Interfacial Characteristics of Epoxy Composites Filled with γ-APS Treated Natural Zeolite

이재영,이상근,김상욱,Lee, Jae-Young,Lee, Sang-Keun,Kim, Sang-Wook 한국접착및계면학회 2001 접착 및 계면 Vol.2 No.3

${\gamma}$-APS (${\gamma}$-aminopropyltriethoxysilane)로 표면처리된 천연제올라이트와 에폭시 수지 복합 재료의 표면 자유 에너지, 인상강도 및 계면 모폴로지에 대해 연구하였다. 표면처리하지 천연제올라이트의 표면 자유에너지 성분 중에서 무극성 성분인 Lifshitz-van der Waals 성분, ${\gamma}{\frac{LW}{SV}}$는 $19.22mJ/m^2$이었고, 극성 성분인 Lewis acid-base 성분, ${\gamma}{\frac{AB}{SV}}$는 $15.27mJ/m^2$이 있다. ${\gamma}$-APS의 처리농도가 증가함에 따라 ${\gamma}{\frac{LW}{SV}}$값은 증가하였지만 ${\gamma}{\frac{AB}{SV}}$는 감소하였으며, 이는 ${\gamma}$-APS의 소수성 성분인 알킬기의 영향이 친수성 기인 아민이나 수산기의 영향보다 커지기 때문이다. 인장강도와 Young율은 ${\gamma}$-APS 처리에 의해 개선되었으며, SEM 분석에 의해 계면특성이 향상되었음을 확인하였다. Epoxy composites filled with natural zeolite was prepared to investigate the effects of silane coupling agent, ${\gamma}$-APS (${\gamma}$-aminopropyltriethoxysilane)on the surface free energy, tensile properties and interfacial morphology. The value of Lifshitz-van der Waals component, ${\gamma}{\frac{LW}{SV}}$ for polar was $19.22mJ/m^2$ and increased, while that of Lewis acid-base component, ${\gamma}{\frac{AB}{SV}}$ for polar was $15.27mJ/m^2$ and decreased with the increasing content of ${\gamma}$-APS treatment. It is due that the surface of the zeolite is more coated by hydrophobic of alkyl group than hydrophilic amine or hydroxyl group. The tensile strength and Young's modulus of epoxy system were improved by the treatment with ${\gamma}$-APS due to the strong interface bonding, which was confirmed by SEM.

PET/CT 감쇠보정시 다양한 CT Kernel 적용에 따른 유용성 평가

이재영,성용준,윤석환,박찬록,이홍재,노경운,Lee, Jae-Young,Seong, Yong-Jun,Yoon, Seok-Hwan,Park, Chan-Rok,Lee, Hong-Jae,Noh, Kyung-Wun 대한핵의학기술학회 2017 핵의학 기술 Vol.21 No.2

