• Nuclear Engineering and Technology
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• v.31 no.2
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• pp.139-150
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• 1999

The swelling pressure of a potential buffer material was measured and the effect of dry density, bentonite content and initial water content on the swelling pressure was investigated to provide the information for the selection of buffer material in a high-level waste repository. Swelling tests were carried out according to Box-Behnken's experimental design. Measured swelling pressures were in the wide range of 0.7 Kg/$\textrm{cm}^2$ to 190.2 Kg/$\textrm{cm}^2$ under given experimental conditions. Based upon the experimental data, a 3-factor polynomial swelling model was suggested to analyze the effect of dry density, bentonite content and initial water content on the swelling pressure The swelling pressure increased with an increase in the dry density and bentonite content, while it decreased with increasing the initial water content and, beyond about 12 wt.% of the initial water content, levelled off to nearly constant value.

• Journal of Nutrition and Health
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• v.33 no.8
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• pp.787-793
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• 2000

The purpose of the present study was to investigate effects of kochujang and red pepper on energy intake, body fat content and energy expenditure in rats fed on high-fat(30%) diet. Kochujang and red pepper power were added in the high-fat diet, adjusting the level to 95 and 22g/kg diet, respectively, The level of red pepper addition was corresponding was corresponding to the level of the content of red pepper powder in the kichujang-added diet. Kochujang induced a 30% reduction in body fat gain which was associated with a significant increase in energy expenditure. However, red pepper reduced body fat gain by only 15%. Furthermore, energy expenditure was not affected by red pepper. Metabolizable energy intake, apparent digestibility and body protein gain were not affected by either kochujang or red pepper. It has been known that capsaicin, a pungent component of red pepper, enhances activity of brown adipose tissue through increasing protein content. In the present study, in addition of protein content, DNA content of interscapular brown adipose tissue was also increased by kochujang. Therefore, it appeared that the anti-obesity effects of kochujang was greater than those of red pepper, indicating more than red pepper was involved in the expression of the anti-obesity effects of kochujang(Korean J Nutrition 33(8) : 787-793, 2000)

• Journal of the Korean Society of Food Culture
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• v.9 no.5
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• pp.447-455
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• 1995

The purpose of the present study is to assess nutrient content for providing nutrition information such as nutrition labeling on Korean dishes in restaurant and food service institutions. The content of nutrients was calculated in recipies used to prepare dishes which has been frequently consumed in such four groups as the literature, foodservice institutions of industries, restaurants, and households. The numbers of dishes surveyed were 15. Total numbers of literture used for recipies analysis are 20. Recipies used in foodservice institutions of industries were abstracted from the journal 'Guk-Min Young-Yang' published in Korea dietetic association and obtained with the help of dietitians working in those institutions. Also, recipies has been using in restaurants were given from the Korea restaurant association. Recipies in households was calculated from the secondary analysis of the Korean National Nutrition Survey. Nutrient content from foods except steamed rice and side dishes in each dish was calculated using data of Korean food composition table published. The content of energy and protein in 'Gal-bi tang' (beef-rib soup) were highest in recipes used at restaurants, vitamin C in recipes of food service institutions of industries due to the generous use of meats and vegetables than other recipies. 'Doen-jang chigae' (soybean paste stew) showed the lowest content of energy in results analyzing recipes presented on the literature and varied protein level by four groups for difference of protein source used. The content of energy in 'Gop-chang jeongol' (small intestines stew) is 150 kcal more than 'Soegogi jeongol' (beef stew) in general. The energy level of 'Daeji-galbi' jim (braised pork ribs) and 'Dak jim' (braised chicken) turned out to be the highest in recipies presented on literature. Variation of each nutrient content including energy and protein was relatively high, since some of foods used in 'Pibimbab' (mixed rice) varied with four groups. Amounts of energy and protein in 'Naeng-myeun' (cold noodles) is the highest in recipies of foodservice institution of industries because much amounts of noodle and meats were used comparing to other groups. The average content of energy in 'Pulgogi' (grilled meat with sauce) was 50% to Korea recommended amounts of one meal, 833.3 kcal. Content of vitamin $B_1$ in 'Jeuk pyeunuk' (boiled pork), which is made of pork meat, was higher than other dishes. The ingredients of frequently consumed Korean dishes were highly variable among the four groups which inevitably results in variation of nutrient content in each dishes. The high variation of nutrient content in each dish according to study requires careful collecting of the large number of recipies in presenting representative nutrient content for nutrition labeling on dishes in restaurant and food service institutions effectively.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2002.11a
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• pp.43-49
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• 2002

