• International Journal of Railway
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• v.1 no.3
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• pp.113-116
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• 2008

The long-tenn exposure of polymeric composite materials to extreme-use environments, such as pressure, temperature, moisture, and load cycles, results in changes in the original properties of the material. In this study, the effect of combined environmental factors such as ultraviolet ray, high temperature and high moisture on mechanical and thermal analysis properties of glass fabric and phenolic composites are evaluated through a 2.5 KW accelerated environmental aging tester. The environmental factors such as temperature, moisture and ultraviolet ray applied of specimens. A xenon-arc lamp is utilized for ultraviolet light and exposure time of up to 3000 hours are applied. Several types of specimens - tensile, bending, and shear specimens that are warp direction and fill direction are used to investigate the effects of environmental factors on mechanical properties of the composites. Mechanical degradations for tensile, bending and shear properties are evaluated through a Universal Testing Machine (UTM). Also, storage shear modulus, loss shear modulus and tan a are measured as a function of exposure time through a Dynamic Mechanical Analyzer (DMA). From the experimental results, changes in material properties of glass fabric and phenolic composites are shown to be slightly degraded due to combined environmental effects.

• Journal of the Korea Fashion and Costume Design Association
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• v.9 no.3
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• pp.191-203
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• 2007

The purpose of this study was to present a making method of jeans pattern with high fitness after deriving the appropriate shrinkage rate by material and washing process. According to the result of the exterior evaluation of test jeans, all 6 jeans were rated high with scores close to 3.5. Following the evaluation of satisfaction of usage by physical movement, the highest ranking was in the order of walking with normal steps, back bending $90^{\circ}$, chair sitting, climbing stairs and squatting. The shrinkage rate by physical area showed the highest score in the order of pants length, waist circumference, thigh circumference, knee circumference, hem circumference, hips circumference. In addition, the shrinkage rate was higher in warp direction than weft direction after washing finishing. As for the result of addition and reduction of pattern measurements by parts of jeans, waist circumference was $3.1{\sim}5.1cm$, hips circumference was $-1.2{\sim}4.2cm$, thigh circumference was $-0.9{\sim}3.1cm$ and pants length was $3.4{\sim}6.1cm$. That is, this results showed a wide range of addition and reduction according to material and washing finishing.

• Journal of Korea Game Society
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• v.10 no.3
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• pp.103-111
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• 2010

In this paper, an procedural approach to photorealistic rendering of woven fabric material is proposed. Previously proposed procedural approaches to fabric rendering have the disadvantage that the rendering result is not sufficiently realistic. In order to enhance the realism, researchers employed example-based approaches. However, those methods have serious disadvantage that they require huge amount of storage for the various reflectance properties of diverse materials. The proposed method can express the reflectance on weft and warp yarns by alternating the anisotropic reflectance on yarns. In addition, we propose the proposed method procedurally models the bumpy yarn structure of woven fabric to obtain plausible rendering results. The proposed method can efficiently reproduce realistic virtual fabric without any reflectance data sets.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.8
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• pp.1785-1791
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• 2003

This paper presents the mosaic method that the video sequence with shift and rotation information after Mellin Transform. The results are used to compute the projection matrix for each image registration. So before registration, we process camera calibration in order to reduce the image warp by camera and then compute the global projection matrix for image registration for reducing errors from rut image to last image. This paper describes the mosaic method that compute duplication and movement information quickly and robust noise using projection matrix on Mellin Transform.

• The KIPS Transactions:PartB
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• v.12B no.4 s.100
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• pp.437-442
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• 2005

For the purpose of speaker normalization in speaker independent speech recognition systems, experiments are conducted on a method based on Gaussian mixture model(GMM). The method, which is an improvement of the previous study based on vector quantizer, consists of modeling the probability distribution of canonical feature vectors by a GMM with an appropriate number of clusters, and of estimating the warp factor of a test speaker by making use of the obtained probabilistic model. The purpose of this study is twofold: improving the existing ML based methods, and comparing the performance of what is called 'soft decision' method with that of the previous study based on vector quantizer. The effectiveness of the proposed method is investigated by recognition experiments on the TIMIT corpus. The experimental results showed that a little improvement could be obtained tv adjusting the number of clusters in GMM appropriately.

