• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.19 no.4
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• pp.8-17
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• 2023

The air temperature is gradually increasing owing to global warming, especially in summer, therefore, the performance of an air source heat pump (ASHP) is expected to be decreased. Accordingly, the performance gap between the ASHP and ground source heat pump (GSHP) should be increased, however, the quantitative comparison has not been yet investigated. In this study, impact of global warming on the performance of the ASHP and GSHP is investigated based on the climate data for 1930, 1980, and 2030. The coefficient of performance (COP) as well as annual power consumption of the ASHP and GSHP are compared and analyzed. In the case of COP, the COP of GSHP hardly changes over the years owing to the constant ground temperature, while that of ASHP decreases by 3.7% for cooling and increases by 0.71% for heating. In the case of annual power consumption, the cooling and heating power consumption of GSHP increases by 12.69% and decreases by 15.58%, respectively, over the year owing to the changes in heating and cooling loads. As for the ASHP, the cooling and heating power consumption increases by 16.64% and decreases by 17.8%, respectively. For a more accurate comparison, power consumption ratio is introduced and shows that total annual power consumption of the GSHP to ASHP decreased from 68% in 1930 to 65% in 2030. Therefore, as global warming accelerates, the effect of reducing power consumption by using GSHP compared to ASHP is expected to be increasing.

• Nutrition Research and Practice
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• v.7 no.3
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• pp.185-191
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• 2013

In previous studies, we found that the consumption of legumes decreased bone turnover in ovariectomized rats. The purpose of the present study is to determine whether the protective effects on bone mineral density (BMD) and the microarchitecture of a diet containing legumes are comparable. In addition, we aim to determine their protective actions in bones by studying bone specific gene expression. Forty-two Sprague-Dawley rats are being divided into six groups during the 12 week study: 1) rats that underwent sham operations (Sham), 2) ovariectomized rats fed an AIN-93M diet (OVX), 3) ovariectomized rats fed an AIN-93M diet with soybeans (OVX-S), 4) ovariectomized rats fed an AIN-93M diet with mung beans (OVX-M), 5) ovariectomized rats fed an AIN-93M diet with cowpeas (OVX-C), and 6) ovariectomized rats fed an AIN-93M diet with azuki beans (OVX-A). Consumption of legumes significantly increased BMD of the spine and femur and bone volume of the femur compared to the OVX. Serum calcium and phosphate ratio, osteocalcin, expression of osteoprotegerin (OPG), and the receptor activator of nuclear factor ${\kappa}B$ ligand (RANKL) ratio increased significantly, while urinary excretion of calcium and deoxypyridinoline and expression of TNF-${\alpha}$ and IL-6 were significantly reduced in OVX rats fed legumes, compared to OVX rats that were not fed legumes. This study demonstrates that consumption of legumes has a beneficial effect on bone through modulation of OPG and RANKL expression in ovariectomized rats and that legume consumption can help compensate for an estrogen-deficiency by preventing bone loss induced by ovarian hormone deficiency.

• Journal of Nutrition and Health
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• v.39 no.7
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• pp.684-691
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• 2006

Abdominal obesity (AO) is a strong risk factor for type 2 diabetes and cardiovascular disease, which has shown a remarkable increase in Korea. This study aimed to identify prevalence of AO and related risk factors in Korean adults. A total of 5,132 men and women aged 20-85 years old from the 2001 Korean National Health and Nutrition Examination Survey were included in the analyses. AO was defined as waist circumference >=90 cm in men and >=85 cm in women as proposed by Korean Society of Obesity. Multiple logistic regression was carried out to identify risk factors for AO. Three models were specified: (i) demographic and socioeconomic factors (model 1: age, education, poverty income ratio, employment), (ii) lifestyle factors and covariates (model 2: physical activity, cigarette smoking, alcohol consumption, dietary quality, type 2 diabetes, co-morbidity) and (iii) demographic, socioeconomic and lifestyle factors (model 3). The prevalence of AO was 24.1 % in men, 23.5% in women. High poverty income ratio in men and low education attainment in women were risk factors for AO in model. 1. There was a significant association of AO with alcohol consumption, physical inactivity and dietary quality in men, alcohol consumption and cigarette smoking in women. These factors except alcohol consumption in men became insignificant in model 3. This findings underscore the importance of developing AO prevention programs in Korea that target the at risk groups identified in this study. A program focusing on low income men or less educated women would be more efficient.

