N/O/N 박막 다이아프레임을 이용한 광섬유 압력센서의 제작 및 그 압력특성

유양욱,김명규,박동수,김창원,김진섭,이정희,손병기 경북대학교 센서기술연구소 1995 센서技術學術大會論文集 Vol.6 No.1

The 0.6 μm N/O/N triple layer, Si_(3)N_(4)(150 nm)/SiO_(2)(300 nm)/Si_(3)N_(4)(150 nm), was deposited on silicon substrate and the N/O/N thin film diaphragm was formed using anisotropic etching technique. The stress of the formed diaphragm was very small with temperature variations. Combining this diaphragm and the optical fiber, intensity-type pressure sensor was fabricated and its pressure characteristics were investigated. The relation between the optical output power, inversely proportional to the deflection of the diaphragm, and the applied pressure was almost linear in 0~77 torr range.

스크러버형 EGR시스템 디젤기관의 배기 배출물에 미치는 재순환 배기온도의 영향

배명환,류창성 경상대학교 생산기술연구소 2002 工學硏究院論文集 Vol.2 No.-

The effects of intake mixture temperature on performance and exhaust emissions under four kinds of engine loads were experimentally investigated by using a four-cycle four-cylinder, swirl chamber type, water-cooled diesel engine with scrubber EGR system operating at three kinds of engine speeds. The purpose of this study is to develop the scrubber exhaust gas recirculation(EGR) control system for reducing NO_x and soot emissions simultaneously in diesel engines. The EGR system is used to reduce NO_x emissions. And a novel diesel soot-removal device with a cylinder-type scrubber which has five water injection nozzles is specially designed and manufactured to reduce soot contents in the recirculated exhaust gas to the intake system of the engine. The influences of cooled EGR and water injection, however, would be included within those of scrubber EGR system. In order to study the effect of intake mixture temperature, a intake mixture heating device which has five heating coils is made of a steel drum. It is found that the specific fuel consumption rate is considerably elevated by the increase of intake mixture temperature, and that NO_x emissions are markedly decreased as EGR rates are increased and intake mixture temperature is dropped, while soot emissions are increased with increasing EGR rates and intake mixture temperature.

CFCM 기반 적응 뉴로-퍼지 시스템에 의한 비선형 시스템 모델링

곽근창,김성수,유정웅,전명근 충북대학교 컴퓨터정보통신 연구소 2002 컴퓨터정보통신연구 Vol.10 No.2

본 논문에서는 여러 분야에서 널리 응용되고 있는 적응 뉴로-퍼지 시스템에서의 효과적인 퍼지 규칙 생성 방법을 제안한다. 기존의 입력공간 그리드 분할을 이용한 ANFIS의 규칙 생성에 있어서는 얻어진 규칙의 수가 지수적으로 증가하는 단점이 있다. 이에, 본 연구에서는 조건부적인 퍼지 클러스터링(CFCM)을 이용하여 입·출력 데이터의 특성을 잘 반영할 수 있는 클러스터를 구하고, 퍼지 균등화 방법을 적용하여 출력변수의 소속함수를 자동 생성하도록 하였다. 이렇게 함으로써 적은 규칙 수를 갖으면서도 효율적인 퍼지 규칙을 얻을 수 있도록 하였다. 이들 방법의 유용함을 보이고자 정수장 응집제주입결정 모델링에 적용하여 제안된 방법이 기존의 연구보다 좋은 결과를 보임을 알 수 있었다. In this paper, an efficient fuzzy rule generation scheme for Adaptive Network-based Fuzzy Inference System(ANFIS) using the conditional fuzzy c-means(CFCM) and fuzzy equalization(FE) methods is proposed. Usually, the number of fuzzy rules exponentially increases by applying the grid partitioning of the input space, in conventional ANFIS approaches. Therefore, GFCM clustering method is adopted to render the clusters which represent the given input and output fuzzy data and FE method is used to automatically construct the fuzzy membership functions. From this, one can systematically obtain a small size of fuzzy rules which shows satisfying performance for the given problems. Finally, we applied the proposed method to the nonlinear system modeling problems and obtained a better performance than conventional works.

