• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.436-443
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• 2017

Recently, the development of new energy technologies has become a hot topic due to problems,such as global warming. Unlike renewable energy technologies, such as solar energy generation, solar power, and wind power, which are optimized to achieve medium or above output power, the output power of energy harvesting technology is very small and has not received much attention. On the other hand, as the mobile industry has been revitalized recently, the utility of energy harvesting technology has been reevaluated. In addition, the technology of tracking the maximum power point has been actively researched. This paper proposes a new MPPT(Maximum Power Point Tracking) control method for a TEM(thermoelectric module) for load resistance. The V-I curve characteristics and internal resistance of TEM were analyzed and the conventional MPPT control methods were compared. The P&O(Perturbation and Observation) control method is more accurate, but it is less economical than the CV (Constant Voltage)control method because it usestwo sensors to measure the voltage and current source. The CV control method is superior to the P&O control method in economic aspects because it uses only one voltage sensor but the MPP is not matched precisely. In this paper, a method wasdesigned to track the MPP of TEM combining the advantages of the two control method. The proposed MPPT control method wasverified by PSIM simulation and H/W implementation.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.586-591
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• 2005

우리나라는 에너지의 안정적 공급과 에너지이용 과정에서 발생하는 환경적, 안보적 외부성을 최소화하는 에너지수급 구조를 마련하기 위해 2003년 12월 '제2차 신재생에너지 기술개발 및 이용보급 기본계획(2003-2012)'을 발표하였다. 이 계획에서는 2011년까지 전체 TPES의 $5\%$를 신재생에너지로 공급하는 것을 정책목표로 수립하고 수소, 태양광 그리고 풍력기술을 중점적으로 추진하기로 하였다. 특히 수소부문에서는 주택 및 건물용, 발전용, 수송용 연료전지의 개발을 중심으로 개발하여 세계 기술시장의 $20\%$를 확보한다는 계획을 발표하였다. 이러한 기술 잠재력을 기반으로 우리 정부도 미국이나 일본과 같이 수소경제로의 전환을 준비하고 있으며 2020년대 이후 우리나라의 에너지부문은 새로운 국면에 접어들 것으로 전망된다. 에너지나 환경기술의 효과적 인 개발을 위해서는 이들 기술의 직접적인 비용측면에 대한 분석 즉 경제성 평가와 새로운 기술변화로 인한 중장기적인 사회경제적 영향평가가 선행되어야 한다. 이러한 평가는 대상 기술의 사회경제적 파급효과가 광범위할수록 더욱 복잡한 분석이 요구된다. 본 연구의 주제인 수소에너지기술은 지금까지 이용되던 것과는 전혀 새로운 에너지캐리어(carrier)를 개발하는 것으로 에너지부문 및 여타 다른 산업부문이 공유하고 있는 에너지 관련 인프라의 전면적인 조정이 요구되며 에너지 이용과 관련된 사회경제적 측면의 급속한 변화를 수반한다. 본 연구는 수소경제로의 이행에 대한 사회경제적 영향평가의 방법론적 요소들과 기법을 제시한다."중등도 독성"으로 나타났다 이상의 결과는 전기도금을 이용하여 교정용 선재의 직경을 증가시키는 방법이 임상에 적용되기 위해서는 세포독성을 줄이기 위한 추가의 연구가 필요함을 시사하였다.의하게 가장 낮은 정지. 운동 마찰력을 보였고 브라켓-호선 각도가 증가함에 따라 유의하게 정지, 운동 마찰력도 증가하였다 (P<0.001)%$ 낮추지만(p value=0.260) 평균 $D_{max}$는 거의동일 하여($0.3\%$ 감소, p value=0.867), 전통적인 방법보다 우수성이 크게는 없는 것으로 평가되었다. 그러나 환자의 체곡선이 보상체와 잘 일치하는 경우에는 DII가 $18\%$까지 감소하였다. 결론 : Multistatic field 방법은 모든 환자에 대하여 선량분포의 균일성을 전반적으로 향상시키는 효과적인 방법으로 평가되는 반면 공용보상체의 사용은 보상체의 크기가 환자의 체 윤곽과 잘 일치하는 경우만 효과적으로, 적용의 범위에는 한계가 있는 방법으로 평가되었다.비교하여 계통에 따르는 차이가 있음을 알 수 있었다. 그러므로 가임기 여성의 방사선 진단 및 치료시 Rugh의 10일 법칙을 적용하여 착상전기 방사선 조사로 인한 부작용들을 적극적으로 예방하는 것이 매우 중요하다고 생각한다.equirements of the prematured infants during the early weeks of life. 모든 치근단 수준에서 비표준화 medium 크기 master cone 사용군이 ISO 표준화 규격의 master cone 사용군에 비해

• Journal of Energy Engineering
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• v.23 no.4
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• pp.31-40
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• 2014

The Korean government made the 2nd Energy Basic Plan to achieve 11% of new and renewable energies distribution rate until 2035 as a response to cope with international discussion about greenhouse gas emission reduction. Renewable energies include solar thermal, photovoltaic, bioenergy, wind power, small hydropower, geothermal energy, ocean energy, and waste energy. New energies contain fuel cells, coal gasification and liquefaction, and hydrogen. As public and private investment to enhance the distribution of new and renewable energies, it is necessary to clarify the economic effects of the new and renewable energies sector. To the end, this study attempts to apply an input-output analysis and analyze the economic effects of new and renewable energies sector using 2012 input-output table. Three topics are dealt with. First, production-inducing effect, value-added creation effect, and employment-inducing effect are quantified based on demand-driven model. Second, supply shortage effects are analyzed employing supply-driven model. Lastly, price pervasive effects are investigated applying Leontief price model. The results of this analysis are as follows. First, one won of production or investment in new and renewable energies sector induces 2.1776 won of production and 0.7080 won of value-added. Moreover, the employment-inducing effect of one billion won of production or investment in new and renewable energies sector is estimated to be 9.0337 persons. Second, production shortage cost from one won of supply failure in new and renewable energies sector is calculated to be 1.6314 won, which is not small. Third, the impact of the 10% increase in new and renewable energies rate on the general price level is computed to be 0.0123%, which is small. This information can be utilized in forecasting the economic effects of new and renewable energies sector.

• Journal of Korean Home Economics Education Association
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• v.28 no.3
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• pp.1-16
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• 2016

The purpose of this study was to develop and evaluate the teaching-learning process plan of senior cohousing to improve understanding of active and independent living in later life through Home Economics subject. The plan consisting of 5 lessons has been developed and implemented according to the ADDIE model. Various activity materials (28 individual activity sheets, 2 working sheets, and 26 teacher's reading texts) and visual materials (4 sets of pictures & photos and 10 moving pictures) as well as questionnaire were developed for the 5-session lessons. The plans were implemented to 6 classes 150 freshmen of P high school in Jeju-do during August 17th to 3rd of September, 2015. Students were highly satisfied regardless of gender with the whole 5-lessons in the aspects such as the level of participation in the lesson, understanding of the contents, adequacy of materials and activities, and usage in their future life. Students also reported that they highly accomplished the goal of each lesson to reinforce the understanding on necessity of preparing later life, senior cohousing, and senior friendly business. It can be concluded that the teaching learning process plan for senior cohousing would improve understanding and practical competency of active and independent living in later life with senior neighbors through the home economics subject.