A7003 alloy has characteristics of their excellent weldability, high corrosion resistance and superior plastic working however the broadening of application for the alloy has been hampered by the lower extrudability associated by Mg content. For improvement of extrudability and enhanced recovery efficiency during Al scrap recyeling, it has been generally practiced to reduce Mg content in A7003 alloy. Therefore, it is necessary to investigate the influence of Mg content on mechanical strength and extrudability of A7003 alloy. For efficient material processing which has small amounts, life cycle assessment in material processing(MLCA) is evaluated. The quantitative analysis of energy requirements and $CO_2$ emission for production of A7003 extruded bar are estimated with different Mg content and billet pre-heating process (heating source by light oil or LPG). In particular, the estimation of energy requirements was performed within shipping and gating range (except the mining and extraction stages)to investigate the influence of the variables on energy requirements and $CO_2$ emission in detail. As Mg content increased, the flow stress and the extrusion pressure for A7003 alloy increased. It has been thought that an increment in extrusion pressure with increasing Mg content is caused by the solid solution hardening of Mg atoms in the matrix and increment in volume fraction of intermetallic compound, $Mg_2Si$. The extrudability and the tensile strength are equal to, or above that of conventional A 7003 alloy even the content of Mg varied from $1.1wt.\%\;to\;0.5wt.\%$ alloy. This means that minimizing the content of Mg in A7003 alloy can enhance recovery efficiency during Al scrap recycling. It can be quoted that rather than Mg content energy source for billet heating is a prime factor to determine the atmospheric $CO_2$ emission.

• Journal of Korean Society of Forest Science
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• v.95 no.5
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• pp.562-568
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• 2006

This study was conducted to examine the energy content and photosynthetic efficiency of Quercus mongolica stands in Korea. Study sites were located in Mt. Joongwang, Gangwon-do (1,000 m and 800 m above sea level), Mt. Baekwoon, Jeollanam-do (800 m a.s.l.), Mt. Halla, Jeju-do (1,000 m a.s.l.), Mt. Taehwa, Gyeonggi-do (350 m a.s.l.), and Mt. Wolak, Chungcheongbuk-do (300 m a.s.l.). Total energy content and annual energy accumulation in Q. mongolica stands were 2,916-6,435 GJ/ha and 284-441 GJ/ha, respectively. Lower latitude (N.L.) stands of Q. mongolica showed higher energy contents than higher latitude stands, but Quercus stands in Mt. Baekwoon had higher annual energy accumulation than those in Mt. Halla located at a lower latitude. During the growing season, the photosynthetic efficiency of 60 to 70-year-old Q. mongolica stands ranged from 1.19 to 1.34% while that of 35-year-old stands did from 1.87 to 1.95%. There were no significant differences in photosynthetic efficiency among the latitudes because solar radiation was higher in low latitudes.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.1155-1156
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• 2006

In this paper, we analyzed the effect of EVA Sheet Gel Content depending on curing condition for photovoltaic module. Gel Content was measured by manufacturing Glass/EVA Sheet/Back Sheet scheme at several curing temperature and curing time. And the surface analysis of EVA Sheet depending on process condition could be observed using SEM(Scanning Electron Microscope). Through this experiment, we could confirm that there are differences on Gel Content of EVA Sheet and surface configuration depending on curing temperature and curing time. To find out the optical characteristic dependency on curing condition, Class/EVA Sheet/Glass scheme was fabricated. The optical transmittance of EVA Sheet at visible wavelength was enhanced 5% when compared to Glass/Glass scheme. And the transmittance of $130^{\circ}C$/4min, $110^{\circ}C$/4min, $160^{\circ}C$/6min process condition was higher at ultraviolet wavelength range. These curing conditions could be regarded as the best process for suppression the discoloration speed of EVA Sheet under UV light.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.4
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• pp.465-473
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• 2011

To find the optimum mixing ratio of WGS catalyst with $CO_2$ absorbent for SEWGS process, water gas shift reaction tests were carried out in a fluidized bed reactor using commercial WGS catalyst and sand (as a substitute for $CO_2$ absorbent). WGS catalyst content, gas velocity, and steam/CO ratio were considered as experimental variables. CO conversion increased as the catalyst content increased during water gas shift reaction. Variations of the CO conversion with the catalyst content were small at low gas velocity. However, those variations increased at higher gas velocity. Within experimental range of this study, the optimum operating condition(steam/CO ratio=3, gas velocity = 0.03 m/s, catalyst content=10 wt.%) to get high CO conversion and $CO_2$ capture efficiency was confirmed. Moreover, long time water gas shift reaction tests up to 20 hours were carried out for two cases (catalyst content = 10 and 20 wt.%) and we could conclude that the WGS reactivity at those conditions was maintained up to 20 hours.

