• Title/Summary/Keyword: compound eyes

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Refractive Error in Middle and High School Pupils (중고등학생의 안굴절 상태조사 및 연구)

  • Pyo, Kyoung-Min;Kim, Woong-Tea
    • Journal of Korean Ophthalmic Optics Society
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    • v.1 no.1
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    • pp.119-125
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    • 1996
  • From 1995. 3. 20 to 1995. 4. 10 refractive errors were surveyed on the 1,197 middle and high school pupils in Dong-Du-Cuon area. On the basis of the power of the old glasses or newly examined power, we surveyed the distribution of the refractive errors according to their types, ages, heights, weights and differences between both eyes. Among 2,394 eyes examined, 1,125eyes(47%) were emmetropia, 967 eyes(40.4%) were myopic, and 302eyes(12.6%) were hyperopic. As to the distribution of refractive errors, simple myopia(42.9%) was most common, and mixed astigmatism and compound hyperopic astigmatism were below 1%, Among the types of astigmatism, 62% were with the rule, 23% were against the rule and 15% were oblique, Differences between both eyes, the left eye showed more myopic than those of right eye. The distribution of myopia according to their ages, 27.7 at age 11, 38.5% at age 12, 35.5% at age 41.5% at age 14, 37.7% at age 15, 48.3% at age 16 and 46.8% at age 17., there was a significant increase in the prevalence of the myopia but that or hyperopia decreases with increases of age.

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The Clinical Study on Spectacle Wearers of Highschool Students (고등학생 안경착용자의 착용상태에 관안 임상적 연구)

  • Kim, Sang-Kyun;Sung, A-Young
    • Journal of Korean Ophthalmic Optics Society
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    • v.9 no.1
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    • pp.19-27
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    • 2004
  • The purpose of this study is to survey spectacle wearers's way of thinking through the questionaire and to investigate their wearing conditions through fitting conditions, the pantascopic angle, vertex distance, the coincidence of vertical and horizontal distance between optical center of the lens and pupillary distance of the eye in random selected 150 ametropic corrective wearers in the age of 17 to 19. The results are as follows : 1. The most popular causes of physical complaints in the ex-wearing spectacle are frame pressure(34.0%), slipping forward(30.0%) and most popular visual complaints are blur vision(30.0%) and asthenopia(20.0%). 2. The most common physical or visual complaints in the present wearing spectacle are slipping forward(30.0%), pressure (50.0%), color(10.0%). 3. Myopic glasses wearers accounted for 56.7% of the subjects, the others were compound myopic astigmatism. In 60% of the subjects' binocular diopter did not coincide. 4. In the pantascopic angle of the both eyes coincide in 66.7% of the subjects. The average of pantascopic angle is $10.07^{\circ}$. 5. In the vertex distance of the both eyes coincided in 65.3% of the subjects. the he average of vertex distance is 13.6 mm. 6. Among 150 eyes with monocular, the vertical distance between optical center of the lens and pupillary distance of the eye is within the RAL-RG 915 that is tolerance of ophthalmic dispensing in German Standards in 82 eyes (54.6%). 7. Among 150 eyes with monocular, the horizontal distance between optical center of the lens and pupillary distance of the eye is within the RAL-RG915 that is tolerance of ophthalmic dispensing in German Standards in 86 eyes(57.3 %).

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Relationship on the Refractive Status of the High School 3rd Grade Students with Subnormal Visual Acuity in Gwangju Metropolitan City (광주지역 고등학교 3학년생의 비정시안의 굴절상태에 대한 고찰)

