• Journal of the Korean Society for Precision Engineering
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• v.22 no.6 s.171
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• pp.76-82
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• 2005

In this paper, the pole placement controller based on the Robust Internal-loop Compensator (RIC) structure, which has inherent structural equivalence to disturbance observer, is proposed to control a linear positioning system. This controller has the advantage to easily select controller gains by using pole placement without loss of that of original RIC structure. The principal is to construct the pole placement controller for a nominal internal model instead of unknown real plant. Using linear motion experiment showed the effectiveness of the proposed controller.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.12
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• pp.1379-1387
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• 2011

A PID-feedforward controller and Robust Internal-loop Compensator (RIC) based on reinforcement learning using random variable sequences are provided to auto-tune parameters for each controller in the high-precision position control of PMLSM (Permanent Magnet Linear Synchronous Motor). Experiments prove the well-tuned controller could be reduced up to one-fifth level of tracking errors before learning by reinforcement learning. The RIC compared to the PID-feedforward controller showed approximately twice the performance in reducing tracking error and disturbance rejection.

• Journal of the Korean Mathematical Society
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• v.44 no.4
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• pp.941-947
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• 2007

Let M be a complete Riemannian manifold and let N be a Riemannian manifold of nonpositive scalar curvature. Let ${\mu}0$ be the least eigenvalue of the Laplacian acting on $L^2-functions$ on M. We show that if $Ric^M{\ge}-{\mu}0$ at all $x{\in}M$ and either $Ric^M>-{\mu}0$ at some point x0 or Vol(M) is infinite, then every harmonic morphism ${\phi}:M{\to}N$ of finite energy is constant.

• The Journal of Korea Robotics Society
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• v.14 no.4
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• pp.348-356
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• 2019

The backdrivable servovalve is a desirable component for force and interaction control of hydraulic actuation systems because it provides direct force generation mechanical impedance reduction by its own inherent backdrivability. However, high parametric uncertainty and friction effects inside the hydraulic actuation system significantly degrade its advantage. To solve this problem, this letter presents a disturbance-adaptive robust internal-loop compensator (DA-RIC) to generate ideal interactive control performance from the backdrivable-servovalve-based system. The proposed control combines a robust internal-loop compensator structure (RIC) with an explicit disturbance estimator designed for asymptotic disturbance tracking, such that the controlled system provide stable and ideal dynamic behavior for impedance control, while completely compensating the disturbance effects. With the aid of a backdrivable servovalve, we show that the proposed control structure can be implemented based on a simplified nominal model, and the controller enables implementation without accurate knowledge of the target system parameters and disturbances. The performance and properties of the proposed controller are verified by simulation and experiments.

• Applied Chemistry for Engineering
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• v.18 no.3
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• pp.213-217
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• 2007

Decomposition of benzene and selectivity of byproducts were investigated by using Dielectric Barrier Discharge (DBD) at atmospheric pressure. In order to increase the decomposition rate and selectivity of byproducts, two types of catalysts, H-ZSM-5 and Na-Y, were optionally employed inside the reactor of the process. The decomposition efficiency of benzene was investigated on the DBD and DBD/catalyst systems at various processing parameters including discharge voltage, residence time, and concentration of benzene. The results showed that, compared with the DBD only, the catalyst-assisted DBD process as a hybrid discharge type had an improved decomposition efficiency at the same process conditions of discharge voltage and residence time

• The Korea Journal of Herbology
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• v.30 no.5
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• pp.23-28
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• 2015

Objectives : The aim of this study is to investigate cell viability, anti-inflammatory, antioxidant, immunoenhancing activity using various extracts of Yeonsan Ogye.Methods : In order to evaluate cytotoxicity, MTT assay was performed. We investigated production levels of pro-inflammatory cytokines such as tumor necrosis factor (TNF)-αand interleukin (IL)-6, and nitric oxide(NO) in LPS-induced RAW 264.7 cells. NO production in RAW 264.7 cells was measured by using Griess reagent. Cytokines including IL-6 and TNF-αwere measured by Luminex and ROS was measured by Flow cytometry.Results : No cytotoxicity of various extracts of Yeonsan Ogye was observed in RAW 264.7 cells. Productions of ROS in RAW 264.7 cells were increased from extraction of bones and decreased from extraction of skin. Also, productions of NO in RAW 264.7 cells were increased to bone extract and decreased at skin extract. In addition, productions of pro-inflammatory cytokines (IL-6 and TNF-α) in LPS-induced RAW 264.7 cells were decreased at skin, meat extracts, respectively. Finally, the levels of immune-related cytokines (IL-6 and TNF-α) were increased compared to those of the normal group.Conclusions : It is concluded that Yeonsan Ogye extracts seem to have significant biological activities likes anti-inflammatory, antioxidant, immuno-enhancing etc. These results may be developed as a raw material for new health food and new therapeutics to ease the symptoms related with inflammatory and oxidative stress. In terms of oriental traditional medicine, we expect that it contribute to building of EBM (Evidence-Based Medicine) from the this result.

