• Journal of Pharmaceutical Investigation
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• v.38 no.1
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• pp.1-8
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• 2008

Planetary ball mill was used to decrease and control the particle size of excipients. The effects of the weight of sample and the revolution number of mill, and grinding time on the particle size of the ground sample were analyzed by response surface methodology. The optimum conditions for the milling of microcrystalline cellulose were 38.82 g of the weight of sample and 259 rpm of the revolution number of mill, and 45 minutes of grinding time. The predicted value of the particle size at the these conditions was $19.02{\mu}m$, of which the experimental value at the similar conditions was $18.68{\mu}m$. The tensile strength of tablets of single-component powders, such as microcrystalline cellulose, hydroxypropylmethyl cellulose and starch, binary mixtures and ground binary mixtures of these powder were measured at various relative densities. It was found that the logarithm of the tensile strength of the tablets was proportional to the relative density. A simple model, based upon Ryshkewitch-Duckworth equation that was originally proposed for porous materials, has been developed in order to predict the relationship between the tensile strength and relative density of ground binary tablets based on the properties of the constituent single-component powders. The validity of the model has been verified with experimental results for ground binary mixtures. It has demonstrated that this model can well predict the tensile strength of ground binary mixtures based upon the properties of single-component powders, such as true density, and the compositions. When the tensile strength of the mixture of microcrystalline cellulose hydroxypropylmethyl cellulose (90:10) and the ground mixture of them were compared, the tensile strength of the ground mixture decreased widely from 45.3 to 5.6% compared to the mixture in case the relative density of tablets was in the range of $0.7{\sim}0.9$. When the tensile strength of the mixture of microcrystalline cellulose starch (80:20) and the ground mixture of them were compared, the tensile strength of the ground mixture decreased widely from 31.0 to 11.6% compared to the mixture in case the relative density of tablets was in the range of $0.7{\sim}0.9$.

• Biomolecules & Therapeutics
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• v.21 no.3
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• pp.246-250
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• 2013

We previously reported that the extract from cuttlebone (CB) has wound healing effect in burned lesion of rat. In present study, the main component of CB extract was analyzed and its wound healing activity was evaluated by using in vitro acute inflammation model. The extract of CB stimulated macrophages to increase the production of TNF-${\alpha}$. The extract also enhanced the production of TGF-${\beta}$ and VEGF, which were involved in angiogenesis and fibroblast activation. The treatment with CB extract enhanced proliferation of murine fibroblast. CB extract also induced the activation of fibroblast to increase the secretion of matrix metalloproteases 1 (MMP1). The constituent of CB extract which has wound healing activity was identified as chitin by HPLC analysis. The mechanism that the CB extract helps to promote healing of burned lesion is associated with that chitin in CB extracts stimulated wound skins to induce acute inflammation and to promoted cell proliferation and MMP expression in fibroblast. Our results suggest that CB or chitin can be a new candidate material for the treatment of skin wound such as ulcer and burn.

• Journal of the Korean Ceramic Society
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• v.43 no.5 s.288
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• pp.270-276
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• 2006

LSGM(($La_xSr_{1-x})(Ga_yMg_{1-y})O_3$) electrolyte is known to show very serious interfacial reaction with other unit cell components, especially with an anode. Such an interfacial reaction induced the phase instability of constituent component and deterioration of the unit cell performance, which become the most challenging issues in LSGM-based SOFCs. In this study, we fabricated LSGM($La_{0.8}Sr_{0.2}Ga_{0.83}Mg_{0.17}O_x$) electrolyte supported-type cell in order to avoid such interfacial problem by lowering the heat-treatment temperature of the electrode fabrication. According to the microstructural and phase analysis, there was no serious interfacial reaction at both electrolyte/anode and electrolyte/cathode interfaces. Moreover, from the electrochemical characterization of the unit cell performance, there was no distinct deterioration of the open cell voltage as well as an internal cell resistance. These results demonstrate the most critical point to be concerned in LSGM-based SOFC is either to find a proper electrode material which will not give any interfacial reaction with LSGM electrolyte or to properly adjust the processing variables for unit cell fabrication, to reduce the interfacial reaction.

• The Research Journal of the Costume Culture
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• v.14 no.1
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• pp.79-92
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• 2006

This study was purposed to present the basic data on the elderly women's somatotype to develop new briefs design with high body-adaptability. The subjects were 115 elderly women in the 60s and 70s and the factor analysis for 32 directly measured values of the body parts was carried out to sort out the constituent factors of the elderly women's bodies, and finally 4 factors were decided. The first factor was the thickness of the trunk and the degree of the obesity in the center of the width, thickness and circumference. The second factor is the perpendicular size of the body with high loads on the longitudinal direction of the body. The third factor was the leg shape. The last factor was the degree of the sagging hip. The elderly women's somatotype was classified into 3 types. The first type was the 'mean somatotype' with the biggest height and the longest lower half body of the three types. The second type was the 'obese somatotype' with the mean height and length of the lower body and with the largest circumference and width. The last type was the 'skinny somatotype' with the smallest values of all the items in the perpendicular size and the degree of the obesity.

• Journal of Korean Association for Spatial Structures
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• v.9 no.1
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• pp.61-68
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• 2009

This paper is concerned with the investigation of the structural behavior of waffle structure. Parametric variation on waffle floor thickness, main beam depth and column sizes are imposed to study the effects on mode shapes and natural frequencies of waffle structures. Comparisons between FEM models using shell and 3D-solid elements have also been made. The analysis result has shown that the mode frequencies increase with i) increase in main beam depth at level 2 and ii) decrease in waffle slab thickness at level 3. Both 3D and 2D model shown similar mode shapes. Besides, there is a consistent difference in mode frequencies between 3D and 2D model ranging from 25% to 36%.

