• Journal of Korean Society of Steel Construction
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• v.19 no.3
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• pp.259-270
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• 2007

This paper presents an analytical method of evaluating the flexural behavior of RC (reinforced concrete) beams strengthened with high-strengh bars. The former experimental results were used to compare with the analytical results. The experimental results also outline the advantages of externally strengtheng method with high-strenght bars. To evaluate the flexural behavior of RC beams strenghtend with unbonded high-strength bars, this paper proposes a method involving a simple strength-summation method. This method basically assumes that the total strength of RC beams strengthened with high-strength bars is equal to the sum of the strengths of the RC beams and the high-strength bars. This analytical method also includes the effects of compressive force due to the tension from high-strength bars. A comparison of the analytical and experimental results leads to the conclusion that the simple strength-summation mothod can simulate the flexural behavior of RC beams strengthened with high-strength bars with a good level of accuracy.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.1
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• pp.10-18
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• 2017

A total of nine Korean indigenous goats were used in a cross-over arrangement to give nine replicates per treatment, and they were housed individually assigned to 1 of 9 dietary treatments. Nine treatments were 0, 500, and 1000 ppm of quercetin supplementation in diets by mixing roughage and concentrate with different ratios (RC ratio) of 3:7 (RC 30), 5:5 (RC 50) and 7:3 (RC 70). Nutrient utilizations of dry matter, crude fat and NDF were not affected by neither RC ratio nor dietary quercetin (p>0.05), but the rate of crude protein and ADF increased in animals in RC 70 group regardless of quercetin supplementation (p<0.05). In addition, higher RC ratio increased (p<0.05) N retention and N retention rate. Total VFA, acetic acid, propionic acid, iso-butyric acid, butyric acid, iso-valeric acid and valeric acid contents were not affected (p>0.05) by dietary quercetin. Meanwhile, lower total cholesterol level exhibited in animals in RC 70 group compared to RC 30 or 50 groups, unrelated to dietary quercetin (p<0.05), however other plasma parameters were not influenced (p>0.05) by RC ratio and dietary quercetin. Our results indicated that both RC ratio and dietary quercetin may not directly affect the production indices and immune responses in Korean indigenous goat.

• Journal of Society of Preventive Korean Medicine
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• v.16 no.3
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• pp.155-165
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• 2012

Objective : The object of this study is to confirm the immune enhancement effect of Rubus coreanus Miquel (RC) (30% EtOH extract) on RAW264.7 mouse macrophage cell line. Methods : RAW264.7 cells were treated with $10-500{\mu}g/mL$ RC for 24 hours. Cell viability was then measured using WST assays. Levels of intracellular NO and ROS were measured by Griess reagent and DCFH-DA staining respectively. Levels of iNOS and COX-2 mRNA was determined by RT-PCR. Secretion levels of IL-$1{\beta}$ and IL-6 cytokines were evaluated by sandwich ELISA assay. Western blot analysis was performed to measure the levels of intracellular molecules related to MAPKs pathways. Results : RC suppressed the growth of RAW264.7 cells. RC increased the production of NO and ROS. RC increased the mRNA and protein levels of COX-2 and iNOS. RC augmented the levels of secreted IL-$1{\beta}$ and IL-6 cytokines. RC increased MAPKs phosphorylation. Conclusion : In summary, our result shows that RC has inflammatory effect increasing the levels of NO, ROS and secreted cytokines and activating MAPKs. Hence, RC seems to have an immune enhancement effect.

• Journal of Oriental Neuropsychiatry
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• v.32 no.3
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• pp.155-166
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• 2021

Objectives: To analyze correlation between CSEI-S and MMPI-2 subscales to provide evidence for clinical application of the CSEI-S. Methods: Survey data of CSEI-S and MMPI-2 from 109 university students were analyzed. Demographic characteristics were subjected to descriptive analysis. Mann-Whitney U test and Pearson's correlation analysis were performed for CSEI-S and MMPI-2 scores. Results: The CSEI-S scale Joy (喜) showed a negative correlation with MMPI-2 clinical scales Hs, D, Hy, Pd, Pa, Pt, Sc, and Si. Six negative emotion scales of the CSEI-S showed positive correlations with MMPI-2 clinical scales except Mf and Ma. The CSEI-S scale Joy (喜) showed negative correlations with MMPI-2 restructured clinical scales RCd, RC1, RC2, and RC7. Six negative emotion scales of the CSEI-S showed positive correlations with restructured MMPI-2 clinical scales. The 60T-and-over group of MMPI-2 clinical scales D, Pd, Pa, Pt, Sc, Si, and Si showed significantly higher negative emotions than other groups. The 60T-and-over group of MMPI-2 scales D, Pt, Sc, and Si showed significantly lower Joy (喜) score than other groups. The 60T-and-over group of MMPI-2 restructured clinical scales RCd, RC2, RC3, RC6, RC7, RC8, and RC9 showed significantly higher negative emotions than other groups. The 60T-and-over group of MMPI-2 scales RCd, RC6, and RC7 showed significantly lower Joy (喜) scores than others. Conclusions: The CSEI-S showed consistent results with the original CSEI and MMPI-2 subscales. Thus, is a useful diagnostic tool in clinical practice.

