• Journal of Korea Society of Waste Management
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• v.34 no.5
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• pp.518-527
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• 2017

The development of renewable energy is currently strongly required to address environmental problems such as global warming. In particular, biomass is highlighted due to its advantages. When using biomass as an energy source, the conversion process is essential. Fast pyrolysis, which is a thermochemical conversion method, is a known method of producing bio-oil. Therefore, various studies were conducted with fast pyrolysis. Most studies were conducted under a lab-scale process. Hence, scaling up is required for commercialization. However, it is difficult to find studies that address the process analysis, even though this is essential for developing a scaled-up plant. Hence, the present study carries out the process analysis of biomass pyrolysis. The fast pyrolysis system includes a biomass feeder, fast pyrolyzer, cyclone, condenser, and electrostatic precipitator (ESP). A two-stage, semi-global reaction mechanism was applied to simulate the fast pyrolysis reaction and a circulating fluidized bed reactor was selected as the fast pyrolyzer. All the equipment in the process was modeled based on heat and mass balance equations. In this study, process analysis was conducted with various reaction temperatures and residence times. The two-stage, semi-global reaction mechanism for circulating fluidized-bed reactor can be applied to simulate a scaled-up plant.

• Journal of Fashion Business
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• v.19 no.1
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• pp.106-121
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• 2015

The purpose of this study is to classify the attitudes toward fast fashion into groups and analyze the differences of the self-consciousness, and make-up behavior by groups. Questionnaires are being administered from 179 high school girls living in Deagu metropolitan City. Frequency, factor analysis, reliability analysis, cluster analysis, ANOVA, Duncant-test, and ${\chi}^2$-test are all used for data analysis. Our findings are as follows. The attitude toward fast fashion shows a significant correlation with the sub-variable self-consciousness and make-up behavior. Attitude toward fast fashion is being categorized into convenience focus, fashion focus, design focus, and season focus. Self-consciousness is social self-consciousness, social anxiety, private self-consciousness, and private anxiety. Make-up behavior is positive effect, fashion leader, and conformity. Attitude toward fast fashion is classified into three groups: disposability, fashionability, and low interest of fashion. The groups show a significant difference in the self-consciousness, and make-up behavior. Groups display no distinctions between the sub-variables in the actual conditions of cosmetics such as a first time for make-up and frequence of visit.

• Journal of Biomedical Engineering Research
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• v.15 no.4
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• pp.395-400
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• 1994

High resolution spectral analysis is essential for ECG anaysis. The fast Fourier transform has been widely used for frequency analysis of ECG signals but this procedure provides poor resolution when the data record is short and shows Gibb's phenomena. The ARMA FTF (Fast Transversal Filter) algorithm is used for high resolution spectral analysis. The reason of unsalability of this algorithm is investigated and the method for improving the numerical stability is proposed. The proposed algorithm is applied to spectral analysis of the ECG. Since this result has less variations than the FFT based results, it can be used for the computerized diagonosis of the ECG.

• Nuclear Engineering and Technology
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• v.55 no.7
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• pp.2366-2372
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• 2023

Are borate and silicate glasses suitable for working as shieling materials against fast neutrons? To correctly answer the above question, some silicate, and borate-based glasses were fabricated and irradiated with various doses of fast neutrons varied between 1.73 and 12.10 MGy. The color and hardness of the fabricated glasses were affected by the fast neutron fluence where the transparent glasses turned colored as well as the hardness of the fabricated glasses was decreased. The gamma-ray spectrometric analysis shows a high activity concentration produced in the barium borate glasses due to the formation of radioisotopes Ba-131 and Ba-133 reaches to 5.92E+05 Bq and 4.25E+03 Bq, respectively for sample Cd-5 Batch 3. Additionally, the gamma-ray spectrometric analysis for the sodium silicate glasses shows low activity concentrations emitted from isotopes formed due to the activation of Y₂O₃-associated impurities. These activities are low compared to that emitted by barium borate-based glasses.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.6
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• pp.483-488
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• 2007

The aerodynamic characteristics of FAST(Future Air Speed Transit) combined the body with tandem wing flying over nonplanar ground surface are investigated by using a boundary element method. To validate the present method, results of the present analysis are compared with the experiment and other numerical results. The arrangement of the tandem wing is determined to secure sufficient aero-levitation force and the stability through the analysis of the aerodynamic characteristics of the FAST. The FAST has the maximum lift characteristics when the tandem wing with lower endplate is located at the front side and the rear side of the body. The stability of the FAST can be secured by using the flaperon of the tandem wing.

