• 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 %).

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.3
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• pp.277-284
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• 2015

Purpose: The study aimed to evaluate the effect of circle contact lens wearing on visual quality of the eyes after a refractive surgery. Methods: The objective visual quality was evaluated for 40 eyes who did not get refractive surgery and 30 eyes who got a refractive surgery after applying plano circle contact lenses on their eyes, respectively. Modulation transfer function (MTF), objective scatter index (OSI) and the focusing ratio on retina (Strehl ratio) were measured by using optical quality analysis system (OQAS) and the correlation between pupil size and objective visual quality was analyzed by measuring the pupil size. Results: When wearing circle contact lens on the eyes after refractive surgery, MTF and Strehl ratio were reduced and OSI was increased compared with the eyes without refractive surgery. The eyes after a refractive surgery showed more significant difference changes in MTF, OSI and Strehl ratio according to the pupil size compared with those without refractive surgery. Conclusions: The results showed that wearing of circle contact lens after the refractive surgery has deteriorated the objective visual quality based on the quality of focused image on the retina. Therefore, we suggest that sufficient understanding and consideration about the deterioration of visual quality is necessary in the case of circle contact lens wearing after refractive surgery.

• Korean Journal of Crystallography
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• v.4 no.2
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• pp.54-62
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• 1993

The crystal shnture of dehydrated fully Cd2+-exchanged zeolite A evacuated at 2 × 10-6 Torr and 650℃ (a:12.189(2) A) and of its iodine sorption corrplex (a:12.168(2)A) have been netsmlmn by single uystal x-ray diffraction techliques in the cubic space group hkTn at 21(1)℃. The strutures were refined to final error indices, Ri:0.057 and R2 =0.063 with 186 reflections and Rl:0.082 and R2:0.085 with 181 reflections, respectively, for which 1>3σ(In both structure, six lie at two distinguished threefold axes of unit cell ten the crystal structure of an iodine sorption complex of Cd6-A four Cd2+ ions are recessed 0.69(1) A into the large cavity to complex each with from the (111) plane of 0(3), whereas two Cd2+ ions recessed 0.68(1) A into the sodalite unit Awximately 4.0 l3ions per nit cell are sorbed. Each bridge between a Cd2+ ion and 8-ring oxygens ((I-I-I)= 117(1) ˚ and 0(1)-I(1)-I(2)=172(1)). The near linear I-I-0 angle and its interatomic distance (I-0=3.57(3) A) are indicative of a weak charge transfer interacticn between the frarrework oxygen and iodine. The existence of In3 inside the large cavity indicates that the If ions and H ions may be produced by reaction of In vapor with water molecules which maybe associated with Cd2+ ions in partially dehydrated Cd6-A In3- ions may be produced by the combination of I- and I2.

• Journal of Korean Ophthalmic Optics Society
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• v.17 no.4
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• pp.419-424
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• 2012

Purpose: We were to obtain the basic data for studying kinetic visual acuity through the comparative analysis in kinetic visual acuity, visual acuity, refractive error, pupil size, and hand reaction time for college students. Methods: We had tested the kinetic visual acuity, visual acuity, refractive error and hand reaction time using the kinetic visual acuity tester (KOWA AS-4A), the hand reaction time program and auto-refractometer for thirty-nine male and same female optometry students with more than +0.1 LogMAR visual acuity in both eyes. And the results were examined gender differences of kinetic visual acuity and the factors correlation. Results: In the measured values of male, pupil size were 6.00 mm, hand reaction time 0.23 msec, refractive error -1.66 D, visual acuity -0.07, kinetic visual acuity 0.59 and pupil size 5.86 mm, hand reaction time 0.24 msec, refractive error -2.08 D, visual acuity -0.02, kinetic visual acuity 0.46 in female. It was significant difference for kinetic visual acuity values but other factors were not. The kinetic visual acuity and left visual acuity had the highest correlation, r=-0.406. The kinetic visual acuity indicated more excellent values in the case of increasing visual acuity and decreasing myopia amount. Conclusions: It was able to see that male college students were better than female for kinetic visual acuity and the visual acuity were related to kinetic visual acuity.

• Journal of the Korean Chemical Society
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• v.38 no.9
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• pp.621-627
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• 1994

Two crystal structures of dehydrated, $Ag^{+}$ and $Ca^{2+}$-exchanged zeolite A treated at $250^{\circ}C$ with 0.15 torr of Cs vapor have been determined by single-crystal X-ray diffraction technique in the cubic space group $Pm{\bar\3m$ at $21(1)^{\circ}C$ (a = 12.344(2) $\AA$ and 12.304(2) $\AA$). Their structures were refined to the final error indices, R (weighted), of 0.091 with 180 reflections, and 0.093 with 179 reflections, respectively, for which I > $3\sigma(I).$ In each structure, Cs species are found at four different crystallographic sites: 3 $Cs^{+}$ ions per unit cell are located at 8-ring centers, ca. 6.81∼7.14 $Cs^{+}$ ions are found on opposite 6-rings on threefold axes in the large cavity, ca. 1.93∼2.03 $Cs^{+}$ ions are found on threefold axes in the sodalite unit, and 0.53∼0.66 $Cs^{+}$ ions lie on opposite 4-rings. Also, ca. 4.12∼4.27 Ag atoms are located near the center of the large cavity. In these structures, excess cesium atoms in a unit cell are associated with other $Cs^{+}$ ions on a single threefold axis to form the linear cationic cluster $(Cs_4)^{3+}$. By blocking 8-rings, the $Cs^{+}$ ions may have prevented silver atoms from migrating out of the structure. The Ag atoms are likely to have formed hexasilver clusters at the centers of the large cavities. Each hexasilver cluster is stabilized by coordination to 14 $Cs^{+}$ ions.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.236-236
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• 2007

• Optical Science and Technology
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• v.5 no.3
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• pp.7-15
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• 2001

• The Science & Technology
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• v.35 no.1 s.392
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• pp.34-37
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• 2002

IT의 세계 - 3주전 약물복용 가려내는 "동공인식기술"/BT의 세계 - 새 차원의 생명과학 "유전체 정보"/NT의 세계 - 극한의 물질조작기술로 기능성 구조물 창출/ET의 세계 - 세계 인구 21억되면 지구는 낙원

• Journal of the Speleological Society of Korea
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• no.52
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• pp.25-34
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• 1997

동굴은 지하에 있는 동공으로서 미지의 세계이며 암흑의 세계이다. 예로부터 인간은 이 동굴의 대하여 공포심과 신비스러움을 동시에 느끼면서 생활하였다. 그 당시 동굴의 이용가치는 매우 작았으나 인간에게는 매우 중요한 장소로서 동굴의 위치와 규모, 주변환경에 따라서 동굴을 단순히 주거지, 피신처, 심신수련장 정도로 이용할 수밖에 없었다.(중략)

• Magazine of the Korea Institute for Structural Maintenance and Inspection
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• v.19 no.4
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• pp.45-47
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• 2015