태양열급탕시스템의 집열기 배열에 따른 에너지성능 분석 및 평가

고명진(Ko Myeong-Jin),임보민(Lim Bo-Min),김용식(Kim Yong-Shik) 한국태양에너지학회 2016 한국태양에너지학회 논문집 Vol.36 No.4

The objective of this work is to analyze the variation in energy performance for each flat plate collector connected in series. In this study, it was assumed that solar water heating system with annual solar fraction of 60% was installed in an office building in Seoul, South Korea. The transient energy performance corresponding to four cases, which are selected using different solar radiation and outdoor air temperature, is studied by analyzing the variation in outlet temperature, solar useful heat gain, and thermal efficiency of each collector. It is observed that the useful heat gain and the collector efficiency decrease continuously, and outlet temperature increases when increasing the number of collector connected in series. The long-term performance is assessed by evaluating the thermal efficiency of each collector for two solar radiation conditions ranging from 780 to 820 W/㎡ and from 380 to 420 W/㎡. It is found that the differences between the intercept and slope of the efficiency curves for first and eighth collectors are 3.68% and 6.74% for solar radiation of 800 ± 20 W/㎡ and 8.57% and 12.90% for solar radiation of 400 ± 20 W/㎡, respectively. In addition, it is interesting to note that annual useful heat gain and collector efficiency are reduced with similar rate of about 6.13% when increasing the collector area by connecting the collectors in series.

ISO 9869-1의 평균법에 의한 겨울철 공동주택 외벽의 현장 열관류율 수렴성 분석

고명진(Myeong-Jin Ko),이예지(Ye-Ji Lee),최두성(Doo-Sung Choi) 한국생활환경학회 2018 한국생활환경학회지 Vol.25 No.5

This study analyze the convergence of the in-situ thermal transmittance calculated by average method following ISO 9869-1 to the increase and change of measurement period. The measurement was conducted for an opaque exterior wall of an apartment house over a period of two weeks during winter. As a results of the measurement, the termination conditions were satisfied after eight days, more than twice the minimum required measurement period of three days, even though the experimental conditions recommended in ISO 9869-1 were met. The findings show that as the measurement duration(DT) increased, the termination condition that the thermal resistance obtained at the end of the test must not deviate by more than ±5% from the value obtained 24 h earlier, were easily achieved. On the other hand, other termination condition that the thermal resistance obtained by analyzing data from the first time period during INT(2×DT/3) days must not deviate more than ±5% from the value obtained from the data for the last period of the same duration are relatively difficult to achieve. This is because the environmental parameters of the first and last time periods must be similarly maintained within a stable range.

주상복합 건물의 투입자재에 대한 LCI DB 구축

고명진(Myeong-Jin Ko),전흥찬(Hung-Chan Jeon),조균형(Kyun-Hyong Cho),최두성(Doo-Sung Choi) 한국생활환경학회 2015 한국생활환경학회지 Vol.22 No.6

This study, targeting the residential-commercial building which is recently emerging as the representative residential facility of urban area, analyzed the characteristics of environmental impact of input materials making up a building using LCA method, and constructed LCI DB for input materials. As a result of the analysis of Complex 8 (31 buildings), the average environmental impact of the residential-commercial building was found to be 9.67E-02 pe·yr/m², being analyzed high in the order of civil (38.5%), architecture (33.1%), landscape (13.8%), mechanical (8.7%) and electric&telecommunication construction (5.9%). In addition, through the sensitivity analysis of the case buildings, this study selected major materials for 15 sorts of buildings, 3 sorts of civil construction, and 1 sort of landscape construction, and the average environmental impact of other materials excluding the selected major materials was analyzed as 2.48E-02pe·yr/m² for a building, and 2.61E-02pe·yr/m² for a site.

