• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.4
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• pp.336-345
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• 2012

In crack growth life, uncertainties are caused by variance of geometry, applied loads and material properties. Therefore, the reliability estimation for these uncertainties is required to keep the robustness of calculated life. The stress intensity factors are the most important variable in crack growth life calculation, but its equation is hard to know for complex geometry, therefore they are processed by the finite element analysis which takes long time. In this paper, the response surface is considered to increase efficiency of the reliability analysis for crack growth life of a turbine wheel. The approximation model of the stress intensity factors is obtained by the regression analysis for FEA data and the response surface of crack growth life is generated for selected factors. The reliability analysis is operated by the Monte Carlo Simulation for the response surface. The results indicate that the response surface could reduce computations that need for reliability analysis for the turbine wheel, which is hard to derive stress intensity factor equation, successfully.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.10a
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• pp.267-273
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• 2004

This paper targets to define controlling factors of pressure-coupled combustion response and estimate their effects on droplet evaporation process. Dynamic characteristics of hydrocarbon propellant vaporization perturbed by acoustic pressure are numerically simulated and analyzed. 1-D droplet model including phase equilibrium between two phases is applied and acoustic wave is expressed by harmonic function. Effects of various design factors and acoustic pressure on combustion response are investigated with parametric studies. Results show that driving frequency of acoustic perturbation and ambient pressure have important roles in determining magnitude and phase of combustion response. On the other hand, other parameters such as gas temperature, initial droplet size and temperature, and amplitude of acoustic wave cause only minor changes to magnitude of combustion response. Resultant changes in phase of heat of vaporization and thermal wave in droplet highly influence magnitude and phase of combustion response.

• The Plant Pathology Journal
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• v.26 no.2
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• pp.110-114
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• 2010

WRKY transcription factors are known to be involved in many different biological processes including plant response to biotic stress, abiotic stress, and plant development. WRKY proteins are extensively studied in Arabidopsis. Recently, reports on WRKY proteins are rapidly increasing in the other plant species, especially in rice. Therefore, this review will discuss the function of rice WRKY proteins reported so far.

• Annals of Clinical Neurophysiology
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• v.22 no.1
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• pp.8-12
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• 2020

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an immune-mediated neuropathy with heterogeneous features. Appropriate treatment will produce a favorable outcome, but a poor treatment response and severe disability have also been reported. The roles of the clinical phenotypes and electrophysiological features of CIDP as well as of autoantibodies against nodal and paranodal proteins have been highlighted previously due to their association with the treatment response and long-term prognosis. This review addresses the diverse factors associated with the prognosis of CIDP.

• Bulletin of the Korean Chemical Society
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• v.18 no.7
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• pp.703-706
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• 1997

Response surface method was applied to the predicting optimum conditions of benzene synthesis for radiocarbon dating. The weight of carbon dioxide, the temperature of lithium container for producing acetylene and the activation temperature of catalyst which was used for the cyclization of acetylene to benzene were used as experimental factors. The yields of benzene synthesis were measured from twelve experiments which were carried out under various experimental conditions. The polynomial equation was obtained by using three experimental factors and yields. The validity of polynomial equation was confirmed by comparing the calculated yields with the experimental ones.

• Korean Chemical Engineering Research
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• v.54 no.1
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• pp.44-51
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• 2016

The powder core, conventionally fabricated from iron particles coated with insulator, showed large eddy current loss under high frequency, because of small specific resistance. To overcome the eddy current loss, the increase in the specific resistance of powder cores was needed. In this study, copper oxide coating onto electrically conductive iron particles was performed using a planetary ball mill to increase the specific resistance. Coating factors were optimized by the Response surface methodology. The independent variables were the CuO mass fraction, mill revolution number, coating time, ball size, ball mass and sample mass. The response variable was the specific resistance. The optimization of six factors by the fractional factorial design indicated that CuO mass fraction, mill revolution number, and coating time were the key factors. The levels of these three factors were selected by the three-factors full factorial design and steepest ascent method. The steepest ascent method was used to approach the optimum range for maximum specific resistance. The Box-Behnken design was finally used to analyze the response surfaces of the screened factors for further optimization. The results of the Box-Behnken design showed that the CuO mass fraction and mill revolution number were the main factors affecting the efficiency of coating process. As the CuO mass fraction increased, the specific resistance increased. In contrast, the specific resistance increased with decreasing mill revolution number. The process optimization results revealed a high agreement between the experimental and the predicted data ($Adj-R^2=0.944$). The optimized CuO mass fraction, mill revolution number, and coating time were 0.4, 200 rpm, and 15 min, respectively. The measured value of the specific resistance of the coated pellet under the optimized conditions of the maximum specific resistance was $530k{\Omega}{\cdot}cm$.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.1
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• pp.143-152
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• 2002

