• Atmosphere
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• v.34 no.3
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• pp.305-317
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• 2024

The study examines the effects of parameters that define the characteristics of raindrops on the simulated precipitation during the summer season over Korea using the Weather Research and Forecasting (WRF) Double-Moment 6-class (WDM6) cloud microphysics scheme. Prescribed parameters, defining the characteristics of hydrometeors in the WDM6 scheme such as a_R, b_R, and f_R in the fall velocity (V_R) - diameter (D_R) relationship and shape parameter (𝜇_R) in the number concentration (N_R) - D_R relationship, presents different values compared to the observed data from Two-Dimensional Video Disdrometer (2DVD) at Boseong standard meteorological observatory during 2018~2019. Three experiments were designed for the heavy rainfall event on August 8, 2022 using WRF version 4.3. These include the control (CNTL) experiment with original parameters in the WDM6 scheme; the MUR experiment, adopting the 50th percentile observation value for 𝜇_R; and the MEDI experiment, which uses the same 𝜇_R as MUR, but also includes fitted values for a_R, b_R, and f_R from the 50th percentile of the observed V_R - D_R relationship. Both sensitivity experiments show improved precipitation simulation compared to the CNTL by reducing the bias and increasing the probability of detection and equitable threat scores. In these experiments, the raindrop mixing ratio increases and its number concentration decreases in the lower atmosphere. The microphysics budget analysis shows that the increase in the rain mixing ratio is due to enhanced source processes such as graupel melting, vapor condensation, and accretion between cloud water and rain. Our study also emphasizes that applying the solely observed 𝜇_R produces more positive impact in the precipitation simulation.

• Korean Journal of Veterinary Research
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• v.31 no.2
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• pp.179-187
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• 1991

These studies were carried out to investigate the effects of the size of follicles, semen types, capacitation methods, and additions of hormones, estrous cow serum(ECS), fetal calf serum(FCS), bovine follicular fluid(BFF) and matured cumulus cell(MCC) to the medium on in vitro maturation and fertilization of bovine follicular oocytes. The ovaries were obtained from slaughtered Korean native cows. The follicular oocytes surrounded with cumulus cells were recovered by aspirating follicular fluid from the visible follicles of diameter 3~5mm. The follicular oocytes were cultured in TCM-199 medium containing hormones, FCS, ECS, BFF and MCC for 24~48hrs. in an incubator with 5% $CO_2$ in air at $38.5^{\circ}C$ and then matured oocytes were again cultured for 18~20 hrs. with motile capacitated spermatozoas the TCF (Tyrode calcium free) solution containing $100{\mu}g/ml$ of heparin. The results obtained in these experiments were summarized as follows: 1. The oocytes classified as "A,B,C,D and Degenerative" depending morphological integrity and those 61.4%, 12.1%, 19.2%, 4.2% and 3.0% of the total oocytes recovered, respectively. The maturation and fertilization rate of the A, B, C class follicular oocytes, cultured in the TCM-199 medium supplemented with 10% FCS were 89.1%, 78.0%, 52.6% and 78.1%, 66.1, 33.3%, respectively. 2. The average number of the follicular oocytes recovered from follicles size, 1~2mm, 3~5mm and above 5mm in diameter were 67, 98 and 63, respectively. The maturation and fertilization rate of the follicular oocytes, cultured in the TCM-199 medium were 56.7%, 82.5%, 46.0% and 44.8%, 71.4%, 28.6%, respectively. 3. The fertilization and cleavage rate of the follicular oocytes, inseminated with spermatozoas of epididymal cauda, neat and frozen semen were 63.3%, 73.3%, 70.0% and 32.7%, 37.8% 38.3%, respectively. 4. The fertilization and cleavage rate of follicular oocytes, fertilized with capacitated spermatozoas by heparin, BFF and HIS methods were 70.0%, 53.8%, 34.2% and 38.3%, 23.1%. 17.1%, respectively. And the fertilization and cleavage rate were higher method of heparin. 5. The maturation and fertilization rate of follicular oocytes, cultured in the TCM-199 medium supplemented with 5%, 10%, 15%, 20% and FSH, HCG, 17, $\beta$-estradiol were 76.0~82.3% and 26.2~70.0%, and those values were higher the supplementation than non-supplementation. 6. The maturation and fertilization rate of the follicular oocytes cultured in TCM-199 medium supplemented with 5~20% ECS and FCS were 74.0~80.6%, 26.2~30.0% and 71.7~76.9%, 51.9~58.0%, and the values were higher the supplement of ECS than FCS. 7. The maturation rate (68.0~64.6%) and fertilization rate(59.6~60.4%) of follicular oocytes cultured in TCM-199 medium supplemented with 10% FCS and 20~30% BFF were higher than those of follicular oocytes cultured TCM-199 medium supplemented with 10% FCS and 10% and 50% BFF. 8. The maturation rate(76.5%) and fertilization rate (61.7%) of follicular oocytes cultured in TCM-199 medium supplemented with 10% FCS and $1{\times}10^6/ml$ MCC were higher than those of follicular oocytes cultured in TCM-199 medium supplemented with 10% FCS and $1{\times}10^{{4}{\sim}{5}}/ml$ and $1{\times}10^8/ml$ cumulus cells.

