유리섬유강화 복합절연재료의 열화특성에 관한 연구

이규철,유근민,김경석,박홍태 울산대학교 1996 공학연구논문집 Vol.27 No.2

본 연구에서는 주위 환경 열화에 따른 복합절연재료의 절연특성과 수명을 향상시키기 위해 고온에서 흡습량을 변화시켰을 때와 탈습량을 변화시켰을 때 흡십시료와 탈습시료의 전기적 특성 및 기계적 특성을 조사하였다. 유리섬유 각층의 흡습상수는 각각 1층에서 0.0117, 2층에서 0.0123, 3층에서 0.0152를 나타냈다. 전기적 특성 및 기계적 특성은 복합재료의 흡습에 따라 크게 떨어졌다. 70℃에서 습기가 완전히 건조되어도 흡습전의 전기적 및 기계적 특성을 얻기가 어려운 것으로 나타났다. 수분에 의해 발생한 복합절연재료내에 존재하는 많은 결함들은 에폭시 메트릭스와 필라사이에 존재하였다. The electrical and mechanical properties of moisture absorbed and moisture desorbed specimens were investigated to improve the insulating characteristics and the reliability of composite materials against environment aging. Moisture absorption constants with the layers of glass fiber showed 0.0117 in 1 layer, 0,0123 in 2 layer and 0.0152 in 3 layer, respectively. Although moisture was removed at 70℃, it was impossible to obtain the initial electrical and mechanical properties. Many defects induced by moisture were observed at the interface between epoxy matrix and filler in composite materials.

Production of the Rare Ginsenoside Rh2-MIX (20(S)-Rh2, 20(R)-Rh2, Rk2, and Rh3) by Enzymatic Conversion Combined with Acid Treatment and Evaluation of Its Anti-Cancer Activity

( Bong-kyu Song ),( Kyeng Min Kim ),( Kang-duk Choi ),( Wan-taek Im ) 한국미생물생명공학회(구 한국산업미생물학회) 2017 Journal of microbiology and biotechnology Vol.27 No.7

The ginsenoside Rh2 has strong anti-cancer, anti-inflammatory, and anti-diabetic effects. However, the application of ginsenoside Rh2 is restricted because of the small amounts found in Korean white and red ginsengs. To enhance the production of ginsenoside Rh2-MIX (comprising 20(S)-Rh2, 20(R)-Rh2, Rk2, and Rh3 as a 10-g unit) with high specificity, yield, and purity, a new combination of enzymatic conversion using the commercial enzyme Viscozyme L followed by acid treatment was developed. Viscozyme L treatment at pH 5.0 and 50°C was used initially to transform the major ginsenosides Rb1, Rb2, Rc, and Rd into ginsenoside F2, followed by acid-heat treatment using citric acid 2% (w/v) at pH 2.0 and 121°C for 15 min. Scale-up production in a 10-L jar fermenter, using 60 g of the protopanaxadiol-type ginsenoside mixture from ginseng roots, produced 24 g of ginsenoside Rh2-MIX. Using 2 g of Rh2-MIX, 131 mg of 20(S)-Rh2, 58 mg of 20(R)-Rh2, 47 mg of Rk2, and 26 mg of Rh3 were obtained at over 98% chromatographic purity. Then, the anti-cancer effect of the four purified ginsenosides was investigated on B16F10, MDA-MB-231, and HuH-7 cell lines. As a result, these four rare ginsenosides markedly inhibited the growth of the cancer cell lines. These results suggested that rare ginsenoside Rh2-MIX could be exploited to prepare an anti-cancer supplement in the functional food and pharmaceutical industries.

A chemically regenerative redox fuel cell using (2,2,6,6-tetramethylpiperidin-1-yl)oxyl redox reaction in acid medium

Han, Sang-Beom,Kwak, Da-Hee,Park, Hyun Suk,Park, Jin-Young,Ma, Kyeng-Bae,Won, Ji-Eun,Kim, Do-Hyoung,Kim, Min-Cheol,Park, Kyung-Won Elsevier 2018 Journal of Power Sources Vol.393 No.-

