• Journal of the Korean Institute of Gas
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• v.22 no.2
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• pp.21-28
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• 2018

In recent years, payability of shale gas production has worsened due to oil and gas price declines resulting from sharply increasing shale gas production. Reliable economic evaluation in shale gas development has become important. In this study, Monte Carlo simulation of probabilistic analysis technique was applied to analyze the economic feasibility considering the uncertainty involved in shale gas development. For this, the range of major variables is set and a random number is generated to derive the probability distribution of Net Present Value(NPV) and Internal Rate of Return(IRR). Consequently, we estimated the probability that the feasibility of the project is evaluated to be positive when developing shale gas in the study area. In addition, sensitivity analysis of major parameters affecting economic efficiency in shale gas development was carried out, and the effect of major variables in economic evaluation for commercial production was identified. In the future, this study could be used to make decision for shale gas production by presenting the range of variation of economic index and probability value.

• Journal of Korea Technology Innovation Society
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• v.17 no.1
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• pp.25-44
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• 2014

This study analyzed technological competitiveness of five major countries by using patent information that is typical intellectual property. Technological activity, patent competitiveness, market securement and patent concentration were designed as evaluation items for the technological competitiveness analysis, and the number of patent applications, family patents and triad patent families, and the paten concentration index were reflected as evaluation factors to be scored. For technologies to be analyzed, it referred to the energy harvesting technologies selected as 500 future technologies in the future technologic white paper 2013 published by KISTI. They were classified into technologies using thermoelectric, piezoelectric and photovoltaic elements, which are main detailed technologies of the energy harvesting technology, to investigate and analyze patent information for each detailed technology to understand their technological competitiveness. As a result, the United States ranked top with 75 and 70 points in the technology using thermoelectric and piezoelectric elements respectively, and Japan ranked top with 90 points in the energy harvesting technology using photovoltaic elements. It was analyzed that Korea held the second rank in the field using piezoelectric and photovoltaic elements, and the fifth in the technology using thermoelectric elements.

• Nutrition Research and Practice
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• v.9 no.4
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• pp.379-384
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• 2015

BACKGROUND/OBJECTIVE: Apolipoprotein A5 gene promoter region T-1131C polymorphism (APOA5 T-1131C) is known to be associated with elevated plasma TG levels, although little is known of the influence of the interaction between APOA5 T-1131C and lifestyle modification on TG levels. To investigate this matter, we studied APOA5 T-1131C and plasma TG levels of subjects participating in a three-month lifestyle modification program. SUBJECTS/METHODS: A three-month lifestyle modification program was conducted with 297 participants (Age: $57{\pm}8years$) in Izumo City, Japan, from 2001-2007. Changes in energy balance (the difference between energy intake and energy expenditure) and BMI were used to evaluate the participants' responses to the lifestyle modification. RESULTS: Even after adjusting for confounding factors, plasma TG levels were significantly different at baseline among three genotype subgroups: TT, $126{\pm}68mg/dl$; TC, $134{\pm}74mg/dl$; and CC, $172{\pm}101mg/dl$. Lifestyle modification resulted in significant reductions in plasma TG levels in the TT, TC, and CC genotype subgroups: $-21.9{\pm}61.0mg/dl$, $-20.9{\pm}51.0mg/dl$, and $-42.6{\pm}78.5mg/dl$, respectively, with no significant differences between them. In a stepwise regression analysis, age, APOA5 T-1131C, body mass index (BMI), homeostasis model assessment-insulin resistance (HOMA-IR), and the 18:1/18:0 ratio showed independent association with plasma TG levels at baseline. In a general linear model analysis, APOA5 T-1131C C-allele carriers showed significantly greater TG reduction with decreased energy balance than wild type carriers after adjustment for age, gender, and baseline plasma TG levels. CONCLUSIONS: The genetic effects of APOA5 T-1131C independently affected plasma TG levels. However, lifestyle modification was effective in significantly reducing plasma TG levels despite the APOA5 T-1131C genotype background.

