• Title/Summary/Keyword: FLS

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Unveiling the Lens Galaxy of FLS 1718+59: A Galaxy-Galaxy Gravitational Lens System

  • Taak, Yoon Chan;Im, Myungshin
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.2
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    • pp.70.1-70.1
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    • 2014
  • We analyze a newly discovered galaxy-galaxy scale gravitational lens system, FLS 1718+59 in the Spitzer First Look Survey (FLS) field. A background galaxy (z = 0.245) is severely distorted by a foreground galaxy (z = 0.08), via gravitational lensing. We analyze this system by several methods, including surface brightness fitting (Galfit and Ellipse), gravitational lens modeling (gravlens), and spectral energy distribution fitting (Magphys). From Galfit and Ellipse we measure properties of the lens galaxy, such as the effective radius and the average surface brightness inside it, the ellipticity, and the position angle. gravlens gives us the total mass inside the Einstein radius ($R_{Ein}$), and Magphys provides us an estimate of the stellar mass inside $R_{Ein}$. By comparing these obtained parameters, we confirm that the lens galaxy is an elliptical galaxy on the Fundamental Plane, and calculate the stellar mass function inside $R_{Ein}$, and discuss the implications of the results regarding the initial mass function.

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Inhibitory Effects of Gamimahaenggamsuk-tang on RA-related Inflammatory Responses in Cultured Fibroblast-like Synoviocytes

  • Jo Jun;NamGung Uk;Kim Soo-Myung;Kang Tak-Lim;Kim Dong-Hee
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.19 no.6
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    • pp.1647-1655
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    • 2005
  • Gamimahaenggamsuk-tang (GMHGST) is used for treatment of inflammatory diseases including rheumatoid arthritis (RA). Here, regulatory activity of GMHGST on RA-mediated inflammatory responses was investigated in cultured human fiDroblast-like synoviocytes (FLS), Levels of mRNAs encoding for inflammatory cytokines such as $IL-1{\beta}$, IL-6 and IL-8 and NOS-II enzyme, which had been induced by $TNF-{\alpha}$ and $IL-1{\beta}$ cotreatment, were decreased to the similar levels as those in cells treated with anti-inflammatory agent MTX. mRNA expressions of matrix metalloproteinase-3 (MMP-3) and tissue inhibitor of metalloproteinases (TIMPs) as well as intercellular adhesion molecule (ICAM) were also downregulated by increasing doses of GMHGST in activated FLS. Moreover, GMHGST appeared to protect cells by decreasing NO levels, and inhibited cell proliferation which had been induced by inflammatory stimulation by $TNF-{\alpha}$ and IL-1. These results suggest that GMHGST is effective as an inhibitory agent for regulating inflammatory responses in activated FLS.

Phytoceramide Alleviates the Carrageenan/Kaolin-Induced Arthritic Symptoms by Modulation of Inflammation

  • Bongjun Sur;Mijin Kim; Thea Villa;Seikwan Oh
    • Biomolecules & Therapeutics
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    • v.31 no.5
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    • pp.536-543
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    • 2023
  • Phytoceramide (Pcer) is found mainly in plants and yeast. It can be neuroprotective and immunostimulatory on various cell types. In this study, the therapeutic effect of Pcer was explored using the carrageenan/kaolin (C/K)-induced arthritis rat model and fibroblast-like synoviocytes (FLS). Pcer treatment (1, 10, and 30 mg/kg/day) were given to the arthritic rats for 6 days after disease induction. Weight distribution ration (WDR), knee thickness, squeaking score, serum levels of proinflammatory mediators, and histological analysis were measured and performed to evaluate arthritic symptoms in the rat model. In interleukin (IL)-1β-stimulated FLS, proinflammatory mediators were measured after Pcer (1-30 µM) treatment. Arthritic symptoms in rats with Pcer treatment were significantly decreased at days 4 to 6 after C/K arthritis induction. Inflammation in the knee joints were also significantly decreased in rats with Pcer treatment. Furthermore, in IL-1β-stimulated FLS, the expressions of proinflammatory mediators were also inhibited by Pcer. As shown by the results, Pcer has anti-arthritic effects in the C/K rat model and in synovial cells, suggesting that Pcer has the potential to be a useful agent in arthritis treatment.

