암컷 hGHTg 비만 쥐에서 輕身解脂丸 (GGT1)에 의한 비만관련 유전자 mRNA 발현의 변화

윤기현(Ki Hyeon Yoon),윤미정(Michung Yoon),김훈(Hoon Kim),신순식(Soon Shik Shin) 한의병리학회 2006 동의생리병리학회지 Vol.20 No.2

Safety - Critical Real - Time Operating System의 설계 및 구현

윤기현(Ki-Hyun Yoon),김용희(Yong-Hee Kim),박희상(Hee-Sang Park),성영락(Yeong Rak Seong),이철훈(Cheol-Hoon Lee) 한국정보과학회 2003 한국정보과학회 학술발표논문집 Vol.30 No.1A

실시간 운영체제(Real-Time Operating System)는 그 실행환경상 시스템이 예상치 못한 특정 이벤트가 발생하는 악 조건속에서도 태스크 수행의 데드라인을 초과하지 않도록 시간적인 측면의 determinism 을 보장하는 안정된 스케쥴링 기능을 갖춘 운영체제이다. 또한, 예상치 못한 fault를 미연에 방지할 수 있는 장치를 가지고 있어야 한다. 본 논문에서는 예상치 못한 fault 를 미연에 방지하기 위하여 필요한 운영체제를 설계 및 구현하는데 그 목적이 있다.

실시간 운영체제를 위한 Graphic User Interface 의 설계

윤기현(Ki-Hyun Yoon),김용희(Yong-Hee Kim),박희상(Hee-Sang Park),이철훈(Cheol-Hoon Lee) 한국정보과학회 2002 한국정보과학회 학술발표논문집 Vol.29 No.2Ⅰ

실시간 운영체제를 이용하는데 있어서 GUI(Graphic User Interface)는 실시간 운영체제를 이용한 제품을 사용하는 사람들에게 제품에 대한 편한 환경을 제공하는데 목적이 있다. 이에 본 논문에서는 실시간 운영체제(Real Time Operating System)상에서 GUI를 구현하는데 있어서 중요한 부분들을 고려하고, 실시간 운영체제에 알맞은 환경을 구축하기 위한 Graphic User Interface를 설계하였다.

[연료 및 윤활유부문] 맥퍼슨 스트러트의 부품유격에 따른 소음영향에 관한 연구

윤기현(Kihyun Yoon),이재용(Jaeyong Lee) 한국자동차공학회 2000 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

A recent trend within the automotive industry has been an emphasis on the reduction of noise future vehicle applications. This trend created a need for the development of methods to predict the noise within the vehicle environment. In particular, the development of models for the reduction of noise must be based the result that account for the dynamic property between components. The noise vehicle in driving is mostly transferred through the suspension system or created from the damper. So, the information of parameter for the damper noise is very important to characterize the vehicle noise. After the loading conditions is performed with real vehicle installing condition, this paper describes a finite element model of a damper model with the clearance between and rod guide and rattle the suspension system. The results of a study of the damper noise subjected to dynamic loading condition and rattle the suspension system. The results of a study of the damper noise subjected to dynamic loading condition are presented. Additionally, the effects of the clearance in the damper are considered and the results are displayed.

