• Journal of Korea Water Resources Association
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• v.40 no.6 s.179
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• pp.469-483
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• 2007

Nitrate and chloride are the most common contaminants in groundwater and their concentrations increase easily due to fertilizer consumption and urbanization. The number of time series data for groundwater quality at a single site was not sufficient to analyze trends on Jeju Island. Therefore rectangle grids were drawn for the whole island and single grid was determined to be $500m{\times}500m$ after considering similar stream density, homogeneous hydraulic coefficients, geologic features of volcanic rock and low topographic slopes. All data within each lattice were collected and arranged in time series order and analyzed using Sen's method. 10.6 % of the total lattices for chloride and 22.4% for nitrate showed upward trends from the early 1990's to the early 2000's. Especially, upward trends for nitrate concentration are distinct in the low mid-mountainous areas of western and southern watersheds. Many septic tanks and much domestic waste from the urbanization of the low mid-mountainous area have produced this upward trend. Additionally, the agricultural region has dramatically increased since the 1990's and this has led to an increase of fertilizer consumption and, as a result, nitrate concentration. Therefore, the target of any management plan for groundwater quality on Jeiu Island needs to be focused on careful land use decisions in the mid-mountainous areas which are near Halla Mountain.

• Journal of Korean Society of Forest Science
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• v.101 no.1
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• pp.28-35
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• 2012

Rainfall is widely recognized as a major landslide-triggering factor. Most of the latest landslides that occurred in South Korea were caused by short-duration heavy rainfall. However, the relationship between rainfall characteristics and landslide occurrence is poorly understood. To examine the effect of rainfall on landslide occurrence, cumulative rainfall(mm) and rainfall intensity(mm/hr) of serial rain and antecedent rainfall(mm) were analyzed for 18 landslide events that occurred in the southern and central regions of South Korea in June and July 2011. It was found that all of these landslides occurred by heavy rainfall for one or three days, with the rainfall intensity exceeding 30 mm/hr or with a cumulative rainfall of 200 mm. These plotted data are beyond the landslide warning criteria of Korea Forest Service and the critical line of landslide occurrence for Gyeongnam Province. It was also found that the time to landslide occurrence after rainfall start(T) was shortened with the increasing average rainfall intensity(ARI), showing an exponential-decay curve, and this relation can be expressed as "T = $94.569{\cdot}exp$($-0.068{\cdot}ARI$)($R^2$=0.64, p<0.001)". The findings in this study may provide important evidences for the landslide forecasting guidance service of Korea Forest Service as well as essential data for the establishment of non-structural measures such as a warning and evacuation system in the face of sediment disasters.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.6987-6990
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• 2015

Background: Oral cancer is one of the most prevalent cancers and one of the top ten causes of death in the whole world. Most oral cancers are diagnosed at late stages. Since dentists play a critical role in early detection of oral cancer, they should be knowledgeable and skillful in oral cancer diagnosis. The aim of this study was to survey dentist knowledge about oral cancer in Southern Khorasan Province. Materials and Methods: This descriptive, cross-sectional study was conducted with dentists who participated in an in-service educational program at the Faculty of Dentistry of Birjand University of Medical Sciences in spring 2014. A questionnaire including demographic information with 11 questions regarding oral cancer was prepared. The participants were required to be complete the questionnaires within a specific time span. The data were analyzed using SPSS 15 software by t-test and one-way ANOVA at 0.05 confidence level. Results: A total of 73 dentists out of 80 answered the questionnaires - 36 (49.3%) were females and 37 (50.7%) were males. Total mean score of knowledge was $7.91{\pm}1$ of 11. Mean scores of knowledge of male and female participants were $7.70{\pm}1.83$ and $8.13{\pm}1.94$ respectively. Mean knowledge score of general dentists was $7.41{\pm}1.79$ and of dental specialists was $9.44{\pm}1.0$ In spite of higher knowledge score of women compared to men and general dentists compared to dental specialists, these differences were not statistically significant (p=0.09). Tukey testing showed a significant difference between groups with 1-4 years of experience (8.74) and over twenty years of experience (6.50) ( p=0.001). Conclusions: Considering the good knowledge level of young dentists and the specialists and the importance of early diagnosis of oral cancer, it seems necessary to pay more attention to academic education for dentistry students, as well as holding retraining courses for experienced dentists, so that their knowledge not be reduced over time.

