• Journal of Mechanical Science and Technology
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• 제14권10호
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• pp.1143-1150
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• 2000

The effects of ambient conditions on vaporizing sprays from a high-pressure swirl injector were investigated by an exciplex fluorescence method. Dopants used were 2% fluorobenzene and 9% DEMA (diethyl-methyl-amine) in 89% solution of hexane by volume. In order to examine the behavior of liquid and vapor phases inside of vaporizing sprays, ambient temperatures and pressures similar to engine atmospheres were set. It was found that the ambient pressure had a significant effect on the axial growth of spray, while ambient temperature had a great influence on the radial growth. The spatial distribution of vapor phase at temperatures above 473K became wider than that of liquid phase after half of injection duration. From the analysis of the area ratio for each phase, the middle part (region II) in the divided region was the region which liquid and vapor phases intersect. For liquid phase, fluorescence-intensity ratio was greatly changed at lms after the start of injection. However, the ratio of vapor phase was nearly uniform in each divided region throughout the injection.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.472-477
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• 2003

This study was performed to investigate the behavior of vapor phase of fuel mixtures with different piston cavity diameters in a optically accessible engine. The images of vapor phases were measured in the motoring engine using exciplex fluorescence method. The conventional engine was modified as GDI engine with swirl flow. Fuel was injected into atmospheric nitrogen to prevent quenching phenomenon by oxygen. Injection pressure is 5.1MPa. Two dimensional spray fluorescence image of vapor phases was acquired to analyze spray behavior and fuel distribution inside of cylinder. Three injection timings were set at BTDC $180^{\circ}$, $60^{\circ}$and $60^{\circ}$. With a fuel injection timing of BTDC $60^{\circ}$, fuel-rich mixture was concentrated in near the cavity center. With a fuel injection timing of BTDC $60^{\circ}$, fuel-rich mixture level in the center region was highest in the S-type during the late compression stroke. With a fuel injection timing of BTDC $180^{\circ}$, fuel was not affected in a piston cavity and generally distributed as homogeneous mixture.

• 한국조리학회지
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• 제13권2호
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• pp.240-253
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• 2007

The purpose of this study is to crystallize the factors which influence the eating-out tendency at home and work site including in the range of Daegu city. We can find out that taste is the most important element for family eating-out style. Then comes sanitation, service, reputation of a restaurant and price in that order. There are some differences between family eating-out style and workers eating-out style. The only thing that differs from above referred to statement is that price is prior to the reputation of a restaurant. Thus, taste is more important than any other factor in investigative studies. And, in case of family eating-out style, the reputation of a restaurant is prior to price. In case of workers eating-out, however, price is more important than the reputation of a restaurant.

• 대한화장품학회지
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• 제32권4호
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• pp.283-298
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• 2006

본 연구는 최근 급성장하고 있는 국내 한방 화장품 시장을 점검해 보고 여성 소비자들의 화장품 구매행동을 통해 한방화장품이 어떻게 인식되고 있으며, 앞으로 어떻게 육성, 발전시켜 나가야할 것인가를 조사하였다. 서울에 거주하는 20세${\sim}$50세 성인 여성 소비자를 대상으로 설문조사를 실시했으며, 총 400부의 설문지를 배포하여 회수된 설문지 중 344부를 분석하여 유의적인 통계결과를 얻을 수 있었다. 이 결과를 토대로 본 연구에서는 한방 화장품의 시장 현황과 사용실태에 대한 기초 정보 제공을 통해 소비자의 요구를 보다 직접적으로 파악함으로써 한방 화장품 시장에 대한 마케팅 전략 수립 시 기초 자료가 될 것으로 사료된다.

