허프 변환을 이용한 차선 이탈 경고 시스템

유성열(Sung-Yeol Yoo),김홍중(Hong-Jung Kim),명재성(Jae-Sung Myoung),박경춘(Jingchun-Piao),신현철(Hyunchul-Shin) 한국정보과학회 2015 한국정보과학회 학술발표논문집 Vol.2015 No.6

Mn조성비(組成比)가 PEMFC용(用) Pt/C 전극촉매(電極觸媒) 특성(特性)에 미치는 영향(影響)에 관(關)한 연구(硏究)

유성열,강석민,이진아,이충균,유호진,Yoo, Sung-Yeol,Kang, Suk-Min,Lee, Jin-A,Rhee, Choong-Kyun,Ryu, Ho-Jin 한국자원리싸이클링학회 2012 資源 리싸이클링 Vol.21 No.2

$Pt_{10}$/C, $Pt_9Mn_1$/C, $Pt_7Mn_3$/C electrocatalysts for Polymer Electrolyte Membrane Fuel Cells(PEMFCs) were synthesized by reduction with HCHO and their activity as a oxygen reduction reaction(ORR) was examined at half cell. The electrochemical oxygen reduction reaction(ORR) was studied by using a glaasy carbon electrode through cyclic voltammetric curves(CV) in a 1 M $H_2SO_4$ solution. The ORR activities of $Pt_9Mn_1$/C were higher than $Pt_{10}$/C, $Pt_7Mn_3$/C. Also potential-current curves of $Pt_9Mn_1$/C at 0.9, 0.8, 0.7, 0.6V for 5minutes respectively were higher than $Pt_{10}$/C, $Pt_7Mn_3$/C. Physical characterization was made by using x-ray diffraction(XRD) and transmission electron microscope(TEM). The TEM images of $Pt_9Mn_1$/C, $Pt_{10}$/C catalysts showed homogenous particle distribution with particle size of about 2.7 nm, 3 nm respectively and then the XRD results showed that the crystalline structure of the synthesized catalysts are seen FCC structure. 기존 Pt/C 전극촉매 제조시 사용되는 Pt를 일정량의 Mn으로 대체하여 PtMn/C 전극촉매를 제조하였다. 환원제로 포름알데히드(HCHO)를 사용하여 화학환원법으로 $Pt_{10}$/C, $Pt_9Mn_1$/C, $Pt_7Mn_3$/C 촉매를 제조하였으며 반쪽 전지(half cell)에서 순환전압전류와 대시간 전류를 측정하였다. $Pt_9Mn_1$/C촉매가 $Pt_{10}$/C, $Pt_7Mn_3$/C촉매보다 높은 산소환원반응(oxygen reduction reaction)을 보였으며 0.9, 0.8, 0.7, 0.6V에서 각각 5분동안 측정한 대 시간 전류측정에서 $Pt_9Mn_1$/C가 $Pt_{10}$/C, $Pt_7Mn_3$/C촉매보다 높은 활성을 나타냈다. 물리적 특성은 XRD, TEM분석을 통하여 알아보았으며 입자의 평균 크기는 $Pt_9Mn_1$/C, $Pt_{10}$/C가 각각 2.7 nm, 3 nm를 나타냈다. XRD분석을 통하여 Pt의 FCC(Face Centered Cubic)결정 구조를 확인할 수 있었다.

Polymer Electrolyte Membrane Fuel Cells용 Pt/C 캐소드 전극촉매 특성에 미치는 반응 온도

유성열,강석민,이진아,이충균,류호진,Yoo, Sung-Yeol,Kang, Suk-Min,Lee, Jin-A,Rhee, Choong-Kyun,Ryu, Ho-Jin 한국재료학회 2011 한국재료학회지 Vol.21 No.3

This study is aimed to increase the activity of cathodic catalysts for PEMFCs(Polymer Electrolyte Membrane Fuel Cells). we investigated the temperature effect of 20wt% Pt/C catalysts at five different temperatures. The catalysts were synthesized by using chemical reduction method. Before adding the formaldehyde as reducing agent, process was undergone for 2 hours at the room temperature (RT), $40^{\circ}C$, $60^{\circ}C$, $80^{\circ}C$ and $100^{\circ}C$, respectively. The performances of synthesize catalysts are compared. The electrochemical oxygen reduction reaction (ORR) was studied on 20wt% Pt/C catalysts by using a glassy carbon electrode through cyclic voltammetric curves (CV) in a 1M H2SO4 solution. The ORR specific activities of 20wt% Pt/C catalysts increased to give a relative ORR catalytic activity ordering of $80^{\circ}C$ > $100^{\circ}C$ > $60^{\circ}C$ > $40^{\circ}C$ > RT. Electrochemical active surface area (EAS) was calculated with cyclic voltammetry analysis. Prepared Pt/C (at $80^{\circ}C$, $100^{\circ}C$) catalysts has higher ESA than other catalysts. Physical characterization was made by using X-ray diffraction (XRD) and transmission electron microscope (TEM). The TEM images of the carbon supported platinum electrocatalysts ($80^{\circ}C$, $100^{\circ}C$) showed homogenous particle distribution with particle size of about 2~3.5 nm. We found that a higher reaction temperature resulted in more uniform particle distribution than lower reaction temperature and then the XRD results showed that the crystalline structure of the synthesized catalysts are seen FCC structure.

