• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.11
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• pp.1123-1129
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• 2015

A pair of two-way valves typically is used in automotive washing machines, where the water flow direction is frequently reversed and highly pressurized clean water is sprayed to remove the oil and dirt remaining on machined engine and transmission blocks. Although this valve system has been widely used because of its competitive price, its application is sometimes restricted by surging effects, such as pressure ripples occurring in rapid changes in water flow caused by inaccurate valve control. As an alternative, one three-way reversing valve can replace the valve system because it provides rapid and accurate changes to the water flow direction without any precise control device. However, a cavitation effect occurs because of the complicated bottom plug shape of the valve. In this study, the cavitation index and percent of cavitation (POC) were introduced to numerically evaluate fluid flows via computational fluid dynamics (CFD) analysis. To reduce the cavitation effect generated by the bottom plug, the optimal shape design was carried out through a parametric study, in which a simple computer-aided engineering (CAE) model was applied to avoid time-consuming CFD analysis and difficulties in achieving convergence. The optimal shape design process using full factorial design of experiments (DOEs) and an artificial neural network meta-model yielded the optimal waist and tail length of the bottom plug with a POC value of less than 30%, which meets the requirement of no cavitation occurrence. The optimal waist length, tail length and POC value were found to 6.42 mm, 6.96 mm and 27%, respectively.

• Elastomers and Composites
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• v.34 no.2
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• pp.135-146
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• 1999

The thermal degradation kinetics of SBR and tire were studied using a conventional thermogravimetric analysis in the stream nitrogen at a heating rate of 5, 10, 15, $20^{\circ}C/min$, respectively. Thermogravimetric curves and their derivatives were analyzed using various analytical methods to determine the kinetic parameters. The degradation of the SBR and tire was found to be a complex process which has multi-stages. The Friedman method gave average activation energies for the SBR and tire of 247.53kJ/mol and 230.00kJ/mol, respectively. Mean-while, the Ozawa method Eave 254.80kJ/mol and 215.76kJ/mol. It would appear that either. Friedman's differential method or Ozawa's integral method provided satisfactory mathematical approaches to determine the kinetic parameters for the degradation of the SBR and tire. Approximately 86% and 55% of oil products were obtained at a final temperature of $700^{\circ}C$ and a heating rate of $20^{\circ}C/min$ for the SBR and tire respectively.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.369-375
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• 2004

In this study, liquid crystalline (LC) is formed using Gemini surfactant (GS) type and moisturizing effect in vivo is measured. $3.0\;wt\%$ of sodium dicocoyl ethylene diamine (PEG)-15 sulfate (SCD-PEG-15S) is used as GS and $4.0\;wt\%$ of hydrogenated dimer acid esters (HDAE) as booster. For stabilizers, $2.0\;wt\%$ of behenyl alcohol (BA) and $1.0\;wt\%$ of Iyso-lecithin (LyL) are utilized. It is stabilized in pH from 4.0 to 10.5 and the best condition is in pH 6.5. The value of viscosity is $8,000\pm500$ cP. The most excellent particles are formed within the range of 4.0 to 15.5 um. Formed LC is observed around LC particles using polarization microscope. It is also observed that lamellar gel network structure is formed around LC particles. Moisturizing effect is improved by $13.6\%$ (P<0.05) compared to control when measured 30 min later after coating samples. After 1 h, moisturizing effect is improved by 1$12.6\%$ (P<0.05) than control while showing $28.3\%$ (P<0.05) of improvement after 4 h. These results may be caused from that manufactured LC forms lamellar structure so that it has better water-holding ability and absorbance of oil increases. This formula could be utilized by delivery system (DS) on skin so that this technology can be applied for manufactuing pharmaceuticals and cosmetics.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.3
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• pp.247-255
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• 2016

In order to select a strain that forms a Biocellulose (BC), strain producing acetic acid was selected from commercially available kombucha. Through SM broth it was confirmed that the strain is a gram negative bacteria in the form of rods having no motility through a phase contrast microscope. The result of phylogenetic inference analysis based on 16S rDNA sequence analysis for the identification of strains was most closely related to Gluconobacter uchimurae (G. uchimurae) and was named G. uchimurae GYS15 strain. The strain showed the highest degree of growth when cultured for 14 days under the conditions of pH 5 and $25^{\circ}C$. Moreover, it showed the highest degree of growth in a Glucose addition disaccharide as the optimum carbon source sucrose and fructose. Also, 0.5% NaCl, upon the addition of Malto extract, showed the highest degree of growth. Based on investigation by the optimum growth conditions to confirm the physical properties of BC obtained by culturing G. uchimurae GYS15 strains. The surface structure was observed through an scanning electron microscope (SEM) showed a high networks structure. It until $8.6{\pm}0.38$ times when the water holding capacity is re-absorbed and re-absorbed holding oil up to $6.6{\pm}0.51$ times confirmed. In conclusion, using these material properties, it was possible to confirm the possibility of a variety of cosmetic materials and mask pack materials.