• 대한기계학회논문집A
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• 제28권4호
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• pp.453-459
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• 2004

25Cr-20Ni series strainless steels have an excellent high temperature strength high oxidation and high corrosion resistance. However, further improvement can be expected of creep strength by work hardening prior creep. In the present study, the effect of prestraining at room temperature on the creep behavior of a Class M(STS310S) and a Class A(STS310J1TB) alloy containing precipitates have been examined. Prestaining was carried out at room temperature and range of prestrain was 0.5-2.5 % at STS310J1TB and 2.0-7.0% at STS310S. Creep behavior and creep rate of pre-strained specimens were compared with that of virgin specimens. Room temperature prestraining produced the creep life that is longer than that of a virgin specimen both for STS310J1TB and STS310S when creep test was carried out at the temperature lower than recrystallization temperature. The reason for this improvement of creep life was ascribable to the interaction between dislocations and precipitates in addition to the dislocation-dislocation interaction in STS310J1TB and the dislocation-dislocation interaction in STS310S. The beneficial effect of prestraining in STS310J1TB was larger than that of STS310S.

• 한국공간구조학회논문집
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• 제9권4호
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• pp.73-80
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• 2009

성능에 기초한 내진설계에서 구조물의 지진에 대한 성능평가를 위하여 구조물의 비탄성 지진거동을 정확하게 예측하는 젓이 중요하다. 정확한 시스템의 연성능력 평가를 위해서는 각부재의 하중과 변형의 관계를 보다 실제적으로 규정하는 것이 중요하다. 비선형 해석에 의한 구조물의 비탄성 거동 파악을 위해서 단순화된 부재의 하중-변형 관계 모델을 적용한다면 구조물의 실제적이고 정확한 거동을 예측하기에는 어려움이 있다. 본 논문에서는 하중-변형 관계를 Backbone 이력모델을 적용하여 단순화된 하중-변형 관계를 적용한 모델과 시스템연성능력 및 층연성능력을 비교, 평가하였다. 해석결과로 이선형 이력모델의 경우에 시스템 및 층 연성도의 과소평가는 실제구조물의 소성거동을 과소평가하는 곁과를 초래하며 보다 정착한 비선형해석을 위하여 부재의 이력모델은 Backbone 이력모델을 사용하는 것이 바람직하다.

• 한국수소및신에너지학회논문집
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• 제21권2호
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• pp.123-128
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• 2010

Hydriding combustion synthesis (HCS) can produce full hydrides of alloys and in a short time. The conventional process based on ingot metallurgy cannot produce Mg-based alloy easily with the desired composition and the cast product needs a ling activation process for the practical use of hydrogen storage. In this study, the hydriding properties of Mg-xNi (x=5, 13.5, 54.7wt.%) alloys prepared by hydriding combustion synthesis were evaluated. The hydrogen storage capacity and kinetics of HCS Mg-xNi alloys were strongly dependent on the content of Ni. The HCS Mg-13.5wt.%Ni alloy shows the hydriding behavior to reach the maximum capacity within 30 min. and the reversible $H_2$ storage of 5.3wt.% at 623 K.

• 대한가정학회지
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• 제26권4호
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• pp.31-41
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• 1988

The purpose of the present study was to test the behavior of dietary life, the preception of body image and the attitude of body weight control of the subjects, and to imagine difference of value evaluation about thirteen foods. the subjects were 570 high school students who were living in Seoul. The results can be summarized as follows: 1. In selecting actual and ideal body sizes from a series of five outline drawings of female figures that ranged form 20% underweight to 20% overweight, 64% of the subjects selected overweight drawing s as their actual sizes, and 85.1% of the subjects selected underweight ones as the ideal sizes. 59.3% of the subjects had a desire to lose weight, 20.8% to gain weight. Those who think they are thinner than standard body weight were more satisfied with their body sizes than those who think they are fatter than that. Most subjects (79.8%) were concerned about their weight control, and the majority of them (36.1%) began to take concerns about it in their high school days, through the conversation with their friends about their body sizes. 2. In this study, thirteen foods were chosen as samples; rice, bread, salad, milk, cola, cider, juice, duck-bok-ki, chocolate, batterfriend foods, chinese noodles, cookies, fruits. Most of them evaluated foods on the basis of the taste. They valued fruits over any other foods as least fattened food, while they thought of such foods as rice, cola, cider, ice-cream, chocolate, batter-fried food, chinese noodles as fattened foods.

