• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.357-367
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• 2010

In this study, several design and construction cases of the pile bent system for bridges were introduced. The lateral displacement of the pile bent system is larger than the displacement of pile cap system, due to the smaller bending stiffness and the longer unsupported length. So, the analysis of the lateral pile displacement is main factor for the design of pile bent system and superstructure. For the accurate estimation of the pile displacement, an iterative analysis method was developed. The superstructure was analyzed regarding the pile foundation as $6{\times}6$ spring and the substructure was analysed using non-linear load transfer curves (p-y, t-z, q-z curve). And, to verify this analysis method, the estimated displacements are compared with the results of lateral load test. This analysis method is expected to be a viable alternative approach for the design of bridge foundation hereafter.

• Journal of Magnetics
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• v.19 no.2
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• pp.126-129
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• 2014

We report the crystallographic and magnetic properties of $Ni_{0.3}Fe_{0.7}Ga_2S_4$ by means of X-ray diffractometer (XRD), a superconducting quantum interference device (SQUID) magnetometer, and a M$\ddot{o}$ssbauer spectroscopy. In particular, $Ni_{0.3}Fe_{0.7}Ga_2S_4$ was studied by M$\ddot{o}$ssbauer analysis for evidence of spin reorientation. The chalcogenide material $Ni_{0.3}Fe_{0.7}Ga_2S_4$ was fabricated by a direct reaction method. XRD analysis confirmed that $Ni_{0.3}Fe_{0.7}Ga_2S_4$ has a 2-dimension (2-D) triangular lattice structure, with space group P-3m1. The M$\ddot{o}$ssbauer spectra of $Ni_{0.3}Fe_{0.7}Ga_2S_4$ at spectra at various temperatures from 4.2 to 300 K showed that the spectrum at 4.2 K has a severely distorted 8-line shape, as spin liquid. Electric quadrupole splitting, $E_Q$ has anomalous two-points of temperature dependence of $E_Q$ curve as freezing temperature, $T_f=11K$, and N$\acute{e}$el temperature, $T_N=26K$. This suggests that there appears to be a slowly-fluctuating "spin gel" state between $T_f$ and $T_N$, caused by non-paramagnetic spin state below $T_N$. This comes from charge re-distribution due to spin-orientation above $T_f$, and $T_N$, due to the changing $E_Q$ at various temperatures. Isomer shift value ($0.7mm/s{\leq}{\delta}{\leq}0.9mm/s$) shows that the charge states are ferrous ($Fe^{2+}$), for all temperature range. The Debye temperature for the octahedral site was found to be ${\Theta}_D=260K$.

• Journal of Environmental Science International
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• v.21 no.1
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• pp.31-39
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• 2012

The objective of this study is to provide pollutant loads delivery ratio for flow duration in Oenam-cheon watershed, which is upstream watershed of Juam Lake. To calculate the delivery ratio by flow duration, rating curves and discharge-loads curves using measured data were established, then Flow Duration Curve(FDC) and pollutant loads delivery ratio curves were constructed. The results show that the delivery ratios for $BOD_5$ for abundant flow($Q_{95}$), ordinary flow($Q_{185}$), low flow($Q_{275}$), and drought flow($Q_{355}$) were 23.9, 12.7, 7.1, and 2.9%, respectively. The delivery ratios of same flow regime for T-N were 58.4, 31.2, 17.2 and 7.1%, respectively. While, the delivery ratios T-P were 17.3, 7.5, 3.4, and 1.1% respectively. In general, delivery ratio of high flow condition showed higher value due to the influence of nonpoint source pollution. Based on the study results, generalized equations were developed for delivery ratio and discharge per unit area, which could be used for ungaged watershed with similar pollution sources.

• Journal of Korean Society on Water Environment
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• v.28 no.3
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• pp.394-400
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• 2012

We drew the stage-discharge relations of Byeokgye Stream, located in Yangpyeong-gun, Gyeonggi-do, and analysed the correlation between items of water pollutants by measuring the flow rate and water pollutants thirty-four times from April 2010 to December 2010. The results showed that it tended to be low water season from April to June and from October and December, while tending to be water season from July to September. The average flow rate was $2.137\;m^3/sec:\;0.464\;m^3/sec$ in low water season and $13.970\;m^3/sec$ in high water season. The stage-discharge curve thereon was $Q=40.107{\times}(h-1.200)^{2.877}$. As to the correlations, the correlation between the water temperature and COD was 0.58, and the correlations of SS with BOD and COD were 0.46 and 0.40 respectively. The correlation between SS and T-P was 0.73, showing higher than other items.

