• Structural Engineering and Mechanics
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• v.60 no.5
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• pp.829-849
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• 2016

In this paper, experimental as well as numerical analysis of Glass Fiber Reinforced Polymer (GFRP) laminated composite has been presented under ballistic impact with varying projectile nose shapes (conical, ogival and spherical) and incidence velocities. The experimental impact tests on GFRP composite plate reinforced with woven glass fiber ($0^{\circ}/90^{\circ}$)s are performed by using pneumatic gun. A three dimensional finite element model is developed in AUTODYN hydro code to validate the experimental results and to study the ballistic perforation characteristic of the target with different parametric variations. The influence of projectile nose shapes, plate thickness and incidence velocity on the variation of residual velocity, ballistic limit, contact force-time histories, energy absorption, damage pattern and damage area in the composite target have been studied. The material characterization of GFRP composite is carried out as required for the progressive damage analysis of composite. The numerical results from the present FE model in terms of residual velocity, absorbed energy, damage pattern and damage area are having close agreement with the results from the experimental impact tests.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.12
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• pp.969-976
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• 2014

Nowadays, it is required for naval ships to estimate 3D underwater radiated noise pattern in all direction at peak frequencies of hull vibration for the reduction of being detected and doing the effective operation. For this purpose, the numerical method has to be developed to calculate 3D underwater radiated noise pattern with experimental data. It is very difficult to obtain the experimental data for the real ship. Alternative to get the experimental results is to use NAH(near-field acoustic holography) in acoustic tank with experimental model. Application of NAH in acoustic tank for the experimental model needs some investigation of reflection wave from the wall of the acoustic tank and unmeasured zone of the experimental model due to the supporting structure for it. In this study, the effect of reflection wave in the acoustic tank and unmeasured area of the experimental model when using the NAH was investigated with experiment and numerical model. From these, it is known for the error due to reflection wave can be reduced when the distance between the measurement plane and source is being shorten. Also, unmeasured area of the experimental model gives rise to some error in the estimation of the far-field acoustic pressure.

• Journal of muscle and joint health
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• v.17 no.2
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• pp.151-161
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• 2010

Purpose: The purpose of this study was to identify the effect of Tai Chi exercise on loneliness, sleep pattern, and instrumental activities of daily living in elderly women. Methods: A quasi-experimental design, a nonequivalent control group pretest-posttest was used. Elderly women who agreed to participated in the study were assigned into an experimental group (n=20) or a control group (n=20). The experimental group participated in Tai Chi exercise program (Sun-style 12 forms) for 50 minutes per session, 2 times a week for 8 weeks. Tai Chi exercise program consisted of 10 minutes for warm-up, 35 minutes for main session, and 5 minutes for cooling down. Study outcomes were measured through study questionnaires. Data were analyzed using Chi-square test, t-test and Mann-Whitney test by SPSS WIN 14.0 program. Results: Compared with the control group, the experimental group showed significant improvement in loneliness (t=-2.733, p=.009), sleep pattern (t=2.552, p=.015), and instrumental activities of daily living (z=-2.171, p=.030). Conclusion: Tai Chi exercise program may be an effective nursing intervention for elderly women.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.9-11
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• 2005

We propose a new content-based image retrieval using a block color co-occurrence matrix (BCCM) and pattern correlogram. In the proposed method, the color feature vectors are extracted by using BCCM that represents the probability of the co-occurrence of two mean colors within blocks. Also the pattern feature vectors are extracted by using pattern correlogram which is combined with spatial correlation of pattern. In the proposed pattern correlogram method. after block-divided image is classified into 48 patterns with respect to the change of the RGB color of the image, joint probability between the same pattern from the surrounding blocks existing at the fixed distance and the center pattern is calculated. Experimental results show that the proposed method can outperform the conventional methods as regards the precision and the size of the feature vector dimension.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.31B no.4
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• pp.1-8
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• 1994

In this paper, we propose an efficient two-step pattern matching method which promises shape distortion-tolerant recognition of handwritten of handwritten Hangul syllables. In the first step, nonlinear shape normalization is carried out to compensate for global shape distortions in handwritten characters, then a preliminary classification based on simple pattern matching is performed. In the next step, nonlinear pattern matching which achieves best matching between input and reference pattern is carried out to compensate for local shape distortions, then detailed classification which determines the final result of classification is performed. As the performance of recognition systems based on pattern matching methods is greatly effected by the quality of reference patterns. we construct reference patterns by combining the proposed nonlinear pattern matching method with a well-known averaging techniques. Experimental results reveal that recognition performance is greatly improved by the proposed two-step pattern matching method and the reference pattern construction scheme.