<P><B>Abstract</B></P> <P>(2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) with no free radical and non-volatile characteristic can be utilized as a liquid catalyst instead of O<SUB>2</SUB> at the cathode in a chemical regenerative redox fuel cell with H<SUB>2</SUB> as a fuel at the anode. In this study, the electrochemical properties and performance of TEMPO dissolved in sulfuric acid solution are investigated using half and unit cells. In the half-cell, TEMPO shows an activation energy of 1.27 kcal mol<SUP>−1</SUP> K<SUP>−1</SUP> for the reduction. A chemical regenerative redox fuel cell (CRRFC) using TEMPO as the liquid catalyst exhibits an open circuit voltage of 0.7 V and a maximum power density of 90 mW cm<SUP>−2</SUP> at 30 °C with a low activation loss. The regeneration cycling test of the CRRFC is performed at a constant voltage of 0.4 V under a flow rate of the oxygen-bubbled TEMPO solution. The performance of the CRRFC deteriorates, i.e., a power density of zero measured at >200 min. Thus, a highly efficient regeneration system needs to be developed for a high-performance CRRFC using TEMPO used as a liquid-type oxidant. Furthermore, stable liquid oxidants with relatively high standard reduction potentials can be proposed through various organic compounds.</P> <P><B>Highlights</B></P> <P> <UL> <LI> CRRFC was proposed using TEMPO instead of O<SUB>2</SUB> at the cathode. </LI> <LI> TEMPO showed fairly fast transport and low activation energy for the reduction. </LI> <LI> CRRFC exhibited an open circuit voltage of ∼0.7 V at 30 °C. </LI> <LI> CRRFC exhibited a maximum power density of ∼90 mW cm<SUP>−2</SUP> at 30 °C. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

흑백색의 의미상징

한경민(Kyeng Min Han) 한국외국어대학교 동유럽발칸연구소 2024 동유럽발칸연구 Vol.48 No.1

이 논문은 한국과 헝가리 민요 텍스트에 나타난 흑백색의 의미상징에 관한 연구이다. 민요에 사용된 흑백색이 원형에서 출발하여 어떤 다양한 확장의미로 변화하는지에 대하여 고찰하였다. 즉 흑백색의 개념적 의미에서 출발하여 주제적, 내포적, 사회적, 정서적, 반영적, 연어적 의미로 확산되어 가는 용례를 찾아, 색채어가 표현하는 다양한 의미상징을 분류하였다. 분류의 방식은 색채의 의미가 개인이나 사회에 긍정적인 방향-부정적 방향인가에 따라 긍정적-부정적 의미상징으로 나누어 각각에 속하는 확장의미의 용례에 따라 분류하였다. 두 나라 민요에 사용된 흑백색이 공통적인 긍정적-부정적 의미를 가지고 있는지, 혹은 한 민족에게만 특정한 의미상징이 나타난다면, 그 이유가 무엇인지 찾아보고자 했다. 연구의 직접적인 목표는 색채가 가지고 있는 보편적이고 일반적 의미상징이 두 나라의 민요에서 공통적인 혹은 개별적이고 독자적인 의미상징을 가지는가 살펴보는 것이다. 연구 결과 흑백색의 원형은 두 민족에게 공통적이지만, 파생의미는 공통점만큼 차이점도 분명했다. 그 배경에는 두 민족의 종교, 역사, 생활환경과 같은 문화 환경적 요인의 영향임을 유추할 수 있다. This paper is a study on the meaning symbols of black and white in Korean and Hungarian folk song texts. Starting from the original form of black and white with basic meaning in folksongs, I analyzed the symbolism that contains various expanded meanings. In other words, starting from the conceptual meaning of black and white, we looked for usage cases that spread to thematic, connotative, social, emotional, reflective, and collocational meanings, and classified the various semantic symbols expressed by color words. The classification method was divided into positive and negative meaning symbols depending on whether the color's meaning was positive or negative for the individual or society, and the expanded meaning belonging to each was presented and classified. I wanted to find out whether the black and white colors used in the folk songs of the two countries have common positive and negative meanings, and if specific meaning symbols appear for one people, what the reason is. The direct goal of the study was to understand the universal and general meaning symbols of color, but behind the scenes, it was expected that each nation would have individual and unique meaning symbols. As a result of the study, the original black and white colors were common to both ethnic groups, but the derived meanings had both similarities and differences. It can be inferred that cultural and environmental factors such as the religion, history, and living environment of the two peoples may have had an influence in the background.