• Korean Institute of Interior Design Journal
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• v.25 no.3
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• pp.82-89
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• 2016

This study investigated the preservation status of wooden architectural heritages, designated as Chungcheongbuk-do designated heritage in Jecheon. The purpose of this paper is to find the damage cause and the preservation method of wooden architectural heritages. It was conducted using the research methods of the existing literature and field survey to compare a current status of wooden architectural heritages. The result are as followings. Firstly, it was found the problems of a break, a damage, etc. in the platform and the problems of a cracking, an exfoliation, a corrosion, a warp, etc. in the wall. And, it was found a cracking of the beam(梁) and a roof tile(瓦), a falling of Angto(仰土), a sagging roof, etc. in the roof. Secondly, the damage causes of wooden architectural heritages were mostly caused by the physical limitations of the materials. And, it was caused by a rainwater, a subsidence of ground settlement, a destruction of waterproof membrane, etc. Lastly, the repair methods are making a quicklime layer in the soil mound on a cracking and an exfoliation part, a resin treatment or strut operation on a corrosion part of column, etc.

• Journal of the Korean Wood Science and Technology
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• v.41 no.2
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• pp.141-148
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• 2013

The goal of this study was to find the optimum lamina size from red pine (Pinus densiflora) and Japanese cedar (Cryptomeria japonica) logs for the cross laminated timber (CLT) production. From visual inspection of the logs from two species, red pine log showed a larger knot and warp compared to the Japanese cedar. Different cross-sectional sizes of lamina ($110mm{\times}30mm$, $110mm{\times}40mm$, $110mm{\times}50mm$, $50mm{\times}30mm$, $30mm{\times}30mm$) from two species were analyzed for yield and grade. Regardless of the species, the optimized cross sectional size for maximizing the yield was $110mm{\times}30mm$. In grading for the different size laminas from Japanese cedar and red pine, a higher percentage of the first and second grade was found from the $110mm{\times}30mm$ lamina cut.

• Transactions of Materials Processing
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• v.14 no.6 s.78
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• pp.533-540
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• 2005

The hemming process, composed of flanging, pre-hemming and main hemming, is the last one of a series of forming processes conducted on the automotive panels, having greater influence on the outward appearance of cars rather than on their performance. The hem quality can be quantitatively defined by the hemming defects including turn-down/up, warp and roll-in/out. However, it is difficult to evaluate and predict the hem quality through an experimental measurement or a numerical calculation since the size of defects is very small. This study aims to precisely evaluate the hemming defects, especially turn-down and roll-in, through numerical and experimental approaches and to investigate the influence of process parameters on the hem quality, focused on how to simulate the same conditions as in the experiment by the finite element analysis (FEA). The FEA results on the turn-down and roll-in obtained from a model composed of the optimum-sized elements, including a spring element linked to the flanging pad, and given the double master contact condition between the inner and outer panels, had a good correlation with the experimental data. It is thought possible to make an early estimate of the hem quality in a practical automotive design by applying the methodology proposed in this study.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.05a
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• pp.101-105
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• 2005

Hemming process, composed of flanging, pre-hemming and main hemming, is the last one of a series of forming processes conducted on the automotive panels, having a great influence on the outward appearance of them. The hem quality can be quantitatively defined by the hemming defects including turn-down, warp and roll-in. However, it is difficult to evaluate and predict the hem quality through the experimental measurement or the numerical calculation since the size of defects is very small. This study is focused on how to simulate in the finite element analysis (FEA) the same conditions as in the experiment. The FEA result on turn-down, that was obtained from a finite element model including the spring element linked to the flanging pad, had a good correlation with the experimental data. It was found that the radius of curvature of the flange deeply affects the final hem quality and therefore high rigidity of forming tools and tight assembling tolerance are highly recommended. An over-stroke of the main hemming punch is also proposed to reduce the turn-down.

• Journal of Fashion Business
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• v.19 no.2
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• pp.23-35
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• 2015

In this study, the effect of shrink-resist treatment agent on the wool finishing, specifically anti-felting of wool product was studied. We aimed at providing preliminary data leading to the diversification of high-value added fashionable wool product. Two type of wool fabrics, dense and sheer, were employed. The fabric specimens were treated with solutions of shrink-resist treatment agent with wet pick-up rate 110%, 130%, and 150%, respectively, by using a padding mangle. The solution treated fabric specimens were then dried at room temperature first, at $90^{\circ}C$ for 15 minutes in a drying oven, and finally cured at $130^{\circ}C$ for 3 minutes. Cured wool fabric specimens were then subjected to a felting process. The physical and mechanical properties, including shrinkage rate along warp/filling direction, thickness at specified measurement pressure, drape stiffness, and air-permeability, were analyzed. After felting process, the shrinkage rates of wool fabric specimens, treated with shrink-resist treatment agent, were lower than those of control wool fabric specimens. The stiffness values of wool fabric specimens measured by using Flexometer were increased.