• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.504-515
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• 2021

To examine the relationship between environmental factors influencing the habitat of Aconitum austrokoreense Koidz., this study employed the MexEnt model to evaluate 21 environmental factors. Fourteen environmental factors having an AUC of at least 0.6 were found to be the age of stand, growing stock, altitude, topography, topographic wetness index, solar radiation, soil texture, mean temperature in January, mean temperature in April, mean annual temperature, mean rainfall in January, mean rainfall in August, and mean annual rainfall. Based on the response curves of the 14 descriptive factors, Aconitum austrokoreense Koidz. on the Baekun Mountain were deemed more suitable for sites at an altitude of 600 m or lower, and habitats were not significantly affected by the inclination angle. The preferred conditions were high stand density, sites close to valleys, and distribution in the northwestern direction. Under the five-age class system, the species were more likely to be observed for lower classes. The preferred solar radiation in this study was 1.2 MJ/m². The species were less likely to be observed when the topographic wetness index fell below the reference value of 4.5, and were more likely observed above 7.5 (reference of threshold). Soil analysis showed that Aconitum austrokoreense Koidz. was more likely to thrive in sandy loam than clay. Suitable conditions were a mean January temperature of - 4.4℃ to -2.5℃, mean April temperature of 8.8℃-10.0℃, and mean annual temperature of 9.6℃-11.0℃. Aconitum austrokoreense Koidz. was first observed in sites with a mean annual rainfall of 1,670- 1,720 mm, and a mean August rainfall of at least 350 mm. Therefore, sites with increasing rainfall of up to 390 mm were preferred. The area of potential habitats having distributive significance of 75% or higher was 202 ha, or 1.8% of the area covered in this study.

• Korean Journal of Breeding Science
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• v.42 no.4
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• pp.397-406
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• 2010

Field screening method has been commonly used for purity test of $F_1$ hybrid seeds in melon and oriental melon. However, as this method takes a lot of time and cost, molecular marker-based purity test is necessary. To develop molecular markers for purity test, thirty pairs of SNP (single nucleotide polymorphism) primers were obtained from melon EST sequences, and 10 polymorphic markers showing HRM (high resolution melting) polymorphisms between parents of two melon cultivars and one oriental melon cultivar were selected. Blind tests were performed to validate usefulness of the selected markers for purity test. Blind test results showed that HRM genotypes were matched with the expected identity of individual sample, $F_1$ hybrid, male or female parents. Three HRM-based SNP markers were converted to CAPS markers for general use which is favor to breeders. We expect that SNP markers developed in this study will be useful for purity test of $F_1$ hybrid seeds in melon and oriental melon.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.3
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• pp.60-70
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• 2019

Today, Deoksugung Doldam-gil, which is a well-known area in Seoul, has become a mixed place as many places reaching a critical age have been converted into parks. However, the previous research on the Deoksugung Doldam-gil was deficient in that the user, an essential variable, was not considered when assessing the place. Based on that, this study aims to analyze and interpret the perception of the places in Deoksugung Doldam-gil and to analyze factors to further enrich the place to visitors. According to the research, the representative idea of Deoksugung Doldam-gil is "the distance you want to go" and that has influencing factors, such as vehicle restrictions and the improvement of the walking environment. The analysis of classifying the variables that make up the perception of the place, physical environments, activities and meanings showed high awareness in, "streets of green (3.95)" and "stone walls of curves (3.88)." In the category of activities, "walking activities in the inner city (4.01)" and "love and romance (3.57)" were high. These results seem to reflect the spatial characteristics of the streets and the familiar image of the place were important. Five factors were extracted from the factor analysis to provide a more detailed understanding of the place perception, the correlation between each factor, and the place atmosphere of Deoksugung Doldam-gil. These factors confirmed a high correlation between 'green landscape' and 'historicity.' This can be attributed to the fact that the analysis reflects vital space, visual experience, and free walking conditions to be important, and these variables are present in urban parks. It also indicates the long-accumulated image and behavior near the site of Deoksugung Palace, including the historical and cultural heritage. It was confirmed that the factors related to the cognitive perception of Deoksugung Doldam-gil and the formation of the atmosphere of the place were strongly recognized. It found that there was a need to reflect the value and importance of 'green' in the future as culture or in the use of preservation and management related to heritage. This study presented a direction to be noted from the perspective of a user's place awareness, but considered only a fraction of the variables that affect the multidimensional sense of place and location recognition, and thus must be supplemented in the future.