• The Korean Journal of Zoology
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• v.31 no.3
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• pp.191-206
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• 1988

Chick embryos which have received a single injection of the organophosphate compound,malathion (0.1 mg, 0.5 mg, 1.0 mg or 2.0 mg in 0.05 ml of corn oil) via the yolk sac at certain times (2 daya, 4 days or 6 days after incubation) have been investigated. After 9 days of incubation, chick embryos were harvested to investigate the effects of malathion on the development of cerebrum morphologically and biochemically. The effects of simultaneous injection of malathion and nicotinamide were also compared. On ultrastructural examination, neurons in cerebral cortex showed to be inhibited in their differentiation by malathion; nuclear irregularity, swelling of endoplasmic reticulum, and cytoplasmic vacuoles were observed. On cytochemical study of acetylcholinesterase(AChE) by electron microscope, the positive reaction products of this enryme were localized at the membrane of nucleus and endoplasmic reticulum of neurons. Inhibition of AChE activty was severe in groups treated with relatively low doses, which was consistent with the results of spectrophotometric analysis. The activity of lactate dehydrogenase(LDH) of cerebrum in groups treated with malathion was higher than that of the control group. The nicotinamide adenine dinucleotide(NAD) content of chick embruo treated with malathioti decreased significantly, and nicotinamide coinjection raised the NAD level as compared with the control group, thus preventing malathion-induced momhological alteration. In conclusion, it is suggested that malathion changes the ultrastructure of differentiating neurons and alters some enzyme activities in chick embryo cerebrum, and the severity of which is consistently dose-or age-dependent.

• Food Science and Preservation
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• v.9 no.4
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• pp.400-405
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• 2002

Herbs are widely used as a source of tea and otherwise such as botanical medicine, essential oil for perfumes, cosmetics, and food spices. This study was carried out to investigate the characteristics of herb tea prepared with lavender, rosemary, mint, thyme and sage cultivated in korea. Approximate composition were as follows : crude protein 1.4∼17.5%, crude fat 6.1∼15.8%, sugars 43.5∼61s%, crude ash 7.7∼10.7%. Minerals contents of Ca ranged 707∼1763mg%, P 234 ∼513mg%, K 2,391∼3,430mg%, and Mg 361∼573mg%. Vitamins were $\beta$ -Carotene 6.9∼27.7mg%, B$_1$, 0.34∼0.62mg%, B$_2$1.37 ∼2.52mg%, niacin 5.3∼8.8mg%, and C 102∼111mg%. The changes of chromaticity a and b, pH, and sugar content of the herb tea at the different temperatures were decreased 80$\^{C}$ and 100$\^{C}$ in comparison to 60$\^{C}$ but increased chromaticity L. In the result of sensory test of the processed herb tea was more preferred than the market goods.

• Food Science and Preservation
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• v.19 no.3
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• pp.455-461
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• 2012

Obesity, a strong risk factor for the development of chronic diseases, is characterized by an increase in the number and size of adipocytes differentiated from precursor cells, preadipocytes. Recent research suggests that increased reactive oxygen species (ROS) production in 3T3-L1 adipocyte facilitates adipocyte differentiation and fat accumulation. This study was to investigate whether reduced ROS production by Sargassum micracanthum extract (SME) could protect the development of obesity through inhibition of adipogenesis. 3T3-L1 preadipocytes were treated SME for up to 8 days following standard induction of differentiation. The extent of differentiation reflected by amount of lipid accumulation and ROS production was determined by Oil red O staining and nitroblue tetrazolium (NBT) assay. Treatment of SME significantly inhibited ROS production and adipocyte differentiation that is depend on down regulation of NADPH oxidase 4 (NOX4), a major ROS generator, and peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) and CCAAT/enhancer-binding protein alpha ($C/EBP{\alpha}$), a key adipogenic transcription factor. These results indicate that SME can inhibit adipogenesis through a reduced ROS level that involves down-regulation of NOX4 expression or via modulation of adipogenic transcription factor.

• Korean Journal of Plant Resources
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• v.28 no.1
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• pp.79-92
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• 2015

This study was conducted during two separate periods, from April to December 2008 and from April to November 2013, to identify the folk plants growing in Jeollanam-do which are used daily. A total of 1,200 questionnaires were distributed to 120 residents living in 14 counties and cities. From the results of the survey, 172 taxa of folk plants (77 families, 153 genera, 154 species, 2 subspecies, 14 varieties, and 2 forma) were identified. By regions, the city of Suncheon yielded 82 taxa, followed by 67 taxa from Gurye county, 65 taxa from Hampyeong county, 64 taxa from Jangseong county, 62 taxa from city of Naju, and 61 taxa from Jangheung county. Uses of the identified folk plants were: as edibles (117 taxa), for medicinal purposes (66 taxa), tea (15 taxa), for starch (6 taxa) for vegetable fat and oil (3 taxa), for nectar (2 taxa), for sap (2 taxa), for spice (2 taxa), for aroma (1 taxa), for fiber (1 taxa), and others (14 taxa). Thus, edible and medicinal uses of the plants appeared higher than other uses. The consistency of the local names of plants with the standard botanical nomenclature was 23.2% (40 taxa), while the proportion of local plant names analogous to the standard names was 18.6% (32 taxa). The consistency of the local plant names with the same plants in different cities and counties was 28.5% (49 taxa) and the proportion of local plant names analogous to each other in this category was 25.6% (44 taxa). Therefore, 54% of the folk plants growing in Jeollanam-do are known by location specific names. The usage types of the local folk plants were mostly collected through verbal communications.

