• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.5
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• pp.939-951
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• 2002

We propose a new multiscale Galerkin method based on interpolation wavelets for two-dimensional Poisson's and plane elasticity problems. The major contributions of the present work are: 1) full multiresolution numerical analysis is carried out, 2) general boundaries are handled by a fictitious domain method without using a penalty term or the Lagrange multiplier, 3) no special integration rule is necessary unlike in the (bi-)orthogonal wavelet-based methods, and 4) an efficient adaptive scheme is easy to incorporate. Several benchmark-type problems are considered to show the effectiveness and the potentials of the present approach. is 1-2m/s and impact deformation of the electrode depends on the strain rate at that velocity, the dynamic behavior of the sinter-forged Cu-Cr is a key to investigate the impact characteristics of the electrodes. The dynamic response of the material at the high strain rate is obtained from the split Hopkinson pressure bar test using disc-type specimens. Experimental results from both quasi-static and dynamic compressive tests are Interpolated to construct the Johnson-Cook model as the constitutive relation that should be applied to simulation of the dynamic behavior of the electrodes. The impact characteristics of a vacuum interrupter are investigated with computer simulations by changing the value of five parameters such as the initial velocity of a movable electrode, the added mass of a movable electrode, the wipe spring constant, initial offset of a wipe spring and the virtual fixed spring constant.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4371-4377
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• 2012

In this paper, the structure-fluid coupled analysis is carried out in order to examine the cause of the vibration induced by fluid in the pressure-reducing valves for water. It is confirmed that there is the noise at the area of low frequency of 250Hz by measuring noise at pressure reducing valve. The flow analysis is performed by the commercial software ANSYS/CFX. The flow velocity of about 40 m/s is formed by nozzle effect, and so negative pressure is happened in the pressure reducing valve. The structure analysis is carried out with the load condition of pressure distribution by flow formed in valve. The rubber material at disk is deformed to the extent of closing up flow passage. It is confirmed that the disc deformation which is occurred repeatedly is due to noise and vibration at the pressure reducing valve.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.2
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• pp.162-167
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• 2010

This is a case report about patient who had suffered from degenerative joint disease and treated by TMJ reconstruction with condylar prosthesis. The patient visited Korea University An-am hospital on 2007 complaining symptom about both TMJ pain, mouth opening limitation and open bite. From CT view there was severe resorption of both condylar head, therefore condylar prosthesis reconstruction was planned. After 3D RP model analysis for preparation, the patient was operated under general anesthesia for condylar prosthesis reconstruction and the symptom was alleviated. (increased mouth opening, reduced anterior open bite, full mouth occlusal contact achieved) Follow up was carried out monthly, but after this, patient refused follow up. After 26 months from the operation, the patient revisited for anterior open bite. In clinical evaluation, occlusal contact was remained, but anterior open bite was relapsed. From cephalometry analysis, severe resorption of glenoid fossa was found. Therefore, Autogenous disc reconstruction with alloplastic material was planned on August 2009. After another surgery, condylar prosthesis was regained its normal position in glenoid fossa, and occlusion was recovered properly.

• The Korea Journal of Herbology
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• v.30 no.5
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• pp.51-58
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• 2015

Objectives : This paper aimed to verify the applicability of mixed extract ofAngelica gigasNakai,Cnidium officinaleMakino,Paeoniala ctifloraPall,Rechmannia glutinosaLibosch,Scutellaria baicalensisGeorgi, which were prescribed for improving inflammation in Donguibogam, as the materials for beauty food and functional medicinal herb cosmetics by manufacturing such mixed extract and evaluating the biological activity of the extract.Methods : The mixed medicinal herb water extract(MMW) and ethanol extract(MME) were freeze-dried to be used as the specimen. We performed electron donating ability, lipid acidification inhibitory activity, anti-inflammatory activity against skin flora, MTT assay, NO inhibitory activity and the protein expression inhibitory activity of iNOS and COX-2.Results : For anti-oxidation experimentation, the electron donating abilities of MMW and MME were above 60.0% and 90.0% at 500 μg/ml, respectively. In the inhibition rate of lipid peroxidation, MMW and MME showed 43.1% and 52.1% at 1,000 μg/ml, respectively. As a result of antimicrobial activity, both the MMW and MME showed significant clear zones forPropionibacterium acnesat 4 mg/disc, but did not indicated the clearzones forStaphylococcus aureus, Escherichia coliandStaphylococcus epidermidis. Anti-inflammatory activity by NO assay showed LPS-induced NO was significantly inhibited in a concentration-dependent manner. Also, the expression of iNOS and COX-2 proteins were significantly inhibited following treatment with MMW and MME of 50 μg/ml.Conclusions : Accordingly, it can be concluded that mixed medicinal herb extract has the potential to beused as a functional food and cosmetic material.

