• Journal of applied mathematics & informatics
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• v.6 no.1
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• pp.111-126
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• 1999

The article is devoted to mathematical modeling of prob-lems of stochastic optimization of the plastic metal working. Classifi-cation and mathematical statements of such problems are proposed. Several calculation techniques of the single goal function are pre-sented. The probability theory and the Fuzzy numbers were applied for solution of the problems of stochastic optimization.

• Journal of Radiation Protection and Research
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• v.33 no.4
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• pp.173-181
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• 2008

To ensure the performance of radon detectors, three passive radon detectors ($RadTrak^{(R)}$, $Radopot^{(R)}$, and $E-PERM^{(R)}$)have been reviewed. The difference ratios of RadTrak and Radopot tested in the radon standard chamber were -13.2% and -6.0%, respectively, which were in good accordance within 20% of the value measured by $AlphaGUARD^{(R)}$. To ensure the performance of the long term measurement, the 3 detectors were installed at the same position of approximately one hundred of dwellings for one year. The correlation curve between RadTrak and Radopot shows good agreement with a correlation coefficient ($R^2$) of 0.91. However, The correlation curve between E-PERM and Radopot shows bad agreement ($R^2$ = 0.021). In addition, the distribution map of annual mean indoor gamma dose rate measured with E-PERM was not in accordance with the distribution map of outdoor gamma dose rate measured by Portable Ion Chamber. According to the results, some requisites for the selection of the radon passive detectors in the large-scale indoor radon survey were discussed.

• Textile Coloration and Finishing
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• v.26 no.4
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• pp.353-362
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• 2014

This study attempted to determine the effects of fermented green tea extracts on hair by using them in a perm. For this, hair is bleached, and then the fermented green tea extracts and water were supplied to the hair using a mist sprayer. Then the hair was permed, and hair damage was tested. Regarding hair moisture levels and wave formation, specifically, the morphological changes of hair were investigated with the Scanning Electron Microscope(SEM). The study results found the following. In terms of wave formation, the fermented green tea extract-based perm was much better than the general perm. In addition, hair bleaching was more serious in the latter. According to analysis on hair moisture using SEM, hair damage was more prevalent in the general perm as well. Therefore, it was confirmed that green tea extract-based perms cause less damage to the cuticle. In other words, the potential of fermented green tea extracts as a hair cosmetics material was discovered. Furthermore, it appears that the study results contribute to the development of low-irritating scalp and hair care products using the anti-inflammatory and antimicrobial properties of the fermented green tea extracts.

• Journal of the Korea Computer Graphics Society
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• v.11 no.1
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• pp.40-49
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• 2005

Several optimization techniques have been proposed for volume ray casting, but these cannot achieve real-time frame rates. In addition, it is difficult to apply them to some applications that require perspective projection. Recently, hardware-based methods using 3D texture mapping are being used for real-time volume rendering. Although rendering speed approaches real time, the larger volumes require more swapping of volume bricks for the limited texture memory. Also, image quality deteriorates compared with that of conventional volume ray casting. In this paper, we propose a data structure for real-time volume ray casting named PERM (Precomputed dEnsity and gRadient Map). The PERM stores interpolated density and gradient vector for quantized cells. Since the information requiring time-consuming computations is stored in the PERM, our method can ensure interactive frame rates on a consumer PC platform. Our method normally produces high-quality images because it is based on conventional volume ray casting.

• The Korean Journal of Community Living Science
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• v.21 no.1
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• pp.117-124
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• 2010

Recently, research on variables associated with hair styles are increasing with the spreading of total coordinated intention in the fields of clothing and cosmetology. In the present study, we focused on examining the skin temperature on the scalp(the vertex, temporal, and occiput), humidity on the occiput, skin temperatures (the forehead, back of ear, back of neck, upper back, abdomen, forearm, hand, thigh, calf, and foot), rectal temperature, total body mass loss by hair styles in a thermal neutral environment. Four young females participated as subjects. For a certain period, each subject had the five different hair styles in a random order: (1)Straight short hair(SS), (2)Perm waved short hair(PS), (3) Straight long hair(SL), (4)Perm waved long hair(PL), (5)Ponytail style(PT). Subjects wore briefs, bra, shirts with long sleeves, long legged training pants, and socks. The environmental variables of a climatic chamber were kept constant at $21{\pm}0.5^{\circ}C$ of air temperature and 55${\pm}$5%RH of air humidity. The results indicated the following: The skin temperature and humidity on the scalp did not show any significant differences among five different hair styles, but straight long hair style(SL)was the highest on the vertex, temporal, and occiput. The temporal skin temperature($29.8\sim30.8^{\circ}C$) was the highest, while the vertex skin temperature($28.7\sim30.1^{\circ}C$) was the lowest. Humidity on the occiput was the highest in the perm waved long hair style(PL). The back of ear skin temperature was significantly lower in the ponytail style(PT) than in the other four hair styles(p<.001). In the straight long hair style(SL), the skin temperature on the back of the neck and on the upper back were significantly higher than those of the other four hair styles(p<.01). Mean skin temperature and rectal temperature had no significant differences among hair styles. Total body mass was the highest in the perm waved long hair style(PL)(p<.05). We acquired fundamental data to enable the improvement of the current hair clinic system, wigs, functional hats, and helmets.