• Journal of the Economic Geographical Society of Korea
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• v.16 no.2
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• pp.149-166
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• 2013

The purpose of this study is to analyze the regional disparity and its determinants of $CO_2$ emission from the residential energy consumption in China. This study examines factors that affect the $CO_2$ emission per capita using the panel model. The panel model was set by a balanced panel data for 30 provinces and for the period of 2006~2011. $CO_2$ emission per capita is used as the dependent variable and characteristics of the household and regional physical environmental factors are selected as the explanatory variables. The important findings can be summarized as follows. $CO_2$ emission per capita is influenced by the ratio of the graduate students, household size, the ratio of the old-aged, female economic participation rate. High residential density is negatively affected on $CO_2$ emission. The findings suggest that the effect of policies reducing $CO_2$ emission per capita may vary by characteristics of the household, energy sources and regional climate. The results of this empirical study give some implications to reduce the residential energy consumption in the era of climate change.

• Nutrition Research and Practice
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• v.8 no.1
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• pp.81-93
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• 2014

This study was conducted to investigate nutrient consumption by Korean adults in various places. To accomplish this, we used the 1998-2009 Korea National Health and Nutrition Examination Survey (KNHANES). Subjects of this investigation were over 19 years and the study included 37,160 people. The meals were categorized as breakfast, lunch, dinner, and snacks consumed at home, or while eating-out. Investigation of the rate of consumption at serving places based on daily meals and years showed that eating-out generally increased with time. The consumption of meals prepared at home was higher than that of meals consumed anyplace else in 1998, 2001, 2005, and 2007-2009. However, the rate of consumption of home meals decreased from 1998 to 2007-2009, while the rate of eating-out increased during this period. Annual nutrient intake according to serving places with respect to meals, energy, fat, and sodium were significantly lower in home meals than those consumed elsewhere in 2007-2009 relative to 1998. The sodium intake and energy distribution ratio of fat in meals consumed while eating-out increased significantly from 1998 to 2007-2009. The energy, fat and sodium intake and energy contribution ratio of fat consumed in meals at institutions was significantly higher in 2007-2009 than in 1998. Based on these results, additional research is required to develop guidelines for dietary life improvement at each serving place and to address education and policies for balanced nutrition intake.

• Journal of Nutrition and Health
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• v.39 no.6
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• pp.529-538
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• 2006

The prevalence of chronic diseases have been rising in the developing countries because of their increased animal foods consumption and Western lifestyle. Lately, vegetarian diet that exclude animal products get public attention. The purpose of this study was to evaluate the nutritional status and dietary quality of vegetarians, and their consumption of vitamin K and was also assessed. Vegetarians including strict vegan and lacto-ovo-vegetarian consumed their diet at least over 6 months. Carnivores were gender and age matched with vegetarians and they consumed over 50% of protein and fat from animal sources. Current nutrient intakes and dietary quality were assessed using 3-day food records and intake of vitamin K was calculated from the data base of 'Provisional Table on the vitamin K contents of foods, USA'. Blood sample were collected and biochemical parameters and plasma phylloquinone concentrations were analyzed. Anthropometric data from vegetarian and carnivore were not significantly different. The intake of calories, protein, vitamin $B_2$, Ca and Zn of the vegetarians were remarkably lower than RDA for each nutrient. Moreover, index of nutritional quality and nutrient adequacy ratio of vegetarians were lower than those of carnivore. Vegetarian consumed less fat and the ratio of n-6/n-3 fatty acid was lower in vegetarian. The intake of essential amino acids in vegetarian was significantly lower than that of carnivore. The vitamin K consumption and plasma phylloquinone concentration of vegetarian were significantly higher than those of carnivore (p<0.05). The dietary vitamin K consumption was positively correlated with plasma phylloquinone levels in vegetarian (p<0.01).

• Journal of the Korean Dietetic Association
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• v.12 no.4
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• pp.411-431
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• 2006

The purpose of this study was to assess the frequently consumed dish consumption frequencies of continuous ambulatory peritoneal dialysis(CAPD) patients with osteopenia and develop recipes to improve bone mineral density of CAPD. The subjects were 96 CAPD patients with osteopenia(male 39, female 57) (osteopenia group) and 45 CAPD patients with normal BMD(male 24, female 21), matched with key variables(normal group). Fifty dishes(foods) that most frequently consumed were determined and food consumption frequency for each dish(food) for two groups were compared. Osteopenia group showed lower consumption frequency for ice-cream but higher frequency in apple. Of the 50 most frequently consumed dishes(foods), 20 dishes assessed as safe and recommendable for CAPD patients with osteopenia based on the contents of protein and mineral were selected : white boiled rice, white gruel, beef soup, steamed cabbage, roasted dried laver, fried egg, roasted bean-curd, cooked and seasoned bean sprouts, corn-starch jelly, cheese, ice-cream, orange juice, apple, grape, peach, peanut, raw lettuce, raw cucumber, and injulmi rice cake. wenty eight new dishes with modified recipes were developed for CAPD patients. Protein and mineral contents were analyzed for frequently consumed 17 dishes, assessed as modification of recipes are needed. The recipes were modified to decrease P, Na and K contents and to increase protein and Ca contents. Twenty dishes(foods) selected as having reasonable protein and mineral contents ratio or 28 newly developed dishes modified with protein and mineral contents or ratio would be helpful for nutrition education or counseling for CAPD patients with osteopenia. Dishes(foods) suggested in this study would also be useful for all CAPD patients for preventing osteoporosis.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.4
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• pp.387-398
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• 2017

