• 대한예방의학회:학술대회논문집
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• 1994.02b
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• pp.158-163
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• 1994

Slightly elevated urinary albumin excretion rate (microalhuminuria) is a marker of early diabectic nephropathy, but it is unclear if the established definition of microalbuminuria ($20-200{\mu}g/min$) is correct for children and adolescents. We investigated th.: albumin excretion rate, albumin/creatinine ratio and urinary albumin concentration in 150 healthy schoolchildren and adolescents to (a) obtain a reterence value for albumin excretion rate, (b) relate albumin excretion to pubertal stages and (c) evaluate albumin/creatinine ratio and morning albumin concentration as screening methods for elevated albumin excretion rate. Albumin concentration was measured by immunoturbidimetry in timed overnight urine samples. The albumin excretion showed a skewed distribution (geometric mean $3.2{\mu}g/min$, 95 percentile ($15.1{\mu}g/min$). In girls. a peak in the albumin excretion rate was found at the pubertal stage 4 (Tanner) and in boys at stage 5. Albumin/creatinine ratio of 2.5 mg/mmol as a screening level for elevated albumin excretion ($15{\mu}g/min$) showed a high positive (0.88) and negative (0.99) predictive value.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.6
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• pp.142-154
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• 1998

The effects of recirculated exhaust gas on the characteristic of soot emissions have been investigated by using an eight-cylinder, four-stroke, direct injection and water-cooled diesel engine operating at several loads and speeds. The experiments in this study are carried out at the fixed fuel injection timing of $38^{\circ}$ BTDC regardless of experimental conditions. The intake oxygen concentration and the mean equivalence ratio calculated by the intake air flow and fuel consumption rate are used to analyze and discuss the influences of EGR rate on soot emissions. Results of this study indicate that soot emissions increase owing to the drop of intake oxygen concentration and the rise of equivalence ratio as the EGR rate increases at a given engine load and speed, especially the high load.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.199-204
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• 2001

This paper showed the study on the heat transfer into space by the aspect ratio of solar concentration absorber, and the purpose of this study is to obtain the optimum aspect ratio and tilt angle. The boundary conditions of a numerical model were assumed as follows : (1) The heat source is located at the center of absorber. (2) The bottom was is opened and adiabatic. (3) The top, right and left walls are cooled wall. The parameters for the study are the tilt angles and the aspect ratio. The velocity vectors and isotherms were dense at wall side and the heat source. The mean Nusselt number had a maximum value at Ar=1:1 and $\theta=0^{\circ}$ and showed a low value as the tilt angles were increased.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.3
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• pp.58-64
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• 1997

A micromechanics model to describe the elastic behavior of fiber or whisker reinforced metal matrix composites was developed and the stress concentrations between reinforcements were investigated using the modified shear lag model with the comparison of finite element analysis (FEA). The rationale is based on the replacement of the matrix between fiber ends with the fictitious fiber to maintain the compatibility of displacement and traction. It was found that the new model gives a good agreement with FEA results in the small fiber aspect ratio regime as well as that in the large fiber aspect ratio regime. By the calculation of the present model, stress concentration factor in the matrix and the composite elastic modulus were predicted accurately. Some important factors affecting stress concentrations, such as fiber volume fraction, fiber aspect ratio, end gap size, and modulus ratio, were also discussed.

• Journal of Power System Engineering
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• v.6 no.1
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• pp.43-49
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• 2002

This paper showed the study on the heat transfer into space by the aspect ratio of solar concentration absorber, and the purpose of this study was to obtain the optimum aspect ratio and tilt angle. The boundary conditions of a numerical model are assumed as follows : (1) The heat source is located at the center of absorber. (2) The bottom wall is opened and adiabatic. (3) The top, right and left walls are cooled wall. The parameters for the study are the tilt angles and the aspect ratio. The velocity vectors and isotherms were dense at wall side and the heat source. The mean Nusselt number had a maximum value at Ar=1:1 and ${\theta}=0^{\circ}$ and showed a low value as the tilt angles were increased.

• Journal of Energy Engineering
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• v.7 no.1
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• pp.7-16
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• 1998

Numerical computations were performed for the gasification of five different coals such as Lewis-Stockton bituminous, Utah bituminous. Illinois #6 bituminous, Usibelli sub-bituminous and Beulah-Zap lignite, to assess the effect of variation in oxygen to coal ratio and steam to coal ratio on reactive flow fields within an axisymmetric, entrained-flow gasifier. The concentrations of major products, CO and $H_2$, were calculated with varying oxygen to coal ratio(0.7~1.4) and steam to coal ratio. To verify the validity of predictions, the predicted and the measured values of CO and $H_2$ concentrations at the exit of the gasifier were compared for Roto coal. Reasonable agreement was obtained between the predicted and measured values. Predictions showed that the (CO+H_2$) concentration increased gradually to its maximum value with increasing oxygen-coal ratio, and CO concentration decreased, but $H_2$ concentration increased to some extent with increasing steam-coal ratio. When the oxygen-coal ratio was between 1.0 and 1.2, and the steam-coal ratio was between 0.3 and 0.4, high values of the cold-gas efficiency were obtained.

