• Korean Journal of Poultry Science
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• v.29 no.3
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• pp.213-223
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• 2002

This study was conducted to investigate the influence of feeding various Lactobacillus on production performance, nutrients digestibility, intestinal microflora, and fecal $NH_{3}$ gas emission in laying hens. Three hundred and sixty ISA Brown layers, 21 weeks of age, were randomly allotted to nine treatments, with low replicates per treatment. Nine treatments consisted of Control(no Lactobacillus), Lactobacillus crispatus avibrol(LCB: KFCC-11195), Lactobaciilus reuteri avibro2(LRB: KFCC-11196), Lactobacillus crispatus avihenl(LCH: KFCC-11197), Lactobacillus vaginalis avihen2(LVH: KFCC-11198). Each Lactobacillus was added at two levels ($10^{4}$and $10^{7}$ cfu/g diets). Egg production, and egg weight were measured daily. A metabolism trial was conducted following the 12-week feeding trial, during which egg qualities, intestinal microflora and fecal $NH_{3}$ gas emission were examined. Egg production and daily egg mass improved significantly by the addition of various Lactobacillus(P<0.05), of which effect was more notable during the latter part of the feeding trial. But, no significant differences were found among Lactobacillus strains and between two levels of supplementation. Egg weight and feed intake showed no difference among all treatments. Feed conversion ratio of birds fed lactobacillus was significantly improved compared to that of the Control(P<0.05), but not different among lactobacillus treatments. Digestibility of crude protein, ether extract and crude ash improved significantly in lactobacillus treatments(P<0.05). However, there were not statistically different by adding levels and strains. Total counts of Lactobacillus spp. in ileum of layers fed Lactobacillus were significantly higher than that of the control, but no consistent trend was found in cecum. There were no significant differences in intestinal yeast and anaerobes counts among all treatments. The Lactobaciilus supplementation did not exert my effect on the eggshell quality and Haugh unit. Fecal $NH_{3}$ gas emission decreased significantly in Lactobacillus treatments, and showed no difference between the two supplementation levels. From the result of this study, it could be concluded that dietary supplementation of Lactobacillus, regardless of their species, Improves the laying performance and decreases the fecal ammonia gas emission. The proper level of supplementation appears to be $10^{4}$ cfu/g of diet.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.6
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• pp.179-190
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• 2015

This study was carried out to suggest fundamental concepts and data ideas for biodiversity and confrontation strategy on global environmental changes by analyzing geomorphic milieu and geotop in Mt. Jeombong experimental forest. Elements of landform were classified as landform sets by scale. Scale for classification could be decide on four categories. We could classify landforms which scale zero is seven elements, scale one is twelve elements, scale two is fifteen elements, scale three is twenty nine elements. Especially mountain wetlands were classed as valley and channel types in Mt. Jeombong. Geotop by clustering methods could be four spatial units as 2, 3, 5, and 7 classes, and analyzed geodiversity as landform sets for explanation of vegetation distribution. Rate of rise of temperature was $0.031^{\circ}C$ per year, change ratio was increased $1.25^{\circ}C$, and also precipitation was increased 320mm during forty year(from year 1973 to year 2012). The result of this research can be affordable to provide information for forest management of mountainous areas.

• Journal of the Korean Geotechnical Society
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• v.18 no.4
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• pp.285-294
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• 2002

Embankment Piles, which is subjected to damage due to lateral movement of soft ground, can be classified into pile slab, cap beam pile, and isolated cap pile according to the installation pattern of pile cap. In the cap beam pile and the isolated cap pile method, the soil arch is developed by the different stiffness between pile and soil, and most embankment loads are transferred into embankment piles through soil arch. In these two methods, the difference of soil arch is that the soil arch of the cap beam pile method develops like the arch from of tunnel between cap beams and the soil arch of the isolated cap pile method develops like dome between isolated caps. Therefore, theoretical analysis methods on soil arching effect of the cap beam pile and the isolated cap pile method were respectively proposed according to their own arch form considering the limiting equilibrium of stresses in a crown of soil arch. And a series of model tests were performed both to investigate the load transfer by soil arching in fills above embankment piles and to verify the reliability of the theoretical analysis.

