• 한국식품영양학회지
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• 제10권1호
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• pp.110-116
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• 1997

여과제균한 배추즙에 김치에서 분리한 7주의 젖산균을 단독 접종하고 1$0^{\circ}C$, 2$0^{\circ}C$, 3$0^{\circ}C$ 및 4$0^{\circ}C$에서 배양하면서 각각의 증식곡선을 작성하고, 이를 이용하여 각 배양온도에서의 유도시간과 세대시간을 구하였다. 3$0^{\circ}C$에서 배양할 때의 유도시간은 Leu. mesenteroides subsp. dextranicum은 168분, Leu. mesenteroides subsp. mesenteroides는 204분, Leu. paramesenteroides는 612분, Lac. bavaricus는 258분, Lac. homohiochii는 228분, Lac. plantarum은 270분 그리고 Lac. brevis는 264분이었고, 세대시간은 Leu. mesenteroides subsp. dextranicum 및 Leu. mesenteroides subsp. mesenteroides는 36분, Lac. bavaricus는 33분, Lac. homohiochii는 39분, Lac. plantarum은 66분, Lac. brevis는 42분 그리고 Leu. paramesenteroides는 162분이었다. 배양온도를 3$0^{\circ}C$에서 1$0^{\circ}C$로 낮출 때 모든 균주들의 유도시간과 세대시간이 크게 연장되었는데, 이러한 연장은 Lac. plantarum에서 더욱 현저하게 나타났다. 1$0^{\circ}C$, 2$0^{\circ}C$ 및 3$0^{\circ}C$에서는 Leu. mesenteroides subsp. mesenteroides의 유도시간과 세대시간이 Lac. plantarum의 그것보다 더 짧았다. 그러나 4$0^{\circ}C$에서는 이러한 양상이 완전히 전도되었다. 전반적으로 보아 배양온도가 낮아질수록 Leu. mesenteroides subsp. mesenteroides의 증식에 상대적으로 더 유리하였고, 배양온도가 높아질수록 Lac. plantarum의 증식에 상대적으로 더 유리하였다.

• 한국식품과학회지
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• 제34권2호
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• pp.339-342
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• 2002

찰흑미와 일반찰벼 쌀알의 물리적 특성을 비교한 결과 무게와 길이, 길이와 폭의 비율, 부피는 찰흑미가 더 높았으나 폭과 밀도는 두 시료 모두 비슷하였다. 찰흑미와 일반찰벼 쌀알을 침지온도($20{\sim}50^{\circ}C$)에서 40분 동안 침지하면서 일정시간별로 꺼내어 수분흡수량을 조사한 결과 40분까지 계속적인 증가를 보였으며, 수분흡수속도상수($k_0$)는 침지온도가 증가할수록 수분흡수속도상수($k_O$)는 찰흑미와 일반찰벼 모두 증가하였는데 $20^{\circ}C$에서는 찰흑미($0.0090\;min^{-1/2}$)와 일반찰벼($0.0108\;min^{-1/2}$)는 비슷하였으나 $50^{\circ}C$에서는 찰흑미($0.0252\;min^{-1/2}$)가 일반찰벼$(0.034\;min^{-1/2})$보다 더 낮게 나타났다. $4^{\circ}C$에서 침지한 두 시료의 수분흡수속도상수는 찰흑미가 $0.033\;min^{-1/2}$, 일반찰벼는 $0.058\;min^{-1/2}$으로 찰흑미가 약 2배 정도 더 느리게 수분을 흡수하였고, 쌀알의 경도감소속도($-k_h$) 또한 찰흑미($0.022\;min^{-1}$)가 일반찰벼($0.048\;min^{-1}$)보다 약 2배 정도 더 느리게 감소함을 볼 수 있었다.

