• Korean Chemical Engineering Research
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• v.45 no.3
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• pp.304-309
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• 2007

In this study, the "Multi Well Plate-type cell Apparatus" was designed and setup for performing the producing experiments of methane hydrate by depressurization, heat stimulating methods. In order to characterizing the producing mechanism of hydrate through porous materials, the experiments for various producing methods have been conducted with the aid of the apparatus which has high permeability. In the experimental result of depressurization method, the pressure is temporarily increased unlikely conventional gas reservoir due to the sourcing effect of hydrate dissociation in the pore. Meanwhile, the temperature is decreased because of the endothermic reaction while hydrate is dissociated. In the experimental results of heat stimulating method, the dissociation in depressurization method is more slowly processed than that in thermal method, and hence, its gas production is lower. In the case of production right after heating, hydrate is dissociated only near injecting point and the permeability becomes greater at that area only. It infers that the more gas is produced during relatively earlier producing period. Since then, the hydrate is more slowly dissociated than the case of production after heating and soaking. This time, the performances of pressure and production obtained by thermal method have been analyzed in order to investigate the effect of soaking time on gas recovery. As a result, the gas recoveries in the case of 2 min and 4 min soaking are higher than case in 6 min soaking. This is reason that hydrate is reformed due to the decrease of temperature. It is expected that the experimental results obtained in this work may be more clearly explained by utilizing the lower permeable porous system with the greater hydrate saturation.

• Korean Chemical Engineering Research
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• v.45 no.3
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• pp.249-257
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• 2007

The periodic square wave (PSW) model was successfully applied to the optimal design of a batch-storage network. The network structure can cover any type of batch production, distribution and inventory system, including recycle streams. Here we extend the coverage of the PSW model to multitasking semi-continuous processes as well as pure continuous and batch processes. In previous solutions obtained using the PSW model, the feedstock composition and product yield were treated as known constants. This constraint is relaxed in the present work, which treats the feedstock composition and product yield as free variables to be optimized. This modification makes it possible to deal with the pooling problem commonly encountered in oil refinery processes. Despite the greater complexity that arises when the feedstock composition and product yield are free variables, the PSW model still gives analytic lot sizing equations. The ability of the proposed method to determine the optimal plant design is demonstrated through the example of a high density polyethylene (HDPE) plant. Based on the analytical optimality results, we propose a practical process optimality measure that can be used for any kind of process. This measure facilitates direct comparison of the performance of multiple processes, and hence is a useful tool for diagnosing the status of process systems. The result that the cost of a process is proportional to the square root of average flow rate is similar to the well-known six-tenths factor rule in plant design.

• Journal of Environmental Policy
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• v.9 no.1
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• pp.57-81
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• 2010

Since the Republic of Korea is highly dependent on fossil fuels despite high oil prices, it urgently needs to renew its economic and social system to cut carbon emissions and achieve green growth. Therefore, reforming or eliminating subsidies related to the use of fossil fuels is a timely and oppropriate policy recommendation for Korea. It would be a win-win deal for Korean society as it would not only reduce the use of environmentally harmful fossil fuels but also enhance economic efficiency. In particular, cross-subsidies for industrial, agricultural and night thermal-storage power services make up more than 80 percent of all subsidies provided to the entire electric power industry sector of Korea. Of these cross-subsidies, this paper analyzes the electricity subsidy for industries, which takes up the largest share (about KRW 1.6583 trillion yearly), among the environmentally harmful subsidies in the electric power sector. Thus, the paper focuses on the analysis of ripple effect anticipated when this is reformed. To examine the effects of this subsidy reform, price elasticities were estimated using the ARDL (autoregressive distributed lag) model and quarterly data from 1990 to 2007. The main results of this study show that 1) annual energy demand for electric power in the industrial sector would drop by 12,475,930MWh and 2) $CO_2$ emissions would plummet by 2,644,897 tons per year if the subsidy were reformed. We can deduct from this that the abolition of environmentally harmful subsidies in the electric power sector in the Republic of Korea would considerably contribute to $CO_2$ emissions abatement in the country.

• Journal of Environmental Policy
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• v.13 no.2
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• pp.99-129
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• 2014

This research estimates the impact of population aging on energy use and carbon emissions by energy sources and by industrial sectors in Korea until 2035. For the estimation, the structural change in household consumption expenditure identified by the age-specific consumption pattern was analyzed in conjunction with energy and environment input-output tables. The estimation result presents that, despite the population aging, energy use and carbon emissions induced by household consumption continue to increase until 2026, and then that elevated levels of energy use and carbon emissions will be maintained for a considerable period of time. According to the estimation by energy sources, the use of natural gas will show substantial increase while the use of crude oil will switch to a downturn at a relatively early period. According to the estimation by industrial sectors, carbon emissions in the sectors with relatively high consumption share of old households such as medical health, dwelling, lighting, heating, air-conditioning, and food will have substantial increase, whereas those in the sectors associated with education, transport, catering, and accommodation services will turn downward relatively early. In addition, the study analyzes through policy simulation the impact of aging-related policy similar to the basic pension system, which is recently being discussed for legislation, on energy use and carbon emissions.