  • Yoon, Young;Ryu, Geun-Chang
    • Journal of Korean Ophthalmic Optics Society
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    • v.12 no.3
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    • pp.105-110
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    • 2007
  • To investigate the ametropia and refractive error of 222 ametropic eyes of the 111 high school students in Gwangju Metropolitan City, the visual acuity test was performed by the object and subject method. 85% of the eye types were positive for myopia, 14% for emmetropia, and 1% for hyperopia, respectively. 38% of the abnormal refraction eyes were positive for simple myopia, 4% for myopia simple astigmatism, 56% for myopia compound astigmatism, and 0% for simple hyperopia, 0% for hyperopia simple astigmatism, 2% for hyperopia compound astigmatism, 0% for mixed astigmatism, respectively. 92% of the axes fo astigmatism were for astigmatism with-the-rule, 6% for astigmatism against-the rule, 2% for astigmatism oblique, respectively. As for the astigmatic power, 0.50 < cylinder < 1.00D was 68%, 1.00 < cylinder < 2.00D was 25%, and anything over the 2.00 cylinder D was 7%. As for the equivalent spheric power of myopic abnormal refraction eyes, -0.50 < spheric equivalent < -2.00D was 26%, -2.00D < spheric equivalent < -6.00D was 55% and anything over the -6.00D was 19%. The rate of wearing glasses was 74%. It increases compared to 20 years ago. 91% of the eye test place was the optical shop, 9% the eye doctor hospital. 80% of the students need to change their optical lenses because spherical equivalent power was over 0.50D.

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Electron Microscopical Observation on the Compound Eye in Meimuna mongolica D. (쓰름매미 (Meimuna mongolica D.) 복안의 전자현미경적 관찰)

  • Choi, Choon-Keun;You, Kwan-Hee;Shin, Kil-Sang;Choe, Rim-Soon
    • Applied Microscopy
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    • v.9 no.1
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    • pp.1-11
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    • 1979
  • Electron microscopic studies were carried out to investigate the fine structure of ommatidia of the compound eyes in Meimuna mongolica D. The crystalline cone appears round, and is composed of four double-membraned cone cells and surrounded by pigment cells having many pigment granules. The rhabdom is a closed type, and is composed of four rhabdomeres Its cross section reveals lamellated microvilli which are oriented in four different directions suggesting that these represent four photoreceptive sites. The microvilli, in a cross sectional view, are hexagonal in shape with a central axis inside. There are usually eight retinular cells arranged radially from the rhabdom, but in some retinular layers seven or nine retinular cells could be observed. The cytoplasm of each retinular cell is interconnected with that of microvilli of the rhabdomere, but the appearance of this interconnection varies depending on the number of retinular cells.'The retinlilar cells neighboring the microvilli seem to have well-developed perirhabdomal vacuoles and mitochondria as well as pigment granules surrounding these vacuoles.

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The Effects of LED Light Quality on Foliage Plants Growths in Interior Environment (실내에서 LED광질이 관엽식물의 생장에 미치는 영향)

  • Kim, Myung-Seon;Chae, Soo-Cheon;Lee, Myung-Won;Park, Gab-Soon;Ann, Seoung-Won
    • Journal of Environmental Science International
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    • v.22 no.11
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    • pp.1499-1508
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    • 2013
  • In the results of investigating the role of LED light quality in enhancing the ornamental value of indoor foliage plants, amber and red light increased plant height, leaf width, and leaf stalk, and the consequent tree shape decreased the ornamental value. The chlorophyll content increased significantly under white light and compound light. With regard to the effect of plant leaf color on ornamental value, the value of lightness was markedly enhanced by red light. As to the functionality of plants according to photosynthetic activity, plants such as Dieffenbachia, Clusia, and Dracaena were found favorable to those staying indoors for a longtime from morning to evening. Spathiphyllum, and Ficus were found to be recommendable for indoor spaces used actively during afternoon because their photosynthesis was activated in the afternoon. With regard to power consumption according to light quality, white light consumed 119 W/hour, around 45% lower than that of fluorescent lamps, so it is considered the optimal artificial light quality that can enhance energy efficiency. Red light consumed 72 W/hour, only 33% of that of fluorescent lamps, but it was not considered the optimal light quality because plant growth was poor under the light quality. White light and compound light were found to be the ideal light sources for improving the functionality and ornamental value of indoor plants and reducing the cost of maintenance, but because compound light hinders people from recognizing the original color of plants and makes their eyes easily tired, white light was considered the optimal light satisfying all of the ornamental value, economic efficiency and functionality resulting from plant growth.

