• 한국생산제조학회지
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• 제9권5호
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• pp.47-57
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• 2000

In this study, a fundamental approach to make clear the mechanism of the mutual interference and coalescence of stress fields in the vicinity of two crack tips on the process of their slow growth, using boundary element method. Automatic generation of quadratic discontinuous elements along both of the crack boundaries which can be defined by an arbitrary piece-wise straight geometry. The direction of the crack-extension increment is predicted by the maximum principal stress criterion, corrected to account for the discreteness of the crack extension. Along the computed direction, the crack is extended one increment. Automatic incremental crack-extension analysis with no remeshing, computation of the stress intensity factors by J-integral. Numerical stress intensity factors for two growing cracks in plane-homogeneous regions were determined.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2000년도 추계학술대회논문집
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• pp.65-68
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• 2000

Polyethylene, has long history and is widely used, was researched due to good electrical properties by many authors. But PE under stress has the critical defects of space charge accumulation and tree growth, so various methods such as catalyst, additives and blend to improve these problems have been execute, of which we selected blending method. As in our previous papers we investigated electrical conduction, dielectric and AC dielectric breakdown characteristics, we did DC dielectric breakdown characteristics in this paper. We selected pure LLDPE, pure EVA and LLDPE films mixed with EVA as specimens, which were mixed with the weight percentages of 50, 60, 70 and 80[wt%] to be thin film. DC applying voltage speed was 500[V/sec]. The relation between dielectric breakdown characteristics and the variations of super structure due to mixing was investigated, and especially trap level at amorphous region, threshold energy increment of conductive electron at free volume were considered.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.65-68
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• 2000

Polyethylene, has long history and is widely used, was researched due to good electrical properties by many authors. But PE under stress has the critical defects of space charge accumulation and tree growth, so various methods such as catalyst, additives and blend to improve these problems have been execute, of which we selected blending method. As in our previous papers we investigated electrical conduction, dielectric and AC dielectric breakdown characteristics, we did DC dielectric breakdown characteristics in this paper. We selected pure LLDPE, pure EVA and LLDPE films mixed with EVA as specimens, which were mixed with the weight percentages of 50, 60, 70 and 80[wt%] to be thin film. DC applying voltage speed was 500[V/sec]. The relation between dielectric breakdown characteristics and the variations of super structure due to mixing was investigated, and especially trap level at amorphous region, threshold energy increment of conductive electron at free volume were considered.

• 사상체질의학회지
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• 제22권3호
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• pp.122-131
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• 2010

1. Objectives: The purpose of this study is to find out the growth pattern according to Sasang Constitution. 2. Methods: One hundred forty seven students in the first grade of high school were classified into three groups(So-yangin, So-eumin, Tae-eumin) by QSCC II. We obtained the growth distance curve and growth rate, annual increment based on the Health Record according to Sasang Constitution. Health Record ranged from the first grade of the elementary school to the first grade of high school. And we calculated the Body mass index(BMI) and Mid-parential height(MPH). 3. Results: In case of Male, So-eumin and Tae-eumin showed linear growth patterns, but So-yangin showed rapid growth from 13 to 14. In case of Female, all of the groups showed similar growth pattern. But Tae-eumin showed a more growth from 8 to 9 than So-yangin groups. 4. Conclusions: Growth Pattern seemed to be different according to Sasang Constitution.

• Journal of Dairy Science and Biotechnology
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• 제28권1호
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• pp.9-16
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• 2010

Adolescents grow rapidly and have lots of schoolwork for entrance examination, so good nutrition is very important to them. However, adolescents tend to have a poor dietary behavior including frequent consumption of empty calorie foods and skipping breakfast. In particular, frequency of drinking milk has been low among Korean adolescents, thus their dietary calcium intakes has been low. Undesirable dietary behavior of adolescents is a risk factor for poor nutrition, obesity and chronic disease of them. Milk is a good source for calcium, high quality of protein, vitamin and bioactive compounds including anti-obesity component, thus it has been reported that milk helps improvement of dietary nutrient adequacy and physical growth, increment of bone mineral density, and prevention of obesity and chronic diseases. Therefore, milk consumption of adolescents should be encouraged in order to help their nutritional status, physical growth and health.

• 한국작물학회지
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• 제51권1호
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• pp.48-52
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• 2006

Naturally occurring soybean isoflavones are known to be influenced by various genetic and environmental conditions. Growth, yield, and isoflavone content were determined in four different cultivars of soybean grown under drained paddy and upland fields. Most of growth characteristics and yield components of four different soybean cultivars harvested in drained paddy field were greater than those in upland field, regardless of cultivar. By means of high performance liquid chromatography, total daidzein and genistein contents of soybean in drained paddy field were increased up to 40 and 35%, respectively, compared with those in drained paddy field. Besides isoflavone contents, the growth and yield of soybean were significantly affected by cultivar and field conditions, indicating the necessity of genetic program for soybean cultivars appropriate to drained paddy field conditions. In conclusion, converting paddy field into upland may effectively improve soybean cropping system, especially in terms of isoflavone increment under paddy field conditions.