보육시설 적용 지열히트펌프시스템의 하절기 운전특성 및 에너지성능 실증평가

고명진(Myeong-Jin Ko),김용식(Yong-Shik Kim) 한국생활환경학회 2015 한국생활환경학회지 Vol.22 No.5

To spread the application of ground source heat pump (GSHP) systems, this paper carried out empirical evaluation of operation characteristics and energy performance of the GSHP system. The GSHP considered in this study has a cooling capacity of 89.7㎾ and a heating capacity of 93.5㎾, and coefficient of performance (COP) in cooling mode of 4.7 and COP in heating mode of 3.5. From the monitoring results in summer season, it was observed that average daily temperatures of liquid entering the load side of the GSHP were measured to be 9.5℃, 8.7℃ and 10.1℃ in typical day from June to August that were sufficient to ensure proper cooling to the building. In the same days, average daily temperatures of liquid entering the source side of the GSHP were measured to be 17.56℃, 20.1℃ and 21.5℃. Although the temperature was increased about 4℃ due to the continued cooling operation of approximately 3 months, it was still lower than 25℃ generally evaluated as stable operation condition in cooling mode. In addition, it was found that the GSHP system shows a high energy performance because average COP and system COP for analysis period were computed at 7.1 and 4.4 higher than the nominal value, respectively.

6 ㎾급 계통연계형 태양광발전시스템의 하절기 에너지성능 실증평가

고명진(Myeong-Jin Ko),김용식(Yong-Shik Kim),신의혁(Eu-Hyuk Shin),김천학(Chun-Hag Kim) 한국생활환경학회 2015 한국생활환경학회지 Vol.22 No.5

This paper carried out empirical evaluation on generating characteristics and energy performance of 6 ㎾ grid-connected photovoltaic (PV) system in summer season. The PV system was installed to provide power for lighting and appliance of a nursery accommodating about 100 children and teachers. According to the analysis of the monitoring data, average daily solar irradiance was measured to be 5.44, 2.82 and 4.98 ㎾h/㎡ from June to August, respectively. Meanwhile, average daily power generation of the system was computed to be 29.5, 14.3 and 25.8 ㎾h for each month, and the minimum and maximum values during three months were computed to be 1.2 and 36.4 ㎾h. Therefore, it is considered the power output of the PV system is closely related to the variation in solar radiation. In addition, it was observed that average daily load-sharing ratio of the system was 24, 4 and 25% in each typical day, and average weekly load-sharing ratio was 32, 15 and 23% in each typical week. Therefore, this results show that grid-connected systems is more suitable than stand-alone system in case of last rainy days during the summer season aside from the advantage that are not necessary to install an expensive battery.

시뮬레이션을 이용한 사무소건물 적용 태양열 급탕시스템의 에너지성능 분석

고명진(Ko Myeong-Jin),최두성(Choi Doo-Sung),김용식(Kim Yong-Shik) 한국태양에너지학회 2009 한국태양에너지학회 학술대회논문집 Vol.- No.-

This paper is to simulate a solar hot water heating system used in a medium-scale office building using the dynamic simulation. This study is focused chiefly on the annual variation of energy performance, the solar fraction with respect to the difference of hot water load temperature. For this purpose the simple model of a solar hot water heating system has been considered with TRNSYS program and the simulations were performed with the weather data in Seoul, Korea. The share ratio of solar hot water system of the summer season appeared higher than the winter season because that the decrease of the domestic hot water load was far despite the relative decrease of the solar radiation. As the temperature was lower from 60℃ to 50℃, the solar fraction increases 8.1 percent due to 20- percent decrease of annual hot water load.

