• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.1970-1972
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• 2001

This paper is concerned with the $H_{\infty}$ controller design of linear systems subject to time-delay in the state and saturating controls. The controller is derived from the matrix inequalities whish are obtained by minimizing the $L_{2}$ gain from the disturbance to the measured output, and this can be done by LMI control toolbox. An example is presented to show the usefulness of our result.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.1
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• pp.50-53
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• 2007

To develope skin-whitening or therapeutic agents against hyperpigmentation, aqueous extract from Amomum xanthioides (AEAX) was evaluated for melanogenesis inhibitory activity in B16F10 melanoma cell. The treatment with AEAX at the 0.5 and 1.0 mg/ml level significantly inhibits the biosynthesis of melanin compared with untreated control. The AEAX-treated cells at the 1.0 mg/ml level were more efficient than commercial arbutin at 0.1 mg/ml. The tyrosinase activity also significantly decreased in AEAX-treated cells at the 0.5 and 1.0 mg/ml level. The Western analyses confirmed the significantly decreased expression of tyrosinase and tyrosinase-related protein-1 by AEAX treatment. These results indicate that AEAX may contribute to the inhibition of melanin biosynthesis through regulating tyrosinase activity and expression and serve as a new candidate in the design of new skin-whitening or therapeutic agents.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.3
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• pp.27-36
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• 2022

Purpose : This study was aimed to analyze the effects of cosmetics containing Persicaria perfoliata water extract (PPWE) on the skin moisturizing and improvement of skin condition in clinical trials. Methods : Clinical trial was conducted for five weeks after IRB approval at Dong-Eui University. Out of a total of 64 people, 15 people each were assigned to four groups as follows; control group A, B, C and the experimental group A that using cosmetic containing PPWE. Skin condition was measured two times, before and after clinical trial, by a professional skin analyzer, SDM (skin diagnosis system). Moisture and oil value of participants was analyzed twice, each morning and evening, using a portable device on their cheeks. In addition, the survey was investigated subjective satisfaction on change in skin condition and the satisfaction on the use of cosmetics. Result : The experimental group exhibited subjectively significant changes before and after clinical trials on skin its dryness (p=.039), blush (p=.017), and redness (p<.001). In addition, subjective evaluation was also the highest satisfaction in aspects of number of application (p=.003), amount of application (p=.002), moisture maintenance, and skin scratching frequency. The satisfaction on the use of cosmetics was the highest in the intention to repurchase (p=.045), recommendation willingness to others (p=.020), and intention to use various products (p=.001). Skin moisture of the clinical trial participants using the SDM, moisture level and elasticity of the experimental group increased by 12.94 and 10.28. Moisture level, which was measured by a portable device, was the most potently increased in the experimental group. Conclusion : Consequently, PPWE containg cosmetics exhibited the effects of moisturization and attenuated skin dryness in clinical trials, which might be utilized as a fundamental data to develop numerous lines of cosmetics.

• Journal of Life Science
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• v.19 no.2
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• pp.249-255
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• 2009

Esculetin, a coumarin compound, has been known to inhibit proliferation and induce apoptosis in several types of human cancer cells. However, the molecular mechanisms involved in esculetin-induced apoptosis are still uncharacterized in human leukemia cells. In this study, we have investigated whether esculetin exerts anti-proliferative and apoptotic effects on human leukemia U937 cells. It was found that esculetin could inhibit cell viability in a time-dependent manner, which was associated with the induction of apoptotic cell death such as increased populations of apoptotic- sub G1 phase. Apoptosis of U937 cells by esculetin was associated with an inhibition of Bcl-2/Bax binding activity, formation of tBid, down-regulation of X-linked inhibitor of apoptotic protein (XIAP) expression, and up-regulation of death receptor 4 (DR4) and FasL expression. Esculetin treatment also induced the degradation of ${\beta}$-catenin and DNA fragmentation factor 45/inhibitor of caspase-activated DNase (DFF45/ICAD). Furthermore, a caspase-3 specific inhibitor, z-DEVD-fmk, significantly inhibited sub-G1 phase DNA content, morphological changes and degradation of ${\beta}$-catenin and DEE45/ICAD. These results indicated that a key regulator in esculetin-induced apoptosis was caspase-3 in human leukemia U937 cells.