PET/CT 영상 재구성시 감쇠보정맵을 사용하여 영상재구성에 적용한다. 감쇠보정 맵의 CT parameter을 변경하여 PET/CT 영상 재구성 할 때 적용하여 SUVmax에 어떤 영향을 미치는지 비교 평가해보고자 한다. 장비는 Biograph mCT 64를 사용하였고 Phantom은 NEMA IEC Body Phantom을 사용하였다. 실험을 위해 환자는 2017년 2월에서 3월까지 본원 PET/CT 검사를 시행한 환자 20명을 대상으로 Lung, Liver, Bone에 관심영역을 선택하여 기존 08f AC, 45f medium, 80f ultra sharp 방식의 CT kernel을 적용한 감쇠보정맵을 사용하여 PET/CT 영상 재구성에 도입 후 방사능 농도(kBq/mL), SUVmax, SD(standard deviation) 변화 유무를 평가하였다. Phantom 방사능 농도 측정 결과 B08f AC 대비 B45f 0.96%, B80f 6.58% 증가하였고 B08f AC 대비 B45f 0.86%, B80f 6.54%각각 증가하였고, SD의 경우 B08f AC 대비 B45f 1.27%, B80f 6.96% 증가하였다. 환자에서 부위별 SUV는 Lung에서 B08f AC 대비 B45f 1.6%, B80f 6.6%, Liver에서 B08f AC 대비 B45f 0.7%, B80f 4.7%, Bone에서 B08f AC 대비 B45f 1.3%, B80f 6.2% 증가를 보였다. 부위별 SD는 Lung에서 B08f AC 대비 B45f 6.2%, B80f 15.4%, Liver에서 B08f AC 대비 B45f 2.1%, B80f 11%, Bone에서 B08f AC 대비 B45f 를 사용할 때 2.3%, B80f 14.7% 증가를 보였다. CT Kernel변화에 따라 sharpness noise와 영상의 질은 변화를 보였으나 SUVmax와 SD는 통계적으로 유의한 차이가 없었다.(P>.05). 핵의학 영상은 정량적인 평가가 중요하다 따라서 부위에 따라 CT kernel이 적절하게 조절되고 noise level이 낮은 감쇠보정 맵을 사용하여 PET/CT 재구성시에 적용하여 정량적 평가에 오류를 줄이는 것이 중요하다고 사료되므로 따라서 같은 부위라 할지라도 sharpness noise가 인위적으로 증가된 kernel을 사용하는 것보다 noise가 낮은 kernel을 사용하는 것이 SD편차를 줄이고 정량적인 평가에 오류를 적게 하여 정확한 진단과 SUV 측정에 유용할 것으로 사료된다. Purpose Recently PET/CT image's attenuation correction is used CTAC(Computed Tomgraphy Attenuation Correction). it can quantitative evaluation by SUV(Standard Uptake Value). This study's purpose is to evaluate SUV and to find proper CT kernel using CTAC with applied various CT kernel to PET/CT construction. Materials and Methods Biograph mCT 64 was used for the equipment. We were performed on 20 patients who had examed at our hospital from february through March 2017. Using NEMA IEC Body Phantom, The data was reconstructed PET/CT images with CTAC appiled various CT kernel. ANOVA was used to evaluated the significant difference in the result. Results The result of measuring the radioactivity concentration of Phantom was B45F 96% and B80F 6.58% against B08F CT kernel, each respectively. the SUVmax increased to B45F 0.86% and B80F 6.54% against B08F CT kernel, In case of patient's parts data, the Lung SUVmax increased to B45F 1.6% and B80F 6.6%, Liver SUVmax increased to B45F 0.7% and B80F 4.7%, and Bone SUVmax increased to B45F 1.3% and B80F 6.2%, respectively. As for parts of patient's about Standard Deviation(SD), the Lung SD increased to B45F 4.2% and B80F 15.4%, Liver SD increased to B45F 2.1% and B80F 11%, and Bone SD increased to B45F 2.3% and B80F 14.7%, respectively. There was no significant difference discovered in three CT kernel (P >.05). Conclusion When using increased noise CT kernel for PET/CT reconstruction, It tends to change both SUVmax and SD in ROI(region of interest), Due to the increase the CT kernel number, Sharp noise increased in ROI. so SUVmax and SD were highly measured, but there was no statistically significant difference. Therefore Using CT kernel of low variation of SD occur less variation of SUV.

QCA 를 이용한 CO2 의 전기화학적 환원에 따른 구리전극의 특성 연구

이재영,탁용석 ( Jae Young Lee,Yong Sug Tak ) 한국화학공학회 1996 화학공학의이론과응용 Vol.2 No.2

건축 형태에 내재하는 사회적 가치에 대한 연구 - 낙원상가를 중심으로 -

이재영,김마리,윤재신,Lee, Jae-Young,Kim, Ma-Rie,Yoon, Chae-Shin 한국주거학회 2015 한국주거학회 논문집 Vol.26 No.3

