• 한국해안·해양공학회논문집
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• 제26권4호
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• pp.207-216
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• 2014

총유기탄소(TOC)는 해양의 탄소순환 연구분야에서 직접적인 생물학적 지표로 이용되는 중요한 인자다. 가용한 TOC 자료가 상대적으로 화학적산소요구량(COD) 자료 보다 부족하기 때문에 COD 자료를 활용하여 TOC 자료를 추정할 수 있다. COD를 TOC 로의 변환 시 TOC 추정에 직접적으로 영향을 미치는 COD 관측자료에 포함된 이상자료의 탐지와 적절한 처리는 합리적이고 객관적으로 수행되어야 한다. 본 연구에서는 국내 연안해역에서 관측된 염분, COD 및 TOC 자료에 대한 최적회귀모형을 제시하였다. 최적회귀모형은 이상자료와 영향자료를 여러 가지 탐색방법으로 진단하여 제거 전 후의 자료 개수 변화, 변동계수 및 RMS 오차를 비교 및 분석하여 선택하였다. 연구수행 결과, Cook의 진단방법과 SIQR의 boxplot 방법을 조합한 방법이 가장 적절한 것으로 파악되었다. 최적 회귀 함수는 TOC(mg/L) = $0.44{\cdot}COD(mg/L)+1.53$ 이고, 결정계수는 0.47 정도로 나타났으며, RMS 오차는 0.85 mg/L이다. RMS 오차와 지레계수(leverage values)의 변동계수는 이상자료 제거 전에 비하여 각각 31%, 80%로 크게 감소되었다. 본 연구에서 제시된 방법을 통해 COD와 TOC 관측자료에 포함된 이상자료와 영향자료의 과도한 영향을 진단 및 제거하였기 때문에 보다 적절한 회귀곡선식을 제시할 수 있었다.

• 한국가금학회지
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• 제9권1호
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• pp.1-16
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• 1982

최근 육계의 체지방 과다축적현상은 큰 문제로 되어 있다. 이는 육계가 생리적요구량 이상으로 에너지를 섭취하기 때문에 일어난 현상이다. 많은 문헌들을 종합하여 보면 육계의 품종, 계통, 성, 연령, 사료조건, 운동정도, 환경온도 및 사육방법 등이 체내 지폐축적에 영향을 미치는 요인인 것 같다. 이들 요인들은 지방조직의 지방세포의 수와 크기를 좌우하는 것이 다. 육계를 도살하지 않고 체내 지방축적량을 추정하기 위한 여러 가지 생체조사측정치 중에서 흉부우역의 피층두께와 그의 지방함률이 복강지방량과 비교적 높은 상관을 보이고 있지만, 이들의 상관계수는 체지방량 추정에 이용할 수 있을 정도로 높은 것은 아니다. 대부분의 보고들은 체중이 큰 쪽으로 선발해 나갈 때 주어진 일령에서 체지방량도 증가되고 있으나 일부 보고들을 보면 체중 위주의 선발을 하여가도 같은 체중에선 지방축적량에 변화가 없다. 한편 사료효율이 좋은 쪽으로 선발하여 갈 경우는 체지방 축적량이 줄어들고 반대로 단백질과 수분함량이 높아진다. 따라서 체중위주의 선발이 반드시 포만 현상을 초래한다고 결론하기는 어려우나, 사료효율 개선방향의 선발은 포만현상을 완화시킨다고 결론할 수 있을 것 같다.

