Study on Crystallization Kinetics and Thermal Properties of PCF-co-EF/PLA Blends

Han Eol Kim(김한얼),Byeong Uk Nam(김한얼) 한국고분자학회 2018 폴리머 Vol.42 No.4

본 연구는 poly(cyclohexylenedimethylene furandicarboxylate-co-ethylene furandicarboxylate)(PCF-co-EF)와 poly(lactic acid)(PLA)를 블렌드하여 furan 기반의 바이오 복합재 개발을 목표로 하였다. PLA는 순수 PLA(4032D)와 첨가제가 마스터 배치된 PLA(3801X)를 사용하였다. FE-SEM을 통해 서브 마이크론의 구형 도메인 입자들이 복합재 내에 분산되어 있는 것을 통해 상용성을 확인하였고, 열적 물성 분석 및 비등온 결정화 거동 분석을 통해 PLA가 복합재의 결정화 속도를 가속시킨다는 것을 확인하였다. 또한 DMA를 이용한 동적 물성 측정을 통해 복합재의 상용성 및 연성의 향상을 확인하였다. The goal of this study is to develop furan based bio-composites by blending poly(cyclohexylenedimethylene furandicarboxylate-co-ethylene furandicarboxylate) (PCF-co-EF) with poly(lactic acid) (PLA). Two types of PLA are used in this study and one is neat PLA mostly consisting of L-lactide (4032D) and the other is master batched PLA with various additives (3801X). The FE-SEM results showed sub-micron dispersion of the spherical domains in the blends, which indicates compatibility between PCF-co-EF and PLA. The thermal properties and non-isothermal crystallization kinetics shows that the PLA accelerates the rate of crystallization. Dynamic mechanical analysis showed compatibility of the blends and the improvement of ductility of the composites.

Synthesis of bio-based polyol using Soybean oil

Han-Eol KIM,Byeong-Uk NAM 한국고분자학회 2016 한국고분자학회 학술대회 연구논문 초록집 Vol.41 No.2

Analysis of Ball Landing Locations in Grand Slam Matches of Tennis

( Han Eol Kim ),( Koo In Jung ),( Jeon Gyu Ko ) 한국체육학회 2015 국제스포츠과학 학술대회 Vol.2015 No.1

Purpose: This study has the objective in assessing the tactical ball locations where the ball landed in the structural characteristics of the professional tennis. In order to analyze the tactical patterns, the ball locations were collected through the whole match and compared 1st round match with semi-final match. Method: Matches were the first round and the semi-final of Australian Open, both played in 2012 respectively. The method used in the study is the convex hull algorithm which is computing the convex hull of a finite set of points in computation of geometry. The reason that this method was used is to clearly analyze a tactical playing area of ball locations of top ranked tennis players and different varying ball locations of professional tennis player. Result: For the tactics analysis both the court location where the ball landed and the area of shots in each section were considered. However if the shot was a serve or out then the shot was not analyzed, only during rallies. We thought that tactics might change when playing against left or right handed players and when playing in the first round and the semi-final. First, in the first round, both winner and loser showed the highest frequency in section 2 (x: 205.74~411.48cm, y: 891.54~1188.72cm) which was 16.03% of total shots and 15.86% respectively. The second highest frequency for both players were the section 4 (x: 205.7~ 411.48cm, y: 594.36~891.54cm) for winner and the section 12 (x: 0~205.74cm, y: 594.36~891.54cm) for the loser. The occupied area of ball locations for winner in section 2 was 3.763m2 and 3.598m2 for loser in the first round, 13.82% and 12.68% respectively. Second, in the semi-final, winner showed the highest frequency in section 4 as 19.39% of total shots and loser showed the highest frequency in section 3 (x: -205.74~-411.48cm, y: 594.36~891.54cm) as 20.25%. The occupied area of ball locations for winner in section 4 was 5.197m2 and for loser in section 3 as 5.245m2, 10.95% and 10.89% respectively. Conclusion: This study has provided a method for dividing the tennis court into 16 sections for calculating the occupied area of ball locations. There is a significant difference in frequency and percentage between the 1st round match and the semi-final match. However, there is no significant difference in the occupied area of ball locations. Winners tended to show a different strategy depending on the opponent`s performance level or right-handed or left-handed.

