65세 이상의 노령층에서 고지혈증의 위험요인

김용배,장원기,황보영,김화성,안규동,이병국,이용진,김세훈,김승수,김승훈,김영록,김웅빈,이성수 순천향의학연구소 2006 Journal of Soonchunhyang Medical Science Vol.12 No.1

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도장작업시 유해인자들의 노출수준과 작업환경관리실태

이세기,문덕환,이채관,황용식,선병관,손병철,김대환,이창희,김휘동,이채언 인제대학교 백병원 2002 仁濟醫學 Vol.23 No.5

Objectives: For the purpose of preparing the fundamental data and assessing the status of exposure level of chemical substances in painting process. Methods and Materials: The author determined the concentration of organic solvents, lead(Pb), Chromium(Cr), and Toluene-2, 4-diisocyanate(TDI) in air of painting process to 90 industries classified by 15 types of manufacturing industry during a period from Jan. 1st 2001 to Dec. 31st 2001. Results: The results were as follows: 1. The geometric mean level of each chemical substance was 0.1706 ppm for exposure index in organic solvents, 0.0019㎎/㎥ for Pb, 0.0024 ㎎/㎥ for Cr, and 0.0004ppm for TDI, respectively. 2. The exposure level of each chemical substances by type of painting was the highest in dipping and brush painting for organic solvent, in spray-painting for TDI, and in spray gun-painting for Pb and Cr, respectively. 3. The exposure level of each chemical substances by type of local ventilation equipment was higher in enclosed and booth type for organic solvents. Cr, and TDI, and in exterior type for Pb, respectively than those of other types. 4. The exposure level of each chemical substances by type of hazardous material arresting media was higher in using water for organic substances, in using bag filter for Pb, TDI, respectively than those of other types. Conclusion: According to above results, this study suggests that the exposure level by type of industry exceeded the exposure level in wooden furniture and metal furniture manufacturing industry for organic solvents and Pb, respectively.

복합 산화법과 MEMS 기술을 이용한 RF용 두꺼운 산화막 에어 브리지 및 공면 전송선의 제조

김국진,박정용,이동인,이봉희,배영호,이종현,박세일 한국센서학회 2002 센서학회지 Vol.11 No.3

본 논문에서는 양극반응과 복합 산화법( H_2O/O_2 분위기에서 500℃, 1시간 열산화와 1050℃, 2분간 RTO(Rapid Thermal Oxidation) 공정)을 이용한 두꺼운 OPSL(Oxidized Porous Silicon Layer)을 형성하여 이를 마이크로머시닝 기술을 이용함으로써 10 ㎛두께의 OPS(Oxidized Porous Silicon) 에어 브리지를 제조하고, 그 위에 전송선로를 형성하여 그 RF 특성을 조사하였다. OPS 에어 브리지 위에 형성된 CPW(Coplanar Waveguide)의 손실이 OPSL 위에 형성된 전송선의 삽입손실보다 약 2 dB 정도 적은 것을 보여주었으며, 반사손실은 OPSL 위에 형성된 전송선의 반사손실보다 적으며 약 -20 dB를 넘지 않고 있다. 본 연구에서 개발한 산화된 다공질실리콘 멤브레인 및 에어 브리지 구조는 CMOS 공정 후에 사용 가능하며, 초고주파 회로 설계시 편리성과 유용성을 제시하고 있다. This paper proposes a 10 ㎛ thick oxide air-bridge structure which can be used as a substrate for RF circuits. The structure was fabricated by anodic reaction, complex oxidation and micromachining technology using TMAH etching. High quality films were obtained by combining low temperature thermal oxidation (500 ℃,1 hr at H_2O/O_2) and rapid thermal oxidation (RTO) process (1050 ℃, 2min). This structure is mechanically stable because of thick oxide layer up to 10 ㎛ and is expected to solve the problem of high dielectric loss of silicon substrate in RF region. The properties of the transmission line formed on the oxidized porous silicon (OPS) air-bridge were investigated and compared with those of the transmission line formed on the OPS layers. The insertion loss of coplanar waveguide (CPW) on OPS air-bridge was (about 2 dB) lower than that of CPW on OPS layers. Also, the return loss of CPW on OPS air-bridge was less than about - 20 dB at measured frequency region for 2.2 mm. Therefore, this technology is very promising for extending the use of CMOS circuitry to higher RF frequencies.

