http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Lee Junghun,Lee Dongyeong,Lee Jaehyeong,Yoon Minhan,Jang Gilsoo 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.4
In this study, we analyzed the impact of multi-terminal direct current (MTDC) system on the integration of renewable energy resources into the Korean power system. Due to the large-scale renewable energy plants planned to be integrated into the power system, line congestion is expected in the southern part of power system. Given the difficulty in constructing AC transmission lines due to social conflicts, we proposed an alternative solution using an offshore multi-terminal DC offshore transmission system. Firstly, we calculate the effective renewable energy plant generation capacity based on annual wind and solar radiation data. Next, we conduct PSS/E simulations to minimize future line congestion in the Korean power grid. The offshore terminal is designed to transfer the power generated in southern Korea and is verified using different terminal rating cases. The simulation result, including contingency analysis, demonstrate that transferring 80% of the generated renewable power achieves the best line flow condition. Therefore, the MTDC system is a possible candidate for integrating future renewable energy systems into the Korean power grid.
한국 교육복지정책의 전개 및 향후 과제에 대한 고찰 : 이돈희의 『교육정의론』을 중심으로
이수지(Lee, Suji),김새론(Kim, Searon),전주현(Jeon, Jyhyun),한지예(Han, Jiyea),황정훈(Hwang, Junghun),엄문영(Eom, Moonyoung) 한국교육행정학회 2021 敎育行政學硏究 Vol.39 No.1
본 연구는 이돈희의 『교육정의론』에 제시된 교육복지와 교육정의의 개념을 이론적으로 고찰하고, 이를 바탕으로 국내 주요 교육복지정책이 정의롭게 운영되고 있는지를 분석하여 향후 교육복지정책에 요구되는 과제를 제시하였다. 『교육정의론』에 따르면 교육복지란 교육정의 실현의 근본적인 출발점으로서 모든 교육대상의 교육적 욕구 충족과 자아실현을 위해 유의미한 학습경험을 제공하는 것이다. 이러한 교육정의의 관점에서 무상교육, 방과 후 학교, 학습부진학생 지원, 교육복지우선지원사업, 교육소외 취약계층 지원, 고등교육 학자금 지원 정책 등 6가지 국내 주요 교육복지정책의 운영을 분석하였다. 그 결과 추후 교육복지정책에 요청되는 과제로 ‘교육소외 취약계층을 위한 교육복지의 양적 확대’, ‘교육기회의 유의미성 보장을 위한 교육복지정책’, ‘특수요소 성장을 지원하는 교육복지정책 예산 확충’, ‘수혜 대상 범위에 대한 공감대 형성’, ‘모든 학생을 대상으로 하는 교육복지정책 지향’을 제시하였다. 본 연구는 이돈희의 『교육정의론』에 관한 이론적 고찰과 정책 분석을 병행함으로써 ‘교육정의’에 대한 관심을 촉구하고, 교육복지정책이 나아갈 정의로운 방향 제시에 기여하고자 하였다. This study theoretically contemplated the concepts of educational welfare and educational justice presented in Lee, Don-hee"s 『Theory of Education Justice』, and analyzed whether major educational welfare policies in Korea are operating equitably, presenting the tasks required for future educational welfare policy making. According to the 『Theory of Education Justice』, educational welfare is a fundamental starting point for the realization of educational justice, providing meaningful learning experiences for the fulfillment of educational needs and self-realization of all educational subjects. From this perspective, six major domestic educational welfare policies were analyzed, including free education, after-school support policies, poor student support, education welfare priority support projects, support for the disadvantaged underprivileged, and higher education funding policies. As a result, the government proposed ‘Quantitative expansion of educational welfare for the underprivileged’, ‘Educational welfare policy to guarantee the significance of educational opportunities’, ‘Expansion of educational welfare policy budget to support growth of special demand’, ‘Forming a consensus for the scope of beneficiaries’, and ‘Oriented educational welfare policy for all students’. This study encouraged interest in ‘education justice’ by combining theoretical consideration of Lee, Don-hee"s 『Theory of Education Justice』 and contributed to the just direction for education welfare policy.