• Journal of Radiation Protection and Research
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• v.25 no.4
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• pp.233-239
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• 2000

The sensitivity analysis of input parameters was Performed fer an ingestion dose assessment model (U. S. NRC's Regulatory Guide 1.109 model) from routine releases of radionuclides. In this study, three kinds of typical Korean foodstuffs (rice, leaff vegetables, milk) and two kinds of radionuclides $(^{l37}Cs,\;^{131}I)$ were considered. The values of input parameters were sampled using a Latin hypercube sampling technique based on Monte Carlo approach. Sensitivity indices, which represent the influence or the importance of input parameters for predictive results, were quantitatively expressed by the partial rank correlation coefficients. As the results, the ratio of the interception fraction to the yield of agricultural plants and the human consumption rate were sensitive input parameters for the considered foodstuffs and radionuclides. Additionally, in case of milk, the transfer factor of radionuclides from animal intake to milk and the daily intake rate of feedstuffs were sensitive input parameters. The weathering removal half-life and the delay time from food production to human consumption were relatively sensitive for $^{137}Cs$ and $^{131}I$ depositions, respectively.

• Journal of Nutrition and Health
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• v.35 no.5
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• pp.544-557
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• 2002

This study was performed to evaluate the quality of nutrient intakes of the hemodialysis patients (26 men and 23 women) according to the socioeconomic status by 3-day dietary recall in Daejeon city and Chungnam area, Korea. Mean age of the subjects was 50.7 yrs and BMI was 22.0 $\pm$ 0.4 kg/$m^2$. Education level was divided into two groups ($\leq$ 9 years： LE group, 9 years： HE group), and monthly family income level was divided into three groups (< 500,000 won: LI group, 500,000-1,499,999 won: MI group, $\geq$ 1,500,000 won : HI group). The data were analyzed by Student t-test and Oneway ANOVA using SPSS 9.0 version at p < 0.05 level. Intakes of energy, carbohydrates, cholesterol, potassium, thiamin and riboflavin were significantly higher in HE group than in LE group (p < 0.05). Intakes of all the nutrients except protein and phosphorus were less than Korean RDA, and INQs (Index of Nutritional Quality) of most nutrients were lower than 1.0 but cholesterol, phosphorus. thiamin and niacin being over 1.0 in HE group. MAR (Mean adequacy ratio) of all the nutrients (e.g., energy, protein, calcium, phosphorus, iron, vitamin A, vitamin C, thiamin, riboflavin and niacin) was significantly higher in HE group (0.61 $\pm$ 0.04) than in LE group (0.48 $\pm$ 0.03) at p = 0.036. Intakes of energy, protein (total, animal and plant), fat, cholesterol, potassium, calcium, phosphorus, iron, vitamin A, thiamin and riboflavin were also significantly higher in HI group than in LI and MI group (p < 0.05). Daily intakes of most nutrients were less than Korean RDA except protein ed phosphorus in HI poop, and INQs of thiamin, niacin and phosphorus were higher than 1.0, while those of calcium, iron, vitamin A and riboflavin were lower than 1.0. MAR of energy and 9 nutrients was significantly higher in HI group (0.70 $\pm$ 0.04) than in LI group (0. 56 0.04) and MI poop (0.47 $\pm$ 0.03) at p = 0.000. In conclusion, quality of nutrient intakes, especially energy and protein, was significantly influenced by socioeconomic status such as education and monthly income (p < 0.05). This result suggests that it would be very helpful to develop nutritional education programs considering hemodialysis patients' education levels, and to improve public supports (e.g., medical insurance system, low-rate lease system of dialysis equipments, etc.) focusing on the patients' family income levels f3r their better nutrition and health.

• Korean Journal of Community Nutrition
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• v.10 no.4
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• pp.501-512
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• 2005

