• Journal of dental hygiene science
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• v.12 no.6
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• pp.689-695
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• 2012

The aim of this study was to elucidate the effects of concentrated growth factors (CGFs) on human gingival fibroblasts in vitro. Blood was collected from three male volunteers (average age 27 years). CGFs were prepared using standard protocols. The CGF exudates were collected at the following culture time points: 1, 7, 14, and 21 days. The levels of platelet-derived growth factor BB (PDGF-BB) and transforming growth factor ${\beta}1$ (TGF-${\beta}1$) in CGFs were quantified. The CGF exudates were then used to culture human gingival fibroblasts. The biologic characteristics of these fibroblasts were analyzed in vitro for 21 days. Platelet-rich plasma released the highest amounts of TGF-${\beta}1$ and PDGF-BB on the first day. The level of TGF-${\beta}1$ had decreased slightly by day 7, although the difference compared to levels at day 1 was not statistically significant. However, by days 14 and 21, levels of TGF-${\beta}1$ had dropped significantly compared to day 1 levels. The levels of PDGF-BB at days 7, 14, and 21 did not differ significantly from that measured on day 1. CGFs maintained the release of autologous growth factors for a reasonable period of time (7 days for TGF-${\beta}1$ and 21 days for PDGF-BB). Gingival fibroblasts treated with CGF exudates collected at day 14 reached peak viability and synthesized type I collagen. Furthermore, the CGF exudates exerted positive effects on the proliferation and differentiation of these cells at days 1, 7, 14, and 21. The findings of this study suggest that treatment with CGFs represents a promising method of enhancing mucosal healing following surgical procedures.

• Journal of the Korean Solar Energy Society
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• v.36 no.1
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• pp.27-37
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• 2016

A simple but practical Ensemble Prediction System(EPS) for wind power forecasting was developed and evaluated using the measurement of the offshore meteorological tower, HeMOSU-1(Herald of Meteorological and Oceanographic Special Unite-1) installed at the Southwest Offshore in South Korea. The EPS developed by the Korea Institute of Energy Research is based on a simple ensemble mean of two Numerical Weather Prediction(NWP) models, WRF-NMM and WRF-ARW. In addition, the Kalman Filter is applied for real-time quality improvement of wind ensembles. All forecasts with EPS were analyzed in comparison with the HeMOSU-1 measurements at 97 m above sea level during Typhoon Bolaven episode in August 2012. The results indicate that EPS was in the best agreement with the in-situ measurement regarding (peak) wind speed and cut-out speed incidence. The RMSE of wind speed was 1.44 m/s while the incidence time lag of cut-out wind speed was 0 hour, which means that the EPS properly predicted a development and its movement. The duration of cut-out wind speed period by the EPS was also acceptable. This study is anticipated to provide a useful quantitative guide and information for a large-scale offshore wind farm operation in the decision making of wind turbine control especially during a typhoon episode.

• Korean Journal of Optics and Photonics
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• v.14 no.3
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• pp.266-271
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• 2003

The reflectance spectrum of optical films thicker than a few microns shows an intensity oscillation due to interference. Since the spectral period of the oscillation is inversely related to film thickness, the thickness of an optical film can be determined from the spectral frequency of the oscillation. For rapid data processing, the spectral frequency is obtained by use of a Fast Fourier Transformation technique. The conventional method of applying a Fast Fourier Transformation to the reflectance spectrum versus photon energy is modified so as to clear the ambiguity in choosing the proper effective refractive index value and to prevent the broadening of the Fourier transformed peak due to the refractive index dispersion. This technique of modified Fast Fourier Transformation is suggested by the authors for the first time to their knowledge. From the analysis of the calculated reflectance spectrum of a 30-${\mu}{\textrm}{m}$-thick dielectric film. it is shown to improve the accuracy in determining film thickness by a great amount. The improved accuracy of the modified Fast Fourier Transformation is also confirmed from the analysis of the reflectance spectra of a sample with 80-${\mu}{\textrm}{m}$-thick cover layer and 13-${\mu}{\textrm}{m}$-thick spacer layer on a PC substrate.

• Korea journal of population studies
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• v.8 no.2
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• pp.79-92
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• 1985