European side impact analysis of an electric vehicle was done using the robust design method. In order to minimize VC as well as rib deflection, the injury response table which consists of rib deflection and VC response table has been introduced. The sensitivities and interactions are almost the same when it was compared with those of rib deflection and VC response table. Using internal energy of the factors, the starting time of dummy rib deflection and the contact average velocity, the internal energy and time-velocity response table were introduced. It is shown that the results of the new response tables have the similar characteristics to those of the Injury response table. It is suggested that the internal energy and time-velocity response table should be utilized to minimize injuries.

• Korean small business review
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• v.41 no.3
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• pp.151-172
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• 2019

The changes in the 4th industrial revolution era are not limited to specific sectors, but affect all sectors of industry. Thus all companies are required to respond effectively to changes. Some companies response by adopting cutting-edge ICT and some companies improve the organizational structure, or enhance the competence of individual employees. This study is based on the assumption that the responses to the change in the 4th industrial revolution era should not be uniform, and that the response strategies and priorities should vary according to the characteristics of the companies. The purpose of this study is to suggest both different response strategies and the priority of the responding factors(areas) to small and medium-sized enterprises. Data were collected through the semi-Delphi method. As a result of data analysis, the priorities of the medium-sized enterprises were as follows: introduction of IT-strengthening the competence of the individuals - establishing technology infrastructure-improving organizational structure - efficiency of work - improving organizational culture. While the priorities of the response factors(area) of the small-sized companies were as follows: strengthening the competence of the individuals - efficiency of work - introduction of IT - establishing technology infrastructure - improving organizational structure - improving organizational culture.

• Bulletin of Food Technology
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• v.15 no.4
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• pp.29-35
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• 2002

To prevent the incidence of type food allergies, removal of food allergens by excluding all foodstuffs containing the allergen(s) or disruption of allergen(s) using proteases has been employed. Though allergen- specific digestion with a protease worked well in the preparation of low allergenic goods, it is often difficult to destroy allergenicity without adversely affecting the nutritive value, taste and rheological properties of foods. In the present study, we represented that herbs component contained both allergy- enhancing and inhibiting factors, in addition to llergens. We also reported that herbal component such as epigallocatechingallate (EGCG) and epicatechingallate (ECG) is possible to be allergy- inhibiting factors, but the exact mechanism by which they alleviate allergic response is left to be clarifying. Document of allergy enhancing factors and enrichment of allergy inhibiting factors may provide a new approach to diminish allergenicity of various foodstufffs. Clarification of the allergic reaction modifying mechanism of food components and optimization of the intake of allergy modifying factor are necessary for decrement of allergenicity of conventional food and prevention of incidents of allergic response

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.934-938
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• 2000

Built-up edge affects the surface integrity of the machined surface and tool wear. Tool geometry and cutting conditions are very important factors to remove BUE. In this paper, we optimized the geometry of the metal slitting saw .1nd cutting conditions to remove BUE by the experiment. In general, the metal slitting saw is plain milling cutter with thickness less of a 3/16 inch. This is used for cutting workpiece where high dimensional accuracy and surface finish are necessary. The experiment was planned with Taguchi method that is based on the orthogonal array of design factors(coating, rake angle, number of tooth, cutting speed, feed rate). Response table was made by the value of the surface roughness, the optimized tool geometry and cutting conditions through response table could be determined. In addition. the relative effect of factors were identified by the variance analysis. filially. coating and cutting speed turned out important factors.