• Journal of Nutrition and Health
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• v.45 no.6
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• pp.588-599
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• 2012

There is a limitation to estimate vitamin $B_{12}$ intake due to the lack of data on vitamin $B_{12}$ content of Korean commercial foods. In this study, vitamin $B_{12}$ content was determined in favorite Korean restaurant foods, convenient or instant foods, fast foods and bakery products through a modified microbioassay using Lactobacillus delbrueckii ATCC 7830. Bulgogi and seafood & green pepper griddle had high vitamin $B_{12}$ content, 3.50 and $2.96{\mu}g$/100 g, respectively. Pork suyook, pork griddle and pollack griddle had 0.48, 0.31 and $0.32{\mu}g$/100 g of vitamin $B_{12}$, respectively. In stew, soft-tofu stew with seafood and doenjang stew with seafood had relatively high vitamin $B_{12}$ content, 1.93 and $1.44{\mu}g$/100 g, respectively. Bibimbap and 4 different types of rice porridge, beef & mushroom, chicken & ginseng, seafood or abalone, had 0.36, 0.08, 0.09, 1.64 and $0.13{\mu}g$/100 g of vitamin $B_{12}$, respectively. One serving of haejanggguk, yookejang, chuotang and galbitang had 5.97, 2.04, 2.63 and $1.91{\mu}g$ of vitamin $B_{12}$, respectively. One serving of samgetang and sulongtang had $2.89{\mu}g$ and $6.64{\mu}g$ of vitamin $B_{12}$. In noodles, one serving of cram noodle soup, bibim-nangmyeon, and mul-nangmyeon had 18.8, 1.21 and $0.38{\mu}g$ of vitamin $B_{12}$, respectively. One regular gimbap and one triangle gimbap contained 1.09-2.53 and $0.54-1.11{\mu}g$ of vitamin $B_{12}$, respectively. One cheese-burger, chicken-burger and bulgogi-burger had 0.76, 0.62 and $0.54{\mu}g$ of vitamin $B_{12}$, respectively. A plain bagel and a waffle contained 0.13 and $0.17{\mu}g$/100 g of vitamin $B_{12}$, respectively. Ready-made tomato sauce or cream sauce for spaghetti in a retort pouch contained only a trace of vitamin $B_{12}$. In conclusion, these results should contribute to improving the present food vitamin $B_{12}$ content database, most of which were cited from foreign data, thereby it could be helpful to estimate the vitamin $B_{12}$ intake of Koreans more accurately than before. It will also provide new information for dietary education related to vitamin $B_{12}$ and health.

• Tunnel and Underground Space
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• v.14 no.1
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• pp.69-77
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• 2004

Investigation of the time-dependent behavior of rock and the associated mechanisms are of key interest in long-term stability analysis of many engineering applications. In this study, creep tests were performed on Daejeon granite samples of 25.4mm diameter under uniaxial compression at varying stress levels. The effect of moisture was investigated by testing both air-dried and fully water-saturated samples. The creep behavior of Daejeon granite exhibited three distinctive stages of primary, secondary and tertiary creep. The ultimate strength of granite under a constant stress decreased considerably with time. Saturation and immersion of the test specimen in water markedly increased the total creep strain as well as the secondary creep rate. The experimental creep curves are fitted to Burger's model as well as two other empirical models suggested by previous researchers. A number of the parameters determined for each model are dependent on stress and influenced by the presence of water. Based on the experimental results, an empirical relation between the applied stress and the time-dependent strain is established separately for each air-dried and fully water-saturated Daejeon granite.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2001.11a
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• pp.102-115
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• 2001

국내 분화류의 생산면적은 2000년 현재 1,036.2ha이며 생산량은 연간 282,656천분, 그리고 생산액은 연간 268,498,990천원으로 추산되고 있다(2000년 화훼재배현황, 농림부). 이와 같은 국내 분화재배면적이 증가함에 따라 다양한 화종의 분화가 재배되고 있으며 화종에 따른 관수방법, 이용상토, 양액농도, 시비방법 등에 대한 많은 연구가 이루어지고 있다(Lieth and Burger, 1989). (중략)

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.4
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• pp.953-959
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• 1990

본 연구에서는 임의의 순간에서 난류유동장의 난류구조를 해석하기 위하여 Lumley의 특성 에디 분배법을 이용하였다. 이때 난류구조의 해석은 비등질성의 K-L 전개와 등질성의 푸리에 전개로 표현하여 그 수렴성, 레이놀즈 수의 영향 등 여러가지 특성을 연구하였다. 본 연구에서 선정한 비등질성 난류유동장은 Chambers등이 연구 한 랜덤력을 갖는 Burgers 방정식을 수치적으로 풀어서 얻었다. 이와 같은 난류유동 장을 K-L전개와 푸리에 전개로 표현할 때에 수렴성은 레이놀즈 수가 서로 다르고 또한 전개항의 수가 다를 때에 RMS 오차를 가지고 비교하였다.여기서 푸리에 전개 계수 들은 Galerkin 방법으로 구하였다.

• Journal of applied mathematics & informatics
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• v.37 no.5_6
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• pp.429-442
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• 2019

This article addresses the influence of partial slip condition in the hydromagnetic flow of Burgers fluid in a rotating frame of reference.The flows are induced by oscillation of a boundary. Two problems for oscillatory flows are considered. Exact solutions to the resulting boundary value problems are constructed. Analysis has been carried out in the presence of magnetic field. Physical interpretation is made through the plots for various embedded parameters.