Fertility has been declined since 1966 (see Table 1). This fertility reduction was duely caused by age at first marriage, induced abortion and contraceptive practice which has been largely increased in recent years. Although tbe proximate determinant such as induced abortion, age at marriage and breastfeeding can and do have an effect on fertility, the principal cause of the reduction in fertility in Korea during the fertility transition can be supported by correlation between level of fertility and contraceptive prevalence (See Fig. 4). Taking a regression equation between fertility (TER. Y) and prevalence level (X), the total fertility rate in 1984 was estimated as 1.9 and 2.1 based on lenear and expotential function shown as follow; $Y_1$=5.709-0.0549 X and $Y_2$_______80________ 1+e2.433+0.017X ($R^2$=O. 93) ($R^2$=0. 96) Where $Y_1$ and $Y_2$ denote total fertility rates obtained through two equations respectivelly. The peak of contraceptive prevalence was assumdd as 80 percent which is almost upper limit in human society. On the other hand, an observed value of 1984 fertility level obtained from five month period shows 2.1 which is coincident with logistic fitting after the adjustment of response error assumed around 10 to 20 percent, At any rate, fertility of Korean women will have been reached replacement level (2.1) by 1985.Thus policy for family planning program must be reviewed toward the direction of integrated approach particularly with MCH program inasmuch as fertility in Korea has already shown population replacement level that require more good quality of service in family planning and their There must be an advanced level of fertility in Korea because wide use of contraception and induced life abortion and age at marriage will effect modern fertility which shows up and down trend between 2.1 and 1.5 in general.

• Journal of Surface Science and Engineering
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• v.54 no.5
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• pp.238-247
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• 2021

PEO (plasma electrolytic oxidation) was applied to modify the surface of AZ31 magnesium alloy in this study. The mixed solution of sodium hydroxide (NaOH) and sodium silicate (Na₂SiO₃) was used as the electrolyte, and 0 - 0.05 g/L of Ca-GP (Glycerol Phosphate Calcium salt) was added in the electrolyte as an additive. PEO treatment was conducted at a current density of 30mA/cm² for 5 minutes using a DC power supply. The surface properties were identified by SEM, XRD and surface roughness analyses, and the corrosion resistance was evaluated by potentiodynamic polarization and immersion tests. In addition, the biocompatibility was evaluated by immersion test in SBF solution. As the concentration of Ca-GP was increased, the surface morphology was denser and more uniform, and the amount of Ca and the thickness of oxide layer increased. Only Mg peak was observed in XRD analysis due to very thin oxide layer. The corrosion resistance of PEO-treated samples increased with the concentration of Ca-GP in comparision with the untreated sample. In particular, the highest corrosion resistance was identified at the group of 0.04g Ca-GP through potentiodynamic polarization and immersion tests in saline solution (0.9 wt.%NaCl). During the immersion in saline solution, pH rapidly increased at the beginning of immersion period due to rapid corrosion, and then increase rate of pH decreased. However, the pH value in the SBF temporarily increased from 7.4 to 8.5 during the day, then decreased due to the inhibition of corrosion with HA(hydroxyapatite) formation.

• Investigative and Clinical Urology
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• v.59 no.6
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• pp.383-391
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• 2018

Purpose: We aimed to analyze the incidence and prevalence of urolithiasis in Korea over the last decade using the National Health Insurance (NHI) sample cohort data. Materials and Methods: From January 2002 to December 2013, we enrolled sample cohort data from the NHI. Patients diagnosed with international classification of diseases code N20 or N13.2 were included. The incidence and prevalence rate was counted from the same period and patients previously diagnosed with urolithiasis were excluded. We compared the incidence and prevalence of urolithiasis by region, age, and sex, and identified the changes. Results: Total 1,111,828 subjects were included. Of these subjects, 36,857 had urolithiasis. The male-to-female ratio was 1.57:1, and total incidence rate was 3.27 per 1,000 person-years (1,000p-yrs). The annual incidence was lowest in 2013 (3,138 patients) and highest in 2005 (3,751 patients). Incidence rate by diagnostic code was highest in ureter stone only (2.49 per 1,000p-yrs) and was lowest in kidney and ureter stone both (0.17 per 1,000p-yrs). Prevalence gradually increased from 3,172 in 2002 and 5,758 in 2013. Jeollanam-do had the highest incidence rate of 3.70 persons per 1,000p-yrs, and Jeju had the lowest rate of 2.84 persons per 1,000p-yrs. In gender analysis, Daegu had the highest incidence (4.56) in males, Jeollanam-do had the highest incidence (3.20) in females. Conclusions: Annual incidence remained stable, whereas prevalence gradually increased. The incidence in male was 1.57 times higher than female, and the peak incidence age was 45-49 years, with the highest incidence occurring in Jeollanam-do and the lowest in Jeju.

• Ocean Systems Engineering
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• v.9 no.3
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• pp.287-328
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• 2019

