• Journal of Korean Ophthalmic Optics Society
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• v.1 no.1
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• pp.65-72
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• 1996

The general property of plastic ophthalmic lens has been reviewed by the optical property and polymer structure. A PMMA which is synthesized by the polymerization of monomers of two or more kinds is termed a copolymer, and the main chain composes a skeleton of molecular structure in the polymer. Refraction index of polymer was governed mainly by the polarization of molecular and was followed to increase it conspicuously as Cl, Br, and Iodine was substitude to hydrogen. Thermal dependence of refraction index of polymer show that the higher distinctive characteristic than glass material.

• KOREAN POULTRY JOURNAL
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• v.33 no.10 s.384
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• pp.116-118
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• 2001

선천 면역(Maternal immunity)은 모체에서 유래된 lgG class의 항체(모체이행항체)에 의한 면역이다. 이와 같은 면역은 주로 체액성 면역(혈중항체)과 관계 있으며, 국소면역 또는 세포면역은 관여하지 않는다. 일반적으로 1일령 병아리의 항체가는 모계군의 혈청역가 보다 약간 낮게 나타난다. 부화 후 처음 4일간은 난황으로부터 흡수를 함으로써 혈중 항체가가 떨어지지 않고 비슷하게 유지되다가 그 이후 항체가는 차츰 감소하게 된다. 항체가가 감소하는 수준은 닭의 종류에 따라 다른데, 이것은 생리대사와 성장에 좌우되기 때문이다 일반적으로 항체가가 반으로 감소하기까지의 기간(반감기)은 육계의 경우 3일에서 3.5일, 종계의 경우 4.5일, 산란계의 경우 5.5일로 나타난다. 1일령 때의 항체 역가 수준, 닭의 종류, 항체가를 측정하는 혈청검사의 방법 등에 따라 모체이행 감소 수준이 다르긴 하지만 보통 수주 이내에 완전히 소실되게 된다.

• Korean Journal of Environmental Biology
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• v.20 no.3
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• pp.245-255
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• 2002

In order to obtain the basic information for seedling production of venus clam, Protothaca jedoensis, the annual reproductive cycle was investigated mainly by histological observation from September 1998 to August 1999. P. jedoensis was dioecious. The gonads are located between the digestive diverticula and muscle tissue of the foot. The ovary was composed of a number of ovarian sacs, and the testis was composed of several testicular tubules. The condition index was reached its maximum (20.0) in February, and then decreased to 11.5 in June. In August, the value was the lowest (9.0) and then increased slowly. Minimum size for the sexual maturation of individuals were 38.4 mm in shell length. One the other hand, the size of mature oocytes was ranged to $50-60\mu{m}$ in diameter and testis-ova was observed in testis of the mature stage. The reproductive cycle of P. jedoensis could be classified into five successive stages: early active (December to February), late active (January to April), ripe (March to July), partially spawned (June to August) and spent/inactive (July to January) stages.

• Korean Journal of Optics and Photonics
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• v.30 no.3
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• pp.114-119
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• 2019

This paper discusses the development of a Raman lidar system for remote detection and measurement of hydrogen gas by using a photon counter. The Raman signal of the hydrogen gas is very weak and has a very low signal-to-noise ratio. The photon counter has the advantage of improving the signal-to-noise ratio, because it has a discriminator to eliminate the background noise from the Raman signal of the hydrogen gas. Therefore, a small and portable Raman lidar system was developed using a low-power pulsed laser and a photon-counter system to measure the hydrogen gas concentration remotely. To verify the capability of measuring hydrogen gas using the developed photon-counting Raman lidar system, experiments were carried out using a gas chamber in which it is possible to adjust the hydrogen gas concentration. As a result, our photon-counting Raman lidar system is seen to measure a minimum concentration of 0.65 vol.% hydrogen gas at a distance of 10 m.

• Korean Journal of Optics and Photonics
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• v.32 no.4
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• pp.147-152
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• 2021

We report high-power continuous-wave operation of a Yb-doped fiber laser at 1070 nm, pumped by high-power laser diodes at 976 nm. Based on theoretical calculation of the stimulated Raman scattering and temperature distribution in the fiber, we construct a bidirectionally pumped Yb-fiberlaser system incorporating a pair of fiber Bragg gratings and a cladding light stripper. The fiber laser yields 3.0 kW of continuous-wave output at 1070 nm in a diffraction-limited beam with M² ≈ 1.26 for 4.1 kW of incident pump power, corresponding to a slope efficiency of 81.5%. The prospects for further power scaling are discussed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.1
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• pp.11-19
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• 2002

We studied the characteristics of catch fluctuation and distribution of yellow tail resources in Korean Waters from 1991 to 2000. The obtained results are summarized as follow, The distribution of yellow tail resources in Korean Waters was showed by mooving north-ward groups from Spring to Autumn and south-ward groups from Autumn to Winter with they passed Winter and spawned from the south of Jeju Island and Tsushima current. Therefore, the fishing ground of yellow tail by handline fishing around Marado targets a school of yellow tails which migrate south-ward so as to winter and spawn.

