• Journal of the Institute of Electronics Engineers of Korea SP
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• v.37 no.5
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• pp.21-30
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• 2000

As a means of getting over the linguistic barrier between different languages, a sign-language communication system using CG animation techniques has been studied. In order to generate a kind of sign-language animation in the system, the joint angles of the arms and the hands corresponding to the gesture have to be determined Up to date, however, the values of joint angles have been decided by trial-and-error methods based on the animator's experiences To overcome the drawback, m this paper, we design an integrated keyframe editor of the arms and the hands for 3D sign-language animation with which we can easily and quickly generate the keyframes of the sign-language animation required to build up In the Implemented keyframe editor, the values of joint angles are calculated by using mverse kinematics, and the same transformation matrix is applied to the joints of two arms and twenty fingers Experimental results show a possibility that the editor could be used efficiently for making up the sign-language communication dictionaries needed for inter-communication between different languages.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.231.1-231.1
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• 2015

Surface energy, being an important material parameter to control its interactions with the other surfaces plays a key role in bio-related application. Carbon films are found very promising due to their characteristics such as wear and corrosion resistant, high hardness, inert, low resistivity and biocompatibility. The present work deals with the deposition of carbon films using unbalanced facing target magnetron sputtering technique. The discharge characteristics were studied using optical emission spectroscopy and correlated with the film properties. Surface energy was investigated through contact angle measurement. The ID/IG ratio as calculated from Raman spectroscopy data increases with the increase in power density due to the higher number of sp2 clusters embedded in the amorphous matrix. The deposited films were smooth and homogeneous as observed by Atomic force microscopy having RMS roughness in the range of 1.74 to 2.25 nm. It is observed that electrical resistivity and surface energy varies in direct proportionality with operating pressure and has inverse relation with power density. The surface energy results clearly exhibited that these films can have promising applications in cell cultivation.

• Korean Journal of Materials Research
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• v.26 no.12
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• pp.751-756
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• 2016

Graphite was diffusion-bonded by hot-pressing to W-25Re alloy using a Ti interlayer. For the joining, a uniaxial pressure of 25 MPa was applied at $1600^{\circ}C$ for 2 hrs in an argon atmosphere with a heating rate of $10^{\circ}C\;min^{-1}$. The interfacial microstructure and elemental distribution of the W-25Re/Ti/Graphite joints were analyzed by scanning electron microscopy (SEM). Hot-pressed joints appeared to form a stable interlayer without any micro-cracking, pores, or defects. To investigate the high-temperature stability of the W-25Re/Ti/Graphite joint, an oxy-acetylene torch test was conducted for 30 seconds with oxygen and acetylene at a 1.3:1 ratio. Cross-sectional analysis of the joint was performed to compare the thickness of the oxide layer and its chemical composition. The thickness of W-25Re changed from 250 to $20{\mu}m$. In the elemental analysis, a high fraction of rhenium was detected at the surface oxidation layer of W-25Re, while the W-25Re matrix was found to maintain the initial weight ratio. Tungsten was first reacted with oxygen at a torch temperature over $2500^{\circ}C$ to form a tungsten oxide layer on the surface of W-25Re. Then, the remaining rhenium was subsequently reacted with oxygen to form rhenium oxide. The interfacial microstructure of the Ti-containing interlayer was stable after the torch test at a temperature over $2500^{\circ}C$.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.4
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• pp.437-442
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• 2012

To analyze a multibody system, this paper proposes an implicit numerical integration method for joint coordinates subsystem synthesis method. To verify the proposed method, a multibody model for an unmanned robot vehicle, which consists of six identical independent suspension systems, is developed. The symbolic method is applied to compute the system Jacobian matrix for the implicit integration method. The proposed method is also verified by performing rough terrain run-over simulation in comparison with the conventional implicit integration method. In addition, to evaluate the efficiency of the proposed method, the CPU time obtained by using this method is compared with that obtained by using the conventional implicit method.

• Journal of the Korean Society of Physical Medicine
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• v.2 no.2
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• pp.151-159
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• 2007

Purpose : The purpose of the study was to investigate the effect of cold application on knee joint in rats induced by osteoarthritis. Methods : Osteoarthritis was induced in female Sprague-Dowley rats by injecting into articular cavity of knee joint with 4% Kaolin, 2% carrageenan. Rats were divided randomly into the control and MES applicated group. The Experimental group was applicated MES in rat knee joint for 30 minutes. Results : Recovery of articular cartilage surface and thickness of articular cartilage increased after MES application. And chondrocytes were distributed widely throughout the cartilage matrix. The physical effects of Microcurrent Electrical Stimulation. Decrease in blood flow. Delay of neurotransmitter velocity Decrease in metabolism activity and inhibit the progress of the infection. Decrease in pain and muscle rigidity, inhibition of circulation Conclusion : This study shows that MES application affects articular cartilage recovery in osteoarthritis.

• Journal of Acupuncture Research
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• v.22 no.2
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• pp.171-180
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• 2005

Background & Objective : Angiogenesis consists of the proliferation, migration, and differentiation of endothelial cells, and angiogenic factors and matrix protein interactions modulate this process. The aim of this study was to determine whether Puerariae radix could induce angiogenic activity in human umbilical vein endothelial cells (HUVECs). Methods: The angiogenic activity of Puerariae radix were evaluated by using BrdU assay, chemotactic migration assay, tube formation assay, measurement of bFGF in HUVECs, and Matrigel plug assay in mice. Results : Puerariae radix significantly increased HUVECs proliferation in a dose-dependent manner. In addition, Puerariae radix increased migration and tube-like formation in HUVECs. Interestingly,the expression of basic fibroblast growth factor (bFGF), an angiogenesis-stimulating growth factor, was dose-dependently increased by Puerariae radix. The angiogenic activity of Puerariae radix was confirmed using an in vivo Matrigel angiogenesis model, showing promotion of blood vessel formation. Conclusion : Puerariae radix significantly induces angiogenesis in vitro and in vivo. These results suggest that Puerariae radix is a potent angiogenic agent, and a promising drug, for the induction of neovascularization.