헝가리 대평원의 긍정적 이미지 -페퇴피 샨도르의 지역문학 작품 중심으로

한경민 ( Kyeng Min Han ) 세계문학비교학회 ( 구 한국세계문학비교학회 ) 2015 世界文學比較硏究 Vol.53 No.-

헝가리 대평원을 소재로 하여, 지역문학의 새로운 경지를 연 페퇴피의 작품은 대평원 지역이 단순한 황무지가 아니라 시인의 체험과 상상력이 결합된 특별한 장소로서 숨겨진 의미와 가치를 지니고 있음을 드러낸다. 기존의 고정화된 부정적 이미지에서 벗어나 생명과 자유라는 긍정적 이미지를 제시하기 위해 페퇴피는 대평원에 서식하는 여러 생물과 특별한 자연현상을 세밀하게 묘사하였다. 또한 대평원에 사는 사람들의 일상과 자연 재해에 맞서는 사람들의 행동을 통해 대평원이 지닌 새로운 의미와 가치를 제시하면서 기존 패러다임에서 벗어나려는 시도를 하고 있다. 33) 이런 시도의 기본적인 토대는 대평원이 헝가리 조상들이 터를 잡고, 자유를 얻기 위해 전투를 치룬 역사적인 땅이며, 그 결과 완전한 자유와 해방을 가져다 준 땅이었기 때문이라고 주장한다. 대평원의 무한한 광야에서 모든 사람이 느끼는 자유와 해방의 이미지는 이제 생명과 자유를 배태한 헝가리 인의 고향, 헝가리 인의 조국이라는 이미지로 확장된다. 여기에서 당시의 정치적 상황과 연결 지어 정치시로 해석하는 연구자들에게는 후기 혁명시로 이어지는초기 작품으로 인정받기도 한다. 1830년대의 낭만주의 운동에서 지향한 원시 그대로의 자연과 대평원의 이미지는 완벽하게 부합했고, 산간 지역과 대평원 지역 간의 논쟁을 통해서 대평원이 지닌 특징을 널리 알릴수 있는 분위기를 조성해주었다. 이런 분위기에서 배태된 페퇴피의 지역문학 작품은 대평원에서 즉 헝가리의 고향이자 조국에서 느끼는 완전한 자유라는 긍정적인 이미지를 획득하게해 주었다. 또한 대평원에 서식하는 생물, 특별한 자연현상과 인간의 삶을 소재로 다루면서 대평원을 생명과 삶이 가득한 지역임을 널리 알려주었다. 그의 지역문학 작품은 이후 다른 문학가들만이 아니라 화가와 조각가에까지 영향을 미쳐, 대평원이 간직하고 있는 긍정적인 이미지가 예술화하도록 영향을 주게 된다. Petofi’s works blazed a trail of regional literature by revealing the meaning and value of the Great Hungarian Plain as a subject matter; the plain is no longer a mere wasteland, but is a special place combining the poet’s experience and imagination. In order to break away from the traditional negative image of the Great Hungarian Plain and illustrate a positive image of vitality and freedom, Petofi depicted various creatures and natural phenomena of the Great Hungarian Plain in great detail. Also, he tried to be free from a traditional paradigm and present new meaning and value of the Plain by introducing inhabitants of the Plain, their daily lives, and their struggles against the natural phenomena. Petofi’s efforts are founded in the notion of the land’s freedom and liberation; the Hungarian forefathers located themselves in the Plain, and underwent battles for freedom. Such image of freedom and liberation everyone shares upon the infinite Plain now extends to a national image of Hungary from which freedom and liberation germinated. To researchers regarding this image as part of a political history in relation to political milieu, Petofi’s works are acknowledged as the early versions of the later revolutionary poems. 1830s’ Romanticist pursue of pristine nature made a perfect accordance with the image of the Plain. At the same time, a debate on the fields of the mountains and the plains made popularization of the plains’ image possible. In these circumstances, Petofi’s regional literature associated the Plain with ultimate freedom shared in Hungary as a nation and homeland. The positive image of the Great Hungarian Plain became a new paradigm influencing not only literature but also art such as painting and sculpture.

3차원 전자계-열전달 연성 해석을 통한 단로기 온도상승 현상 연구

강민철(Min Cheol Kang),이승관(Seung-Kwan Lee),정경식(Kyeng-Sik Jeong),이영민(Young-Min Lee),김경회(Kyong-Heo Kim) 대한전기학회 2017 대한전기학회 학술대회 논문집 Vol.2017 No.7

