• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6A
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• pp.765-778
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• 2008

Performance Profiles are essential to predict the performance variation over time for the bridge management system (BMS) based on risk management. In general, condition profiles based on experts opinion and/or visual inspection records have been used widely because obtaining profiles based on real performance is not easy. However, those condition profiles usually don't give a good consistency to the safety of bridges, causing practical problems for the effective bridge management. The accuracy of performance evaluation is directly related to the accuracy of BMS. The reliability of the evaluation is important to produce the optimal solution for distributing maintenance budget reasonably. However, conventional methods of bridge assessment are not suitable for a more sophisticated decision making procedure. In this study, a method to compute quantitative performance profiles has been proposed to overcome the limitations of those conventional models. In Bridge Management Systems, the main role of performance profiles is to compute and predict the performance of bridges subject to lifetime activities with uncertainty. Therefore, the computation time for obtaining an optimal maintenance scenario is closely related to the efficiency of the performance profile. In this study, the Response Surface Method (RSM) based on independent and important design variables is developed for the rapid computation. Steel box bridges have been investigated because the number of independent design variables can be reduced significantly due to the high dependency between design variables.

• Journal of the korean society of oceanography
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• v.32 no.2
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• pp.63-68
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• 1997

Stable isotope profiles with fine-scale resolution were constructed from the fossil mollusk shells, Mercernaria mercernaria, obtained from the late Pleistocene transgressive deposits of Gomez Pit, Virginia, USA. Incremental sampling were made along the axis of maximum growth to provide high-resolution ${\delta}^{18}$O and ${\delta}^{13}$C records. The ${\delta}^{18}$O shell profiles exhibit a series of pronounced cycles in the overall amplitude, corresponding to strong seasonal variations in temperature, which is apparently positive environmental variable. Contrasts between the patterns of ${\delta}^{18}$O and ${\delta}^{13}$C profiles reflect the relationship influencing the seasonal carbon cycling in the shallow marine environment. Positive anomalies of the ${\delta}^{13}$C values during the summer were observed to be out of phase with the ${\delta}^{18}$O profile. Such relatively heavier carbon source may be alternated due to seasonal methanogenesis during the summer. A hypothesized methane-based system may be operated in the shallow and marginal marine environment, resulting in a ${\delta}^{13}$C enriched bicarbonate pool, in which the heavier isotope seems to be incorporated to the shell carbonate.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.14 no.3
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• pp.222-231
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• 2002

The ADP is an advanced piece of oceanographic equipment that measures water speed and direction profiles from the acoustic Doppler principle. In recent years, the strength of the acoustic backscatter obtained from ADP has been used to measure vertically suspended sediment concentration(SSC) profiles. In this study, an ADP was installed in coastal waters near Yumsan, on the west coast of Korea, and flow and sediment data were gathered simultaneously. SSC concentrations were calculated from the acoustic backscatter strengths adjusted by using calibrated acoustic coefficients. The observed SSC profiles were compared with analytical solutions and showed good agreement. Simultaneously, the suspended material fluxes were analyzed in detail. ADP was very useful for measuring the vertically distributed suspended sediment concentrations and flow velocity profiles.

• Journal of the Korean Society of Propulsion Engineers
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• v.2 no.2
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• pp.30-37
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• 1998

This paper investigates the linear stability of wakes with special emphasis on the effect of chemical reaction. Velocity and density profiles for laminar flows are obtained from analytic profiles as well as from simulation. Wakes have two generalized inflection points and two unstable modes-sinuous and varicose modes. For analytical laminar profiles, sinuous modes are more unstable than varicose modes irrespective of density variation, which shows wakes will be destabilized by sinuous modes. Large velocity difference and density difference lead to more unstable wakes due to large momentum difference. For simulated laminar profiles, chemical reaction with stoichiometric chemistry increases temperature and stabilizes the flow due to increase in compressible reacting wades, flow becomes stable as velocity increases due to viscous dissipation.

• Proceedings of the Korean Society of Food Science and Nutrition Conference
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• 2004.11a
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• pp.73-79
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• 2004

The large-scale preparation method for black soybean peptide (BSP; about 70% less than 10,000 Da; highly enriched with glutamic acid, aspartic acid, and arginine) was developed, and its effect on weight reduction and lipid profiles in rats was investigated. Sprague-Dawleymale rats were assigned to four dietary groups (high-fat diets containing 0, 2, 6, and 10% BSP) and fed four weeks to examine the effects of BSP. During the experiment, food intake was measured every two days and body weight was monitored two times a week. After the supplementation of BSP, liver and adipose tissues (epididymal, retroperitoneal and perirenal adipose tissue) in the rats were weighted and the lipid profiles in serum, liver, and feces were analyzed. At the results of body weight gain, liver and epididymal adipose tissue weight, BSP groups were more decreased than HF group (0% BSP), with greater decreases at higher BSP levels. The same patterns were shown in lipid profiles of serum, as BSP was increased, triglyceride and total cholesterol concentration decreased. The serum HDL-cholesterol level was increased with increasing at BSP levels. Total cholesterol concentration of liver and feces were decreased and increased, respectively, as BSP increased. The results confirm that BSP is involved in reducing the body weight and the improvement of lipid composition in serum and liver of rats and that BSP can be applied in weight reduction in the food products industry.

