• Proceedings of the Korean Society of Propulsion Engineers Conference
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• v.y2005m4
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• pp.83-87
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• 2005

In this paper, the combustion characteristics of a hybrid propulsion system were studied with various L/D(length vs diameter) ratio of the single port type solid fuel. Experiments of L/D ratio change were performed for 2 cases with the fixed grain port diameter and fuel length respectively. For the First case, results show that there are no large variation for regression rates as the L/D ratio changes. And as the L/D ratio increases, the O/F ratio and thrust tends to increase. For the Second case, there are no large change for O/F ratio and thrust as L/D ratio changes. On the other hand, as the L/D ratio decreases, only the regression rate tends to increase.

• Journal of the Korean Society of Propulsion Engineers
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• v.9 no.4
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• pp.31-38
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• 2005

In this paper, the combustion characteristics of a hybrid propulsion system were studied with various L/D(length vs diameter) ratio of the single po.1 type solid fuel. Experiments were performed for 2 cases with the fixed grain port diameter and fuel length respectively. For the first case, results show that there are no large variations for regression rates as the L/D ratio changes. And as the L/D ratio increases, the O/F ratio decreases and thrust, characteristic velocity tends to increase. For the second case, there is no large change for O/F ratio, thrust and characteristic velocity as L/D ratio changes. On the other hand, as the L/D ratio decreases, only the regression rate tends to increase. Experimentally, exponent n in $\dot{r}=a{G_0}^n$ was found about 0.5 and then the O/F ratio was shown nearly constant. In the experiment, PE and gas oxygen were used as a fuel and an oxidizer.

• Korean Journal of Food Science and Technology
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• v.42 no.2
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• pp.204-209
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• 2010

This study was conducted to investigate the anti-diabetic activity of Kocat-D1, which is widely used in traditional medicine to treat diabetes in Shandong, China. Sprague Dawley rats (8 weeks of age) were separated into 4 groups: a normal control, streptozotocin (STZ)-induced diabetic rat group (DM control), Kocat-D1-1 (diabetic rat treated with 0.25 g/kg/day hot water extract), and Kocat-D1-2 (diabetic rat treated with 1 g/kg/day hot water extract). After eight weeks of treatment, the fasting blood glucose levels of the Kocat-D1-1 ($334.3{\pm}32.9\;mg/dL$) and Kocat-D1-2 group ($259.5{\pm}35.0\;mg/dL$) were significantly lower when compared to the DM control group ($451{\pm}42.6\;mg/dL$). Furthermore, the levels of glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT), albumin and high-density lipoprotein (HDL) cholesterol in the serum of the Kocat-D1-2 group were significantly normalized when compared to the DM control group. However, significant differences were not observed between the Kocat-D1-1 group and the DM control group. Histochemical staining of the liver of the Kocat-D1-2 group revealed no fat accumulation. The insulin level was significantly upregulated in the Kocat-D1-2 group ($0.13{\pm}0.02\;ng/mL$) when compared to the DM control group ($0.05{\pm}0.04\;ng/mL$). The relative volume of $\beta$-cells in the pancreas of the Kocat-D1-2 group ($49.4{\pm}4.2%$) also increased significantly when compared to the DM control group ($12.9{\pm}7.9%$). These results suggest that Kocat-D1 exerts an anti-hyperglycemic effect through the enhancement of insulin secretion.

• Solar Energy
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• v.11 no.2
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• pp.63-69
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• 1991

A Steady laminar natural convection heat transfer from two isothermal square beams attached to a vertical adiabatic plate has been studied numerically. The results have been obtained for dimensionless beam spacings, $0.5{\le}D/L{\le}3.0$, and for Gr=5000-10000 at ${\phi}_2/{\phi}_1=1.0$. 1. The local Nusselt number from the beam surface is increased with the dimension-less beam spacing D/L. but that of the downward surface of the lower beam is almost same as the D/L increases. And, the local Nusselt number from the upward surface of a lower beam is greatly increased with D/L. 2. The beam spacings of the maximum mean Nusselt number for the downward surface of an upper beam and the upward surface of a lower beam occur at. D/L =2.6 and 2.0 respectively. 3. The beam spacing for the maximum total mean Nusselt number occurs at D/L = 2.6.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.520-522
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• 1991

