• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 추계학술대회 논문집
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• pp.267-270
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• 2009

In the present investigation, we are newly developing a new forming process which can fabricate micro patterns on large-area polymeric substrates for high speed mass production. The key idea of the new process is to pressurize multiple vacuum-packed substrate-mold stacks above the glass transition temperature ($T_g$) of the polymeric substrates. The new process is thought to be promising micro-pattern fabrication technique in three aspects; firstly, isostatic pressing ensures the uniform micro-pattern replicating condition regardless of the substrate area. Secondly, the control of forming condition such as temperature and pressure can realize well-defined process condition exploited in the conventional hot embossing research field. Thirdly, multiple substrates can be patterned at the same time. A prototype forming machine for the new process was developed with the design consideration realizing the present idea. With a developed machine, micro prismatic array patterns with 50 um in size were successfully made on the $380{\times}300{\times}6\;mm$ PMMA plate.

• 제어로봇시스템학회논문지
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• 제16권7호
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• pp.625-631
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• 2010

This paper proposes lane recognition algorithm using lane prominence technique to extract lane candidate. The lane prominence technique is combined with embossing effect, lane thickness check, and lane extraction using mask. The proposed lane recognition algorithm consists of preprocessing, lane candidate extraction and lane recognition. First, preprocessing is executed, which includes gray image acquisition, inverse perspective transform and gaussian blur. Second, lane candidate is extracted by using lane prominence technique. Finally, lane is recognized by using hough transform and least square method. To evaluate the proposed lane recognition algorithm, this algorithm was applied to the detection of lanes in the rainy and night day. The experiment results showed that the proposed algorithm can recognize lane in various environment. It means that the algorithm can be applied to lane recognition to drive unmanned vehicles.

• 복식문화연구
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• 제15권6호
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• pp.1053-1062
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• 2007

This study purposed to restructure representative traditional patterns formatively, manufacture actual cultural products with traditional dyeing technique using persimmon, and commercialize the results of the research. Traditionally in Korea, the dying of natural fiber such as cotton, flax and silk with persimmon was called Galmul dyeing, and clothes made through Galmul dyeing were called Galot. Galot was very useful because it is strong, does not pick up dirt easily, dries easily, and is cool in summer. In addition, cloth dyed with persimmon becomes stiff, so it does not need to be starched or ironed after washing. Moreover, it does not transmit heat under direct rays and is highly air-permeable, so it is cool and useful for standing the heat. In this study, we used traditional persimmon dyeing technique, printing traditional patterns fit for contemporary people's aesthetic sense not through dip-dying but through printing. When persimmon dyeing is used in expressing patterns, it produces not only visual effect but also embossing effect due to the characteristic of persimmon that makes printed patterns stiff, so we can obtain unique texture distinguished from other printing methods. We chose seven motive patterns, which were lotus pattern symbolizing eternal life, peony pattern symbolizing wealth and rank and prosperity, character Su(壽) pattern widely used as a symbol of health, bird and cloud pattern in the Goryeo Dynasty, Sahapyeoeuisohwa(四合如意小花) pattern printed on brocade in the Goryeo Dynasty, lattice pattern, cloth pattern on wall paintings from the Period of the Three Kingdoms. From each pattern chosen as a motive was extracted unit patterns and the original pattern was restored using Adobe Illustrator. Restored patterns were restructured to be applied to cultural products fit for contemporary formative sense. Fabrics used in dyeing were cotton, linen, ramie, silk, and polyester. Although the same persimmon dyeing was applied, we produced different feelings of patterns using various fabrics and in some cases gold and silver powder was added for the effect of gloss in addition to the embossing of patterns. Using printed fabrics we manufactured tea pads, place mats, cushions, wrapping cloth for gifts, wallet, lampshades.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.72-76
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• 2003

Even though embossing is an effective SDM(Structural Dynamics Modification) technique, it is difficult to implement the method in fields owing to its geometric complexity. In this research low flat-top emboss shape, rather than general shape, is considered and a systematic procedure is derived in describing the emboss implementation procedure utilizing the fact that the emboss shape can be fully expressed only if the boundary elements are appropriately given. Best position to maximize natural frequencies is found using the procedure and usefulness of the suggested technique is illustrated.

• 한국산학기술학회논문지
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• 제10권1호
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• pp.19-24
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• 2009

구조물 동특성 변경법이란 부가 구조물의 첨가나 삭제, 재료 물성치의 변경, 구조물의 형상변경 등을 이용해 구조물의 동특성을 향상시킬 수 있는 매우 효과적인 방법이다. 하지만 이러한 구조물 동특성 변경법 중 구조물의 형상 변경을 통해 그 구조물의 동특성을 향상시키는 방법은 지금까지는 주로 엔지니어의 경험이나 많은 시간을 요하는 시행착오법에 의존해 왔다. 따라서, 앞선 연구를 통해 이러한 구조물의 형상 변경을 통한 동특성변경법에 있어서 기존의 경험이나 시행착오법에 의존하는 방법이 아닌, 체계화된 방법론을 제안하게 되었으며 하드디스크 드라이브 (HDD)에 성공적으로 적용하였다. 제안된 그루브를 통한 표면형상변형 동특성변경법을 검증해 보기 위하여, 본 연구에서는 모든 요소가 엠보싱 되어 있는 극한의 경우로부터 최적화를 수행하고 앞선 연구에서 얻어진 최적화 결과와 비교함으로써 제안된 방법론의 효과를 검토해 볼 수 있었으며, 1차 고유진동수를 높이기 위한 최적화 결과 그루브의 형상은 앞선 연구결과와 같음을 알 수 있었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1249-1253
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• 2007

