• Geotechnical Engineering
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• v.7 no.4
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• pp.89-98
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• 1991

This paper presents the three-dimensional stability analysis of the homogeneous, isotropic soil Slopes. Rotational slides are assumed with a cylindroid central part terminated with log-spiral curved ends. The ratio of threeiimensional minimum factor of safety to two 4imensional case is examined and factor of safety changes are showed for the ratio of cylinder length to slope height. On touch babes the following conclusions may be made 1. Factors of safety computed for 3-D geometry differ considerablely from ordir,arty 2-D factor of. safety. Sinoe Fn 1 Fa2 exceeds unity, threeiimensional effects tend to increase the factor of safety. 2. A,B LIU increase, the value of Fb3/ Fs2 decreases. 3. The ratio of Fr/Fs2 appears to be very sensitive to c and values.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.4
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• pp.410-418
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• 2004

The multiaxial fatigue test under in-phase and out-of$.$phase load were performed to study what degradation phenomenon affects fatigue life with virgin and 3600 hrs degraded materials. The various kind of fatigue data fur fatigue life prediction were acquired under pure axial and pure torsional load of fully reversal condition. The models which was investigated are: 1) the von Mises equivalent strain range, 2) the critical shear plane approach method of Fatemi-Socie(FS) parameter, 3) the modified Smith-Watson-Topper(SWT) parameter. The result showed that, fatigue life by material degradation are decreased and life prediction which was used the FS parameter is not conservative but the best result.

• The Journal of Internal Korean Medicine
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• v.28 no.2
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• pp.230-241
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• 2007

Objective : This study was intended to ascertain the protective effect of phenolic-rich fraction (PRF) from Fructus Schisandrae on SH-SY5Y cells. Methods : PRF was obtained from the 80% ethanol extract of Fructus Schisandrae by Sepabeads SP-850 column chromatography. The neuroprotective effect of the FS PRS was investigated due to the hydrogen peroxide $(H_2O_2)-induced$ apoptosis of cultured SH-SY5Y cells. Results : Cell viability assays revealed that pretreating SH-SY5Y cells with PRF (10-200 ${\mu}g/mL$) resulted in significant dose-dependent protection against $H_2O_2-induced$ cell death. The effect was assessed by flow cytometric analysis of DNA contents using propidium iodide (PI) staining. The population of apoptotic cells was increased by 32.89% in only $H_2O_2$ (150 ${\mu}M$)-treated environment, but it was reduced by pre-treatment of FS PRF (200 ${\mu}g/mL$) to 21.61%. $H_2O_2-induced$ caspase-3 activation and PARP cleavage were reduced in FS PRF pre-treated cells, and PRF led to an apparent suppressive effect on the oxidative stress induced by reactive oxygen species (ROS). Conculsion : This study showed that Fructus Schisandrae should be useful for the treatment prevention of neurodegenerative diseases associated with elevated ROS levels.

• Aerospace Industry
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• v.48
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• pp.66-69
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• 1997

• Defense and Technology
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• no.5 s.231
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• pp.34-45
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• 1998

• Korean Journal of Applied Biomechanics
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• v.12 no.2
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• pp.279-293
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• 2002

In the study the subjects who 10 university golfers act, and the kinetic factors were analyzed by the ground reaction system. the conclusion are as follows. 1) In the golf putting swing, the ground reaction factors of sagital plane in aspect are showen that the left and right foot sufficient difference, in the level of p <.05. 2) In the golf putting swing, the ground reaction factors of frontal plane in aspect is showen that the left foot has no significant difference in AD BS in the level of p < .05. In success, IP, FS. It can show significant difference. In addition, the right foot is shown the success, There is significant difference. 3) In the golf putting swing, the ground reaction factors of the vertical plane in aspect are shown that the left foot has no significant difference in BS, FS in the level p < .05. In success, AD, IP. It can show significant difference. In addition, the right foot is shown the success, There is significant difference. 4) In the golf putting swing, the ground reaction factors of torque in aspect are shown that the left foot had no significant difference in BS in the level p < .05. In success, AD, IP, FS. It can show significant difference. In addition, the right foot has no significant difference in IP in the level p < .05. AD, BS, FS. There is significant difference. The summarized conclusions are as follows. The first that the power of sagital plane needs the motion which can get the good power change in the stabilized pose. The second is that the small motion can make good putting in stabilized pose. The third is that the body weight move to the direction of the ball. The fourth is that the putting which looks perfect oscillation is good motion.

