• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.94.1-94.1
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• 2012

천리안위성은 우리나라 최초의 정지궤도복합위성(COMS: Communication, Ocean, and Meteorological Satellite)으로 2010년 6월 27일, 남미 기아나 쿠루기지에서 아리안-5 로켓에 의해 발사된 후 동경 128.2도, 적도 상공 약 35,800 km 고도의 정지궤도에 안착되었다. 이 후 궤도상시험 기간과 안정화 기간을 거쳐 2011년 4월 1일, 기상청은 위성자료 서비스를 시작하였다. 천리안위성의 기상영상기는 한반도 주변의 기상변화와 전 지구적 기후 변화 및 대기 운동을 감시하기 위해 실시간 관측 및 전송 시스템을 갖춘 탑재체이다. 이 기상영상기는 하루 8번의 지구 반면 영역과 각각 80번 내외의 북반구 및 한반도 영역을 관측하며, 이 자료는 지상에서 복사보정과 기하보정을 거친 후 위성을 통해 다시 사용자에게 배포된다. 천리안위성 기상영상기는 쉼 없이 관측하고, 일정 시간 이내에 그 자료를 배포해야 한다. 이러한 자료서비스는 운영시스템의 장애나 자연현상에 의한 자료 미수신 혹은 미처리가 발생할 경우 운영 결과 및 성과에 영향을 미친다. 이와 같은 장애에 대비해 국가기상위성센터는 이중화된 시스템을 구축했으며, 자료 백업 부기관으로서 한국항공우주연구원과의 사이트 이중화도 시행하고 있다. 그러나 정지궤도에 있는 위성과 태양 및 지구의 역학적인 관계에 따라 태양 전파 잡음의 영향인 태양간섭과, 위성 태양전지판 충전 장애를 일으킬 수 있는 위성식, 그리고 위성 자정 주변에 발생할 수 있는 태양광 침입 및 산란광 영향 등은 미리 예측되어야 하며, 이 시기 운영 방안 마련과 사용자 공지 등의 조치가 수반되어야 한다. 국가기상위성센터는 춘 추분 시기에 발생하는 이러한 태양 영향을 예측하고 검증했으며, 이 시기 위성 및 지상국의 효율적인 운영방안을 마련하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.527-531
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• 2007

하천내에서 작은 물고기의 국지적인 회유 또는 이동 습성은 먹이를 구하고, 산란 및 성장과 집단에서 분산하고, 위험으로부터 도피하는 것에 밀접한 연관이 있다. 하천의 합류부와 연결부에 제방(levee), 도로(road) 등이 설치되는 경우 일반적으로 암거형태의 인공수로로 상 하류를 연결되는데, 암거내 수리특성상 평수시 저유량, 고유속, 저수심의 수리특성을 보인다. 이러한 수리특성은 물고기가 이동하는데 장애(barrier)가 되어 생태적으로 하천내 종다양성 감소와 일부 어종의 멸종을 초래한다. 어도 설치시 설계기준에서 가장 주목할 부분은 어도를 이용할 대상어종의 범위와 유영능력이다. 하천설계기준(2005, 한국수자원학회)에서 제시된 물고기의 유영능력은 대부분 국외 어종을 대상으로 외국에서 실험한 결과를 이용하고 있다. 그러므로 이러한 기준이 국내 어종에 대해 적합한지에 대한 검토가 필요하다. 본 실험의 목적은 국지회유성인 피라미와 각시붕어가 인공수로를 통과할 때의 유영행동 중 소상성공율과 유영속력을 평가하고자 함이다. 유영행동의 실험방법은 Brett(1967)에 의해 제안된 2가지 방법인 증진유속방법과 고정유속 방법중에서 물고기의 이동경로와 소상능력을 확인하기에 용이한 고정유속방법을 사용하였다. 또한, 효과적인 실험을 위해 실험어종(피라미 100마리, 각시붕어 100마리)이 실험 중에 최적의 건강상태를 유지할 수 있도록 물고기의 적응 기간(24시간)과 실험 중 휴식기간을 두었다. 실험결과 체형이 방추형(fujiform)인 피라미의 경우 평균유속 $0.7{\sim}0.8m/s$구간에서 소상성공율이 61%에서 26%로 급격하게 하락하는 현상이 나타났다. 그리고 측편형(compressiform)의 체형을 가진 각시붕어의 경우 평균유속 0.4m/s에서 소상성공율이 25%로 나타났으며 그 이상의 유속에서는 10%이하로 나타났다. 실험어종의 이동경로를 분석한 결과 대부분 수로바닥에 밀착하여 최저유속구간을 이용하여 이동하는 것으로 나타났으며, 이동경로의 지점유속은 평균 유속의 70%정도로 나타났다. 실제 하천에 설치된 인공수로가 생태통로의 기능을 유지하기 위해서는 평상시 수리특성이 대상어종의 유영능력을 초과하지 않도록 설계되어야 한다. 특히, 하천에 설치된 인공수로의 길이가 $5{\sim}10m$정도일 경우라면 피라미의 소상 가능성을 50% 이상 확보하기 위해서는 평수시 설계유속이 0.7m/s를 초과하지 않아야 할 것으로 판단된다.