• Journal of Environmental Health Sciences
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• v.36 no.5
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• pp.351-359
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• 2010

The objectives of this study were to understand the characteristics of residents in industrial areas and factors affecting exposure to the Volatile Organic Compounds(VOCs : Benzene, Toluene, Xylene) as well as to assess exposure levels according to house-type, and whether residents were indoors or outdoors. This research was designed to assess the differences in exposure levels to indoor, outdoor and personal VOCs in a case group and a control group across all areas, as well as in each different area, from May to October 2007, in. 110 residents of the G, Y and H industrial areas of the Jun-nam province. The geometric mea-levels of airborne benzene for the case group 1.31part per billion(ppb) indoor, 1.29 ppb outdoor, and 1.32 ppb for personal exposure were significantly higher than for the control group 0.99, 0.87 and 0.57 ppb, respectively. The geometric mean level for toluene personal exposure across the G, Y and H areas was 5.70 ppb for the case group and 6.31 ppb for the control group. While the outdoor level was 4.27 ppb for the case group and 5.06 ppb for the control group, The indoor level for the case group was 4.78 ppb, similar to that of the control group 4.69 ppb. The geometric mean levels for airborne xylene across the G, Y and H areas were 0.16 ppb(outdoor), 0.12 ppb(personal exposure) and 0.10 ppb(indoor) for the case group, and for the control group were 0.17(personal exposure) and 0.09 ppb(indoor and outdoor). The indoor/outdoor(I/O) ratio for case group is 1.19, while that of the control group is 1.15, indicating that the indoor level was higher than the outdoor level. The interrelationship differences among the three different types of levels in the air in the G, Y and H areas are statistically significant, except for the difference between the indoor and outdoor figures for xylene. In terms of the different types of houses and energy type uesd, the geometric mean level for airborne benzene, toluene and xylene for houses were 1.61, 5.39 and 0.12 ppb, respectively. while the figures for flats were 0.67, 3.32 and 0.05 ppb, respectively. Outdoors, the levels of benzene and toluene in flats were 0.71 and 2.62 ppb, respectively. and 1.58 and 5.35 ppb in houses. For personal exposure, the house levels of benzene, toluene and xylene were all higher than for flats. Houses using oil for heating have significantly higher levels than flats, which use gas for heating.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.4
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• pp.525-528
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• 2009

In this study, phytosterol content and fatty acid composition of grape seeds from fourteen different cultivars produced in Korea were determined. Although the total phytosterol contents depended upon the cultivars, the major phytosterol was $\beta$-sitosterol (64.9$\sim$119.3 mg/100 g) in all samples. The fatty acid composition of the grape seeds were analyzed as palmitic (16:0, 6.8$\sim$16.8%), palmitoleic (16:1, 0.1$\sim$0.2%), stearic (18:0, 4.7$\sim$5.2%), oleic (18:1, 16.6$\sim$26.1%), linoleic (18:2, 16.6$\sim$20.1%), linolenic acid (18:3, 0.3$\sim$0.5%) and arachidic acid (20:0, 0.3$\sim$0.5%). Campbell early, the mainly produced and consumed cultivar in Korea, contained relatively high phytosterol content compared to other samples and high proportion of unsaturated fatty acids. Therefore, the seeds from Campbell early might be used for functional oil production and as food ingredients.

• Journal of the Korean Home Economics Association
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• v.41 no.3
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• pp.181-196
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• 2003

Investigated kinds and utilization frequency for traditional food and Particular food to systematize Gwangju city and Chollanamdo area traditional food culture. Awareness for traditional food had pride because taste is various, and did that must use much when was festive day. Investigation subject were feeling necessity about accession, development of traditional food, and manufacture of traditional food, succession did that must take charge in home. Characteristic of taste for Gwangju city, Chollanamdo food was deep taste. Difference between variable was significant that age, religion that have pride about traditional food, attainments in scholarship, monthly income that used time much traditional food, degree that give from traditional food to snack is age, attainments in scholarship, years of married life, religion, reason that give snack to traditional food is daughter-in-law order, kind of traditional food that give to snack is age, monthly income mouth, opinion about accession and development of traditional food is age, religion, daughter-in-law order, reason that must inherit and develop traditional food is attainments in scholarship, time that eat much traditional food is attainments in scholarship, a person, medium that learn cuisine of traditional food is age, opportunity that is been interested to traditional food is age, attainments in scholarship, years of married life. By utilization rate of food-tasting food subdivisions of the season, used much by rice-cake soup, fermented rice punch, order of cake made from glutinous rice New Year's Day, by herbs, Gimgui, Ogokbap's order January Full Moon Day on the lunar calendar. By a cake made in the shape of a flower, azalea honeyed juice mixed with fruits as a punch order to Samjitnal, by beans panbroiling, dropwort raw order Buddha's Birthday, Tano Festival uses Charyunbyeong and used Tteoksudan in Yudu and used much by young chicken soup with ginseng and other fruits, watermelon order period of midsummer heat. Used songpyon and fermented rice punch in Full-moon Harvest Day, and Junggujeol used Chrysanthemum griddle cakes made in flower Pattern, and red-bean gruel taken on the winter solstice, and Nappyeongjeolsik was utilizing Goldongban. Pyebaek food utilization ratio was high the utilization rate by chestnut, jujube, chicken, wine order. The contributiveness food utilization rate was high the utilization rate by rice cake, dried croaker, fruit, oil-and-honey pastry order. The large table food utilization rate was high the utilization rate by fermented rice punch, fruit, steamed short-ribs order.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.6
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• pp.1207-1220
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• 2009