교육부 감사에 대한 시도교육청의 감사수용성 연구

윤기현(Yoon, Ki-Hyun),박균열(Park Kyun-Yeal) 한국교육행정학회 2016 敎育行政學硏究 Vol.34 No.5

본 연구는 교육부의 감사에 대해 교육부와 시․도교육청간 감사수감의 인식차이를 분석하여 감사수용성에 미치는 영향 요인을 확인하기 위해 기관별로 감사수용성 영향요인을 확인하고 기관에 따라 각 요인이 감사수용성과 어떤 관계가 있는지 분석하였다. 교육부 감사관실 소속직원 및 서울․경기교육청 소속 감사수감 유경험 직원 192명이 응답한 설문조사 자료를 대상으로 상관분석과 분산분석 및 회귀분석을 실시하였다. 연구 결과에 의하면 첫째, 교육부 감사에 대한 인식 확인 결과 교육부와 시․도교육청 모두 감사의 목적은 사후적 관리가 중요한 비중으로 인식하고 있었으며, 교육부 감사 시 외부전문가 필요 분야에 대해서는 교육부와, 시․도교육청에서는 각각 다른 요구를 나타내고 있었다. 둘째, 교육부와 시․도교육청의 감사수감 영향요인 및 감사수용성의 인식차이를 확인한 결과 환경적 요인을 제외한 모든 요인에서 교육부 가 시․도교육청보다 긍정적으로 평가하고 있었다. 셋째, 교육부와 시․도교육청 간의 감사수감 영향요인 중 감사수용성에 가장 크게 영향을 미치는 요인은 교육부와 시․도교육청 공통으로 행위자 요인으로 나타났으며, 교육부에 비해 시․도교육청에서 행위자요인이 감사수용성에더 큰 영향을 미치는 것으로 나타났다. 이를 바탕으로 결론 및 제언을 제시하였다. This study aims to figure out the factors which influence the auditor's acceptance and to seek a practical solution which may contribute to the auditing process by the Ministry of Education by comparing the perceptual differences of auditing between the office of education in-local and the Ministry of Education . With the purpose of the research, the survey was conducted on 192 staffs of the Seoul Metropolitan office of Education (SMOE) and the Gyeonggi Provincial Office of Education (GPOE) as well as the Audit and Inspection department of the Ministry of Education (MOE), who had experienced MOE auditing. The correlations, one-way ANOVAs, and Regressions were performed to analyze the data. First, as for the purpose of MOE auditing, all the officers responded the post management was most important. On the other hand, MOE was observed to have different opinions from SMOE and GPOE considering the need for outside experts during the MOE audit. Second, regarding the perceptual differences of the influential factors on receptivity to MOE auditing, MOE was shown to have more positive attitudes toward all the factors except for the environmental one than SMOE and GPOE. Last, 'the actor-related-factor' was found to be the most significant factor that had affected the receptivity of auditors and auditees in MOE auditing, and it had more impact on SMOE and GPOE than on MOE. Based on the results, the conclusion and implications in this study were provided.

신체부위별 측정변인에 따른 경신강지환16의 비만 개선효과 평가

정양삼,윤기현,최승배,윤미정,신순식,Jung, Yang-Sam,Yoon, Ki-Hyeon,Choi, Seung-Bae,Yoon, Mi-Chung,Shin, Soon-Shik 대한한의학방제학회 2008 大韓韓醫學方劑學會誌 Vol.16 No.1

In this study, we measured body mass index, visceral fat ratio and 6 parts of body, neck circumference, circumference of upper arm, chest circumference, abdomen circumference, hip circumference, and thigh circumference by bioimpedence analysis system, after taking Gyeongshingangjeehwan16 (GGEx16) in five months except the first period before taking GGEx16 on 49 women who are obesity or high-level obesity. In order to examine the significance test for the effect of obesity improvement of GGEx16, we practices repeated measure ANOVA with values of measurement variables in 6 monthly times. As a result of all measurement variables, there were significant difference (P-value=0.001). Therefore, we can say that GGEx16 is effective about obesity improvement. As it dramatically decreased between second measure period and first measure period for all measure variables, we can see that there were the most effect of GGEx16 in the first time after taking GGEx16. It is known that a important measurement variable to have a effect for obesity improvement about two variable which are body mass index and visceral fat ratio is waist circumference through correlation analysis. The result of whether there are differences to effect of obesity improvement for GGEx16 around the climacteric, there were significant difference for the effect of obesity improvement for GGEx16 around the climacteric about all parts of body (P-value=0.001). There were also powerfully difference in effect of obesity improvement for GGEx16 around the climacteric about all parts of body (P-value=0.001). Especially, the climacteric before is more effective than the climacteric after in the aspect of the effect of GGEx16.