• Korean journal of applied entomology
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• v.38 no.2
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• pp.109-115
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• 1999

Morphological characteristics and life cycle of Udea ferrugalis (Hubner) attacking Angelica utilis were studied in 1995 and 1996. Egg of U. ferrugalis was oval-shaped with light-gray. Larva was milk white or light yellow color with 1.50-14.6 mm body length, depending on their developmental stages from 1st to 5th instar. Pupa were deep-brown with 8.2-9.7 mm length. Adults were brown color and body lengths were 10.1 mm and 8.3 mm and wing expanse lengths were 18.5 mm and 16.6mm with female and male, respectively. At 20$^{\circ}$C, each developmently periods was 5.81, 19.0, 3.46 and 1 l.0days with egg, larvae, pre-pupae, and pupae, respectively. Also adult longevitys were 10.13 for female and 9.8 days for male. Average number of egg were 238.5 and 248.8 at 20$^{\circ}$C and 30$^{\circ}$C, respectively. A total of 12 species host plants were identified in the outdoor observation in Chungbuk province.

• Korean journal of applied entomology
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• v.30 no.4
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• pp.258-264
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• 1991

Studies were carried out to investigate effects of temperature and photoperiod on diapause induction and of juvenile hormone III and 20-hydroxyecdysone treatment on diapausing adults of the alder leaf beetle, Agelastica coerulea Baly(Chrγsomelidae: Coleoptera). Its life cycle and ovarian development in adults were also observed. The beetle had one year life cycle with egg, larval, pupal and adult periods being 7-10, 19-21, 14-15 days and about 10 months, r respectively. All adults showed a diapause syndrome when the larvae were reared at $20^{\circ}C$ or $25^{\circ}C$ in combination of photoperiods of 16L/8D, 12L/12D, or 8L/16D. Their ovarioles did not s show any development of vitellogenesis before or during diapause and even when exposed at $15^{\circ}C$ after overwintering. When diapausing adults were treated with JH III they resumed feeding and laid several eggs and broke diapause condition temporally. But diapausing adults treated with 20-hydroxyecdysone did not show any response.

• Horticultural Science & Technology
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• v.29 no.5
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• pp.420-432
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• 2011

Population dynamics of greenhouse whitefly, Trialeurodes vaporariorum (Westwood), were modeled and simulated to compare the temperature effects of air and tomato leaf inside greenhouse using DYMEX model simulator (pre-programed module based simulation program developed by CSIRO, Australia). The DYMEX model simulator consisted of temperature dependent development and oviposition modules. The normalized cumulative frequency distributions of the developmental period for immature and oviposition frequency rate and survival rate for adult of greenhouse whitefly were fitted to two-parameter Weibull function. Leaf temperature on reversed side of cherry tomato leafs (Lycopersicon esculentum cv. Koko) was monitored according to three tomato plant positions (top, > 1.6 m above the ground level; middle, 0.9 - 1.2 m; bottom, 0.3 - 0.5 m) using an infrared temperature gun. Air temperature was monitored at same three positions using a Hobo self-contained temperature logger. The leaf temperatures from three plant positions were described as a function of the air temperatures with 3-parameter exponential and sigmoidal models. Data sets of observed air temperature and predicted leaf temperatures were prepared, and incorporated into the DYMEX simulator to compare the effects of air and leaf temperature on population dynamics of greenhouse whitefly. The number of greenhouse whitefly immatures was counted by visual inspection in three tomato plant positions to verify the performance of DYMEX simulation in cherry tomato greenhouse where air and leaf temperatures were monitored. The egg stage of greenhouse whitefly was not counted due to its small size. A significant positive correlation between the observed and the predicted numbers of immature and adults were found when the leaf temperatures were incorporated into DYMEX simulation, but no significant correlation was observed with the air temperatures. This study demonstrated that the population dynamics of greenhouse whitefly was affected greatly by the leaf temperatures, rather than air temperatures, and thus the leaf surface temperature should be considered for management of greenhouse whitefly in cherry tomato grown in greenhouses.

