models. Most of the students were not given the opportunity to evaluate the suitability of the model with the data in the real world. The purpose of this study was to develop a scientific model co-construction program that can evaluate the model by directly comparing the predicted models with the observed data from the real world. Through a collaborative discussion between teachers and researchers for 6 months, a 5-session scientific model co-construction program on the subject 'image formation by convex lenses' for second grade middle school students was developed. Eighty (80) students in 3 classes and a science teacher with 20 years of service from general public co-educational middle school in Gyeonggi-do participated in this 2-week program. After the class, students were asked about the helpfulness and difficulty of the class, and whether they would like to recommend this class to a friend. After the class, 95.8% of the students constructed the scientific model more than the model using the construction rule. Students had difficulties to identify principles or understand their friends, but the result showed that they could understand through model evaluation experiment. 92.5% of the students said that they would be more than willing to recommend this program to their friends. It is expected that the developed program will be applied to the school and contribute to the improvement of students' modeling ability and co-construction ability.

3D Histology Using the Synchrotron Radiation Propagation Phase Contrast Cryo-microCT (방사광 전파위상대조 동결미세단층촬영법을 활용한 3차원 조직학)

  • Kim, Ju-Heon;Han, Sung-Mi;Song, Hyun-Ouk;Seo, Youn-Kyung;Moon, Young-Suk;Kim, Hong-Tae
    • Anatomy & Biological Anthropology
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    • v.31 no.4
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    • pp.133-142
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    • 2018
  • 3D histology is a imaging system for the 3D structural information of cells or tissues. The synchrotron radiation propagation phase contrast micro-CT has been used in 3D imaging methods. However, the simple phase contrast micro-CT did not give sufficient micro-structural information when the specimen contains soft elements, as is the case with many biomedical tissue samples. The purpose of this study is to develop a new technique to enhance the phase contrast effect for soft tissue imaging. Experiments were performed at the imaging beam lines of Pohang Accelerator Laboratory (PAL). The biomedical tissue samples under frozen state was mounted on a computer-controlled precision stage and rotated in $0.18^{\circ}$ increments through $180^{\circ}$. An X-ray shadow of a specimen was converted into a visual image on the surface of a CdWO4 scintillator that was magnified using a microscopic objective lens(X5 or X20) before being captured with a digital CCD camera. 3-dimensional volume images of the specimen were obtained by applying a filtered back-projection algorithm to the projection images using a software package OCTOPUS. Surface reconstruction and volume segmentation and rendering were performed were performed using Amira software. In this study, We found that synchrotron phase contrast imaging of frozen tissue samples has higher contrast power for soft tissue than that of non-frozen samples. In conclusion, synchrotron radiation propagation phase contrast cryo-microCT imaging offers a promising tool for non-destructive high resolution 3D histology.

Effects of Self-Made Bismuth Shield Installation on Entrance surface Dose Reduction during Endovascular Treatment of Cerebral Aneurysms (뇌동맥류 코일 색전술시 자체 제작한 Bismuth 차폐체 설치의 피부선량 감소 효과)

  • Kim, Jae-Seok;Kim, Young-Kil;Choi, Jae-Ho
    • Journal of the Korean Society of Radiology
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    • v.13 no.2
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    • pp.175-183
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    • 2019
  • Cerebral nervous system intervention has been reported frequently due to radiation exposure such as blistering of the skin, hair loss, and erythema due to prolonged procedures. By applying ergonomically manufactured Bismuth (atomic number 83; Bi) shield to endovascular treatment of cerebral aneurysms, we aimed to minimize radiation exposure of scalp and lens from medical radiation exposure. The measurement site was the posterior part of the head, bilateral temporal part, bilateral quadriceps part, nose part, and the measuring part was attached to the optically stimulated Luminescence dosimeter (OSLD) Before and after the use, the entrance surface dose was compared and analyzed. The average entrance surface dose of group A (unshield) was 92.44 mGy, and group B was measured at 67.55 mGy. The average decrease in Group B was 26.92% compared to Group A. The entrance surface dose mean of the occipital region was measured at 146.08 mGy B group at 103.23 mGy and decreased by an average of 29.32% in group B compared to group A. The average entrance surface dose of the bilateral temporal part was measured in group A at 101.90 mGy group B at 72.69 mGy and decreased by an average of 28.67% in group B compared to group A. The average entrance surface dose for bilateral quadriceps part was measured at 27.51 mGy group B at 21.39 mGy and averaged 22.26% less in group B than group A. It is believed that the use of bismuth shields will be an alternative to reducing radiation disturbance due to temporary hair loss and other stochastic effects that may occur after the endovascular treatment of cerebral aneurysms procedure.