Comprehensive understanding of the flood risk assessments via frequency analysis often demands multivariate designs under the different notations of return periods. Flood is a tri-variate random consequence, which often pointing the unreliability of univariate return period and demands for the joint dependency construction by accounting its multiple intercorrelated flood vectors i.e., flood peak, volume & durations. Selecting the most parsimonious probability functions for demonstrating univariate flood marginals distributions is often a mandatory pre-processing desire before the establishment of joint dependency. Especially under copulas methodology, which often allows the practitioner to model univariate marginals separately from their joint constructions. Parametric density approximations often hypothesized that the random samples must follow some specific or predefine probability density functions, which usually defines different estimates especially in the tail of distributions. Concentrations of the upper tail often seem interesting during flood modelling also, no evidence exhibited in favours of any fixed distributions, which often characterized through the trial and error procedure based on goodness-of-fit measures. On another side, model performance evaluations and selections of best-fitted distributions often demand precise investigations via comparing the relative sample reproducing capabilities otherwise, inconsistencies might reveal uncertainty. Also, the strength & weakness of different fitness statistics usually vary and having different extent during demonstrating gaps and dispensary among fitted distributions. In this literature, selections efforts of marginal distributions of flood variables are incorporated by employing an interactive set of parametric functions for event-based (or Block annual maxima) samples over the 50-years continuously-distributed streamflow characteristics for the Kelantan River basin at Gulliemard Bridge, Malaysia. Model fitness criteria are examined based on the degree of agreements between cumulative empirical and theoretical probabilities. Both the analytical as well as graphically visual inspections are undertaken to strengthen much decisive evidence in favour of best-fitted probability density.

• Journal of the Korean Society of Physical Medicine
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• v.14 no.1
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• pp.63-73
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• 2019

PURPOSE: This study examined the effects of cardiopulmonary physiotherapy on the cardiopulmonary function, metabolism, inflammatory markers, and quality of life in patients with coronary artery disease who underwent percutaneous coronary intervention (PCI). METHODS: Electronic bibliographic databases of a regional information sharing system (RISS) and PubMed were searched to identify studies with randomized and non-randomized controlled trials. As the final outcome, 320 publications were identified and 18 studies met the inclusion and exclusion criteria. All studies were assessed for the quality of study using Cochrane's risk of bias. RESULTS: Sixteen studies met the inclusion criteria, in which meta-analysis had been conducted to examine the effectiveness of cardiopulmonary physiotherapy on the cardiopulmonary function, metabolism, inflammatory markers, and quality of life in patients undergoing PCI. Meta-analysis based on a random effect model showed that the cardiopulmonary physiotherapy was beneficial in improving the cardiopulmonary function, metabolism, inflammatory markers, and quality of life. In particular, there was a significant effect on the peak oxygen uptake (effect size 5.30%; 95% confidence interval 3.62~6.97). Cardiopulmonary physiotherapy for a during period of 6 weeks or more was effective in significantly improving the cardiopulmonary function and metabolism function in a subgroup analysis, but cardiopulmonary physiotherapy for less than 6 weeks was not effective. CONCLUSION: Cardiopulmonary physiotherapy has positive effects on the cardiopulmonary function, metabolism, inflammatory markers, and quality of life in patients undergoing PCI.

• Korean Journal of Ichthyology
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• v.30 no.4
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• pp.217-223
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• 2018

The study on the spawning ecology of Sarcocheilichthys variegatus wakiyae at Jicheon stream, Korea was investigated from March 2016 to February, 2017. The sex ratio of male to female was 1 : 0.97 and there was no significant difference. The spawning season was from the end of April to the mid-July, and the peak of spawning period was from the beginning of May to the end of June. The average water temperature at this time was $18^{\circ}C$. According to frequency analysis of total length, it is presumed that the group with a total length of less than 51~70 mm was one year old, the 71~100 mm was two years old, and the group over 101 mm was three years old. They sexually matured when they were over two years. The average number of eggs in the ovaries was estimated as $428{\pm}194per$ matured female. The mature eggs were yellowish, oval, and had a mean diameter of $2.38{\pm}0.25mm$ and a short diameter of $1.98{\pm}0.20mm$.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.4
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• pp.599-606
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• 2019

Objective: The present study was carried out to evaluate the effect of high dietary cation and anion difference (DCAD) rations on diurnal variations in eating and meal patterns, water intake and urination patterns in dairy goats fed under high ambient temperature (HTa). Methods: Ten crossbred dairy goats during peri-parturition period were selected and divided into two groups of five animals each. Experimental diets were control DCAD (control, 22.8 mEq/100 g dry matter [DM]) and high DCAD (DCAD, 39.1 mEq/100 g DM). The composition of two diets consisted of 44% corn silage and 56% concentrate. From the 2nd week to 8th week postpartum, goats were fed ad libitum twice daily either with the control or DCAD total mix ration with free access to water. The spontaneous eating and drinking patterns were determined. Results: The environmental conditions in the present experiment indicated that goats were fed under HTa conditions (average peak THI = 85.2) and were in heat stress. In addition to the typical HTa induced tachypnoea in both groups, the respiratory rate in the DCAD group was significantly higher than the control group (p<0.05). Although the goats from both groups showed comparable level of eating, drinking and urination during experiment, the meal pattern and water intake were different. High DCAD apparently increased eating and meal patterns compared with the control. At week 8 postpartum, goats from high DCAD group had significant (p<0.05) bigger meal size and longer meal duration. Moreover, high DCAD appeared to increase night-time water intake (p<0.05). Conclusion: Both meal pattern and night-time drinking effects of DCAD suggested that feeding with high DCAD ration may alleviate the effect of heat stress in dairy goat fed under HTa conditions.