• 한국측량학회지
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• 제37권4호
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• pp.267-277
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• 2019

사진측량과 컴퓨터비전 분야는 카메라에서 촬영된 영상에서 3차원 좌표를 결정하는 것은 동일하지만 두 분야는 카메라 렌즈왜곡 모델링 방법과 카메라 좌표계의 차이점으로 인하여 서로 간에 직접적인 호환이 어렵다. 일반적으로 드론 영상의 자료처리는 컴퓨터비전 기반의 소프트웨어를 이용하여 번들블록조정을 수행한 후 지도제작을 위해서 사진측량 기반의 소프트웨어로 도화를 수행하게 된다. 이때 카메라 렌즈왜곡의 모델을 사진측량에서 사용하는 수식으로 변환해야 하는 문제에 직면하게 된다. 이에 본 연구에서는 사진측량과 컴퓨터비전에서 사용되는 좌표계와 렌즈왜곡 모델식의 차이점에 대하여 기술하고 이를 변환하는 방법론을 제안하였다. 카메라 렌즈왜곡 모델의 변환식의 검증을 위해서 먼저 렌즈왜곡이 없는 가상의 좌표에 컴퓨터비전 기반의 렌즈왜곡 모델을 이용하여 렌즈왜곡을 부여하였다. 그리고 나서 렌즈왜곡이 부여된 사진좌표를 이용하여 사진측량 기반의 렌즈왜곡 모델을 이용하여 왜곡계수를 결정한 후 사진좌표에서 렌즈왜곡을 제거하여 원래의 왜곡이 없는 가상좌표와 비교하였다. 그 결과 평균제곱근거리가 0.5픽셀 이내로 양호한 것으로 나타났다. 또한 사진측량용 렌즈왜곡 계수를 적용하여 정밀도화 가능여부를 판단하기 위해서 에피폴라 영상을 생성하였다. 생성된 에피폴라 영상에서 y-시차의 평균제곱근오차가 계산한 결과 0.3픽셀 이내로 양호하게 나타났음을 알 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권1호
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• pp.46-52
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• 2000

Two experiments were conducted to determine ileal digestibilities for the amino acids contained in rapeseed meal using the regression technique and then applying the values obtained, in a growth trial, using growing-finishing pigs. For the digestibility trial, four 20 kg crossbred $(Yorkshire{\times}Landrace{\times}Beijing\;Black)$ barrows were fitted with simple T-cannula in the terminal ileum. After recovery, the barrows were fed one of four experimental diets according to a $4{\times}4$ Latin Square design. The pigs were fed corn-soybean meal based diets supplemented with 0, 25, 50 or 75% rapeseed meal. For the growth trial, 80 crossbred $(Yorkshire{\times}Landrace{\times}Beijing\;Black)$ growing pigs $(20{\pm}2.4kg)$ were fed corn-soybean meal diets supplemented with 0, 3, 6, 9 or 12% rapeseed meal. Four pens (2 gilts and 2 castrates) were assigned to each treatment. With the exception of isoleucine and methionine, the digestibility coefficients for the indispensible amino acids declined as the level of rapeseed meal in the diet increased. There was little agreement between the amino acid digestibilities determined with the regression technique and values previously published for rapeseed meal. During the growing (22-42 kg) period, the addition of rapeseed meal had no significant effects on gain, feed intake or feed conversion. During the finishing period (58-91 kg), daily gain was not affected by rapeseed meal inclusion but feed conversion declined (p<0.04) as the level of rapeseed meal in the diet increased.

• Asian-Australasian Journal of Animal Sciences
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• 제21권8호
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• pp.1171-1177
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• 2008

The performance of growing rabbits fed Ruzi grass (Brachiaria ruziziensis), head lettuce (Lactuca sativa) residue, Mimosa pigra and water spinach (Ipomoea aquatica) was studied in an experiment using 64 rabbits (4 males and 4 females per treatment) of 2 breeds, New Zealand White and a crossbred between New Zealand White and native breed. The rabbits had an average initial weight of 668 g, were about 6 weeks old and were housed in individual pens. The foliages were fed ad libitum and a commercial concentrate was fed at a restricted level of 2% of body weight on a dry matter (DM) basis. In the digestibility experiment, the rabbits, 4 per foliage and males only, were fed the same foliages as in the growth experiment but without concentrate. Daily weight gain was lower in the group fed Ruzi grass, 14.8 g/d (p<0.001) compared to 17.6, 18.5 and 18.4 g/d for head lettuce, Mimosa pigra and water spinach, respectively. Feed intake and feed conversion ratio were lowest for the rabbits fed water spinach, 66 g DM/d and 3.6 kg DM/kg live weight, respectively. The New Zealand White breed had a higher daily gain than the crossbred rabbits (p<0.05), 18.0 and 16.7 g/d, respectively. There were no significant differences in feed intake, growth or feed conversion ratio due to sex. The digestibility coefficients of DM, organic matter, crude protein, crude fiber, neutral detergent fiber and acid detergent fiber were significantly lower (p<0.001) in the rabbits fed Ruzi grass. Breed and sex had no effect on digestibility. In conclusion, feeding head lettuce residue, Mimosa pigra and water spinach resulted in higher growth rate and digestibility than feeding Ruzi grass and can be recommended as alternative feeds.