• 산경연구논집
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• 제10권2호
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• pp.39-49
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• 2019

Purpose - Customer loyalty and citizenship behavior are key success factors of franchise system. They make the management of franchisee more effective and efficient. Prior studies, however, mainly dealt with only acquisition utility of customer, such as perceived product/service quality and brand reputation to explain customer loyalty and citizenship behavior, which explains only on one side. We tried to investigate the effect of exchange utility of customer, such as relationship strength and psychological obligation together with the acquisition utility. In addition, we tried to investigate the relationship between customer loyalty and citizenship behavior in franchise context. Research design, data, and methodology - This study used data collected from the dining franchisee managers of 342 franchisors in South Korea. The franchisors consist of more than ten franchisees, the majority of which participated directly in the transaction with franchisor and have worked for more than six months. To test the hypotheses, the study used structural equation model analysis. Results - H1-1, 1-2, 1-3 predicted that acquisition utility would increase customer loyalty to franchisee. In support of H1-1, 1-2, 1-3, the results indicated that acquisition utilities such as perceived product value, perceived service value, and franchise brand reputation had positive effects on customer loyalty. H2-1, 2-2 predicted that exchange utility would increase customer loyalty to franchisee. In support of H2-2, the result indicated that psychological obligation had positive effects on customer loyalty like other acquisition utilities. However, H2-1 was not supported. Relationship strength had no significant effect on customer loyalty. H3 predicted that customer loyalty would increase customer citizenship behavior. In support of H3, the results indicated that customer loyalty had positive effect on customer citizenship behavior. Overall, the evidences generally supported the hypotheses. Conclusion - The results of the study show that not only acquisition utility but also exchange utility increases customer loyalty to franchisee and also show that customer loyalty increases customer citizenship behavior. Interestingly, however, relationship strength has no significant effect on customer loyalty. These results have two implications. The one is that increasing exchange utility can improve customer loyalty as acquisition utility can. The other one is that both of customer utilities can improve customer citizenship via customer loyalty.

• 한국산학기술학회논문지
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• 제18권2호
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• pp.277-286
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• 2017

본 연구는 간호사의 희망과 감사성향, 일터영성이 조직시민행동정도를 파악하고, 조직시민행동에 미치는 영향요인을 분석하여 바람직한 간호조직문화를 형성 및 증진시켜 간호조직의 효율적이고 경쟁력 있는 인적자원관리방안을 제시하고, 중재방안을 마련하는데 기초자료를 제공하고자 시도되었다. 서울 및 경기도 소재 종합병원 이상의 4개 병원에서 근무하는 간호사 147명을 대상으로 설문조사하였고, 수집된 자료는 SPSS 18.0 프로그램을 이용하여 t-test와 ANOVA, Person's correlation coefficients, multiple stepwise regression으로 분석하였다. 연구결과 간호사의 희망(${\gamma}=.22{\sim}.36$, p<.001), 감사성향(${\gamma}=.38$, p<.001), 일터영성(${\gamma}=.38{\sim}.54$, p<.001), 조직시민행동 간에는 정적 상관관계를 보였다. 또한, 일터영성(${\beta}=.54$, p<.001), 이직희망(${\beta}=.12$, p<.001), 희망(${\beta}=.09$, p<.001), 감사성향(${\beta}=.08$, p<.001)은 조직시민행동에 유의한 영향을 주었으며, 설명력은 41.6%이었다. 본 연구는 간호조직에서 아직 초기단계의 연구가 진행되고 있는 일터영성에 대한 기초이론을 체계화하였고, 간호사의 조직시민행동을 유발시키기 위해 간호사의 희망, 감사성향, 일터영성을 높일 수 있는 다양한 교육 프로그램과 지원 제도가 요구된다.