• Journal of Korean Society of Forest Science
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• v.17 no.1
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• pp.35-42
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• 1973

Deciduous trees grown naturally in the forest of Korea usually have an irregular Lee-form and their utility has been decreased. In Korea, most of the deciduous stands are distributed in the hinterland. A shortage of the total growing stock made utilization of them necessary in this country even though some difficulties to be cutted and transported are accompanied. Therefore, this study was conducted to select the suitable sampling method for surveying them. The results investigated are as follows. 1. Three locations being 10 hectares in each location for the plots were chosen and surveyed with six $20m{\times}50m$ rectangular sample plots by four types of sampling method below. And the result is shown in Table 1. A. Random sampling by grids B. Random sampling by co-ordinates C. Systematic line plot. D. Sub-sampling 2. One hundred and fifty hectares from all plots were sectioned through the application of aerial photography scaled of 1 : 15,000. The author divided forest types according to diameter class and crown density with mirror stereoscope. The forest types were divided into three classes. Seven sample plots from the area of 150 hectars are systematically arranged and the results investigated on the circular sample point of 0.1 hectare are shown in Table 4. 3. There were no significant differences between results by sampling method and by diameter measurement method (population mean) as shown in Table 3. 4. Random sampling by grid and systematic line plot are better than others. 5. There are more over-estimated values when the circular sample point is used than where the rectangular sample point. 6. As forest stands are irregular, smaller number of sample points will make many errors.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.1
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• pp.23-35
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• 2010

For the sustainable conservation of forests within and around the somma of Nari basin in Ulleung Island, the stand structure and dynamics with the aspect, altitude and stand types were estimated by using analyses of importance value, plant species diversity, S$\o$rensen's similarity index and distributions of diameter classes. Results of the importance value analysis with vegetation stories on each stand showed that Fagus engleriana and Acer okamotoanum were dominant in most stands regardless of the aspect and altitude of the forest around the somma of Nari basin and the plant species composition among stands was not significantly different. The forest within Nari basin was composed of pine, beech, alder and deciduous-mixed stand. Moreover, the species composition was greatly different among the four stands. The diversity of plant species within stand was in general higher within Nari basin than around the somma, and among stands within Nari basin, the plant species diversity of pine and deciduous-mixed stand showed higher values than that of beech and alder stands. The similarity index among stands with aspect and altitude showed that the index among stands of eastern, western and northern slope in forest around the somma and forest within the basin ranged from 0.68 to 0.69, and the similarity among four stands with altitude was very high having index range from 0.85 to 0.95. The patterns of diameter class distribution of the major dominant species from four altitude classes followed an almost normal bell-shaped distribution. The results were interpreted as an indication that these forests will in general maintain a stable stand structure. Therefore, despite diverse topographic features around Nari basin, the stand structure and plant species composition among stands were not diversified as expected. For the conservation of diversity of forest plant species and of forest ecosystems, a promising and intensive program should be considered.

• The Journal of the Korea Contents Association
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• v.14 no.5
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• pp.251-261
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• 2014

Primary percutaneous coronary intervention (PCI) has been found to be superior, in terms of hospital mortality and long-term outcome, compared with thrombolytic therapy in patients with acute myocardial infarction (AMI). However, the clinical benefits of primary PCI have not been precisely evaluated in elderly patients.1,974 patients (Group I: n=1,018, $age{\geq}65years$, $73.8{\pm}5.99years$; Group II: n=956, age<65years, $52.8{\pm}7.96years$) who underwent primary PCI for AMI at Chonnam National University Hospital between 2006 and 2010 were analyzed according to their clinical, angiographic characteristics for hospital and one-year survival. Group I had a higher percentage of women, diabetes mellitus, hypertension, multi-vessel disease and lower prevalence of current smoking, hyperlipidemia, familial history than Group II. Culprit lesions were at the left anterior descending artery, left circumflex artery, right coronary artery and left main artery in 42.8% vs. 45.0%, 34.1% vs. 29.6%, 14.6% vs 14.6, 2.7% vs. 1.6%, respectively (p=0.007). Stent diameter was smaller in group I ($3.17{\pm}0.39$ vs. $3.29{\pm}0.42mm$, p=0.001). In-hospital mortality was higher in group I (8.4 vs. 1.9%, p<0.001). There were significant differences in the rates of major adverse cardiac events between the two groups during one-year clinical follow-up (20.1 vs.14.0%, p<0.001). On multiple logistic regression analysis, systolic blood pressure<100mmHg, serum $creatinine{\geq}1.3mg/dL$, Killip class> I, multivessel disease, left ventricular ejection fraction <40% and cerebro vascular disease were independent predictors of one-year motality in patients over 65 years after PCI.

