• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집E
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• pp.450-455
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• 2001

An analytical study is made of transient adjustment process of an initially stationary, stably-stratified fluid in a square. The boundary walls are highly-conducting. The overall Rayleigh number $R_a$ is large. Considerations are given to both opposing (${\delta}w/{\delta}T>0$) and cooperating (${\delta}w/{\delta}T<0$) configurations. The flow character in opposing configuration can be classified into (a) a forced-convection dominaut mode (${\delta}w/{\delta}T>1/\sqrt{2}$), (b) a buoyancy-convection dominant mode ($0<{\delta}w/{\delta}T<1/\sqrt{2}$), and (c) a static mode (${\delta}w/{\delta}T{\cong}1/\sqrt{2}$). Global evolutionary processes are depicted. and physical rationalizations are provided.

• 한국식품영양학회지
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• 제36권1호
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• pp.50-57
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• 2023

This study was designed to evaluate antihyperglycemic and antihyperlipidemic effects of ethanol extracts of Taraxacum mongolicum(T.m.) on streptozotocin (STZ)-induced diabetic rats. Sprague-Dawley rats were randomly assigned to five groups: normal (NC), STZ-control (DC), and three experimental groups. Diabetes was induced in Sprague-Dawley rats with a single intravenous injection [45 mg/kg body weight (b.w.)] of STZ. An ethanol extract of T.m. was orally given to diabetic rats for 14 days. Three experimental groups were additionally treated with T.m. extract at doses of 1 g/kg b.w./day for T.m.-1, 2 g/kg b.w./day for T.m.-2, and 3 g/kg b.w./day for T.m.-3. Oral administration of T.m.-2 significantly increased their body weights. T.m.-1 and T.m.-2 significantly decreased aspartate aminotransferase (AST) levels than DC. T.m.-1 and T.m.-2 group significantly decreased blood glucose levels. Total cholesterol, triglycerides, and free fatty acids were significantly decreased whereas high-density lipoprotein cholesterol was significantly increased in groups treated with T.m. extract than those in the DC group. These results support the fact that administration of T.m. extract can reduce hyperglycemia and hyperlipidemia risk in diabetic rats.

• 한국초지조사료학회지
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• 제40권4호
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• pp.236-243
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• 2020

본 연구는 사료용 벼 사일리지의 사료가치를 평가하고 반추위 발효성상을 이용하여 사료용 벼 사일리지와 배합사료의 적정 비율을 조사하고자 하였다. 사료가치 평가는 AOAC(2019)에 따라 분석하였고, 영양소 소화율 예측은 NRC(2001)의 수식을 기반으로 산출하였다. In vitro 반추위 발효시험은 총 6개의 시험구로 구성되었고, 반추위 pH, 가스생성량, 암모니아태 질소 및 휘발성 지방산을 측정하였다:T1(100:0), T2(60:40), T3(40:60), T4(20:80), T5(10:90), T6(0:100). 영양소 소화율 시험에서는 사료용 벼 사일리지 비율에 따라 40:60(W40), 20:80(W20) 및 10:90(W10)로 나누어 수행하였다. 사료용 벼 사일리지의 조단백질, 조지방 및 NDF 함량은 각각 12.29%, 1.67%, 59.79%로 측정되었다. 또한 NRC(2001)을 이용한 사료용 벼 사일리지의 TDN 예측 결과는 51.49%로 나타났다. 반추위 발효 in vitro 결과, 가스생성량과 총 휘발성 지방산생성량은 T4, T5 및 T6에서 다른 시험구보다 유의적으로 높았다(p<0.05). 초산과 AP ratio도 T4, T5 및 T6에서 유의적으로 높게 나타났다(p<0.05). 프로피온산 및 낙산에서는 사료용 벼 사일리지와 배합사료의 비율의 변화에 따라 유의적인 차이를 보였다(p<0.05). 건물 및 조단백 소화율은 W40에서 유의적으로 낮은 결과를 보였으나(p<0.05), W20 및 W10은 유의적 차이가 없었다. 따라서 사료용 벼 사일리지는 사료로서 가치가 있다고 판단된다. 또한, 사료용 벼 사일리지와 배합사료의 급여비율을 20:80하는 것이 반추위 발효 및 영양소 소화를 저해하지 않는 수준에서 농가의 경제성에도 긍정적일 것으로 생각된다.

• 산업기술연구
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• 제27권B호
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• pp.59-64
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• 2007

This study introduces an environmental noise evaluation procedure and results for a wind turbine (W/T) system. Test and evaluation are required by the international standard IEC 61400-11 in the aspect of environmental effect. Test and evaluation are performed on U-50 WT model which is first developed by the domestic W/T manufacturer. W/T test model is under operation in Daekwanryung wind test site. An integrated monitoring system in the test site is utilized for the evaluation. With the noise signal, meteorological data and W/T operational data are monitored in real time by the integrated monitoring system using LabVIEW. From the measured noise data, acoustic power level are estimated and compared with those of other similar size WT under the wind speeds required by international standard.