유전체 충전형 플라즈마 반응기를 이용한 Trichloroethylene의 분해반응

이해완,류삼곤,박명규,박현배,황경창 한국화학공학회 2003 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.41 No.3

유전체 충전형 플라즈마 반응기를 이용하여 공기중 trichloroethylene (TCE)의 분해반응에 대한 연구를 수행하였다. 방전전력, 체류시간 및 반응물 유입농도 등과 같은 여러 가지 운전변수에 따른 TCE의분해효율을 조사하고, 반응 부산물의 분석을 통하여 TCE 분해 반응 메커니즘을 제시하였다. 실험결과 방전전력 및 체류시간이 증가함에 따라 TCE 분해효율은 증가하였으나 유입농도의 변화에 대한 영향은 거의 없었다. BaTiO_3를 충전한 반응기가 알루미나를 충전한 반응기보다 분해효율이 높았으나 TCE의 완전 산화분해의척도가 되는 CO_x(CO+CO_2)의 수율 및 CO_2의 선택도는 BaTiO_3를 충전한 반응기보다 알루미나를 충전한 반응기가 월등하게 높았다. 반응생성물 분석결과 주반응 생성물은 CO_x,CHCl_2COCl, C_2H_2Cl_2O_2및 COCl_2로 공기중 TCE의 분해 메커니즘은 주로 ClO와 OH 라디칼에 의한 반응으로 판단된다. The decompositon of trichloroethylene (TCE) in air using a ferroelectric packed-bed reactor was studied. The effects of discharge power, residence time, inlet concentration and other operating conditions on the decomposition efficiency were investigated and the analysis of reaction products was conducted to suggest the mechanism of TCE decomposition. Experimental results showed that the decomposition efficiency of TCE increased with increasing discharge power and residence time but was unaffected by inlet concentration. The decomposition efficiency for BaTiO_3 packed reactor was higher than that for alumina packed reactor, but the yield of CO_x(CO+CO_2) and selectivity of CO_2 as the measure of the complete oxidation of TCE were higher in alumina packed reactor. The main products of TCE decomposition were CO_x,CHCl_2COCl, C_2H_2Cl_2O_2 and COCl_2. On the basis of the results, it is inferred that the decomposition of TCE in air proceeds by OH and CIO radical reaction mechanism.

LY6D is crucial for lipid accumulation and inflammation in nonalcoholic fatty liver disease

Lee Jibeom,Kim Hyeonhui,Kang Yun-Won,Kim Yumin,Park Moon-young,Song Ji-Hong,Jo Yunju,Dao Tam,Ryu Dongryeol,Lee Junguee,Oh Chang-Myung,Park Sangkyu 생화학분자생물학회 2023 Experimental and molecular medicine Vol.55 No.-

Nonalcoholic fatty liver disease (NAFLD) is a serious metabolic disorder characterized by excess fat accumulation in the liver. Over the past decade, NAFLD prevalence and incidence have risen globally. There are currently no effective licensed drugs for its treatment. Thus, further study is required to identify new targets for NAFLD prevention and treatment. In this study, we fed C57BL6/J mice one of three diets, a standard chow diet, high-sucrose diet, or high-fat diet, and then characterized them. The mice fed a high-sucrose diet had more severely compacted macrovesicular and microvesicular lipid droplets than those in the other groups. Mouse liver transcriptome analysis identified lymphocyte antigen 6 family member D (Ly6d) as a key regulator of hepatic steatosis and the inflammatory response. Data from the Genotype-Tissue Expression project database showed that individuals with high liver Ly6d expression had more severe NAFLD histology than those with low liver Ly6d expression. In AML12 mouse hepatocytes, Ly6d overexpression increased lipid accumulation, while Ly6d knockdown decreased lipid accumulation. Inhibition of Ly6d ameliorated hepatic steatosis in a diet-induced NAFLD mouse model. Western blot analysis showed that Ly6d phosphorylated and activated ATP citrate lyase, which is a key enzyme in de novo lipogenesis. In addition, RNA- and ATAC-sequencing analyses revealed that Ly6d drives NAFLD progression by causing genetic and epigenetic changes. In conclusion, Ly6d is responsible for the regulation of lipid metabolism, and inhibiting Ly6d can prevent diet-induced steatosis in the liver. These findings highlight Ly6d as a novel therapeutic target for NAFLD.