교사의 교육과정 분석 현상 탐구

유성열(Yoo Sung-yeol),이찬희(Lee Chan-hee),남승종(Nam Seung-jong),김상헌(Kim Sang-heon),정광순(Jung Gwang-soon) 학습자중심교과교육학회 2021 학습자중심교과교육연구 Vol.21 No.3

이 연구는 교사가 교육과정을 분석하는 현상을 드러내기 위해 2020년 10월 12일 부터 2020년 12월 20일까지 12명의 전문가 집단을 대상으로 하는 델파이 연구를 통하여 실시되었다. 연구 결과 첫째, 1차 델파이에서는 ‘교육과정을 분석할 때, 무엇을 어떻게 분석하는가’를 개방형으로 설문하여, 총 127문항(무엇을 69개, 어떻게 58개) 을 얻었다. 둘째, 2차 델파이는 1차의 결과를 3개의 영역으로 범주화하여, 총 62개의 문항을 얻었다. 셋째, 3차 델파이는 내용타당도(CVR)를 통해서 45개, 다시 합의도를 고려해서 최종 28개 문항을 확정했다. 이 결과를 바탕으로, 교사가 교육과정을 분석 하는 현상을 세 가지로 논의하였다. 첫째, 교사가 분석하는 대상은 다양했다. 즉 교사는 교육과정 실행의 장에 존재하는 국가교육과정, 지역교육과정, 학교교육과정, 교실교육과정 등을 대상으로 교육과정을 분석하고 있었다. 둘째, 각 교육과정에서 교사가 분석하는 것은 각 교육과정에서 제시하는 기준과 내용이었다. 셋째, 교사가 교육과정을 분석하는 목적(이유)은 교사가 교육과정을 개발하기 위한 것이었다. This study was conducted through a Delphi study targeting a group of 12 experts to reveal the phenomenon that teachers analyze the curriculum. As a result of the study, First, in the first Delphi what and how to analyze when analyzing the curriculum, a total of 127 questions (69 what, 58 how) were obtained through open questionnaires. Second, in the second Delphi, the results of the first order were categorized into three areas, and a total of 62 items were obtained. Third, in the 3rd Delphi, 45 items were determined through the content validity (CVR), and the final 28 items were confirmed by considering the degree of agreement. Based on this result, three phenomena in which teachers analyze the curriculum were discussed. First, the subjects analyzed by teachers were diverse. In other words, the teacher was analyzing the curriculum targeting the national curriculum, regional curriculum, school curriculum, and classroom curriculum that exist in the field of curriculum execution. Second, what teachers analyzed in each curriculum were the standards and contents presented in each curriculum. Third, the purpose (reason) for the teacher to analyze the curriculum was for the teacher to develop the curriculum.

태양전지(太陽電池) 폐(廢) 모듈로부터 실리콘 및 강화(彈化)유리 회수(回收)에 관(關)한 연구(硏究)

강석민,유성열,이진아,부봉현,유호진,Kang, Suk-Min,Yoo, Sung-Yeol,Lee, Jin-A,Boo, Bong-Hyun,Ryu, Ho-Jin 한국자원리싸이클링학회 2011 資源 리싸이클링 Vol.20 No.2

본 연구에서는 다양한 방법들을 이용하여 태양전지 폐 모듈로부터 태양전지의 주요 구성요소인 실리콘과 강화유리를 회수하는 연구를 수행하였다. 강화유리는 유기용매를 사용하여 회수하였고, EVA수지는 열처리를 통하여 완전히 제거하였다. 실리콘은 계면 활성제를 첨가한 혼산용액을 이용하여 표면물질을 제거하고 회수하였다. 90%이상의 높은 실리콘 회수율을 얻었다. 본 연구에 의하여 얻어진 강화유리와 실리콘은 태양전지 모듈의 원료로 재활용되어 실리콘 공급부족 문제해결, 태양전지 제조원가 및 폐기물 처리비용 절감에 기여할 것으로 기대된다. We devised a procedure for the recovery of silicon and tempered glass from waste photovoltaic (PV) modules using optimized conditions. The tempered glass was recovered without any damage using organic solvents. The surface material is removed by applying an acid solution on the surface of the PV cell. Through our proposed method, we offer a much more efficient approach for recycling solar cells with a surfactant than the conventional method. This process, we obtained pure silicon with a yield of 90% by chemical treatment with the surfactant at room temperature for 18 min. The silicon yield was characterized using an inductively coupled plasma-atomic emission spectrometer.