• The Research Journal of the Costume Culture
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• v.16 no.5
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• pp.852-862
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• 2008

The purpose of this paper is to find how to do the width of skirt and the girth of the waist in the adequate pattern making for the obese women's skirt. Appearance test of the five experimental skirts was evaluated by the four experts in clothing construction. At the same time, 3D clothing air volume was observed for the five types of experimental skirt with different size specifications. The results from the appearance test were as follows; when the width of skirt pattern is set for(the shell girth/2), it was suggested w/4+1(front), w/4(back) for girth of the waist. On one hand, in case of (the shell girth of front)/2+(the shell girth of back)/2, it was suggested(the waist girth of front)/2 and(waist girth of back)/2 for obese women's skirt with the best appearance. As results, it was found that the width of skirt pattern for the obese women should be the greatest shell girth instead of hip girth. In the case of the hip girth, the amount of ease on hip was suggested 6cm. It was found that pattern with the wrinkle of ease was full of the gaps between body and skirt in 3D clothing air volume. In spreading out to 2D flat pattern from 3D scan data, when the width of skirt pattern was set for(the shell girth of front)/2+(the shell girth of back)/2, it was suggested(the waist girth of front/2)+(the waist girth of back/2) than the shell girth/2 in girth of the waist for the best appearance. And the conversion of 3D scan data into 2D flat pattern in curve shape of crosswise had to spread out of the plane in straight line. The obese women's clothing should be manufactured with systematical consideration of the diversity and scarcity of the obese women's body shape.

• Fashion & Textile Research Journal
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• v.2 no.4
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• pp.353-359
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• 2000

The purpose of this study was to develop the jacket pattern drafting method for Korean middle-aged women. The study was composed as follows : 1. Body measurement and statistical analysis : Two hundreds and forty four middle-aged women between the ages of forty five and fifty nine were measured on 52 items. 2. Development of new jacket pattern drafting method : Measurement items necessary to draft new jacket pattern were back waist length, bust girth, waist girth, hip girth, back interscye breadth, front interscye breadth, neck base girth, nipple length, nipple to nipple breadth, 1/2 posterior shoulder length and sleeve length. Basic jackets constructed from the experimental patterns were examined through the fitting test. 3. Evaluation of the new pattern drafting method : The sensory evaluations for appearance and comfort were applied to evaluate the new jacket pattern by comparing it with one of the conventional jacket patterns (Lee Hyung-Suk's). According to the result of sensory evaluation, the new jacket pattern was more positive.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.7
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• pp.69-75
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• 1994

A very fine pattern formation process using double exposure is investigated, which can overcome the resolution limit of optical wafer stepper. The very fine pattern can be obtained by moving the edge profile of large pattern by means of moving the stepper stage. The simulation results show that the light transmittance decrease bellow 9%, and the contrast increase to 16.6% for the 0.3$\mu$m photoresist pattern exposeed by the double exposure using i-line wafer stepper. And the experimental results show that fine photoresist pattern as short as 0.2$\mu$m can be obtained without a loss of photoresist thickness. Also, it proves that the depth of focus for 0.3$\mu$m pattern is longer than $1.5\mu$m. And, the very fine negative photoresist pattern was formmed by using the double exposure technique and the image reversal process.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.10a
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• pp.280-283
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• 2004

Micro-lens patterned micro-mold fabrication method for Light Guiding Plate(LGP), kernel part of LCD-BLU(Back Light Unit), was presented. Instead of erosion dot pattern for LGP optical design, micro-lens pattern, fabricated by LIGA-reflow process, was applied. Optical pattern design method was also developed not only for negative pattern LGP, but also positive pattern LGP. During injection molding process, experimental study was conducted to improve replication quality and brightness of ${\sim}50um$ micro-lens pattern mold. The effect of mold temperature for the replication quality of micro-lens array was studied.

• The Research Journal of the Costume Culture
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• v.17 no.4
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• pp.616-625
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• 2009

With suffering financial crisis in 1997, Korea's fashion market has grown in the direction that satisfies the reasonable price and diverse consumer's sensitivity and needs. The aim of this study is to examine whether the cutting portion in the waist line is surely necessary for designing the jacket pattern in men's wear, by closely examining the effects of the cutting portion in the waist line on the external appearance and functionality given designing the jacket pattern in men's wear for the standard body type in 20s. The results of the study are as follows. As a result of evaluating the external appearance, when having evaluated by dividing into 14 items such as the whole surface, the side, and the back side, the experimental clothing, which wasn't cut the waist line, obtained the highest mark in 13 items and, the significant difference was indicated in 10 items except 4 items. As a result of evaluating performance, the experimental clothing, which wasn't cut the waist line, obtained the highest mark in 13 items among 25 items in the total. Next, the cutting portion in the waist line obtained the highest mark in 10 items for the experimental clothing with opening in 1.0cm. The next was indicated to be in order of the experimental clothing with 1.5cm and the experimental clothing with 0.5cm. Given seeing the above result, the cutting portion in the waist line given designing the jacket pattern for the standard body type in 20s could be known that the experimental clothing with the most excellent mark in the evaluation of performance was all the experimental clothing with 0.0cm whose waist line wasn't cut.