• The KSFM Journal of Fluid Machinery
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• v.13 no.6
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• pp.57-62
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• 2010

MW-class gas turbines are suitable for distributed generation systems such as community energy systems(CES). Recently, biogas is acknowledged as an alternative energy source, and its use in gas turbines is expected to increase. Steam injection is an effective way to improve performance of gas turbines. This study intended to examine the influence of injecting steam and using biogas as the fuel on the operation and performance a gas turbine combined heat and power (CHP) system. A commercial gas turbine of 6 MW class was used for this study. The primary concern of this study is a comparative analysis of system performance in a wide biogas composition range. In addition, the effect of steam temperature and injected steam rate on gas turbine and CHP performance was investigated.

• Journal of Hydrogen and New Energy
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• v.28 no.5
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• pp.440-446
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• 2017

This study was aimed at evaluating the effects of carbohydrate, protein and lipid content of substrate on hydrogen yields and microbial communities. The hydrogen yields were linearly correlated to carbohydrate content of substrates while others (content of proteins and lipids) did not make a significant contribution. The chemical composition of substrates produced effects on the final products of anaerobic hydrogen fermentation. Acetate and butyrate were the main fermentation products, with their concentration proving to correlate with carbohydrate and protein content of substrates. The result of microbial community analysis revealed that the relative abundances of Clostridium butyricum increased and Clostridium perfringens decreased as the carbohydrate content increased.

• International Journal of Human Ecology
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• v.12 no.2
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• pp.109-117
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• 2011

This study examines the infant crying acoustic characteristics likely to arouse negative emotions and distress in mothers. We used samples of infant crying from three situations (hunger, pain, and the mother's absence) in six healthy infants over six months. We played the recordings of infants crying to 90 mothers in the care of infants and had them self-evaluate emotions and feelings. In addition, the sounds were analyzed acoustically through a CSL4400 to analyze frequency, energy, total expiratory time, and the number of the expirations. In this study, cries due to pain and the absence of the mother caused more unpleasant emotions and irritation in comparison to the infant sounds of hunger. In particular, crying from the absence of the mother caused the most distress. An analysis of these sounds showed that crying in the situations of pain and the absence of the mother were strong in frequency, high energy, and prolonged. These results suggest a relation between infant crying acoustical characteristics and the feelings of distress by the mother.

• Korean Journal of Organic Agriculture
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• v.12 no.4
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• pp.359-375
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• 2004

Recently, many researches on the biomass of the agricultural and livestock wastes are being conducted in several respects. The use of biomass is of benefit to the curtailment of oil import, environmental pollution decrease, global warming mitigation and so on. And, in the agricultural sphere, making use of agricultural byproducts can contribute to the revitalization of the agricultural industry and rural community. In other words, making new products or energy by using biomass have a possibility to be developed as a new industry. The industry can create new businesses and job opportunities for rural dwellers. Also, major 3 positive effects of market formation for the agricultural wastes, increase of the idle land use and creation of the new business are expected. However, the use of biomass may be difficult to secure a proper right as a market good in the autonomic market economy. It is necessary to establish or amend related laws or systematic tools for the revitalization of the biomass use. Also, it is required for the government to bear partial costs of the facilities and others in the beginning stage.

• Journal of Energy Engineering
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• v.26 no.2
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• pp.99-120
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• 2017

