• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.4
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• pp.123-129
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• 2018

A rotational drawing die which can form a long tube with spiral grooves on the surface is presented. The main feature of the proposed die is a rotation insert that is embedded into the die container for the die to freely rotate with respect to the drawing centerline as the materials are drawn. We employed a three-dimensional finite element model to investigate the effects of the rotational die on the material filling of spiral grooves. The material used in the finite element analysis was stainless 304. We also performed a pilot drawing test to verify the usefulness of the proposed rotational drawing die. Results reveal that the material filling of spiral grooves by the proposed rotational drawing die was in good agreement for both the finite element analysis and the drawing test. We found that the underfill in a conventional drawing die was reduced in the proposed rotational drawing die.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.4
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• pp.62-67
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• 2008

In this research, we developed a pilot wire-drawing machine as well as wire end-pointing roller. Using these machines, we performed a pilot wire-drawing test at different coating material and lubricant when the reduction ratio is 10 %. To inversely compute the friction coefficient between the coating layer of wire and the surface of die for a specific lubricant, we carried out a series of three dimensional finite element analysis. Results show that the drawing force is varied with the coating material of wire at the same reduction ratio and lubricant. It is noted that the frictional coefficient in drawing is dependent on the coupled property of coating material and lubricant, indicating the best coating material for a given lubricant.

• Journal of Oriental Neuropsychiatry
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• v.12 no.2
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• pp.185-191
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• 2001

Objectives: This study aimed to evaluate the usefulness as a screening test of Clock Drawing Test(CDT) compared with the standard K-DRS in probably dementia. Methods: The subjects for this study consisted of 19 elderly persons who visited to the outpatient department of Oriental Neuropsychiatry of the Kyunghee Oriental hospital. They received the K-DRS and the Clock Drawing Test. Three observers evaluated them with circle, numbers, hands. Inter-rater reliability of scores from Clock Drawing Test was assessed and Pearson correlation coefficients were used to examined the relationships between scores from Clock Drawing Test and K-DRS. Results: Correlations between individual raters was highly significant (r= .957, .974, and .970, respectively: p<.001). There was stastically significant correlations between K-DRS and CDT scores (r= 0.849, p<.001). Conclusions: The CDT can be rated reliably by observers and correlations between CDT and K-DRS is significantly high. We confirmed the usefulness of CDT as simple, easily administered, low cost, and reliable general screening test for dementia.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.1
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• pp.235-246
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• 1997

This study was done as a pilot study to develop a color test measuring children's dental anxiety. The subjects of study were 511 preschool children aged from 3 to 6. Caries experience was examined. Children's drawings of the dentist were collected and analyzed by the method of human figure drawing test modified by Sonnenberg and Venham. Colors of high dental anxiety level were black, brown, purple, red, yellow, pink, green, orange, blue, gray, yellow ochre, and white in that order. Colors of high frequency of use were yellow ochre, green, blue, red, orange, pink, black & purple, yellow, brown, gray, and white in that order. As the age increased, white & gray, yellow ochre, and blue increased and black, purple, and pink decreased. Boys liked green and blue, and girls liked orange and yellow. Filled teeth rate was highest in yellow ochre group and very low in black group. Children who had an educational dental visit before the test used green color more than the rest of children.

• Korean Journal of Construction Engineering and Management
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• v.17 no.3
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• pp.98-107
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• 2016

An information system in a construction project has been typically used for drawing, document management, and administration process. And it has limitations to support real-time communication and collaboration among project stakeholders. The objective of this research is to improve communication, information share, and task management by developing a collaboration platform among project stakeholders supporting various communication methods and contents. The platform developed in this research, named as CCP, aims to support communication and collaboration related activities beyond the scope of legacy systems at construction sites. CCP was validated through pilot test and user survey, and it was found to be very helpful for sharing and distributing information, tracking and recording, and improving a user's work capability.