헝가리 영화 교수법 : 문학 강의 대안으로서의 가능성 제고

한경민(Kyeng Min Han) 한국외국어대학교 동유럽발칸연구소 2021 동유럽발칸연구 Vol.45 No.1

인문학 교육의 교재가 도서에서 영상물로 변화하는 것은 학습자들이 영상물과 함께 자라고 성숙한 영상세대라는 점과 연결된다. 대학의 학습자는 영상물에서 다양한 정보를 빠르게 얻고 있기 때문에, 문학 강의의 교재를 영상물 – 영화로 대치할 경우에도 외국어 습득과 외국 문화의 수용이라는 외국어학과 전공강의의 목적을 이룰 수 있는지를 확인하고자 2017년 <헝가리 예술과 문화코드> 강의를 신설하였다. 처음에는 문학작품을 영화화한 작품 위주로 강의하였지만, 점차 영화 자체가 학습교재가 될 수 있으며 학습자 주도의 교육적 방법을 접목할 경우 다양하고 창조적인 시각과 아이디어가 나타남을 확인하였다. 이 논문은 4년간의 강의에서 시도한 교수 방법을 정리하여 헝가리어 – 특수어로 제작된 – 영화 교수법으로 완성한 것이다. 결론적으로 문학 교재를 대체하여 영화를 교재로 선택할 수 있다는 긍정적인 가능성을 도출하면서 영화 강의의 교수법을 강의 주차와, 수업 전후로 세분화하여 실시하게 되었다. 이 교수법은 ‘학습자들이 영화를 즐겁게 보면서 스스로 학습’하며, ‘영화에 등장한 인물과 사건을 통하여 자기 자신의 삶을 만나도록 한다’는 데 기본 목표를 두고 강의자 주도가 아닌 학습자 주도 방식으로 수업을 진행하여 도출한 결과를 기술하였다. The textbooks of human arts are changing from textbooks to videos, and are connected to the fact that today’s learners have grown with videos. As the learners in colleges get information massively and quickly through videos, it is possible to achieve the Foreign Language major courses’s purpose by replacing the current teaching materials with videos – films. Based on this expectation, I opened the hungarian film course in 2017. As times goes on, it became clear that film can be one of the best literary materials by itself and shows various points of view and original ideas combined with learner-centered teaching methods. This paper summarizes the didactics that were used in the past 4 year course that can be used for other lessons on foreign films. Films made with special foreign languages such as hungarian can be difficult to understand without subtitles for the learners due to their time spent on learning and obstacles in their learning circumstances. To solve this problems, following methods were used; summarizing files through video compilation and providing korean subtitles, having students watch films as groups before the lesson, and having each student to independently watch films at home before the lesson. In conclusion, I evaluate films’ educational possibility positively and arranged the didactics of film lessons in detail according to the semester and class time table. This aims to make the learner ‘watch the film happily and learn by himself.’ For this purpose, I choose the learner-centered teaching methods, instead of the lecture-centered methods.

Reduction-Sensitive, Robust Vesicles with a Non-covalently Modifiable Surface as a Multifunctional Drug-Delivery Platform

Park, Kyeng Min,Lee, Don-Wook,Sarkar, Bijay,Jung, Hyuntae,Kim, Jeeyeon,Ko, Young Ho,Lee, Kyung Eun,Jeon, Hyesung,Kim, Kimoon WILEY-VCH Verlag 2010 Small Vol.6 No.13

<P>The design and synthesis of a novel reduction-sensitive, robust, and biocompatible vesicle (SSCB[6]VC) are reported, which is self-assembled from an amphiphilic cucurbit[6]uril (CB[6]) derivative that contains disulfide bonds between hexaethylene glycol units and a CB[6] core. The remarkable features of SSCB[6]VC include: 1) facile, non-destructive, non-covalent, and modular surface modification using exceptionally strong host–guest chemistry; 2) high structural stability; 3) facile internalization into targeted cells by receptor-mediated endocytosis, and 4) efficient triggered release of entrapped drugs in a reducing environment such as cytoplasm. Furthermore, a significantly increased cytotoxicity of the anticancer drug doxorubicin to cancer cells is demonstrated using doxorubicin-loaded SSCB[6]VC, the surface of which is decorated with functional moieties such as a folate–spermidine conjugate and fluorescein isothiocyanate–spermidine conjugate as targeting ligand and fluorescence imaging probe, respectively. SSCB[6]VC with such unique features can be used as a highly versatile multifunctional platform for targeted drug delivery, which may find useful applications in cancer therapy. This novel strategy based on supramolecular chemistry and the unique properties of CB[6] can be extended to design smart multifunctional materials for biomedical applications including gene delivery.</P> <B>Graphic Abstract</B> <P>Biocompatible vesicles based on cucurbit[6]uril (CB[6]) can undergo surface modification by host–guest chemistry, internalization into targeted cells by receptor-mediated endocytosis, and triggered release of entrapped drugs in cytoplasm. They serve as a highly versatile multifunctional platform for targeted drug delivery. <img src='wiley_img_2010/16136810-2010-6-13-SMLL201000293-content.gif' alt='wiley_img_2010/16136810-2010-6-13-SMLL201000293-content'> </P>

Dye-Cucurbit[n]uril Complexes as Sensor Elements for Reliable Pattern Recognition of Biogenic Polyamines

Park, Kyeng Min,Kim, Jeeyeon,Ko, Young Ho,Ahn, Youngjoo,Murray, James,Li, Meng,Shrinidhi, Annadka,Kim, Kimoon Chemical Society of Japan 2018 Bulletin of the Chemical Society of Japan Vol. No.

Guest-responsive, Non-proteolytic Harvest of a Cell-sheet using Controllable Host-guest Chemistry

Park, Kyeng Min,Shrinidhi, Annadka,Murray, James,Kim, Kimoon Wiley (John WileySons) 2018 Israel journal of chemistry Vol.58 No.3