Carcinoembryonic Antigen in Patients with Cervical Carcinoma

Choi, Myung Sun,Park, Chang Yoon,Ryu, Kyungza Yonsei University, College of Medicine 1977 Yonsei medical journal Vol.18 No.1

무인기 자율항법 검증을 위한 통합시험환경 TCAS 모델 설계

류창명(Chang Myung Ryu),조영우(YoungWo Jo),이성우(SeongWoo Lee) 한국항공우주학회 2019 한국항공우주학회 학술발표회 논문집 Vol.2019 No.4

운동강도와 지속시간에 따른 트레드밀 운동이 비만 쥐의 심장근 내 항산화에 미치는 영향

김명희,김용억,윤창륙,유지원,안종모,Kim, Myung-Hee,Kim, Young-Eok,Yoon, Chang-Lyuk,Ryu, Ji-Won,Ahn, Jong-Mo 대한안면통증구강내과학회 2013 Journal of Oral Medicine and Pain Vol.38 No.1

트레드밀 운동이 비만 쥐의 심장근 내 항산화에 어떠한 영향을 주는지 알아보고자 흰쥐에 6주 동안 고지방 식이로 비만을 유발시킨 뒤 운동강도와 적용시간을 달리하여 트레드밀을 3주 동안 적용하였으며, 체중변화, 혈중지질성분, 조직학적 변화, 심장근 내 항산화 효소와 MCP-1(monocyte chemoattractant protein-1) 등의 변화를 연구하였다. 4주령 Sprague Dawley계 수컷 흰쥐 32마리를 사용하여 각각 일반사료를 섭취한 정상군 (normal), 비만 대조군 (control), 비만 쥐에게 고강도 분할운동을 적용한 실험군 I(Experimental I), 비만 쥐에게 중강도 지구력 운동을 적용한 실험군 II (Experimental II)로 나누었다. 실험 결과 첫째, 체중변화는 고강도 분할 운동을 적용한 실험군 I과 중강도 지구력 운동을 적용한 실험군 II는 대조군에 비해 유의한 감소가 있었다 (p<0.001). 특히, 운동을 적용한 1주에서 3주까지 유의한 차이가 있었다. 둘째, 혈중지질성분 수치는 고강도 분할 운동을 적용한 실험군 I과 중강도 지구력 운동을 적용한 실험군 II는 대조군에 비해 총콜레스테롤, 중성지방, 저밀도 지단백질의 유의한 감소, 고밀도 지단백질에서는 유의한 증가가 있었다 (p<0.001). 셋째, 심장근의 조직학적 소견은 심장근에서 아교질 형성과 평활근 섬유의 정렬 상태와 밀집도, 심장근 세포크기가 중강도 지구력 운동 적용한 실험군 II에서 정상군과 비슷한 형태인 근육들이 잘 밀집해 있는 것을 볼 수 있었다. 또한, 섬유아세포, 염증세포들의 침윤 등이 고지방 식이 유발 쥐인 대조군과 고강도 분할 운동을 적용한 실험군 I에서 가장 심하였으며, 중강도 지구력 운동을 적용한 실험군 II는 대조군에 비해 섬유아세포, 염증세포들의 침윤 등이 현저히 감소하였다. 넷째, 심장근의 항산화 효소 SOD(superoxide dismutase), CAT(catalase), GPx(glutathione peroxidase) 수치는 중강도 지구력 운동을 적용한 실험군 II와 고강도 분할 운동을 적용한 실험군 I에서 모두 유의한 증가가 있었다 (p<0.001). 다섯째, 심장근의 항산화 단백질 MCP-1 발현 수치는 고강도 분할 운동을 적용한 실험군 I과 중강도 지구력 운동을 적용한 실험군 II 모두에서 감소가 있었으며 (p<0.01), 특히, 중강도 지구력 운동을 적용한 실험군 II에서는 유의한 감소가 있었다 (p<0.001). 따라서, 중강도 지구력 운동은 고지방 식이로 유발된 비만 쥐의 심장근 내 항산화에 영향을 주어 비만 개선과 산화적 스트레스에 의한 심장근육 손상 감소 등에 효과적인 것으로 나타났다. The aims of this study was to observed an effect of antioxidative in cardiac muscle of high fat diet induced obesity rat by treadmill exercise with intensity and time. Thirty-two Sprauge-Dawley rats which were divided into four group. Normal, Control(high fat diet induced obesity rat), Experimental I(high intensity intermittent exercise in high fat diet induced obesity rat), Experimental II(moderate intensity endurance exercise in high fat diet induced obesity rat). The results of this study were as follows: 1. In change of body weight, the outcome of each group significantly difference compared with control. Also, 1 to 3 weeks significantly different compared with pre valu experimental I and II(p<0.001). 2. In change of lipid profile, the outcome of each group significantly difference compared with control(p<0.001). Difference between experimental I and II is not significantly. 3. In change of antioxidative enzymes(SOD, CAT, GPx) in myocardium, there are significant difference between control and experimental II, and also between control and experimental I(p<0.001). 4. In change of antioxidative protein MCR-1, the outcome of each group significantly difference compared with control(p<0.01). Experimental II was most significantly difference than the other group(p<0.001). The above results suggest that treadmill exercise effectively reduced in fat. It would be considered that moderate intensity endurance exercise has an effects on improved antioxidative enzyme in cardiac muscle of high fat diet induced obesity rat.