• Solar Energy
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• v.17 no.2
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• pp.35-42
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• 1997

Thermal diode is a device which allows heat to be transferred in one direction by convection due to difference of density of fluid, and blocks heat flow in the opposite direction. Vertical plate for heat collection and radiation are of utility for design of thermal diode. It was considered the transient and steady state of air filled thermal diode with guide vane which combined rectangular and parallelogrammic shape enclosures. $Gr^*$ was kept constantly on $1.11{\times}10^{10}{\sim}1.4{\times}10^{10}$ and error range was ${\pm}3%$ during the experiment. Nu was examined when inclined angle are $15^{\cir\c}\;and\;45^{\circ}$ and, also the experiments was carried out with and without guide vane as well. Specially, Nu was linearly increased due to increase of $Gr^*$, and the effect of guide vane and dimensionless channel depth was sensitive. Developed state of temperature began at dimensionless time $0.5{\sim}0.6$ due to variation of inclined angle, which is characteristic of system.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.9
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• pp.711-716
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• 2020

Injection visualization of heated mixed simulant droplets based on hydrocarbon fuel was performed under supercritical state environment. Mixed simulant consisted of Decane and Methylcyclohexane with different critical pressure and critical temperature. Flows injected into the supercritical state environment created droplet by Rayleigh breakup mechanism, and the Oh number and Re number were determined to confirm the breakup area. The temperature of the mixed simulant varied from Tr=0.49 to Tr=1.34. The flow rate was maintained at 0.7 to 0.8 g/s. Droplet became shorter in breakup length as heated and into a lumped form. Second droplet was formed and when Tr=1.34, the phase was not visible in the supercritical state with local unsteady flow.

• The Journal of the Korea Contents Association
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• v.14 no.12
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• pp.629-638
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• 2014

Objective of this study is to be utilized as foundational data of expression methods and to increase children's dream and imagination by researching and analyzing differences of imaginative reaction from patterns of imaginative activities and verbal response for the expressive methods of illustrations. Study subjects are 253 children aged from six to seven years old, and four different types of research tool of which are screens with simple pattern, realistic pattern, omitted pattern and indirect pattern has been used in the empirical survey conducted over two times. Result from provided research tools has shown that difference of diversity can be observed from patterns of imaginative activities and verbal reaction patterns. Especially, in terms of imaginative activities, structural and creative imagination responses can be observed from screens with simple, omitted patterns and indirect and metaphorical patterns compares to screens with simple patterns and direct, realistic patterns, and positive affection to children's dream and creativity and imagination can be found from the result of high imaginative response observed from patterns of verbal reaction.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.81-81
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• 2018

곤달비는 국화과에 속하는 대표 산채로 쌈용으로 많이 소비되고 있다 곤달비를 경관농업의 소재로 6차산업화하기 위한 친환경 생산기술을 개발코자 하였다 곤달비의 재배 중 흰가루병 발생은 가장 큰 문제로 자생식물과의 혼식을 통해 병의 진행 억제효과를 구명코자 하였다 천궁과 당귀를 곤달비와 함께 인공상토로 채운 화분에 1주씩 혼식하였고 곤달비만 심은 대조구를 두었다 흰가루병 접종은 포자를 곤달비에 발생시킨 후 접종하였다 약 7일의 흰가루병 발생기를 거친 후 6월 4일~6월 21일까지 2~3일 간격으로 진행률을 조사하였다 조사결과는 병의 진행률을 계량하기 위해 효율적인 AUDPC(Area Under the Disease Pogress Curve) 방법을 적용하여 분석하였다 천궁 당귀와 혼식한 결과는 곤달비의 흰가루병은 동시에 발생하였다 곤달비만 심은 대조구는 병 발생 후 5일 간 가파르게 증가하였으나 천궁과 당귀와 혼식 처리구는 완만한 증가세를 보였다 6월 21일의 AUDPC 수치와 비율은 대조구가 602.3(1.00), 천궁 혼식구가 265.8(0.53), 당귀 혼식구는 226.1(0.45)로 혼식구가 대조구에 비해 50% 이하의 진행률을 나타냈다 통계처리 결과 대조구와 혼식구 간 1%의 유의성을 나타냈다 당귀가 가장 높은 억제율을 보였으며 이러한 원인에 대한 추가 분석이 요구된다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.267-274
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• 2009