차단 주파수 가변형 HPF를 이용한 듀얼 3상 인버터의 스위치 개방 고장 검출 기법

김한얼(Han-Eol Kim),이기창(Ki-Chang Lee),김경엽(Kyung-yub Kim),박종원(Jong-won Park),황선환(Seon-Hwan Hwang) 한국조명·전기설비학회 2022 조명·전기설비학회논문지 Vol.36 No.11

4년제 대학교 및 2·3년제 전문대학 반려동물분야 교육과정 분석 및 비교 연구

한얼(Eol Han),김은지(Eun Ji Kim),김호진(Ho Jin Kim),조상문,정아현(A Hyun Jung),정훈(Hoon Chung) 반려동물연구학회 2019 Animalia Vol.1 No.1

과거 ‘애완동물’이라는 단어는 이제는 ‘반려동물’이라 부르면서 반려동물의 사회적 지위가 상승하였고 반려동물을 기르는 가구는 이미 1000만을 넘어섰다. 사회적으로 반려동물의 관심이 커지며 반려동물 분야 종사자들에게 더 많은 지식과 전문성을 요구하게 되었다. 본 연구에서는 현재 국내 반려동물 관련 교육과정이 존재하는 2,3년제 전문대학과 4년제 대학교를 파악하고 이들 대학의 전체 과목 대비 반려동물 관련 과목 비율과 편성된 과목의 종류도 조사하였다. 조사된 자료를 통하여 2,3년제 전문대학과 4년제 대학교 간 반려동물 분야의 교육과정 현황을 비교 분석하였다. 분석결과 2,3년제 전문대학 내 반려동물 관련 교육과정은 실습위주의 과목이 주로 편재되어있었으며 학과 내 반려동물 관련 과목 비중이 높았다. 반면 4년제 대학교의 경우, 포괄적이고 이론위주의 과목이 주로 편재되어 있었으며, 전 과목 대비 반려동물관련 과목 비율이 낮게 나와 2,3년제 전문대학의 교육과정과 비교하였을 때 차이점이 있었다. The social status of the companion animals, called now but ‘pet’ in the past, has risen and the number of households that have companion animals exceeded 10 million. The public becomes interested in companion animals steadily and then demands more knowledge and expertise from companion animal workers. In this study, we identified the colleges and universities that have curriculums for companion animal. Then we found the ratio of companion animal subject to all subjects and kinds of companion animal subjects. Based on the survey data, we compared and analyzed the current status of the companion animal curriculum between colleges and universities. As a results of the analysis, practice-oriented subjects were concentrated in curriculum in college. On the other hand, in the case of universities, comprehensive and theoretical-oriented subjects were organized mainly and low proportion of all subjects, in the department, then after all, there was differences when compared to the curriculum of colleges.

절연형 Inverse-SEPIC의 모델링 및 제어 특성

박한얼(Han-Eol Park),金銀錫(Eun-Seok Kim),金?石(Soo-Seok Kim),宋重鎬(Joong-Ho Song) 전력전자학회 2008 전력전자학회 논문지 Vol.13 No.1

수요대응형 기숙사시설을 위한 모듈러공법 적용 방안

김한얼 ( Kim Han Eol ),임형철 ( Lim Hyoung Chul ) 한국건축시공학회 2021 한국건축시공학회 학술발표대회 논문집 Vol.21 No.1

Currently, the school-age population continues to decline in Korea due to social factors. On the other hand, the dormitory facilities are constantly being built and renovated. There are many problems such as construction period and on-site waste when constructed with reinforced concrete structures, which are existing construction methods. Accordingly, dormitory facilities shall be constructed using appropriate construction methods. Therefore, in this study, we will collect and organize basic data on the use status and modular system of dormitory facilities and study efficient maintenance and management when modular construction method is applied to dormitory facilities with changing demand.

