• Nuclear Engineering and Technology
• /
• 제38권7호
• /
• pp.675-680
• /
• 2006

The neutron transmutation doping of silicon (NTD), as a method to produce a high quality semiconductor, utilizes the transmutation of a silicon element into phosphorus by neutron absorption in a silicon single crystal. In this paper, we present the design of a neutron screen for a 6' Si ingot irradiation in the NTD2 hole of HANARO. The goal of the design is to achieve an even flat axial distribution of the resistivity, or $Si^{30}(n,{\gamma})Si^{31}$ reaction rate, in the irradiated Si ingot. We used the MCNP4C code to simulate the neutron screen and to calculate the reaction rate distribution in the Si ingot. The fluctuations in the axial distribution were estimated to be within ${\pm}2.0%$ from the average for the final neutron screen design; thus, they satisfy the customers' requirement for uniform irradiation. On the other hand, we determined the optimal insertion depths of the Si ingots by varying the critical control rod position, which greatly affects the axial flux distribution.

• 한국식생활문화학회지
• /
• 제11권5호
• /
• pp.643-649
• /
• 1996

This study was performed to investigate the adequacy of dietary fat and protein intakes among female college students. Daily intakes of energy, fat, protein, major amino acids and other nutrients were measured in 52 female college students. Daily energy intake was 75.8% of the recommended intake. Fat and protein consist 19.2% and 16.7% of the total calorie, respectively. The average protein consumption per day was 105% of the recommended intake. Essential amino acids intakes were more than the recommended amounts which appears in the 6th edition of Recommended Dietary Allowances for Koreans. However, when the intake of each essential amino acid was compared to the recommended amino acid requirement pattern, these subjects did not meet the estimated requirements. There was a highly significant correlation between daily protein intake and lipid intake implying the major sources of protein in the diet were also major sources of fat. Daily intakes of dietary fiber, vitamin C, iron, and phosphorous were above the recommended levels of intake. However, blood hemoglobin concentration was marginal indicating dietary iron consumption is not a good marker for iron status. Also, calcium intake was only 63.5% of the recommended intake. Therefore, these results imply that main problems for these subjects are low energy consumption, low calcium intake, and the quality of protein. However, as opposed to the hypothesis, the main energy sources were not the food items high in saturated fats such as instant foods, which should be emphasized further.

• 한국식생활문화학회지
• /
• 제22권6호
• /
• pp.841-847
• /
• 2007

This study was conducted to investigate on bone density and nutrient intake of university students in Seoul area. Nutrient intake data were obtained by using the 24-hour recall method to evaluate the usual diet of the subjects. BQI(bone quality index) of the subjects was measured by an Quantitative Ultrasound (QUS). The results are summarized as follows: The average height, weight, BMI of the male and female student were 173.3 cm, 68.5 kg, 22.7; 161.4 cm, 54.2 kg, 20.8, respectively. The BQI and Z-score of the subjects were 99.50, -0.69 in male student group, and 82.6, -1.15 in female student group, respectively. Normal, osteopenia and osteoporosis percentage by bone status were 73.8%, 24.9%, 1.3% in male student group, and 39.8%, 57.6%, 2.6% in female student group, respectively. Energy intake of male and female group were 71.7%, 79.1% of EER(estimated energy requirement) respectively. Fiber, Ca, Vit $B_2$, niacin, folic acid, Vit C intake were less than RI(recommended intake) and protein, phosphorus intake were higher than RI in subjects. Nutrient intake were not significantly related with BQI in male and female groups generally.