To assess the food habits and the seasonal differences of nutrient intakes and diet qualities of adult working women aged 30 - 49y in Busan, dietary survey was conducted in summer and in winter by a questionnaire and two-day food record. Anthropometric assessment was also investigated in two seasons. $91.8\%$ of those skipped breakfast in the main. $44.3\%$ had irregular meals. The mean daily energy intake was 1725.8 kcal with $63.3\%$ of energy intake being supplied by carbohydrates, $14.7\%$ by protein, $22.3\%$ by fat in summer and 1598.4 kcal with $62.1\%$ of energy intake being supplied by carbohydrates, $15.6\%$ by protein, $22.1\%$ by fat in winter. Over $70\%$ of iron intake came from plant origin in two seasons. The mean intakes of energy, calcium, iron and vitamin A in summer and energy, calcium, iron, vitamin A and vitamin $B_2$ in winter were below Recommended Dietary Allowance (RDA) for Koreans. As well as insufficiency in iron, the bioavailability of iron is considered to have been low because most of iron intake came from plant origin in two seasons. For calcium and iron in summer and calcium, iron, vitamin A and vitamin $B_2$ in winter, proportions of subjects with intake levels less than $75\%$ of RDA were over $40\%$ in summer and over $50\%$ in winter, respectively. The nutrient adequacy ratios (NAR) were below 0.75 for calcium and iron in summer and calcium, iron, vitamin A and vitamin $B_2$ in winter. NARs of iron (p<0.05), vitamin A (p<0.01) and vitamin $B_2$ (p<0.001) in winter were significantly lower than those in summer. The mean adequacy ratios (MAR), an index of overall dietary quality were 0.85 in summer and 0.80 in winter. The MAR in winter was significantly lower than that in summer (p < 0.05). The indexes of nutritional quality (INQ) were below 1 for calcium and iron in summer and calcium, iron, vitamin A and vitamin $B_2$ in winter. The intake (p<0.05) and NAR (p<0.05) of vitamin $B_2$ showed positive significant correlations with height in winter. In conclusion, nutrient intake and diet quality of adult working women were different between the summer and the winter. So nutritional education programs for summer and winter are needed for adult working women.

• Journal of Nutrition and Health
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• v.41 no.6
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• pp.539-549
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• 2008

This study was conducted to examine food and nutrient intakes of weekday and weekend with 329 high school boys residing in Seoul using the 3-day food record. Frequency for breakfast skipping was the highest as compared with lunch and dinner skipping. Frequencies for breakfast and lunch skipping were significantly higher in weekend than weekday (p<0.05). The daily average food, vegetable food and animal food intakes were 1,327.6 g, 800.5 g, and 425.8 g, respectively. Total food and vegetable food intakes of weekday were significantly higher than weekend(p<0.05). The dietary variety score(DVS) was 20.5 in daily average, 23.3 in weekday and 15.1 in weekend, which showed significantly higher in weekday than weekend(p<0.05). The daily averages of energy, protein, fat and carbohydrate intake were 2244.9 kcal, 89 g, 72.6 g, and 311.2 g, respectively. Fat intake was significantly lower and carbohydrate, fiber, phosphate, iron, sodium, potassium, vitamin A, niacin, folate, and vitamin C intakes were significantly higher in weekday than weekend (p<0.05). The percentages of energy intake from carbohydrate, protein, and fat were 55.4%, 15.8%, 28.8% in daily average, 56.8%, 15.8%, 27.4% in weekday and 53.6%, 15.8%, 30.7% in weekend, respectively. The percentages of energy intake from carbohydrate in weekday and weekend were below 60%, and that from fat was above 27% in weekday and weekend. Carbohydrate intake was significantly higher and fat intake was significantly lower in weekday than weekend(p<0.05). Energy intakes of daily average, weekday and weekend were above 83% as compared with estimated energy requirement(EER). Intakes of dietary fiber, calcium, potassium, vitamin C, riboflavin and folate were below 75% as compared with adequate intake(AI) or recommended intake(RI). Mean adequacy ratios(MAR), an index of overall dietary quality were 0.78 in daily average, 0.80 in weekday and 0.75 in weekend. MAR of weekend showed significantly lower than weekday(p<0.05). This study revealed that the overall nutrient intake status was worse in weekend than weekday among high school boys.

• Journal of the Korean Society of Food Culture
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• v.34 no.6
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• pp.707-718
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• 2019

