• 조명전기설비학회논문지
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• 제24권9호
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• pp.44-48
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• 2010

This paper presents an LMI-based method to design an integral sliding mode controller for an uncertain system with a polytopic model. The uncertain system under consideration may have mismatched parameter uncertainties in the state matrix as well as in the input matrix. Using LMIs we derive an existence condition of a sliding surface. And we give a switching feedback control law.

• 전력전자학회논문지
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• 제15권1호
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• pp.9-16
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• 2010

본 논문은 CAN을 사용하여 매트릭스 컨버터로 구동되는 천정형 크레인의 총괄제어 기법을 제시하였다. 크레인의 갠추리, 트롤리 및 호이스트 구동용으로 4개 매트릭스 컨버터-유도전동기 구동장치를 직접토크 기법으로 위치 제어한다. 위치제어 알고리즘과 CAN을 사용한 크레인의 총괄제어 기법을 제시하고, 시뮬레이션 및 실험을 통하여 매트릭스 컨버터-유도전동기로 구동되는 크레인의 위치제어 성능을 확인한다.

• 제어로봇시스템학회논문지
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• 제18권9호
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• pp.806-811
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• 2012

In this paper Hartley functions are used to approximate the solutions of continuous time linear dynamical system. The Hartley function and its integral operational matrix are first presented, an efficient algorithm to solve the Stein equation is proposed. The algorithm is based on the compound matrix and the inverse of sum of matrices. Using the structure of the Hartley's integral operational matrix, the full order Stein equation should be solved in terms of the solutions of pure algebraic matrix equations, which reduces the computation time remarkably. Finally a numerical example is illustrated to demonstrate the validity of the proposed algorithm.

• Journal of Nutrition and Health
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• 제38권2호
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• pp.104-111
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• 2005

Tumor invasion is composed of four steps: cell adhesion to the extracellular matrix, degradation of the extracellular matrix components, tumor cell motility followed by cell detachment. Matrix metalloproteinases (MMPs) are important proteinases that associated with degradation of matrix component. Epigallocatechin gallate (EGCG) is a major polyphenotic constituent of green tea. In the study, we examined the anti-invasive and MMP activity suppression effects of EGCG in MDA-MB-231 human breast cancer cells. MDA-MB-23l human breast cancer cells were cultured with various concentrations 0 - 100 μM of EGCG. EGCG significantly inhibited the cell adhesion to the fibronectin. Cell motility through gelatin filter and invasion to Matrigel were inhibited dose-dependently by EGCG treatment. EGCG also inhibited the activities of MMP-2, -9 and the amount of MMP-9 (α = 0.05). Therefore, EGCG may contribute to the potential beneficial food component to prevent the invasion and metastasis in breast cancer. (Korean J Nutrition 38(2): 104～111, 2005)

• 한국수학교육학회지시리즈A:수학교육
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• 제34권1호
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• pp.7-9
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• 1995

• Journal of Pharmaceutical Investigation
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• 제29권1호
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• pp.7-12
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• 1999

The captopril matrix tablets composed of polyethylene oxide(PEO) was prepared and administered to beagle dogs. Captopril matrix tablets were prepared using direct compressed method and wet granulation compressed method with various ratios of drug to PEO. The diffusion rate of captopril matrix tablets followed on the Higuchi's diffusion model. With increasing hardness of captopril matrix tablets, release rate was decreased. Each formulation was evaluated by the area under the curve (AUC) and time course of plasma captopril concentration after oral administration to beagle dogs. The $AUC_{0-12}$ were $9.126\;{\mu}g\;h/ml$ and $6.417\;{\mu}g\;h/ml$ for the matrix tablets and conventional tablets, respectively. Therefore, the bioavailability of captopril matrix tablets was greater than that of commercial product. It is suggested that captopril matrix tablets using PEO is a useful sustained release formulation.

• IMMUNE NETWORK
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• 제4권2호
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• pp.116-122
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• 2004