• Journal of Life Science
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• v.24 no.1
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• pp.61-66
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• 2014

The purpose of this study was to investigate the immunomodulatory effects of Alpina officinarum (AO) ethanol extract on immunocompromised mice. The mice were injected intraperitoneally with an immunosuppressive drug, cyclophosphamide, and then administrated orally with 30, 100, and 300 mg/kg of ethanol extract of AO (AO 30, AO 100, and AO 300, respectively). The concentrations of cytokines and immunoglobulins (IgM, IgA, IgG) in serum were measured. The body weight of the mice and spleen cell number of the AO-fed group showed no significant difference compared to a control group. The concentrations of several cytokines, including IL-2, IFN-${\gamma}$, and TGF-${\beta}$, in serum showed a significant increase in the AO 100 group compared to the control and other groups (p<0.05). The IL-4 level showed no significant difference in the experimental groups. The supplementation of AO (30, 100, 300 mg/kg) significantly increased the concentration of IgM (p<0.05). The concentration of IgA was significantly increased in the AO 100 group (p<0.05) compared to the control group. It can be concluded that AO ethanol extract enhances immune function by promoting the production of cytokines and immunoglobulins.

• International Journal of Human Ecology
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• v.15 no.1
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• pp.12-22
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• 2014

The effects of conflicted teacher-child relation on conflicted or passive peer interaction and a moderation effect of mothers' interpersonal relation satisfaction on the associations were assessed. Children from 2- to 6-year-olds (184 girls, 185 boys) mostly from middle socioeconomic-status urban community in Korea and their teachers and mothers participated. Conflicted teacher-child relation predicted conflicted peer interaction but not passive peer interaction. Children, whose relationship with teachers were conflicted, engaged in conflicted play with peers more often than children who were in less conflicted relationship with the teachers. Teachers who were in conflicted relationship with the children, perceived the children having conflicted interaction with peers more often, if mothers of the children were less satisfying in relationship with significant others, especially boys. Children, whose mothers are in less satisfying interpersonal relation with others, were more passive in peer interaction than children whose mothers are in more satisfying interpersonal relationship.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.271.3-272
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• 2002

This study shows that sphingosine-1-phosphate (SPP) significantly inhibits melanin synthesis in a concentration-dependent manner, and that the activity of tyrosinase was also reduced in SPP-treated cells. In contrast. a specific extracellular signal-regulated protein kinase (ERK) pathway inhibitor, PD98059 increased tyrosinase activity and melanin production, and PD98059 restored the reduced tyrosinase activity and pigmentation induced by SPP. (omitted)

• Annual Conference on Human and Language Technology
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• 2002.10e
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• pp.111-117
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• 2002

개체명 인식은 질의응답(QA), 정보 주줄(IE), 텍스트 마이닝 시스템의 성능 향상에 중요한 역할을 담당한다. 이 논문에서는 교사학습 기반의 한국어 개체명 인식에 대해 설명한다. 한국어에서 많은 개체명들이 하나 이상의 단어로 구성되어 있으며, 개체명을 구성하는 단어 사이에는 의존 관계가 존재하고, 개체명과 개체명 주위의 단어 사이에도 문맥적 의존관계를 가지고 있다. 본 논문에서는 가변길이의 개체명과 주변 문맥의 학습을 위해 트라이그램을 이용한 HMM을 사용하였으며, 자료 부족 문제를 해소하기 위해 어휘 기반이 아닌 부개체 유형 기반의 학습을 수행하였다. 학습된 개체명 인식 시스템을 이용하여 경제 분야의 신문 기사에 대한 실험 결과, 84.4%의 정확률과 90.9%의 재현률을 보였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11a
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• pp.597-600
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• 2002

본 논문에서는 정보추출 및 정보검색, 문서요약과 같은 자연어처리 응용에서 중요한 역할을 하는 개체명 인식 모델을 제안하였다. 기존의 한국어 개체명 인식에 관한 연구는 규칙 기반 연구의 경우 수동으로 생성한 규칙이나 어휘사전에 매우 의존적이고, 통계기반의 연구의 경우 개체명이 태깅된 대량의 학습데이터를 필요로 하므로 새로운 도메인으로의 이식성 관점에서 한계가 있다. 이를 극복하기 위해 본 논문에서는 개체명이 태깅되지 않은 학습데이터를 이용하여 Cotraining 기반 학습을 수행함으로써 개체명 인식을 위한 규칙과 사전을 자동적으로 확장하였다. 실험 결과, 경제분야 문서에 대해 87.6%의 정확률을 보였다.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.271.1-271.1
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• 2002

Sphingolipids have been emerged as bioactive lipid modulators that mediate a variety of cell functions. However. the effects of sphingolipids on the cell growth and survival of melanocytes are not yet known. In the present study, we investigated the actions of sphingolipids in Mel-Ab melanocytes. We observed the cytoprotective effect of sphingosine-1-phosphate (SPP) on UVB-induced cell death. (omitted)