We attempted to develop a seafood menu by applying the most preferred recipes to the most disliked seafood menus in order to improve elementary schoolers' seafood menu preferences and consumption levels. A survey was conducted on the attitudes of 106 fifth graders about nine cooking methods and 37 school seafood menus served in the past 2 years. The deep-frying method was the most preferred by both boys and girls. The next preferred methods by boys were grilling and batter-frying while those by girls were stir-frying and batter-frying. The most disliked menus were cold jellyfish salad, mussel soup, dried-pollack soup, and sea-snail salad in that order. Mussel soup, dried-pollack soup, and seasnails salad ranked as the least preferred menu as well. Finally, standardized recipes for mussel croquette, dried-pollack Gangjeong, and batter-fried seasnails were developed. Consumption ratios of mussel croquette (85.94%), dried-pollack Gangjeong (79.55%), and batter-fried seasnails (75.5%) were significantly improved compared to the original menu (p<0.001). For mussel croquette, satisfaction scores for serving size, appearance, flavor, texture, and taste were significantly higher, and intakes of protein, phosphorus, iron, potassium, vitamin A, vitamin B1, vitamin B2, niacin, and vitamin C were significantly improved, as compared with mussel soup (p<0.001). Dried-pollack Gangjeong, texture and taste scores were significantly improved compared to dried-pollack soup. For batter-fried seasnails, protein, phosphorus, and iron intake levels and taste score were significantly improved compared to seasnail salad. Findings of the study suggest that a combination of disliked seafood ingredients and preferred recipes may be helpful in improving elementary school foodservice by increasing menu preference and consumption ratio.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.2
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• pp.212-215
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• 2016

In this paper, a 5.08 GHz Ring Voltage Controlled Oscillator(Ring VCO) was implemented using $0.18{\mu}m$ standard CMOS technology. The proposal Ring VCO is 3-stage structure. This research confirmed that the each stage's different transistor size ratio influence the current change and alter power consumption consequentially. This circuit is formed to control the current thereby adding the Current Mirror and to tune the frequency by supplying control voltage. It has an 65.5 %(1.88~5.45 GHz) tuning range. The measured output power is -0.30 dBm. The phase noise is -87.50 dBc/Hz @1 MHz offset with operating frequency of 5.08 GHz fundamental frequency. The total power consumption of Ring VCO is 31.2 mW with 2.4 V supply voltage.

• Journal of the Korean Home Economics Association
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• v.26 no.4
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• pp.43-52
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• 1988

This study is intended to reveal the nutritional realities of school children due to their box lunch. The samples were chosen at random from the third grade to the sixth grade children in an elementary school in Seoul : 122 male and 111 female children, 233 children in all. among the subjects, 44.3% have a family of four, 34.3% have over 500,000 won of family income a month, and 44.3% of their mothers graduated from a high school. The average intake of calories is 573.6 Kcal, and the ratios of the calory intakes to the recommended amounts are 90.6% in the third grade children and from the fourth grade to the sixth grade, 79.5% in the male children and 82.9% in the female children. The average consumption of protein is 21.0g and the ratio of animal protein is 41.4%. the ratio of energy yield nutrients is 67.4% : 14.5 : 18.0 (carbohydrate : protein " fat). Considering the recommended amounts, the intake of protein is enough; the consumption of vit, A, thiamine, niacin are appropriate;and the intake of calories, Riboflabin and ascorbic acid, calcium, iron are deficient. Even though there is no significant difference between the socioeconomic factors (the standard of education of the subjects' mothers and family income0 and the intakes of calories and protein, there is a tendency that the consumption of protein intake si more abundant in the middle class than in any other class. The subjects' distribution of the physical growth index, is as follows; A (6.9%), B(19.3%), C(48.5%), D(13.7%) and E (11.6%). As the subjects' intake of calcium increases, the weight shows significant improvement (p<0.001). As the consumption of calories increases, the physical development shows significant improvement (p<0.05), and the weight shows significant increase (p<0.001).