• Economic and Environmental Geology
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• v.33 no.2
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• pp.147-163
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• 2000

The Buseok pluton in the Yeongju Batholith is a comagmatic plutonic rocks which haveconcentrically compositional zoning. The lithofacies of the Buseok pluton comprise hornblende biotite tonalite in the southern part of the pluton, porphyritic and equigranular biotite granodiorite in the northern part and biotite granite in the north-central part. The compositional variations change gradually with continuity both within and between the lithofacies. The concentrically zoned pattern is relatively mafic rocks composed of high-temperature mineral assemblages in margin of the southern part, passing inward and northward gradually to more felsic rock in core of the north-central part. Changes in the textures and microstructures, as well as in the mineral content, take place between rock types of the plutons. Darker colored, generally coarse-grained, well foliated tonalite pass inward to light colored, coarse-grained, poorly foliated granodiorite, and finally give way to lighter colored, medium-grained, nearly nonfoliated granite. The foliation are best developed in the marginal part of the tonalite. Here, the regional myolitic foliation in the tonalite is steep northward and parallels to its southeastern contact with the country rock, but the magmatic foliation from disc-shaped mafic microgranitoid enclaves is subvertical and parallels the contacts with the country rock. As the tonalite approaches biotite granite in composition, the foliation is indistinct. Modal and chemical data for the pluton show quantitative compositional variation from the margin of the southern part to the core of the north-central part. Quartz and K-feldspar increase toward the core of the pluton, whereas hornblende, biotite and color index decrease. /Abundances of $SiO_2$and $K_2O$$_2$O increase toward the core according to the variation in quartz and K-feldspar, whereas those of MnO, CaO, $TiO_2$, $Fe_2O_3$, MgO and $P_2O_5$ decrease corresponding to the variation in mafic and accessaries. The compositional zonation resulted from fractional crystallization involving downward settling of earlier crystals, accompanied by upward movement of melt and volatiles, and followed by accessary marginal accretion of crystalline material in the magma to the marginal part. Although a little crustal contamination by the wall rock is recognized from the isotope data, the contamination is not only dominated over but also appropriate for forming the compositional variation in the pluton.

• Restorative Dentistry and Endodontics
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• v.40 no.4
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• pp.255-261
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• 2015

Objectives: The aim of this study was to evaluate the effect of three different drinks on the color parameters of four different restorative materials. Materials and Methods: Three different composites (Filtek Ultimate Universal Restorative, Filtek Ultimate Flowable, and Filtek Silorane, 3M ESPE) and a polyacid-modified composite resin material (Dyract XP, Dentsply DeTrey GmbH) were evaluated. Eighty-four disc-shaped specimens of 8 mm in diameter and 2 mm in thickness were prepared (n = 21 each). Color coordinates ($L^*a^*b^*$, ${\Delta}L^*$, ${\Delta}a^*$, ${\Delta}b^*$, and ${\Delta}E^*$) were measured using a $V{\dot{I}}TA$ Easyshade Compact ($V{\dot{I}}TA$ Zahnfabrik) after 24 hr of storage (baseline) and after 30 day of storage in three different beverages of black tea, Coca cola, or water (control) (n = 7). In each beverage, the specimens were stored three times a day, one hr each, for 30 day. The color changes (${\Delta}E$) were calculated and were analyzed by Kruskal-Wallis and Dunn multiple comparison test. Results: The color difference (${\Delta}E^*$) of the resin materials ranged between 1.31 and 15.28 after 30 day of immersion in the staining solutions. Dyract XP in Coca cola ($15.28{\pm}2.61$) and black tea ($12.22{\pm}2.73$) showed the highest mean ${\Delta}E^*$ value after 30 day, followed by Filtek Ultimate Universal Restorative ($5.99{\pm}1.25$) and Filtek Ultimate Flowable ($4.71{\pm}1.40$) in black tea (p < 0.05). Conclusions: The compomers displayed unacceptable color changes at the end of 30 day in all beverages. Among resin composites, the silorane based composite exhibited relatively good color stability than the others. Filtek Ultimate Universal Restorative and Filtek Flowable showed similar color changes in all beverages.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.91-91
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• 2018

The Rosa multiflora, a well-known plant belonging to Rosacea, is widely used in orthodox medicine in worldwide. However, its biological activity as a functional ingredient for cosmetic products have not yet been studied. Accordingly, an investigation of the above mentioned atrributes was performed on a 50% ethanol extract of Rosa multiflora. The antioxidant activities were determined by DPPH. Additionally, the contents of total phenols and flavonoids were analyzed. Also, the phenolic compounds were detected using HPLC. The melanogenesis regulatory effect was evaluated using melanin content and cellular tyrosinase activity in B16F10 melanoma cells. The elastase inhibitory activity assay was performed for anti-wrinkle effect. The antimicrobial activity was assessed using the disc diffusion assay. The DPPH radical scavenging ability, denoted by the $SC_{50}$ value was found to be $123.1{\mu}g/ml$, whereas that of positive control (ascorbic acid) was $27.5{\mu}g/mL$. The content of total polyphenol and flavonoid content were 202 mg/g and 86.77 mg/g, respectively. In addition, astragalin and gallic acid were identified in the extract. Also, the ethanol extract significantly inhibited ${\alpha}$-MSH-induced melanogenesis in B16F10 cells. For anti-wrinkle effect, elastase inhibition activity of the ethanol extract was 53.2% at a concentration of $100{\mu}g/ml$. The antimicrobial activity of the extract against S. aureus and E. coli was observed to be 0.5 - 5%, and no significant activity was noted against C. albicans. Therefore, the ethanol extract of Rosa multiflora can be used effectively for development of functional cosmetic materials.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.2
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• pp.143-153
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• 2006

