2중천이검출방식을 이용한 새로운 속도 측정회로

윤경섭,이무영,김우현,권우현 ( Kyung Sup Yoon,Moo Young Lee,Woo Hyun Kim,Woo Hyen Kwon ) 한국센서학회 1997 센서학회지 Vol.6 No.4

The measure of motor speed using encoder is difficult to detect accurate speed and direction in very low speed because the intervals between an encoder pulse and pulse are long. So various speed estimation techniques were proposed to have the good dynamic performance in low speed. And direction detection is so important as speed measurement in very low speed. But because the conventional direction detection circuit check the direction only 1 time in 1 period of each encoder pulses, so it has long delayed detection time in very low speed, thus accurate detection of direction is difficult. In this paper, we propose a 2 way edge det~tion method which can detect at the rising and falling edge of each encoder pulses. So it can check the direction 4 times in I period of each encoder pulses. Therefore if we use proposed method, we can reduce the detection time as 1/4 than that of conventional circuit and can detect more accurate speed and direction. And computer simulation and experiment is performed to verify the perfomance and effect of proposed circuit and we analyze it`s results by comparing with that of conventional circuit.

새만금 개발과 환경보전

윤경섭,Yoon Kyung-sup 한국관개배수위원회 2000 한국관개배수논문집 Vol.7 No.2

소하천 환경정비 및 수질보전

윤경섭,Yoon Kyung-Sup 한국관개배수위원회 2002 한국관개배수논문집 Vol.9 No.1

농업용 저수지의 수질특성과 수질개선 -왕궁저수지를 대상으로 -

윤경섭 ( Yoon Kyung-sup ),이광식 ( Lee Kwang-sik ),김형중 ( Kim Hyung-joong ),황길순 ( Hwang Gil-son ) 한국농공학회 2002 한국농공학회 학술대회초록집 Vol.2002 No.-

In spite of considerable advances in water quality control measures within lake, many basic questions concerning an eutrophication still remains unanswered and it becomes obvious that an extensive limnological database is needed for the inter-comparison between bodies of water and for the assessment of the status of lake water quality. In order to diagnose the water environment and assess the changes of the water quality, Wangkung irrigation reservoir was investigated by a long-term monitoring program for the physical, chemical and biological water quality parameters. In addition, these data was used to determine the design elements of natural purification facilities.

농업용 저수지의 유형분류 및 수질관리

윤경섭 ( Yoon Kyung Sup ),이광식 ( Lee Kwang Sik ),김형중 ( Kim Hyung Joong ),김호일 ( Kim Ho Il ) 한국농공학회 2003 韓國農工學會誌 : 전원과 자원 Vol.45 No.4

Monitoring data from agricultural reservoirs throughout the country were analyzed to classify agricultural reservoirs according to physical characteristics and COD concentrations, and evaluate the relationships bet-ween water quality items. The physical and chemical data of total 498 reservoirs were analyzed from 1990 to 2001. Average COD, TP, TN, Chl-a, SS concentrations for the reservoirs and pollutant loadings from their watersheds were used for the analysis. It was possible that reservoirs were classified to 4 types using the relationships between the ratios of effective storage per water surface (ST/WS ratio) and COD concentrations. It is recommended that the improvement measures of polluted reservoirs should be performed as following order : integrated consolidation type (complex mechanism type) → watershed consolidation type → integrated consolidation type (external mechanism type) → in-lake consolidation type → conservation type and the depth (ST/WS ratio) of reservoir maintained over 5~6 m for water quality improvement. The decision coefficients (r²) between Chl-a and other items (COD, T-P, SS, T-N) were 0.6915, 0.6732, 0.5327, 0.3352, respectively. Therefore, reservoir managers could evaluate the trophic state of reservoirs by COD concentrations.

영구자석형 교류전동기의 순시전력 제어

尹暻燮(Kyung-Sup Yoon),黃晶煥(Jung-Hwan Hwang),權宇鉉(Woo-Hyen Kwon) 대한전기학회 1997 전기학회논문지 Vol.46 No.8