This study is conducted to understand the social value of Nakwon building, which has been instilled in the architecture of the building, through an analysis of formative elements unique to the center. The architectural characteristics of Nakwon building have been formed over a long period of time in relation with its surroundings and social change. Before looking into the formation of the center, this study investigates the street network planning of downtown. The street network was planned to expand in a north-south direction in order to accommodate a future increase of traffic volume as a result of industrialization and a population increase in downtown. This was manifested in expanding Samilro Street which passes through the lower part of Nakwon building, as well as in forming the architecture of the center. That is, the center has formed a symbiotic relationship with its surrounding areas, sharing space with them. The interior of the center seems to have an independent form while keeping a relationship with its external format, but it is seeking change internally in response to external change. Interior space has been departmentalized over time since its initial establishment, and the internal traffic has also been subdivided accordingly. This is attributable to the fact that social change in the neighboring areas affected the formation of Nakwon building, and that in turn contributed to forming the unique characteristics of the building. Nakwon building is one of the deteriorated buildings in downtown Seoul. However, it was built out of social need to share space within the city, and it has been changed according to social need for the 'distribution of space within the building.

폐교 사립대학 기록물 관리 개선 방안에 관한 연구

이재영,정연경,Lee, Jae-Young,Chung, Yeon-Kyoung 한국기록관리학회 2019 한국기록관리학회지 Vol.19 No.4

최근 인구절벽의 위기 속에 학령인구가 지속적으로 감소하고, 대학의 입학충원율도 급감하면서 교육부는 향후 3년 내 국내 대학의 38개교가 폐교할 것이라는 예측을 하는 등 현재 한국의 대학은 폐교라는 위기에 직면하고 있다. 폐교대학에서 생산된 기록물에 대한 후속조치 및 관리에 대한 문제는 대학기록물 자체가 갖는 법적 행정적 역사적 정보적 가치를 고려할 때, 주요하게 논의되어야 할 사항 중에 하나이다. 그러므로 폐교대학 기록물 역시 적법한 절차에 따라 체계적으로 관리될 필요가 있는데, 현재 폐교대학 기록물 관리에 관한 실질적이고 뚜렷한 법제적 기준이 부재하고, (폐교)대학기록물이라는 특성 및 개별 학교의 현실과 특수성에 부합하는 관리기준은 부족한 실정이다. 이에 본 연구에서는 관리기준이 모호한 폐교대학 기록물 관리실태를 파악하고, 그 문제점을 분석하여 폐교대학 기록물 관리의 개선 방안으로 통합관리체계를 제시하였다. The recent demographic cliff caused the schooling population to steadily decline and the number of college admissions to sharply drop, which led to the prediction of the Ministry of Education wherein 38 universities in Korea will be closed within the next 3 years. As such, the legal, administrative, historical, and informational values of university records shed light on the importance of the follow-up process and management of closed university records. Although closed university records need to be systematically managed according to legal procedures similar to other public records, there is no practical and clear legal standard for the management of such records at present. Moreover, management standards considering the characteristics of (closed) university records and individual universities' situations and specificity have been insufficient. This study, therefore, examines the ambiguous standards for closed university records management and analyzed relevant problems. Furthermore, an integrated management system is suggested as a way to improve the records management of closed universities.

ADHD 학생의 동네환경과 특별활동의 경험에 대한 비교연구

이재영,최범성,강동묵,김지훈,Lee, Jae-Young,Choi, Bum-Sung,Kang, Dong-mug,Kim, Ji-Hoon 대한생물정신의학회 2018 생물정신의학 Vol.25 No.3

Objectives The purpose of this study is to investigate the differences between a attention deficit hyperactivity disorder (ADHD) group and a general student group in terms of the perception of the residential environment and periodic activities outside the classroom. Methods The patient group consisted of 62 outpatients or inpatients at the Department of Pediatric Psychiatry, and 49 patients diagnosed with ADHD were selected. For the control group, 3727 youths in elementary schools, middle schools, and high schools of one city were asked to fill out questionnaires. Of the 1717 respondents who responded to the questionnaires, 245 were selected for a patient-controlled study. The differences between the patient group and the control group were compared using the chi-squared test (${\chi}^2$ test). Results There was a significant difference between the patient group and the control group in areas where students responded by "My neighborhood is dirty and littered (p < 0.05)". There was also a significant difference between the patient group and the control group in terms of having more than one club activity per month (p < 0.05). Conclusions It was found that the patients with ADHD are more aware of perceived negative aspects of the area in which they reside, thus reflecting their anxiety. In addition, it was also found that the patient group did not partake in as many social activities as the control group.

