• Journal of the Korean Institute of Gas
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• v.7 no.4 s.21
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• pp.44-52
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• 2003

In this work dynamic heat transfer in a CPFS (cable penetration fire stop) system built in the firewall of nuclear power plants is three-dimensionally investigated to develop a test-simulator that can be used to verify effectiveness of the sealant. Dynamic heat transfer in the fire stop system is formulated in a parabolic PDE (partial differential equation) subjected to a set of initial and boundary conditions. First, the PDE model is divided into two parts; one corresponding to heat transfer in the axial direction and the other corresponding to heat transfer on the vertical planes. The first PDE is converted to a series of ODEs (ordinary differential equations) at finite discrete axial points for applying the numerical method of SOR (successive over-relaxation) to the problem. The ODEs are solved by using an ODE solver In such manner, the axial heat flux can be calculated at least at the finite discrete points. After that, all the planes are separated into finite elements, where the time and spatial functions are assumed to be of orthogonal collocation state at each element. The initial condition of each finite element can be obtained from the above solution. The heat fluxes on the vertical planes are calculated by the Galerkin FEM (finite element method). The CPFS system was modeled, simulated, and analyzed here. The simulation results were illustrated in three-dimensional graphics. Through simulation, it was shown clearly that the temperature distribution was influenced very much by the number, position, and temperature of the cable stream, and that dynamic heat transfer through the cable stream was one of the most dominant factors, and that the feature of heat conduction could be understood as an unsteady-state process.

• Management & Information Systems Review
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• v.38 no.1
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• pp.63-81
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• 2019

In order to overcome the disadvantages of banner ad, pop-up ad, interstitial ad, which are existing web advertisement forms, native ad is actively utilized. Native advertising is considered to be a useful advertising technique in that it can reduce users' rejection and attract attention. However, in recent years, there have been a lot of fake news and fake contents that have turned articles or video contents into advertisements. The purpose of this study is to understand how firms can coordinate and control native advertisements in a rational way. For this analysis, we conducted a survey of 308 social media users using quota sampling method. As a result of the verification, it was found that the more negative the perception of the evaluation of the advertisement, the less the level of persuasion about the advertisement and the negative impact on the website where the advertisement is exposed. In addition, this study examined the influence of the negative stimulus factors on the qualitative performance of the firm. As a result, it was found that source non-expert had the highest effect on skepticism on ad. Also, platform overflow has a direct effect on the evaluation of the website as well as the negative evaluation of the advertisement. Moreover, this study provides concrete implications for the subdivision market by verifying the differences between the paths according to the level of website involvement.

• The Korean Journal of Franchise Management
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• v.13 no.2
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• pp.33-51
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• 2022

Purpose: The online market is growing the most in history due to the expansion of non-face-to-face commerce. In addition, as consumers' interest in health, food safety, and environment increases, interest in and consumption of eco-friendly agricultural products is also increasing. Therefore, in the case of a specialty store that sells eco-friendly organic agricultural products, a marketing strategy that can increase customer loyalty by reflecting these consumer needs is necessary. In this study, the store attributes of eco-friendly food stores are classified into location, assortment, price, quality, and employee service, and the effect of each store attribute on utilitarian and hedonic value is investigated. Research design, data, and methodology: The subjects of this study were customers who visited an eco-friendly food store. Of the 511 survey responses, 311 were used for statistical verification, excluding 200 who had not visited within the last 3 months. For statistical analysis, Smart PLS 3.0 was used, and after checking the validity and reliability of the items, hypothesis testing was performed. Result: As a result of the study, it was found that assortment, quality, and employee service among store attributes had a positive (+) effect on utilitarian and hedonic value. Second, location had no significant effect on utilitarian and hedonic value. Third, price did not appear to have a positive (+) effect on the utilitarian value, and it was found to have a positive (+) effect on the hedonic value. Fourth, It was investigated whether the presence or absence of delivery service had an effect on store attributes between utilitarian and hedonic value, and it was found that there was a significant effect between employee service and hedonic value. Conclusions: Among eco-friendly food store environment management will be required in order to provide food that meets the tastes and needs of consumers by diversifying the taste, standard, and quality grade of food, and to maintain or improve the quality. In order to unlike other stores, eco-friendly food stores have high price resistance from the point of view of consumers, so it is necessary to diversify promotional media such as YouTube and SNS to raise awareness of eco-friendly organic food.