In SS branch of Korea District Heating Corporation, Combined Heat & Power power plant with 99MW capacity and 98Gcal / h capacity is operated as a district electricity business. In this region, it is difficult to operate the generator due to the problem of surplus heat treatment between June and September due to the economic recession and the decrease in demand, so it is urgent to develop an economical energy new business model. In this study, we will develop an optimized operation model by introducing a renewable energy hybrid system based on actual operation data of this site. In particular, among renewable energy sources, fuel cell (Fuel Cell) power generation which can generate heat and electricity at the same time with limited location constraints, photovoltaic power generation which is representative renewable energy, ESS (Energy Storage System). HOMER (Hybrid Optimization of Multiple Energy Resources) program was used to select the optimal model. As a result of the economic analysis, 99MW CHP combined cycle power generation is the most economical in terms of net present cost (NPC), but 99MW CHP in terms of carbon emission trading and renewable energy certificate And 5MW fuel cells, and 521kW of solar power to supply electricity and heat than the supply of electricity and heat by 99MW CHP cogeneration power, it was shown that it is economically up to 247.5 billion won. we confirmed the results of the improvement of the zone electricity business condition by introducing the fuel cell and the renewable energy hybrid system as the optimization process model.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.1
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• pp.35-44
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• 2018

Korea government aims to generate 20 percent of its electricity with clean, renewable energy by 2030, while reducing its reliance on fossil fuel and nuclear power plants. Technically, solar energy has resource potential that far exceeds the entire global energy demand. Solar energy industry has experienced phenomenal growth in recent years due to both technological improvements resulting in cost reductions and government policies for renewable energy development and utilization. Even though solar power generation has several advantages over other forms of electricity generation, the major problem is the requirement of land which is scarcely available in the local site and its cost. This study analyzes the available capacity of landing and floating solar plants for the case of chonnam province in korea. The results of design capacity show about 7.5GW for landing and 1.5GW for floating solar power plant. Also, with a purpose to comprehend intention-behaviour gap about acceptance of solar community, the solutions are suggested.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.34 no.4
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• pp.49-56
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• 2011

The Project of Jordan Research and Training Reactor (JRTR) officially launched in Aug. 2010. JRTR is the first made-in-Korea nuclear system to be built abroad by year 2015, and Korea Atomic Energy Research Institute (KAERI) is responsible for the design of major systems including the reactor core. While the PDCS (Project Document Control System) being operated by EPC company controls all the documents of the whole Project, KAERI is supposed to have its own system for KAERI documents. Meeting such a need; KAERI has implemented a document control for the JRTR Project into already existing ANSIM (KAERI Advanced Nuclear Safety Information Management) system. The documents of JRTR project to be controlled are defined in the PPM (Project Procedures Manual), QAP (Quality Assurance Procedure) and PEP (Project Execution Program). The ANSIM consists of the document management holder, document container holder and organization management holder. The document management holder, which is the most important part of ANSIM-JRTR, consists of the DDA (Document Distribution for Agreement), IOC (Inter-office Correspondence), PM Memo. (Project Manager Memorandum) and cover sheets of design documents. Other materials such as meeting minutes, sub-department materials and design information materials are stored in an independent COP (Community of Practice). This established computerized document control system, ANSIM, could lessen a burden for project management team and enhance the productivity as well.

• Journal of Community Nutrition
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• v.1 no.1
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• pp.52-59
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• 1999

The present study was conducted to evaluate the dietary fiber intake of 130 subjects, that included 49 subjects(29 form Wonju, 20 from Kangnung) with diabetes mellitus, 23 hyperlipidemia patients, and 58 normal subjects. After the type and amount of foods that a subject took for one day were investigated using the 24-h recall method, the intake of various nutrients and dietary fiber were calculated using a program that already contained the information on dietary fiber contents. The results showed that diabetics from Kangnung who did not undergo dietary therapy had more fat intake that those from Wonju, hyperlipidemia patients, and normal subjects thus, had more energy intake. Also, the crude fiber intake in male and female diabetics from Kangnung were 8.43${\pm}$3.47g and 3.35${\pm}$3.29g, respectively, showing significantly high amounts compared to those of male and female diabetics from Wonju, hyperlipidemia patients, and normal subjects; however, the intake of crude fiber per 1,000 kcal in males and females was not significantly different among the four groups. Also, the dietary fiber intake(14.8-19.8g/day) and the dietary fiber intake per energy unit(7.7-10.9g/1,000kcal) were not significantly different between the four groups. The dietary fiber intakes of diabetics and hyperlipidemia patients were not significantly different from those in normal subjects, and these amounts were significantly lower than recommended levels. Thus, the methods of increasing dietary fiber intake, such as developing low-calorie, high-dietary fiber foods or additives, needs to be researched.