• The Journal of the Korea Contents Association
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• v.15 no.6
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• pp.297-302
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• 2015

High-energy medical linear accelerator on the dose to the thyroid cancer during radiotherapy were evaluated using optical stimulation luminescence dosimeters(OSLD) using. Scattered's influence in the case of 3D-CRT 25.4 mSv, 28.8 mSv, 31.3 mSv, 26.5 mSv, 27.4 mSv 5 times with an average 27.9 mSv, in the IMRT 46.8 mSv, 43.2 mSv, 42.3 mSv, 41.5 mSv, 44.1 mSv to five times the average of 43.6 was the result of mSv. In the case of light neutron dosimetry results 3D-CRT 3 mSv, 3 mSv, 3.4 mSv, 3.5 mSv, 3.1 mSv to five times the average 3.2 mSv, in the IMRT 5.1 mSv, 4.8 mSv, 4.2 mSv, 4.8 mSv, 4.9 mSv, to five times the average of 4.7 was the result of mSv. Both parties and the light scattered neutrons were significantly appreciated compared to IMRT 3D-CRT. Treatment of cancer using radiation workers, as in this study, and that a significant amount of scattered rays in the adjacent normal tissues during radiation therapy using energy assessment to influence by fully aware of this information is necessary for the exposure reduction efforts the feed.

• Korean journal of applied entomology
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• v.33 no.2
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• pp.56-59
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• 1994

Life histoy of Nysius plebejrrs, the most injurious pest in chysanthemun cultivation in Korea, was studies both in field and inseday in Chinju during 1991 and 1992 seasons, and resulis are summarized as below 7hls insect has 3 generation per year, adult peaks on the mid April, mid June and late August, and the highest number of adults were attracted to the light tmp from the late August through mid September. Overwntered generation and needed 6-7weeks from egg rnatulity m spring, and 5-6 weeks, for both the first and second generation m summer, Incubation egg periods were 142, 9.3 and 7.2 days, nymphal penods were 45.2, 32.1 and 31.2 days, and total growth periods, were 59.4. 41 4 and 38.4 days, respect~vely for the overwintered, flst and second generation. Ovipositional penods were 25.6, 23.4 and 21.2 days. and number of eggs Iald by each female were 41.5. 37.2 and 35.4 days, respedively of each generation Longevities of female were 326, 27.5 and 25.1 days. and of male were 15 2, 12.3 and 12.1 days. respectively of each generation. Sex ratlo was about 1:1 in all generation, and eggs were laid in mass on the surface of leaves or stems of the host plants. This insed over-wmters as adult (90%) or 5th instar nymph (10%), however, over-wintering adults seem to be sexually premature, and mating take place actively in the following spring.

• Korean Journal of Ichthyology
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• v.20 no.3
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• pp.190-197
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• 2008

Spatio-temporal distribution of eggs and larvae of Japanese anchovy Engraulis japonica in the southern sea of Korea was determined using data obtained from icthyoplanktonic surveys and oceanographic observations between Goheung Peninsula and Goeje Island from May to August 2007. Commercial anchovy catch and size composition from four local fishery cooperative associations were also analyzed in relation to the geographic distribution of eggs and larvae. The abundance of anchovy eggs increased from May to July and was lowest in August. Eggs were mainly distributed between Namhae Island and Goeje Island, where water temperatures were $15{\sim}24^{\circ}C$ and salinities were 32~35‰. In 2007 anchovy landings between Namhae Island and Goeje Island were 11,409 tons at Tongyeong association, 4,137 tons at Masan association, and 2,487 tons at Sacheon association. However, landings between Goheung and Yeosu Peninsula were only 4,411 tons (at Yeosu association). The catch by anchovy tow net was high in the area where eggs were abundantly distributed. This indicates that the distribution of egg density was directly correlated with recruitment of E. japonica. All growth stages were abundant in the study area, indicating that this area is a major spawning and growing ground of E. japonica in Korean waters.

• Korean Journal of Ichthyology
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• v.9 no.1
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• pp.61-70
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• 1997

The spawning season, growth and feeding habit of tubesnout, Aulichthys japonicus were examined from the samples collected by a small beam trawl in the Zostera marina belt at the coastal water off Hamduck, Cheju Island, from May 1993 to May 1994. Tubesnout was the dominant species of overall 58 species collected in the study area throughout the year. The larvae and juvenile of tubesnout in the frequency distributions of body length began to appear in the Z. marina belt in March, and adults disappeared after May in the following year. The gonad weight index (GWI) and the condition factor (K) were high from November 1993 to January 1994 for males, while females were high from February to May 1994. Although tubesnout is an oviparous fish, males have the urogenital papilla. These results suggest that they were fertilized between November and January, and then males seemed to be died or move into other places. Females were examined to spawn from February to May. The stomach contents of tubesnout were dominated by copepoda smaller than ca. 1mm, Paracalanus, Oithona, Acartia, Oncaea and Harpacticoidae, accounting for 97% of total food items. The feeding habit of tubesnout did not vary by size. The fishes fed on Calanus, Euchaeta and decapoda larvae larger than ca. 3mm in March and April during the spawning season.