• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.5
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• pp.638-644
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• 2016

In this research, theoretical study on empirical analysis method to estimate waterdrop's deformation by shock wave is presented. Flow field is calculated using theoretical and empirical relations. Waterdrop's deformation including movement, size, mass, and orientation is modeled using empirical relations derived from existing experimental data. Developed method is applied to specific flight examples with arbitrary flight speed and vehicle's configuration. The flight speed is assumed to Mach number of 2 and 4. The diameter of waterdrop is varied from 1 to 5 mm. Waterdrops along the stagnation line in front of hemispherical nose with the radius of 50 mm and around a cone-shaped side wall with the half angle of 20 degree are considered. It is found that the maximum diameter of the waterdrop is increased up to 2.77 times the initial diameter. The mass is conserved more than 66.7 %. In the case of a cone-shaped side wall, waterdrop's orientation angles defined from the flight direction when the Mach number is 2 and 4 are calculated as 33.0 and 25.6 degree, respectively.

• Journal of Bio-Environment Control
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• v.12 no.4
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• pp.195-199
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• 2003

In polyethylene film house treated with surfactants(SF316+FB0800), waterdrops attached on film surface were absorbed to filter paper of 9 cm in diameter and measured 1.21 mL in control, 0.15 mL in 1% and 0.07 mL in 2% on December 10 at 10:00, 2002. However, there was no clear difference between surfactant concentrations 1% and 2%, And the most waterdrop was measured at 10:00 in daytime. As the air temperature was higher in greenhouse, waterdrop was sweled. So, the least waterdrop was measured at 14:00. In greenhouse covered with surfactants concentrated 1% and 2%, transmittances of solar radiation were 9.3% and 12.9% higher than control, respectively. In air temperature and relative humidity, there were no significant difference in all greenhouse. in forenoon, the air temperature and relative surfactant treated film greenhouse tended 1~2$^{\circ}C$ warmer than that of control. However, sil temperatures of surfactant treated film greenhouse tended 3~4$^{\circ}C$ warmer than that of control. During winter, the lettuce growth in surfactant treated film greenhouse was faster than that of control. However, there was no difference between surfactant concentrations of 1% and 2%.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.5 s.164
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• pp.742-752
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• 2007

The purpose of this study is the image of clothing according to the change of the dots' size was analyzed and its influence on the formation of the image of polka dots clothing was investigated. White waterdrop patterns were designed on the 12 kinds of black texture using Photoshop and CAD program in regular arrangement of diamond figure, composed of white waterdrop(0.5cm, 1.0cm, 1.5cm and 2cm in diameter) and interval(diameter : interval-1 : 1, 1 : 2, 1 : 4). Applying above specification, the photograph stimulus of 12 kinds of X-line one-piece dress with wide square neckline and without sleeve or detailed ornament was presented on a screen in the same size as when putting it on. The image of polka dots clothes was investigated by questionnaire survey. The object of the study was 320 females aged between 16 and 29. Factor analysis, one-way ANOVA, $Scheff\acute{e}$ verification and two-way ANOVA using SPSS 10.0 were carried out for data analysis. Followings are the results: 1) The image of polka dots clothing consists of 4 factors as aesthetics, brevity, dynamism and lightweight. 2) The size of the dot has a great influence on the formation of the image of polka dots clothing. 3) The evaluations of the image of polka dots clothing were different depending on the age and physical image, the personal characteristics of the object of investigation.

• Fashion & Textile Research Journal
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• v.9 no.3
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• pp.278-285
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• 2007

The purpose of this study is the image of clothing according to the change of the dots' interval was analyzed and its influence on the formation of the image of polka dots clothing was investigated. White waterdrop patterns were designed on the 12 kinds of black texture using Photoshop and CAD program in regular arrangement of diamond figure, composed of white waterdrop(0.5 cm, 1.0 cm, 1.5 cm and 2 cm in diameter) and interval(diameter : interval - 1 : 1, 1 : 2, 1 : 4). Applying above specification, the photograph stimulus of 12 kinds of X-line one-piece dress with wide square neckline and without sleeve or detailed ornament was presented on a screen in the same size as when putting it on. The image of polka dots clothes was investigated by questionnaire survey. The object of the study was 320 females aged between 16 and 29. Factor analysis, one-way ANOVA, Scheff$\acute{e}$ verication and two-way ANOVA using SPSS 10.0 were carried out for data analysis. The research finding are as follows. First, the image of polka dots clothing consists of 4 factors as aesthetics, brevity, dynamism and lightweight. Secondly, the interval of the dot has a great influence on the formation of the image of polka dots clothing. Lastly, the evaluations of the image of polka dots clothing were different depending on the age and physical image, the personal characteristics of the object of investigation.

