4-Vinyl-3-phenylsydnon의 중합반응 및 그 중합체의 물성에 관한 연구(I) ―4-Alkenylsydnone의 합성 및 그의 중합성에 관하여―

채희주,김영률,조성무,Chae, Hui-Ju,Kim, Yeong-Ryul,Jo, Seong-Mu 한국섬유공학회 1988 한국섬유공학회지 Vol.25 No.4

After metalation of 3-phenylsydnone by using n-BuLi or n-BuMgBr, 4-(2-hydroxyisopropyl)-3-phenylsydnone and 4-(1-hydroxy-1-ethyl)-3-phenylsydnone are obtained by addition reaction of acetone and acetaldehyde, respectively. The subsequent dehydration of each cabinol using P2O5 produces the corresponding alkenylsydnones. Polymerization reaction is carried out using this 4-vinyl-3-phenylsydnone; the reaction does not occur in the presence of radical initiator, on the other hand, the dimer is formed under cationic initiator, BF3-etherate and its structure is proposed. But the oligomer is obtained under the anionic polymerization condition.

투명한 PMMA 로 된 플라스틱 섬유의 광학적 성질

채희주,Hee-Ju Chae,Yasuhiro Koike 대한화학회 1989 대한화학회지 Vol.33 No.4

완전히 불순물을 제거한 투명한 polymethylmethacrylate(PMMA)의 prerod를 제조하여 연속 열연신하여 얻은 플라스틱 섬유의 연신온도($T_d$)에 따른 굴절율, 굴절율분포, 복굴절율 및 전송손실율을 측정하였다. $T_d$가 높을수록 다소 낮은 굴절율을 보였으나, 섬유의 중심에서 주변으로 감에 따른 굴절율분포는 오히려 낮은 $T_d$에서가 현저했고, 높은 $T_d$에서는 주변에서만 급격한 굴절율의 강하를 보였다. 또한 $T_d$가 220$^{\circ}C$ 미만에서는 복굴절을 ${\Delta}$n = $5{sim}6{\times}10^{-4}$을 보이고 그 보다 높은 온도의 $T_d$에서는 이러한 현상이 나타나지 않았다. Attenuation은 높은 $T_d$일수록 낮은 값을 보였다. The refractive index, refractive-index distribution, birefringence, and the attenuation of the plastic fiber prepared from the transparent PMMA prerod were measured in accordance with continuous heat drawing temperature($T_d$). The refractive indices were decreased with $T_d$ elevation but the refractive-index distribution from the center of fiber to periphery was higher at lower $T_d$. The steep decrease of gradient index was only at the periphery of higher $T_d$. Birefringence was observed only below $220^{\circ}C$ and ranged $5{\times}10^{-4}$ to $6{\times}10^{-4}$. No birefringence was observed above $220^{\circ}C$. An elevation of $T_d$ brought about a monotonous decrease in the attenuation of the fiber.