• 대한치과교정학회지
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• 제15권1호
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• pp.123-140
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• 1985

Variation in the facial pattern and effect of the rotational jaw growth on the facial proportion were studied in serial cephalometric radiographs of 40 Korean children (25 boys, 15 girls) ranging in age from 6 to 13 years. According to Y-axis (N-S-Gn) growth change during the 7 years of period, the subject who had exhibited 'wave-like' manner of Y-axis growth change within ${\pm}\;2^{\circ}$ was classified to the Parallelwise group and the subject who had exhibited Y-axis increase more than $+2^{\circ}$ was classified to the Clockwise rotation group and the subject who had exhibited Y-axis decrease more than $-2^{\circ}$ was classified to the Counterclockwise rotation group. For the comparison of each group, a total of 22 morphologic variables were employed and the data were analyzed by means of computer morphometrics and statistical methods. On the basis of the finding of this study, the following trends were established. 1. The Parallelwise group was $75\%$, the Clockwise rotation group was $12.5\%$ and the Counter-clockwise rotation group was $12.5\%$. 2. The growth pattern of cranial base was related to the rotation of mandible. 9. Maxillary prognathism was occured in the Counterclockwise rotation group and the rotation of palatal plane was occured in the Clockwise rotation group. 4. Mandibular prognathism was occured in the Parallelwise and the Counterclockwise rotation groups, especially in the Counterclockwise rotation group. 5. The degree of maxillo-mandibular divergency was constant in the Clockwise rotation group but decreased in the Counterclockwise rotation and the Parallelwise groups, especially in the Counterclockwise group. 6. There were no differences in the size of the anterior upper facial height (N-ANS) and the posterior lower facial height ((Go-Me)-PNS) but there were differences in the size of the anterior lower facial height (ANS-Me) and the posterior upper facial height ((S-N)-PNS) between each group. 7. The growth increment and the size of the facial depth was not related to the growth pattern of the face but the growth increment and the size of the facial height was related to the growth pattern of the face. 8. Proportional change due to the facial growth rotation was concentrated in the anterior lower face. 9. The most apparent difference between each group was happened in the size of the posterior cranial base (S-Ba) and the facial length (S-Gn).

• 한국환경농학회지
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• 제19권5호
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• pp.394-400
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• 2000

${\gamma}-Radiation$ at very low doses frequently has a stimulating or hormetic effect on the growth of organism. Effects of low dose ${\gamma}-ray$ irradiation on the root growth of soybean cultivars were investigated and hormetic effects by environmental conditions were compared with the occurrence of increased economic yield, seeds of cultivars were irradiated with the dose of $0.5{\sim}20Gy$ and cultivated in growth chamber controling temperature, humidity, light, greenhouse and field respectively. To understand hormetic effect on root growth of cultivars and the difference of hormetic effect by cultivation environment, harvested root of soybean cultivars were scanned with image file, and root surface area, root length, root average diameter etc. were examined by WinRhizo program. Also, dry weight of cultivars was examined. Root growth and dry weight of soybean cultivars showed apparently hormetic effect at cultivation of growth chamber condition. In field experiment executed for whole life cycle, yields of pea were not different significantly in each ${\gamma}-ray$ irradiated cultivars but weight of one hundred peas increased in whole ${\gamma}-ray$ irradiated cultivars. Increment of yield was assumed to be induced through shortening of maturing stage caused by ${\gamma}-ray$ hormesis in early growth stage.

• 대한치과교정학회지
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• 제25권5호
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• pp.557-566
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• 1995

정상교합자의 사춘기 이후의 두개안면골 성장변화를 평가하기 위하여, 16세와 18세에 촬영한 연속 두부X선규격사진을 분석하였다. 대상은 남자 19명과 여자 14명이였으며 이들의 평균연령은 16.5세와 18.5세이였다. 관찰기간동안에 남자는 상,하악골, 두개저, 전,후방안면높이에서 통계적으로 유의한 증가가 있었으나(P<0.05), 여자에서는 하악골길이(Ar-Gn, Ar-Go) 그리고 전,후방안면높이에서만 유의한 증가가 있었다(P<0.05). 그러나 이 기간 동안 성장량은 여자에서는 전 계측항목에서 1mm이하 였으며, 남자에서는 전체 하악골길이 (Ar-Gn)는 2mm, 하악체길이 (Go-Me), 하악지길이(Ar-Go), 전,후방안면높이 (Na-Me, S-Go)는 $1mm\~1.54mm$였고, 나머지 항목은 1mm이하의 증가를 보였다. 또한 이 기간 동안에도 남자에서는 하악골평면각(SN/Mp)이 $-0.61^{\circ}$로 유의하게 감소하여 하악골의 전방으로 닫히는 변화가 있었다(p<0.01). 종합하면 본 연구기간동안에 여자는 비록 일부 항목에서 통계적으로 유의한 증가가 있었으나 그 양이 미미하여 임상적으로 그 변화를 인지할 수 없을 정도였으나 남자에서는 하악골과 관련된 부위에서 상당량의 증가가 인정되었다.

• 한국작물학회지
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• 제45권2호
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• pp.88-92
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• 2000

Excessive soil water in paddy field induces growth losses during the vegetative stages of soybean plants. Our objectives were to know growth responses of soybean as affected by the level of ridge heights. A field experiment was conducted at the Research Farm of Korea University near Seoul in 1996. Ten cultivars of soybean (Glycine max (L.) Merrill) were planted at the ridge heights of 10, 30, and 50cm in paddy soil on 27 June. Total dry matter accumulation at the 10cm ridge height was severely decreased until the growth stage of R5 as compared to the ridge heights of 30 and 50cm, and this decrement was mainly due to both reduced leaf and stem dry weights. However, seed dry weight was not significantly decreased at the lower ridge height with the increment of harvest index. Cultivar differences were found on seed dry weight, crop growth rate from R1 to R5, and leaf/stem ratio of R5. From the above results, soybean growth responses to excessive soil water in paddy field were different between seed filling stage and late vegetative to early reproductive growth stages.