• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.4 s.247
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• pp.473-480
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• 2006

This paper explains analytical and experimental studies to evaluate the natural frequency of a composite carbody of Korean tilting train. The composite carbody with length of 23m was manufactured as a sandwich structure composed of 40mm-thick aluminium honeycomb core and 5mm-thick woven fabric carbon/epoxy face. From the finite element analysis, the 1st bending and 1st twisting natural frequency of the composite carbody were 11.67Hz and 14.4Hz, respectively. In order to verify the analytical results, the natural frequency measuring tests were performed. The measured 1st bending and twisting natural frequencies of the composite carbody were 10.25Hz and 11.0Hz, respectively. Both of these results satisfied the design requirement.

• Fashion & Textile Research Journal
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• v.11 no.6
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• pp.942-946
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• 2009

The trends of patents related to natural dyeing were examined in order to guide the development of natural dyeing into a high value-added technology. Total 181 patents data provided from KISTI were analyzed and following results were drawn. Korea had the overwhelming number of patents related to natural dyeing over Japan or United States of America from 1970 to 2007. In case of domestic, the number of patent applications were heavily focused on the metropolitan area in 1990's, but started to increase in the Honam region and Youngnam region in the first half of the year 2000 which indicated that the researches and the developments of natural dyeing were very active. In the case of foreign countries, most of their patent applications comes from the corporation such as a company while the number of patents applications from individuals overwhelms that of corporation in South Korea. Also, more of individuals' patent applications were denied than corporations' patents applications. The vegetable dye, a type of dyestuff which is a research subject for patent application, had the most research done above all other dyestuff.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.1
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• pp.11-22
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• 2007

This aims to review natural products transformed by mimic intestinal metabolisms with microorganisms and hydrolytic enzymes, which exhibit enforced biological activity, higher extraction yield and identification of active components. In the process, transformation to the smaller active compounds with enzymes and microbes mimics the pharmacological action of natural products by intestinal bacteria. In order to establish conditions for the fermentation and enzyme reaction, it is required to choose several natural products for biotransformation and investigate the optimal conditions for the fermentation or the enzyme reaction such as composition, temperature, pH, inoculum, and cultivation time. It is expected an increase of the internal absorption of the active materials without regard to the intestinal microbes or its ability through biosynthesis of the active materials by the microbes and enzymes. And this techniques can be applied to biotransformation of natural products such as sesaminol, resveratrol, 1-deoxy nojirimycin, naringenin, quercetin, and baicalin and to the metabolism study using the animal model.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.3
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• pp.105-112
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• 2000

For the purpose of building up the construction prospects of highway in consideration of natural environment. The tree planting and flower seeding in highway road side using native species were offered to natural landscape and resting area landscaping for peoples, and these area were 194place. The tree planting and flower seeding activity is to improve driving circumstances, and to conserve living and natural environment along the highways. And, preparation of ecotone and biotope at the highway surroundings for natural ecosystem conservation is an important activity, and planting of natural plants is generally carried out near wildlife ecoroads in order to give the way for animals. The primary purpose of this tree planting and seeding is not only to reduce environmental pollution, but also to enhance the ecological surroundings of highway circumference. Ultimately, It is essential that the constructive method of highway think over such as ecological environment and road design, surveying and management, construction, highway maintenance etc.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.2
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• pp.186-193
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• 2011

The NDIF method(non-dimensional dynamic influence function method) for free vibration analysis of arbitrarily shaped plates with the simply supported edge is newly developed in the paper. In order to extract the system matrix that gives the natural frequencies and natural modes of the plate of interest, the difficulty of measuring higher differential terms involved in the simply supported boundary condition is successfully overcome. Finally, the excellence of the characteristics of convergence and accuracy of the proposed method is shown through two verification examples, which indicate that natural frequencies and natural modes obtained by the proposed method are very accurate and swiftly converged even though a small number of nodes are used compared with FEM.

