• Journal of the Korean Society for Precision Engineering
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• v.19 no.6
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• pp.119-127
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• 2002

The paper presents the effect of the backlash magnitude and the supplied voltage of motor on the gear reduction servo system. The bandwidth of the system depends heavily on the supplied voltage of motor as well as the backlash magnitude. Specially, the bandwidth of the system increases as the supplied voltage of motor increases. 1t is shown that the system has the bandwidth of zero backlash in case of motor supplied voltage is infinite. It is also found that the magnitude of the supplied voltage of motor is very important in case of the analysis of the system bandwidth.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.13-34
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• 2003

Fructose-1, 6-diphosphate (FOP), a glycolytic metabolite is reported to ameliorate inflammation and inhibit the nitric oxide production in murine macrophages stimulated with endotoxin. It is also reported that FOP has cytoprotective effects against hypoxia or ischemia/reperfusion injury in brain and heart. In this study, we examined whether FDP has protective effects on UV-induced oxidative damage in skin cell culture system and human skin in vivo. FDP had a protective role in UVB-induced LDH release and ROS accumulation in HaCaT although it did not show direct radical scavenging effect in the experiment using 1, 1-diphenyl-2-picrylhydrazyl (DPPH). FDP also preserved cellular GSH content after UV irradiation in HaCaT and normal human fibroblast culture system. Cellular oxidative stress induces multiple downstream signaling pathways that regulate expression of multiple gene including MMP-1 and collagen, we examined the effects of FDP on UV-induced alteration of these protein expression in fibroblast culture and human skin in vivo. The increased MMP-1 expression in fibroblast and human skin by UV irradiation was significantly decreased by FDP. FDP also prevented the UV-induced decrease of collagen expression in fibroblast and human skin. Moreover, the decreasing the intracellular levels of reducing equivalents in human fibroblast by glutathione (GSH) depletion lowered the UVA dose threshold for reduction of procollagen expression, indicating that the differences of glutathione contents define the susceptibility of fibroblasts towards UV-induced reduction of procollagen expression. FDP also preserved cellular GSH content after UV irradiation, indicating that FDP has protective effects on UV-induced reduction of procollagen expression, which are possibly through maintaining intracellular reducing equivalent. Based on these premises, we examined the effect of daily use of a moisturizer containing FDP on facial wrinkle in comparison with vehicle moisturizer lacking FDP. In the clinical study, FDP significantly decreased facial wrinkle compared with vehicle alone after 6 months of use. Our results suggest that FDP has anti-aging effects in skin by increasing cellular antioxidant system and preventing oxidative signal and inflammatory reaction. Therefore FDP may be useful anti-aging agent for cosmetic purpose.

• The Korea Journal of Herbology
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• v.20 no.4
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• pp.1-10
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• 2005

Objectives : We investigated the anti-aging effect on skin with the extract of the needles of red pine, Pinus densiflora. Methods : We measured various effects related to skin such as the anti-oxidant effect, the protection against ultraviolet (UV) irradiation, the inhibition of reactive oxygen species (ROS) generation, the induction of heat shock protein 70 (HSP70), the reduction of matrix metalloproteinase-2 (MMP-2) synthesis and senescent cell. Results : The results were as follows : The extract of the needles of red pine (RP) had the potent anti-oxidant effect and the ROS scavenging effect. Also RP preserved the systemic anti-oxidant enzyme system (superoxide dismutase and catalase) from UVB irradiation. RP protected the cell membrane from the damages induced by UVB irradiation. RP induced HSP70, a mediator of resistance to UVB irradiation. RP reduced the synthesis of MMP-2 induced by UVB irradiation. And RP inhibited the amount of senescent-associated (SA) ${\beta}-galactosidase$ staining, as a marker of replicative senescence. Conclusions : The results of our study indicate that the extract of the needles of red pine, Pinus densiflora, has anti-aging effects on skin.

• Molecules and Cells
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• v.43 no.3
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• pp.251-263
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• 2020

Flagellin, a major structural protein of the flagellum found in all motile bacteria, activates the TLR5- or NLRC4 inflammasome-dependent signaling pathway to induce innate immune responses. Flagellin can also serve as a specific antigen for the adaptive immune system and stimulate anti-flagellin antibody responses. Failure to recognize commensal-derived flagellin in TLR5-deficient mice leads to the reduction in anti-flagellin IgA antibodies at steady state and causes microbial dysbiosis and mucosal barrier breach by flagellated bacteria to promote chronic intestinal inflammation. Despite the important role of anti-flagellin antibodies in maintaining the intestinal homeostasis, regulatory mechanisms underlying the flagellin-specific antibody responses are not well understood. In this study, we show that flagellin induces interferon-β (IFN-β) production and subsequently activates type I IFN receptor signaling in a TLR5- and MyD88-dependent manner in vitro and in vivo. Internalization of TLR5 from the plasma membrane to the acidic environment of endolysosomes was required for the production of IFN-β, but not for other pro-inflammatory cytokines. In addition, we found that anti-flagellin IgG2c and IgA responses were severely impaired in interferon-alpha receptor 1 (IFNAR1)-deficient mice, suggesting that IFN-β produced by the flagellin stimulation regulates anti-flagellin antibody class switching. Our findings shed a new light on the regulation of flagellin-mediated immune activation and may help find new strategies to promote the intestinal health and develop mucosal vaccines.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.2
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• pp.159-164
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• 2015