• Korean Journal of Plant Taxonomy
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• v.45 no.1
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• pp.72-95
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• 2015

In order to illustrate the flora of vascular plants distributed in the area of Mt. Hambaek-san and its neighboring mountains, the authors collected vascular plants intensively on Mt. Hambaek-san (1,573 m), Mt. Geumdae-bong (1,418 m) and Mt. Daedeok-san (1,307 m) from April of 2012 to August of 2014. All of them consisted of 90 families, 310 genera, 532 species, 4 subspecies, 73 varieties and 13 forms, with a total of 622 taxa. The total number of vascular plants in the investigated area was 808 taxa (17.55% of all vascular plants in Korea) with the addition of voucher specimens from previous investigations. Among the collected plants, endemic ones were 21 taxa, rare and endangered ones 26 taxa, naturalized ones 30 taxa, useful ones 464 taxa, and floristically specific ones of Korean floristic zones 62 taxa except for species of the first and second grade. Among the floristic zones of the Korean Peninsula, this investigated area showed the typical vegetation of a temperate middle province into which more northern elements than southern elements flowed.

• Journal of Environmental Impact Assessment
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• v.27 no.6
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• pp.521-547
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• 2018

To provide fundamental information to areas that lack data on the plant resources and the ecosystem, this study conducted a survey on the vascular plants in Mt. Jigisan in Hongseonggun. The vascular plants identified during the six-round field surveys were a total of 443 taxa: 96 families, 286 genera, 391 species, 7 subspecies, 40 varieties, 3 forms, and 2 hybrids. On floristic regional of Korea, Mt. Jigisan is deciduous broad-leaved and conifer-mixed forest which is south province of Korean peninsula. 4 taxa of Korean endemic plants such as Populus ${\times}$ tomentiglandulosa, Forsytsythia koreana, Forsytsythia ovate, and Iris rossii var. latifolia were collected. The vascular plants on the red list according to IUCN evaluation basis were found to be 6 taxa: Vulnerable (VU) species of Forsytsythia ovata, Least Conern (LC) species of Chionanthus retusus, Pseudoraphis ukishiba, and Cymbidium goeringii, and Not Evaluate (NE) species of Panax ginseng, and Fimbristylis verrucifera. The floristic regional indicator plants were found 27 taxa: 2 taxa of grade V, 3 taxa of grade IV, 6 taxa of grade III, 4 taxa of grade II, and 12 taxa of grade I. The specific distribution plants were found 27 taxa: 4 taxa of northern part of plants, 12 taxa of southern part of plants, 10 taxa of isolation distribution of plants, and 1 taxon of recently reported Viola betonicifolia var. albescens. The invasive alien plants were identified as 67 taxa. The naturalized index (NI) was 15.12%, and urbanization index (UI) was 20.9%, respectively.

• Journal of Bio-Environment Control
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• v.32 no.4
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• pp.336-341
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• 2023

This study examines the characteristics of berries from secondary bearing shoots of 'Scintilla' southern highbush blueberry, grown hydroponically in the Jinju, Gimhae, and Uiryeong regions of Gyeongnam Province. Typically, 'Scintilla' forms flower buds at the tips of regular bearing shoots during the previous season, yielding berries in the current season. However, under heated cultivation, we observed a proliferation of secondary bearing shoots that produce berries in the same growing season. Flowering and harvesting on secondary bearing shoots were delayed by 52 and 36 days, respectively, compared to regular bearing shoots. However, these shoots exhibited a 54% increase in diameter and a 10% increase in length. We found no significant difference in berry size and soluble solid content between the two types of shoots. Notably, berries from the secondary bearing shoots had higher potassium and lower calcium and magnesium concentrations. We conclude that berries from secondary bearing shoots could be marketable, provided the bushes are healthy. These findings provide valuable insights for optimizing cultural practices to improve the yield and quality of blueberries under specific environmental conditions.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.3
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• pp.208-214
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• 2016

