• Journal of Biosystems Engineering
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• v.23 no.4
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• pp.381-390
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• 1998

An algorithm to extract the 3-D geometric information of a static object was developed using a set of 2-D computer vision system and a laser structured lighting device. As a structured light pattern, multi-parallel lines were used in the study. The proposed algorithm was composed of three stages. The camera calibration, which determined a coordinate transformation between the image plane and the real 3-D world, was performed using known 6 pairs of points at the first stage. Then, utilizing the shifting phenomena of the projected laser beam on an object, the height of the object was computed at the second stage. Finally, using the height information of the 2-D image point, the corresponding 3-D information was computed using results of the camera calibration. For arbitrary geometric objects, the maximum error of the extracted 3-D feature using the proposed algorithm was less than 1~2mm. The results showed that the proposed algorithm was accurate for 3-D geometric feature detection of an object.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.10 s.181
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• pp.2451-2460
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• 2000

In order to minimize straightness error of deflected shaft, a geometric adaptive straightness controller system is studied. A multi-step straightening and a three-point bending process have been developed for the geometric adaptive straightness controller. Load-deflection relationship, on-line identification of variations of material properties, on-line springback prediction, and real-time hydraulic control methodology are studied for the three-point bending process. By deflection pattern analysis and fuzzy self-learning method in the multi-step straightening process, a straightening point and direction, desired permanent deflection and supporting condition are determined. An automatic straightening machine has been fabricated for rack bars by using the developed ideas. Validity of the proposed system is verified through experiments.

• Research in Mathematical Education
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• v.9 no.3 s.23
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• pp.275-284
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• 2005

Tessellations are the pattern of iterations of geometric symmetry and translation. We can find them in the works of Escher who is the famous Dutch artist, and the American Indean life. Also, we can find the beauty of tessellations in the Korean traditional house door, Buddist temple architecture, palace's fence, etc. In the article, the figures of patterns we present are bird, fish, cat, pig, elephant, penguin, child and horse riding man, including Escher's, which are constructed using the computer geometric program, GSP (Geometer's Sketchpad). We want to talk about girl's disposition toward mathematics related to the figures. If they are supported by this kind of interesting figures constructed by their own hands, students will have more interest in learning geometric figures.

• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.462-465
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• 2000

It is important to compress three dimensional (3D) data efficiently, since 3D data are too large to store or transmit in general. In this paper, we propose a lossless compression algorithm of the 3D mesh connectivity, based on the vertex degree. Most techniques for the 3D mesh compression treat the connectivity and the geometric separately, but our approach attempts to exploit the geometric information for compressing the connectivity information. We use the geometric angle constraint of the vertex fanout pattern to predict the vertex degree, so the proposed algorithm yields higher compression efficiency than the conventional algorithms.

• Journal for History of Mathematics
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• v.21 no.2
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• pp.71-80
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• 2008

From the ancient Korea, our ancestor had designed the unique pattern which is Dan-chung, in architectures such as palace and Buddhist temple. In Dan-chung pattern, there are many various kinds, that is geometric pattern, arabesque pattern, plant pattern, flower pattern, animal pattern, Buddhist pattern and living pattern. So, we can see the tessellations in the Dan-chung pattern, moreover we can find the beauty of tessellation in the Korean traditional architectures and crafts. In this paper, I'll show you Korean traditional tessellations via GSP 4.0. which means geomeric program Geometer's SkechPad.

• 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.

• Fashion & Textile Research Journal
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• v.19 no.2
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• pp.134-139
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• 2017

This study proposes 3D printed shoe designs with patterns made by reinterpreting traditional Korean muntin patterns as customized designs that are unique to individual consumers and different from existing products. In the fashion industry, shoes with diverse designs grafted with 3D printing technology have been introduced. Artistic 3D printed shoes showcase the unique designs of designers. Functional and practical 3D printed shoes that can be worn during daily activities and during exercise have been actively developed. Traditional Korean pattern designs are also being recreated into designs reflecting the aesthetic sense of modern times with our own identity. The uniqueness of the traditional muntin patterns in geometric shapes, such as intersections of lines, rectangles, and octagons, are expressed in shoe designs with modern aesthetic senses by utilizing the traditional patterns that conform well to the modern geometric beauty of forms. This study was intended to develop 3D shoe designs that reinterpreted the motif of muntin patterns from among traditional Korean geometric patterns with a modern aesthetic sense. The octagonal patterns that express the scenery of spring can be seen through the muntins in traditional Korean-style houses were designed on the heels of shoes. Utilizing the Rhino CAD program and ProJet 660 Pro 3D printer, shoes were designed and printed. The processes for making shoes using 3D printing technology proposed in this study are significant because they represent the creation of designs in a new area. The results of this study might help in the development of 3D printed fashion products.

• Fashion & Textile Research Journal
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• v.8 no.6
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• pp.627-633
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• 2006

This study examined the kinds, expression, techniques and arrangement of patterns for the traditional women's costume from 1995 to 2002 in North Korea. And the results were compared with South Korean. Conclusions are as follows : In the kinds of patterns the natural plant patterns were much more frequently used in North Korea. These tendency was same to South Korea. And the geometric patterns were more frequently used in South Korea. According to frequency in the expression of patterns, it was the realistic, geometric, stylized shape in North Korea. To the contrary it was the stylized, geometric, realistic shape in South Korea. In terms of decorative techniques, not only the traditional embroidery, gold leaf, multicolored stripes, but also modern collages, painting, beads, applique, flounce, ruffle were used in North Korea. Modern techniques were found comparatively a lot in North Korea, traditional techniques were found comparatively a lot in South Korea. In terms of arrangement of patterns, the modern arrangement was much more frequently used. And localized type of modern arrangement was found comparatively a lot in South and North Korea. Therefore traditional beauty was generally expressed by natural patterns, realistic shape and modern beauty was generally expressed by modern techniques and arrangement of patterns in North Korea.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.9
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• pp.830-838
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• 2005

The present study investigated the optimization of the absorption performance of the vertical absorber tube with falling film by considering heat and mass transfer simultaneously. Effects of film Reynolds number, geometric parameters by insert device (spring) and flow pattern on heat and mass transfer performances have been also investigated. Especially, effects of coolant flow rate and the flow pattern by geometric parameters has been observed for the total heat and mass transfer rates through both numerical and experimental studies. Based on both predicted values, the optimal coolant flow rate was predicted as 1.98 L/min. The maximum absorption rate of the spring inserted tube was increased by the maximum of $20.0\%$ than those for uniform film of bare tube. Average Sherwood numbers and Nusselt numbers were increased as Reynolds numbers increased under the dynamic and geometric conditions showing the maximum absorption performance.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.2
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• pp.194-201
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• 2004

In the present study, the improvement of absorption characteristics on combined heat and mass transfer process in a falling film of a vertical absorber by change of geometric parameters were studied experimentally and analytically. The energy and diffusion equations are solved simultaneously to give the temperature and concentration variations at the liquid solution-refrigerant vapor interface and at the wall. Absorption behaviors of heat and mass transfer were analyzed through falling film of the LiBr aqueous solution contacted by refrigerant vapor in the absorber. Effects of film Reynolds number, geometric parameters by insert device (spring) and flow pattern on heat and mass transfer performances have been also investigated. Especially, effects of the flow pattern by geometric parameters have been considered to observe the total heat and mass transfer rates through falling film along the absorber. As a numerical and experimental result, maximum absorption rate was shown at the wave-flow by insert device (spring). The error ranges between experiment and analysis were from 5.8 to 12％ at Re$_{f}$ > 100.0.