• Journal of Animal Science and Technology
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• 제56권7호
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• pp.26.1-26.10
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• 2014

Background: Endocrine disruptors are exogenous substance, interfere with the endocrine system, and disrupt hormonal functions. However, the effect of endocrine disruptors in different species has not yet been elucidated. Therefore, we investigated the possible effects of $17{\beta}$-estradiol (E2), progesterone (P4), genistein (GEN) and 4-tert-octylphenol (OP), on capacitation and the acrosome reaction in bovine, mouse, and porcine spermatozoa. In this in vitro trial, spermatozoa were incubated with $0.001-100{\mu}M$ of each chemical either 15 or 30 min and then assessed capacitation status using chlortetracycline staining. Results: E2 significantly increased capacitation and the acrosome reaction after 30 min, while the acrosome reaction after 15 min incubation in mouse spermatozoa. Simultaneously, capacitation and the acrosome reaction were induced after 15 and 30 min incubation in porcine spermatozoa, respectively. Capacitation was increased in porcine spermatozoa after 15 min incubation at the lowest concentration, while the acrosome reaction was increased in mouse spermatozoa after 30 min (P < 0.05). E2 significantly increased the acrosome reaction in porcine spermatozoa, but only at the highest concentration examined (P < 0.05). P4 significantly increased the acrosome reaction in bovine and mouse spermatozoa treated for 15 min (P < 0.05). The same treatment significantly increased capacitation in porcine spermatozoa (P < 0.05). P4 significantly increased capacitation in mouse spermatozoa treated for 30 min (P < 0.05). GEN significantly increased the acrosome reaction in porcine spermatozoa treated for 15 and 30 min and in mouse spermatozoa treated for 30 min (P < 0.05). OP significantly increased the acrosome reaction in mouse spermatozoa after 15 min (P < 0.05). Besides, when spermatozoa were incubated for 30 min, capacitation and the acrosome reaction were higher than 15 min incubation in E2 or GEN. Furthermore, the responsiveness of bovine, mouse and porcine spermatozoa to each chemical differed. Conclusions: In conclusion, all chemicals studied effectively increased capacitation and the acrosome reaction in bovine, mouse, and porcine spermatozoa. Also we found that both E2 and P4 were more potent than environmental estrogens in altering sperm function. Porcine and mouse spermatozoa were more responsive than bovine spermatozoa.

• Restorative Dentistry and Endodontics
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• 제23권1호
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• pp.433-442
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• 1998

The purpose of this study was to observe the changes of acidity of resin cement(Time Line), glass ionomer cement(GC Fugi Lining LC), zinc phosphate cement(Fleck's zinc cement). zinc oxide eugenol cement(Sultan,Chemists.) in vivo and in vitro. Class I cavities with 3mm depth were prepared on the occlusal surfaces of 20 recently extracted human Mn. molar teeth and 20 human Mn. 3rd molar teeth in oral cavity. The prepared cavities were divided into 4 groups of each 5 teeth using the above 4 cavity liners. Each cement was mixed in accordance with manufacturer's direction at the room temperature of $23^{\circ}{\pm}5^{\circ}C$ and filled into the cavity in a width of 1 mm. The microelectrode of pH meter was inserted into the prepared cavity which was filled with mixed cement, and the acidity of cement was measured for 3 days from the beginning of cement mix in vitro and in vivo. The measured acidity was then statistically analyzed by ANOVA. The results were as follows. 1. In vitro, the pH of zinc oxide eugenol cement was statistically lower than that of the three other groups at 2min, 4min, 6min, 8min, 10min, 12min, 18min, 20min. (p<0.05). 2. The pH of zinc oxide eugenol cement in vivo was statistically higher than that in vitro at 16min,16min, 20min(p<0.05). 3. The pH of zinc phosphate cement in vivo was statistically higher than that in vitro at 4min, 20min(p<0.05). 4. In vitro and in vivo, there was no significant difference in the pH between the resin cement and the glass ionomer cement(p>0.05). 5. The initial acidity was not high, but almost neutral in all kinds of the cements.

• 동아시아식생활학회지
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• 제22권5호
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• pp.604-612
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• 2012

The quality characteristics of yackwa made with goami powder at different baking temperatures (150, 160, 170, 180) and baking times (15, 20, 25 min) and at different dipping temperatures (65 and $80^{\circ}C$) and dipping times (15 and 30 min) were evaluated. To determine the optimal temperature and time for yackwa containing goami powder, color values, preference color and pictures were determind. The baking temperatures were $150^{\circ}C$ for 25 min, $160^{\circ}C$ for 15 min and 20 min, and $170^{\circ}C$ for 15 min. The weight of yackwa was heavier at low dipping temperatures and long dipping times. L-values and b-values were the highest at short dipping times. Hardness, moisture and overall preference was the lowest at low dipping temperatures and long dipping times.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.312-315
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• 2003