Effect of the Sag Height of a PDMS Microlens on the Acceptance Angle of an Artificial Compound Eye (겹눈 모사 구조체에서 마이크로 렌즈의 높이가 빛의 수용각에 미치는 영향 연구)

  • Jihyun, Jung;Mihee, Park;Hyerin, Song;Kyujung, Kim
    • Korean Journal of Optics and Photonics
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    • v.34 no.1
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    • pp.13-21
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    • 2023
  • We have investigated the acceptance angle and imaging performance of a curved artificial compound eye (ACE), depending on the sag height of the microlens array to maximize its sensitivity to light. When the h/r values increased from 0.22 to 0.37, the acceptance angle of the curved ACE was expanded from 28.70° to 49.02°, which is an enhancement by 70.8%. With the designed optical system, it was demonstrated that a microlens located at the 23rd position from the center of the main lens could still focus an incident beam tilted at 56.35°, so that the letter F was clearly observed.

Redescriptions of Two Closely Resembling Chrysotoxum Species (Insecta: Diptera: Syrphidae) New to Korea

  • Suk, Sang-Wook;Choi, Deuk-Soo;Han, Ho-Yeon
    • Animal Systematics, Evolution and Diversity
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    • v.24 no.3
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    • pp.299-305
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    • 2008
  • As a result of ongoing systematic study of the genus Chrysotoxum, we have discovered C. ramphostomus and C. tuberculatum for the first time in Korea. These two species closely resemble each other and need to be identified with caution. We here provide detailed redescriptions and illustrations with their diagnostic characters indicated. Chrysotoxum tuberculatum can be readily distinguished from C. ramphostomus by the following characteristics: 1) hind trochanter with small tubercle; 2) compound eyes apparently bare; 3) basal 1/5 of hind femora brownish yellow; and 4) male genitalia asymmetrical in caudal view.

A Rare Tropical Stonefly Brahmana flavomarginata (Plecoptera: Perlidae: Acroneuriinae) from Vietnam

  • Cao, Thi Kim Thu;Bae, Yeon Jae
    • Animal Systematics, Evolution and Diversity
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    • v.29 no.2
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    • pp.179-183
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    • 2013
  • The perlid stonefly Brahmana flavomarginata Wu, originally described from China from the male adult, is described using reared male and female adults and nymphs from Vietnam. The male adult of B. flavomarginata is distinguished from its congeners by the blackish-brown body color and distinct head marking, hemitergal triangular chitin plates, and a median semicircular smooth subgenital plate (hammer) on the abdominal sternum IX. The female adult has a large and round subgenital plate which extends to the posterior margin of the abdominal sternum X. The nymph can be distinguished by the relatively small compound eyes and the body covered by many long stout setae and short golden brown hair-like setae. This species is known in southwestern China (Yunnan Province) and northern Vietnam (Lao Cai Province, Cao Bang Province).

Protective effect of Kohl-Chikni Dawa against galactose-induced cataract in rats

  • T.A., Siddiqui;Z., Shadab;N., Ayasha;S.H., Alavi
    • Advances in Traditional Medicine
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    • v.4 no.2
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    • pp.82-86
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    • 2004
  • The efficacy of Kohl-Chikni Dawa (KCD), a compound ophthalmic formulation of Unani medicine, to control cataract development was explored in rats fed 25% galactose with the diet for 6 months. When one drop of 3% KCD solution was applied (once and twice daily) in both eyes for 6 months in galactose-fed rats, a significant reduction of lens opacification was noticed. The morphological changes of the lenses were observed every month by slit-lamp biomicroscope. These results suggest that the local application of 3% KCD solution possesses anticataract effect in galactose-fed rats.

Re-description of Sea Spider Cilunculus armatus (Pycnogonida: Ammotheidae) from Korea

  • Lee, Damin;Park, Jin-ho;Kim, Won
    • Animal Systematics, Evolution and Diversity
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    • v.36 no.4
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    • pp.330-335
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    • 2020
  • The sea spider genus Cilunculus Loman, 1908 comprises 33 species having short chelifores, separate lateral processes, and a hood structure on the cephalic segment. A pycnogonid species, Cilunculus armatus(Böhm, 1879), was collected from Baekdo Island and Chujado Island, Korea. This species is characterized by having a hood structure on the cephalic segment, separate lateral processes, a low ocular tubercle without eyes, and 3-segmented chelifores. In the examined material, chela shape, arrangement of compound spines on strigilis, and number of heel spines at propodus were different from the previous literatures. Here, we examined C. armatus collected in Korean waters and provided illustrations and pictures in detail.