• 응용통계연구
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• 제29권7호
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• pp.1373-1383
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• 2016

풍력에너지 산업이 발전하고 풍력발전에 대한 의존율이 높아짐에 따라 안정적인 공급이 중요해지고 있다. 원활한 전력수급계획을 세우기 위해서 풍력발전량을 정확히 예측하는 것이 중요하다. 본 논문에서는 강원도 평창 횡계리에 설치된 대관령 2풍력(2MW 1기)의 시간별 풍력발전 데이터와 강원도 대관령 기상대에서 관측되는 시간별 풍속과 풍향 데이터를 기상청 지상관측자료에서 수집하여 연구하였다. 풍력발전량 예측을 위하여 신경망 모형과 시계열 모형인 ARMA, ARMAX, ARMA-GARCH, Holt Winters 모형을 비교하였다. 모형 간 예측력을 비교하기 위해 mean absolute error(MAE)를 사용하였다. 모형의 예측 성능 비교 결과 1시간에서 3시간의 단기 예측에 있어서 ARMA-GARCH 모형이 우수한 예측력을 보였다. 6시간 이후 예측에서는 신경망 모형이 우수한 예측을 보였다.

• 자원환경지질
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• 제23권3호
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• pp.309-322
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• 1990

지난 20년간(年間) 한국경제(韓國經濟)의 지속적(持續的)인 산업발전(産業發展)은 광물자원(鑛物資源)의 대량소비시대(大量消費時代)를 이룩하였다. 그러나 이와 같은 소비(消費)의 급성장(急成長)은 대부분(大部分) 외국(外國)으로부터의 수입(輸入)에 의존(依存)하였다· 한국(韓國)에서는 330여(余) 광종(鑛種)이 알려져왔으며, 그중에서 50여종(種)이 산업원료(産業原料) 광물자원(鑛物資源)으로 이용(利用)되고 있다. 1988년(年) 연료광물자원(燃料鑛物資源)을 제외(除外)한 전체(全體) 금속(金屬) 비금속(非金屬) 원료광물자원(原料鑛物資源)의 국내(國內) 자급도(自給度)는 29% 였고, 26종(種)의 비금속(非金屬) 광물(鑛物)은 그 자급도(自給度)가 66%로 비교적(比較的) 높은 편이나, 18종(種)의 금속광물(金屬鑛物)의 경우는 그 자급도(自給度)가 6.3%에 불과한 실정(實情)이다. 1970년대(年代) 이후(以后) 우리나라의 경제발전(經濟發展) 단계에서 국민총생산량(國民總生産量)과 광물소비(鑛物消費)와의 관계는 아주 완만한 변화양상(變化樣狀)을 보이고 있다.

• 한국식품영양학회지
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• 제20권4호
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• pp.467-475
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• 2007

The nutritional status and chronic disease occurrence of the elderly living in local areas is affected by certain factors, including low energy intakes, low food diversity, poor nutritional quality and living alone. Moreover, elderly people who live alone may have low incomes and be socially isolated. Thus, we have provided them adjustable and balanced menus using standard recipes. In this study, we investigated aspects of nutritional status and living conditions in the elderly status, in relation to food, activities of daily living(ADL), nutrition risk index, average intake of calories and nutrients, the mini dietary assessment index score, depression score, menu satisfaction, menu demand, satisfaction with menu offerings. The result indicated significant nutritional improvements by providing menus to the elders and suggest that by providing adjustable and balanced menus using standard recipes, the nutritional status of isolated elders can be changed and improved.

• 분석과 대안
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• 제5권2호
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• pp.77-105
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• 2021

Потребление природного газа в Азии растет быстрыми темпами из-за различных факторов, таких как экономический рост в регионе, урбанизация, переход с угля на газ в секторах производства электроэнергии и промышленности. Из-за географических особенностей и отсутствия международных трубопроводных соединений между странами в АТР большая часть природного газа, экспортируемого азиатским потребителям, транспортируется танкерами по морю в виде сжиженного природного газа. Поскольку азиатский рынок является наиболее прибыльным рынком с самым быстрым ростом спроса, конкуренция между продавцами сжиженного природного газа (СПГ) за долю азиатского рынка усиливается. Конкуренция ускорилась, особенно после того, как на рынок были выведены большие объемы дополнительных поставок со стороны новых экспортеров из США, Австралии и России. Cheniere Energy, первый экспортер СПГ в континентальной части США, не приняла традиционный механизм ценообразования и бизнес-модель. Традиционно цены по долгосрочным контрактам на СПГ индексируются к ценам на конкурирующие виды топлива, такие как сырая нефть. Компания приняла механизм ценообразования и бизнесмодель по системе «кост-плюс». Cheniere Energy выбрала более безопасную и безрисковую систему ценообразования, которая ежегодно гарантирует продавцу фиксированную сумму дохода. Компания зарабатывает одинаковую сумму денег, независимо от динамики цен на природный газ на внутреннем и международном рынке, возможно с меньшим доходом. Однако, успешно внедрив более безопасную и безрисковую бизнес-модель, Cheniere Energy, компания относительно меньшего размера по сравнению с крупными нефтегазовыми компаниями, стала примером для других небольших компаний в стране. Бизнес-модель компании продемонстрировала, как войти и управлять бизнесом СПГ в США в условиях растущей конкуренции между продавцами на внутреннем и международном рынке.