Background: LIGHT (TNFSF14) is a member of tumor necrosis factor superfamily and is the ligand for TR2 (TNFRSF14/HVEM). LIGHT is known to have proinflammatory roles in atherosclerosis. Methods: To find out the expression pattern of LIGHT in atherosclerotic plaques, immunohistochemical analysis was performed on human carotid atherosclerotic plaque specimens. LIGHT induced atherogenic events using human monocytic cell line THP-1 were also investigated. Results: Immunohistochemical analysis revealed expression of LIGHT and TR2 in foam cell rich regions in the atherosclerotic plaques. Double immunohistochemical analysis further confirmed the expression of LIGHT in foam cells. Stimulation of THP-1 cells, which express TR2, with either recombinant LIGHT or immobilized anti-TR2 monoclonal antibody induced interleukin-8 and matrix metalloproteinase(MMP)-9. Electrophoretic mobility shift assay demonstrated that LIGHT induces nuclear localization of transcription factor, nuclear factor $(NF)-{\kappa}B$. LIGHT induced activation of MMP-9 is mediated by $NF-{\kappa}B$, since treatment of THP-1 cells with the $NF-{\kappa}B$ inhibitor PDTC (pyrrolidine dithiocarbamate) completely blocked the activation of MMP-9. Conclusion: These data indicate that LIGHT is expressed in foam cells in atherosclerotic plaques and is involved in atherogenesis through activation of pro-atherogenic cytokine IL-8 and destabilization of plaque by inducing matrix degrading enzyme.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제9권1호
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• pp.63-72
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• 2002

An inverse interpolation problem for rational matrix functions with a certain type of symmetricity in zero-pole structure is studied.

• Asian Pacific Journal of Cancer Prevention
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• 제16권15호
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• pp.6749-6751
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• 2015

Background: Laryngeal cancer is an important malignancy in head and neck area and squamous cell carcinoma (SCC) is the most common type accounting for 95% of cases. Increase in matrix metalloproteinases (MMPs) in different tumors and their correlation with tumor invasiveness has been documented. However, most studies have evaluated MMP-2 and MMP-9 expression and few have evaluated serum levels. The aim of current study was to evaluate serum levels in patients with laryngeal SCC compared to normal subjects and assess any relation with tumor clinicopathological findings. Materials and Methods: In this case control study, 20 patients with oral SCC and 20 healthy subjects were included. Serum levels of MMP-2 and MMP-9 were compared between groups and correlations with findings including grade (T) and node involvement (N) were evaluated. Results: Patients with laryngeal SCC had significantly higher serum levels of MMP-2 (p=0.01) and MMP-9 (p=0.03) compared to healthy subjects. Patients with higher T stage (T3,4) had significantly higher MMP-2 (p=0.04) and MMP-9 (p=0.01). There was significant positive correlation between serum levels of MMP-2 with T stage (r=0.45, p=0.04) and lymph node involvement (r=0.563, p=0.01) and between levels of MMP-9 with T stage (r=0.527, p=0.01). Conclusions: Our results showed that compared to healthy subjects, both MMP-2 and MMP-9 are significantly increased in serum of laryngeal SCC cases. MMP-2 was correlated with lymph node involvement while MMP-9 has stronger correlation with T stage compared to MMP-2.

• The Korean Journal of Pain
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• 제36권1호
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• pp.72-83
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• 2023

Background: Globally, spinal cord injury (SCI) results in a big burden, including 90% suffering permanent disability, and 60%-69% experiencing neuropathic pain. The main causes are oxidative stress, inflammation, and degeneration. The efficacy of the stem cell secretome is promising, but the role of human neural stem cell (HNSC)-secretome in neuropathic pain is unclear. This study evaluated how the mechanism of HNSC-secretome improves neuropathic pain and locomotor function in SCI rat models through antioxidant, anti-inflammatory, anti-matrix degradation, and neurotrophic activities. Methods: A proper experimental study investigated 15 Rattus norvegicus divided into normal, control, and treatment groups (30 µL HNSC-secretome, intrathecal in the level of T10, three days post-traumatic SCI). Twenty-eight days post-injury, specimens were collected, and matrix metalloproteinase (MMP)-9, F2-Isoprostanes, tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-β, and brain derived neurotrophic factor (BDNF) were analyzed. Locomotor recovery was evaluated via Basso, Beattie, and Bresnahan scores. Neuropathic pain was evaluated using the Rat Grimace Scale. Results: The HNSC-secretome could improve locomotor recovery and neuropathic pain, decrease F2-Isoprostane (antioxidant), decrease MMP-9 and TNF-α (anti-inflammatory), as well as modulate TGF-β and BDNF (neurotrophic factor). Moreover, HNSC-secretomes maintain the extracellular matrix of SCI by reducing the matrix degradation effect of MMP-9 and increasing the collagen formation effect of TGF-β as a resistor of glial scar formation. Conclusions: The present study demonstrated the mechanism of HNSC-secretome in improving neuropathic pain and locomotor function in SCI through antioxidant, anti-inflammatory, anti-matrix degradation, and neurotrophic activities.