Experimental studies on the fabrication of sub-30 nm nanofibers using weakly two-photon induced photopolymerized region have been carried out. For the generation of nanofibers inside or outside microstructures, an over-polymerizing method involving a long exposure technique (LET) was proposed. Such nanofibers can find meaningful applications as bio-filters, mixers, and many other uses in diverse research field. A multitude of nanofibers with a notably high resolution (about 22 nm) in two-photon polymerization was achieved using the LET. Furthermore, it was demonstrated that the LET can be employed for the direct fabrication of various embossing patterns by controlling the exposure duration and the interval between voxels. Thin interconnecting networks are formed regularly in the boundary of the over-polymerized region, which allows for the creation of various pattern shapes. Overall of this work, some patterns including nanofibers are fabricated by the LET.

• 한국전기전자재료학회논문지
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• 제19권2호
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• pp.130-138
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• 2006

We have investigated pattern scaling down of silicon stamps through the oxidation technique, During oxidizing the silicon stamps, silicon dioxide that has 300 nm and 500 nm thickness was grown, and critical deformations were not observed in the patterns. There was positive effect to reduce size of patterns because vertical and horizontal patterns have different orientation. We achieved pattern reduction rate of $26\%$. In addition, the formation of polymer patterns had been investigated with varied temperature and pressure conditions to improve the filling characteristics of polymers during nanoimprint lithography when pattern sizes were few micrometers. In these varied conditions, polymers had been affected by free space compensation and elastic stress relaxation for filling the cavities. Based on the results, defect control which is an important issue in the nanoimprint lithography were facilitated.

• 대한기계학회논문집A
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• 제31권12호
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• pp.1144-1149
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• 2007

Experimental studies on the fabrication of sub-30 nm nanofibers using weakly two-photon induced photopolymerized region have been carried out. For the generation of nanofibers inside or outside microstructures, an over-polymerizing method involving a long exposure technique (LET) was proposed. Such nanofibers can find meaningful applications as bio-filters, mixers, and many other uses in diverse research field. A multitude of nanofibers with a notably high resolution (about 22 nm) in two-photon polymerization was achieved using the LET. Furthermore, it was demonstrated that the LET can be employed for the direct fabrication of various embossing patterns by controlling the exposure duration and the interval between yokels. Thin interconnecting networks are formed regularly in the boundary of the over-polymerized region, which allows for the creation of various pattern shapes. Overall of this work, some patterns including nanofibers are fabricated by the LET.

• 패션비즈니스
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• 제9권1호
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• pp.1-20
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• 2005

This study is purposed to provide new idea for developing high value added fashion goods by studying relief effects of fashion design. Based on prior researches, various ways to give relief effects were searched and then modern fashion design cases were looked for which were referred to fashion-related magazines and collection-related internet sites since the late 1990s. The ways for relief effects are weaving, industrial finishing, sewing technique. Weaving techniques are about fancy yarns, variation of weaving structure, pile weave. Industrial finishing techniques which can make relief effects are embossing, heat-setting, shearing, pliss, burn out, flocking. Sewing techniques are quilting, pleats, embroidery, slash, attachment in accordance with the way to produce relief effects. The forms of relief effects are tactile pattern that cannot be seen in the distance, subtle relief pattern which is more three-dimensional than tactile pattern, rhythmical relief pattern, sculptural pattern, and deep-volumed pattern. The present research can provide practical data for design by studying techniques of relief effects and collecting and arranging design cases that have been sporadically carried out. The study on relief and unique surface effects can be a way to effectively stimulate and express emotions of modern people with various taste and individuality.

• 대한기계학회논문집B
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• 제32권9호
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• pp.676-682
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• 2008

Numerical analysis was carried out to examine the heat transfer and pressure drop characteristics of plate heat exchangers for absorption application using Computational Fluid Dynamics(CFD) technique. A commercial CFD software package, FLUENT was used to predict the characteristics of heat transfer, pressure drop and flow distribution within plate heat exchangers. In this paper, a welded plate heat exchanger with the plate of chevron embossing type was numerically analyzed by controlling mass flow rate, solution concentration, and inlet temperatures. The working fluid is $H_2O$/LiBr solution with the LiBr concentration of 50-60% in mass. The numerical simulation shows reasonably good agreement with the experimental results. Also, the numerical results show that plate of the chevron shape gives better results than plate of the elliptical shape from the view points of heat transfer and pressure drop. These results provide a guideline to apply the welded PHE for the solution heat exchanger of absorption systems.