This paper deals with robust control problems of linear systems with matched nonlinear uncertainties. In order to handle the uncertainties, a Lyapunov min-max control approach can usually be adopted. By the way, the min-max control input is required to be switched and provokes chattering phenomena which limit the practical implementation. The magnitude of switching control input which cause chattering is dependent on the size of uncertainties. In this paper, it is shown that the magnitude of the min-max control input can be made small using a well-known disturbance observer technique and only considers the disturbance observing errors. The chattering phenomena can be reduced as small as possible by selecting a high diturbance observer gain. The simulations show that the min-max control with a disturbance observer can reduce chattering phenomena much smaller and guarantee much better robust performance rather than the one without a disturbance observer.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2009년 춘계학술대회논문집
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• pp.269-276
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• 2009

The local preconditioning method has both robust convergence and accurate solutions by using local flow properties for parameters in the preconditioning matrix. Preconditioning methods have been very effective to low speed inviscid flows. In the viscous and turbulent flows, deterioration of convergence should be overcame on the high aspect ratio grids to get better convergence and accuracy. In the present study, the local time stepping and min-CFL/max-VNN definitions are applied to compare the results and we propose the method that switches between two methods. The min-CFL definition is applied for inviscid flow problems and the min-CFL/max-VNN definition is implemented to viscous and turbulent flow problems.

• 한국환경과학회지
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• 제12권12호
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• pp.1269-1276
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• 2003

In order to know the effect of atuoclaving on the heavy metal removal using chitosan, lead removal capacities and removal rates by various chitosans in aqueous solution were compared according to the various autoclaving time. The lead removal efficiencies and removal rates by the autoclaved chitosan were found to be on the order of 15 min(98％) ＞ 10 min(95％) ＞ 30 min(83％) ＞ 5 min(53％) ＞ 60 min(47％) ＞ 0 min(22％) chitosan. The molecular weight of chitosan was decreased by the increase of autoclaving time. Therefore, the heavy metal removal capacity was not well correlated to the molecular weight. Langmuir isotherm was well fitted to experimental results of equilibrium adsorption on chitosan. In order to examine the process of lead removal by the autoclaved chitosan, TEMs, SEMs and FT-IR analyses were used. The surface of autoclaved chitosan was much more porous and the lead removal was mainly occurred on the surface of chitosan. The structure of autoclaved chitosan was same as that of controlled chitosan.

• 한국관광식음료학회지:관광식음료경영연구
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• 제15권1호
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• pp.127-136
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• 2004

This study was conducted to investigate the changes in physico-chemical characteristics of beef tenderloin steak by oven roasting at different internal temperatures. 1. Cooking time required for the internal temperatures of 60, 70 and $80^{\circ}$ of steaks were 15min, 23min and 28min, respectively, and standing time of cooked beef steaks were 10.5min at $60^{\circ}$, 9.4min at $70^{\circ}$ and 8.5min at $80^{\circ}$, respectively. 2. Total losses and evaporation losses were larges in cooked steaks at $60^{\circ}$ and $70^{\circ}$ than that of $80^{\circ}$ cooking. Total losses were 14.5% by cooking at $60^{\circ}$, 23.3% at $0^{\circ}$ and 26.6% at $80^{\circ}$ respectively. As internal temperature of meat was increased, moisture and fats content was decreased and protein content of meat was not changed.

• 대한수학회보
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• 제50권2호
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• pp.431-440
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• 2013

Let ($M^3$, $g$) be a 3-dimensional closed Sasakian spin manifold. Let $S_{min}$ denote the minimum of the scalar curvature of ($M^3$, $g$). Let ${\lambda}^+_1$ > 0 be the first positive eigenvalue of the Dirac operator of ($M^3$, $g$). We proved in [13] that if ${\lambda}^+_1$ belongs to the interval ${\lambda}^+_1{\in}({\frac{1}{2}},\;{\frac{5}{2}})$, then ${\lambda}^+_1$ satisfies ${\lambda}^+_1{\geq}{\frac{S_{min}+6}{8}}$. In this paper, we remove the restriction "if ${\lambda}^+_1$ belongs to the interval ${\lambda}^+_1{\in}({\frac{1}{2}},\;{\frac{5}{2}})$" and prove $${\lambda}^+_1{\geq}\;\{\frac{S_{min}+6}{8}\;for\;-\frac{3}{2}&lt;S_{min}{\leq}30, \\{\frac{1+\sqrt{2S_{min}}+4}{2}}\;for\;S_{min}{\geq}30$$.