Through the study on the constitution-favored food by each constitution, we can draw below conclusions : The number of food that corresponds to that on more than 3 literatures showed over 40 for lesser yang person, greater yin person and lesser yin person, however, the number for greater yang person only appeared about 20, half of the number for the others. This is considered to have resulted from the not-enough studies on greater yang person for its rarity. When looking into the portion of the constitution-favored food for each constitution, the portion of cereals, bulbous plants and beans takes 27% (average 16.4% in the constitution-favored food)for greater yin person-favored food, the portion of vegetables and mushroom shares 29%(average 23.6% in the constitution-favored food) for lesser yin person, while the portion of fish, shellfish and other sea-food shows an average 25%, almost same figure for greater yang person, lesser yang person and lesser yin person, but its portion for greater yin person comes up the lowest figure at 16.2%. The portion of fruit shows relatively bigger figure in the constitution-favored food for lesser yang person and greater yin person, while smaller for greater yang person and lesser yin person. Meat, milk and milk products, eggs, oil and fats, condiments and flavors are not found in the greater yang person-favored food. When classifying the constitution-favored food by 4-Chi, the cold-natured food which favorers for lesser yang person shows a major portion, and when classifying it by 5 tastes, the sweety food becomes major, further, when classifying it by the benefited organ, the food benefiting to spleen and stomach, the lesser yin person favored food, appears prevalent. Above conclusion, based on approximately 300 kinds of food which are classified as constitutional food on literatures, suggests the necessity of a steady study and requires us to develop new constitutional food with the contemporary technology of food-processing and to determine the constitutional suitability on the newly introduced food which is increasing its numbers through importation due to frequent oversea trading.

• Journal of Life Science
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• v.15 no.4 s.71
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• pp.572-577
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• 2005

In this study, the effect of Epimedii Herba (EH) on the antioxidative enzymatic activity was investigated. EH (100mg/kg) was intraperitoneally administered into rats for 2 weeks. On the last day, carbon tetrachloride $(50\%\;CCl_4,\;3.3ml/kg,\;i.p.)$ dissolved in olive oil was injected before 12 hours. EH-pread-ministered and $CCl_4-treated$ (EC) group showed higher inhibitory effect in aminotransferase (AST, ALT) activity compared to $CCl_4-treated (CT)$ group. Superoxide dismutase (SOD) and Catalase in EC group were increased compared to those of CT group. The activity of glutathione peroxidase (GPx) was significantly higher than those of CT group compared to EC group. These results suggest that EH has a hepatoprotective effect through scavenging the free radicals induced by $CCl_4$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.882-886
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• 2003

Effect of kochujang (Korean red pepper soybean paste) on the reduction of body weight and lipid levels of adipose tissues and serum were investigated in the rats fed a high-fat diet. Male Sprague-Dawley rats were fed for four weeks with diets containing either a normal diet (ND, based on the AIN-76TM diet), high fat diet (HFD, supplemented with 20% corn oil in ND), CK diet (10% commercial kochujang in HFD), TK I diet (10% 0 day (non-) fermented traditional kochujang in HFD), TKII diet (10% 6-month fermented traditional kochujang in HFD), or RPP diet (3% red pepper powder in HFD). CK, TK I and TKII in the diet significantly reduced the body weight gain compared to the control (HFD), whereas red pepper powder had no such effect. TKII supplementation in the high-fat diet reduced epididymal and perirenal fat pad weight significantly (p<0.05). Liver total lipid was lower in TKII diet group than other kochujang and RPP diet groups. TKII and CK decreased the content of triglyceride in epididymal and perirenal fat pad that increased by high-fat diet. The cholesterol content of the perirenal fat pad was the lowest in the TKII diet group. TKII was also effective in lowering serum cholesterol level. These results indicated that properly ripened (fermented for 6-month) traditional kochujang exhibited more suppressive effects on body fat gain and lipid levels of adipose tissue and serum than RPP, commercial kochujang and the kochujang without fermentation.