This study was conducted to evaluate the effects of different sowing times (May 25, June 10, June 25, July 10, and July 25) on growth and yield of four proso millet (Panicum miliaceum L.) cultivars (Hwanggeumkijang, Manghongchal, Ibaekchal, and Hwangsilchal) at a cultivation area in Iksan, Jeonbuk Province. Heading and ripening times were delayed, with later sowing times in all cultivars, and the periods for heading and ripening were shortened. For sowing from May 25 to July 25, the growth stage was shorter by 40 days in Manghongchal, 38 days in Hwanggeumkijang, 36 days in Hwangsilchal, and 30 days in Ibaekchal. The culm length, ear length, ear width, and culm diameter differed significantly between the cultivars and sowing times. In particular, the culm and ear lengths were considerably reduced when the sowing time was delayed. The grain yield (kg/10a) of Hwanggeumkijang and Ibaekchal was 312 and 359 kg, respectively, for sowing on June 10; and that of Manhongchal and Hwangsilchal was 286 and 404 kg, respectively, for sowing on June 25. Thus, the optimum sowing time was June 25 for Hwanggeumkijang and Ibaekchal, and June 10 for Manhongchal and Hwangsilchal.

• Journal of the Mineralogical Society of Korea
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• v.31 no.2
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• pp.123-135
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• 2018

This study tried to find the clue to Seokrok province by comparing Seokrok used in painting culture properties with Seokrok ore from domestic occurrence and imported Seokrok ore. To this end, chemical and mineralogical characteristics of painting cultural properties were identified with portable X-ray Florescence (p-XRF), micro X-ray diffraction (micro XRD) and SEM/EDS Analysis. To obtain Pb isotopic ratio, the Pb contained in Seokrok has been analyzed with Thermal Ionization Mass Spectrometer. Atacamite (or botallackite) and small quantity of brochantite were identified from Seokrok in Dancheong, and malachite was also identified from Buddhist painting besides those two ingredients. Without distinction of type, most Seokrok used in painting cultural properties is atacamite composed of Cu and Cl. From Pb isotope analysis, it was found that Seokrok in painting cultural properties was closer to that of north Korea, north China and Japan than south Korea as in regional division for East North Asia suggested by Mabuchi. The Pb isotopic ratio of domestic green mineral belongs to the distribution of Seokrok inside the painting cultural properties but imported malachite showed considerably difference. Considering the fact that atacamite, the main mineral of Seokrok in painting cultural properties is rarely produced from southern mine of the Korean Peninsula and the result of Pb isotope analysis.

• Industry Promotion Research
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• v.8 no.4
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• pp.69-79
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• 2023

This study sought to propose ways to improve the happiness of Chinese product designers by verifying whether grit moderates the effect of job stress on happiness through professional values. A purposively sampled participants of 335 Chinese product designers living in Guangdong Province, southern China, were selected. Data analysis was performed using SPSS PC+ Win. Ver. 26.0 and PROCESS Macro ver. 4.2. The statistical techniques applied were frequency analysis, reliability analysis, correlation analysis, and moderated mediation effect analysis. The research results are as follows. First, job stress showed a negative correlation with professional value and grit, but did not show a significant correlation with happiness. Except for job stress, there was a positive significant correlation between other variables. Second, the conditional indirect effect was significant when grit was M-SD, M, or M+SD. M+SD. Therefore, the moderated mediating role of grit was verified. However, as professional value increased, grit played a role in increasing happiness. Still, in the path of job stress -> professional value -> happiness, grit did not buffer the negative effect of job stress on happiness through professional stress. Suggestions were made to improve the happiness of product designers using professional values and grit.

• Korean Journal of Environmental Agriculture
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• v.18 no.2
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• pp.169-173
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• 1999

To investigate the chemical properties of rainwater in the southern part of gyeonggi Province, the rainwater was collected in Suwon and Ansung for six months from May to October in 1998, and analyzed its chemical composition. The ion balance and electric conductivity balance showed confidence to chemical analyses of rainwater. The most frequent pH range of rainwater was pH $5.0{\sim}5.6$ both in Suwon and Ansung area with distribution ratio of 37.9% and 35.3%, respectively. Among the 1mm fraction for initial 5mm of rainfall, ion concentration of initial rainwater (less than 1mm of rainfall) was higher than those of the later terms. The major ions in rainwater were $NH_4^-,\;Ca^{2+}$and $Na^+$ for cations, and $SO_4^{2-}$ and $NO_3^-$ for anions. Monthly variation of pH of rainwater showed low level of 4.2 to 4.5 in Suwon and 4.6 to 4.7 in Ansung in August and September, respectively. The $nss-SO_4^{2-}/NO_3^-$ ratio of rainwater in Suwon and Ansung area were 2.2 and 2.9 which means nonsea salt $SO_4^{2-}$ contrbuted to acidity of rainwater more in Ansung than Suwon area.