실내 사람 위치 추적 기반 LSTM 모델을 이용한 고객 혼잡 예측 연구

채희주,곽경헌,이다연,김은경 한국시뮬레이션학회 2023 한국시뮬레이션학회 논문지 Vol.32 No.3

본 연구는 실내 상업적 공간, 특히 카페에서 보안 카메라를 이용해 방문자 수와 위치를 실시간으로 파악하고, 이를 통해 사용 가능한 좌석 정보와 혼잡도 예측을 제공하는 시스템의 개발을 목표로 한다. 우리는 실시간 객체 탐지 및 추적 알고리즘인 YOLO를 활용하여 방문자 수와 위치를 실시간으로 파악하며, 이 정보를 카페 실내 지도에 업데이트하여 카페 방문자가 사용 가능한 좌석을 확인할 수 있도록 한다. 또한, 우리는 vanishing gradient문제를 해결한 장단기 메모리(Long Short Term Memory, LSTM)와 시간적인 관계를 가지는 데이터를 처리하는데 유용한 시퀀스-투-시퀀스(Sequence-to-Sequence, Seq2Seq)기법을 활용해 다양한 시간 간격에 따른 방문자 수와 움직임 패턴을 학습하고, 이를 바탕으로 카페의 혼잡도를 실시간으로 예측하는 시스템을 개발하였다. 이 시스템은 카페의 관리자와 이용자 모두에게 예상 혼잡도를 제공함으로써, 카페의 운영 효율성을 향상시키고, 고객 만족도를 높일 수 있다. 본 연구에서는 보안 카메라를 활용한 실내 위치 추적 기술의 효용성을 입증하며, 상업적 공간에서의 활용 가능성과 더불어 미래 연구 방향을 제시한다. In this detailed and comprehensive study, our primary focus has been placed on accurately gauging the number of visitors and their real-time locations in commercial spaces. Particularly, in a real cafe, using security cameras, we have developed a system that can offer live updates on available seating and predict future congestion levels. By employing YOLO, a real-time object detection and tracking algorithm, the number of visitors and their respective locations in real-time are also monitored. This information is then used to update a cafe’s indoor map, thereby enabling users to easily identify available seating. Moreover, we developed a model that predicts the congestion of a cafe in real time. The sophisticated model, designed to learn visitor count and movement patterns over diverse time intervals, is based on Long Short Term Memory (LSTM) to address the vanishing gradient problem and Sequence-to-Sequence (Seq2Seq) for processing data with temporal relationships. This innovative system has the potential to significantly improve cafe management efficiency and customer satisfaction by delivering reliable predictions of cafe congestion to all users. Our groundbreaking research not only demonstrates the effectiveness and utility of indoor location tracking technology implemented through security cameras but also proposes potential applications in other commercial spaces.

라디칼 중합반응에 미치는 산화 : 환원 개시제의 영향

蔡熙珠,柳鶴洙 연세대학교 자연과학연구소 1980 學術論文集 Vol.6 No.-

최근 Palit 등에 의하여 과망간산칼륨-옥살산으로 된 산화-환원 개시제에 의하여 개시되어지는 용액중합반응의 메카니즘과 그 반응속도론적 연구가 이루어져 왔다. 본 연구에서는 과망간산칼륨과 산화조건에서 비교적 카르복실기가 떨어져 나오기 쉬운 타르타르산, 젖산, 시트르산과 말레산과의 산화-환원 개시반응을 아크릴 아미드 용액 중합반응에서 반응속도론적 연구를 하였다. 촉매와 activator인 산의 농도가 중합반응에 미치는 의존도를 보기 위해서 각각의 농도를 변화시켜가며 일정한 시간간격으로 중합도를 측정하고 또한 위의 산들의 개시제로서의 역량을 그 구조와 연관시켜 해석코자 한다. Recent papers have reported the studies on the kinetics and mechanism in aqueous polymerization initiated by Potassium-Permanganate-Oxalic acid as Redox Initiator by Palit and al. In this study, Potassium-Permanganate with Tartaric acid, Lactic acid, Citric acid and Malic acid in which decarboxylation occurs relatively easily under oxidation conditions accomplished a fine initial reaction in aqueous acrylamide polymerization. After polymers abtained were separated immediately by MeOH and washed with MeOH, dried in vacuum at 50℃ and weighed, the yield percentage was calculated. To certify the dependence of polymerization reaction, A series of experiments were practised under various concentrations of respective catalyst and activator at regular reaction time intervals. By resultant data, the polymerization reaction was much favored not by activator concentration but by catalyst concentration. That is because Mn^+3-active carboxylate directly effected on polymerization degree. Forethemore, in interpretation for activity as initiator of the above acids, the structual study was concerned. When exists electron attracting group attached at α-carbon, the reaction is activated.