개발 IE4급 2.2㎾ 유도전동기의 기계적 특성분석에 관한 연구

고명진(Myeong-Jin Ko),박순섭(Soon-Sub Park) 대한기계학회 2020 대한기계학회 춘추학술대회 Vol.2020 No.7

국내외 7.5㎾ 유도전동기 기계적 특성 분석에 관한 연구

고명진(Myeong-Jin Ko),박순섭(Soon-Sub Park) 대한기계학회 2020 대한기계학회 춘추학술대회 Vol.2020 No.7

초등학교 아동의 거절민감성과 주의조절이 학교생활적응에 미치는 영향

고명진(Ko, Myeong jin),이숙(Lee, Sook) 한국부모놀이치료학회 2020 한국부모놀이치료학회지 Vol.- No.10

This study researched a general trend on rejection sensitivity of the elementary school child, attention control and school life adaptation targeting fifths and sixths grade of elementary school. this paper conducted hierarchical multiple regression analysis to see the influence of socio-demographic characteristics according to the school life adaptation, rejection sensitivity of the elementary school child, and attention control after calculating ‘the Pearson correlation efficient. Below is a summary of the research results. First, with regard to a general trend on school life adaptation that appeared with the higher levels than the average score of each point in the following order. As for rejection sensitivity appeared with a lot of lower levels than the average score of each point in the following order. About attention control appeared with a little higher levels than the average score of each point. Second, with regard to result that the higher economic level a child perceived in the more a child is well-adjusted to a school life. And the higher level a child has based on attention control, , the more a child is well-adjusted to a school life. Third, as a result of conducting hierarchical regression analyses to evaluate the influence of socio-demographic characteristics rejection sensitivity of the elementary school child. Fourth, the high rejection sensitivity of the elementary school child appeared to have negative effects on school life adjustment. Fifth, attention shift, a lower variable of attention control, appeared to be in any meaningful impact on relationships with friends, a lower variable of school life adaptation. This study ensures the importance of rejection sensitivity and attention control for a better school life adaptation by lightening the effect of rejection sensitivity of the elementary school child and attention control on school life adaptation.

2.2kW 유도전동기의 회전자 타입에 따른 기계적 특성에 관한 연구

고명진(Myeong-Jin Ko),박순섭(Soon-Sub Park) 대한기계학회 2021 대한기계학회 춘추학술대회 Vol.2021 No.4

본 논문에서는 IE4 급 2.2kW 유도전동기 개발을 위해 고정자, 회전자, 하우징, 베어링 앞/뒤 커버, 축계, 냉각팬을 설계 및 제작하였다. Al 다이캐스팅, Cu 다이캐스팅, Al-Cu Hybrid 3 가지 타입의 회전자를 적용한 2.2kW 유도전동기를 개발하였고 각 전동기의 기계적 특성(소음, 진동, 풍속, 공극, 효율)을 분석하고 해외 선진사 제품과 비교하였다. 2.2kW 개발 유도전동기 Al 다이캐스팅 회전자의 경우 소음을 58.4 → 54.0 dB 로, Cu 다이캐스팅 66.3 → 56.2 6 dB 로 Al/Cu Hybrid 회전자 70.3 → 66.8 dB 로 약 5~15 % 소음을 저감 시켰다. 고정 테이블 진동의 경우 Al 다이캐스팅 1.845 → 1.649 ㎛, Cu 다이캐스팅 2.464 → 2.232 ㎛으로 약 10 % 고정 테이블 진동을 개선시켰다. 유도전동기의 효율 저하의 원인이 되는 소음/진동 개선을 위한 미세절입 가공기술 적용으로 축 흔들림 (21 ㎛ → 10 ㎛ 이하) 약 50 % 감소시켰으며 기존 양산업체 밸런싱 기준 개선(0.8 g → 0.4 g) 약 50 % 감소시키는 효과를 보였다. 다이나모미터를 활용하여 손실분리 시험규격 KS C IEC60034-2-1에 근거하여 전동기 효율 측정 결과 Al 다이캐스팅 91.0 %, Cu 다이캐스팅 91.8 %로 IE4 급 달성하였다. 추후 Al-Cu Hybrid 회전자가 적용된 2.2kW 유도전동기 개발 이 가능 할 것으로 사료된다.