• The korean journal of orthodontics
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• v.41 no.2
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• pp.87-97
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• 2011

Objective: Facial asymmetry is usually evaluated from the difference in length and angulation of the maxilla and mandible. However, asymmetric position or shape of the condyle can also affect the expression of asymmetry. The purpose of this study was to evaluate the correlation between condylar asymmetry and chin point deviation in facial asymmetry. Methods: Cone-beam CT images of fifty adult skeletal Class III patients were studied. Thirty patients who had more than 4 mm menton deviation were categorized in the asymmetric group. Twenty patients with less than 4 mm menton deviation were assigned to the symmetric group. Anteroposterior and transverse condyle positions were evaluated from the cranial base. The greatest mediolateral diameter (GMD) of the condyle in the axial plane and angulation to the coronal plane were measured. The height and volume of the condyles were evaluated. Results: The symmetric group had no statistical difference between both condyles in position, angulation, GMD, height and volume. In the asymmetric group, the non-deviated side condyle was larger in GMD, height and volume than the deviated side. There was no statistical difference in condyle position and angulation. The GMD, height difference and condylar volume ratio (non-deviated/deviated) were positively correlated with chin deviation. From the linear regression analysis, condylar volume ratio was a significant factor affecting chin deviation. Conclusions: These findings suggests that the non-deviated side condyle is larger than the deviated side. In addition, condylar asymmetry can affect the expression of facial asymmetry.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.43-54
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• 2001

Genetic differentiation of populations is resulted from the environmental and the genetic effects, and the interactions between them. Whereas, the major factors influencing to the genetic differentiation within populations are the gene flow induced by seed or pollen dispersial, the microsite heterogeneity, and the density-dependent distribution of individuals. For the purpose of studying spatial genetic structure and the distribution pattern of Korean pines(Pinus koraiensis), we set up one $100{\times}100m$ plot at a Korean pine stand in Quercus mongolica community on Mt. Jumbong in Korea. To estimate the coefficient of spatial autocorrelation as Moran's index and an analogue, simple block distance, isozyme markers were analyzed in 325 Korean pines. For 11 polymorphic loci observed in 9 enzyme systems, the average percentage of polymorphic loci, the observed and expected heterozygocity were 72.2% 0.200, and 0.251, respectively. It was revealed the excess of homozygotes was observed in the plot, which suggests that here may be more number of consanguineous trees than expected. On the basis of isozyme genotypes observed in this study, 325 trees were classified into 147 groups in which the maximum number of trees for one group was 34. From the distance class of 24-32m, the genetic heterogeneity began to increase. The variation of simple block distance against the growth performance by tree height and diameter also showed the same trend at 24~32m class. According to high fixation index(F=0.204), the spatial genetic structure within a stand, the analysis of the growth performance, and the distribution patterns of identical genotypes, we inferred that the genetic structure of a Korean pine stand in Mt. Jumbong has been maintained rather density-dependent mechanism than the gene flow, such as the pollen dispersial or the heavy input of seeds following the forest gaps. The genetic patchy size was determined between 24~32m, which suggests that the selection of individuals for the ex situ conservation of Korean pine in Mt. Jumbong may be desirable to be made with the spatial distance over 37 meters between trees.

• Journal of Korean Society of Forest Science
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• v.113 no.2
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• pp.222-238
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• 2024

