• Journal of the Korea Academia-Industrial cooperation Society
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• v.3 no.2
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• pp.136-140
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• 2002

The investment casting process is used frequently to manufacture precise and complex shape metal parts. The previous wax pattern manufacturing process takes long time and high costs because the process is performed by hands. In order to improve the wax manufacturing process, a new process is developed to manufacture the wax pattern by using a rapid prototyping system. A CastForm pattern is made by a Selective laser Sintering type RP with CastForm powder. The CastForm pattern is dipped in the melted wax liquid, and the melted wax penetrates into the pores of the CastForm pattern. Wax pattern is obtained after cooling the CastForm pattern slowly. A stainless steel part has been manufactured by the suggested process. By obtaining the suggested process the manufacturing time and costs are reduced largely and the accuracy is improved.

• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.1
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• pp.123-136
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• 2023

To develop smart sportswear capable of measuring biometric data, we created a close-fitting pattern using two- and three-dimensional (2D and 3D, respectively) methods. After 3D virtual fitting, the tightness of each pattern was evaluated using image processing of contact points, mesh deviation, and cross-sectional shapes. In contact-point analysis, the 3D pattern showed high rates of contact with the body (84.6% and 93.1% for shirts and pants, respectively). Compared with the 2D pattern, the 3D pattern demonstrated closer contact at the lower chest, upper arm, and thigh regions, where electrocardiography and electromyography were primarily carried out. The overall average gap was also lower in the 3D pattern (5.27 and 4.66 mm in shirts and pants, respectively). In the underbust, waist, thigh circumference, and mid-thigh circumference, the cross-section distance between clothing and body was showed a statistically significant difference and evenly distributed in the 3D pattern, exhibiting more closeness. The tightness and fit of the 3D smart sportswear sensor pattern were successfully evaluated. We believe that this study is critical, as it facilitates the comparison of different patterns through visualization and digitization through 3D virtual fitting.

• Journal of the Korea Society of Computer and Information
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• v.16 no.4
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• pp.1-13
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• 2011

In this paper, we propose a gesture recognition system to recognize motions using the shape information of MHI (Motion History Image). The system acquires MHI to provide information on motions from images with input and extracts the gradient images from such MHI for each X and Y coordinate. It extracts the shape information by applying the shape context to each gradient image and uses the extracted pattern information values as the feature values. It recognizes motions by learning and classifying the obtained feature values with a SVM (Support Vector Machine) classifier. The suggested system is able to recognize the motions for multiple people as well as to recognize the direction of movements by using the shape information of MHI. In addition, it shows a high ratio of recognition with a simple method to extract features.

• Journal of the Korea Fashion and Costume Design Association
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• v.13 no.2
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• pp.47-62
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• 2011

The purpose of this study was to investigate the knitwear preferences and purchase behaviors of university students. The subjects were 493 university students in Daejeon and Chungnam Provinces. The method of this study was a survey and measurement instruments were 34 stimuli which were manipulated pullover patterns and shapes and self-administrated questionnaire with knitwear design preference items and knitwear purchase behavior items. Data were analyzed by factor analysis, frequency analysis, Cronbach'${\alpha}$, t-test, ANOVA and $Sch{\acute{e}}ffe$ test using SPSS program. The results of the study were as follows. First, university students most preferred achromatic colors, pastel tones, solid patterns, and 100% cotton. Second, as for knitwear purchase behaviors, university students considered the esthetical factor to be most important among 4 dimensions (comfortable, esthetical, economical, and conspicuous factors) as important purchase criteria, and they used internet web sites for knitwear purchases. Third, there were significant differences in preferred pullover shape depending on neckline shape, neck depth, sleeve shape and clothing length. University students preferred the classic pullover design with V neckline, normal neck depth, set-in sleeves and normal length. Fourth, university students preferred the cloud motif and riding man motif among the 9 Baekje traditional motifs and one point small pattern on the left chest and crosswise bending pattern for pattern arrangement.

• Journal of Korea Multimedia Society
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• v.14 no.2
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• pp.269-281
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• 2011

For the MD-TIX(multidimensional type inheritance index) that supports query processing for the type inheritance concept in XML databases, this paper presents an index tuning algorithm that enhances the performance of the XML query processing according to the query pattern. The MD-TIX uses a multidimensional index structure to support complex XML queries involving both nested elements and type inheritance hierarchies. In this index tuning algorithm, we first determine a shape of index page regions by using the query information about the user's query pattern, and then construct an optimal MD-TIX by applying a region splitting strategy that makes the shape of the page regions into the predetermined one. The performance evaluation results indicate that the proposed tuning algorithm builds an optimal MD-TIX by a given query pattern, and in the case of the three-dimensional query regions for the nested predicates of path length 2, the performance is much enhanced according to the skewed degree of the query region's shape.

