• 한국가스학회지
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• 제7권4호
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• pp.44-52
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• 2003

본 논문은 원자력발전소 방화벽에 설치된 케이블관통부 충전시스템(CPFS: Cable penetration fire stop) 안에서 일어나는 동적 열전달 현상을 수식화하고, 새로운 혼합알고리즘을 이용해서 수치적으로 계산하여, 3차원 그래픽으로 나타내는 작업에 관한 연구이다. CPFS 내에서의 열전도 현상을 주어진 초기조건과 경계조건하에서 포물선 편미분방정식(Parabolic PDE)으로 수식화하였다. 계산을 단순화하기 위하여 전체 열 흐름을 z-축직선상에서의 일어나는 열전도 성분과 x-y-좌표 평면상에서 일어나는 열전도 성분으로 나누었다. z-축과 평행한 직선상에서 일어나는 열전도를 나타내는 PDE는 연속과완화법(SOR: Sequential over-relaxation)을 이용하여 유한불연속 점들에 대한 연립상미분방정식(ODE)으로 만들어서 풀었고, x-y-좌표 평면상에서 일어나는 열전도에 관한 PDE는 Galerkin 유한요소법(FEM: Finite element method)을 적용하여 ODE로 전환해서 풀었다. 여기서 시간과 공간의 함수인 온도는 각 직선상의 점들과 각 평면상의 요소절점들에 대해서 일정한 시간간격으로 초기온도와 경계온도를 업데이트하여 번갈아 가며 계산한다. 이러한 일련의 계산결과를 바탕으로 CPFS시스템 내에서의 온도분포의 동적인 변화를 계산해 낼 수 있었다. 결론적으로 관통하는 케이블이 CPFS시스템의 온도분포에 매우 중요한 역할을 한다는 것을 알 수 있었다. 시뮬레이션 결과는 CPFS내의 온도분포를 쉽게 이해할 수 있도록 3차원 그래픽으로 나타냈으며, 관통하는 케이블이 방화시스템의 온도분포에 매우 중요한 영향을 끼친다는 것을 알 수 있었다. 마지막으로 계산결과를 실험결과와 직접 비교함으로써, 개발된 모델과 계산 알고리즘의 정당성을 보였다.

• 경영과정보연구
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• 제38권1호
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• pp.63-81
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• 2019

기업들은 기존의 웹광고 기법인 베너 광고, 팝업 광고, 삽입 광고 등의 단점들을 극복하기 위해, 이용자들의 거부감을 줄이는 네이티브 광고(native ad)를 적극적으로 활용하고 있다. 네이티브 광고는 이용자들의 거부감을 줄이고 동시에 이목을 이끌어 낼 수 있다는 점에서 유용한 광고기법으로 여겨지고 있으나, 최근에는 전문적인 기사나 동영상 콘텐츠가 광고로 둔갑을 하는 이른바 가짜뉴스, 가짜콘텐츠가 생성되어 그 폐해가 많아 보인다. 이에 본 연구는 웹상에서 기업들이 네이티브 광고를 어떻게 조율하고 통제하는 것이 합리적인 방향으로 기업들의 성과에 기여할 수 있는지에 대하여 파악하고자 하였다. 연구의 검증결과, 광고에 대한 평가가 부정적으로 지각될수록 해당 광고게시물에 대한 설득수준을 저해함과 동시에 해당 광고가 노출되는 웹사이트에도 부정적인 영향을 미칠 수 있다는 것을 파악하였다. 또한, 본 연구는 네이티브 광고기법의 부정적 자극요인들을 중심으로 기업의 질적 성과에 미치는 영향력을 검증한 결과, 정보원의 비전문성이 광고에 대한 의구심에 가장 높은 영향을 미친다는 것을 알 수 있었다. 뿐만 아니라 플랫폼의 정보과잉은 광고에 대한 부정적 평가와 더불어 웹사이트의 평가에도 직접적인 영향을 가진다는 것을 확인할 수 있었다. 아울러 본 연구는 이용자의 웹사이트 관여수준에 따라 경로 간의 차이를 검증함으로써, 세분시장에서 적용될만한 구체적인 시사점들을 제시하였다.

• 한국프랜차이즈경영연구
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• 제13권2호
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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.

• 한국프랜차이즈경영연구
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• 제13권3호
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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.

• 한국환경보건학회지
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• 제17권2호
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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.

• 보건교육건강증진학회지
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• 제28권4호
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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.

• 한국환경과학회지
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• 제26권4호
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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.

• 한국소음진동공학회논문집
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• 제24권6호
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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.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 춘계학술대회 논문집
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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.

• E2M - 전기 전자와 첨단 소재
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• 제10권3호
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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.