열분해 기체크로마토그래피를 이용한 PVA-polyvinyltrifluoroacetate 공중합체중의 trifluoroacetyl 기의 정량

채희주,조성무,유학수,Chae, Hee-Ju,Jo, Seong-Mu,Lyu, Hark-Soo,Nakajima, Toshinari 대한화학회 1987 대한화학회지 Vol.31 No.3

열분해 기체크로마토그래피법을 이용하여 C-F 결합을 깨지 않고 PVA-PVFAc 공중합체중의 trifluoroacetyl기의 양을 정량하여, 공중합체내의 단량체 VFAc의 조성몰분율을 구하였다. GC-pyrogram에서의 trifluoroacetyl compds의 봉우리 면적은 공중합체 시료 3mg이내에서 시료무게와 직선관계를 갖는다. 서로 다른 trifuoroacetyl 치환도를 갖는 공중합체의 gas chromatogram으로부터 계산된 플루오르의 양은 이온전극법을 이용한 플루오르원소 분석치와 잘 일치한다. The composite mole fraction of monomers in PVA-PVFAc copolymer could be calculated from the analysis of trifluoroacetyl group by the pyrolysis gas chromatography without breaking of C-F bonds in polymer. A linearity between trifluoroacetyl peak areas in pyrogram and sample weights was obtained within the range below 3mg. The data of trifluoroacetyl contents derived from gas chromatogram of copolymers with various D.S. were in good agreement with results by the Specific Ionmeter.

Cyclic triphosphazene의 Vinyl 유도체의 합성과 셀룰로오스에의 그라프트 중합반응에 관한 연구

채희주 연세대학교 대학원 1985 延世論叢 Vol.21 No.3

Abstract Penta-2,3-dibromopropoxyallyloxycyclotriphosphafene, N3P3OCH2CH=CH2(OCH2CHBrCH2Br)5 was synthesized and identified by IR, mass and elemental analysis of C, H, N and halogens. This vinyl monomer can be grafted on cellulose initiated by CeIV ions without opening its aromatic phosphazene ring. After extraction of homopolymer, thermal behavior of grafted cellulose was studied and compared with that of pure cellulose by TGA and DSC analysis. Grafted cellulose showed two typical double peaks at 240 and 274℃ in DSC and lowered the decomposition temperature and increased the amount of char. This shows that decomposition mechanism of grafted cellulose is different from that of pure cellulose, which then lead to subsequent increase in flame retardant property and consistent with oxygen index of treated cotten.

소통을 위한 영화의 형식적 표현 연구 -영화 <증인>을 중심으로-

채희주,민경원 한국영상제작기술학회 2020 영상기술연구 Vol.- No.32

Film is a form of art. The film uses a formal method to tell the story dramatic. The director uses the formal method of film to communicate with the audience. This study examined how formal techniques are implemented in the movie <Innocent witness>. In this study, three formal research models are applied. First, grasp the formal structure of how the subject communicates and connects with Others through the Actantial model of semiotics, Greimas. Second, look at how the formal aspect is used in film works through mise-en-scene. Third, let’s look at how to communicate through Brecht’s theory of ‘Distancing'. ‘Distancing’ is used as a concept of ‘conscious awareness’ in Cinema therapy. The purpose of this article is to examine how the formal expression of distancing is related to Cinema therapy. This study aims to examine how the movie <Innocent witness> expresses the formal sign of the movie on the topic of communication. 영화는 형식의 예술이라고 한다. 영화는 형식적인 방법을 이용해서 이야기를 극적(Dramtic)으로 전달한다. 감독은 영화의 형식적인 방법을 활용하여 관객들과 소통한다. 본 연구에서는 영화 <증인>에서 형식적인 기술들이 어떻게 구현되는지 살펴보았다. 본 연구에서는 세 가지 형식적인 연구 모델을 적용한다. 첫째, 기호학자인 그레마스의 행위소 모델을 통해서 주체가 어떻게 세상과 소통하고 관계 맺는지 그 형식구조를 파악한다. 둘째, 미장센을 통해 형식적 측면이 어떻게 영화작품에 활용되는지 살펴본다. 셋째, 브레히트의 ‘거리 두기’이론을 통해 어떻게 소통하는지 살펴본다. ‘거리 두기’는 영화치료에서는 ‘의식적 자각’의 개념으로 활용하고 있다. 거리 두기의 형식적 표현이 영화치료와 어떤 연관성이 있는지 다루고자 한다. 본 연구에서는 영화 <증인>이 소통이라는 주제로 영화의 형식적 기호가 어떻게 표현되는지 살펴보고자 한다.