• Korean Journal of Optics and Photonics
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• v.15 no.1
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• pp.79-85
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• 2004

We report on a transmittance controlled photomask with phase patterns on the back quartz surface. Theoretical analysis for changes in illumination pupil shape with respect to the variation of size and density of backside phase patterns and experimental results for improvement of critical dimension uniformity on a wafer by using the transmittance controlled photomask are presented. As phase patterns for controlling transmittance of the photomask we used etched contact-hole type patterns with 180" rotative phase with respect to the unetched region. It is shown that pattern size on the backside of the photomask must be made as small as possible in order to keep the illumination pupil shape as close as possible to the original pupil shape and to achieve as large an illumination intensity drop as possible at a same pattern density. The distribution of illumination intensity drop suitable for correcting critical dimension error was realized by controlling pattern density of the contact-hole type phase patterns. We applied this transmittance controlled photomask to a critical layer of DRAM (Dynamic Random Access Memory) having a 140nm design rule and could achieve improvement of the critical dimension uniformity value from 24.0 nm to 10.7 nm in 3$\sigma$.TEX>.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1048-1052
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• 2008

Difficulties in developing process of Liquid Crystal Display(LCD) products such as frequent design modifications, various design requirements, and short-term development period bring on the need of integrated design approach that is efficient and easy to handle. Back Light Unit(BLU) of the LCD, which drastically affects the optical performance of LCD products, is divided into in-coupling part and out-coupling part. Serration of the in-coupling part flattens the light received from point light sources and dot pattern of the out-coupling part regularizes the light sent to screen. Therefore, the optical performance of a LCD product is largely influenced by the shape of serration and the arrangement of dot pattern. In this research, a new design approach which enables to improve the optical performance of LCD products and overcome the prementioned difficulties in developing process of LCD products is proposed. The shape of serration is parameterized to 3 parameters and out-coupling part is partitioned into 10 partitions to apply the optimization technique to this problem. 3 parameters for the shape of serration and densities of 10 partitions are used as design variables in the design optimization. Optical simulation tool named SPEOS is used to evaluate the optical performance of the LCD product. Since the optical simulation uses the random ray tracing technique, numerical noise may possibly be included in the simulation process. To solve the problem caused by numerical noise, the PQRSM which can stably find the solution of the noise problem is used in this research.

• Fashion & Textile Research Journal
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• v.23 no.5
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• pp.545-558
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• 2021

This research analyzed the Chinese style design embodied in the collections of the new generation of fashion designers shown during the Shanghai Fashion Week to improve the understanding of Chinese style and the modernization of Chinese design. The research questions were 1) studying the development of the Chinese fashion industry chronologically and investing young designers' current situation, 2) investigating young designers' awareness of Chinese style and analyzing Chinese style design in collections. A literature and case study were conducted as the research method. The literature study focused on the books about the Chinese fashion industry and history, newspaper, articles, and so on. The case study was conducted among 63 Chinese style collections in 2016-2020 SFW by investigating fashion magazine reviews, articles, and so on. The findings are as follows: 1) Young Chinese fashion designers' awareness of Chinese style has three characteristics; the nonmaterial tendency from decreasing stereotyped images, combination of traditional culture and local youth culture, and commercialization with trends. 2) Chinese elements, including natural, character, and cultural elements were predominantly used in the concept, pattern, and shape. Nonmaterial characteristics were identified in concept, cultural combination characteristics in concept, shape, color, material, and pattern, and trend commercialization in shape, color, and pattern. In conclusion, Chinese young fashion designers had strong national consciousness and new awareness of Chinese style fashion in decreasing the stereotyped images of China. Thus, they used more varied expressions. Meanwhile, they faced difficulties in expressing nonmaterial Chinese elements by balancing them with Chinese style and globalization.

• The Journal of the Acoustical Society of Korea
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• v.40 no.4
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• pp.347-358
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• 2021

The objective of this study is to optimize the shape of doubly curved surface where a conformal array is equipped. That surface is modeled with a double-ellipsoid solid controlled by four parameters. By analyzing the performance of the conformal array beams with the beam pattern synthesis, two design parameters are determined. Then, we define the weighted object function which is formulated as the sum of sharp indexes for directivity index, the elevation resolution, and the bearing resolution. The direct calculation on all grids is used to evaluate the weighted object function and seek the optimal value of two design parameters when the weightings are given. In the simulation, four kinds of weighting cases are respectively applied to evaluate the weighted object function. The optimal shapes of double-ellipsoid solid are shown in each case. Especially, when the uniform weightings are used, the double-ellipsoid solid with more smooth surface is obtained.

• Journal of Fashion Business
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• v.17 no.2
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• pp.63-81
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• 2013

A Study using compare and analyze about differences among three patterns(shape and size of pattern, fitting and amount of air gap and so on) through 3D simulation. This study use 3D simulation program, DC Suite version 3.0. The results are as a follows: The results of estimation about total appearance, the pattern of Bunka is best of all pattern about total fitting and silhouette of front and back side. The pattern of armstrong and on&on stand low in estimation. As the total fitting, the pattern of Bunka is 4.40, the pattern of Armstrong is 2.60 and the pattern of On&on is 1.60. The result show better pattern of Bunka than pattern of Armstrong and On&on. When we examine about space between body and cloth, the pattern of Bunka is best. The pattern of Armstrong don't have problems about back side but front side have some problem of getting loose. Because it only have a waist dart so dart size is too big. The pattern of On&on have so much space because it don't have a waist dart. On the amount of air gap, the pattern of Bunka squash up body so it have the amount of air gap 0.08 at bust circumference and underbust circumference. Next is the pattern of Armstrong, amount of air gap is 0.14 at bust circumference and 0.23 at underbust circumference. The pattern of On&on's amount of air gap is 0.30 at bust circumference and 0.37 at underbust circumference. So the pattern of Bunka is bodice block of the best closing adhesion and the On&on is a loose-fitting pattern.