• 한국전자파학회논문지
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• 제13권5호
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• pp.451-458
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• 2002

6-18 GHz 주파수대역에서 사용되는 흡수형의 SP3T 및 SP8T 스위치 모듈을 설계 및 제작하였다. 스위치 모듈에 사용된 MMIC 칩의 에피구조는 저 손실과 고 전력용으로 설계되었다. 최대입력전력은 SP3T 스위치 모듈이 2 W이고 SP8T 스위치 모듈이 1 W이다. 200 nsec의 고속 스위칭을 위한 구동회로를 모듈에 내장하였다. 모듈의 최대삽입손실은 SP3T 및 SP8T에 대해 각각 2.8 dB, 4.2 dB로 측정되었다. 입ㆍ출력포트간 분리도는 모두 55 dB 이상을 얻을 수 있었다. 두 스위치 모듈은 전자전 시스템에 적용하기 위한 관련 환경시험을 모두 통과하였다.

• 논리연구
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• 제9권2호
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• pp.1-30
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• 2006

This paper investigates algebraic semantics for some weak Boolean (wB) logics, which may be regarded as left-continuous t-norm based logics (or monoidal t-norm based logics (MTLs)). We investigate as infinite-valued logics each of wB-LC and wB-sKD, and each corresponding first order extension $wB-LC\forall$ and $wB-sKD\forall$. We give algebraic completeness for each of them.

• ALGAE
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• 제17권3호
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• pp.195-199
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• 2002

We investigated the association of Chlorella vulgaris and E. coli W9110 in removal of total organic carbon with the lab-scaled continuous river water flow system (CRWFS). Artificial wastewater was applied at two levels of organic carbon concentration; 1,335 $mg{\cdot}l^{-1}$ in the treatment (T)-1 and 267 $mg{\cdot}l^{-1}$ in T-2. The highest densities of C. vulgaris were $8.3{\times10^6\;cells{\cdot}ml^{-1}$ in T-1 and $6.9{\times}10^6\;cells{\cdot}ml^{-1}$ in T-2. The maximum densities of E. coli W3110 were $2.0{\times}10^8$ clony forming unit (CFU)${\cdot}ml^{-1}$ in T-1 and $3.9{\times}10^8\;CFU{\cdot}ml^{-1}$ in T-2. The densities increased during the first 11 days in T-q and 4 days in T-2, and decreased rapidly till 35th day, then increased slightly afterwards. This trend was prominent in T-2. It was inplied that wider range of nutrients was required in the growth of heterotrophic bacteria in T-2 than in T-1. The algal biomass should be increased effectively for the successful removal of organic carbon.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제7권1호
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• pp.85-89
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• 2007

Many authors considered the computational aspect of sup-min convolution when applied to weighted average operations. They used a computational algorithm based on a-cut representation of fuzzy sets, nonlinear programming implementation of the extension principle, and interval analysis. It is well known that $T_W$(the weakest t-norm)-based addition and multiplication preserve the shape of L-R type fuzzy numbers. In this paper, we consider the computational aspect of the extension principle by the use of $T_W$ when the principle is applied to fuzzy weighted average operations. We give the exact solution for the case where variables and coefficients are L-L fuzzy numbers without programming or the aid of computer resources.

• Asian-Australasian Journal of Animal Sciences
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• 제32권10호
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• pp.1603-1610
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• 2019

Objective: The purpose of this study was to investigate the effect of fermented spinach derived nitrite and sodium nitrite on cured pork loin. Methods: The following treatments were prepared using brine (8% [w/v] salt): Control (-), no nitrite added; Control (+), 0.08% (w/v) sodium nitrite brine; T1, 0.04% (w/v) nitrite fermented spinach juice in 0.04% (w/v) sodium nitrite brine; T2, spinach juice in 0.04% (w/v) sodium nitrite brine; T3, 0.04% (w/v) nitrite fermented spinach juice used as sodium nitrite free brine; and T4, spinach juice used as sodium nitrite free brine. T2 and T4 were incubated to allow to reduce nitrate to nitrite. Results: Spinach juice did not affect cooking loss and pH but negatively influenced flavor and overall acceptability (p<0.05). T1 samples containing synthetic and natural nitrites showed the highest redness values. Spinach juice negatively affected volatile basic nitrogen; however, thiobarbituric acid reactive substance values of T1 and T3 were similar to those of controls (+) (p>0.05). Residual nitrite content decreased with decreasing synthetic nitrite levels. T1 and control samples showed no significant differences in overall acceptability (p>0.05). Conclusion: Thus, combined synthetic and natural nitrites improved the quality of cured pork loin.

• 한국양식학회지
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• 제10권1호
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• pp.25-32
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• 1997

코끼리조개의 인공종묘생산 기술개발의 일환으로 성숙된 모패를 절개법에 의하여 인공수정시켜 난 발생 및 유생의 발달과정을 관찰한 결과를 요약하면 다음과 같다. 코끼리조개의 난은 분리침성란으로 나타났으며, 방란직후 알의 모양은 타원형이나 수정이 되면 직경 $70\mu$m의 구형으로 된다. 수정난의 발생은$ 11^{citc}C$에서 4시간 후 4세포기로 되고, 2일이 지나면 담륜자 유생(trochophore larvae), 수정 후 3일째에는 D상 유생, 23일째에는 각정기, 36일째에는 성숙유생으로 되었다. 수온(w)에 따른 각 단계별 소요시간(t)의 관계를 보면, 8세포 : 1/t=0.0209 w-0.1167 (r=0.9967) 포배기 : 1/t=0.0055 w-0.0192 (r=0.9825) 담륜자기 : 1/t=0.0034 w-0.0155 (r=0.9907) D상 유생기 : 1/t=0.0014 w-0.0023 (r=0.9843) 상기 식에서 산출된 코끼리조개의 생물학적 기초수온은 3.82$^{\circ}C$였다.