• 대한기계학회논문집A
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• 제30권9호
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• pp.1034-1040
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• 2006

Due to the need of increasing thermal efficiency, supercritical pressure and temperature have been utilized in power plants. It is well known that 9Cr1Mo steel is suitable fer use in power plants operating at supercritical conditions. Therefore, to ensure the safety and the soundness of the power plant, creep characterization of the steel is important. In this study, the creep characterization of the gCr1Mo steel using small punch creep(SP-Creep) test has been described. The applied load and the central displacement of the specimen in SP-Creep test have been converted to bearing stress and strain of uc, respectively. The converted SP-Creep curves clearly showed the typical three-stage behavior of creep. The steady-state creep rate and the rupture time of the steel logarithmically changed with the bearing stress and satisfied the Power law relationship. Furthermore, the Larson-Miller parameter of the SP-Creep test agreed with that of the tensile creep test. From the comparison with low Cr-Mo steels, the creep characteristics of 9Cr1Mo steel proved to be superior. Thus, it can be confirmed that the 9Cr1Mo steel is suitable for supercritical power plant.

• 대한기계학회논문집A
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• 제20권4호
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• pp.1123-1132
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• 1996

It has been reported that high temperature structural components represent the phenomenon of material degradation according to a long term service under high temperature and pressure. Especially, fossile power plant components using the fossil fuel and heavy oil are affected by dewpoint corrosion of $H_2SO_4$produced during a combustion. Therefore, the service materials subjected to high temperature and pressure may occur the stress corrosion cracking. The object of this paper is to investigate SCC susceptibility according to the material degradation of the high temperature structural materials in dewpoint corrosive environment-$H_2SO_4$.The obtained results are summarized as follows : 1) In case of secondary superheater tube, the fractograph of dimple is observed at the concentration of $H_2SO_4$-5%. When the concentration of $H_2SO_4$ is above 10%, the fracture mode is shifted from a transgranular fracture to an quasi-intergranular fracture according to the increment of concentration. 2) In the relationship between [$\Delta$DBTT]$_sp$ and SCC susceptibility, it is confirmed that the greater material degradation degree is, the higher SCC susceptibility is. In addition, it can be known that SP test is useful test method to evaluate SCC susceptibility for high temperature structural components. 3) When [$\Delta$DBTT]$_sp$ is above 17$17^{\circ}C$ the SCC fracture behavior is definitely observed with SCC susceptibility of above 0.4.

• 대한가정학회지
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• 제43권9호
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• pp.97-107
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• 2005

The purpose of this study was to investigate the elementary, middle and high school food service utilization of traditional Korean food in Gwangju and Jeonnam Area dietitians, and to provide basic data for the utilization of traditional food in school food service. The conclusions of this study are as follows. The utilizations of traditional Korean food was remarkable among the dietitians who are elderly, have worked for a long time, are married and in elementary schools. For the elementary, middle and high schools, the utilization of rice was remarkable in Bombop(boiled rice and nuts)(p<.001), Okeukbop(boiled rice mixed with five grains)(p<.001), Potbop(boiled rice and red-bean)(p<.001), Boribop(boiled rice and barley)(p<.01), and Kongbop(boiled rice and beans)(p<.01) The utilization of one-dish meals was remarkable in Kongnamulbop(boiled rice and bean sprouts)(p<.001). The utilization of porridge was remarkable in Hobakjuk(pumpkin porridge)(p<.001) and Potjuk(red-bean porridge)(p<.001). The utilization of noodles was remarkable in Mandu soup(a bun stuffed with seasoned meat and vegetables)(p<.001) and Kalkuksu(cut noodles)(p<.001). The utilization of soup and pot stew was remarkable in Kongnamul soup(p<.001), sagolugeoji soup(p<.001), Calbitang(p<.001) and sullungtang(p<.001), kongbiji stew(p<.01), and soondubu stew(p<.05). The utilization of steamed dish and hard-boiled food was remarkable in green perilla stew(p<.001), fish stew(p<.001) and seasoned and steamed pollack(p<.01). The utilization of pan-boiled food stew was remarkable in small octopus stew(p<.001). The utilization of fried food or grilled food was remarkable in grilled fish(p<.001), bindaetteok(vegetable pancake)(p<.001), fried green pumpkin(p<.001), fried sea food with stone-leek(p<.001) and Buchu fried food(p<.001). The utilization of salad and cooked vegetables was remarkable in spinach salad(p<.001), cucumber salad(p<.001) and Kongnamul(bean sprouts)(p<.05). The utilization of Kimchi was remarkable in Baek kimchi(p<.001), Gat(leaf-mustard) kimchi(p<.001), Youlmu(young radish) kimchi(p<.01) and Oisobaki(p<.01). The utilization of desserts was remarkable in seasonable fruits(p<.001), Kangjung(p<.01), Tteok(rice cake)(p<.01) and Sik Hye(Cinnamon flavored persimmon punch)(p<.01).