• 한국미생물·생명공학회지
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• 제20권1호
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• pp.61-67
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• 1992

유기용매 이상계에서의 thermolysin을 사용하여 아스파탐 전구체 합성시 pH, 온도, 기질농도, 그리고 유기용매상에 대한 수용액상의 부비피 ($\alpha$)등의 변화에 따른 기질의 분해 반응, 효소의 안정성, 그리고 Z-APM 합성에 미치는 복합적인 영향을 조사함으로써 반응조건의 최적화를 도모하였다. 유기용매 이상계에서의 L-PM.HCL의 자연분해는 수용액에서보다 훨씬 느리게 일어나며, 또한 $\alpha$가 증가할 수록 분해속도가 감소하는 것을 알 수 있었다.

• Journal of Pharmaceutical Investigation
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• 제31권3호
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• pp.143-150
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• 2001

Butyrolactone ester of ceftezole (CFZ-BL) was synthesized by esterification of ceftezole (CFZ) with ${\alpha}-bromo-{\gamma}-butyrolactone$. The synthesis was confirmed by spectroscopic analysis. CFZ-BL was more lipophilic than CFZ when the lipophilicity was assessed by partition coefficients between n-octanol and water at various pH. CFZ-BL itself did not show any microbiological activity in vitro, but serums taken after oral administration of CFZ-BL showed substaintial microbiological activity indicating that CFZ-BL is converted to microbiologically active metabolite, probably CFZ, in the body. The conversion was confirmed by in vitro incubation study, in which CFZ-BL was incubated in some body tissues of rabbit. Liver homogenate showed fastest conversion of CFZ-BL among the tissues tested (blood and intestine). Thus, CFZ-BL appeares to be rapidly metabolized in the liver to CFZ following oral administration. The metabolism process appears to be hydrolysis of the ester to CFZ, the parent drug of CFZ-BL. In vivo metabolism of CFZ-BL to CFZ was confirmed by analying CFZ by HPLC. CFZ concentration in the serum samples taken after oral administration of CFZ-BL were higher than those in the serum samples taken after oral administration of equivalent amount of CFZ. Oral bioavailability of CFZ-BL, a prodrug of CFZ, was 1.45-fold higher than that of CFZ in rabbits possibly due to enhanced lipophility and absorption of the prodrug.

• Asian-Australasian Journal of Animal Sciences
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• 제13권5호
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• pp.666-672
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• 2000

Two experiments were conducted to determine the ileal digestibility of the amino acids contained in sunflower meal using the regression technique and then applying the values obtained, in a growth trial, using growing-finishing pigs. For the digestibility trial, four 20 kg crossbred ($Yorkshire{\times}Landrace{\times}Beijing$ Black) barrows were fitted with simple Tcannula in the terminal ileum. After recovery, the barrows were fed one of four experimental diets according to a $4{\times}4$ Latin Square design. The pigs were fed corn-soybean meal based diets supplemented with 0, 25, 50 or 75% sunflower meal. For the growth trial, 80 crossbred ($Yorkshire{\times}Landrace{\times}Beijing$ Black) growing pigs (21.5 kg) were fed corn-soybean meal diets supplemented with 0, 5, 10 or 15% sunflower meal. Five pens (2 gilts and 2 castrates) were assigned to each treatment. With the exception of arginine and valine, the digestibility coefficients for the indispensible amino acids declined as the level of sunflower meal in the diet increased. During both the growing (21.5-49.1 kg) and finishing (49.1-90.3 kg) periods and over the entire experiment (21.5-90.3 kg), average daily gain declined in a linear manner (p<0.05) with increasing amounts of sunflower meal. Feed intake was not significantly altered while feed conversion declined in a linear manner (p<0.05) during the grower period only. When the entire experimental period was taken into account, there would appear to be little penalty in either growth or feed conversion for including sunflower meal at levels up to 10% of the diet. Therefore, the price relationship between sunflower meal and other high-protein feedstuffs may provide an excellant opportunity for pork producers to use sunflower meal in order to reduce feed costs.