119 재난상황신고전화의 음성정보에서 나타난 신고자의 공간정보 표현 분석

김한얼(Han Eol Kim),장서정(Seo Jeong Jang),권규현(Gyu Hyun Kwon) 한국HCI학회 2016 한국HCI학회 학술대회 Vol.2016 No.1

건설공사 안전관리자 업무 분장 실태조사 연구

김한얼 ( Kim Han-eol ),안재홍 ( Ahn Jae-hong ),임형철 ( Lim Hyoung-chul ) 한국건축시공학회 2023 한국건축시공학회 학술발표대회 논문집 Vol.23 No.1

If the participants in construction site safety management perform their duties in accordance with the provisions of the Industrial Safety and Health Act, the burden on safety managers would be minimal. However, the lack of specific work guidelines for each participating entity and the greater responsibility of the safety and health general manager than the management supervisor have resulted in safety managers’ workload being increased due to the problem of management supervisors’ neglect of safety management. In this study, we conducted a survey of the safety manager’s duties and related documents during the construction project initiation, early stages, ongoing work, and disaster occurrence/investigation, and conducted interviews to improve and enhance the division of duties.

Fe-V Chloric/Sulfuric Mixed Acid 레독스흐름전지 전극의 활성화 온도에 따른 전기화학적 성능 고찰

이한얼 ( Han Eol Lee ),김대업 ( Dae Eop Kim ),김철중 ( Cheol Joong Kim ),김태근 ( Taekeun Kim ) 한국공업화학회 2020 공업화학 Vol.31 No.6

레독스흐름전지(redox flow battery, RFB)의 구성 부품 중 전극은 전해액의 확산층 역할을 함과 동시에 전자의 통로 역할을 담당하여 출력에 직접적인 영향을 미치는 주요 부품이다. 본 연구는 Fe²⁺/Fe³⁺와 V²⁺/V³⁺를 레독스 커플로 사용한 RFB 시스템에 chloric/sulfuric mixed acid 지지 전해액을 사용한 경우 전극 종류 및 활성화 정도에 따른 용량, 쿨롱 효율, 에너지 효율을 비교하여 최적의 전극 및 활성화 정도를 제시하였다. 실험에 사용된 5종의 탄소 전극을 사용한 단일셀 평가에서 모두 이론 용량에 근사한 값을 보여 신뢰성을 확보하였으며, 사용된 전극 중 GFD4EA는 상대적으로 우수한 에너지 효율 및 충방전 용량을 나타내었다. 활성화 온도에 따른 전기화학적 성능 고찰을 위하여 GFD4EA 전극을 공기분위기 하에서 400, 450, 500, 600 및 700 ℃에서 열처리하여 활성화하였다. 질량 변화, 주사전자현미경(SEM) 및 XPS 분석을 통하여 활성화 전 후의 물성 변화를 관찰하였으며, 각각의 온도에서 활성화된 전극을 적용한 RFB 단일셀 평가를 실시하여 전기화학적 성능을 비교하였다. Among the components of redox flow battery (RFB), the electrode serves as a diffusion layer of an electrolyte and a path for electrons and also is a major component that directly affects the RFB performance. In this paper, chloric/sulfuric mixed acidwas used as a supporting electrolyte in RFB system with Fe²⁺/Fe³⁺ and V²⁺/V³⁺ as redox couple. The optimum electrode and activation temperature were suggested by comparing the capacity, coulombic efficiency and energy efficiency according to the electrode type and activation temperature. In the RFB single cell evaluation using 5 types of carbon electrodes used in the experiments, all of them showed close to the theoretical capacity to retain the reliability of the evaluation results. GFD4EA showed relatively excellent energy efficiency and charge/discharge capacity. In order to investigate the electrochemical performance according to the activation temperature, GFD4EA electrode was activated by heat treatment at different temperatures of 400, 450, 500, 600 and 700 ℃ under an air atmosphere. Changes in physical properties before and after the activation were observed using electrode mass retention, scanning electron microscope (SEM), XPS analysis, and electrochemical performance was compared by conducting RFB single evaluation using electrodes activated at each temperature given above.