• 한국농림기상학회지
• /
• 제19권4호
• /
• pp.252-269
• /
• 2017

본 시험은 품종별 개화가 가능한 기준온도와 저온($5.0^{\circ}C$) 누적시간 및 발아 후 변온에 따른 평균 개화소요일수를 구명하여 국내 주요 사과품종('후지', '쓰가루')들과 국내에서 육성한 품종('추광', '감홍', '홍안', '홍금', '홍로', '홍소', '화홍', '섬머드림', '선홍')들의 개화기를 예측하고자 군위지역에서 4년(2009-2012년)동안 조사하였다. 또한, 이들 자료를 이용하여 군위 지역 기온이 현재보다 $5.0^{\circ}C$ 상승되었을 때의 개화시기를 추정하였다. 저온($5.0^{\circ}C$) 누적시간(저온요구도)의 처리 범위는 0~1,671hr 정도였고, 저온 처리 후 개화를 위한 고온(고온요구도) 처리 범위는 $5.0{\sim}29.0^{\circ}C$ 정도였다. 발아 후 변온 처리구들은 항온구(대조구), $5.0{\sim}10.0^{\circ}C$ 상승구 및 하강구로 분류하였다. 결과를 살펴보면, 저온에서의 누적시간이 짧을수록 개화소요일수가 길어지는 경향이 있었으며, 0hr 처리구의 발아 후 개화까지의 소요된 일수는 1,335~1,503hr 처리구보다 2~4주 정도 길었다. 품종 별로는 모든 품종이 발아 후 기온이 $10.0^{\circ}C$ 미만일 때 개화를 하지 못하였고, 저온요구도가 낮은 품종일수록 개화에 필요한 고온요구도가 낮았다. 발아 후 기온을 $15.0^{\circ}C$로 조절된 처리구들의 개화소요일수는 $10.0^{\circ}C$ 처리구들보다 1~3주 정도 빨랐다. 발아 후 변온 처리에서는 발아 후 기온 상승 처리구들의 발아 후 개화까지 소요된 일수가 항온 처리구보다 짧았다. 이상의 결과를 종합해보면, 국내 주요 사과품종들의 개화 기준온도는 $10.0^{\circ}C$로 생각되었으며, 군위지역의 기온이 지금보다 $5.0^{\circ}C$ 정도 상승된다고 가정하면, 개화기는 1주 정도 지연될 것으로 예측되었다.

• 대한지역사회영양학회지
• /
• 제16권2호
• /
• pp.195-205
• /
• 2011

This study was conducted to investigate the time spent, activity coefficient and energy expenditure on 7 different types of activity. Total of 386 5th and 6th grade primary school boys and girls in Seoul participated in this study. The participants spent 8 hrs for rest, 4 hrs for out of school study, 3 hrs for leisure, 1 hr 45 mins. for hygiene, 1 hr for commute, and 15 mins. for house choir activity in the day of 6 class hours. The average activity coefficient of 1 day for boys and girls were 1.69 and 1.64, respectively. The TEEs were 2,382 kcal and 2,050 kcal for boys and girls, respectively. The energy cost for study related activity (in school and study activities) was 40% of the TEE, and for rest 20%, for commute 9%, and for hygiene 10% of the TEE. The energy cost for house choir was only about 2% of TEE. The 91.2% participant's EER was higher than the EER shown in the table of 2010 DRI for Koreans. When the participant's EER was compared with the energy allowance calculated by the method in 2000 RDA for Korean, 81.6% was in the range of ${\pm}5%$, and the correlation coefficients between the 2 values were 0.981 for boys and 0.978 for girls, which means high agreements.

• 한국산학기술학회논문지
• /
• 제11권4호
• /
• pp.1239-1247
• /
• 2010

본 연구에서는 소프트웨어 제품을 개발하여 테스팅을 거친 후 사용자에게 인도하는 시기를 결정하는 방출문제에 대하여 연구되었다. 인도시기에 관한 모형은 무한 고장수에 의존하는 비동질적인 포아송 과정을 적용하였다. 이러한 포아송 과정은 소프트웨어의 결함을 제거하거나 수정 작업 중에도 새로운 결함이 발생될 가능성을 반영하는 모형이다. 강도함수는 여러 수명 분포들을 적합시키는데 효율적인 특성을 가진 콤페르쯔, 파레토, 로그-로지스틱 패턴을 이용하였다. 따라서 소프트웨어 요구 신뢰도를 만족시키고 소프트웨어 개발 및 유지 총비용을 최소화 시키는 방출시간이 최적 소프트웨어 방출 정책이 된다. 본 논문의 수치적인 예에서는 고장 간격 시간 자료를 적용하고 모수추정 방법은 최우추정법과 추세분석을 통하여 자료의 효율성을 입증한 후 최적 방출시기를 추정하였다.

• 한국컴퓨터정보학회논문지
• /
• 제15권5호
• /
• pp.125-132
• /
• 2010

본 연구에서는 소프트웨어 제품을 개발하여 테스팅을 거친 후 사용자에게 인도하는 시기를 결정하는 방출문제에 대하여 연구 하였다. 방출문제의 분포는 소프트웨어의 결함을 제거하거나 수정 작업 중에도 새로운 결함이 발생될 가능성이 있는 무한고장수를 가진 비동질적인 포아송 과정에 기초하였다. 수명분포는 지수 족 분포와 비지수족 분포를 이용한 최적 방출시기에 관한 문제를 비교 제시하였다. 이러한 지수 및 비지수분포에 근거하여 소프트웨어 요구 신뢰도를 만족시키고 소프트웨어 개발 및 유지 총비용을 최소화 시키는 최적 소프트웨어 방출 정책에 대하여 논의 되었다. 본 논문의 수치적인 예에서는 고장 간격 시간 자료를 적용하고 모수추정 방법은 최우추정법을 이용하고 추세분석을 통하여 자료의 효율성을 입증한 후 최적 방출시기를 추정하였다.