This study assessed the nutrient consumption of children from lunch at day care centers and kindergartens. A total of 184 lunch plates were selected in two child day care centers and two kindergartens in Seoul. Weights of the menus in planned meals were measured and amount of served and consumed lunches were calculated using a digital photography technique. Nutrients of the planned, served, and consumed lunches were assessed using CAN-Pro 4.0 and the Index of Nutritional Quality (INQ) was calculated for each meal. Compared with the estimated energy requirement for lunch for 3-5 year old children, the planned meals of the child day care centers and kindergartens contributed 42.8% and 98.8% of the daily energy requirements, respectively. At a child day care center, a served meal provided more nutrients than a planned meal since some children requested more servings after eating the served meals. This showed that the planned meal did not meet children's needs as well as the nutrient requirements. At the other child care center, children were served less than the planned meal by 6.8%, which resulted in serving less energy, calcium, potassium, and vitamin C than the required nutrients for lunch. Kindergarten A served meals with the energy requirement for lunch of 101.8%, but Kindergarten B served a meal with the energy requirement of 83.5%. Since the served portions were too small to meet nutrient requirements of the children, they consumed almost all the food served, and their nutrient consumption was similar to the nutrients served. Even though they consumed all the food served, their nutrient consumption did not meet their nutritional requirements. When assessed by INQ, the quality of the meal was good; children could consume enough nutrients when served proper quantity. Teachers who are responsible for serving meals need to be educated on proper portion sizes and how to encourage children to practice healthy eating. To promote healthy eating among children, parents need to provide children with messages consistent with what they have learned at institutions and to be a good role model in daily dietary life.

• Korean Chemical Engineering Research
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• v.57 no.6
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• pp.790-803
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• 2019

The dioctyl terephthalic acid (DOTP) process produces plastic plasticizers by esterification of terephthalic acid with powder in the form of octanol. In this study, the dust explosion characteristics of terephthalic acid directly injected into the manhole in the form of powder in the presence of flammable solvent or vapor in the reactor of this process were investigated. Dust particle size and particle size distribution dust characteristics were investigated, and pyrolysis characteristics of dust were investigated to estimate fire and explosion characteristics and ignition temperature. Also, the minimum ignition energy experiment was performed to evaluate the explosion sensitivity. As a result, the average particle size of terephthalic acid powder was $143.433{\mu}m$. From the thermal analysis carried out under these particle size and particle size distribution conditions, the ignition temperature of the dust was about $253^{\circ}C$. The lower explosive limit (LEL) of the terephthalic acid was determined to be $50g/m^3$. The minimum ignition energy (MIE) for explosion sensitivity is (10 < MIE < 300) mJ, and the estimated minimum ignition energy (Es) based on the ignition probability is 210 mJ. The maximum explosion pressure ($P_{max}$) and the maximum explosion pressure rise rate $({\frac{dP}{dt}})_{max}$ of terephthalic acid dust were 7.1 bar and 511 bar/s, respectively. The dust explosion index (Kst) was 139 mbar/s, corresponding to the dust explosion grade St 1.

• Journal of Soil and Groundwater Environment
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• v.26 no.3
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• pp.37-49
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• 2021

There is domestic Soil Contamination Warning Standard (SCWS) as remediation standard concentration of contaminated soils. No risk should be observed at soil concentration less than SCWS. Therefore, SCWS was evaluated to confirm the risk assessment. Background Concentration of Soil (BGC) and target remediation concentration were also assessed. The results show that Excess Cancer Risk (ECR) of SCWS was the highest in the groundwater intake pathway (Adult: 6.27E-04, Child: 2.81E-04). Total Cancer Risk (TCR) was 7.76E-04 and 4.30E-04 for adult and child, exceeding reference value (10^-6). Hazard Quotient (Non-Carcinogenic Risk, HQ) was the highest in the indoor air inhalation pathway (Adult: 3.64E+03, Child: 8.74E+02). Hazard Index (Total Non-Carcinogenic Risk, HI) exceeded reference value 1. ECR of the BGC was the highest in the groundwater intake pathway (Adult: 1.71E-04, Child: 7.67E-05). TCR was 2.12E-04 for adults and 1.17E-04 for children, exceeding the reference value (10^-6). HQ was the highest in groundwater intake pathway (Adult: 4.10E-01, Child: 1.84E-01). HI was lower than reference value 1 (Adult: 4.78E-01, Child: 2.50E-01). The heavy metal affecting ECR was Arsenic (As). The remediation-concentration of As was 7.14 mg/kg which is higher than BGC (6.83 mg/kg). TCR of As should be less than reference value (10^-6), but it was higher for all of SCWS, BGC and target remediation concentration. Therefore, it is suggested that risk assessment factors should be re-evaluated to fit domestic environmental settings and SCWS should be induced to satisfy the risk assessment.