• Korean Journal of Organic Agriculture
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• v.27 no.1
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• pp.33-44
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• 2019

This study was initiated to find possibility of substitute of gibberellin acid and to prevent negative girdling effect such as slow growth of 'Niitaka' (Pyrus pyrifolia Nakai) trees, a major pear cultivar, at harvest and at 60-, 90-, and 120-d after storage. Seasonal wiring with 3.0-mm-diameter were applied on the main branch at 70, 80, 90, 110, and 130 days after full bloom (DAF) to compare the fruit quality and storability. Fruit weight and sugar contents were the greatly increased by the wiring treatment at 110 DAF, with the lowest values observed for the wiring at 70 DAF. All the wiring treatments reduced fruit acidity but did not affect fruit firmness. a-value on fruit skin was the highest for wiring at 110 DAF and 130 DAF, advancing fruit ripening. The lowest fruit weight loss was occurred at wiring at 110 DAF. a-value on fruit skin was the highest for wiring at 90 DAF and 110 DAF. Wiring at 80 DAF the most increased floral bud diameter, resulting in the lowest L:D ratio of 1.74 observed. As for the mineral nutrients concentrations of floral buds, the concentration of K (0.63%) and Mg (0.31%) were the highest after 80 DAF wiring treatment, whereas Ca and P concentrations did not differ among treatment plots. The leaf K concentrations was the highest in the 130-day wiring treatment (0.76%) and in the control plot (0.78%), whereas there was no significant difference in the concentrations of either Ca or P among treatment plots. Short periods of wiring increased foliar Mg concentrations. In floral buds, carbohydrates showed a tendency for accumulating at a lower concentrations (7.75%) after 70 DAF wiring treatment, which was a relatively short treatment period. On the other hand, the carbohydrate concentrations in leaves showed a tendency for accumulating at lower concentrations after 130 DAF wiring treatment (2.51%), which is a long treatment period, and in the control plot (2.43%). Wiring increased the size and sugar content of fruits, and influenced fruit storability. For the wiring treatment period was delayed, the carbohydrate concentration in flower buds showed curvilinear correlation and the negative correlation with the carbohydrate in leaf tissue.

• Korean Journal of Clinical Laboratory Science
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• v.50 no.4
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• pp.449-456
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• 2018

Cervical cancer is the fourth most frequently diagnosed cancer in women worldwide. In lower Human Development Index countries, it has the second highest incidence and mortality among cancer in women. Therefore, better diagnosis and treatment systems are needed. Among them, estrogen receptor alpha ($ER-{\alpha}$) mRNA expression has been analyzed with RT-qPCR since several studies reported that $ER-{\alpha}$ is necessary in the maturation of the uterus and is related to cervical cancer. In this study, $ER-{\alpha}$ quantitative analysis was performed on various lesions and normal tissue samples. Based on the receiver operating characteristic (ROC) curve, its sensitivity and specificity were 85% and 75%, respectively, showing higher or similar results to those of conventional HPV tests. In addition, its expression level was analyzed with clinical information. With regression analysis, the R square value between the $ER-{\alpha}$ mRNA expression level and menopause status was 0.5041, indicating a strong correlation. This study was performed as part of a pilot study and suggests that $ER-{\alpha}$ is related to carcinogenesis. Future studies will examine other hormones and menopausal factors with a larger sample size.

