• Title/Summary/Keyword: Aberration

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Atmospheric Correction and Velocity Aberration for Physical Sensor Modeling of High-Resolution Satellite Images (고해상도 위성영상의 센서모델링을 위한 대기 및 속도 보정)

  • Oh, Jae-Hong;Lee, Chang-No
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.29 no.5
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    • pp.519-525
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    • 2011
  • High-resolution earth-observing satellites acquire substantial amount of geospatial images. In addition to high image quality, high-resolution satellite images (HRSI) provide unprecedented direct georegistration accuracy, which have been enabled by accurate orbit determination technology. Direct georegistration is carried out by relating the determined position and attitude of camera to the ground target, i.e., projecting an image point to the earth ellipsoid using the collinearity equation. However, the apparent position of ground target is displaced due to the atmosphere and satellite velocity causing significant georegistration bias. In other words, optic ray from the earth surface to satellite cameras at 400~900km altitude refracts due to the thick atmosphere which is called atmospheric refraction. Velocity aberration is caused by high traveling speed of earth-observing satellites, approximately 7.7 km/s, relative to the earth surface. These effects should be compensated for accurate direct georegistration of HRSI. Therefore, this study presents the equation and the compensation procedure of atmospheric refraction and velocity aberration. Then, the effects are simulated at different image acquisition geometry to present how much bias is introduced. Finally, these effects are evaluated for Quickbird and WorldView-1 based on the physical sensor model.

Optimum design of the finite schematic eye using spherical aberration (구면수차를 이용한 정밀모형안의 최적화)

  • 김상기;박성찬
    • Korean Journal of Optics and Photonics
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    • v.13 no.3
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    • pp.266-271
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    • 2002
  • The finite schematic eye based on spherical aberration and Stiles-Crawford effect is designed by an optimization method. It consists of four aspherical surfaces. The radius of curvature, thickness, asphericity, and spherical aberration are used as constraints in the optimization process. Stiles-Crawford effect in the pupil is considered as a weighting value for optimum design. The designed schematic eye has effective focal length of 20.8169 mm, back focal length of 15.4820 mm, front focal length of -13.8528 mm, and image distance of 15.7150 mm. When the pupil diameter is 4 mm, the diameter of entrance pupil and exit pupil are 4.6919 mm and 4.2395 mm, respectively. From the data of 75 measured Korean emmetropic eyes, this finite schematic eye is designed first in Korea.

Genotoxicity Studies of the Complex of Acriflavine and Guanosine (Acriflavine과 Guanosine 복합체(AG60)의 유전독성시험)

  • 정영신;홍은경;김상건;안의태;이경영;강종구
    • Environmental Mutagens and Carcinogens
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    • v.22 no.2
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    • pp.106-111
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    • 2002
  • AG6O, the complex of acriflavine and guanosine, has been shown to possess the synergistic antitumorigenic activity in the previous paper (J. Pharm. Pharmacol. 1997, 49:216). In this study, we have investigated the genotoxic properties of AG60 using in vitro and in vivo system such as Ames bacterial reversion test, chromosomal aberration assay and micronucleus assay. In Ames reverse mutation test, AG60 treatment at the dose range up to 250 $\mu\textrm{g}$/plate caused the dose-independent random induction of the mutagenic colony formation in S. typhimurium TA98, TA100, TA1537, and E. coli WP2uvrA, while any mutagenic effect of AG60 wasn't observed in S. typhimurium TA1535. Any significant chromosomal aberration wasn't observed in chinese hamster lung (CHL) fibroblast cells incubated with PBS or AG60 at the concentrations of 2.5, 5, 10 $\mu\textrm{g}$/$m\ell$ for 24 hours without but even with 59 metabolic activation system for 6 hours. In vivo ICR mice, the intramuscular injection of AG60 at the doses of 7.15, 14.3, and 28.6 mg/kg did not induce the frequency of micronucleus formation. However, mitomycin C, as one of the positive controls at the dose of 2 mg/kg caused the 8.4% induction in the frequency of micronucleus and 24% increase in the chromosomal aberration.

