• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1271-1272
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• 2006

The vacuum infiltration method is one of the composite producing methods. There are several parameters in composite production by vacuum infiltration. One of them is particle size of reinforcement in particulate reinforced composites. In this study, MgO powder and Al were used as reinforcement and matrix respectively. MgO powders with different size and amount to give same height were filled in quartz tubes and liquid metal was vacuum infiltrated into the MgO powder under same vacuum condition and for same time. Infiltration height was measured and microstructure and fracture behavior of composite were investigated. It has been found that infiltration height and fracture strength were increased with particulate reinforcement sizes. It has also been determined that molten metal temperature facilitates infiltration.

• Journal of Advanced Marine Engineering and Technology
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• v.26 no.6
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• pp.646-652
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• 2002

The influence of reciprocating frequency and radius on heat transfer in the roughened rectangular channel is experimentally investigated. The aspect ratio (width/height) of the duct is 2.33 and the rib height is one fifteenth of the duct height. And the ratio of rib-to-rib distance to rib height is 10. The discrete ribs were periodically attached to the button wall of the duct with a parallel orientation. The parametric test matrix involves Reynolds number, reciprocating, and reciprocating radius, in the ranges, 1,000∼6,000, 1.7∼2.5 HB and 7∼15cm, respectively. The combined effects of reciprocating frequency and reciprocating radius have considerable influence on the heat transfer due to the modified vortex flow structure.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.244-249
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• 2008

In this study, the characteristics of flow in outdoor unit were numerically analyzed. Parametric studies were performed to compare the effect of bell mouth height, fan height and fan width concerned with flow rate. The result indicated that the flow rate was dependent on the bell mouth height, while it was negligibly affected by the fan height and fan width. The fan width was found to affect the velocity distribution at heat exchanger face.

• Journal of the Semiconductor & Display Technology
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• v.10 no.2
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• pp.97-102
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• 2011

Lots of 2D vision algorithms have been applied for inspection. However, these 2D vision algorithms have limitation in inspection applications which require 3D information data such as the height of semiconductor chips. Stereo vision is a well known method to measure the distance from the camera to the object to be measured. But it is difficult to apply for inspection directly because of its measurement error. In this paper, we propose two adjustment methods to reduce the error of the measured height data for stereo vision. The weight value based model is used to minimize the mean squared error. The average value based model is used with simple concept to reduce the measured error. The effect of these algorithms has been proved through the experiments which measure the height of semiconductor chips.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.16 no.1
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• pp.18-29
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• 1990

In this report, the variation of skin surface between before treatment and after treatment was investigated by skin image analyzer. The 30 volunteers were applied cream and lotion on the forearm Inside for 4 weeks, and the measurement parameter of skirl surface was adopted peak, length, height, and width. The results were as follows ; 1. variation trends of parameters was showed that number of peaks were increased, but length, height and width were decreased. 2. The order of improvement for skin surface are as follow ; height > length > peak > width. 3. And also disclosed that the number of peak has a correlation with width, and length has a correlation with height.

• Journal of the Korean Wood Science and Technology
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• v.50 no.2
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• pp.126-133
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• 2022

In this study, I used wood pellets as an eco-friendly sound-absorbing material. The aim of the research was to analyze the effect of the filling height of wood pellets on sound absorption. This was done using two types of wood pellets of different lengths (A group: 1.5-3 cm, B group: less than 1.5 cm). With increasing filling height of the wood pellets, the optimum sound absorption shifted towards a lower frequency. The group B wood pellets had better sound absorption capacity than the group A ones. The optimum sound absorption coefficient of group A filled to a height of 7 cm was 0.722 at 864 Hz. On the other hand, that of group B filled to a height of 7 cm was 0.764 at 862 Hz, 5.82% higher than that of group A. While wood pellets are used as an eco-friendly fuel, the results of this study suggest the possibility of using wood pellets as an eco-friendly sound-absorbing material.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.4
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• pp.298-304
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• 2014

The lifting-line method based on Weissinger's method is extended to be able to analyze the ground effect. The method is applied to predict the variation of aerodynamic performance due to ground effect for the elliptic wing with aspect ratio of 10 and the wing of human powered aircraft. While the vortex strength of the wing increases slightly, the downwash decreases significantly as the wing approaches to the ground. For the wing of human powered aircraft, the increment of lift at the height of 2m is 5% than the lift outside the influence of ground effect. The decrease of induced drag at the height of wing span is 10% and at the height of 2m is 55% than that out of ground effect.