• Journal of the korean academy of Pediatric Dentistry
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• v.48 no.4
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• pp.437-448
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• 2021

The purpose of this study is to analyze morphological characteristics of maxillary primary molar's root and root canal. 268 children aged 3 - 7 years (175 boys, 93 girls) who had CBCT (152 children) and 3D CT (116 children) taken in Seoul National University Dental Hospital from January 2006 to April 2020 were included. The number of roots and root canals were analyzed in 1002 teeth without any root resorption or periapical pathologies. Curvature, angulation, length of root and root canal, as well as cross-sectional shapes of the root canal were analyzed in 218 teeth. By using Mimics and 3-Matics software, volume, surface area, and volume ratio of root canal was analyzed in 48 teeth. More than half of maxillary primary molars have 3 roots and 3 root canals. The degree of symmetry of root canal type was about 0.63 (Cohen's kappa coefficient). The most frequent shape of roots and canals was linear in 1^st primary molars and curved in 2^nd primary molars. Angulation, length of root and root canals was the largest on palatal roots. Most teeth showed ovoid or round shapes at apex. The largest root canal volume, surface area, volume ratio was found in the palatal roots.

• Korean Journal of Culture and Social Issue
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• v.28 no.2
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• pp.187-217
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• 2022

The aim of this study is to examine the psychometric properties of the Korean version of the Post-traumatic Stress Disorder Checklist for DSM-5(PCL-5). For this purpose, online surveys were conducted for two times with a one year interval using the data from 1,077 Korean adults at time 1, and 563 Korean adults at time 2. First, from the result of the confirmatory factor analysis, comparing the model fit of the 1, 4, 6, and 7-factor model, the 4, 6, and 7-factor model showed a acceptable fit, and the best fit was seen in the order of the 7, 6, 4-factor model. Second, the internal consistency, omega coefficient, construct validity, average variance extracted, and test-retest reliability results were all satisfactory.. Third, a correlation analysis with the K-PC-PTSD-5 and the sub-factors of BSI-18 was conducted to check the validity of the Korean Version of PCL-5. As a result, a positive correlation was seen with both K-PC-PTSD-5 and BSI-18. Fourth, a hierarchical multiple regression was performed to examine whether the Korean Version of PCL-5 predicts future PTSD, depression, anxiety, and somatization. As a result, the Korean Version of PCL-5 measured at time 1 significantly predicted PTSD, depression, anxiety, and somatization symptoms at time 2. Fifth, by analyzing the ROC curve, the discriminant power of PCL-5 for screening PTSD symptom groups was confirmed, and the best cut-off score was suggested. As a result of the longitudinal validation of Korean version of PCL-5, it was found that this scale is a reliable and valid measure for Korean adults. By looking into the predictive validity of the scale, it was found that the Korean version of PCL-5 can predict not only PTSD symptoms but also PTSD-related symptoms such as depression, anxiety, and somatization. Also, this study differs from previous validation studies measuring PTSD symptoms in that it suggested a cut-off score to help differentiate PTSD symptom groups.

• Journal of the Korean Geotechnical Society
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• v.26 no.7
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• pp.117-133
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• 2010

A hybrid system of soil-nailing and compression anchor is proposed in this paper; the system is composed of an anchor bar (installed at the tip) with two PC strands and a steel bar. After drilling a hole, installing proposed hybrid systems, and filling the hole with grouting material, prestress is applied to the anchor bar to restrict the deformation at the head and/or to prevent shallow slope failures. However, since the elongation rate of PC strand is much larger than that of steel bar, yield at the steel bar will occur much earlier than at the PC strand. It means that the yield load of the hybrid system will be overestimated if we simply add yield loads of the two - anchor bar and PC strands. It might be needed to try to match the yielding time of the two materials by applying the prestress to the anchor bar. It means that the main purpose of applying prestress to the anchor bar should be two-fold: to restrict the deformation at the nail head; and more importantly, to maximize the design load of the hybrid system by utilizing load transfer mechanism that transfers the prestress applied at the tip to the head through anchor bar. In order to study the load transfer mechanism in a systematic way, in-situ pullout tests were performed with the following conditions: soil-nailing only; hybrid system with the variation of prestress stresses from 0 kN to 196 kN. It was found that the prestress applied to the anchor system will induce the compressive stress to the steel bar; it will result in decrease in the slope of load-displacement curve of the steel bar. Then, the elongation at which the steel bar will reach yield stress might become similar to that of PC strands. By taking advantage of prestress to match elongations at yield, the pullout design load of the hybrid system can be increased up to twice that of the soil-nailing system.