• 동아시아식생활학회지
• /
• 제17권2호
• /
• pp.192-197
• /
• 2007

The purpose of this study was to evaluate the energy intake and energy expenditure of obese children. The body weight and height were measured, and the daily energy intake and activity pattern assessed for one day, using the 24 hour recall method and interviews in 83 elementary school children (59 boys and 24 girls). The average age, height, weight, ideal body weight and obesity index in boys and girls were 11.8 years, 144.8 cm, 54.2 kg, 39.9 kg and 35.9% and 11.5 years, 140.8 cm, 48.9 kg, 36.9 kg and 33.7%, respectively. The mean daily energy intakes of boys and girls were 1,670.5 and 1,656.5 kcal; these being 76.4 and 88.5% of estimated energy requirement for Koreans, respectively. The energy intake ratio from carbohydrates, proteins and fats in boys and girls were 61.5:14.7:23.6 and 62.0:14.7:23.7, respectively. The resting energy expenditure, as estimated by the Harris-Benedict, WHO/NAO/FAO and Korean DRI formulae in boys and girls were 1,452.7, 1,239.2 and 1,629.2 kcal and 1,323.9, 1,156.0 and 1,252.4 kcal, respectively. The activity coefficient for both the boys and girls was 1.39. The daily energy expenditure of boys (1,990.7 kcal) was significantly higher than that of girls (1712.1 kcal). No significant correlations were found between the obesity index, energy intake and energy expenditure. These results suggested that a nutrition and exercise program is required to increase the energy expenditure of elementary school children. Further research will be needed to assess multiple dietary factors and dove]lop a standard method for assessing the energy expenditure of obese children.

• 한국산학기술학회논문지
• /
• 제10권8호
• /
• pp.1903-1910
• /
• 2009

본 연구에서는 소프트웨어 제품을 개발하여 테스팅을 거친 후 사용자에게 인도하는 시기를 결정하는 방출문제에 대하여 연구하였다. 인도시기에 관한 모형은 무한 고장수에 의존하는 비동질적인 포아송 과정을 적용하였다. 이러한 포아송 과정은 소프트웨어의 결함을 제거하거나 수정 작업 중에도 새로운 결함이 발생될 가능성을 반영하는 모형이다. 고장발생 수명분포는 여러 분포들을 적합시키는데 효율적인 특성을 가진 와이블분포를 이용하였다. 따라서 소프트웨어 요구 신뢰도를 만족시키고 소프트웨어 개발 및 유지 총비용을 최소화시키는 방출시간이 최적 소프트웨어 방출 정책이 된다. 본 논문의 수치적인 예에서는 고장 간격 시간 자료를 적용하고 모수추정 방법은 최우추정법과 추세분석을 통하여 자료의 효율성을 입증한 후 최적 방출시기를 추정하였다.

• 대한지역사회영양학회지
• /
• 제27권1호
• /
• pp.47-60
• /
• 2022

Objectives: This study aimed to evaluate dietary protein intake and its adequacy among Korean adults during recent 10 years. Methods: Based on the 2010 ~ 2019 Korea National Health and Nutrition Examination Survey (KNHANES) data, a total of 51,296 adults aged 19 years old or more who participated in a one-day 24-hr dietary recall were included. Dietary protein intake was estimated as percentages of total energy (% of energy) and grams per body weight (g/kg/day) and compared with the 2020 Dietary Reference Intakes for Koreans to evaluate the adequacy of protein intake. In addition, proportions of people whose protein intakes were less than the estimated average requirement (EAR) and above the upper limit of the acceptable macronutrient distribution range (AMDR) (> 20% of energy) were calculated according to sociodemographic characteristics. Results: Protein intake was increased from 14.7% of energy in 2010 to 15.6% of energy in 2019 among Korean adults. However, there was no increase in protein intake relative to the recommended nutrient intake (% RNI) during the recent 10 years. Protein intake relative to the RNI was decreased from 130.2% in 2010 to 121.1% in 2019 (P for trend < 0.0001) among total participants, and a significant decreasing trend was observed in all age groups except for over 65 years old. However, protein intake relative to the RNI was lowest in the elderly (98.6%). Proportions of low protein intake (< EAR) and high protein intake (> AMDR) increased in the past 10 years (P for trend < 0.0001 for all), and these were associated with socioeconomic statuses, such as education and household income levels. Conclusions: These findings suggest that protein adequacy in Korean adults has not been improved over the past decade compared with recommended levels. Nutritional education and intervention programs should consider different intake levels according to sociodemographic characteristics.