Breakup and spray formation of pressure-swirl liquid jets injected into a low-speed convective-flow are experimentally investigated. Effects of the cross-flows on the macroscopic and microscopic spray parameters are optically measured in terms of jet Weber number and liquid-to-gas momentum ratio. The liquid stream undergoes Rayleigh jet breakup at lower jet Weber numbers and a liquid sheet isn't formed because of the weak radial velocity in the swirl jet. At higher jet Weber numbers, the macroscopic spray parameter is a very weak function of the momentum ratio but the effect of the convection on the microscopic spray parameter is significant through the secondary breakup with increasing in the liquid-to-gas momentum ratio. The convective-flow promotes bag/plume breakup and the spray formation, and its effect is more distinct at higher momentum ratio.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2006.05a
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• pp.164-169
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• 2006

본 연구는 가정용 가스 보일러의 배기가스 유동특성을 전산유체역학을 이용하여 정밀 분석하고 CO 검지 장치의 최적화 설계를 결정하는 것을 목적으로, CFD 상용코드 FLUENT 6.2를 이용하였다. 배기가스 포집위치에서 가스 유속의 균일성과 CO농도 검출기에서의 속도가 주요 성능 인자이며 포집기의 위치, 포집구멍의 크기 및 배기가스의 유량을 주요 변수로 선택하였다. 포집기의 위치는 배기부의 상부와 하부인 두가지의 경우이고 두 경우의 배관 높이 차이는 10 mm이다. 포집구멍의 직경 변화는 3 mm, 4 mm 및 5 mm인 세가지 경우이다. 마지막 변수인 배기가스의 유입속도는 20,000 kcal/hr용량의 k사 가스 보일러가 공기비 1.1일 경우에 정상 연소시 0.5 m/s임을 알았고 저부하와 고부하일 경우를 고려해서 0.3 m/s, 0.5 m/s 및 0.7 m/s의 세가지 경우를 변수로 결정하여 총 18가지 형태의 대상을 전산유체 역학을 통해서 분석하였다. 궁극적인 목표였던 배기가스의 균일성은 한가지 경우를 제외 하고는 만족할만한 결과를 얻었기 때문에 CO검지 장치가 위치할 곳에서의 속도 및 포집구멍의 크기가 CO농도 검출기 유속의 주요 인자라 할 수 있다. 결론적으로 포집구멍의 크기가 5 mm인 6가지 경우 중에서 두가지 경우는 검지장치의 유효속도를 초과하였고 포집구멍의 크기가 3 mm인 경우는 검지장치의 유입 속도가 상대적으로 작으므로 포집구멍의 크기는 4 mm가 적합한 것으로 판단하였다.

• The Journal of the Korea Contents Association
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• v.11 no.10
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• pp.165-175
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• 2011

This study aims to analyze and compare the difference of preference to realistic and fantastic expressions presented in the illustrations of children's picture books. The subject of this study is set for 52 seven-year-old kindergarten students, including 26 boys and 26 girls, in Cheonan. Two times of researches on their preferences were made on the basis of data collection through individual interviews and self-regulatory questionnaires. A children's picture book, which best demonstrates both realistic and fantastic expressions, was selected as a research tool for such questionnaire from the ones produced and printed within Korea, which either are listed in the Recommended Book List of Children's Book Research Association or received any international award. The result shows that both boys and girls prefer fantastic expressions to realistic ones. It was also found that girls tend to prefer realistic expressions that the boys do. Nevertheless, there definitely was a limitation in thorough analysis by region or age, as they tended to show different responses when they were provided with a picture book with similar theme and story, but different form of expression.