• Journal of Korean Medicine Rehabilitation
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• v.20 no.3
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• pp.27-35
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• 2010

Objectives : The present study investigated anti-inflammatory effect of Artemisia Capilaris Thunberg in lipopolysaccharide-exposed rats. Methods : We divided lipopolysaccharide-exposed Sprague-Dawley rats into 4 groups. They were normal group, feed with 100 mg/kg Artemisia Capillaris Thunberg group, feed with 200 mg/kg Artemisia Capillaris Thunberg group and feed with 300 mg/kg Artemisia capilaris Thunberg group. They were administered for 6 weeks. We measured counts of red blood cell(RBC), the values of hemoglobin(Hb) and packed cell volume(PCV), plasma total protein concentration, albumin concentration, the ratio of albumin/globulin, the activities of plasma glutamic oxaloacetic transaminase(GOT), glutamic pyruvic transaminase(GPT), lactate dehydrogenase(LDH), the counts of white blood cell(WBC), the ratio of neutrophils, lymphocytes, monocytes, basophils, eosinophils, the concentration of plasma interleukin-$1{\beta}$($IL-1{\beta}$), plasma interleukin-6(IL-6), plasma tumor necrosis factor-$\alpha$($TNF-{\alpha}$), plasma interleukin-10(IL-10), the concentration of liver $IL-1{\beta}$ and IL-6, $TNF-{\alpha}$, IL-10. Results : Counts of RBC and the values of Hb and PCV, plasma total protein concentration and albumin concentration, the activities of plasma GOT, GPT and LDH showed no significant difference in the treatment groups. and the ratio of albumin/globulin was increased in Artemisia Capillaris Thunberg groups. The counts of WBC showed lower values in Artemisia Capillaris Thunberg groups than those of control group, In the ratio of neutrophils Thunberg groups. The ration of monocytes, basophils and eosinophils were below 5%, and showed no characteristic trend. The concentration of plasma interleukin-$1{\beta}$($IL-1{\beta}$), plasma inerleukin-6(IL-6) and plasma tumor necrosis factor-$\alpha$($TNF-{\alpha}$) showed a lower values in the Artemisia Capillaris Thunberg groups than those of control group, and the concentration of plasma interleukin-10(IL-10) showed no significant difference in the treatment groups. The concentration of liver $IL-1{\beta}$ and IL-6 showed a lower values in the Artemisia Capillaris Thunberg groups than those of control group, however the concentration of liver $TNF-{\alpha}$ and IL-10 showed no significant difference in the treatment groups. Conclusions : The Artemisia Capillaris Thunberg groups gives positive results of anti-inflammatory response by lipopolysaccharide(LPS) derivation.

• KSBB Journal
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• v.19 no.5
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• pp.358-362
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• 2004

Characteristics of cell growth and poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] synthesis was investigated through flask and batch cultures of Alcaligenes latus and Comamonas acidovorans. The specific growth rate of C. acidovorans increased with yeast extract concentration and decreased with 1,4-butanediol concentration. Optimum glucose concentration for growth of C. acidovorans was 20 g/L. In one-step flask cultures of C. acidovorans, final dry cell weight and PHA content decreased with the ratio of 1,4-butanediol to glucose, while the 4HB fraction in copolymers gradually increased to 100 $mol\%$ with an initial 1,4-butanediol concentration of 20 g/L as single carbon source. The specific growth rate of A. latus decreased with v-butyrolactone concentration and optimum sucrose concentration for growth was 10 g/L. In batch cultures of A. latus, 4HB fraction increased with initial v-butyrolactone concentration. P(3HB-co-4HB) with 19 $mol\%$ 4HB was obtained when the initial ratio of v-butyloractone (g/L) to sucrose (g/L) was 10 : 10.

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.2
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• pp.247-256
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• 1986

An experimental investigation was conducted to study natural convection due to temperature and concentration differences between the two opposite end walls of a rectangular enclosure of aspect ratio 0.2. Flow motion in the enclosure appears as a uni-cell flow pattern for the relatively lower concentration and higher temperature differences and vice versa, while it appears as a multicell flow pattern for the comparable temperature and concentration differences. In the multi-cell flow regime, when the cellular flow motiion is very slow, vertical temperature differences within the cells are negligible while the vertical concentration differences are large. In addition, both the temperature and concentration differences are negligible across the interface between the slowly moving cells. For the fast moving cellular flow motion, on thel contrary, vertical temperature differences within the cells are large while the vertical concentration differences are negligible. In this case, temperature differences are negligible and the concentration differences are large across the interface between the fase moving cells.

• The Korean Journal of Physiology
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• v.10 no.1
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• pp.25-34
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• 1976

The action of serotonin on the sodium plus potassium activated ATPase activity in the rabbit red cell membrane has been investigated. The experiments were also designed to determine the mechanism of action of serotonin on the ATPase activity. The following results were obtained. 1) The NaK ATPase activity of rabbit red cell ghosts is stimulated by low concentration of serotonin but inhibited by higher concentration, and the concentration of serotonin for maximal activity is about 2mM. The pH optimum for the serotonin sensitive component is 8.0. 2) The activating effect of serotonin on the ATPase, with a given concentration of sodium in the medium, is increased by raising the potassium concentration but the ratio of activity is decreased. 3) The activating effect of serotonin on the ATPase, with a given concentration of potassium in the medium, is increased by raising the sodium concentration but the ratio of activity is decreased. 4) The ATPase activity is increased by small amounts of calcium but inhibited by larger amounts and the ratio of activity by serotonin is decreased by small amounts of calcium but increased by larger amounts. 5) The action of serotonin on the ATPase activity was not related to the amino group of lysine, the hydroxyl group of threonine, the carboxyl group of aspartic acid, or the imidazole group of histidine. 6) The action of serotonin on the ATPase activity is due to sulfhydryl group of the enzyme of NaK ATPase.