• Bulletin of the Society of Naval Architects of Korea
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• v.20 no.3
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• pp.17-20
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• 1983

There have been many investigations of predicting the added resistance of a ship in seaway since Havelock discussed this topic in 1937. Among these researches, Maruo's theoretical approach is known as the most consistent mathematical representation for added resistance of a ship in regular head sea. In his theory, the hull form of a ship is represented under the slender body approximation. But the motion responses which were used for the calculation of the added resistance have been obtained by using the strip method which is based on an approximation that the hull form may be expressed as set of two dimensional cylinder sections in longitudinal direction. Therefore two different methods for hull form representation were implicity used in Maruo's original work for the added resistance calculation. Utilizing the characteristics that hull forms are usually slender, Kan expressed the hull form as two dimensional cylinder at each station by using the Taylor series expansion for the length wise direction. Putting this idea into Maruo's original work, the added resistance can be obtained with the explicitly unique representation of the hull form. For the purpose of comparison the added resistance of a hull form(series 60, Cb=0.6) was calculated by using the motion response obtained by Shintani. The numerical result showes a good qualitative agreement with the experimental result by Sibul.

• Bulletin of the Korean Chemical Society
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• v.31 no.1
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• pp.133-139
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• 2010

Photoelectrocatalytic decolorization of methlene blue (MB) in the presence of two types of carbon nanotube/titania and yttrium-treated carbon nanotube/titania electrodes in aqueous solutions were studied under visible light. The prepared composite electrodes were characterized by X-ray diffraction, transmission and scanning electron microscopy, energy dispersive X-ray analysis, and photoelectrocatalytic activity. The photoelectrocatalytic performances of the supported catalysts were evaluated for the decolorization of MB solution under visible light irradiation. The results showed that yttrium incorporation enhanced the decolorization rate of MB. It was found that the photoelectrocatalytic degradation of a MB solution could be attributed to the combined effects caused by the photo-degradation of titania, the electron assistance of carbon nanotube network, the enhancement of yttrium and a function of the applied potential. The repeatability of photocatalytic activity was also tested. The presence of yttrium enhanced the hydrophillicity of yttrium-carbon nanotubes/titania electrode because more OH groups can be adsorbed on the surface.

• Environmental Engineering Research
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• v.24 no.4
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• pp.608-617
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• 2019

The adsorption of sulfamethoxazole (SMX) onto a NaOH-activated pine wood-derived biochar was investigated via batch experiments and models. Surprisingly, the maximum adsorption capacity of activated biochar for SMX (397.29 mg/g) was superior than those of pristine biochars from various feedstock, but comparable to those of commercially available activated carbons. Elovich kinetic and Freundlich isotherm models revealed the best fitted ones for the adsorption of SMX onto the activated biochar indicating chemisorptive interaction occurred on surface of the activated biochar. In addition, the intraparticle diffusion limitation was thought to be the major barrier for the adsorption of SMX on the activated biochar. The main mechanisms for the activated biochar would include hydrophobic, π-π interactions and hydrogen bonding. This was consistent with the changes in physicochemical properties of the activated biochar (e.g., increase in sp² and surface area, but decrease in the ratios of O/C and H/C).

• Child Health Nursing Research
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• v.13 no.4
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• pp.399-406
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• 2007

Purpose: This study was performed to test an obesity management program for elementary school children. The program was assessed by examining its effects on the obesity, dietary attitudes, dietary habits, and exercise habits. Methods: The participants were 65 elementary school children, of which 32 were assigned for the experimental group and 33 for the control group. The experimental group received an 8 weeks obesity management program. The outcome variables were measured before and after the program. $X^2$-test and t-test were used to analyze the data. Results: After the obesity management program, the BMI and fat mass percentage in the experimental group were significantly reduced. The score for dietary attitudes and dietary habits changed in a positive direction. Conclusions: The findings from this study suggest that the obesity management program was effective in decreasing the rate of obesity and increasing the score for dietary attitudes and dietary habits. The program should be effective in the management of obesity in elementary school children.

• Preventive Nutrition and Food Science
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• v.7 no.1
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• pp.22-27
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• 2002

The cellulase from internal organs of edible snails was purified by fractionation with ammonium sulfate, DEAE-Sephadex chromatography and gel filtration on Sephacryl S-200 and Superose 12 HR 10/30. The specific activity of the purified cellulase was 85.1 units/mg protein with 24.3 purification fold from crude extract. Molecular weight of the enzyme was estimated to be approximately 74,000 dalton by gel filtration chromatography and SDS-PAGE eletrophoresis. T7e isoelectric point of the enzyme was determined to be pH 4.6. The optimum temperature and pH of the enzyme were 5$0^{\circ}C$ and pH 6.0, respectively. The enzyme was stable at 30~5$0^{\circ}C$ and pH 6.0~10.0. It was activates by Mn$^{2+}$, but inhibited by Li$^{2+}$, Zn$^{2+}$, Ag$^{2+}$ and Hg$^{2+}$./TEX> 2+/.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1763-1765
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• 2000