Coniferous species in subalpine ecosystems are known to be highly sensitive to climate change. Therefore, it is becoming increasingly important to monitor community and population dynamics. This study monitored 37 plots within the distribution area of Abies koreana on Mt. Jirisan for a period of eight years. We analyzed the importance value, density of living stems, mortality rate, recruitment rate, basal area, DBH (diameter of breast height) class distribution, and tree health status. Our results showed changes in the importance value based on the tree stratum, with A. koreana decreasing by 3.6% and Tripterygium regelii increasing by 2.5% in the tree layer. Between 2015 and 2023, there were 149 dead trees/ha (17.99% mortality rate) and 12 living trees/ha (1.02% recruitment rate) of A. koreana. The decrease in basal area was attributed to a decrease in the number of living trees. Tree mortality occurred in all DBH classes, with a particularly high decline in the <10 cm class (65 trees/ha reduced). In terms of changes in tree health status, the population of alive standing (AS) type trees, initially consisting of 539 trees/ha, has been transformed into alive standing (AS), alive lean (AL), and death standing (DS), accounting for 69.7%, 0.5%, and 13.8%, respectively. Meanwhile, DS-type trees have transitioned into dead broken (DB) and dead fallen (DF) types. This phenomenon is believed to be caused by strong winds in the subalpine region that pull up the rootlets from the soil. Further research on this finding is recommended.

• Journal of Chest Surgery
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• v.43 no.6
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• pp.635-641
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• 2010

Background: Radiofrequency endovenous ablation of incompetent saphenous vein has gaining popularity over the conventional ligation and stripping as a minimally invasive technique. The latest version of radiofrequency endovenous catheter, $VNUS^{\circledR}Colosure$ fast VNUS medical Technologies, San Jose, CA, adopted a segmental ablation system, instead of continous pullback, is designed to reduce treatment time in comparison with the previous model $VNUS^{\circledR}Colosure$ plus VNUS medical Technologies, San Jose, CA. The purpose of this study is to compare the difference between two endovenous radiofrequency ablation systems in terms of treatment efficacy and complication rates. We analyze the initial efficacy and complication rates of $VNUS^{\circledR}Colosure$ fast with $VNUS^{\circledR}Colosure$ plus. Material and Method: Between June 2006 and August 2009, $VNUS^{\circledR}Colosure$ plus was performed to treat varicose vein on 59 limbs in 41. patients and $VNUS^{\circledR}Colosure$ fast was performed on 76 limbs in 67 patients. We retrospectively compared in both group with sex, mean treatment time, mean treatment diameter, conjugated treatment, and complications after the procedure. Result: All patient were symptomatic and diagnosed as varicose vein and underwent level 2 clinical classification with color duplex scan. The mean treatment time for the great saphenous vein was significantly less with $VNUS^{\circledR}Colosure$ fast ($17.0{\pm}6.5min$) than $VNUS^{\circledR}Colosure$ plus ($62.7{\pm}9.8min$). There was no significant difference in 1 yr closure rate between groups (p=0.32). Minor complications such as skin burn, thrombophlebitis, ecchymosis, hematoma, cellulitis, tenderness, and there were not different between the groups. Conclusion: Both $VNUS^{\circledR}Colosure$ fast and $VNUS^{\circledR}Colosure$ plus are effective methods of endovenous saphenous ablation. $VNUS^{\circledR}Colosure$ fast is superior to the previous model with less treatment time preserving compatible efficacy and complications. The efficacy of $VNUS^{\circledR}Colosure$ fast for long term closure rate remains to be established.

• Korean Journal of Environment and Ecology
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• v.22 no.6
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• pp.679-690
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• 2008

The objectives of this study are to investigate and analyze the vegetation structure and population dynamics of Berchemia racemosa habitats in the Weolmyung park in Gunsan city, and base on that to seek the ecological habitat conservation plan for the Berchemia racemosa. In results, the Berchemia racemosa habitats are located at $81{\sim}93$ meters above the sea level, in steep seaside slope of a mountain. The soil texture are silt loam mainly and soil pH were $4.1{\sim}5$. The vascular plants in the Berchemia racemosa habitats has been analyzed as 61 taxa; 33 families, 51 genera, 54 species, 6 varieties, and 1 forms. Berchemia racemosa as a Specific plant species by floral region was the class V. Berchemia racemosa habitats were classified into 7 vegetation communities of Quercus serrata community(A1), Alnus firm a community(A2), Platycarya strobilacea community(A3), Robinia pseudoacacia community(A4) and 3 Pinus densiflora communities(B1, B2, B3). The importance value of Berchemia racemosa were 30%(A1), 15%(A2), 27%(A3), 65%(A4), 18%(B1), 45%(B2) and 35%(B3) on shrubs layer and 12, 27, 20, 18, 11, 18, 21 % on herb layer. The constant companion species with Berchemia racemosa were Stephanandra incisa and Ligustrum obtusifolium. Total 103 populations appear in the 7 Berchemia racemosa habitats. Their spatial distribution pattern were clumped for the most part. The average height was 133cm, the root color diameter was 4.4cm and the ramification branch number was 9.4. From the results of this study, it is suggested the continued monitoring and the active protection measures for the Berchemia racemosa habitats.