• Earthquakes and Structures
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• v.23 no.3
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• pp.271-282
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• 2022

Seismic resisting self-centering bridge piers with high energy dissipation and negligible residual displacement after an earthquake event are focus topics of current structural engineering. The energy dissipation components of typical bridge piers are often relatively single; and exhibit a certain level of damage under earthquakes, leading to large residual displacements and low cumulative energy dissipation. In this paper, a novel socket self-centering bridge pier with a hybrid energy dissipation system is proposed. The seismic resilience of bridge piers can be improved through the rational design of annular grooves and rubber cushions. The seismic response was evaluated through the finite element method. The effects of rubber cushion thickness, annular groove depth, axial compression ratio, and lateral strength contribution ratio of rubber cushion on the seismic behavior of bridge piers are systematically studied. The results show that the annular groove depth has the greatest influence on the seismic performance of the bridge pier. Especially, the lateral strength contribution ratio of the rubber cushion mainly depends on the depth of the annular groove. The axial compression ratio has a significant effect on the ultimate bearing capacity. Finally, the seismic design method is proposed according to the influence of the above research parameters on the seismic performance of bridge piers, and the method is validated by an example. It is suggested that the range of lateral strength contribution ratio of rubber cushion is 0.028 ~ 0.053.

• Korean Journal of Community Nutrition
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• v.23 no.2
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• pp.93-101
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• 2018

Objectives: With the increasing number of single households and so-called Honbab-jok, those who eat alone, people tend to enjoy convenient and simple meals, such as single dish meals. This study was performed to provide data on the energy and nutrient content, and nutritional adequacy of single-dish meal. Methods: From the literature reviews, 61 types of single-dish meals were selected, and divided into 4 groups (steamed rice, noodle, porridge, and sandwich burger), and a further 11 sub-groups (bibimbab, fried rice, topped rice, rolled rice/ warm noodle, cold noodle, seasoned noodle, dukgook/ porridge/, and sandwich, burger). In addition, 382 junior high school students from Gyeonggi, Sejong, Jeonbuk, and Chungnam areas were recruited for the survey. The survey questionnaires were composed of the characteristics, preference, and intake frequency of single-dish meals. The representative energy content (arithmetic mean) of single-dish meals were calculated, and compared with the energy contents of preference and intake frequency-weighted values adjusted. The representative nutrient contents, energy contribution ratio, and INQ (index of nutritional quality) of a single-dish meal were calculated for a nutritional adequacy evaluation. Results: The study subjects considered a single-dish meal as tasty, simple and fast to prepare, inexpensive, nutritious, and no low calorie food. The preference scores of all but 1 sub-group of singledish meals were ${\geq}5.00$ (5.00~5.97), and 1 sub-group (porridge) was 4.67 on a 7-point scale. The intake frequency of 11 sub-groups were 0.31~1.71/week, porridge was the lowest at 0.31 and warm noodles was the highest at 1.71. Fried rice, rolled rice, and warm noodle' intake frequency were ${\geq}1/week$. The representative energy of steamed rice, noodle, sandwich burger were 443, 429, and 428 kcal, respectively, and that of porridge was 264 kcal. Less than 5% differences in the representative energy of 4 groups were observed when adjusted for the preference or intake frequency-weighted values. The energy contribution ratio of macro-nutrients calculations showed that porridge was a high carbohydrate and low fat food, whereas sandwich burger were high fat and low carbohydrate foods. The INQ of calcium and vitamin C were less than 1.0 in all 4 food groups, but the INQ of protein and thiamin were > 1.0 in all 4 single-dish food groups. Conclusions: The representative energy in the 4 groups of single-dish meal was 264~450 kcal, which is a rather low calorie meal, and the energy contribution ratio of macro-nutrients were inadequate. The protein and thiamin levels were sufficient but the calcium and vitamin C levels were insufficient in all 4 groups of a single-dish meal judged by the INQ. The additional intake of fruits and milk dairy products between meals with a single-dish meal, supply of calcium and vitamin C may increase, which will result in an improved nutritional balance.