• The Korean Journal of Franchise Management
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• v.13 no.3
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• pp.31-43
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• 2022

Purpose: Service quality is a topic of constant interest in marketing research and practitioners. Service quality is an important factor influencing performance even in the context of coffee shops, and research on service quality management strategies continues by coffee shop researchers and practitioners. The service quality of coffee shops is a source of competitive advantage and is an important factor in enhancing customer and business performance. This study aims to identify the effects of cognitive evaluation on emotional and behavioral responses using a cognitive-emotional-behavioral framework and SOR model in the coffee shop context. Cognitive evaluation (service quality) consists of tangibles, responsiveness, assurance, reliability, and empathy dimensions. Research design, data, and methodology: In the proposed model, positive and negative emotions and satisfaction mediate the relationship between service quality and money to spend and visit frequency. The data were collected from customers who visited a coffee shop within the last 1 month. The survey was conducted for about one month. Among a total of 300 distributed questionnaires 261 responses were used for data analysis. The data were analyzed using frequency analysis, measurement model analysis, and structural equation modeling analysis with SPSS 28.0 and SmartPLS 4.0. Results: Tangibles, responsiveness, assurance, and empathy had significant positive effects on positive emotion, while only reliability had a significant negative effect on negative emotion. Both positive and negative emotions had significant positive effects on customer satisfaction, but not on money to spend and visit frequency. Lastly, customer satisfaction had significant positive effects on money to spend and visit frequency. Conclusions: The study revealed the relative weight of cognitive factors on customer emotions and confirmed the validity of SOR model. The fact that tangibility is the most important factor in increasing positive emotions and reliability is the most important factor in reducing negative emotions provides a direction for emotional branding strategies using the service quality mix of coffee shops. This study confirmed the full mediating role of satisfaction between positive and negative emotions and consumer behaviors (money to spend and visit frequency). This infers that when a coffee shop increases customer satisfaction through customer emotion management, the customer's money to spend and visit frequency in the coffee shop increases.

• Journal of Environmental Health Sciences
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• v.17 no.2
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• pp.102-113
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• 1991

This study aimed to find out the effect of freeze-drying leek against cadmium poisoning on the cholesterol and enzyme activities in serum and superoxide radical, SOD and catalase in liver and kidney of the male rats during the administrered period. In this experiment, male rats of Sprague-Dawley strain were used. The rats were divided into 3 groups which were fed differently either for 5 weeks or for 10 weeks:basal diet, basal diet and cadmium in water and 3 % leek added diet and cadmium in water. Cadmium was administered ad libiturn 100 ppm CdCl$_{2}$ in water. The followings are the results of this experiment. 1. Leek reduced the cholesterol and the activities of GPT increase resulted from cadmium treatment. 2. Leek reduced the rate of cadmium in liver and kidney. 3. Leek reduced the activities of SOR and catalase in liver and kidney, while it enhanced the activities of SOD. 4. Leek reduced the necrosis and swelling in liver and kidney casused by cadmium treatment. This experiment showed that leek-addition group had protective effect against cadmium poisoning and increased ALPase activities in serum. Leek alleviated GPT activities in serum and cadmium concentration, necrosis, and swelling in liver and kidney. Therefore, this experiment concluded that leek has defensive power against cadmium poisoning.

• Korean Journal of Health Education and Promotion
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• v.28 no.4
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• pp.63-77
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• 2011

Objectives: This study identifies the meaning of walking and its facilitating factors and barriers from the perspective of urban walkers in Seoul. Methods: The participants consisted of twelve people who either lived or worked in Gangnam district of Seoul. The study applied the data collection process featured in the photovoice, in which the participants took photographs and shared their stories through focus group interviews. Results: Walking is regarded as one of the easiest types of physical activity. While walking, participants find mental tranquility, communication opportunities, and a chance to step back from their everyday lives. Facilitating factors include: access to walking-friendly venues and attractive surrounding environments; the participant's assimilation into the surrounding area; having the feeling of ease and relaxation; and friends and family to walk together. Barriers consist of physical factors such as street design and the busy urban streets, insensitive traffic and low civic awareness, and personal situational factors. Conclusions: The benefit of walking exceeds beyond those of physical health promotion. Actions to encourage walking in urban areas should address the multiple meanings perceived by their citizens.