• Journal of Korean Tunnelling and Underground Space Association
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• v.11 no.1
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• pp.57-70
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• 2009

Considerable advance has been made on research on effect of steel pipe Umbrella Arch Method (UAM) and mechanical reinforcement mechanism through numerical analyses and experiments. Due to long analysis time of three-dimensional analysis and its complexity, un-quantitative two-dimensional analysis is dominantly used in the design and application, where equivalent material properties of UAM reinforced area and ground are used, For this reason, development of reasonable, theoretical, quantitative and easy to use design and analysis method is required. In this study, both field UAM tests and laboratory tests were performed in the residual soil to highly weathered rock; field tests to observe the range of reinforcement, and laboratory tests to investigate the change of material properties between prior to and after UAM reinforcement. It has been observed that the increase in material property of neighboring ground is negligible, and that only stiffness of steel pipe and cement column formed inside the steel pipe and the gap between steel pipe and borehole contributes to ground reinforcement. Based on these results and concept of Convergence Confinement Method (CCM), two dimensional axisymmetric analyses have been performed to obtain the longitudinal displacement profile (LDP) corresponding to arching effect of tunnel face, UAM effect and effect of supports. In addition, modified load distribution method in two dimensional plane-strain analysis has been suggested, in which effect of UAM is transformed to internal pressure and modified load distribution ratios are suggested. Comparison between the modified method and conventional method shows that larger displacement occur in the conventional method than that in the modified method although it may be different depending on ground condition, depth and size of tunnel, types of steel pipe and initial stress state. Consequently, it can be concluded that the effect of UAM as a beam in a longitudinal direction is not considered properly in the conventional method.

• Korean Journal of Remote Sensing
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• v.39 no.6_2
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• pp.1635-1650
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• 2023

Under global warming, the steadily increasing sea surface temperature (SST) severely impacts marine ecosystems,such as the productivity decrease and change in marine species distribution. Recently, the catch of Todarodes Pacificus, one of South Korea's primary marine resources, has dramatically decreased. In this study, we analyze the marine environment that affects the formation of fishing grounds of Todarodes Pacificus and develop seasonal habitat suitability index (HSI) models based on various satellite data including Geostationary Ocean Color Imager (GOCI) data to continuously manage fisheries resources over Korean exclusive economic zone. About 83% of catches are found within the range of SST of 14.11-26.16℃,sea level height of 0.56-0.82 m, chlorophyll-a concentration of 0.31-1.52 mg m^-3, and primary production of 580.96-1574.13 mg C m^-2 day^-1. The seasonal HSI models are developed using the Arithmetic Mean Model, which showed the best performance. Comparing the developed HSI value with the 2019 catch data, it is confirmed that the HSI model is valid because the fishing grounds are formed in different sea regions by season (East Sea in winter and Yellow Sea in summer) and the high HSI (> 0.6) concurrences to areas with the high catch. In addition, we identified the significant increasing trend in SST over study regions, which is highly related to the formation of fishing grounds of Todarodes Pacificus. We can expect the fishing grounds will be changed by accelerating ocean warming in the future. Continuous HSI monitoring is necessary to manage fisheries' spatial and temporal distribution.