• Korean Journal of Poultry Science
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• v.36 no.2
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• pp.117-123
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• 2009

This work was conducted to evaluate the effects of induced-molting methods on visceral organs and blood stress indicators in laying hens. One hundred fifty of 63-wk-old White Leghorn hens, with over 85% of egg production and $1.7\;{\pm}0.4\;kg$ of average weight, were used in this study. Treatments were control (non-molt treatment), feeding molt treatment (FM), and starving molt treatment (SM). There were 5 replicates of 10 hens for each treatment. All treatment groups were fed basal diet (15% CP and 2,700 kal/kg of ME) for two weeks as adaptation period. Heart weights were 8.2, 7.9 and 7.5 g in control, FM and SM, respectively. Liver and oviduct weights were decreased in both molting treatments compared with control (P<0.05). Corticosterone (CS) concentrations were 4.48, 4.47 and $4.66\;{\mu}g/mL$ in control, FM and SM at 61 weeks, respectively, but increased to 7.32, 7.11 and $7.71\;{\mu}g/mL$ at 62 weeks, respectively (P<0.05). Heterophil to lymphocyte ratios were 0.27~0.29 in all groups at 61 weeks, but increased to 0.97~1.03 in SM at 62 weeks. Both CS concentrations and H:L ratios in SM were greater compared with those for the other groups. These results suggest that hens in feeding molting program in hens are less stressed than those in starving molting one.

• Journal of Sericultural and Entomological Science
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• v.26 no.2
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• pp.11-15
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• 1984

To save the labour reguired for separation of copulated moth during egg Production, some of the chemicals available at the market were on screen test for easy separation of copulated moth of silkworm. The obtained results are summarized as following. 1. In a separation ratio of copulated moth along with a treating time, TCTFE(Trichloro-trifluoroethane) completely separated the copulated moth in 10 minutes. The combinations of TCTFE plus Acetone (87.5 : 12.5 V/V) and TCTFE plus Acetic acid (50 : 50 V/V) take 25minutes for the complete separation of copulated moth. Use of Acetic acid solution only makes 100% separation of copulated moth in one hour and foully minutes and non$.$treatment shows only 47.5% of separation in three and half hours. On the other hand. There is no statistical significance between TCTFE Plus Acetone and control in the egg productivity. 2. The combination of TCTFE Plus Acetone (87.5 : 12.5 V/V) does not infuluence the egg productivity of the moth, showing 443 grains for an average number of egg per moth out of which 417 grains are for the number of fertilized eggs while control shows 452 grains for an avarage number of egg/moth and 428 grains for the number of fertilized eggs. However a sing1e use of TCTFE and Acetic acid shows less egg productivity and number of ferilized eggs per moth, respectively as compared to those of the control. In particular, a single use of acetic acid makes an increase of number of non-egg prodncible moth and it seems to be brought due to a chemical damage. 3. In a rearing test of the egg laid by the chemical treated moth, there are no differences among the treatments in all of the useful characters of the larvae; larval duration, survival rate, cocoon yield, single cocoon weight, single cocoon shell weight and cocoon shell ratio. In these regards, it is recognized that TCTFE can be practically used for the separation of copulated moth and the combination of TCTFE and Acetone promote its efiectiveness on the separation of copulated moth.

