• Journal of Nutrition and Health
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• 제23권7호
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• pp.504-512
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• 1990

In experiment 1, dietary self-selection of the 3 macronutrients, protein, fat, and carbohydrate were examined in male rats given 3 food cups of 80% carbohydrate, 80% protein, and 70% fat diets simultaneously. All the rats showed normal growth pattern and organ weight, which means they have ability to select just right kinds and amounts of nurients in order to support their growth and development. Mean values of caloric intake, body weight gain, serum lipid values and empty carcass compositions were not significantly differ between the upper and lower quartile groups of fat proportion of empty carcass compared to the lower quartile group(LF). Same feeding design was employed in experiment 2 where the effect of mild electric stress on food selection was studied. The rats in both control and electric stress group revealed a normal growth curve and organ weights. The rats in both control and electric stress group revealed a normal growth curve and organ weights. The stress group showed higher caloric intake and body weight gain than control group, but no significant effects of stress on serum and empty carcass components was found. Even though normal rats seemed to select macronutrients according to their physiolosical needs, there were individual differences in food selection whether they were exposed to stress or not. Therefore life long individual food selection pattern may have a great influence on nutritional status and chronic degenerative diseases of eldery, and on aging process.

• Asian-Australasian Journal of Animal Sciences
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• 제14권9호
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• pp.1245-1249
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• 2001

A study was conducted with 14 gayals to study their growth pattern from birth to 24 months of age, and gayal was compared with native calves and crossbred calves of gayals and exotic animals. A significant difference in liveweight gains up to 3 months (p<0.001) or up to 6 months (p<0.05) was found between gayal and native calves, but the difference reduced with increase of age and found non-significant (p>0.05) at 9 months and 12 months. The daily liveweight gain up to 3, 6, 9 or 12 months of age of gayals were 404.60, 306.80, 315.20 and 312.20 g/d, respectively and of native calves were 217.3, 245.3, 262.0 and 269.0 g/d, respectively. Gayal female calves had lower weights at birth (20.2 kg) and weaning (81.8 kg) and daily liveweight gains (298.5 g/d) than males (24.3 kg, 84.0 kg and 317.8 g/d, respectively) but the differences were not significant (p>0.05). Cross breeding gayal cows with Friesian bulls increased daily liveweight gain of the crossbred calves. The rate of increase of daily liveweight gain may further be increased if gayals are crossed with beef type animals, and optimum feeding may also be required which needs further research.

• 한국전자파학회논문지
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• 제14권4호
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• pp.363-368
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• 2003

본 논문에서는 고전력을 전송하기 위한 시스템에 사용되는 혼 안테나에 요구되는 특성을 연구하고 그에 따라 여러 혼 안테나의 특성을 비교, 분석하였으며, 최종적으로 다중 모드를 사용하는 원형 혼 안테나를 제안하였다. 고전력 전송 시스템에서는 전력 전송 효율이 매우 중요하며, 이를 위해 반사판 급전 혼 안테나로서 원형의 대칭 적인 방사패턴이 필요하며, 전력 누수와 간섭을 줄이기 위해 부엽이 억제되어야 한다. 뿐만 아니라 다중 모드를 사용함으로써, 혼 안테나의 전체적인 길이를 줄일 수 있고, 반사판 안테나의 형태, 방향에 따라 혼 안테나의 방사 패턴을 자유로이 조절할 수 있다. 또한 제작을 통해 이를 확인하였다.

• 한국전자파학회논문지
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• 제14권4호
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• pp.421-430
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• 2003

본 논문에서는 휴대폰 개발 초기단계에서부터 SAR(Specific Absorption Rate)를 고려할 수 있는 방법을 제안하였다. 먼저, 휴대폰의 폴딩 각도를 150$^{\circ}$에서 142$^{\circ}$까지 변화시키면서 SAR값을 계산하였다. 계산결과 폴더 각도가 작아질수록 SAR값이 감소함을 알 수 있었고, 142$^{\circ}$일 때 측정결과와 약 3.95 %의 오차가 있었다. EMI (Electromagnetic Interference) 방지 도료의 분포패턴을 변화시켜가면서 SAR값을 측정한 결과, 분포패턴이 다를 경우 SAR값이 다름을 알 수 있었다. 안테나 급전점 근처의 EMI 방지 도료를 제거할 경우 SAR 감소효율이 15.46 % 이었으며, 도료를 지그재그 패턴으로 분포시킬 경우 SAR 감소효율이 가장 크게 나타남을 알 수 있었다.