The Effect of CuO-V2O5 Addition on Microwave Dielectric Properties of (Pb0.45Ca0.55)[(Fe0.5Nb0.5)0.9Sn0.1]O3 Ceramics

Jong-Yoon Ha,최지원,최두진,윤석진,김현재,윤기현 한국세라믹학회 2004 한국세라믹학회지 Vol.41 No.1

The effect of x wt.% CuO – y wt.% V2O5 content on the microwave dielectric properties of (Pb0.45Ca0.55)[(Fe0.5Nb0.5)0.9Sn0.1]O3 (PCFNS) ceramics was investigated. In order to decrease the sintering temperature and use as a low temperature co-firing ceramics (LTCC), CuO - V2O5 are added in the PCFNS. The bulk density, dielectric constant(r) and quality factor(Q•f0) increased with increase in CuO content within a limited value. The microwave properties were degraded with increases in V2O5 content. The temperature coefficient of the resonant frequency(f) of PCFNS was shifted to positive value abruptly with increasing the V2O5 content, while the f was slightly shifted to positive value with increasing the CuO content. The optimized microwave properties, r = 88, Q•f0 = 6100 (GHz), and tf =18 ppm/℃, were obtained in (Pb0.45Ca0.55){(Fe1/2Nb1/2)0.9Sn0.1}O3 with 0.2 wt.% CuO – 0.05 wt.% V2O5 and sintered at 1000℃ for 3h. The relationship between the microstructure and microwave dielectric properties of ceramics was studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM).

1 keV $Ar^+$이온빔으로 개질된 polytetrafluoroethylene (PTFE) 위의 구리 박막 증착

조준식,윤기현,고석근,Cho, Jun-Sik,Yoon, Ki-hyun,Koh, Seok-Keun 한국재료학회 2000 한국재료학회지 Vol.10 No.1

1 keV $Ar^+$ 이온빔을 이용하여 polytetrafluoroethylene (PTFE)의 표면을 개질하고 그 위에 $5000\;{\AA}$의 구리 박막을 이온빔 스퍼터링법을 이용하여 증착하였다. 이온빔 조사에 의하여 PTFE의 표면에는 cone이 형성되며 cone의 높이는 이온 조사량이 증가함에 따라 점차로 증가함을 알 수 있었다. x-ray photoelectron spectroscopy (XPS) 분석을 통하여 조사된 PTFE의 표면에서는 이온 조사량이 증가함에 따라 Fls peak의 강도가 감소하며 이는 F 원자의 선택적인 스퍼터링에 기인한 것으로 생각된다. 또한 이온 조사에 의해 생성된 불안정한 사슬들은 crosslinking에 의하여 새로운 C-F 계열의 결합들을 생성하였다. 이온빔 스퍼터링법에 의하여 증착된 구리 박막은 PTFE 표면의 cone을 따라 균일하게 증착되며 PTFE의 표면 거칠기가 증가함에 따라 (111) 방향으로 우선 성장함을 알 수 있었다. 증착된 구리 박막의 비저항은 개질전 PTFE의 $2.7{\mu}{\Omega}cm$에서 $1{\tiems}10^{16}/\textrm{cm}^2$의 이온 조사량으로 개질된 PTFE의 $4.3{\mu}{\Omega}cm$까지 이온 조사량에 따라 점차로 증가하였다. $1{\tiems}10^{17}/\textrm{cm}^2$의 이온 조사량으로 개질된 PTFE 위에 증착된 구리 박막의 갑작스런 비저항 증가는 구리 박막의 단락에 의한 것으로 보인다. A surface of polytetrafluoroethylene(PTFE) was modified with changing ion doses by 1 keV $Ar^+$ ion irradiation and Cu films having thickness $5000\;{\AA}$ were deposited on the modified PTFE. The SEM study showed that the surface texture of modified PTFE was in the form of cones whose height increased depending on ion doses. Through XPS spectra, it was found that the intensity of F ls peaks decreased with ion doses by preferential sputtering of F atoms and the C-C and / or C-F chains were formed by the crosslinking in the newly unstable chains. Cu films were deposited uniformly along the filaments formed on the modified PTFE. In x-ray diffraction (XRD) spectra of deposited Cu films on modified PTFE, a preferred orientation along (111) and (200) planes was found and the peak intensity of (111) plane increased as surface roughness of modified PTFE increased. The resistivity of Cu films was changed from $2.7{\mu}{\Omega}cm$ of unmodified PTFE to $4.3{\mu}{\Omega}cm$ of modified PTFE at ion dose of $1{\times}10^{16}/\textrm{cm}^2$ and the abrupt increase of resistivity in the modified PTFE at ion dose of $1{\times}10^{17}/\textrm{cm}^2$ was due to being cut off the film which resulted from the increased surface roughness.