인상채득방법과 방향에 따른 인상체의 정밀성과 체적 안정성에 관한 연구

이재영,임주환,조인호,Lee, Jae-Young,Lim, Ju-Hwan,Cho, In-Ho 대한치과보철학회 1999 대한치과보철학회지 Vol.37 No.5

Accurate reproduction of intraoral tissue is essential in the fabrication of fixed prosthesis. This selection of impression material and method is very important. In this study, vinyl polysiloxane type impression material $Panasil^{(R)}$ was used. Three impression methods ; one-step technique, individual tray technique, and individual tooth tray technique using the vinyl polysiloxane type bite registration material $Futar^{(R)}$ Occlusion, were used to take horizontal and vertical impression. Improved stone models were fabricated. The amount of occlusal surface discrepaneies, interabutment distance discrepancies, amount of marginal defect were evaluated with the $X-PLAN360d^{(R)}$ and photoscanning. The results were as follows. 1. There was no significant difference in occlusal surface according to the directions and techniques of impression taking. 2. There was no significant difference in interabutment distance discrepancies according to the directions and techniques of impression taking 3. There was no significant difference in marginal discrepancies according to the direction of impression taking but there was significant difference between one-step technique and individual tray technique, individual tooth tray technique (P<0.05). Taken together, these results suggest that individual tray technique and individual tooth tray technique are more accurate for impression taking than one-step technique.

홍수기 다기능보 운영을 고려한 수리학적 모형 개발

이재영,김기영,신동훈,Lee,Jae Young,Kim,Ki Young,Shin,Dong Hoon 한국방재학회 2014 한국방재학회논문집 Vol.14 No.3

홍수기 다기능보 운영에 따른 수리학적 영향을 검토하기 위해 내부경계조건 처리 및 세굴심 예측을 개선한 수리학적 모형을 개발하였다. 관측수위나 수위-유량관계곡선 설정을 통한 내부경계조건을 채택하고 있는 기존 범용모형에 비해 조절구조물 상하류의 다양한 계산수위 조건을 고려하여 고정보의 월류량과 가동보의 방류량을 계산할 수 있도록 하였으며 하류부 구조물에 미치는 영향을 분석하고자 하상재료의 토양특성치를 반영한 부정류 상태의 시간별 단기세굴심 변화를 예측하였다. 모형의 적용성을 검증하기 위해 기왕의 홍수사상을 적용하여 다기능보 운영에 따른 보 상하류 주요지점의 홍수위 변화와 다기능보의 방류량을 모의한 결과, 관측치를 잘 재현하고 있음을 확인하였다. 다기능보의 다양한 운영조건에 대하여 모의한 결과, 가동보에 의한 수위상승 효과와 고정보에 의한 세굴심 상승효과가 나타났다. 이를 통해 홍수기 가동보의 운영룰에 따라 상하류 홍수위 상승과 하류부 세굴심 발생을 최소화시키는 것이 가능함을 알 수 있었다. An advanced hydraulic model was developed by improving the numerical implementation of internal boundary condition and the prediction of scour depth to analyse hydraulic effects in operation of multi-function weir during the flooding season. The proposed model calculates overflow at fixed weir and gate discharge controlled by movable weir depending on the computed water stages on the upstream and downstream reach compared to conventional model applying internal boundary condition specified as prescribed stage or rating curve. In addition, it can predict time-dependent scour depth considering soil properties under unsteady state in order to investigate the hydraulic effects on bridge structure located downstream. A historical flood event was applied to demonstrate the verification of the model as simulation results were compared with observations on monitoring station. It was shown that the prediction of water stages, gate discharges, and scour depth enable gate operation rule to minimize the effect of flood stage rising by movable weir and scour depth development by fixed weir.