Polyvinylalcohol-graft-poly (2,2,2-trifluoroethyl methacrylate) Copolymer 의 합성과 표면 특성에 관한 연구

채희주,이석준,고석원,Chae Hee Ju,Lee Seok Joon,Ko Sohk Won 대한화학회 1992 대한화학회지 Vol.36 No.1

$Ce^{4+}$ ion을 개시제로 사용하여 폴리비닐알코올에 2,2,2-trifluoroethyl methacrylate를 그라프트중합 반응시켜 새로은 PVA/perfluoroalkylmethacrylate 그라프트 공중합체들을 합성하였다. 수소 결합능이 큰 폴리비닐알코올에 여러 가지 그라프트율을 갖는 공중합체의 표면 자유에너지를 이 고체 표면들과 여러가지 액체와의 접촉각을 측정하여 구하였다. Perfluoroalkyl group이 그라프팅이 커짐에 따라 고체의 표면 자유에너지는 감소하며, 그 고체들은 극성 부분에 의해 기여되는 힘이 크므로 극성 고체의 분자 특성을 고려한 식으로부터 ${\gamma}_{si}$을 구하여 임계 표면 에너지 ${\gamma}_c$를 계산하였다. New graft copolymers were synthesized by grafting 2,2,2-trifluoroethylmethacrylate on polyvinylalcohol in aqueous solution with $Ce^{4+}$ ions as initiator. Surface free energies of copolymers having various grafting percentages were studied by measurements of contact angles for various liquids. As the grafting of perfluoroalkyl group increases, surface free energy of solid decreases. Estimation of critical surface free energy should be accounted for molecular properties because the polar force components of these solids are relatively great. ${\gamma}_c$ was calculated from the plot of ${\gamma}_{si}$ vs ${\Phi}_{sl}$.

패션마케팅 분야의 연구동향 분석: 2010~2022년 까지 국내학술지를 중심으로

채희주,신장희,이영주 학습자중심교과교육학회 2023 학습자중심교과교육연구 Vol.23 No.24

Objectives This study aims to identify changes in fashion marketing research and suggest a direction to move forward by analyzing the current status of fashion marketing research by academic journal overall. Methods This study focuses on research related to fashion marketing among 6,452 papers published in a total of seven academic journals in the field of textiles and clothing from 2010 to 2022. The contents of study are analyzed based on the ratio published in related papers by textiles and clothing related academic journals, trends and ratios by academic journals according to research topics, comparison of research methodologies, and gender ratio of the study subjects. Results The important points in this study are as follows. First, current fashion marketing related research is expanding its scope to various journals dealing with convergence studies as well as textile and clothing related journals. In addition, since various studies are being conducted in the category of fashion marketing, it seems necessary to consider to what extent fashion marketing should be categorized in terms of the perspective and area of research. Conclusions This study analyzed the current status of fashion marketing research by academic journal, resulting in meaningful findings that suggest the direction not only of future research but also of the fashion industry. There is a limit to expanding and interpreting the research results of an integrated analysis of seven academic journals to the entire research of marketing studies. There have been no studies that have conducted an integrated analysis of a number of journals with regard to fashion marketing topics; in this respect, this study is very meaningful. Fashion marketing is a latecomer among textiles and clothing, and its history is shorter than other fields. However, as shown in this study, the pace of academic change is becoming more mature. Therefore, future oriented in-depth fashion marketing research focusing on the current fashion industry structure is continuously needed.

플라스틱 광학섬유

채희주 한국섬유공학회 1986 한국섬유공학회지 Vol.23 No.5