The ranges of D(-)- and L(+)-lactic acids contents in commercial liquid yogurt were $6.1{\sim}535.8mg/100ml\;and\;70.0{\sim}664.6mg/100ml$, respectively. The ratio of L(+)-lactic acid to D(-)-lactic acid was $0.2{\sim}109.0$. The ranges of D(-)- and L(+)-lactic acids contents in commercial semi-solid yogurt were $10.1{\sim}418.3mg/100g\;and\;515.8{\sim}792.1mg/100g$ respectively. The ratio of L(+)-lactic acid to D(-)-lactic acid was $1.2{\sim}78.4$.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.10 no.2
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• pp.179-184
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• 2007

Purpose: Obesity has recently emerged as a significant health problem in the pediatric population, and the prevalence of non-alcoholic fatty liver disease is increasing in tandem with a significant rise in childhood obesity. Therefore, this study was conducted to clarify the risk factors of non-alcoholic steatohepatitis in obese children. Methods: We enrolled 84 obese children who visited the pediatric obesity clinic at Yeung-Nam university hospital. The patients were divided into two groups based on their alanine aminotransferase (ALT) level (separated at 40 IU/L), and the mean of ages, total cholesterol levels, HDL-cholesterol levels, LDL-cholesterol levels, triglyceride (TG) levels, as well as the mean obesity index, and body fat percentage of the two groups were then compared. Results: When the mean of ages ($10.5{\pm}1.6$ vs. $10.7{\pm}2.0$ years), total cholesterol levels ($183.0{\pm}29.1$ vs. $183.7{\pm}31.3$ mg/dL), HDL-cholesterol levels ($53.0{\pm}10.2$ vs. $55.7{\pm}13.0$ mg/dL), LDL-cholesterol levels ($113.4{\pm}30.2$ vs. $113.0{\pm}30.0$ mg/dL), triglyceride levels ($99.4{\pm}62.9$ vs. $114.2{\pm}47.3$ mg/dL), obesity indexes ($44.7{\pm}12.2$ vs. $47.9{\pm}15.1%$), and body fat percentages ($32.7{\pm}5.0$ vs. $34.0{\pm}4.8%$) of group 1 (ALT${\leq}$40 IU/L) were compared with those of group 2 (ALT${\geq}$41 IU/L), no significant differences were observed (p>0.05). However, hypertriglyceridemia (TG${\geq}$110 mg/dL) was more frequent in group 2 than in group 1 (p=0.023). Conclusion: TG may be an important risk factor in non-alcoholic steatohepatitis and further study regarding the risk factors in non-alcoholic steatohepatitis is required.

• Journal of Chest Surgery
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• v.37 no.9
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• pp.781-786
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• 2004

None of the currently available strategies for diagnosis and management of the pleural effusion are ideal. We tried to evaluate the validity of VEGF in differential diagnosis of the pleural effusion and find out if VEGF were correlated with the established markers. Material and Method: 35 patients with pleural effusion were divided into malignant effusion (n=10), benign effusion (n=5), infectious effusion (n=10), and pneumothorax (n=10), respectively. The pleural fluids from each group were examined for differential cell count, chemistry (glucose, protein, LDH, and ADA), and VEGF. Result: Glucose level was lower in infectious effusion compared with benign effusion (60.5$\pm$36.09 mg/dL vs. 162.0$\pm$19.80 mg/dL, p=0.011). ADA level in infectious effusion was higher compared with malignant effusion (87.9$\pm$42.62 IU/L vs. 27.7$\pm$31.04 IU/L, p=0.024). Malignant effusion (p=0.026) and infectious effusion (p=0.048) showed significantly higher level of VEGF than that of pneumothorax. VEGF level was substantially higher in malignant effusion compared with benign effusion (364.38$\pm$433.83 pg/dL vs. 53.3$\pm$22.20 pg/dL, p=NS). The pleural VEGF level did not correlate with the other markers. Conclusion: The measuring pleural VEGF may be helpful in diagnosing malignant and infectious pleural effusion that increase angiogenesis and vascular permeability, but it can not discriminate between the two. The pleural VEGF may not be correlated with the established markers. The measurement of pleural VEGF might discriminate between malignant and benign effusion.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.9
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• pp.1148-1160
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• 2007