• 한국작물학회지
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• 제35권2호
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• pp.156-164
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• 1990

A field experiment was conducted to study both the distribution characteristics of photosynthetically active radiation (PAR) in the soybean canopy and their relationships with dry matter production. The soybean cultivars 'Hwanggeumkong' and 'Paldalkong' were sown with the spaces of 60$\times$15cm and 30$\times$15cm at Suwon on May 20 and on June 20 in 1989. The ratio of PAR to the total shortwave radiation was estimated by the empirical equation derived from sunshine hours and direct incoming radiation. The functional relationships between the PAR interception and the leaf area index were expressed as a function of Beer's law. The extinction coefficients(k) in the functions ranged from 0.77 to 0.92. The values of k were greater at higher planting density, but they were affected neither by planting dates nor by varieties. The reflection ratio of PAR($\alpha$) was determined by the exponential function as below; $\alpha$=$\alpha$p-($\alpha$p-$\alpha$o) exp(-kㆍLAI) where $\alpha$p was the reflectance at the maximum LAI and $\alpha$o was that of the bare soil. The ap ranged from 0.025 to 0.035 and $\alpha$o ranged from 0.11 to 0.12, respectively. The reflected PAR ranged from 0.049 to 0.064 and the transmitted PAR ranged from 0.168 to 0.340 until maximum dry weights were observed. The slope from the linear regression of dry matter on absorbed PAR, conversion efficiency, ranged from 1.30 to 2.3g MJ$^{-1}$ during the growing season until maximum dry weight was reached. The total dry matter yield above ground (TDM) increased with the increases in the conversion efficiency. TDM was higher in Hwanggeumkong than Paldalkong and higher in the space of 30$\times$15cm than 60$\times$15cm, Paldalkong showed higher harvest index than Hwanggeumkong. than Hwanggeumkong.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권1호
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• pp.99-102
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• 2005

Organic solvents are widely used in biotransformation systems. There are many efforts to reduce the consumption of organic solvents because of their toxicity to the environment and human health. In recent years, several groups have started to explore novel organic solvents called room temperature ionic liquids in order to substitute conventional organic solvents. In this work, lipase-catalyzed transesterification in several uni- and bi-phasic systems was studied. Two representative hydrophobic ionic liquids based on 1-butyl-3-methylimidazolum coupled with hexafluorophosphate ([BMIM][$PF_6$]) and bis[{trifluoromethylsulfonyl} imide] ([BMIM] [$Tf_{2}N$]) were employed as reaction media for the transesterification of n-butanol. The commercial lipase, Novozym 435, was used for the transesterification reaction with vinyl acetate as an acyl donor. The conversion yield was increased around $10\%$ in a water/[BMIM][$Tf_{2}N$] bi-phasic system compared with that in a water/hexane system. A higher distribution of substrates into the water phase is believed to enhance the conversion yield in a water/[BMIM][$Tf_{2}N$] system. Partition coefficients of the substrates in the water/[BMIM][$Tf_{2}N$] bi-phasic system were higher than three times that found in the water/hexane system, while n-butyl acetate showed a similar distribution in both systems. Thus, RTILs appear to be a promising substitute of organic solvents in some biotransformation systems.