• The Journal of Engineering Geology
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• v.13 no.2
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• pp.227-238
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• 2003

Understanding of a creep behavior in rocks under a constant load, due to visco-elastic properties of rock, is an essential element to predict a long term ground deformation. In order to clarify the creep characteristics of the mudstone in Duho formation at Pohang basin, deposited during Tertiary, a series of laboratory tests including physical properties, unconfined compressive strength and uniaxial creep tests, was performed. The mudstone showed a higher creep potential due to 26% of clay minerals such as illite and chlorite. The unconfined compressive strength of the rock was $462{\;}kg/\textrm{cm}^2$ in average, and four creep tests were performed under constant stress of 40 to 70 % of the strength. The creep constants in the empirical and theoretical equations were deduced from the time-strain curves obtained from the tests. Among the several equations, the empirical equation proposed by Griggs and theoretical equation of Burger’s model are appreciated as the best one to express the creep behavior of the mudstone. Instantaneous elastic strain was linearly increased with stress level but strain velocity during the first creep is decreased with a similar pattern by time lapse regardless the stress level.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.8
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• pp.20-28
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• 2004

For the prediction on the onset of oblique shock wave-induced vortex breakdown, computational studies on the Oblique Shock wave/Vortex Interaction (OSVI) are conducted and compared with both experimental results and analytic mode1. A Shock-stable numerical scheme, the Roe scheme with Mach number-based function (RoeM), and a two-equation eddy viscosity-transport approach arc used for three-dimensional turbulent flow computations. The computational configuration is identical to available experiment, and we attempt to ascertain the effect of parameters such as a vortex strength, streamwise velocity deficit, and shock strength at a freestream Mach number of 2.49. Numerical simulations using the k-w SST turbulence model and suitably modeled vortex profiles are able to accurately reproduce many fine features through a direct comparison with experimental observations. The present computational approach to determine the criterion on the onset of oblique shock wave-induced vortex breakdown is found to be in good agreement with both the experimental result and the analytic prediction.

• Journal of the Korea Furniture Society
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• v.19 no.3
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• pp.180-192
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• 2008

The historian called Peter Burger divided it into historical avant-garde before and after the first World War (Dadaism, Futurist, Geometric Abstract, etc.) and Neo- avant-garde during the period of forming social foundation that would be ready to accept new forms of art in the USA, the center of capitalism, after the 2nd World War such as pop art and conceptual art including the then emerging avant-garde minimal art. Meanwhile, he interpreted that Neo- avant-garde succeeded the spirit of historical avant-garde. For modem furniture, the avant-garde terminologies are discussed from the aspect of epistemology or symbolism. On the other hand, they would be exclusively used for advertising slogans, however, it is considered as difficult due to vague terms or their characteristics. This study relates the points of historians such as Peter Burger for theoretical proposal and Richard Kostelanetz's point for formal issues, and contracts and arranges the avant-garde terminologies and its characteristics to the meaning of "getting out of the present decadent trend - aiming for future", "transcending the present aesthetic custom - renovation" and "violating the rules already established in the process of entering new areas - freshness of unfairness". The study was meaningful in providing fundamental clues based on the historical discussion and artists for Neo- avant-garde in the 1960s, that is, the mainstream of design at the end of the 20th century in the period when an avant-garde oriented alternative in the 21st century design has been sincerely required overflowed with the fin de siecle phenomenon.

• Journal of the Korean Home Economics Association
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• v.28 no.2
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• pp.15-29
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• 1990

A survey was conducted of 1,454 customers to investigate dining out behaviors at fast food restaurants of Youido department compound, Myung-dong and Gang-nam district in Seoul, in April, 1988. The results are summarized as follows; The majority, 85% of customers, were aged 14 to 30, consisting of junior and senior high school children, college students and company employees. The reasons given by customers for patronizing fast food restaurants were the following, from most to least frequent; "convenient to dining," "the adequate place for the companionship", "the surroundings and dining equipment are pleasant and hygienic", "to be able to stay as long as I want". The fast foods purchased by the customers were mostly for a between meal snack or ice cream or drink rather than a full meal. The majority of the customers ate the purchased foods at the fast food restaurnats. However, a limited number of female customers preferred to take the packed fast foods to their homes. Tast Preference was a major factor in food selection from available food items. Ice cream, juice, French fried potatoes, salad, fried chicken, rolled rice with laver, and coke were high on the list of liked foods; in constrast, lower preference was for porridge, fish burger, doughnut, chicken burger and rice cake. Preference by food nationality was highest for Korean food, then Western food, Chinese food, Italian food and Japanse food, in that order. Customers offered suggestions for better fast food service, such as lowering the price, greater variety in the menu, increasing the propotion of vegetables and fruits on the fast food menu adn developing fast foods from traditional Korean foods. The customers, in particular, emphasized a need for the development of Korean traditional beverage of malted drink and persimmon punch, as well as mungbean pan cakes and sweet-spicy rice noodles(docbokki), as fast foods.y rice noodles(docbokki), as fast foods.

• Tunnel and Underground Space
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• v.13 no.2
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• pp.100-107
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• 2003

Deformation is found by an external force in the rock which has internal stress. So, deformation is increased in time what is stressed under constant load. Rock materials collapse suddenly in a long period when the creep rate increases slightly. So mechanical deformability of the ground is an essential condition for determination of long term safety in structures. The result of analysis in 40%, 50%, 60%, 70% of constant load in creep test, strain velocity constants $\alpha$ and ${\gamma}$ increase with load increasement. Griggs equation is more exact than Li and Xia, Singh equation, and G$_2$of a flow constant by Burger's model decreases with stress increasement, but η$_1$,η$_2$and G$_1$ manifest irregularly in this study.