• Applied Chemistry for Engineering
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• v.21 no.3
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• pp.301-305
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• 2010

In this study, the alkaline degreasing agent was developed for electroplating pretreatment process, and the efficiency and the durability was predicted. The alkaline deeping degreasing agent was prepared by blending sodium hydroxide (NaOH), sodium carbonate ($Na_2CO_3$), sodium silicate ($Na_2SiO_3$), and sodium lauric sulfate (SLS). The performance tests of the degreasing agent were evaluated in the $40{\sim}50^{\circ}C$ of the degreasing temperature and 30~40 min of the degreasing time. The efficiency and durability of the prepared degreasing agent were tested by the waterdrop formation test and Hull-cell plating test. The optimum ratio of alkaline degreasing agent was NaOH (30 g/L) + SLS (6.0 g/L) + $Na_2SiO_3$ (2.0 g/L) + $Na_2CO_3$ (40 g/L). Also, the optimum degreasing conditions were $50^{\circ}C$ of the degreasing temperature and 35 min of the degreasing time.

• Convergence Security Journal
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• v.8 no.4
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• pp.127-134
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• 2008

In this paper, we try to improve the accuracy of automatic measurement for analysis equipment by detecting efficiently the edge of a waterdrop with transparency. In order to detect the edge of a waterdrop with transparency, we use an edge detecting technique, MADD (Modified Adaptive Directional Derivative), which can identify the ramp edges with various widths as the perfectly sharp edges and respond effectively regardless of enlarging or reducing the image. The proposed edge detecting technique by means of perfect sharpening of ramp edges employs the modified adaptive directional derivatives instead of the usual local differential operators in order to detect the edges of image. The modified adaptive directional derivatives are defined by introducing the perfect sharpening map into the adaptive directional derivatives. Finally we apply the proposed method to contact angle arithmetic and show the effiency and validity of the proposed method.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2003.04a
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• pp.92-97
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• 2003

비닐하우스에서 피복자재로 폴리에틸렌(polyethylene), 초산비닐(ethylene vinyl-acetate) 및 염화비닐(polyvinylchloride)와 같은 연질필름을 90% 이상 사용하고 있으나 필름 표면에 물방울이 맺히는 것을 방지하는 무적성과 각종 먼지 등이 부착하는 것을 억제하는 방진성의 저하로 시설내 투광률이 5-l5% 떨어지고 다습하여 딸기와 같은 작물에 해로운 잿빛곰팡이병 발생이 심하여 생산성이 크게 떨어지고 있다('92, '97 원예연구소, '91 Jaffrin). (중략)

• Journal of the Korean Society of Costume
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• v.54 no.4
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• pp.113-127
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• 2004

This study examined the trend of pattern which appeared throughout men's clothing fashion magazine from 1999 to 2002 and the influence which the demographic characteristic have on the sensibility dimension of pattern and the preference degree of kinds of pattern. The results of study were as follows. 1) The pattern which was used most frequently on recent men's clothing was a length stripe, and the representation technique which was used most frequently on recent men's clothing was the technique of a geometric expression. 2) The pattern which men and women preferred most out of ten kinds of patterns-length stripe, width stripe, oblique stripe, check, square, waterdrop, paisley, flower of style shape, flower of realistic shape, flower of shape-was a length stripe. 3) The sensibility dimension of pattern image was composed of fascination, dignity, daring, gentleness, and reality. 4) Because sensitivity dimension and kinds of pattern were significant according to the distinction of sex, vocation, academic career, income, this study can conclude the demographic characteristic have an influence on sensitivity dimension and kinds of pattern.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1586-1588
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• 1994

Some interesting corona characteristics of a airgap of penpoint-to-plate with a tracing insulator paper has been investigated in a temperature and humidity controlled metal chamber. It is found that the positive and the negative carriers in the plasma region could be understood from the waterdrop traces on the paper, which indicate the bombardment by the one of electron or positive gas particle from the plasma region of near the point. It is also found that a corona discharge could be used as a means of a humidifying, since the discharge makes dispersion of watersprays from the penpoint. And the negative corona was more effective for waterspray dispersion than the positive ones.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2003.10a
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• pp.196-199
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• 2003