Improved Internal Quantum Efficiency and Light-Extraction Efficiency of Organic Light-Emitting Diodes via Synergistic Doping with Au and Ag Nanoparticles

Cho, Changsoon,Kang, Hyunbum,Baek, Se-Woong,Kim, Taesu,Lee, Changyeon,Kim, Bumjoon J.,Lee, Jung-Yong American Chemical Society 2016 ACS APPLIED MATERIALS & INTERFACES Vol.8 No.41

<P>This paper reports the distinct roles- of Au and Ag nanoparticles; (NPs) in organic light-Orating-diodes (OLEDS) depending on their sizes. Au and Ag-NPs that.are 40 arid 50 nm in size, respectively, are the most effective for enhancing the performance of green: OLEDs. The external quantum efficiencies (EQEs): of green OLEDs doped with An and Ag N.Pg, (40 and 50 rim, respectiVely) are improved by 29.5% and 36.1%, respectively, while the power. efficiencies (PE8) are enhanced by 47.9% and 37.5%, respectively. Furthermore, combining the Au and Ag NPs produces greater enhancements. The EQE and PE of the coci-oped OLEDs are improved by 63.9% and 68.8% respectively,-.through the synergistic behavior of the different NPs. Finite difference time-domain simulations confirm that the localized surfaee:plasmon resonance of the Au NPs near 580 nth improves the radiative recombination rate (k(rad)) of green-light emitters locally (<50 pm), while the Ag NPs cause relatively long, range and broadband enhancements in k(rad). The-Simulations of 'various domain sizes. Verify that the light-extraction efficiency (LEE),can, be enhanced by More than 4.2% by applying Ag NPS.. Thus, size-controlled Au and Ag NPs can synergistically enhance LEDS by improving both the internal quantum efficiency and LEE.</P>

지난 4년간 학회지 "신경정신의학" 심사 평가보고

오병훈,권준수,남궁기,김승현,지익성,김창윤,하규섭,박원명,김성곤,오강섭,김정범,이수정,정한용,이창욱,박용천,이영문,김세주,이병욱 大韓神經精神醫學會 2005 신경정신의학 Vol.44 No.5

Four Years Reports of "Journal of Korean Neuropsychiatric Association" during 2001 to 2005 were evaluated by 18 Editorial Board of Korean Neuropsychiatric Association. We investigated the articles to specific fields and rejection rate etc. by different section chiefs. Although several problems concerning review time duration and rejection guideline issues indicated but generally all reviewer processes proved relatively clear and concise criteria. Through these objective and systematic evaluation Processes, "Journal of Korean Neuropsychiatric Association" will develop a good journal.

주식매입선택권과 기업가치평가모형에 대한 연구

이세용 가톨릭대학교산업경영연구소 2003 産業經營硏究 Vol.- No.11

고령토로부터 알루미나 추출 잔분 활용에 관한 연구

이덕형,이용근,최세영 연세대학교 산업기술연구소 1992 논문집 Vol.24 No.2

Autoclaved hydrate of CaO-SiO₂-H₂O system was investigated according to CaO/SiO₂ mole ratio and the condition of hydrothermal treatment. Residual product for extraction of alumina from hydrochloric acid treated domestic kaolin and Ca(OH)₂ were used as the source of SiO₂ and CaO, respectively. The main crystalline phases were C-S-H(I), tobermorite, xonotlite and transformed in order of C-S-H(I) → tobermorite → xonotlite as hydrothermal temperature, time, CaO/SiO₂ mole ratio increase. The porosity and absorption were increased with increasing CaO/SiO₂mole ratio and hydrothermal treatment time. The bending strength was dependent on the balanced bond between the residual and hydrothermal products, and tended to be maximum at CaO/SiO₂ of 0.6, and hydrothermal temperature of 140℃.