• Journal of Korea Water Resources Association
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• v.38 no.6 s.155
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• pp.505-515
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• 2005

Two representative river water quality models have been compared in this paper. The steady water quality model, QUAL2E, and the unsteady model, CE-QUAL-RIV1, have been chosen for comparative simulations. Under same reaction coefficients and boundary conditions, the water quality of the Geum river below the Daechung dam has been simulated using two different models, and the water quality equations are compared each other. Since basic model algorithm is very close, the input data required for model run is very similar. Upon the simulation under steady condition, the results of two models show very good agreement especially for BOD, DO, and $NH_3-N$, while the results of specific constituent such as dissolved P is quite different. As a result, dominant water quality parameters to compute each corresponding water quality variables are summarized and tablized through the sensitivity analysis.

• Korean Journal of Pharmacognosy
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• v.52 no.3
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• pp.192-201
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• 2021

Dangguisu-san (DGSS) is widely known traditional herbal medicinal formula in Korea for treatment of traumatic injury by traffic accident, ecchymosis, abdominal distension and anti-thrombosis of blood. This study was conducted to develop the simultaneous analyze method using high performance liquid chromatography (HPLC) and examine the effect of anti-inflammatory activity of DGSS-dry extract (DGSS-DE) and DGSS-mix extract powder (DGSS-MEP). Physicochemical characteristics of DGSS-DE and DGSS-MEP showed that there is no significant difference in pH, titratable acidity, total soluble solid content and browning degree except for color value (L, a, b). 15 functional constituents of DGSS were identified and the correlation coefficient values of DGSS-DE and DGSS-MEP were conformed 0.950. Also, DGSS-DE and DGSS-MEP significantly decreased the secretion of nitric oxide (NO), prostaglandin E₂ (PGE₂), interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) through inhibited expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), IL-1β, IL-6, and TNF-α. From these result, DGSS-MEP showed similar chemical composition and anti-inflammatory effect to DGSS-DE. Therefore, DGSS-DE and DGSS-MEP may be useful as potential source of drug to prevent inflammation.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.4
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• pp.397-407
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• 2022

Mineralogical analysis of the bedrock of the Gobi Desert in southern Mongolia, the source of Asian dust, was conducted to trace the geological origin of the constituent minerals of Asian dust. The bedrock of the source of Asian dust consists of Paleozoic volcanics and volcaniclastic sedimentary rocks, Paleozoic granitic rocks, and Mesozoic sedimentary rocks. Paleozoic volcanics and volcaniclastic sediments lithified compactly, underwent greenschist metamorphism, and deformed to form mountain ranges. Mesozoic sedimentary rocks fill the basin between the mountain ranges of Paleozoic strata. In comparison to Paleozoic volcanic and sedimentary rocks, Mesozoic sedimentary rocks have lower contents of chlorite and plagioclase, but high contents of clay minerals including interstratified illite-smectite, smectite, and kaolinite. Paleozoic granites characteristically contain amphibole and biotite. Compared with the mineral composition of bedrock in source, Asian dust is a mixture of detrital particles originating from Paleozoic and Mesozoic bedrocks. However, the mineral composition of Mesozoic sedimentary rocks is closer to that of Asian dust. Less lithified Mesozoic sedimentary rocks easily disintegrated to form silty soils which are deflated to form Asian dust.

• Economic and Environmental Geology
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• v.36 no.6
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• pp.415-429
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• 2003

This study was objected to identify the difference of water quality and the characteristics of water contamination in adjacent bed-rock areas of Upper Hwajeonni and Guryongsan Formations in Miwon, Choongchungbuk-do, Korea. Water samples showed mainly (Ca, Mg)-$HCO_3$ type in Upper Hawjeonni Formation and (Ca, Mg)-$SO_4$ and (Ca, Mg)-$HCO_3$ types in Guryongsan Formation indicating the enrichment of $SO_4$ in major compositions. Groundwater quality could be divided into two groups based on the major weathering processes, implied by the ratio of bicarbonate to silica. Carbonate-silicate weathering predominates in Upper Hwajeonni Formation, and silicate weathering in Guryongsan Formation. Stream-water quality also appeared to be controlled by water-rock interaction. Cluster analysis identified three groups of groundwater and four groups of stream-water with distinctive geochemical characteristics. The results of factor analysis indicated that the levels of each chemical constituent in water samples derived from both natural weathering reactions and anthropogenic contamination sources. To delineate the pollution potential of water resources, Modified Pollution Index(M.P.I.) was developed. M.P.I. scores of water samples ranged from -0.08 to 0.18, with mostly positive along the rock quarry in Guryongsan Formation areas. M.P.I. scores appeared to be a useful predictor of metal contamination of water resources.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.12
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• pp.1981-1989
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• 2008

Different people buy the same or similar products for different reasons. Benefit segmentation attempts to understand these differences by grouping together people who assign a similar level of importance to the same attributes. We focused on identifying market segments for knit fabrics by comparing the relative attribute preference for knit fabrics according to segmented clusters, and testing to establish if there were significant differences between the preferences of clusters. Three consumer segments emerged, and there were three clusters with different ideal knit profiles: a preferred wool group, a preferred acrylic group, and a preferred long stitch length group. The preferred wool group and the preferred acrylic group rated the mixture ratio as the main attribute that determined their preference, followed by the stitch length. The preferred long stitch length group considered stitch length as being the most important attribute, followed by the mixture ratio. The difference in the preferences for the mixture ratio and stitch length of knit fabrics was the highest between the three clusters, The preferred wool group preferred a knit fabric that has a greater wool mixture ratio and a short stitch length, and the preferred acrylic group and long stitch length group preferred a knit fabric that had a higher acrylic mixture ratio and a short stitch length.