Role of Immune Response to Type II Collagen in the Pathogenesis of Rheumatoid Arthritis (류마티스 관절염 병인에서 제2형 콜라겐에 대한 면역반응의 역할)

  • Jung, Young Ok;Hong, Seung-Jae;Kim, Ho-Youn
    • IMMUNE NETWORK
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    • v.3 no.1
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    • pp.1-7
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    • 2003
  • Type II collagen (CII), major component of hyaline cartilage, has been considered as an auto-antigen in rheumatoid arthritis (RA). However, the clinical and biological significances with regard to the CII autoimmunity need to be clarified in human RA. The presence of antibodies to CII has been identified in sera, synovial fluid, and cartilage of patients with RA. In our study, the increased titer of IgG anti-CII in sera was well correlated with C-reactive protein, suggesting that this antibody may reflect the inflammatory status of RA. The titer of anti-CII antibodies (anti-CII Abs) tended to be higher in early stages of diseases. In our extending study, among 997 patients with RA, 269 (27.0%) were positive for circulatory IgG antibody to CII, those levels were fluctuated over time. It is hard to assess the significant amount of T cell responses to CII and CII (255~274) in RA. By using a sensitive method of antigen specific mixed lymphocyte culture, we can detect the presence of CII-reactive T cells in peripheral blood mononuclear cells of RA patients. Sixty seven (46.9%) of 143 patients showed positive CII reactive T cell responses to CII or CII (255~274). The frequencies of CII reactive T cells were more prominent in inflamed synovial fluid (SF) than in peripheral blood. These T cells could be clonally expanded after consecutive stimulation of CII with feeding of autologous irradiated antigen presenting cells (APC). Moreover, the production of Th1-related cytokine, such as IFN-${\gamma}$, was strongly up-regulated by CII reactive T cells. These data suggest that T cells responding to CII, which are probably presenting the IFN-${\gamma}$ producing cells, may play an important role in the perpetuation of inflammatory process in RA. To evaluate the effector function of CII reactive T cells, we investigated the effect of CII reactive T cells and fibroblasts-like synoviocytes (FLS) interaction on the production of pro-inflammatory cytokines. When the CII reactive T cells were co-cultured with FLS, the production of IL-15 and TNF-${\alpha}$ from FLS were significantly increased (2 to 3 fold increase) and this increase was clearly presented in accord to the expansion of CII reactive T cells. In addition, the production of IFN-${\gamma}$ and IL-17, T cell derived cytokines, were also increased by the co-incubation of CII reactive T cells with FLS. We also examined the impact of CII reactive T cells on chemokines production. When FLS were co-cultured with CII stimulated T cells, the production of IL-8, MCP-1, and MIP-1${\alpha}$ were significantly enhanced. The increased production of these chemokines was strongly correlated with increase the frequency of CII reactive T cells. Conclusively, immune response to CII was frequently found in RA. Activated T cells in response to CII contributed to increase the production of proinflammatory cytokines and chemokines, which were critical for inflammatory responses in RA. The interaction of CII-reactive T cells with FLS further augmented this phenomenon. Taken together, our recent studies have suggested that autoimmunity to CII could play a crucial role not only in the initiation but amplification/perpetuation of inflammatory process in human RA.

Effect of Preparation method and Fermentation Conditions on Microbiological Characteristics of Sikhae (어류를 이용한 식해의 제조 방법에 따른 미생물의 특성변화)

  • Kim, Young-Sook;Oh, Seung-Hee;Kim, Soon-Dong
    • Food Science and Preservation
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    • v.15 no.6
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    • pp.909-914
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    • 2008
  • This study investigated microbial populations and the sensory quality of sikhae including globefish (GLS), flounder (FLS), gastropods (GAS) and whelks (WHS) during storage at 4C for 16 d following fermentation at 10C for 4 d. General bacterial numbers increased to 102 in GLS and FLS, and to 1045 in WHS and GAS after the 20 d fermentation/storage period. Lactic acid bacteria increased to 108 log cycle in GLS and FLS after 10 d ripening time, and reached this level in GAS and WHS after 15 d and 20 d, respectively. After 20 days the number of lactic acid bacteria in each of the four samples was 108. There were 104105 yeast cells/g in each of the four samples after 20 d. The number of Leuconostoc increased to over 108 log cycle after 10 d in GLS and FLS, and 15 days in GAS for WHS the increase was to 107 log cycle. The pH values of GLS, FLS, GAS and WHS 4.42, 4.56, 4.31 and pH 4.26, respectively. The Sikhae acidity for all four samples ranged from 1.551.85%. From the sensory evaluation the overall acceptability was in the order of FLS > GLS > GAS > WHS.