• 한국전자파학회논문지
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• 제11권4호
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• pp.619-626
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• 2000

본 논문에서는 $\infty$rrugation이 개구변에 수직인 환형 급전-혼 안테나의 전파반사를 FDTD 방법으로 해석하였 다. 동축선로로 혼 안테나가 급전할 때 thin wire 안테나 모델과 전계와 자계를 전압과 전류로 모댈렁한 1차원 F FDTD코딩방법을 이용하여 계산시간을 효율적으로 줄일 수 있었다. 중심주파수 11.8 GHz(X -band)에서 급천 동축선로의 특성임피던스를 50$\Omega$에서 20$\Omega$까지 lO$\Omega$씩 변화시켜 가며 계산한 결과 특성임피던스가 30$\Omega$인 경우 11 GHz-14 GHz의 넓은 주파수 영역에서 반사손실이 -25 dB 이상의 좋은 특성을 보인다. 또한 corrugation이 있을 때 방사패턴의 지향성이 개선되며 개구변에서의 위상오차가 감소됨을 확인하였다.

• 한국응용곤충학회지
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• 제30권3호
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• pp.174-179
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• 1991

1986~1990년에 3년근 인삼포장에서 참검정풍뎅이 유충에 의한 춘기 피해 양상을 조사한 결과 인삼포장의 바깥쪽일수록 피해가 심하였는데 이는 참검정풍뎅이 자성충의 dirks 이동 습성 때문으로 보인다. 3령 유충에 의한 3년근 인삼의 피해부는 뿌리 동례의 상부, 중부, 하부 또는 뿌리 전체였으며 드물게 지하부 줄게에도 피해가 있었다. 섭식기 3령층의 평균 서식 깊이는 인삼 유묘, 2년근, 3년근, 쑥에서 각각 3.2cn, 5.6cm, 6.6cm, 4.9cm 였다. 춘기의 참검정풍뎅이 유충에 의한 인삼의 피해는 주러 5월 중순에서 7월 상순에 발생하였고 강우량이 증가할 경우 피해가 일시적으로 감소하는 것으로 보였다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2015년도 제51회 KOSCO SYMPOSIUM 초록집
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• pp.93-96
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• 2015

Commercial coal gasifiers typically use entrained flow type reactors, but have unique features in terms of reactor shape, gasifying agent, coal feeding type, ash/slag discharge, and reaction stages. The MHI gasifier is characterized as air-blow dry-feed entrained reactor, which incorporates a short combustion stage at the bottom and a tall gasification stage above. This study investigates the flow and reaction characteristics inside a MHI gasifier by using computational fluid dynamics (CFD) in order to understand its design and operation features. For its pilot-scale system at 200 ton/day capacity, the distribution of coal and air supply between the two reaction stages was varied. It was found that the syngas composition and carbon conversion rate were not significantly influenced by the changes in the distribution of coal and air supply. However, the temperature, velocity and flow pattern changed sensitively to the changes in the distribution of coal and air supply. The results suggest that one key factor to determine the operational ranges of coal and air supply would be the temperature and flow pattern along the narrower wall between the two reaction stages.

• 대한가정학회지
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• 제11권3호
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• pp.329-344
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• 1973

The purpose of this study is to find how the mother's rearing patterns and attitudes influence on a child's social personality development. Many contemporary psychologists insist that mother's rearing attitudes and methods before age of six influence on child's social personality development a great deal. Freud divided the child's developmental stages into three : oral, anal, and phallic period. According to his assumptions the way of mother's feeding and weaning has very important relationship with the personality development through ora period and how to handle toilet training will greatly influence through anal period. In addition to this, Symonds declares that a mother's rearing attitudes will influence the establishment of social characteristics of the child. The moderate attitude-not too overprotective or rejective or submissive or dominate-is desirable. If mother's attitude declines to one aspect among these four kinds too much, the child would have chances to develop maladjusted social characteristics such as aggressiveness , submissiveness, dependency, and dominativeness. The hypotheses of this study were based on Freud and Symonds theory and tested by correlation and the difference of percentage. The results of the study were as follows : I. The relationship between rearing pattern and social characteristics 1. When the child has too strictly scheduled feeding time, he will have aggressive attitudes. 2. The longer the feeding period, the more dependency the child will have. 3. In case the toilet training was taken place too early or strictly, the child will withdraw into his shell. 4. When the child failed to perform the toilet training and was punished because of that, the child's personality will likely to be too submissive or aggressive. II. The relationship between mother's attitudes and social personality 1. When the mother's attitude is too overprotective the child showed withdrawn characteristics (r = 89) or dependency ( r = 24). 2. The child whose mother has too rejective attitude also showed withdrawn characteristics ( r = 31). As Sears insisted self-demanding schedule is recommendable and the weaning supposed to be started after age of one and a half years and finished around age of two. The toilet training which has rather severe consequences than the feeding methods should be started when the child is able to understand what is expected to him. Sears says that about two years after birth would be proper but individual difference should be considered. As a conclusion, Flexible and understanding attitudes and rearing methods is necessary for a sound establishment of social personality.