• The KSFM Journal of Fluid Machinery
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• v.5 no.4 s.17
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• pp.54-60
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• 2002

Experimental study was conducted to obtain the air velocity profiles in turbulent pipe flow. The acrylic smooth pipe (${\phi}=80mm$) was used for the test section of the flow loop. It was known that the velocity profiles of turbulent flow were different with Reynolds numbers and the viscous sublayer was usually quite thin. The following conclusions were drawn from the experimental investigations. Maximum velocity of the pipe center and flow-rate are useful for the duct design on the spot. The velocity profiles of high Reynolds number was flatter than those of low Reynolds number. It was known that the exponent, n, for power-law velocity profiles was $6{\sim}9$ depending on Reynolds number ranging from $10^4$ to $10^5$ in the turbulent flow, However, in this experiment study, it was $9{\sim}14$ depending on Reynolds number ranging from 17,000 to 123,727 in the turbulent flow, and $1.7{\sim}3.5$ depending on Reynolds number ranging from 2,442 to 4,564 in the transition region.

• International Journal of Vascular Biomedical Engineering
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• v.1 no.1
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• pp.24-31
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• 2003

As endothelial cells are subject to flow shear stress, it is important to determine the detailed velocity distribution in microvessels in the study of mechanical interactions between blood and endothelium. This paper describes a velocity field of the arteriole in the rat mesentery using an intravital microscope and high-speed digital video system obtained by a highly accurate PIV technique. Red blood cells (RBCs) velocity distributions with spatial resolutions of $0.8{\times}0.8{\mu}m$ were obtained even near the wall in the center plane of the arteriole. By making ensemble-averaged time-series of velocity distributions, velocity profiles over different cross-sections were calculated for comparison. The shear rate at the vascular wall also evaluated on the basis of the ensemble-averaged profiles. It was shown that the velocity profiles were blunt in the center region of the vessel cross-section while they were steep in the near wall region. The wall shear rates were significantly small, compared with those estimated from the Poiseuille profiles.

• Journal of Nutrition and Health
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• v.36 no.7
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• pp.667-674
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• 2003

The study was performed to investigate the effects of isoflavone and/or grape seed oil supplementation on serum and liver lipid profiles and bone strength in ovariectomized female rats. Female Spraque-Dawley rats were assigned into 4 groups of ovariectomized (O), isoflavone (0.085 mg/100 g b.w/day) in ovariectomized rats, grape seed oil in ovariectomized rats and isoflavone and/or grape seed oil in ovariectomized rats. After 8 weeks, biochemical profiles of serum, liver and bone were analyzed. Total food intakes, body weight gains and FER (food efficiency ratio) were not statistically significantly different among groups. Total cholesterol, triglyceride and LDL-cholesterol levels in serum were decreased by fed of isoflavone and/or grape seed oils. However, crude lipid and total cholesterol contents in liver were not affect of isoflavone and/or grape seed oil. The hepatic glutathione contents were increased by isoflavone and/or grape seed oil fed. The hepatic glutathione-S-transferase activity in isoflavone and/or grape seed oil supplemented groups were higher than that O group. Bone (scapular and femur bone) dry weight, femur of max weight and bending strength were no significant difference among groups. Our finding suggest that isoflavone/grape seed oils might have potential role for serum lipid profiles improvement and bone strength in vivo.

• Nutrition Research and Practice
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• v.1 no.2
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• pp.84-88
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• 2007

The purpose of this study was to identify dietary patterns among children and adolescents in Korea and to examine their associations with obesity and some blood profiles. One day food consumption data measured by 24-hour recalls on 2704 subjects aged 1 to 19 were used from 2001 Korea National Health and Nutrition Survey. The data of blood profiles available in the ages of 10 or older was also used. After categorizing each food consumed into 29 food or food groups, five dietary patterns were derived through a factor analysis and subjects were classified into three major dietary patterns via a cluster analysis using the factor scores. Three dietary patterns were identified as 'traditional diet' (25.6%), 'westernized-fast food' (6.2%), and 'mixed diet' (68.2%). The 'traditional diet' pattern had a higher percentage in boys. Both the 'traditional diet' and the 'westernized-fast food' had higher proportions of adolescents (12-19 y) than younger children, while the 'mixed diet' had a higher percentage of preschool children (1-5 y). Obesity rate analyzed within each age group showed no differences among 3 dietary pattern clusters. Blood pressure and all plasma profiles were not different among dietary patterns when adjusted with age and gender. Conclusively, children and adolescents in Korea had three distinct dietary patterns, which were associated with gender and age. These patterns could be useful to plan nutrition interventions for teenager health promotion.

• Journal of Nutrition and Health
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• v.38 no.9
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• pp.698-705
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• 2005

The purpose of this research was to investigate the effect of the boron supplementation on lipid profiles and antioxidant capacities in ovariectomized (OVX) rats. Rats were divided into 3 groups and fed diet with intake levels of boron (0.5 ppm,50 ppm,100 ppm) for 4 weeks. The half of rats in each group was ovariectomized and the others were sham-operated. And rats were fed same diets for 8 weeks after operation. Feed intake and weight gain were significantly increased by increasing boron intake and higher in OVX group than those in sham-operated. FER was significantly higher in OVX group than that of sham-operated. There were no significant differences in serum lipid profiles among the groups. The contents of hepatic total lipid were significantly higher in OVX group than those of sham-operated and the lowest in high-boron group. Hepatic GST activity was significantly decreased by ovariectomy and the lowest in very high-boron group. Hepatic catalase activity was the lowest in high-boron group of OVX. Hepatic TBARS level of high-boron group was the lowest in sham-operated groups. Hepatic TBARS level induced by AAPH was significantly decreased by increasement of boron supplementation. Taken together, this results suggest that the boron supplementation have the potential role for improving lipid profiles and antioxidant capacities in OVX rats.