• Korean Journal of Applied Biomechanics
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• v.31 no.1
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• pp.1-15
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• 2021

Objective: The aim of this study was to investigate 1) the difference in static lower extremity alignment (SLEA) according to a history of lateral ankle sprain (LAS), 2) to identify SLEA factors affecting LAS, and 3) to present the cut-off value and 4) the usefulness and limitations of the SLEA measurement. Method: This case-control study recruited 88 men (age: 27.78±4.69 yrs) and 39 women (age: 24.62±4.20 yrs) subjects with and without LAS. SLEA measurement protocol included Q angle, tibiofemoral angle, genu recurvatum, rear foot (RF) angle, tibal varum and torsion, navicular drop, ankle dorsiflexion range of motion (DF ROM). Independent t-test, logistic regression and receiver operating characteristic (ROC) curve were used for statistical analysis. Results: Men with a history of LAS had significantly smaller Q angles both in standing and in supine position, while women with a history of LAS had significantly greater DF ROM in non-weight bearing (NWB; p < 0.05). Logistic regression model suggests tibial varum (OR = 0.779, p = 0.021) and WB DF ROM (OR = 1.067, p = 0.045) were associated with LAS in men. In case of women, there were no significant SLEA factors for LAS, however, ROC curve analysis revealed standing RF angle (AUC = 0.647, p = 0.028) and NWB DF ROM (AUC = 0.648, p = 0.026) could be affecting factors for LAS. Conclusion: There are differences in SLEA according to the history of LAS, furthermore, the identified items were different by sex. In case of men, tibial varum and WB DF ROM affect LAS occurrence. Standing RF angle and NWB DF ROM of women could be a predictor for LAS. However, since the sensitivity and specificity in most of the SLEA measurements are low, kinematic in dynamic tasks should be considered together for a more accurate evaluation of LAS risk.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.5 no.1
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• pp.10-17
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• 1993

This paper describes the boiling heat transfer phenomena to be divided into three regions, nonboiling, nucleate boiling and burn-out in the impinging subcooled water jet system. In the nonboiling region, Nusselt number is a function of Prandtl number, Reynolds number and ${\Delta}T_{sub}/T_{ast}$ In the nucleate boiling region, the heat flux increases with increment of the nozzle exit velocity. But the degree of liquid subcooling does not affect the shape of the nucleate boilng curve. The dimensionless correlations can be expressed in the form of $q{\ell}/K_f{\Delta}T_{ast}=C(Bo{\cdot}C_p{\cdot}{\Delta}T_{sat}/Vo^2)^m{\cdot}(Re/We)^n$. The burn-out heat flux increases linearly with increment of the nozzle exit velocity, but independs of degree of subcooling and the supplementary water height.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6273-6276
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• 2012

Background/Aim: Six prostate cancer (PCa) susceptibility loci were identified in a genome-wide association study (GWAS) in populations of European decent. However, the associations of these 6 single-nucleotide polymorphisms (SNPs) with PCa has remained tobe clarified in men in Northern China. This study aimed to explore the loci associated with PCa risk in a Northern Chinese population. Methods: Blood samples and clinical information of 289 PCa patients and 288 controls from Beijing and Tianjin were collected. All risk SNPs were genotyped using polymerase chain reaction (PCR)-high resolution melting curve technology and gene sequencing. Associations between PCa and clinical covariates (age at diagnosis, prostate-specific antigen [PSA], Gleason score, tumor stage, and level of aggressiveness) and frequencies of alleles and genotypes of these SNPs were analyzed using genetic statistics. Results: Among the candidate SNPs, 11p15 (rs7127900, A) was associated with PCa risk (P = 0.02, odds ratio [OR] = 1.64, 95% confidence interval [CI] = 1.09-2.46). Genotypes showed differences between cases and controls on 11p15 (rs7127900, A), 11q13 (rs7931342, T), and HNF1B (rs4430796, A) (P = 0.03, P = 0.01, and P = 0.04, respectively). The genotype TG on 11q13 (rs7931342, T) was positively associated with an increased Gleason score (P = 0.04, OR = 2.15, 95% CI = 1.02-4.55). Patients carrying TG on 17q24 (rs1859962, G) were negatively associated with an increased body mass index (BMI) (P = 0.03, OR = 0.44, 95% CI = 0.21-0.92) while those with AG on HNF1B (rs4430796, A) were more likely to have PSA increase (P = 0.002). Conclusion: Our study suggests that 11p15 (rs7127900, A) could be a susceptibility locus associated with PCa in Northern Chinese. Genotype TG on 11q13 (rs7931342, T) could be related to an increased Gleason score, AG on HNF1B (rs4430796, A) could be associated with PSA increase, and TG on 17q24 (rs1859962, G) could be negatively associated with an increased BMI in Chinese men with PCa.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.41.1-41.1
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• 2016