• Nutrition Research and Practice
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• v.11 no.3
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• pp.180-189
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• 2017

BACKGROUND/OBJECTIVES: Recent living condition improvements, changes in dietary habits, and reductions in physical activity are contributing to an increase in metabolic syndrome symptoms including diabetes and obesity. Through such societal developments, humankind is continuously exposed to metabolic diseases such as diabetes, and the number of the victims is increasing. This study investigated Cordyceps militaris water extract (CMW)-induced glucose uptake in HepG2 cells and the effect of CMW treatment on glucose metabolism. MATERIALS/METHODS: Colorimetric assay kits were used to determine the glucokinase (GK) and pyruvate dehydrogenase (PDH) activities, glucose uptake, and glycogen content. Either RT-PCR or western blot analysis was performed for quantitation of glucose transporter 2 (GLUT2), hepatocyte nuclear factor 1 alpha ($HNF-1{\alpha}$), phosphatidylinositol 3-kinase (PI3k), protein kinase B (Akt), phosphorylated AMP-activated protein kinase (pAMPK), phosphoenolpyruvate carboxykinase, GK, PDH, and glycogen synthase kinase 3 beta ($GSK-3{\beta}$) expression levels. The ${\alpha}-glucosidase$ inhibitory activities of acarbose and CMW were evaluated by absorbance measurement. RESULTS: CMW induced glucose uptake in HepG2 cells by increasing GLUT2 through $HNF-1{\alpha}$ expression stimulation. Glucose in the cells increased the CMW-induced phosphorylation of AMPK. In turn, glycolysis was stimulated, and glyconeogenesis was inhibited. Furthermore, by studying the mechanism of action of PI3k, Akt, and $GSK-3{\beta}$, and measuring glycogen content, the study confirmed that the glucose was stored in the liver as glycogen. Finally, CMW resulted in a higher level of ${\alpha}-glucosidase$ inhibitory activity than that from acarbose. CONCLUSION: CMW induced the uptake of glucose into HepG2 cells, as well, it induced metabolism of the absorbed glucose. It is concluded that CMW is a candidate or potential use in diabetes prevention and treatment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.1
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• pp.18-22
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• 2014

The antibacterial activities of methanol extracts of 19 commercial herbal medicines were measured against the fish pathogens Vibrio ichthyoenteri and Streptococcus iniae, which cause several fish diseases. Rhus javanica showed the strongest antibacterial activity against V. ichthyoenteri and S. iniae. The methanol extract of R. javanica was extracted further using several organic solvents with different polarities. The extract from the ethyl acetate fraction showed strong activity against both fish pathogens. The minimum inhibitory concentration (MIC) of the R. javanica extract was $32{\mu}g/mL$ for V. ichthyoenteri and $128{\mu}g/mL$ for S. iniae. Further purification and isolation of the active compound (s) responsible for these activities and further study of the synergistic effect using combinations of antibiotics against pathogenic bacteria are needed.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.875-879
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• 2009

In this paper, we propose the measurement camera system of flight data of golfball for the application of screen golf contents. The existing flight data extraction system that applied on the screen golf content divided plate is dependent on it. in this paper, the camera system install in the ceiling that is able to look at passing golf ball. And left-handed and left-handed bats in the clear of the restrictions. Using high-speed CCD camera is shooting the ball flying. Acquired image is calculated from the coordinates. The location information of the calculated golf ball calculates a speed and a direction by using the physical formula, it applies the golf contents. After this system is useful sports type contents baseball, soccer, tennis.

• The Journal of Korean Institute for Practical Engineering Education
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• v.2 no.1
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• pp.115-119
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• 2010

In Korea, there exist around 120 regional innovation centers(RICs) which have been established in many universities since the mid-nineties by Ministry of Knowledge Economy of Korea. These centers aim at higher competitiveness of their local industry by providing it with direct services using expensive testing or manufacturing equipment along with cooperative technology development and well trained work forces. Considering the nationwide importance of human resources development in the key industrial sectors, the RICs naturally should take part of responsibility because the most advanced equipments in each important industrial field have been invested during the last 15 years which amount over 500 million US dollars. In the present study, a brief concept for the industry-oriented human resources development program utilizing the already established RIC infrastructure is proposed.