• Korean Journal of Pharmacognosy
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• v.49 no.4
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• pp.305-311
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• 2018

Osteoarthritis (OA) is the most common form of joint disease, characterized by articular cartilage, osteonecrosis, and osteochondral bone erosion. It is an early, progressive disease that combines joint stiffness and joint pain and reduces cartilage function and condition. Interleukin-1 beta ($IL-1{\beta}$) is thought to be important to the pathogenesis of OA and significantly increases the expression of matrix metalloproteinases (MMPs), which play an important role in cartilage degradation in OA. Sparassis crispa (Wulf.) is an edible / medicinal mushroom that has been reported to variety of biological activities. In this study, investigated the Anti-inflammatory effect of Sparassis crispa (Wulf.) ethanol extract (SCE) on $IL-1{\beta}$ stimulated SW1353 chondrocytes. SCE decreased the expression and activity of MMPs by $IL-1{\beta}$ and decreased the levels of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) associated with the inhibition of prostaglandin E2($PGE_2$) in $IL-1{\beta}$ stimulated SW-1353 chondrocytes. In addition, SCE inhibits the expression of MAPK (mitogen-activated protein kinase) and $NF-{\kappa}B$ (nuclear factor-kappa B) signaling in $IL-1{\beta}$ stimulated SW-1353 cells, and SCE inhibits the production of reactive oxygen species (ROS) through heme oxygenase-1 (HO-1) expression. Thus, it is suggested that SCE has a potential as an anti-inflammatory agent in osteoarthritis treatments.

• IMMUNE NETWORK
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• v.22 no.2
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• pp.14.1-14.17
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• 2022

Osteoarthritis (OA) is a common degenerative joint disease characterized by breakdown of joint cartilage. Mitochondrial dysfunction of the chondrocyte is a risk factor for OA progression. We examined the therapeutic potential of mitochondrial transplantation for OA. Mitochondria were injected into the knee joint of monosodium iodoacetate-induced OA rats. Chondrocytes from OA rats or patients with OA were cultured to examine mitochondrial function in cellular pathophysiology. Pain, cartilage destruction, and bone loss were improved in mitochondrial transplanted-OA rats. The transcript levels of IL-1β, TNF-α, matrix metallopeptidase 13, and MCP-1 in cartilage were markedly decreased by mitochondrial transplantation. Mitochondrial function, as indicated by membrane potential and oxygen consumption rate, in chondrocytes from OA rats was improved by mitochondrial transplantation. Likewise, the mitochondrial function of chondrocytes from OA patients was improved by coculture with mitochondria. Furthermore, inflammatory cell death was significantly decreased by coculture with mitochondria. Mitochondrial transplantation ameliorated OA progression, which is caused by mitochondrial dysfunction. These results suggest the therapeutic potential of mitochondrial transplantation for OA.

• The Korean Journal of Pain
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• v.13 no.1
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• pp.1-7
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• 2000

Background: Intraarticular local anesthetic injection has been therapeutically applied for pain control in various arthritis patients. However, little physiologic effects of local anesthetics on their tissue were known. This study was conducted to determine its effects on the cell proliferation and matrix metalloproteinases (MMP) production of cultured fibroblast like synoviocytes (FLS) derived from synovial tissues of rheumatoid arthritis patients. Methods: Bupivacaine with varying concentrations 0 (control), 0.1, 0.25, 0.5% was applied to experimental cell groups growing as monolayers in culture plates for varying durations 0 (control), 30, 90, 180 seconds in the presence and absence of interleukin-$1\beta$. Results: No statistical significances were noted in thymidine incorporation between 0, 30, 90 and 180 seconds exposure groups with 0.5% bupivacaine after 1 day and 2 days. Thymidine incorporation between 0, 0.1, 0.25, 0.5% exposure groups 1 day and 2 days after 90 seconds exposure did not show any differences. After exposure to bupivacaine, there were statistically significant increases in MMP-1 (p=0.025) and MMP-3 productions (p=0.000) of FLS in the absence of IL-$1\beta$, but no differences among the groups in the presence of IL-$1\beta$. Conclusion: We concluded that in this short-term in vitro study, bupivacaine does not have injurious effect on cultured rheumatoid arthritic joint tissues. The long-term effect cannot be known from this investigation.

• The Journal of the Korean bone and joint tumor society
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• v.18 no.2
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• pp.83-88
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• 2012

We reviewed the clinical features of 2 patients who underwent surgery for subungal exostosis, focusing on postoperative deformity of the nail. The lesion destroyed the nail bed and was excised with a direct approach. then thin split-thickness sterile matrix graft was done after excision of the tumor because the defect of the nail bed was large. Good postoperative appearance of the nail was obtained by thin split-thickness sterile matrix graft. The use of thin split-thickness sterile matrix graft for the replacement of a nail bed defect can regain a smooth, adherent, and normal-looking nail and avoid donor-site morbidity. Thin split-thickness toe-nail bed graft is a good choice for the prevention of postoperative deformity.