• Mass Spectrometry Letters
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• v.12 no.2
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• pp.53-58
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• 2021

Previous in vitro studies have demonstrated that ginsenoside Rc inhibits UGT1A9, but there are no available data to indicate that ginsenoside Rc inhibits UGT1A9 in vivo. The effect of single and repeated intravenous injection of ginsenoside Rc was evaluated on the pharmacokinetics of mycophenolic acid. After injection of ginsenoside Rc (5 mg/kg for one day or 3 mg/kg for five days), 2-mg mycophenolic acid was intravenously injected, and the pharmacokinetics of mycophenolic acid and mycophenolic acid-β-glucuronide were determined. Concentrations of mycophenolic acid and its metabolite from rat plasma were analyzed using a liquid chromatography-triple quadrupole mass spectrometry. Single or repeated pretreatment with ginsenoside Rc had no significant effects on the pharmacokinetics of mycophenolic acid (P > 0.05): The mean difference in maximum plasma concentration (C_max) and area under the concentration-time curve (AUC_inf) were within 0.83- and 0.62-fold, respectively, compared with those in the absence of the ginsenoside Rc. These results indicate that ginsenoside Rc has a negligible effect on the disposition of mycophenolic acid in vivo despite in vitro findings indicating that ginsenoside Rc is a selective UGT1A9 inhibitor. As a result, ginsenoside Rc has little possibility of interacting with drugs that are metabolized by UGT1A9, including mycophenolic acid.

• Computers and Concrete
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• v.14 no.6
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• pp.767-783
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• 2014

The use of composite materials to strengthen reinforced concrete (RC) structures against blast terror has great interests from engineering experts in structural retrofitting. The composite materials used in this study are rigid polyurethane foam (RPF) and aluminum foam (ALF). The aim of this study is to use the RPF and the ALF to strengthen the RC panels under blast load. The RC panel is considered to study the RPF and the ALF as structural retrofitting. Field blast test is conducted. The finite element analysis (FEA) is also used to model the RC panel under shock wave. The RC panel performance is studied based on detonating different TNT explosive charges. There is a good agreement between the results obtained by both the field blast test and the proposed numerical model. The composite materials improve the RC panel performance under the blast wave propagation.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.997-1002
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• 2001

Tensile strength of CFRP (Carbon Fiber Reinforced Polymer) is approximately 10 times higher than that steel reinforcement, but the design strength of CFRP is normally reduced by the bond failure between RC and CFRP. Many researches have been carried out, concerned with bond behavior between RC and CFRP to prevent the unpredicted bond failure of RC beam strengthened by CFRP, but the national design code for design bond strength of CFRP hasn't been constructed. In this study, 3 beams specimen strengthened by CFRP under the variable of bonded length were tested to derive the design bond strength of CFRP to the RC flexural members. Also 2 beams specimen strengthened by CFRP were tested to inspect the construction environment effects such as mixing error of epoxy resin and the amount of primer epoxy resin. From the test results, It is concluded that the maximum design bond strength of CFRP to RC flexural member is considered to be $\tau_{a}$=8kgf/$cm^{2}$.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.537-542
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• 1999

The design methodologies for carbon fiber sheet(CFS) strengthening of RC structures are not well established yet because the structural behavior of strengthened RC structures is more complex than that of unstrengthened ones. Even though the research for the methods using CFS has beed studied, the strengthening effects and structural behaviors of strengthened structures are not systematized yet. The purpose of this study is to carry out the experimental studies on three kinds of half scale RC slab bridges and to investigate the behavior of RC slab bridges from the experimental results. Typical flexural failure occurs in the non-strengthening slab like general RC slab bridges, and also the flexural failure occurs in the all area strengthened slab with sudden rip-off failure of strengthening material by punching shear. For the case of strip type strengthened slab, flexural failure occurs, with rip-off of second strip at the base of loading point. Strengthening effect on the slab using CFS is that the strength is increased upto 7~15 percent and the crack pattern is changed.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.470-473
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• 2006

Past experiences from recent earthquakes indicate that shear failures of beam-column connections were one of the main reasons causing significant damages and collapses of RC structures subjected to earthquake loadings. Many researchers and engineers have conducted to propose an effective way to improve the joint shear strength of RC connections. This paper presents an analytical model for the RC exterior beam-column joints strengthened with CFRP sheets. In the analytical model, the effect of shear behavior of the RC beam-column joint, bond slip of the beam longitudinal reinforcements and CFRP sheets were considered and incorporated into the non-linear structural analysis program. Final analytical results were compared with those from the experiment of eight exterior RC beam-column specimens. The analytical results showed that the developed connection model is very useful to investigate the hysteretic joint behavior and overall load-displacement response of the RC beam-column connections strengthened with CFRP sheets.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.106-109
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• 2006

It has been shown that many reinforced concrete(RC) structures designed without seismic details have experienced brittle shear failures in the beam-column joint area and may result in large permanent deformations and structural collapse. In this study, experimental investigations for RC beam-column joints strengthened with the carbon fiber-reinforced polymer(CFRP) under cyclic loadings were presented. The use of CFRP in the joint was varied to determine the effective way of improving the structural performances of RC joints. Ten RC beam-column joints were designed and tested with cyclic loadings. The experimental results showed that the use of CFRP in RC joints would be very effective solutions to improve the seismic performances of the non-seismic RC joints. All of the non-seismic design specimens strengthened with CFRP sheets showed the significant increase of strength and ductility.