• 벤처창업연구
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• 제10권5호
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• pp.45-62
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• 2015

기업가적 지향성의 개념은 "시장기회에 직면한 기업이 혁신적이고 위험을 감수하고 적극적으로 행동하려는 경향성"으로 파악되고 있다. 기업가적 지향성에 대한 연구는 지난 30년 동안 많은 논의를 통하여 개념적인 발전을 이루어 왔으며, 많은 연구자들의 관심을 받아 현재 독자적인 이론 영역을 구축하고 있다. 기업가적 지향성에 대한 초기 연구는 경영성과와 연계되는 메커니즘을 파악하는데 초점을 맞추어 기업가적 지향성의 성과 효과를 파악하는 연구들이 주를 이루고 있으며, 최근에는 이러한 관계를 촉진하거나 혹은 제약하는 상황적인 조건들에 주목하여 다양한 맥락에서 기업가적 지향성이 경영성과를 증대시키는 메커니즘을 파악해 오고 있다. 하지만 비록 기업가적 지향성이 경영성과에 긍정적인 영향을 미친다는 많은 논의들에도 불구하고 기업가적 지향성의 효과들을 종합적으로 파악하고 있는 연구는 많지 않다. 이에 본 연구는 국내외 주요 학술지에 게재된 기업가적 지향성과 관련된 주요 실증연구들을 체계적으로 검토하여 기업가적 지향성의 성과 효과에 대한 기존 연구들을 분류하고 종합하였다. 구체적으로, 본 연구는 우선 기업가적 지향성의 개념을 처음 제안한 Miller(1983)의 최초 연구부터 이를 회고한 Miller(2011)의 연구에 이르기까지 창업론 분야의 주요 저널에 게재된 기업가적 지향성과 경영성과간의 관계를 보고하고 있는 분석결과들을 종합하여 기업가적 지향성의 '주효과'와 관련된 대표적인 연구를 소개하고 기업가적 지향성의 성과 효과가 나타나는 과정을 보다 잘 설명하기 위해 고안된 '매개효과' 연구를 정리하고 비교하였다. 다음으로, 환경특성과 조직특성이라는 주요 상황적 맥락을 기반으로, 기업가적 지향성의 성과 효과를 조절하는 주요 '조절효과' 연구들을 정리하고 종합하였다. 마지막으로, Miller(2011)의 연구에서 제안하고 있는 이론적, 방법론적인 제안을 기반으로 기존 연구들에서 밝혀진 바는 무엇이며, 앞으로 연구되어야 할 부분이 무엇인지에 대해 논의하였다.

• 한국식생활문화학회지
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• 제4권1호
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• pp.83-94
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• 1989

A secondary survey was conducted of 503 customers, to investigate eating out behaviours at five fast food restaurants of Youido apartment compound in Seoul, in April of 1988. The results are summarized as follows: The majority, 84% of customers, were aged 14 to 30, consisting of junior and senior high school children, college students and company employees. In contrast to the previous survey of 1986, in which no elderly customers were found, a small number of elderly customers were observed in this study. The reasons given by customers for patronizing fast food restaurants were the following, from most to least frequent: 'convenient', 'allows for companionship', 'the pleasant place to eat', 'dining equipment and tableware are hygienic', 'to be able to stay as long as I want', and 'foods rapidly served'. Only 24.2% of the customers purchased the fast foods for a full meal, 38.3% purchased the foods for snacking, and others purchased ice cream only or drink only. The majority of the customers ate the purchased foods at the fast food restaurants. However, a limited number of female customers preferred to take the packed fast foods to their homes. Taste preference was a major factor in food selection from available menu items, among the younger customers; whereas customers over 30 years old were concerned with nutritive balance. Fried chicken, pizza, rolled rice with laver, ice cream, and juice were high on the list of liked foods; in contrast, lower preference was for fish burger, doughnut, spaghetti, Chajang noodles and chili beans. The survey discovered that the preference for fried chicken, pizza, and salad had increased compared to the previous survey of 1986. Preference by food nationality was highest for Korean food, then Western food, Chinese food, and Japanese food, in that order. Customers offered suggestions for better fast food service, such as lowering the price; greater variety in the menu; developing fast foods from the traditional Korean foods; and increasing the proportion of vegetables and fruits on the fast food menu. The customers, in particular, emphasized a need for the development of Korean traditional beverage of malt drink and persimmon punch, as well as mungbean pan cakes and sweet- spicy rice noodles (docbokki), as fast foods.