• Journal of Nutrition and Health
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• v.34 no.7
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• pp.809-820
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• 2001

The purpose of the study was to find out the rich sources of vitamin B-complexes in Korea. Thirty kinds of vitamin B-complex (thiamin, riboflavin, and niacin) rich foods were selected based on vitamin content in 100g edible portion, single serving size, 100kcal energy content, and 1999 national annual food supply data. The results were summarized as follows: \circled1 Most of the thiamin rich foods selected were fishes: half of the foods selected was fishes when based on the contents in single serving size. On the other hand, about half of the foods selected were vegetables when based on the thiamin contents in 100kcal energy content. A relatively large number of food groups were included such as fishes, vegetables, beans, grains, meats, etc. when based on the contents in 100g edible portion, and national food supply data. \circled2 Most of the riboflavin rich foods selected were fishes and shellfishes, and vegetables: half of the foods selected were fishes and shellfishes when based on the content in 100g edible portion; two-thirds of the foods selected were vegetables when based on the content in single serving size; half of the foods selected were vegetables when based on the content in 100kcal. \circled3 The most important niacin sources are fishes: Most than 60% of the foods selected were fishes when based o the 100g edible portion, single serving size, and 100kcal energy content. Laver is very important source of all 3 vitamin B-complexes in Korea when based on the content in 100g edible portion, 100kcal energy content, and national annual food supply but not in single serving size. On the other hand, rice is rice is sources of all 3 vitamin B-complexes when based on the national annual food supply, but not in single serving size. On the other hand, rice sources of all 3 vitamin B-complexes when based on the national annual food supply, but is not included in 30 rich foods selected based on the content in 100g edible portion, single serving size, and 100kcal energy content. Mushrooms are also very important food sources of thiamin, riboflavin, and niacin when based on the vitamin content in 100g edible portion, single serving size, and 100kcal energy content but not included in 10 rich food selected based on the national food supply data.

• Transactions of the Korean hydrogen and new energy society
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• v.30 no.6
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• pp.523-530
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• 2019

For the low-Pt electrodes for polymer electrolyte fuel cells (PEMFCs), the optimization of ionomer content for anode catalyst layers was carried out. A commercial catalyst of 20 wt.% Pt/C was used instead of 50 wt.% Pt/C which is commonly used for PEMFCs. The ionomer content varies from 0.6 to 1.2 based on ionomer to carbon ratio (I/C) and the catalyst layer is formed over the electrolyte by the ultrasonic spray process. Evaluation of the prepared MEA in the unit cell showed that the optimal ionomer content of the air electrode was 0.8 on the I/C basis, while the hydrogen electrode was optimal at the relatively high ionomer content of 1.0. In addition, a large difference in cell performance was observed when the ionomer content of the hydrogen electrode was changed. Increasing the ionomer content from 0.6 to 1.0 by I/C in a hydrogen electrode with 0.05 mg/㎠ platinum loading resulted in more than double cell performance improvements on a 0.6 V. Through the analysis of various electrochemical properties in the single cell, it was assumed that the change in ionomer content of the hydrogen electrode affects the water flow between the hydrogen and air electrodes bounded by the membrane in the cell, which affects the overall performance of the cell. A more specific study will be carried out to understand the water flow mechanism in the future, and this study will show that the optimization process of hydrogen electrode can also be a very important cell design variable for the low-Pt and high-performance MEA.

• Computers and Concrete
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• v.17 no.4
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• pp.553-566
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• 2016

Fracture energy is one of the key parameters reveal cracking resistance and fracture toughness of concrete. The main purpose of this study is to determine fracture behavior, mechanical properties and microstructural analysis of high strength basalt fiber reinforced concrete (HSFRC). For this purpose, three-point bending tests were performed on notched beams produced using HSFRCs with 12 mm and 24mm fiber length and 1, 2 and $3kg/m^3$ fiber content in order to determine the value of fracture energy. Fracture energies of the notched beam specimens were calculated by analyzing load versus crack mouth opining displacement curves by the help of RILEM proposal. The results show that the effects of basalt fiber content and fiber length on fracture energy are very significant. The splitting tensile and flexural strength of HSFRC increased with increasing fiber content whereas a slight drop in flexural strength was observed for the mixture with 24mm fiber length and $3kg/m^3$ fiber content. On the other hand, there was no significant effect of fiber addition on the compressive strength and modulus of elasticity of the mixtures. In addition, microstructural analysis of the three components; cement paste, aggregate and basalt fiber were performed based on the Scanning Electron Microscopy and Energy-Dispersive X-ray Spectroscopy examinations.