Cu²⁺-selective fluorescent probe based on the hydrolysis of semicarbazide derivative of 2-(2-aminophenyl)benzothiazole

Ryu, Hyein,Choi, Myung Gil,Cho, Eun Jin,Chang, Suk-Kyu Elsevier 2018 Dyes and pigments Vol.149 No.-

<P><B>Abstract</B></P> <P>A new Cu<SUP>2+</SUP>-selective reaction-based fluorescent probe <B>1</B> based on the semicarbazide-bearing derivative of 2-(2-aminophenyl)benzothiazole has been developed. Designed probe <B>1</B> exhibited turn-on-type fluorescence signaling behavior that was more prominent toward Cu<SUP>2+</SUP> ions than to other environmentally relevant metal ions. The signaling of probe <B>1</B> was due to the Cu<SUP>2+</SUP>-induced hydrolysis of semicarbazide moiety to form its strongly fluorescent parent dye. Cu<SUP>2+</SUP> signaling of probe <B>1</B> was not influenced by the presence of commonly encountered metal ions, and the detection limit was 1.71 × 10<SUP>−8</SUP> M (1.1 ppb). As a practical application, the determination of Cu<SUP>2+</SUP> in simulated semiconductor wastewater was conducted using a smartphone as a portable signal detection tool. For the color test analysis, enhanced reproducibility of Cu<SUP>2+</SUP>-sensing was realized using the grayscale image rather than the red, green, or blue channel image.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Cu<SUP>2+</SUP>-selective probe with semicarbazide moiety as a signaling switch was developed. </LI> <LI> Fluorogenic Cu<SUP>2+</SUP> signaling was based on hydrolysis of semicarbazide moiety. </LI> <LI> Cu<SUP>2+</SUP>-sensing over other metal ions was possible, with a detection limit of 17 nM. </LI> <LI> The probe determined Cu<SUP>2+</SUP> level in semiconductor wastewater using a smartphone. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Microporous Porphyrin Networks Mimicking a Velvet Worm Surface and Their Enhanced Sensitivities toward Hydrogen Chloride and Ammonia

Ryu, Sang Hyun,Kang, Chang Wan,Choi, Jaewon,Myung, Yoon,Ko, Yoon-Joo,Lee, Sang Moon,Kim, Hae Jin,Son, Seung Uk American Chemical Society 2018 ACS APPLIED MATERIALS & INTERFACES Vol.10 No.8

<P>This work shows that the functions of microporous organic network materials can be enhanced through engineering of the material structure. Mimicking the surface structure of velvet worms, we prepared the aligned 1D structure (rod) of microporous porphyrin networks by the Sonogashira coupling of tetrakis(4-ethynylphenyl)porphyrin with 1,4-diiodobenzene in an anodic aluminum oxide plate. The length of the 1D structure was controlled in the range of 1-5 mu m. The velvet worm surface-like microporous porphyrin networks (Velvet-MPNs) showed higher sensitivities to hydrogen chloride and ammonia gases by up to similar to 14 and 4.6 times, respectively, compared with a control MPN material without rods.</P>