• Bulletin of the Society of Naval Architects of Korea
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• v.22 no.1
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• pp.45-53
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• 1985

For the analysis of vertical vibrations of a ship's hull, the Timoshenko beam analogy is accepted up to seven or eight-node modes provided that the system parameters are properly calculated. As to the shear coefficient, it has been a common practice to apply the strain energy method or the projected area method. The theoretical objection to the former is that it ignores lateral contraction due to Poisson's ratio, and the latter is of extreme simplifications. Recently, Cowper's and Stephen's shear coefficient formulas have drawn ship vibration analysts' attentions because these formulas, derivation of which are based on an integrations of the equations of three-dimensional elasticity, take Poisson's ratio into account. Providing computer programs for calculation of the shear coefficient of ship sections modeled as thin-walked multicell sections by each of the forementioned methods, the authors calculated natural vibration characteristics of a bulk carrier and of a container ship by the transfer matrix method using shear coefficients obtained by each of the methods, and discussed the results in comparision. The major conclusions resulted from this investigation are as follows: (1) The shear coefficients taking account of the effects of Poisson's ratio, Cowper's $K_c$ and Stephen's $K_s$, result in higher values of about 10% in maximum as compared with the shear coefficient $K_o$ based on the conventional strain energy methods; (a) $K_c/K_o{\cong}1.05\;and\;K_s/K_o{\cong}1.10$ for ships having single skin side-shell such as a bulk carrier. (b) $K_c/K_o{\cong}1.02\;and\;K_s/K_o{\cong}1.05$ for ships having longitudinally through bulkheads and/or double side-shells in the portion of the cargo hod such as a container carrier. (2) The distributions of the effective shear area along the ship's hull based on each of $K_o,\;K_c\;and\;K_s$ are similar each another except the both end portions. (3) Natural frequencies and mode shapes of the hull based on each of $K_c\;and\;K_s$ are of small differences as compared each other. (4) In cases of using $K_c\;or\;K_s$ in ship vibration analysis, it is also desirable to have the bending rigidity be corrected according to the effective breadth concept. And then, natural frequencies and mode shapes calculated with the bending rigidity corrected in the above and with each of $K_o,\;K_c\;and\;K_s$ result in small differences as compared each another. (5) Referring to those mentioned in the above (3) and (4) and to the full-scale experimental results reported by Asmussen et al.[17], and considering laboursome to prepare the computer input data, the following suggestions can safely be made; (a) Use of $K_o$ in ship vibration analysis is appropriate in practical senses. (b) Use of $K_c$ is appropriate even for detailed vibration analysis of a ship's hull. (6) The effective shear area based on the projected area method is acceptable for the two-node mode.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.36 no.1
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• pp.71-77
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• 2010

The water fern Azolla belongs to the Azollaceae and forms a symbiotic association with a $N_2$-fixing cyanobacterium, referred to as Anabaena azollae, and this association has currently been demonstrated to have potential as a nitrogen source for rice production. Because of that, Azolla fern has been used not only as organic manure in southern China and northern Vietnam for a long time but also as food for animate creatures in the underwater and decontaminant in the water. However, the phenolic compounds and active materials of Azolla have not been examined in detail in the past studies. In the present study, anti-oxidant ability test and experiment to find a particular active material of Azolla imbricata and Azolla imbricata fraction (AIF) were performed. In anti-oxidant test such as DPPH test and lipoxygenase inhibition test, the value of test represented high activities compared with authentic sample - green tea and NDGA (nordihydroguaiaretic acid). In MMP-1 test, related to collagen protection and elasticity of skin, its inhibitory effect was measured over 75 %, and the phenolic compounds of AIF related with this activity were confirmed luteolin derivatives by using FT-IR spectroscopy, element analyzer (EA) and Liquid chromatography-MASS spectroscopy.