• 한국응용곤충학회지
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• 제32권3호
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• pp.354-371
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• 1993

컴퓨터와 자동감지장치를 이용하여 먹바퀴 성충 암컷의 행동을 사육상에서 10~15일간 연속 관찰하였다. 대체적으로 12L~12D의 광조건하에서 각 미소서식처에서의 출현율과 활동성에는 개체의 변이가 컸고 일주기성이 낮게 나타났다. 먹이, 물 타개체가 공급되었을 경우 휴식처, 타개체, 먹이 및 물이 있는 것에서 각각 하루 평균 20.42, 11.50, 6.31, 2.66% 출현했다. 먹이, 물 타개체를 공급하지 않았을 경우 휴식처에서 하루중 20.29% 출현하였다. 출현 시간당 방문 횟수는 다른 미소서식처에서보다 먹이 먹는 곳과 물 마시는 곳에서 많았고 먹바퀴의 활동성은 먹이, 물, 타개체를 공급했을 때가 공급하지 않았을 때 보다 높았다. 미소서식처 출현에 대한 Principal Component Analysis (PCA) 결과 각 개체들의 출현 양상은 다양하게 나타났으나 (Q모드), 각 시간대는 명, 암기로 유형화 되어 나타났다(R모드). 먹이, 물, 타개체 공급시 휴식처에서의 출현이 먹이를 먹는 곳과 물을 마시는 곳에서의 출현보다 명, 암기의 유형성이 강하게 나타났다. 각 미소서식처에서의 출현율과 활동을 종합적으로 고려하여 PCA한 결과 먹바퀴의 활동은 먹이 및 타개체가 있는 것의 출현율과 관련 되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권3호
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• pp.355-365
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• 2004

Two experiments were conducted to determine the effect of alkaline hydrogen peroxide (AHP) treatment (1% NaOH+1.5% $H_2O_2$; 1 AHPMS, 2% NaOH+1.5% $H_2O_2$; 2AHPMS) on rate and extent of degradation of mustard straw (MS) in sacco in sheep, and its in vivo digestion and ruminal fermentation characteristics when fed to sheep with concentrate (200 g per sheep daily). The treatment of straw with 1 and 2% AHP increased its sodium content by 148 and 296% to that of untreated straw (UMS). There was significant decrease in NDF and hemicellulose contents of AHP treated straw and increase in cellulose and lignin contents. Phenolic acids like ferrulic, $\rho$-coumaric and o-coumaric significantly (p<0.001) reduced by AHP treatment of mustard straw. In first experiment the in sacco degradation of DM, OM and NDF was significantly (p<0.01) greater for 2 AHPMS than for UMS at all incubation periods. The disappearance of nutrient from 1 AHPMS and 2 AHPMS treated straws continue to increase up to 96 h whereas in UMS the peak disappearance was found at 48 h. By using the equation {(y=a+b) ($1-e^{-ct}$)} the degradation rates (c) for DM, OM, and NDF were significantly higher for UMS than AHP treated straws. Level of alkali (1 and 2%) had significant effect on degradation characteristics (a, b, c and $P_{0.05}$) of DM and NDF fraction of MS. However, the effect was not pronounced on OM fraction of MS. In feeding experiment, the intake of nutrients for DM, OM, cell wall constituents and energy was higher on 2 AHPMS, whereas no effect on the digestibility of these nutrients was observed. The apparent nitrogen retention was higher (p<0.05) both in 1 and 2 AHPMS groups. Water intake by animals was significantly increased due to AHP treated mustard straw feeding. Rumen liquor pH was higher in 2 AHPMS fed animals. The $NH_3-N$ of rumen liquor was not affected by feeding of AHP treated MS based diets. Total VFA concentration was significantly (p<0.01) higher in UMS fed group. The fractional out flow rate of DM was higher (p<0.05) in animals fed on 2 AHPMS diets compared to UMS and lAHPMS fed groups. The population of large holotrichs was higher (p<0.05) on AHP treated MS fed diets compared to UMS. The study indicated that treatment of mustard straw with AHP changed its chemical composition towards a better feed. The nutritive value of 2% AHP treated mustard straw was better in terms of dry matter intake and apparent nitrogen retention. The higher in sacco DM, OM and NDF disappearance however, was not confirmed by in vivo data in this study.