화학처리 및 금속이온 교환된 천연 제올라이트의 질소 흡착특성

이재영,심미자,김상욱 ( Jae Young Lee,Mi Ja Shim,Sang Wook Kim ) 한국공업화학회 1994 공업화학 Vol.5 No.6

경북 감포지역에서 산출되는 천연 제올라이트를 각기 다른 농도의 HCl과 NaOH로 화학처리한 시료와 금속 양이온 교환한 시료를 제조 하였다. 이들 시료에 대한 질소의 흡착특성을 25℃, 100∼760 torr의 범위에서 조사하였다. 산 처리한 시료의 질소 흡착량은 처리하기 전보다 감소하였으며, 알칼리 처리한 시료는 많이 증가하였다. 0.5N-HCl 처리 후 0.5N-NaOH로 연속처리한 경우 약 200% 정도 흡착량이 개선되었으나, 알칼리 처리 후 산으로 연속처리한 경우에는 오히려 감소하였다. Na^+, K^+, Cs^+를 이온교환한 경우 이온의 크기가 증가할수록 흡착량은 감소했으며, Mg^(2+), Ca^(2+), Ba^(2+)를 이온교환한 경우는 이온의 크기가 증가할수록 흡착량이 증가하였다. The characteristics of the nitrogen adsorption with natural zeolite produced in Kampo area according to the chemical treatment by HCl and/or NaOH or the exchanging metal ion were investigated in the pressure range of 100∼760torr at 25℃. The amount of nitrogen adsorption was followed at increment in the order of NaOH treatment>nontreatment>HCl treatment. Adsorption amount on natural zeolite treated with 0.5N-HCl/NaOH was improved about 200%, whereas that on natural zeolite treated with 0.5N-NaOH/HCl was decreased. When metal ion of natural zeolite was exchanged with Na^+, K^+ and Cs^+, adsorption amount of nitrogen was decreased as the size of ration was increased. But metal ion of natural zeolite was exchanged with Mg^(2+), Ca^(2+) and Ba^(2+), the amount of nitrogen adsorption was increased.

천연 제올라이트 / 에폭시 복합재료의 경화반응 속도론

이재영,천인숙,심미자,김상욱 ( Jae Young Lee,In Sook Chun,Mi Ja Shim,Sang Wook Kim ) 한국공업화학회 1996 공업화학 Vol.7 No.2

천연 제올라이트/에폭시 수지 복합재료의 경화반응 속도론을 연구하기 위해 DSC 분석법 중 승온적 방법을 이용하였다. 천연 제올라이트의 함량이 증가함에 따라 반응 시작온도와 발열피크의 온도가 낮아졌다. Diglycidyl ether of bisphenol A(DGEBA)/4,4`-methylene dianiline(MDA)/malononitrile(MN, 10phr)에 제올라이트를 20phr 충전한 경우에는 하나의 발열피크가 나타나며, 30phr인 경우에는 shoulder가 나타났다. 40phr의 제올라이트가 충전된 경우에는 발열피크가 두 개로 분리되며, 첫번째 발열피크의 활성화에너지, Ea₁은 12.30 kJ/㏖이고, 두번째 발열피크의 활성화에너지, Ea₂는 12.70 kJ/㏖이었다. Natural zeolite/epoxy resin composites were prepared and the cure kinetics was studied by dynamic DSC analysis. With the increment of natural zeolite content, the reaction starting temperature and the exothermic peak temperature were decreased. When diglycidyl ether of bisphenol A(DGEBA)/4,4`-methylene dianiline(MDA)/ malononitrile(MN, 10phr) was filled with 20phr of zeolite, DSC thermogram had one peak and when it was filled with 30phr of zeolite, a shoulder appeared on the DSC thermogram. With the filling of 40phr of zeolite, DSC thermogram was separated into two peaks and the activation energy of the first peak, Ea₁ was 12.30 kJ/㏖ and that of the second peak, Ea₂ was 12.70 kJ/㏖.