• Earthquakes and Structures
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• v.18 no.4
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• pp.467-480
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• 2020

Concrete rectangular liquid storage tanks are widely used, but there are many cases of damage in previous earthquakes. Nonlinear fluid-structure interaction (FSI) is considered, Mooney-Rivlin material is used for rubber bearing, nonlinear contact is used for sliding bearing, numerical calculation models of no-isolation, rubber isolation, sliding isolation and hybrid isolation concrete rectangular liquid storage tanks are established; dynamic responses of different structures are compared to verify the effectiveness of isolation methods; and influences of earthquake amplitude, bidirectional earthquake and far-field long-period earthquake on dynamic responses are investigated. Results show that for liquid sloshing wave height, rubber isolation cause amplification effect, while sliding isolation and hybrid isolation have reduction effect; displacement of rubber isolation structure is much larger than that of sliding isolation with limiting-devices and hybrid isolation structure; when PGA is larger, wall cracking probability of no-isolation structure becomes larger, and probability of liquid sloshing wave height and structure displacement of rubber isolation structure exceeds the limit is also larger; under bidirectional earthquake, occurrence probabilities that liquid sloshing wave height and structure displacement of rubber isolation structure exceed the limit will be increased; besides, far-field long-period earthquake mainly influences structure displacement and liquid sloshing wave height. On the whole, control effect of sliding isolation is the best, followed by hybrid isolation, and rubber isolation is the worst.

• Journal of the Korean Society of Clothing and Textiles
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• v.15 no.3 s.39
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• pp.297-307
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• 1991

The purpose of this study was to investigate the effect of physical type and age on preference for color and fabric motifs in women's clothing design. Color preference measures consisted of fabric samples in solid colors and drawings of clothing styles painted in colors. Preference for fabric motifs was assessed by printed fabrics in various patterns and sizes. All of the preference measures were devised specifically for this study. Furthermore, items on height and weight for physical type as well as age of the subjects were included in the questionnaire. Data were obtained by means of structured interviews and self-administered questionnaires from 588 women ($20\~60$ years of age) in seoul. Analysis was by chi-square ($X^{2}$), frequency, percentage, and mean. On color preference, a small but significant body type, height, and age effect was found on some types of clothing. Preference for fabric motifs was affected by body type; height of subjects was related to preference for size of motifs, and age was related to choice, size, and width of striped motifs. It was concluded that body type, height, and age are 1e3st effective in predicting color preference. Fabric motif preference was influenced more by age than by body type or height. Generally, there was some similarities in preference for lines and fabric patterns among slim body types, tall figures, and younger age groups as well as heavy body types, short figures, and older age groups.

• Journal of the Korean Society of Physical Medicine
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• v.2 no.1
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• pp.49-59
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• 2007

Objective : To purpose of this study was the most of the ladies wear high-heeled shoes at lease 4 to 5 day a week but the effect of it's height on the lumbo-sacral legion angle has not been clearly defined. Method : Subject were 20 young ladies, who had majored in physical therapy of the Dae-gu Health College. Method 1. PACS system X-ray was used to measure the lumbo-sacral legion angle under the condition of bare foot, 3cm, 7cm high-heeled at standing position. 2. Spinal Mouse was used to measure the spinal segment motion angle and length under the condition of bare foot, 3cm, 7cm high-heeled at being Flexion-Extension position Result : The result of this study were as follow I. Significant statistical increase in lumbar lordosis was observed as the heel height was increased from bare foot to 7cm high-heeled(p<.05), but there was no significant difference in the lumbo-sacral angle & sacral angle(p>.05). 2. The Height and the weight of the subjects, their preference on the shoes didn't affect the lumbo-sacral lesion angle(p>.05) 3. The variation of the heel height didn't affect the spinal segment motion angle and length(p>.05). Conclusion : There is strong relationship between the high of heel with increasing the lumbar lordosis(p<.05).