• Korean Journal of Community Nutrition
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• v.10 no.3
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• pp.290-302
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• 2005

The nutrients intake and health-related habits of nonagenarian subjects in Korean representative longevity belts of Damyang, Gokseong, Kurye, Sunchang were evaluated for the purpose of providing the information on the desirable food selection and dietary pattern of elderly population. A survey was conducted with 91 subjects (26 males and 65 females) and their food intakes were measured by the combination of one meal weighing and 24-hr recall, and their general background information was collected by visit. The mean age of the subjects was 93.6 $\pm$ 2.2 (male) and 97.6 $\pm$ 4.6 (female) The average smoking rate was $20.9\%$, the rate of regular drinking was $26.4\%$. The average energy intake was 1,284.9 kcal comprising $77.1\%$ of RDA for elder people over 75. The energy ratio of carbohydrate, protein and fat were 66.5 : 18.2 : 15.3. The average intake of protein, calcium, iron and zinc were $107.4\%,\;59.9\%,\;106.3\%$ and $60\%$ of RDA respectively. The lower intake of vitamins as low as $70\%$ was found except vitamin $B_6$ and niacin. The majority of the subjects consumed rice as staple diet and mostly consumed white plain rice rather than mixed grain rice. The animal and plant food intakes were 88.4 : 11.6 in males and those of females were 83.0 : 17.0 showing a tendency of plant-based meals. Nutrients that showed NAR over 0.7 were protein, iron, vitamin $B_6$, niacin and phosphate, but those with INQ over 1. Nutrient with INQ below 0.7 was only vitamin E. Even though their nutritional quantity did not appear to be enough, but their nutritional quality was relatively high. The adding dairy products, nuts and fruits for the purpose of proving sufficient vitamin and minerals can achieve the optimal nutritional intake patterns. Further research on RDA of this age population should be followed.

• Korean Journal of Community Nutrition
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• v.12 no.1
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• pp.25-39
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• 2007

The purpose of this study was to investigate the dietary intakes in middle-aged women(pre and postmenopausal) and relation to climacteric symptoms. We conducted the anthropometric measurements, climacteric symptoms survey, and dietary intake to assess the nutrient intakes. Also, dietary quality indices were evaluated. The subjects, over 40 years old, were 168 middle aged women(pre=74, postmenopausal=94), mean age was $48.9{\pm}3.6yr$. The anthropometric measurements showed that 59% of subjects were overweight and obese. Climacteric symptoms that were answered 'yes' in 50% plus in the subjects, were dry eyes, forgetfulness, difficult concentration, large joint pain(shoulder), fatique, backache, dry skin, joint pain(ankle and knee), dry mouth, dizziness, depression and lonesomeness, snore, morning stiffness, and hot flash. Some symptoms showed significant difference between pre and postmenopausal groups. The average energy intake was 1602.1 Kcal, which was 82% of the Korean EER. The subjects had lower vitamin A, riboflavin, folic acid, Fe, Zn and Ca intake than Korean RI. The lowest nutrient intake was Ca. The mean of food intake was 1294.2 g and MAR of diet quality indices was 0.83. In relation to dietary factors with climacteric symptoms, significant correlations have been found between total protein, animal protein, lipid, cholesterol and niacin intake and 'fatique', energy, carbohydrate, thiamin, vitamin B6, folic acid, vitamin C, Na, K and Fe intake and 'dry skin', Ca intake and 'difficult concentration'. Our results indicate that dietary factors(food and nutrients intake, INQ, NAR, MAR) may effect the prevention and reduction of some climacteric symptoms in middle aged women.