• Journal of the Korean Solar Energy Society
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• v.32 no.1
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• pp.40-47
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• 2012

According to the advancement of computer and simulation method, it becomes possible to predict indoor climate precisely by using CFD simulation coupled with heat conduction, convection, and radiation. However, predicting the indoor climate is generally conducted by using a simplified CFD coupled simulation method since it takes quite long time to use a general CFD simulation method. In this study, a simplified CFD coupled simulation was conducted in order to find out the effect of natural ventilation by wind-driven in atrium. As a result of calculation, it was clarified that the natural ventilation driven by temperature difference was not enough to remove the accumulated heat of upper zone and the natural ventilation by wind-driven was needed. Finally, it is required to decide the window direction and size based on correct indoor climate prediction method for the effective use of natural ventilation by wind-driven.

• Proceedings of the Zoological Society Korea Conference
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• 1998.10b
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• pp.139.1-139
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• 1998

No Abstract, See Full Text

• Journal of the Korea Fashion and Costume Design Association
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• v.9 no.2
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• pp.139-154
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• 2007

Wellbeing means the new life style leading a rich and nice life in which body and spirit is combined organically, and influence of wellbeing culture extends throughout the society. The purpose of this study is to analyze the aesthetic characteristics of Korean wellbeing fashion. Fashion photographs from leading monthly fashion magazines from 2001 to 2005 were analyzed. The styles and materials and colors were examined from 1,151 wellbeing fashion designs that is based on wellbeing culture. The major conclusions of the study are as follows : 1. The styles of wellbeing fashion in Korea include sportive, ecology, ethnic, retro styles in order. 2. Wellbeing fashion in Korea increased double in 2005 compared to 2001. Not least, sportive style and ethnic style rapidly increased. 3. Materials of wellbeing fashion in Korea include cottons, wools, chemical fibers, silks, jutes, functional fibers in order. Particularly the use of cottons in 2005 increased three times compared to 2001. 4. Of wellbeing fashion colors, yellow in bright tone were present the most, followed by white, red, black, green, blue, grey in order. Natural colors, vivid colors, pastel tone colors were used.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.12
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• pp.1310-1317
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• 2012

This study examines the possibilities to improve natural dyestuff's (Pinux$^{TM}$) dyeability and colorfastness for C/R (Cotton/Rayon (40/60)) and W/T (Wool/Tencel (10/90)) knitted fabrics in cationizing and smectiting for pre-treatment, simultaneous-treatment and post-treatment process sequences; as well as various other treatment methods. The sample dyeability showed the strongest K/S value in the order of smectite (S) < cationization + smectite (C+S) < cationization (C); however, the K/S value showed a low level in the simultaneoustreatment method of smectite. Colorfastness to washing improved in the order of C < C+S < S, and after the smectite post-treatment process, C/R improved from Grade 1 to Grade 4 and W/T improved from Grade 1-2 to Grade 4. Colorfastness to perspiration generally improved in the same order as the colorfastness to washing and after the smectite post-treatment process C/R, W/T sample's acidic and alkaline colorfastness to perspiration improved greatly. As for the colorfastness to rubbing, the addition of smectite in the simultaneous-treatment and post-treatment processes resulted in improved wet-colorfastness; however, smectite showed less effect on the colorfastness to light compared to other colorfastness ratings.

• Journal of applied mathematics & informatics
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• v.39 no.3_4
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• pp.419-435
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• 2021

This paper deals with numerical treatment of singularly perturbed differential equations involving small delays. The highest order derivative in the equation is multiplied by a perturbation parameter 𝜀 taking arbitrary values in the interval (0, 1]. For small 𝜀, the problem involves a boundary layer of width O(𝜀), where the solution changes by a finite value, while its derivative grows unboundedly as 𝜀 tends to zero. The considered problem contains delay on the convection and reaction terms. The terms with the delays are approximated using Taylor series approximations resulting to asymptotically equivalent singularly perturbed BVPs. Inducing exponential fitting factor for the term containing the singular perturbation parameter and using central finite difference for the derivative terms, numerical scheme is developed. The stability and uniform convergence of difference schemes are studied. Using a priori estimates we show the convergence of the scheme in maximum norm. The scheme converges with second order of convergence for the case 𝜀 = O(N^-1) and for the case 𝜀 ≪ N^-1, the scheme converge uniformly with first order of convergence, where N is number of mesh intervals in the domain discretization. We compare the accuracy of the developed scheme with the results in the literature. It is found that the proposed scheme gives accurate result than the one in the literatures.