• The Korean Journal of Food And Nutrition
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• v.26 no.2
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• pp.301-309
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• 2013

This study was designed to provide fundamental data on the consumption of fast food for a balanced diet of university students. The effects of personal characteristics and preferences such as gender, major, residing region, living expense, school grade, dieting, physical activity, smoking and alcohol consumption on fast food consumption patterns were analyzed by surveying university students. The analysis showed significant differences (p<0.05) in the consumption of different types of fast food depending on different personal characteristics and preferences as follows : hamburger by major, physical activity and alcohol consumption; chicken by school grade, physical activity and alcohol consumption; spaghetti by gender and smoking. Groups of different majors and school grades showed significant differences (p<0.05) in response to a question "Have you ever eaten fast food for regular meals?". The choice of fast food types based on taste and price appeared to be significantly influenced by majors and gender. Different groups with different majors and dieting experience appeared to think significantly differently about fast food. In response to a question "Has the consumption of fast food changed your diet style" different groups of different majors and physical activities showed significant differences. The analysis of factors affecting fast food choices revealed that fast food is chosen significantly differently depending on gender and majors (p<0.05). The purchase of fast food appeared to be significantly affected by gender, diet, physical activity, experience of fast food and consumption of fast food for regular meals (p<0.05).

• The Korean Journal of Food And Nutrition
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• v.28 no.1
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• pp.119-125
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• 2015

This study was analyzed to provide fundamental data on the relationship between fast food consumption behaviors and food-related lifestyle types. Data was collected from 268 middle students in the Incheon region through a self-administered questionnaire. A factor analysis extracted five comprising food-related lifestyle, which we named health seeking (factor 1), taste seeking (factor 2), easy seeking (factor 3), popularity seeking (factor 4) and safety seeking (factor 5). According to the results of the factor analysis, the food-related lifestyle showed that the average consumption was more than 2.95 and, 0.792 in Cronbach alpha coefficient. There were significant differences in the influence factor for the selection of fast food according to taste seeking and, popularity seeking types (p<0.05). Also, the easy seeking and safety seeking lifestyle types showed a significant differences for the reason the choosing criteria of fast food (p<0.05). Especially, the nutrition problem was of the highest importance for the health and safety seeking but an advertisement effect trend appealed more to the taste seeking, easy seeking and popularity seeking lifestyles. There were significant differences in fast food of intake frequency according to health seeking, easy seeking, popularity seeking and safety seeking types (p<0.05). A significant positive result of the internal characteristics of fast food consumption (p<0.05) was shown for the health seeking and safety seeking types. A significant positive result of the external characteristics of fast food consumption (p<0.05) was shown for the popularity seeking and safety seeking types.

• The Research Journal of the Costume Culture
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• v.28 no.2
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• pp.147-165
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• 2020

To identify the antecedents of repurchasing intention toward fast fashion brands, this study was conducted to examine brand authenticity and brand identification as both direct and indirect antecedents of repurchasing intention through fast fashion brand love. Through convenience sampling, 266 university students in Seoul metropolitan area completed a questionnaire survey. Data were analyzed using SPSS for exploratory factor analysis, and AMOS was used for confirmatory factor analysis and path analysis. Factor analysis revealed the following: for brand authenticity, four dimensions('originality,' 'reliability,' 'continuity,' and 'naturalness') were revealed; for both consumer brand identification and repurchase intention one dimension was revealed; and for brand love two dimensions were revealed('passion' and 'affection'). Path analysis confirmed that 'reliability' and 'naturalness'in relation to brand authenticity indirectly influenced repurchase intention through 'passion'(as a factor of brand love) and directly influenced repurchase intention. Further, 'continuity' in relation to brand authenticity indirectly influenced repurchase intention through 'affection'(as a factor of brand love) and directly influenced repurchase intention. Consumer brand identification influenced repurchase intention indirectly through two factors of brand love. These results suggest that fast fashion brand marketers should implement effective strategies that consider consumers'perceptions of brand authenticity, consumer brand identification, and brand love.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1420_1422
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• 2009

Lightning currents are one of major influences on the dynamic performance of counterpoise. High lightning current causes the dynamic grounding performance of counterpoise due to very fast fronted pulses. The previous analysis has often been based on quasi-static approximation that can not be applicable to very fast fronted pulses. To extend the analysis for fast fronted pulses in this paper, the full-wave analysis method based on the rigorous electromagnetic-field theory approach is used and the effects of the ionization of the soil are disregarded. Based on the simulation results, the empirical formulas applicable for slow and fast fronted lightning current pulses are reviewed; therefore, the validity of the theoretical approach is verified through comparison between the calculated and measured results.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.05a
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• pp.63-66
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• 2009

Lighting currents are one of major influences on the dynamic performance of ground electrodes. High lighting current intensity changes in the dynamic grounding performance due to ionization of the soil and very fast fronted pulses. The previous analysis has often been based on quasi-static approximation that is not applicable to very fast fronted pulses. To extend the analysis to fast fronted pulses in this paper, the full-wave analysis method based in the rigorous electromagnetic-field theory approach is used and the effects of the ionization of the soil me disregarded. Based on the simulation results, the empirical formulas applicable for slow and very fast fronted lightning current pulses me reviewed; therefore the validity of the theoretical approach is verified through comparison between the calculated and measured results.