This paper presents deposition and characterizations of microcrystalline silicon ($\mu$ c-Si:H) films prepared by hot wire chemical vapor deposition at substrate temperature at 300$^{\circ}C$. The flow rates of $SiH_4$ gas are critical parameter for the formation of Si films with microcrystalline phase. We could obtain $\mu$ c-Si:H with columnar grain structure and volume fraction of 75% without H2 dilution. The electronic properties, hydrogen bonding configurations, and $H_2$ concentration inside the films are also strongly affected by $SiH_4$ flow rate, which is provided in this paper.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1984-1986
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• 2000

In pulsed-power techniques. Marx generator is generally used for the high-power device. but this generator has insulation and spatial problems. So we will suggest a pulse transformer that has a small size to generate the high voltage pulse instead of Marx generator. In this paper, Pulse duration is 4 [${\mu}s$] and the ratio of input and output voltage is 40[kV]/200[kV](step-up ratio=5). The output voltage and the process of pulse compression for pulse circuit are simulated by EMTP (Electro-Magnetic Transient Program). The secondary voltage of pulse transformer is about 200[kV] and pulse width is 4[t/s]. When the secondary winding of the pulse transformer is saturated. the pulse width is 1.25[${\mu}s$]. We selected dummy load 50[$\Omega$] for impedance matching. The pulse voltage of dummy load is 100[kV] and pulse width is 500[ns].

• Journal of the Korean Society of Costume
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• v.65 no.5
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• pp.88-102
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• 2015

The purpose of this study is to investigate the examples of using illustration as a strategic factor of composing brand cultures and as a factor for brand identity design. Through analyzing the external characteristics and the internal characteristics of illustration, this study will give suggestions on ways to apply the examples to real design. Illustration in external characteristics is investigated as a case of applying it directly to fashion design and to fashion marketing. Most of the fashion items were printed or weaved and most of the bags, shoes, and accessories were printed on the cover, attached as a patch, and expressed three-dimensionally. Illustration in internal characteristics is investigated as fixing and expansion of brand image, improving artistic and emotional value of brand, vitalization of masstige items, and cultural support and expression of social responsibility. The three themes used to develop the illustrations of "Hello ZIBI", which was used in this study, were "Graphic", "Forest" and "Flower", and these were based on modified brand symbol. Casual brands grafted fashion item designs onto T-shirts, bags, hats, and scarves. Marketing items were designed as shopping bags that could reflect brand image, as well as other items, such as key holders, mug cups, and tumblers, with designs that targeted specific age groups.

• Journal of the Korean Society of Costume
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• v.61 no.10
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• pp.1-15
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• 2011

Constructivism is an avant-garde movement that began in 20th-century Russia, which rapidly turned into an industrial society. This was one of the most experimental art movements, that wanted to be at the center of social and political-ideological change as it pursued a unique style, which portrayed the true essence of art and humanity. Russian constructivism greatly influenced modern fashion and suggested a new artistic standard. First, the artistic elements of Russian constructivism include photo montages, geometrical structures, color abstraction, and an asymmetrical order, through which the ideals of the Russian Revolution were substantiated, idealized, and materialized into an artistic form. Second, the different forms of Russian constructivism have various artistic characteristics such as popularity, spatiality, structuralism, decorativeness, and mobility, which were then expressed in modern fashion elaborated below. This study intends to reconstruct the meaning of Russian formalism and reflect it on fashion; thereby reconsidering the characteristics and the meaning of Russian constructivism in the context of today's fashion. This will broaden the meaning of constructivism and suggest a new direction for modern fashion.

• Journal of Ginseng Research
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• v.12 no.1
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• pp.68-75
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• 1988

Yields of ginseng seedlings and cultivation methods were investigated in 29 Ban-Yang-Jik (semimodified soil) nurseries to obtain some information about the production of ginseng seedling. The average number of available seedlings (useful for transplanting in the main field) per Kan ($180{\times}90$ cm) was 362. The percentage of available seedlings to the total seedlings harvested (rate of available seedlings) was 45 %. Although there were severe variations in the numbers and rates of available seedlings among the nurseries surveyed, the number of available seedlings were reduced due to both the short weighted and poor shaped (obese shape with poor root development) seedlings. The number of poor shaped seedlings was negatively correlated with height of seed-bed and frequencies of irrigation. Quadratic relations were noticed between rate of available seedling and heights of front post and rear post of shade. On the other hand, negative correlation was recognized between rate of available seedling and breadth of shade, but positive correlation was noted between rate of available seedling and frequencies of irrigation.