Flow characteristics of crushed food wastes in household sewer pipes
( Junghun Lee ),( Young Sik Park ),( Wookeun Bae ) 한국폐기물자원순환학회 2011 ISWA Vol.2011 No.0
Food wastes, generated over 14,000 ton/day in Korea, are collected and hauled separately from the other municipal solid wastes. Most of the food wastes collected are processed in the composting or feed-manufacturing facilities, of which products are hardly marketable due to its marginal value. Anaerobic digestion in the sewage treatment plants (STPs) has been suggested as an alternative to manage the food wastes. This alternative is attractive as it can generate energy and save a greater part of the collection and hauling costs, only if the food wastes are transported to the STPs via existing sewer systems. A preliminary survey revealed that the crushed food wastes, discharged through household garbage disposers, may clog the lateral sewer pipes in apartment buildings. This study was performed to investigate the food-waste components that potentially clog the sewer pipes and the factors that affect a smooth transport of the food-waste particles. Six components of food-wastes, salted cabbages (mimic of Kimchi), brown seaweeds, rinds of a watermelons, rice grains, egg shells, and chicken bones, were prepared, and discharged individually or as a mixture into a transparent PVC pipe (Ø100 mm, L 9 m), after crushing by a commercial household garbage disposer. The PVC pipe had a slope of 1/100, 1/200, 1/400, or 0 and was equipped with an intentional hurdle whose hight was 0 (no hurdle), 1, 3, or 5 cm. The flow velocity of water in the pipe was controlled at approximately 0.1, 0.3, or 0.6 m/s. The results clearly revealed that food wastes with a relatively low density such as salted cabbages, brown seaweeds and rinds of watermelons flew well through the pipe even at 0.1 m/s of water flow velocity with any slope. The crushed salted cabbages flew well even with a 5-cm hurdle. The crushed brown seaweeds needed a higher water flow velocity (0.6 m/s) to clear a 5-cm hurdle. On the other hand, food wastes with higher density such as rice, egg shells and chicken bones were hardly transportable in the pipe even at 0.6 m/s of water flow velocity and with a 1/100 slope. A mixture of the food-waste components showed similar results: Smooth flow of lighter ones and deposition of heavier ones. In summary, the crushed food wastes with lower density are well transported through a household sewer pipe, while those with higher density are not and, thus, should not be introduced to a garbage disposer.
Thermal performance evaluation of low-income buildings based on indoor temperature performance
Lee, Junghun,Kim, Seohoon,Kim, Jonghun,Song, Doosam,Jeong, Hakgeun Elsevier 2018 APPLIED ENERGY Vol.221 No.-
<P><B>Abstract</B></P> <P>In South Korea, about 40,000 buildings of low-income households have been diagnosed and remodeled annually by the Energy Welfare Program, using the normative method. The normative method is based on the heat gain elements of a building. In contrast, the performance-based method is based on the output derived from the thermal performance of each building part. In the normative method, there is no other building in which the input conditions of a building are perfectly matched. Further, cost-effective energy remodeling strategies vary according to the capacity of the diagnosis engineer. In this paper, we analyze the thermal performance of buildings by the performance-based method using indoor temperature, and examine the possibility of a database for the optimal remodeling method. For this, we analyzed more than 2500 simulation cases by combining thermal performance of each building part. The indoor temperature pattern can be similar even when the thermal performance of each building part is different. In buildings with similar indoor temperature patterns, the coefficient of variation of the root mean squared error of energy demand falls within the acceptable error range. Furthermore, changes in energy demand and predicted mean vote are similar when window thermal performance is changed.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Indoor temperature pattern can be similar even building conditions are different. </LI> <LI> If similar indoor temperature patterns occur, energy demand is also similar. </LI> <LI> Changes in energy demand are similar when window thermal performance is changed. </LI> <LI> Overall thermal performance of low-income buildings can be diagnosed. </LI> <LI> Databases can store remodeling plans using indoor temperature for future use. </LI> </UL> </P>