연료전지(燃料電池) 막전극접합체(膜電極接合體)의 막분리(膜分離) 및 백금(白金) 회수(回收)에 관(關)한 연구(硏究)

이진아,강석민,유성열,강홍윤,류호진,Lee, Jin-A,Kang, Suk-Min,Yoo, Sung-Yeol,Kang, Hong-Yoon,Ryu, Ho-Jin 한국자원리싸이클링학회 2011 資源 리싸이클링 Vol.20 No.4

Present paper reports a new method to separate the electrolyte membranes and carbon paper without using ultrasonic waves and stirring. In this method, these were separated from fuel cell membrane-electrode assembly(MEA) using the distilled water, butanol and surfactant by dipping method without the dispersion of catalyst particles. Separated carbon paper catalysts and fuel cell Pt/C catalysts were heated in aqua regia at $80{\sim}85^{\circ}C$ and added to precipitant. After calcination, Pt metal was recovered which might be used in fabricating new fuel cells. 본 논문에서는 초음파나 교반 없이 전해질막과 확산층을 분리하기위한 새로운 방법에 대해 연구하였다. 증류수, 부탄올, 계면활성제를 이용하여 연료전지 막전극접합체의 전해질막과 확산층을 침지법으로 촉매입자의 분산 없이 분리하였다. 또한 분리된 확산층의 촉매와 연료전지 Pt/C 촉매를 왕수에서 $80{\sim}85^{\circ}C$로 가열하여 촉매입자를 녹여 침전제를 첨가하였다. 이후 소성하여 백긍 금속을 회수하였고 이는 새로운 연료전지용 전극촉매를 만드는데 사용될 것이다.

반응표면 분석법을 이용한 천연마섬유보강 순환굵은골재 콘크리트의 성능 평가

전지홍,김황희,김춘수,유성열,박찬기,Jeon, Ji Hong,Kim, Hwang Hee,Kim, Chun Soo,Yoo, Sung Yeol,Park, Chan Gi 한국농공학회 2014 한국농공학회논문집 Vol.56 No.4

In this study, evaluated ware the strength and durability of the vegetated water purification channel concrete to which recycled aggregates, hawang-toh and jute were applied. Box-Behnken method of response surface analysis in statistics was applied to the experimental design. Experimental variables are as follows, recycled coarse aggregates, hawang-toh, blast-furnace slag and jute fiber. In the experiment, conducted were the tests of compressive strength, chloride ion penetration, abrasion resistance and impact resistance the replacement rate effects of the recycled aggregates, blast-furnace slag and hwang-toh on the performance of vegetated water purification channel concrete were analyzed by using the response surface analysis method on the basis of the experimental results. In addition, an optimum mixing ratio of vegetated water purification channel concrete was determined by using the experimental results. The optimum mixing ratio was determined to be in 10.0% recycled coarse aggregates, 60.0% blast-furnace slag, 10.1% hwang-toh and 0.16% jute fiber. The compressive strength, chloride ion penetration, abrasion rate, and impact number of fracture test results of the optimum mixing ratio were 24.1 MPa, 999 coulombs, 10.30 g/mm3, and 20 number, respectively.

분산형 빗물관리시설 적용을 위한 수질정화기능 여재 성능 평가

박찬기,김춘수,김황희,유성열,전지홍,Park, Chan Gi,Kim, Chun Soo,Kim, Hwang Hee,Yoo, Sung-Yeol,Jeon, Ji Hong 한국농공학회 2014 한국농공학회논문집 Vol.56 No.6

In this study, the water quality purification of new medias which were NPS media, hyugato, mineral stone, charcoal for applying soil media of Integrated Management Practices (IMPs) of Low Impact Development (LID) were evaluated. The influent concentrations of COD, T-N, and T-P were 117.8 mg/L, 17.1 mg/L, and 2.062 mg/L, respectively. The infiltration capacities of NPS media, hyugoto, mineral stone, charcoal, and gravel were $7.1{\times}10m/s$, $7.3{\times}10^{-5}m/s$, $7.9{\times}10^{-5}m/s$, $6.0{\times}10^{-5}m/s$, respectively. All media meet criteria of infiltration capacity as surface soil layer at IMPs which is over $1.0{\times}10^{-5}m/s$. Maximum removal rates of COD, T-N, and T-P occurred at Charcoal with 98 % of COD removal rate, NPS with 78 % of T-N removal rate, and hyugato with 75 % fo T-P removal rate, respectively. For more high removal efficiency of all water quality item, the mixed media which is 4.5(NPS media): 1(charcoal) : 4.5 (hyugato) as volume ratio was evaluated. The infiltration capacity of mixed media was $7.9{\times}10^{-5}m/s$ and met the criteria of infiltration as surface soil layer. The water quality removal efficiencies of mixed media were very high with showing 70 % for COD, 85 % for T-N, and 71 % for T-P. The mixed media could purify the water quality of surface runoff and was recommended to used at the LID site of ground water quality problem.