• Journal of Korean Home Economics Education Association
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• v.19 no.4
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• pp.175-185
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• 2007

The purpose of this study was to analyze the nutritional adequacy of one-dish meals in the middle and high school technology & Home Economics textbooks cooking practice units. Total of 27 technology & Home Economics textbooks(9 books published by 9 different publishers each for grade 7, 9, and 10) were examined. The total number of one-dish meals introduced in the textbooks was 27, remarkably low, and there are only 7 Korean one-dish meals. It was found that most one-dish meals failed to meet 1/3 of daily estimated energy requirement. According to the analysis of energy contribution ratio by carbohydrate, protein, and fats in one-dish meals, only 4 Korean foods, such as Yubuchobab, Bibimbab, Deokguk and Guksujangguk showed ideal energy contribution ratio. Among the foreign foods, there was no one-dish meal with ideal energy contribution ratio. According to the index of nutritional quality(INQ) analysis, there was no such one-dish meal which supply all the essential nutrients in adequate amounts. All one-dish meals introduced in the textbooks contained excessive protein, but almost no vitamin $B_1$ and $B_2$. Ca and Fe, likely insufficient in Korean people, was found to be a nutrient insufficient also in most one-dish meals.

• Nuclear Engineering and Technology
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• v.54 no.7
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• pp.2572-2578
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• 2022

An approximate method for calculating the cadmium ratio of a cyclotron-based thermal neutron radiography system was developed. In this method, the Monte-Carlo code, MCNP6.2, was employed to calculate the neutron capture rates of Au-197, and the cadmium ratio was obtained by computing the ratio of neutron capture rates. From the simulation results, the computed cadmium ratio is reasonably acceptable, and the assumption of ignoring the fast neutron contribution to the cadmium ratio is valid.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.658-661
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• 2007

It was investigated on this paper that the status of biomass energy utilization in the registered CDM projects. The ratio of the case including the energy recovery among the registered biomass CDM projects is just about 57%. Direct thermal conversion technology is the most commonly applied for biomass energy recovery projects. Through the comparative study with world renewable energy outlook, the contribution of CDM to biomass energy supply in the world is not considerable yet.

• Korean Journal of Community Nutrition
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• v.20 no.2
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• pp.87-95
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• 2015

Objectives: Maintaining a balanced diet and thus health is crucial for adolescents, and the first step for balanced diet practice is meal planning. Adolescents, however, find it difficult to plan their meals. This study thus was set out to design an easier way of planning meals for adolescent girls. Methods: A dish-based target pattern for adolescent girls was tabulated, and validity of this was examined. Meal plan applying a dish-based target pattern was prepared by 150 female middle school students, and nutritional adequacies of those meal plans were examined. Validity and adequacy were tested by energy content, energy contribution ratio, nutrient adequacy ratio (NAR), probability of nutrient inadequacy, index of nutritional quality (INQ) calculation. Results: A dish-based target pattern with 11 dish groups was validated for nutritional adequacy. Though the NAR of calcium was 0.96, the INQ of calcium was 1.00. The average energy supply from the meal plans was 2,379 kcal, higher than the estimated energy requirement of a female middle school student, but the energy contribution ratio of carbohydrates, proteins, and fats were all adequate according to the acceptable macronutrient distribution range (AMDR). NAR of all nutrients examined were 1.0, except for calcium. The NAR and INQ of calcium were 0.87 and 0.75, respectively, and the meal plans at risk for calcium inadequacy was 19.30%. Conclusions: A dish-based target pattern proposed for adolescent girls was valid, but the meal plan prepared by female middle school students using this approach was high in energy and low in calcium supply. To cut down the energy supply from the meal plan, it is necessary to recommend dishes low in fat and use low fat cooking methods. To increase the calcium supply, it is important to recommend seaweed and legume group dishes with higher Ca INQ food items.

• Journal of the Korean Solar Energy Society
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• v.31 no.1
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• pp.100-106
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• 2011

This study proposes a $CO_2$ emission reduction method through correlation analysis of a sample building. First, energy saving factors of heating, cooling, lighting were determined for the correlation analysis and $CO_2$ emission contribution rate of the design parameters have been analyzed. Then optimal combination of each design parameter has been drawn. Heat transfer coefficient of walls and windows, air permeability, windows area ratio, and shading devices were selected as applicable energy saving factors of the sample building. Also computer simulation was conducted using experimental design by Orthogonal Arrays of the statistical method. And the contribution rate was estimated by Analysis of Variance-ANOVA. As a result, the $CO_2$ emission in heating was reduced to 51.9%; in cooling to 16.8%; and in lighting to 2% compared to the existing building. The majority of the reduction was presented by heating energy.