• 전기학회논문지
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• 제64권5호
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• pp.667-679
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• 2015

The bearer of the power sector's ETS compliance cost is power consumer for the following reasons. Firstly, power companies are constrained in establishing appropriate strategies to comply with ETS regulations due to the structural differences between the domestic power market and emission trading system. In other words, because power companies do not have a right to determine price and production of electricity, they have to compete with other companies under disadvantaged conditions in the emission trading market. Secondly, because ETS compliance cost is part of power production costs as it is also clearly written in the national greenhouse gas reduction road-map and the second energy supply plan, the cost should be included in power price following the power market operation rule. Thirdly, the most effective method to reduce carbon emissions in power sector is to reduce power demand, which is efficiently achieved through raising power price to a realistic level. Low power price in Korea is the major cause of rising power demand which is also the major cause of rising GHG emission. Therefore, power sector's ETS compliance cost should be included in power price to encourage power consumers' actions on reducing power consumption. Fourthly, when externality cost occurs in the process of delivering public services, usually beneficiary pay principle is applied to identify the cost bearer. Since electricity is one representative public good, the bearer of power sector's ETS compliance cost is power consumer.

• 환경위생공학
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• 제6권2호
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• pp.59-68
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• 1991

The word of stress was wsed in the field of physics as a external force from 17th century, but the meaning of this stress had chafed to the internal and exteral demand fort the human body in medical area. All the stumulants which make stress was called as j stressor. When animals get stress blucose excreted from liver to adapt for the emergent state ant some related hormone secrete convert protein and lipid to glucose for the purpose of energy supply to muscle. As a results heart rate, blood pressure, respiration rate are increased and musclse are strengthed. These physiolgical reactions ate controlled by autonomic nerve system under the control of hyothalamus in brain. Autonomic nerve system and endocrinary system are react harmoiously to stress reaction. According to the stress reaction, adrenomedullary system are stimulated, and epinephrine, morepinephrine are exceted. Author experimented the effect of the immobilizational stress to rat by analyzing the variaition of catecholamine secrction, the Na concentration and the effect of the antistresf effect by Panax Ginseng which is a traditional Korean herb medicine. The concentration of the norepinephrine, epinephrin, and dopamin in normal rat are 1 578 ng/ml, 0.365 ng/ml, and 0.731 ng/ml respectively, but in the immobilyzed stress groIn the concentration were increased to 1.915 ng.ml, 0.854 ng/ml, and 2,361 ng/ml which she the high show the higher concentration of catecholamine to stressor.

• 한국주거학회논문집
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• 제21권1호
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• pp.1-9
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• 2010

Housing problems in city have being caused social contradiction that contains social discord and conflict between poor and rich. And they have raised one of social problems including a disequilibrium of demand and supply, a housing trouble, and a poor residential environment. Therefore, the purpose of this study is to suggest to the improvement of social housing that exposes to a poor environment for social integration. For this, this study is to extract environmental-friendly design factors for each building phase by in-depth evaluation of experts, and to analyze the problems of domestic social housing and environment-friendly design factors considered prior literature. The results as follow. It might be considered highly phase of schematic design, The building construction, and performance management having factors. Specially, it analyzed to 'Living Environment', 'Economic Efficiency', and 'renewable Energy Systems' should be considered highly. Ultimately, this study would be reconsidered the improvement of social housing proposed by the Government for the social outcast.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.228-229
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• 2018

In the construction industry, we have set goals such as reduction of greenhouse gas emissions and reduction of energy use. In particular, reduction of CO₂ emissions in the concrete manufacturing process, reduction of industrial waste and industrial wastes into concrete The zero-emission level of reuse as a resource is under review. On the other hand, the cost of stone is expensive due to small quantity production of domestic stone production in order, it is difficult to carry and construct with heavy material, and it takes long time to construct. In order to solve the shortage of supply and demand of natural stone, various kinds of stone powder, artificial stone made by putting stone texture on the surface of mortar or concrete, fiber reinforced plate, tiles and the like are increasingly used. In this study, the artificial stone using slag and recycled aggregate instead of natural stone was fabricated and the strength characteristics were evaluated for its applicability and feasibility.

• 한국전기전자재료학회논문지
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• 제31권4호
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• pp.255-260
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• 2018

In recent years, increasing electricity use has led to considerable interest in green energy. In order to effectively supply, cut off, and operate an electric power system, many electric power facilities such as gas insulation switch (GIS), cable, and large substation facilities with higher densities are being developed to meet demand. However, because of the increased use of aging electric power facilities, safety problems are emerging. Electromagnetic wave and leakage current detection are mainly used as sensing methods to detect live-line partial discharges. Although electromagnetic sensors are excellent at providing an initial diagnosis and very reliable, it is difficult to precisely determine the fault point, while leakage current sensors require a connection to the ground line and are very vulnerable to line noise. The partial discharge characteristic in particular is accompanied by statistical irregularity, and it has been reported that proper statistical processing of data is very important. Therefore, in this paper, we present the results of analyzing ${\Phi}-q-n$ cluster distributions of partial discharge characteristics by using K-means clustering to develop an expert partial discharge diagnosis system generated in a GIS facility.

• 전기학회논문지P
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• 제64권4호
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• pp.337-342
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• 2015

The company of 4 core materials that are needed for photovoltaic generation is located in area around this university in Gunsan, Saemangeum. And also, it was almost completed the value chain about the production of Polysilicon, Ingot, Wafer, modules and the design, construction of generation system. The industry-academy-government has understood that because of the relative companies' production and investment, it leads to a supply and demand of manpower and thus will have field centered manpower education. This program will help the problem of lack of manpower in relative companies by establishing competitive major agreement like vocational education system. Also, the university and the participating company in joint have pushed ahead field business education to make the least of industrial-education's mismatch, the training of professional manpower connected with related industries to make the universities chemical characteristics, companies securing excellent manpower and contributed to the revitalization of the regional economy. In this paper, are aware that photovoltaic industry is a future strategic industry for the country, so we will train the immediately site adapting manpower for the area of photovoltaic material and system as our goal. This is shown results of education operation for 4 years.