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Optical constant of the reduced eye based on theoretical finite model eye (이론적 정밀모형안에 기초한 환산모형안의 광학상수)

  • 김상기
    • Korean Journal of Optics and Photonics
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    • v.15 no.3
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    • pp.268-273
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    • 2004
  • A finite model eye based on longitudinal spherical aberration is designed by an optimization method. Longitudinal spherical aberration for pupil diameter between 1 mm and 8 mm is graphed theoretically and compared with other model eyes. The chromatic dispersions are adjusted to fit experimentally observed chromatic aberration of the eye. This is a finite model eye with four a spheric refracting surfaces. It has an effective focal length of 15.842 mm. A designed reduced eye has an equivalent power of 63.12 Diopter, curvature radius of 5.281 mm, index of 1.33333, and axial length of 21.123 mm.

Genotoxicity Test of Bojungikkeehapdaechilki-tang water extract (보중익기합대칠기탕(補中益氣合大七氣湯) 추출물의 유전독성 평가)

  • Hwang, Hui-Jeung;Byun, Joon-Seok;Heo, Jin-Il
    • Herbal Formula Science
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    • v.14 no.1
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    • pp.141-167
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    • 2006
  • The genotoxicity of water extract of Bojungikkeehapdaechilki-tang was tested by In Vitro Chromosome Aberration Test. Bacterial Reverse Mutation Assay and Micronucleus test according to OECD Guidelines and KFDA Guidelines. The obtained results were as follows : 1. Chromosome Aberration Test: In Vitro Chromosome Aberration Test of Bojungikkeehapdaechilki-tang extracts was carried out using cultured Chinese hamster lung cells in the presence and absence of metabolic activation system(S-9 mix). No significant changes in the number of aberrant metaphases having structural and number of aberrations were detected in Bojungikkeehapdaechilki-tang extracts treated groups. 2. Bacterial Reveres Mutation Assay: Bojungikkeehapdaechilki-tang extracts was evaluated for its potential to induce reverse mutation in the histidine auxotroph strains of Salmonella typhimurium such as TA100, TA1535, TA98 and TAl537 and the tryptophan auxotroph strain of Escherichia coli WP2 uvrA. No significant changes in the number of revertant colonies compared to its negative control were detected in Bojungikkeehapdaechilki-tang extracts treated groups against all 5 strains. 3. Micronucleus test: Micronucleus test of Bojungikkeehapdaechilki-tang extracts were performed using specific pathogen free 7-week old male ICR mouse. No significant changes in the number of micronucleated polychromatic erythrocytes among 2000 polychromatic erythrocytes compared to negative control were detected in all Bojungikkeehapdaechilki-tang extracts treated groups. In summarized above-mentioned results, it is concluded that Bojungikkeehapdaechilki-tang extracts have not genotoxicity against In Vitro Chromosome Aberration Test, Bacterial Reverse Mutation Assay and Micronucleus test.

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Off-axis Two-mirror System with Wide Field of View Based on Diffractive Mirror

  • Meng, Qingyu;Dong, Jihong;Wang, Dong;Liang, Wenjing
    • Journal of the Optical Society of Korea
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    • v.19 no.6
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    • pp.604-613
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    • 2015
  • An unobstructed off-axis two-mirror system is presented in this paper. First a suitable initial configuration is established based on third-order aberration theory. In order to achieve a wide field of view (FOV) with high image quality , the diffractive mirror is adopted in the two-mirror system to increase the optimization freedom and the aberration relationship between diffractive phase coefficients and Zernike coefficients is derived. Furthermore, a complete comparison design example with a focal length of 1200 mm, F-number of 12, and FOV of 40° × 2° is given to verify the aberration correction ability of the diffractive mirror. The system average wavefront error is 0.007 λ (λ=0.6328 μm) developed from 0.061 λ when the system didn’t adopt the diffractive mirror. In this system the phase modulation function of the diffractive mirror is established as an even function of x, so we could obtain a symmetrical imaging quality about the tangential plane, and the symmetric aberration performance also brings considerable convenience to alignment and testing for the system.