• Journal of the Korean institute of surface engineering
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• v.49 no.3
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• pp.286-300
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• 2016

Pd-Ag alloy membranes have attracted a great deal of attention for their use in hydrogen purification and separation due to their high theoretical permeability, infinite selectivity and chemical compatibility with hydro-carbon containing gas streams. For commercial application, Pd-based membranes for hydrogen purification and separation need not only a high perm-selectivity but also a stable long-term durability. However, it has been difficult to fabricate thin, dense Pd-Ag alloy membranes on a porous stainless steel metal support with surface pores free and a stable diffusion barrier for preventing metallic diffusion from the porous stainless steel support. In this study, thin Pd-Ag alloy membranes were prepared by advanced Pd/Ag/Pd/Ag/Pd multi-layer sputter deposition on the modified porous stainless steel support using rough polishing/$ZrO_2$ powder filling and micro-polishing surface treatment, and following Ag up-filling heat treatment. Because the modified Pd-Ag alloy membranes using rough polishing/$ZrO_2$ powder filling method demonstrate high hydrogen permeability as well as diffusion barrier efficiency, it leads to the performance improvement in hydrogen perm-selectivity. Our membranes, therefore, are expected to be applicable to industrial fields for hydrogen purification and separation owing to enhanced functionality, durability and metal support/Pd alloy film integration.

• Journal of the Korean institute of surface engineering
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• v.51 no.5
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• pp.277-290
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• 2018

In this study, Pd-Ni-Ag alloy hydrogen separation membranes were fabricated by Pd/Ag/Pd/Ni/Pd multi-layer sputter deposition on the modified MIM(Metal Injection Molding)-PSS(Porous Stainless Steel) support and followed heat treatment. Nickel, used as an alloying element in Pd alloy membranes, is inexpensive and stable material in a hydrogen isotope environment at high temperature up to 1123 K. Hydrogen perm-selectivity of Pd-Ni-Ag alloy membranes is affected not only by composition of membrane films but also by other factors such as surface properties of PSS support, microstructure of membrane films and inter-diffused impurities from PSS support. In order to clarify the effect of surface Ni composition on hydrogen perm-selectivity of Pd-Ni-Ag alloy membranes, the other effects were significantly minimized by the formation of dense and homogeneous Pd-Ni-Ag alloy membranes. Hydrogen permeation test showed that hydrogen permeability decreased from $7.6{\times}10^{-09}$ to $1.02{\times}10^{-09}mol/m{\cdot}s{\cdot}Pa^{0.5}$ as Ni composition increased from 0 to 16 wt% and the selectivity for $H_2/N_2$ was infinite.

• The Research Journal of the Costume Culture
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• v.17 no.1
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• pp.90-104
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• 2009

If people want to project a successful personal style, hair style might play a big role as well as clothing. The purpose of this study was to observe hair behavior according to demographic variables, and to analyze correlation between desired hair image and clothing image sought. Questionnaires were distributed to 600 females aged $20s{\sim}40s$, using a convenient sampling method. Only 556 reliable questionnaires were selected for statistical analysis. Correlation r, ANOVA and Chi-square were used to analyze the data, using the SPSS program. There was a significant association between hair style and occupation. Career woman preferred roll straight perm treated hair, students preferred general perm treated hair and full time house wives preferred general wave perm treated. The medium layer cut was the most preferred cut style. People want to give different accents in hair styling with occupation and age variable. Certain desired clothing image had a high correlation with desired hair style image. Those who people want to express sexy, and bohemian image through clothing, they also want to create those image in hair styling with a high correlation(r=0.683, r=0.704).

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.1960-1962
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• 2004

In this paper, we have studied shielding characteristics of high conductivity or high permeability materials on ELF magnetic fields generated from single or three phase AC line. Perm alloy has been selected as high permeability material and copper as high conductivity material. Four-plate shield (square section) was considered as a shielding shape. We found copper showed stable shielding effects more than perm alloy.

• Journal of the Korean Ceramic Society
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• v.52 no.4
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• pp.269-272
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• 2015

$La_2Ce_2O_7$ and $CeO_2$ membranes were fabricated from the corresponding powders derived from sol-gel process with polyvinyl alcohol binder. These powders and membranes were characterized by XRD, BET, and FE-SEM analysis. Hydrogen and CO gas permeation experiments were performed using Sievert's type equipment. Both fluxes on these membranes were found to decrease with increase of the temperature. This phenomenon was followed by the surface and Knudsen diffusion mechanism. The hydrogen permeability of the $La_2Ce_2O_7$ membrane was found to be $7.27{\times}10^{-5}mol/m^2sPa$, with perm-selectivity of 7.24 at 303 K.