We present the physical properties of KIC 6220497 exhibiting multiperiodic pulsations from the Kepler photometry. The light curve synthesis represents that the eclipsing system is a semi-detached Algol with a mass ratio of q=0.243, an orbital inclination of i=77.3 deg, and a temperature difference of ${\Delta}T=3,372K$, in which the detached primary component fills its Roche lobe by ~87% and is about 1.6 times larger than the lobe-filling secondary. To detect reliable pulsation frequencies, we analyzed separately the Kepler light curve at the interval of an orbital period. Multiple frequency analyses of the eclipse-subtracted light residuals reveal 32 frequencies in the range of $0.75-20.22d^{-1}$ with semi-amplitudes between 0.27 and 4.55 mmag. Among these, four frequencies ($f_1$, $f_2$, $f_5$, $f_7$) may be attributed to pulsation modes, while the other frequencies can be harmonic and combination terms. The pulsation constants of 0.16-0.33 d and the period ratios of $P_{pul}/P_{orb}=0.042-0.089$ indicate that the primary component is a ${\delta}$ Sct pulsating star in p modes and, thus, KIC 6220497 is an oscillating eclipsing Algol (oEA) star. The dominant pulsation period of about 0.1174 d is considerably longer than the values given by the empirical relations between the pulsational and orbital periods. The surface gravity of log $g_1=3.78$ is significantly smaller than those of the other oEA stars with similar orbital periods. The pulsation period and the surface gravity of the pulsating primary demonstrate that KIC 6220497 would be the more evolved EB, compared with normal oEA stars.

• Korean Journal of Environment and Ecology
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• v.37 no.5
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• pp.347-366
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• 2023

In the present study, the vegetation was classified using the phytosociological method and canonical-correlation analysis (CCA) was implemented to analyze correlation between community structure and environmental factors in the natural habitats of forest byproducts, especially medicinal plants, such as Cudrania tricuspidata, Sorbus commixta, and Hovenia dulcis, in 2021-2022 to provide primary ecological data to establish environmental conditions for wild vegetable cultivation. A total of 11 plots in five regions, 8 plots in three regions, and 17 plots in 5 regions were selected for the natural habitats of C. tricuspidata in southern Korea, S. commixta in high mountains, and H. dulcis in valleys of central Korea, respectively. The importance value in each community was respectively analyzed as follows, in C. tricuspidata community, the importance value of C. tricuspidata (61.10) was the highest, followed by Celtis sinensis, Pinus thunbergii, Neolitsea aciculata, Styrax japonica, Carpinus coreana, Quercus serrata, and Q. acutissima. In Sorbus commixta community, Q. mongolica (57.21) was the highest, followed by, S. commixta (42.58), Betula ermani, Tilia amurensis, A. pseudosieboldianum, A. tschonoskii var. rubripes, Cornus controversa, Magnolia sieboldii, and Taxus cuspidata. In H. dulcis community, H. dulcis (64.58) was the highest, followed by Zelkova serrata, Cornus controversa, A. mono, Q. serrata, C. cordata, and Juglans mandshurica. As the result of the analysis on DBH of the major species having the high importance value, in C. tricuspidata community, C. tricuspidata, C. sinensis, Neolitsea aciculata, and C. coreana show the density of normal distribution, so the dominant status of these species is likely to continue. In S. commixta community, S. commixta show the density of reverse J-shaped curve, so the dominant status of these species is likely to be stable, and Q. mongolica, B. ermani and T. amurensis, show the density of normal distribution, so the dominant status of these species is likely to continue. In H. dulcis community, C. cordata, and J. mandshurica show the density of reverse J-shaped curve, so the dominant status of these species is likely to be stable, and H. dulcis, Z. serrata, C. controversa and A. mono had a formality distribution, suggesting a continuous domination of these species over the other species for the time being. The results of CCA ordination analysis using 11 environmental factors and 30 communities of three taxa classified by TWINSPAN analysis revealed that the altitude showed the strongest correlation with the vegetation. C. tricuspidata community was distributed on the moderate and gentle northeastern slope at low altitude with the highest pH, C.E.C, Ca²⁺, and Mg² and various P₂O₅, whereas S. commixta community was distributed on the steep slope at high altitude with the highest O.M and T-N and lower P₂O₅, Ca²⁺, Mg²⁺, C.E.C and pH, which is the opposite tendency of the environment of C. tricuspidata community. H. dulcis community was distributed on the gentle northern slope at lower altitude with an average pH, O.M, T-N, Ca²⁺, Mg²⁺, and C.E.C, except higher P₂O₅.

• Journal of Korean Society on Water Environment
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• v.31 no.6
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• pp.653-664
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• 2015

TPLMS (Total water pollutant load management system) that is the most powerful water-quality protection program have been implemented since 2004. In the implementation of TPLMS, target water-quality and permissible discharged load from each unit watershed can be decided by water-quality modeling. And NPS (Non-point sources) discharge coefficients associated with certain (standard) flow are used on estimation of input data for model. National Institute of Environmental Research (NIER) recommend NPS discharge coefficients as 0.15 (Q₂₇₅) and 0.50 (Q₁₈₅) in common for whole watershed in Korea. But, uniform coefficient is difficult to reflect various NPS characteristics of individual watershed. Monthly NPS discharge coefficients were predicted and estimated using surface flow and water-quality from HSPF watershed model in this study. Those coefficients were plotted in flow duration curve of study area (Palger stream and Geumho C watershed) with monthly average flow. Linear regression analysis was performed about NPS discharge coefficients of BOD, T-N and T-P associated with flow, and R² of regression were distributed in 0.893~0.930 (Palger stream) and 0.939~0.959 (Geumho C). NPS Discharge coefficient through regression can be estimated flexibly according to flow, and be considered characteristics of watershed with watershed model.