협업 여과 기반의 교육용 컨텐츠 추천 시스템 설계

이용준,이세훈,왕창종 한국컴퓨터교육학회 2003 컴퓨터교육학회 논문지 Vol.6 No.2

협업여과는 흥미 있어하는 제품이나 개인화된 자료, 항목을 제공하기 의해 전체 집단의 의견을 반영하는 전자상거래에서 일반적으로 이용되는 기술이다. 협업여과는 정확하고 신뢰할 수 있는 도구로 입증되어 여러 분야의 전자상거래 영역에서 활용되고 있으나 아직까지 교육분야에는 한정적으로 적용되고 있다. 본 논문에서는 교육용 컨텐츠 추천에 사용자의 평가 점수를 이용하는 협업여과 방식의 추천시스템을 설계하였으며, 사용자 정보를 이용하여 추천의 정확도를 향상시키기 위한 유사도 보정기법을 도입하였다. 평균절대오차(MAE)와 반응자작용특성(ROC)값을 이용하여 제안한 시스템이 기존의 협업여과방식보다 추천 효율이 우수함을 검증하였다. Collaborative Filtering is a popular technology in electronic commerce, which adapt the opinions of entire communities to provide interesting products or personalized resources and items. It has been applied to many kinds of electronic commerce domain since Collaborative Filtering has proven an accurate and reliable tool. But educational application remain limited yet. We design collaborative filtering recommendation system using user's ratings in educational contents recommendation. Also We propose a method of similarity compensation using user's information for improvement of recommendation accuracy. The proposed method is more efficient than the traditional collaborative filtering method by experimental comparisons of mean absolute error(MAE) and reciever operating characteristics(ROC) values.

우리나라 목재수요의 장기예측에 관한 연구

이병일,김세빈,권용대 충남대학교 농업과학연구소 1998 농업과학연구 Vol.25 No.1

This study not only carried out to grasp about the summarized characteristics of the relationship between international timber market and production trend of wood products, but also focused on the analysis of korean wood demand and the long-term forecast with econometric analysis. The result of regression analysis for wood demand in Korea is that coniferous roundwood demand(CIWD) is explained by coniferous foreign roundwood price(CWRI), Gross domestic product(GDP), a dummy variable. Non-coniferous roundwood demand(NCIWD)is explained by non-coniferous roundwood price(NCWRI), coniferous roundwood price(CWRI), a dummy variable. As the result of long-term forecast by base case, the total roundwood demand was forecasted 11,107,000㎥ in the year 2000, 11,781,000㎥ in 2005, 12,565,000㎥ in 2010. As the result of scenario 1, total roundwood demand was forecasted 11,027,000㎥ in 2000, 11,435,000㎥ in 2005, 11,952,000㎥ in 2010. And as the result by scenario 2, total roundwood demand was forecasted 11,341,000㎥ in 2000, 12,208,000㎥ in 2005 13,257,000㎥ in 2010.

분광 엘립소메트리의 응용을 위한 0차 Retardation Plate의 Alignment

이용달,박명규,김세덕,방경윤,안일신 한양대학교 이학기술연구소 2000 이학기술연구지 Vol.2 No.

A zero-order retarder was fabricated using two pieces of magnesium fluoride plates. In order to achieve desired zero-order retardation for specific wavelength, both the thickness of plates and the alignment of two fast axes were very important. We found that the alignment should be checked using broad band detection system for spectroscopic application, We devised alignment method by which the two fast axes lie perpendicularly to each other. The periodic oscillation feature in retardation angle versus wavelength disappeared with good alignment. We also developed calibration method to deduce the retardation angle over a wider spectral range using rotating compensator ellipsometer. 두 조각의 마그네슘 플로라이드 판을 이용한 0차 retarder를 제작하였다. 특정한 파장에 대하여 원하는 0차 retardation을 얻기 위해서는 판의 두께와 alignment가 매우 중요하였다. 분광학적인 응용을 위해서는 넓은 파장 영역을 측정할 수 있는 detection system의 사용이 필요하였다. 이를 이용하여 두 판의 fast axes가 서로 수직으로 놓이게 할 수 있는 alignment 방법을 개발하였다. 파장에 대한 retardation 각도에서의 주기적인 진동의 모양은 alignment를 잘하게 되면 사라지게 된다. 또한 rotating compensator ellipsometer를 사용 할 때 넓은 분광영역에 걸친 retardation angle을 측정해 낼 수 있는 calibration 방법을 개발하였다.