Poloxamer를 이용한 Swollen Micelle의 Tocopheryl Acetate 안정화

김미선,윤경섭,Kim, Mi-Seon,Yoon, Kyung-Sup 한국응용과학기술학회 2019 한국응용과학기술학회지 Vol.36 No.2

계면활성제가 수용액 중에 용해되면 용액 내에서 micelle (< 20 nm) 이라는 응집체를 형성하며, micelle은 그 내부에 활성물질을 담지하여 가용화 제형이 형성될 수 있다. Swollen micelle은 50~100 nm 정도로 일반 가용화 제형보다 더 많은 양의 활성물질을 담지할 수 있는 제형이다. Swollen micelle은 고압유화와 같은 별도의 공정이 필요한 liposome이나 nanoemulsion과는 달리 특별한 공정이 필요 없어 생산적인 면에서 좀 더 효율성 있는 가용화 및 입자형성 방법이라고 할 수 있다. 본 연구에서는 Poloxamer 407을 이용하여 swollen micelle 제형에 대한 안정화 실험을 진행한 후, Response Surface Methodology (RSM)을 이용하여 tocopheryl acetate 가용화에 대한 제형 최적화 실험을 진행하였다. 가용화에 영향을 주는 계면활성제와 활성물질인 tocopheryl acetate를 요인(factor)로 설정하고 서로 간의 상관관계를 확인하였다. 평가방법으로서 온도 및 시간에 따른 안정성과 입자 분포 및 크기를 확인하였으며, FIB를 통해 효능 물질을 담지한 swollen micelle의 입자 구조 및 모양을 확인하였다. 이러한 실험 결과들을 통하여 tocopheryl acetate를 안정화시킨 swollen micelle은 poloxamer 407 0.500%, octyldodeceth-16 0.387%, tocopheryl acetate 0.945%일 때 가장 최적화된 처방이라 할 수 있다. When the surfactant is dissolved in an aqueous solution, it forms aggregate called micelles (<20 nm) in the solution, and micelles can form the solubilized formulation by supporting the active ingredient therein. Swollen micelles are formulations capable of carrying larger amounts of active ingredient than conventional solubilized formulations at 50~100 nm. Unlike liposomes or nanoemulsions, which require a separate process such as high pressure emulsification, Swollen micelle is a more efficient method of solubilization and particle formation from a productive point of view. In this study, stabilization experiments on swollen micelle formulations were carried out using poloxamer 407, and then optimized formulation experiments for tocopheryl acetate components were performed using Response Surface Methodology (RSM). Tocopheryl acetate, a surfactant that affects solubilization and an active substance, were set as a factor and the correlation between them was confirmed. As the evaluation method, stability and particle size distribution and size were confirmed by temperature and time, and the structure and shape of the swollen micelle carrying the active ingredient were confirmed by FIB. These results show that poloxamer 407 0.500%, octyldodeceth-16 0.387% and tocopheryl acetate 0.945% are the most optimized prescriptions for swollen micelle stabilized with tocopheryl acetate.

삽교호의 수질특성에 관한 연구

김형중,윤경섭,안열,이광식,Kim Hyung Joong,Yoon Kyung Sup,An Yeoul,Lee Kwang Sik 한국관개배수위원회 2004 한국관개배수논문집 Vol.11 No.2

The water quality indexes of Lake Sapkyo in Asan city Korea, were investigated and analyzed to diagnose and assess the water environment. The 55 and T-P concentrations in influent streams were highly variable during the rainstorm event because of the firs

오가피추출물의 멜라닌 생성 저해 효과

임경란 ( Kyung Ran Im ),김미진 ( Mi Jin Kim ),정택규 ( Taek Kyu Jung ),윤경섭 ( Kyung-sup Yoon ) 대한화장품학회 2008 대한화장품학회지 Vol.34 No.2

본 연구에서는 천연 미백소재 개발을 위하여 오가피에서 추출한 페놀산 분획의 멜라닌 생성에 연관된 생리활성을 분석하였다. 오가피에서 추출한 페놀산 분획은 free radical 소거활성(DPPH)에서 IC₅₀ = 3.43 ± 0.35 μg/mL, superoxide radicals 소거활성 IC₅₀ = 158.91 ± 1.57 μg/mL을 나타내었다. B16 melanoma 세포에서의 멜라닌 생합성 저해효과는 농도 의존적으로 저해하여 100 μg/mL에서 27.2 ± 2.65 %의 저해율을 보였다. 그리고 오가피에서 추출한 페놀산 분획은 100 μg/mL에서 세포 내 tyrosinase의 활성을 53.67 ± 8.55 % 저해하였으며, Western blot을 이용하여 tyrosinase와 tyrosinase 관련 단백질(TRP-2)의 발현 감소를 확인하였다. 이러한 결과를 볼 때, 오가피에서 추출한 페놀산 분획은 tyrosinase의 활성 및 발현을 억제함으로써 멜라닌 생성을 감소시키는 것으로 사료된다. 그러므로 오가피에서 추출한 페놀산 분획추출물은 미백용도의 기능성 원료로써 큰 가능성을 가지고 있는 것으로 판단된다. To develop a new natural whitening agent for cosmetics, we investigated effects of Acanthopanax sessiliflorum Seeman on melanogenesis. We prepared phenolic acid-rich extract including two phenolic acids, chlorogenic acid and caffeic acid, as predominant constituents from Acanthopanax sessiliflorum Seeman. Phenolic acid-rich extract showed ROS scavenging activities in 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and xanthine/xanthine oxidase system with the IC₅₀ values of 3.43 ± 0.35 μg/mL and 158.91 ± 1.57 μg/mL, respectively. Phenolic acid-rich fraction reduced melanin contents of B16 melanoma cells dose-dependantly and the decrease was 27.27 ± 2.66 % at a concentration of 100 μg/mL. And the phenolic acid-rich fraction reduced intracellular tyrosinase activity about 53.67 ± 8.55 % at a concentration of 100 μg/mL. Phenolic acid-rich extract inhibited tyrosinase and TRP-2 expression at protein level. These results suggest that phenolic acid-rich fraction reduced melanin formation by the inhibitions of tyrosinase activity and expression in B16 melanoma cells. Therefore, we suggest that phenolic acid-rich extract could be used as a whitening ingredient in cosmetics.

농업용수원인 왕궁저수지의 수질특성

김형중,윤경섭,이광식,Kim Hyung-Joong,Yoon Kyung- Sup,Lee Kwang- Sik 한국관개배수위원회 2003 한국관개배수논문집 Vol.10 No.2

Physical, chemical and biological water quality indexes of Wanggung agricultural reservoir in Iksan city Korea, were investigated and analyzed to diagnose and assess the water environment from 2000 to 2002. The mean concentrations of SS, COD and T-P satis