• Journal of the Korea Concrete Institute
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• v.16 no.3 s.81
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• pp.407-414
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• 2004

The purpose of this study is to evaluate the ability to resist chloride ions penetration of the concrete structure under marine environment in south-east asia especially. In this study, high strength concrete(HSC) with various combination of ordinary portland cement(OPC), blast-furnace slag(SG) and silica fume(SF) are cured 23 and $35^{\circ}C$ considering the site weather, and are cured in water for 3, 7 or 56 days respectively. And to investigate the fundamental properties and the resistance of chloride penetration of various HSC, setting time, slump flow, compressive strength, void and ASTM C 1202 test were conducted. Test results show that the compressive strength of HSC is similar regardless of SG replacement ratio and total charge passed of chloride is the smallest at 40% replacement of SG. The compressive strength of G4FS HSC is, besides, outstandingly high at early age compare with other HSC, but the compressive strength of G4F HSC, which is vary according to curing temperature and condition, most high at the age after 7 days. Total passed charge of HSC get larger in the order G4FS

• Journal of Korean Society for Atmospheric Environment
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• v.31 no.6
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• pp.548-561
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• 2015

Atmospheric concentrations of polychlorinated dibezo-p-dioxins and furans (PCDD/Fs) were investigated at urban-residential (Group I: Suwon, Guri and Goyang), industrial (Group II: Ansan, Siheung and Bucheon), urban-rural mixed (Group III: Yangju, Pocheon and Dongducheon) and rural regions (Group IV: Yangpyeong) in Gyeonggi-do from February 2012 to November 2012 quarterly. The concentrations of PCDD/Fs ranged from 0.018 to $0.109pgTEQm^{-3}$ in Group I (mean value: $0.061pgTEQm^{-3}$), 0.059 to $0.367pgTEQm^{-3}$ in Group II (mean value: $0.179pgTEQm^{-3}$), 0.072 to $0.836pgTEQm^{-3}$ in Group III (mean value: $0.334pgTEQm^{-3}$) and 0.014 to $0.066pgTEQm^{-3}$ in Group IV (mean value: $0.034pgTEQm^{-3}$), respectively. In spite of the less PCDD/F emission sources than Group II (industrial regions), the level of PCDD/Fs in urban-rural mixed area showed the highest values with high fluctuation. It's likely that the Group III was affected by fugitive emissions such like biomass burning and unregulated open burning. The mean contribution of particle phase to total PCDD/F concentration was above 83% because most of PCDD/F congeners were partitioned into particle phase. We evaluated their gas-to-particles equilibriums with the regression between the particle-gas partition coefficient, $K_P(m^3{\mu}g^{-1})$ and corresponding subcooled liquid vapor pressure ($P_L$). The logarithm-$K_P$ of PCDD/Fs was poorly correlated with $P_L$ at low ambient temperature (below $10^{\circ}C$) and the slope (m) values for log-log plots of the $K_P$ vs. $P_L$ was steeper in the Group 2 and Group 3 than residential area. It implies that the slope values were likely influenced by both the direct emission source of PCDD/Fs and ambient temperature.

• Journal of Digital Convergence
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• v.14 no.8
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• pp.93-104
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• 2016

The purpose of this study was to examine the effects of Family Strength(FS) on the Ethnical Identity(EI) of Third Culture Adolescents and to verify the mediating effect of Self-Esteem(SE) between FS and EI. The subjects of this study were 86 adolescents from two different regions-Fairfax, Virginia and Irvine, California-who are ethnically Korean and hold either Korean or American citizenship. These analyses were carried out with SPSS 18.0, using t-test, one-way ANOVA, corelation analysis, regression analysis and Sobel test to test the significance of a mediation effect. The results of this study are as follows: 1. FS, SE and EI showed a significant positive correlation. 2. SE mediated the effects the relationship between FS and EI. 3. SE had a partial mediation effect on the relationship between FS and Exploration, a sub-variable of EI. SE also had a significant effect on Affirmation, a sub-variable of EI, but there was no significant effect on FS. The results discuss the implication and limitations of this study, and make suggestions for a follow-up study for a healthy ethnic identity formation.

• Pediatric Infection and Vaccine
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• v.28 no.3
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• pp.144-148
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• 2021

Purpose: Nonpharmaceutical measures, such as social distancing, have resulted in unintended consequences, including a decrease in the incidence of childhood diseases. This study aimed to estimate the impact of social distancing on the incidence of febrile seizure (FS) in Korea using nationally representative data. Methods: We used claims data from the Health Insurance Review and Assessment Service, a single-payer database capturing >95% of the Korean population. The database included any inpatient encounter with a FS diagnosis from January 2010 to September 2020 for those aged 0-5 years old. We aggregated the monthly number of cases to estimate the incidence per 100,000 patient-years in 2020 (January 1 to September 30) for the same periods in 2010-2019. Results: The incidence of FS in 2020 ranged from 113 per 100,000 (95% confidence interval [CI], 108-118 per 100,000) in January to 27 per 100,000 (95% CI, 25-30 per 100,000) in September, whereas the average FS incidence in 2010-2019 ranged from 116 per 100,000 (95% CI, 112-121 per 100,000) in January to 101 per 100,000 (95% CI, 97-106 per 100,000) in September. Conclusions: The incidence of FS decreased by -38% in 2020, suggesting that social distancing contributed towards decreasing the incidence of FS.