• Journal of Environmental Science International
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• v.26 no.4
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• pp.447-456
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• 2017

Chemical properties of aerosols were investigated by analyzing the inorganic water-soluble content in $PM_{2.5}$ collected in the downtown area of Jeju City in Jeju Island. Due to an increase in both the number of visiting tourists and the size of local population, the number of cars in this area is increasing, causing an increase in $PM_{2.5}$. Eight $PM_{2.5}$-bound major inorganic ions were analyzed during the summer and winter periods. The water-soluble inorganic component represents a significant fraction of $PM_{2.5}$. In particular, secondary inorganic aerosols contribute 36.2% and 47.5% of $PM_{2.5}$ mass in summer and winter, respectively. Nitrate concentrations increase for $[NH_4{^+}]/[SO_4{^{2-}}]$>1.5, and excess ammonium, which is necessary for ammonium nitrate formation, is linearly correlated with nitrate. These results are clearly observed during the winter because conditions are more conducive to the formation of ammonium nitrate. A significant negative correlation between Nitrogen Oxidation Ratio (NOR) and temperature was observed. The obtained results can be useful for a better understanding of the aerosol dynamics in the downtown area in Jeju City.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.6
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• pp.437-443
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• 2014

Vibration testing is conducted for evaluate the fatigue resistance of responsible system over excitation situations and two kinds of vibration profiles, harmonic or random, are widely used in engineering fields. Harmonic excitation profile is adequate for the rotating machinery that is primarily exposed to the orderly excited force subjected for a rotating speed; Random profile is suitable for the non-stationary vibration input, that is a ground excitation for example. Recently, the sine on random(SOR) testing method was sometimes considered to represent the real excitation conditions since the measured response signals of a target system, expecially for moving mobility, shows usually a mixture of them. So, it is important to understand the accumulated fatigue damage over different excitation patterns, harmonic and/or random, to determine the efficient vibration profile of a target system. A uniaxial vibration testing with a notched simple beam was introduced to evaluate the fatigue damage for different excitation profiles and the best choice of vibration profile was concluded from those comparison of calculated fatigue damages.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.04a
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• pp.340-345
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• 2014

Vibration testing is conducted for evaluate the fatigue resistance of responsible system over excitation situations and two kinds of vibration profiles, harmonic or random, are widely used in engineering fields. Harmonic excitation profile is adequate for the rotating machinery that is primarily exposed to the orderly excited force subjected for a rotating speed; Random profile is suitable for the non-stationary vibration input, that is a ground excitation for example. Recently, the sine on random (SOR) testing method was sometimes considered to represent the real excitation conditions since the measured response signals of a target system, expecially for moving mobility, shows usually a mixture of them. So, it is important to understand the accumulated fatigue damage over different excitation patterns, harmonic and/or random, to determine the efficient vibration profile of a target system. A uniaxial vibration testing with a notched simple beam was introduced to evaluate the fatigue damage for different excitation profiles and the best choice of vibration profile was concluded from those comparison of calculated fatigue damages.

• Electrical & Electronic Materials
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• v.10 no.3
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• pp.233-238
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• 1997

We have investigated gas-detection characteristics of CuTBP (Copper-tetra-tert-butylphthalocyanine) chemiresistor devices exposed to air/200ppm N $O_{2}$ gases. The CuTBP films were made by Langmuir-Blodgett (LB) techniques. Sensitivity, response time, recovery time, and reproducibility of the devices were measured by current voltage characteristics. Interdigital electrode was used to improve the sensitivity. It was observed that a conductance G increases monotonically as the number of interdigital electrode finger pairs increases. As the number of interdigital electrode finger pairs increases, the sensitivity S( $G_{gas}$/ $G_{air}$) increases more than 50 times and stable. But the response time was delayed. The average recovery time of the CuTBP chemiresistor devices turned out to be about 100 second. We have also investigated applicability of the CuTBP chemiresistor device for a gas sensor.sor.