• Journal of Naturopathy
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• v.8 no.2
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• pp.63-70
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• 2019

Purpose: The purpose of this study was to investigate whether Qihyul-therapy was effective against subjects of bad Qihyul circulation who had narrowed muscles of the buttocks, a distorted body shape, or pain. Methods: Qihyul-therapy used. Results: The muscles of the buttocks remained almost untouched. The elasticity of the muscles restored. The skin tone brightened, and the anal muscle strengthened after Qihyul-therapy. The subject's body was shifted to the right by -7°. The right arm was about 6 cm longer than the left arm. But after correction, the right arm was about 5 cm shorter. The distorted body was almost balanced. After neck and shoulder correction, the distance between the collarbone and neck was 7~10 cm wider. After the pelvic correction, the pain in the buttocks was relieved, and the position of the hip joint returned correctly. The right leg that was turned 45° to the left was corrected, and the length became the same. Subjects had no knees attached, their right knees were up 5 cm above the left, and their ankles bent at an angle of 30 ° relative to the left, but after correction, the knees of the two legs stably attached. The height of the knee became the normal angle. Conclusion: If the Qihyul-therapy, the spine correction Qihyul-exercise and the pelvic correction Qihyul-exercise performed steadily, the deformed body shape restored adequately, and it is useful to prevent and cure related diseases by alleviating the pains.

• Food Science and Preservation
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• v.24 no.1
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• pp.93-99
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• 2017

Collagen synthesis is decreased and matrix metalloproteinase-1 (MMP-1) levels are increased in naturally aged human skin, and these alterations cause changes such as skin wrinkling and decreased elasticity. As a part of our ongoing search for bioactive ingredients, MMP-1 inhibitory and type-1 procollagen synthesis inducing activities of aqueous methanolic extract of manufactured gambir product from Uncaria gambir were investigated in in vitro bioassay systems. In addition, total phenolic contents were quantified using a spectrophotometric method. Among tested samples, 40% MeOH eluate from 80% methanolic extract of manufactured U. gambir using open column chromatography packed with Diaion HP-20 resin showed significant MMP-1 inhibitory activities with an $IC_{50}$ value of $15.6{\pm}1.3{\mu}g/mL$. Furthermore, type-1 procollagen synthesis promoting property of 40% MeOH eluate ($IC_{50}$ value; $6.9{\pm}0.7{\mu}g/mL$) from 80% methanolic extract of manufactured gambir was higher than other eluates. Additionally, the present investigation revealed that 40% MeOH eluate of manufactured gambir product contained a high level of total phenolic compounds. The result suggests a distinct relationship between anti-wrinkle activity and total phenolic contents, and manufactured gambir product could be considered a new effective source of natural bioactive ingredients. Systematic investigation of manufactured gambir product will be performed for further development of its biological properties.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.1
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• pp.80-98
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• 2002

Taxus cuspidata Sieb selected cultivation as drug, food and decorative plant in Kyong-gi province in Korea. As a manufacturing method, there were extracted from 250g of dried-leaf and 300g of dried-stem with each 200g of BG, PG and water (to 100) mixing for 72 hour at 50$\pm$5$\^{C}$ and then they were filtered by 400-mesh filter. Appearance of extract of leaves was slight brown, pH=5.3$\pm$0.5, gravity was 1.012$\pm$0.05, and a reflective index was 1.375$\pm$0.05. And appearance of extract of stems was slightly dark brown, pH=5.4$\pm$0.5, gravity was 1.016$\pm$0.05, and a reflective index was 1.358$\pm$0.05. It was extracted oil from Taxus seed. Gravity was 0.922$\pm$0.05 and it should be obtained the 27.0$\pm$0.5% of yield. The molecular weight of polysaccharide was about 50,000 to 300,000 dalton and contained 5.0$\pm$1.2% of yield from Taxus fruit. The determinations of total polyphenols in measuring spectropotometer got 0.563% in leaves, and 0.325% in stems, whereas the quantitives of total tannins got 0.054% and 0.037%, respectively. As the effects in Cosmetics by DPPH-method, the antioxidative activities were very strong that the inhibitory ratio showed 75% in leaves and 64% in stems compared with 52% in greentea extract. These are more effective than other plant extracts. The increasing ratio of collagen synthesis rate on the activating fibroblast for extracts of Taxus cuspidata Sieb showed 54.16% (stems) and 33.18% (leaves), To improve the skin elasticity, PPE(porcine pancreatic elastase)-inhibitory activities were strongly effective as 13,7% (stems), 23.5% (leaves) and 66%(seed). Anti-inflammatory acitvity of seed oil was very the above 41% stronger than SG was 24% of anti-Inflammatory as a control sample.