Temporomandibular joint(TMJ) ankylosis is characterized by the formation of bony or fibrous mass, which replaces the normal articulation. Ankylotic block formation causes reduction of mandibular mobility, particularly hindering mouth opening, due to a mechanical block of the condylar head in its roto-transfatory motion. Surgery in TMJ ankylosis treatment entails complete ankylotic block removal and subsequent arthroplasty, possibly with autologous tissue between articular surfaces or heterologous material to restore the anatomic structure and normal function. Temporalis myofascial flap holds great promise for the reconstruction of various maxillofacial defects. In more recent years, a pedicled temporalis myofascial flap has been advocated in TMJ ankylosis surgery. Advantages of the temporalis myofascial flap in TMJ reconstruction include close proximity to the TMJ, adequate blood supply from the internal maxillary artery, and its attachment to the coronoid process, which provides movement of the flap during function, simulating physiologic action of the disc. This study evaluated 8 patients(11 TMJs) affected by TMJ ankylosis. All patients underwent surgical treatment of the removal of the ankylotic block and subsequent interpositional arthroplasty with temporalis myofascial flap. Bilateral TMJ ankylosis was observed in 3 patients(6 TMJs), right-sides in 3 patients, left-sided in 2 patients. Epipathogenesis was traumatic in 6 patients(8 TMJs), ankylosing spondylitis in 2 patients(3 TMJs). In 3 patients coronoidotomy was underwent. Average follow-up was 16.8 months after surgery, with a range of 7 to 28 months. No patients underwent additional TMJ procedures after the temporalis myofascial flap. All patients showed a distinctive improvement both in articular functionality and symptoms. We found that temporalis myofascial flap is very valuable in reconstruction of TMJ ankylosis.

• The Journal of Advanced Prosthodontics
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• v.7 no.1
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• pp.69-75
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• 2015

PURPOSE. To compare the shear bond strength of various veneering materials to grade II commercially pure titanium (CP-Ti). MATERIALS AND METHODS. Thirty specimens of CP-Ti disc with 9 mm diameter and 10 mm height were divided into three experimental groups. Each group was bonded to heat-polymerized acrylic resin (Lucitone 199), porcelain (Triceram), and indirect composite (Sinfony) with 7 mm diameter and 2 mm height. For the control group (n=10), Lucitone 199 were applied on type IV gold alloy castings. All samples were thermocycled for 5000 cycles in $5-55^{\circ}C$ water. The maximum shear bond strength (MPa) was measured with a Universal Testing Machine. After the shear bond strength test, the failure mode was assessed with an optic microscope and a scanning electron microscope. Statistical analysis was carried out with a Kruskal-Wallis Test and Mann-Whitney Test. RESULTS. The mean shear bond strength and standard deviations for experimental groups were as follows: Ti-Lucitone 199 ($12.11{\pm}4.44$ MPa); Ti-Triceram ($11.09{\pm}1.66$ MPa); Ti-Sinfony ($4.32{\pm}0.64$ MPa). All of these experimental groups showed lower shear bond strength than the control group ($16.14{\pm}1.89$ MPa). However, there was no statistically significant difference between the Ti-Lucitone 199 group and the control group, and the Ti-Lucitone 199 group and the Ti-Triceram group. Most of the failure patterns in all experimental groups were adhesive failures. CONCLUSION. The shear bond strength of veneering materials such as heat-polymerized acrylic resin, porcelain, and indirect composite to CP-Ti was compatible to that of heatpolymerized acrylic resin to cast gold alloy.

• Archives of Plastic Surgery
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• v.33 no.1
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• pp.13-20
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• 2006

Alginate, which is isolated from brown seaweed, is a bioabsorbable long chain polysaccharides, ${\beta}$-D-mannuronic acid and ${\alpha}$-L-guluronic acid. The authors produced alginates and alginate-colllagen as a disc form. Then, to evaluate the efficacy of alginate and alginate-collagen complex as a wound healing material, three full-thickness skin defects of 2 cm in diameter were made at the back of the New Zealand white rabbits. Three groups of dressing materials-alginate, alginate-collagen complex and vaseline gauze as control group - were applied on the wound and the results were evaluated grossly and histopathologically. The authors compared gross findings of sizes of healed wound, wound epithelization and wound contraction by tracing the remaining wound area at 5th, 10th, 15th, 20th, 25th day after wound introduction, and wound biopsy was performed at 3rd, 7th, 14th, 21st day, respectively. Alginate and alginate-collagen complex showed statistically higher percentage of wound contraction and wound healing compared to control group(p<0.05). Alginate-collagen complex showed statistically higher percentage of wound contraction, epithelization and wound healing compared to alginate alone. In conclusion, the result suggests that alginate has a good effect of wound healing and that alginate-collagen complex is more effective in wound healing than alginate alone.