• Journal of Korean Medicine Rehabilitation
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• v.21 no.1
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• pp.79-95
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• 2011

Objectives : This study was to investigate the antiarthritic effect of Hwallak-dan(Huoluo-dan) on the complete freund's adjuvant(CFA)-induced arthritis in Lewis rats. Methods : Arthritis was induced by intradermal injection of CFA into base of tail. Experimental groups divided into normal(n=10), control(n=10) and treated(n=10) group. Animals of control group received normal saline for twenty days, treated group received extracts Hwallak-dan(Huoluo-dan) for same duration, light mineral oil only injected non-arthritic rats were served as normal group. The incidence of arthritis and arthritic index were observed after treatment. Body weight, paw edema volume and thickness of ankle joint were measured at 0, 11, 14, 17, 20 days after treatment. White blood cell(WBC) counts in blood were analysed at 20 days after treatment and tumor necrosis $factor-{\alpha}(TNF-{\alpha})$, $interleukin-1{\beta}(IL-1{\beta}$), IL-6 contents in paw exudate were analysed by ELISA at 20 days after treatment. Histopathology on the ankle joint were performed at 20 days after treatment. Results : 1. Incidence of arthritis of treated group was 60% and control group was 100% at 20 days after treatment. 2. Arthritic index of treated group was significantly decreased compared with control group at 20 days after treatment. 3. Paw edema volume and thickness of ankle joint of treated group was significantly decreased compared with control group at 20 days after treatment. 4. Total WBC of treated group was significantly decreased compared with control group at 20 days after treatment. 5. Neutrophils of treated group was significantly decreased compared with control group at 20 days after treatment. 6. $TNF-{\alpha}$ content in paw exudate of treated group was significantly decreased compared with control group at 20 days after treatment. 7. $IL-1{\beta}$ content content in paw exudate of treated group was significantly decreased compared with control group at 20 days after treatment. 8. IL-6 content content in paw exudate of treated group was significantly decreased compared with control group at 20 days after treatment. 9. Histopathological arthritic index of treated group was significantly decreased compared with control group at 20 days after treatment. Conclusions : These results indicate that Hwallak-dan(Huoluo-dan) has inhibitory effect on the development and progression of CFA-induced arthritis in rats.

• Journal of Korean Medicine Rehabilitation
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• v.21 no.1
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• pp.97-114
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• 2011

Objectives : The object of this study is to observe the favorable anti arthritic effects of Sowhalrack-dan($Xi\check{a}ohu\acute{o}lu\grave{o}-d\bar{a}n$)(SWRD), which has been traditionally used in Korean medicine to treat rheumatoid arthritis on Freund's complete adjuvant(FCA) induced arthritic Wistar rats. Methods : Rheumatoid arthritis was induced by intradermal injection of FCA(10 mg in 1 ml paraffin oil 0.1 ml/rats). Each of 8 rats showing regular ankle circumferences per group were selected in 14 days after FCA treatment to confirm the induction of rheumatoid arthritis. 300, 150 or 75 mg/kg of SWRD was orally administered once a day for 14 days from 14 days after FCA treatments. Dexamethasone was intraperitoneally administered 15 mg/kg, once a day for 14 days from 14 days after FCA treatments. Rats were sacrificed after 14 days of continuous oral treatment of SWRD or intraperitoneal administration of dexamethasone, and changes were observed; the body weight, knee circumferences, gross arthritis score, inflammatory tissue $prostaglandin(PG)E_2$ levels and cartilage collagen, glucosaminoglycans compositions - chondroitin sulphate, heparin sulphate and hyaluronic acid in the present study. Results : As results of FCA treatment, classic rheumatoid arthritis featuring dramatical decreases on the body weights, cartilage collagen contents and bone glucosaminoglycans - chondroitin sulphate, heparin sulphate and hyaluronic acid contents. Also, it increases the knee circumferences, gross arthritis scores and inflammatory tissue $PGE_2$ levels. However, these changes from FCA induced rheumatoid arthritis were clearly reduced due to the dexamethasone and both two different dosages of SWRD, 300 and 150 mg/kg in the present study. Although FCA induced arthritis were more favorably inhibited by treatment of dexamethasone 15 mg/kg compared to SWRD 300 mg/kg, marked decreases of body weights were detected in dexamethasone 15 mg/kg treated rats. Conclusions : The results obtained in this study suggest that over 150 mg/kg of SWRD showed favorable anti-arthritic effects on the FCA induced arthritis mediated by suppression of $PGE_2$. However, detailed mechanism studies are needed with the screening of the biological active compounds in SWRD. Although FCA induced arthritis were more favorably inhibited by treatment of dexamethasone 15 mg/kg compared to SWRD 300 mg/kg, marked decreases of body weights were detected in dexamethasone 15 mg/kg treated rats, in the present study.