• Korean Journal of Poultry Science
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• v.18 no.3
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• pp.151-159
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• 1991

As a part of investigation on causes of drop in egg production in domestic chicken breeding farm, bacteriological contamination on air, feed, drinking water and artificial insemination instruments of randomly selected three farms was surveyed. Total bacterial population in the air was very high in all of the chicken houses tested and was not significantly different among these farms . However, total bacterial counts in the air of the problem house having egg drop problem and colibacillosis was higher than normal house within the problem farm. Bacterial population in the assorted feed was low before or after administration on the normal farm while it was much more increased after administration than before administration on the problem farm. Bacterial population of the drinking water in the source of water supply was very low and has no differences among farms tested. Also, bacterial population in the normal farm was not significantly different between source of water supply and after administration. However, population of total bacteria and coliform bacteria after administration was increased. Bacterial population was much higher in the artificial insemination instrument of problem farm than normal farm. However, this bacterial population in the problem farm was decreased to those of normal farm after these instruments were sanitized.

• Korean Journal of Poultry Science
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• v.34 no.1
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• pp.9-14
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• 2007

This study was conducted to investigate the effects of coastal mud-flat bacteria origin protease supplementation on laying performance, nutrient digestibility and total protein concentration of serum in laying hens. A total of 252 laying hens were randomly allocated into three treatments with seven replications for eight weeks. Dietary treatments included 1) CON (basal diet), 2) PRO1 (basal diet + 0.05% protease) and 3) PRO2 (basal diet + 0.1% protease). During the entire experimental period, hen-day egg production was not affected by treatments (P>0.05). Difference of yolk height was increased in PRO1 treatment compared with CON treatment (P<0.05). Difference of egg weight was increased in PRO2 treatment compared with CON and PRO1 treatments (P<0.05). Shell quality, yolk color unit, haugh unit and egg yolk index were not affected by treatments (P>0.05). DM digestibility was improved in CON and PRO2 treatments compared with PRO1 treatment (P<0.05). N digestibility was improved in PRO2 treatment compared with CON treatment (P<0.05). Total protein concentration in serum were not affected by treatments (P>0.05). In conclusion, mud flat bacteria origin protease was effective for improving egg weight, yolk height and nutrient digestibility in laying hens.

• Korean Journal of Poultry Science
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• v.35 no.2
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• pp.183-190
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• 2008

This study was conducted to investigate the effect of feeding diets supplemented with ${\beta}-glucan$ products on the performance, small intestinal microflora and immune response in laying hens. The ${\beta}-glucan$ products used in the experiment were $BetaPolo^{(R)}$ ; soluble ${\beta}-glucan$ of microbial cell wall origin, $HiGlu^{(R)}$ ; microbial cell wall origin, $OGlu^{(R)}$ ; oat origin, $BGlu^{(R)}$ ; barley origin. A total of 720 Hy-Line Brown laying hens of 40wks old were divided into 5 dietary treatments : T1 ; Control( C), T2 ; $BetaPolo^{(R)}$, T3 ; $HiGlu^{(R)}$, T4 ; $OGlu^{(R)}$, T5 ; $BGlu^{(R)}$. Each treatment was replicated 4 times with 36 birds/replicate housed in 2 bird cages, and arranged according to completely randomized block design. Feeding trial lasted 40ds under 16 h lighting regimens. There were significant differences among treatments in hen-house egg production feed intake and feed conversion. HiGlu treatment was significantly higher than OGlu treatments in hen-house egg production. ${\beta}-glucan$ supplemented treatments were lower than the control in feed intake and feed conversion ratio. All ${\beta}-glucan$ supplemented treatments were significantly higher than the control in eggshell strength. Eggshell color and Haugh unit tended to be lower in the supplemented group than the control. IgY concentration was not significantly affected by treatments. At $5^{th}$ week of experiment, however, IgY concentration tended to increase in the supplemented groups. Among the leucocytes parameters, WBC, heterophil, lymphocytes, monocyte and eosinophil concentration were lower in the supplemented groups than those of the control. Among erythrocytes, HCT(hematocrit) and MCV(mean corpuscular volume) were significantly affected by treatment. MCV of supplemented groups were higher than that of the control. Immunoglobulin concentrations in the birds were not significantly different among treatments. However, IgA concentration tended to be low in the supplemented groups than the control. The cfu of small intestinal microflora were not significantly different among treatments, but that of Cl. perfringens tended to be lower than the control. The result of this experiment indicateted that feeding ${\beta}-glucan$ to laying hens improve feed conversion ratio and eggshell strength. Also intestinal microflora and immune responses are modified.