FHD 공정으로 제조한 실리카 막의 저온 고밀화

김태홍,윤기현,Kim, Tae-Hong,Yoon, Ki-Hyun 한국세라믹학회 2002 한국세라믹학회지 Vol.39 No.3

화염가수분해증착(FHD : Flame Hydrolysis Deposition)공정으로 평면형 광수동소자를 구현하기 위한 1050$^{\circ}C$의 저온에서 실리카(silica)막을 형성하였다. 본 연구는 실리카 막을 저온에서 형성하기 위하여 B, P 의 함량을 증가시키면서 고밀화 온도 변화 및 고밀화 분위기에 따른 미세구조의 변화 등 고밀화 영향과 광학적 특성을 관찰하였다. He 분위기에서 고밀화한 경우 적정 고밀화 온도를 1050$^{\circ}C$까지 낮출 수 있었고, 그 결과 표면조도(Surface Roughness)가 5.6nm인 균질한 실리카 막을 저온에서 형성할 수 있었다. For planar optical devices, silica film deposited by FHD was fabricated at low temperature. To prepare silica film at low temperature, we have changed B, P amounts and investigated consolidation effect with varying consolidation temperature and atmosphere on microstructural change, and also observed optical property. The optimum consolidation temperature in He was lower than that of other atmosphere, its temperature could be lowered to 1050$^{\circ}C$. As a result, the roughness of flat silica film prepared at 1050$^{\circ}C$ showed 5, 6nm.

RF 스퍼터링법으로 사파이어 기판 위에 성장한 ZnO와 ZnO : A1 박막의 질소 및 수소 후열처리에 따른 Photoluminescence 특성

조정,윤기현,정형진,최원국,Cho, Jung,Yoon, Ki-Hyun,Jung, Hyung-Jin,Choi, Won-Kook 한국재료학회 2001 한국재료학회지 Vol.11 No.10

2wt% $Al_2O_3-doped$ ZnO (AZO) thin films were deposited on sapphire (0001) single crystal substrate by parellel type rf magnetron sputtering at 55$0^{\circ}C$. The as-grown AZO thin films was polycrystalline and showed only broad deep defect-level photoluminescence (PL). In order to examine the change of PL property, AZO thin films were annealed in $N_2$ (N-AZO) and $H_2$ (H-AZO) at the temperature of $600^{\circ}C$~$1000^{\circ}C$ through rapid thermal annealing. After annealed at $800^{\circ}C$, N-AZO shows near band edge emission (NBE) with very small deep-level emission, and then N-AZO annealed at $900^{\circ}C$ shows only sharp NBE with 219 meV FWHM. In Comparison with N-AZO, H-AZO exhibits very interesting PL features. After $600^{\circ}C$ annealing, deep defect-level emission was quire quenched and NBE around 382 nm (3.2 eV) was observed, which can be explained by the $H_2$passivation effect. At elevated temperature, two interesting peaks corresponding to violet (406 nm, 3.05 eV) and blue (436 nm, 2.84 eV) emission was firstly observed in AZO thin films. Moreover, peculiar PL peak around 694 nm (1.78 eV) is also firstly observed in all the H-AZO thin films and this is believed good evidence of hydrogenation of AZO. Based on defect-level scheme calculated by using the full potential linear muffin-tin orbital (FP-LMTO), the emission 3.2 eV, 3.05 eV, 3.84 eV and 1.78 eV of H-AZO are substantially deginated as exciton emission, transition from conduction band maximum to $V_{ Zn},$ from $Zn_i$, to valence band maximum $(V_{BM})$ and from $V_{o} to V_BM}$, respectively.