To identify new anti-inflammatory and whitening material, this study investigated the whitening and anti-inflammatory effects of the lyophilized powder from 6 oriental plant extracts (OPE; Citrus junos Tanaka, Mori cortex Radicis, Schisandra chinensis Baillon, Coix lachrymajobi var. mayuen, Angelica gigas NAKAI, and Sophora japonica L.) fermented with Streptococcus thermophilus by assessment of cytotoxicity on human dermal fibroblast, inhibitory effect of nitric oxide (NO) prodction, tyrosinase activity and melanin formation. The OPE was fermented with Streptococcus thermophilus at $37^{\circ}C$ for 2 days and the lyophilized powder was manufactured by freezing-dryer. OPE didn't show cytotoxicity at concentration of $500{\mu}g/mL$ using a cytopathic effect reduction method. OPE also exhibited inhibitory effect on nitric oxide (NO) prodction by Griess reagent system. Furthermore, OPE showed inhibitory effect on tyrosinase activity with dose dependent manner, and exhibited significant inhibition of melanin formation by measurement of melanin from culture media (p < 0.05). From these results, 6 OPE extracts showed anti-inflammatory and whitening effect and may be used as an active ingredient for cosmetics.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.44 no.5
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• pp.20-27
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• 2007

In this paper, Air-interface protocols of ISO 18000-6 Type A and B applied to RFID system in UHF band are analyzed, and those algorithms are realized. Also, the improved anticollision algorithms for the Type A and B of ISO 18000-6 protocol are proposed and the performances are compared. As the results, reduction ratio of total tag recognition time of the improved ISO 18000-6 Type A algorithm is 35.2 % for 100 tags and 24.3% for 1000 tags with respect to standard algorithm, respectively. And the reduction ratio of the improved ISO 18000-6 Type B algorithm is 6.0% for 100 tags and 6.6% for 1000 tags. Therefore, the improved anticollision algorithm proposed in this paper is the advanced method improving the performance of tag recognition in the RFID system.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1155-1158
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• 2007

To reduce acoustic noise level of an AV projector, primary noise sources of AV projector were analyzed. Based on the analyzed result, methods to control each source are presented and tried. Structure-borne noise can be controlled by anti vibration design of mounting system, and air-borne noise by reducing flow resisitvity.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.3
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• pp.447-457
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• 1994

This paper presents a compensation method for discrete-time control systems with saturation nonlinearities to cope with the reset windup phenomena. The proposed ARW (Anti-Reset Windup) method is motivated by the concept of the equilibrium point. The design parameter of the ARW scheme is explicitly derived by minimizing a reasonable performance index. The resulting dynamics of the compensated controller exhibits the reduced model form of the unsaturated system which can be obtained by the singular perturbational model reduction method. An example is given to illustrate the effectiveness of the proposed method.

• Animal cells and systems
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• v.10 no.2
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• pp.73-77
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• 2006

Caspase-11 has been known as a dual regulator of apoptosis and inflammatory response. An unusual feature of caspase-11 is that its expression is induced by apoptotic or proinflammatory stimuli. Utilizing these unusual features of caspase-11, we have developed a simple and sensitive assay method to screen pro- or anti-apoptotic/inflammatory molecules. To develop this assay method, we generated a reporter construct where GFP expression is regulated by caspase-11 promoter. When several types of cultured cells were transfected with this reporter construct and subsequently treated with various apoptotic or proinflammatory molecules, expression of GFP by the activation of caspase-11 promoter was easily detected by fluorescence microscopy or spectrofluorometry. In addition, a reduction of the GFP fluorescence was detected when an agent reported to suppress caspase-11 induction was applied. These results suggest that our reporter system can be used to screen pro- or anti-apoptotic/inflammatory molecules.

• Journal of Ocean Engineering and Technology
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• v.19 no.5 s.66
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• pp.58-64
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• 2005

In this paper, a feedback linearizing anti-sway control law, using a 2-D model for container cranes, is investigated. The equations of motion are first derived from Lagrange's equation. Then, by substituting the sway dynamics into the trolley dynamics, a reduction of variables from three (trolley, hoist, sway) to two (trolley, hoist) is pursued. The anti-sway control law is designed based on the Lyapunov stability theorem. The proposed control law guarantees the uniform asymptotic stability of the closed-loop system. The simulation results of the derived control law, using MATLAB/Simulink, are compared with those of the sliding mode control law, noted in previous literature. Also, experimental results using a 3-D pilot crane are provided.