This study was performed to document the association between eating behaviors and major risk factors for cardiovascular diseases. Those who stated that they ate a daily breakfast for male and female were 88.6% and 96.0%, $1{\sim}2$ times a week were 9.1% and 2.0%, $3{\sim}4$ times a week were 2.3% and 2.0%, respectively. Those who stated that they were overeating of $0{\sim}1$ time a week for man and female were 80.7% and 89.9%, overeating of $2{\sim}3$ times a week were 19.3% and 10.1%, respectively. Those who said that they were regular of meal time for man and female were 38.6%, and 37.4%, sometimes irregular of meal time were 14.8% and 19.2%, irregular of meal time were 46.6% and 43.4%, respectively. Those who said that they were light of eating volume for man and female were 20.5% and 25.3%, moderate of eating volume were 69.3% and 61.6%, heavy of eating volume were 10.2% and 13.1%, respectively. Those who said that they were very fast of eating speed for man and female were 15.9% and 8.1%, fast of eating speed were 51.1% and 34.3%, moderate of eating speed were 4.5% and 20.2%, slow of eating speed were 17.0% and 14.1%, and very slow of eating speed were 11.4% and 23.2%, respectively. Higher frequency of breakfast a week resulted in higher serum total cholesterol and blood sugar for the daily eating group for both genders with women having high LDL-cholesterol and HDL-cholesterol. Both group had high HDL-cholesterol and low blood sugar with less number of overeating, with men having low triglyceride and LDL-cholesterol. With regular meal, both group had low triglyceride, total-cholesterol, atherogenic index, and blood sugar with women having low LDL-cholesterol. For both groups, the triglyceride, total-cholesterol, LDL-cholesterol, atherogenic index, and blood sugar had higher figures for overeating, with men having low HDL-cholesterol and women having high HDL-cholesterol. This study revealed that less number of overeating, regular mealtime, and less volume of food intake are effective in preventing and treating for the cardiovascular diseases.

• Journal of the Korean Society of Food Culture
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• v.17 no.1
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• pp.30-36
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• 2002

The effects of Bamboo(Pseudosasa japonica Maki) extracts on serum lipid concentrations were evaluated in rats. Ninety-eight male Sprague-Dawley rats weighing $100{\pm}10g$ were divided into fourty groups and fed high fat diets for four weeks. Experimental groups were administered with following diets; basal fat diet(control), basal and high fat diets with 1% cholesterol and Bamboo(Pseudosasa japonica Maki, -1%, -3%, -5%) extracts. The concentrations of serum triglyceride in rats fed the Bamboo(Pseudosasa japonica Maki) extract, high fat, 1% cholesterol, and Pseudosasa japonica Maki, -1%, -3%, -5% were lower than those in other groups. The concentrations of total cholesterol in the Pseudosasa japonica Maki, -1%, -3%, -5% groups were lower than those in fat diet groups. The concentrations of HDL-cholesterol in serum of the Pseudosasa japonica Maki, -1%, -3%, -5% groups were significantly higer than those of other groups. The levels of LDL-cholesterol in serum of the Pseudosasa japonica Maki, -1%, -3%, -5% groups were tended to be lower than those of other groups. These results suggest that Bamboo(Pseudosasa japonica Maki) extract may reduce elevated levels of serum lipid concentrations in rats fed high fat diets.

• Journal of Korea Entertainment Industry Association
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• v.13 no.5
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• pp.139-143
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• 2019

The aim of this study was to assess the association of vitamin D and urine microalbumin/creatinine (uACR) and obesity. The study subjects were Korean adults 20 years or older (n = 4,948) who participated in the Korea National Health and Nutrition Examination Survey 2012. Analysis of covariance test adjusted for covariates were performed for uACR levels in relation to vitamin D status [vitamin D deficient, 25(OH)D < 10 ng/dL; vitamin D insufficient, 25(OH)D ≥ 10, < 20 ng/dL; vitamin D sufficient, 25(OH)D ≥ 20 ng/dL]. The key study results were as follows: First, in the populations without obesity (BMI < 25 kg/m²), uACR levels were decreased with the increasing of vitamin D status (p < 0.001) after adjusting for relevant variables. Second, in the populations with obesity (BMI ≥ 25 kg/m²), the association between uACR levels and vitamin D status was not significant (p = 0.659). In conclusion, urine microalbumin/creatinine levels were inversely associated with vitamin D status in Korean adults without obesity, but not in Korean adults with obesity.