Effect of DNA Repair Inhibitors and Iron on the Chromosome Aberration Induced by Bleomycin and Hydrogen Peroxide in CHO Cells (DNA 회복합성저해제 및 철이 Bleomycin과 과산화수소에 의해 유발된 CHO 세포의 염색체 이상빈도에 미치는 영향)

  • 정해원;유은경
    • Journal of Environmental Health Sciences
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    • v.19 no.4
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    • pp.59-66
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    • 1993
  • The cellular toxicity and antitumor effects of bleomycin are thought to be occurred by formation of O$_2$-Fe$^{2+}$-bleomycin complexes that degrade DNA and release O$_2^-$ and $^{\cdot}$OH radicals. Hydroxyl radicals derived from hydrogen peroxide seem most likely to be involved in the various stages of carcinogenesis, and transition metals such as iron play a central role in activation of bleomycin and in formation of hydroxyl radicals. This study was performed to investigate whether treatment with ferrous sulfate increase chromosome aberration induced by bleomycin and hydrogen peroxide, and whether there is different repair mechanism for DNA damage induced by those chemicals. Treatment with 3AB, Ara C, during G$_1$ and post-treatment with caffeine, and Hu during G$_2$ increased the frequency of chromosome aberration induced by bleomycin but post-treatment with caffeine only did function that way when hydrogen peroxide was treated. When 6.6X 10$^{-7}$ M of bleomycin or 5.0X10$^{-5}$M of hydrogen peroxide were treated simultaneously with iron, the frequency of chromosome aberration was reduced, if compared with the results by bleomycin or hydrogen per oxide alone.

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Measurement of Spherical Aberration Coefficient of the Objective Lens in KBSI-HVEM (KBSI-HVEM 대물렌즈의 구면수차 계수 측정)

  • Kim, Young-Min;Shim, Hyo-Sik;Kim, Youn-Joong
    • Applied Microscopy
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    • v.37 no.2
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    • pp.111-121
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    • 2007
  • Coefficient of spherical aberration of the objective lens in the KBSI-HVEM was evaluated by diffractogram method. Instrumental resolution was also discussed with this method. In order to improve the accuracy, digital processing and graphical curve fitting for intensity profile of diffractogram were employed. Experimental concerns where the optimal procedure of the measurement con be accomplished for this study were discussed. The spherical aberration coefficient $(C_s)$ was estimated to be $2.628{\pm}0.04\;mm$ from this study, which was almost coincident with the value of the manufacture's suggestion $(C_s=2.65\;mm)$.

Aberration effects on white light interferometry (광학계 수차에 의한 백색광 간섭계의 측정 오차에 대한 연구)

  • 박민철;김승우
    • Korean Journal of Optics and Photonics
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    • v.12 no.5
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    • pp.362-370
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    • 2001
  • We prove that 3-D profile mapping using white light interferometry has systematic errors caused by aberrations of the optimal system. The tilt of an object invokes an offset between the object and the reference ray, which eventually makes the aberration cancel incompletely. The fringe peak of a white light interferogram is mainly affected by the aberration effect while the envelope peak remains stable. By the difference between the two peaks, it is easily confirmed how much the error existed in the fringe peak. Experimental results prove that the error caused by aberration is varied by object tilt, microscope NA, optics alignment within the range of $\pm$50nm.

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Toxicity Assessment of a No-Pain Pharmacopuncture Extract Using a Standard Battery of In Vitro Chromosome Aberration Tests

  • Ji Hye Hwang
    • Journal of Pharmacopuncture
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    • v.27 no.1
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    • pp.38-46
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    • 2024
  • Objectives: Genotoxicity is evaluated through a chromosomal aberration test using cultured mammalian cells to determine the toxicity of no-pain pharmacopuncture (NPP), which has recently been used to treat musculoskeletal pain disorders in Korean medical clinical practice. Methods: An initial test was performed to determine the dosage range of the NPP, followed by the main test. In this study, NPP doses of 10.0, 5.0, and 2.5%, and negative and positive controls were tested. An in vitro chromosome aberration test was performed using Chinese hamster lung cells under short-term treatment with or without metabolic activation and under continuous treatment without metabolic activation. Results: Compared with the saline negative control group, NPP did not significantly increase the frequency of chromosomal abnormalities in Chinese hamster lung cells, regardless of the presence or absence of metabolic activation. Additionally, the number of cells with structural chromosomal abnormalities was significantly higher in the positive control group than that in the negative control group that received saline. Conclusion: Based on the above results, the chromosomal abnormality-producing effect of NPP was determined to be negative under these test conditions.