• Korean Journal of Community Nutrition
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• v.22 no.4
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• pp.279-288
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• 2017

Objectives: Recommended Menu (RM) prepared according to the Target Pattern expected to meet the dietary reference intake (DRI) of nutrients. Nutritional adequacy of RM in 'DRI for Koreans 2015' were analyzed to verify whether such expectation was fulfilled. Methods: Dishes in RM are categorized by 5 food groups, and number and types of dishes for main meal and between-meals were analyzed. The energy and 12 nutrients (protein, dietary fiber, Ca, P, Fe, Na, K, vitamin A, thiamin, riboflavin, niacin and vitamin C) contents in 10 RMs were calculated using the food composition table (CD) in 'DRI for Koreans'. Energy, energy contribution ratio, and nutrient contents in 10 RMs for 18 age groups were evaluated based on the 'DRI for Koreans 2015'. Results: Number of dishes per meal were 4.83, and representative table setting consisted of cooked rice + soup (or stew) +3 side dishes. Energy contents of RM were 75~109% of estimated energy requirement (EER). None of the RM met the DRI of all 12 nutrients examined. Calcium was the most insufficient nutrient. Only 1-2 years' RM met the DRI, all the other RMs did not meet the calcium DRI. Dietary fiber and potassium contents were also insufficient in most RM. In adult male's RM, only 1 nutrient, i.e. calcium did not meet the DRI, but in female adult's RM, 5~6 nutrients did not meet the DRI. Energy contribution ratio of carbohydrate, protein, and fat in RM were 59.0~70.4%, 15.7~17.5%, 12.1~23.5%, respectively. And 4 RMs out of 10 exceeded the upper limit of acceptable macro-nutrient distribution range (AMDR) of carbohydrate and 3 RMs out of 10 RM were below the lower limit of fat AMDR. Contribution ratio of nutrients were ${\geq}40%$ by food groups were as follows: grain group in energy and carbohydrate; meat fish egg legume group in fat, protein, and niacin; vegetables group in dietary fiber, vitamin A, and vitamin C; milk dairy products group in calcium. Conclusions: RM prepared according to the Target Pattern did not meet nutritional adequacy as expected. Especially calcium, potassium, and dietary fiber contents are needed to be increased in many RMs. Further, energy content in RM needs to be adjusted for fat sugar food group assigned in Target Pattern and condiment.

• Journal of the Korean Solar Energy Society
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• v.22 no.1
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• pp.1-8
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• 2002

With the possibility of hot water being able to be used as a heating source in a liquid desiccant system, an experimental apparatus for regeneration of the liquid desiccant was set up and series of experiments were conducted in a climate-controlled chamber. This study was performed to ascertain the influences of experimental factors on regenerating performance and to suggest the optimal combination of factors affecting regeneration rate. Furthermore. in order to figure out the contribution ratio of the factors on regenerating performance, a multi-way factorial design among the design of experiments was adopted. According to experimental results, the most influential factor on regenerating performance was temperature of the liquid desiccant and its contribution ratio was about 79.4%. In addition. the optimal operating combination was as follows; $60^{\circ}C$ of solution temperature, $14\ell$/min of solution flow rate, and 190m3/h of air volume.

• Korean Journal of Community Nutrition
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• v.20 no.1
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• pp.21-29
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• 2015

Objectives: Maintaining a balanced diet is very crucial for adolescents. However, adolescents, who may have a short notion about the amount of food, find it difficult to plan daily meals by applying the target pattern proposed by the Korean Nutrition Society. This study was carried out to revise the target pattern based on cooked dishes instead of raw material food groups as an easier way for Korean adolescents to plan their meals. Methods: Target pattern for Korean adolescents were revised based on the following: $1^{st}$, categorize dish groups, $2^{nd}$, calculate representative values of each dish based on the adolescent' intake amount. $3^{rd}$, assign the recommended number of intake for each dish. Validity of the target pattern for Korean adolescent meal plan was examined by the energy content, energy contribution ratio, and NAR & INQ of nutrients. Results: The 11 dish groups categorized were bab; gook tang gigae; side dishes of meat, fish, egg, legume, kimchi, vegetable, seaweed; and between meal of fruit, and milk dairy product. Based on the representative energy values, recommended number of intake were assigned to each dish. For boys, bab and gook tang gigae: 3 each; meat, fish, egg, and legume: 1 each; kimchi and vegetable: 3 each; seaweed: 1; fruit and milk dairy product: 2 each were assigned. For girls, bab and gook tang gigae: 2 each; meat, fish, egg, and legume: choice of 3 dishes, 1 each; kimchi and vegetable: 3 each; seaweed: 1; fruit and milk dairy product: 2 each were assigned. Energy contents, energy contribution ratio of carbohydrate, protein, and fat for boys and girls were in adequate range. The NARs were 1.0 and INQs were ${\geq}1.0$ for all nutrients examined. Conclusions: Revised dish-based, instead of food-based adolescent target patterns for boys and girls were easier and a valid way of Korean adolescent meal planning.