Modeling and Performance Analysis of Non-linear System Using Type-2 Fuzzy Logic Systems (Type-2 Fuzzy Logic System을 이용한 비선형 시스템의 모델링 및 성능 분석)

  • 안성배;김동원;박귀태
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2003.09b
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    • pp.76-79
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    • 2003
  • 퍼지 로직 시스템(FLS)은 다양한 분야에서 성공적으로 사용되고 있다 퍼지 로직 시스템의 멤버십 함수와 규칙은 언어적인 정보나 수치적 데이터를 사용하여 표현된다. 또한 이러한 정보나 데이터에는 불확실성과 노이즈 등이 존재한다. 그러나 단순한 퍼지 로직 시스템으로노이즈가 포함된 불확실한 정보를 효과적으로 다루고 표현하는 데는 한계가 있다. 그러므로 노이즈가 포함된 정보를 효율적으로 처리하기 위해 본 논문에서는 type-2 FLS를 이용한다. 노이즈가 포함되어 불확실한 정도를 정확한 값으로 표현하기 어려울 때, type-2 FLS은 보다 정확하게 정보들을 다를 수 있음을 보인다. 비선형 시계열 시스템인 Box-Jenkins 데이터를 이용하여 singleton Type-1 FLS과 non-singleton type-1 FLS의 결과 값을 확인하고 이의 성능을 type-2 FLS과 비교, 분석한다.

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An Approach to Noble Design of Type-2 TSK Fuzzy Logic System (Type-2 TSK 퍼지 논리 시스템의 새로운 설계에 대한 접근)

  • Kim, Woong-Ki;Oh, Sung-Kwun
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.1845-1846
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    • 2008
  • Type-2 퍼지 집합은 언어의 불확실성을 다루기 위하여 고안된 Type-1 퍼지집합의 확장이다. TSK 퍼지 로직 시스템(TSK Fuzzy Logic Systems; TSK FLS)은 Mamdani FLS과 함께 가장 널리 사용되는 퍼지 로직 시스템 모델이다. 본 논문에서는 Type-2 퍼지 집합을 이용하여 전반부 멤버쉽 함수를 구성하고 후반부 다항식 함수를 상수와 1차식, 2차식으로 확장한 다항식 Type-2 TSK FLS 설계한다. 다항식 Type-2 TSK FLS의 파라미터를 동정하기 위해 Back-propagation 방법을 사용한다. 제안된 다항식 Type-2 TSK FLS을 노이즈 섞인 비선형 시스템의 모델링에 적용하여 그 성능을 비교 분석한다.

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Model Following Adaptive Controller with Rotor Resistance Estimator for Induction Motor Servo Drives (회전자 저항 추정기를 가지는 유동전동기 구동용 모델추종 적응제어기 설계)

  • Kim, Snag-Min;Han, Woo-Yong;Lee, Chang-Goo
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.2
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    • pp.125-130
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    • 2001
  • This paper presents an indirect field-oriented (IFO) induction motor position servo drives which uses the model following adaptive controller with the artificial neural network(ANN)-based rotor resistance estimator. The model reference adaptive system(MRAS)-based 2-layer ANN estimates the rotor resistance on-line and a linear model-following position controller is designed by using the estimated the rotor resistance value. At the end, a fuzzy logic system(FLS) is added to make the position controller robust to the external disturbances and the parameter variations. The simulation results show the effectiveness of the proposed method.

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Design of Type-2 Fuzzy Logic Systems Using Genetic Algorithms (유전자 알고리즘을 이용한 타입-2 퍼지논리시스템의 설계)

  • 박세환;이광형
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2000.05a
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    • pp.220-223
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    • 2000
  • 타입-2 퍼지집합을 이용하여 퍼지논리시스템(Fuzzy Logic System : FLS)을 구현하기 위한 연구들이 R. I John, N. Karnik, J. Mendel 등에 의해 현재 진행되고 있다. 타입-2 집합을 이용한 타입-2 FLS은 기존의 타입-1 FLS보다 제어규칙이나 소속함순가 가지고 있는 불확실성을 표현하는데 있어서 더 효과적이다. 그러나, 타입-2 FLS 역시 타입-1 FLS이 가지고 있는 문제점인 설계시 전문가에게 의존하여 시간과 비용이 많이 소요되고, 제어기의 구성요소들을 효율적으로 생성하기가 어렵다는 문제점을 더욱 심각하게 가지고 있다. 또한, 그 문제점을 해결하기 위한 연구들도 아직 미진한 상태이다. 본 논문에서는 타입-2 FLS의 설계를 위해 유전자 알고리즘을 사용하는 방법을 제안한다. 타입-2 FLS를 설계하기 위해서는 소속함수와 제어규칙을 생성하여야 한다. 본 논문에서는 유전자 알고리즘을 사용하여 타입-2 퍼지제어규칙과 소속함수를 설계하는 방법을 제안한다. 먼저, 유전자 알고리즘에서 사용할 수 있는 유전자의 형태로 타입-2 퍼지제어규칙과 소속함수를 표현하기 위한 인코딩방법을 제안하고, 각각의 염색체를 진화시키기 위한 교차 연산자와 돌연변이 연산자를 정의한다. 그리고, 제안된 방법을 함수근사문제에 적용하여 유효성과 성능을 평가, 검증한다.

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