• The Journal of Engineering Geology
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• v.18 no.3
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• pp.303-309
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• 2008

A probability of slope hazards was predicted at a natural terrain around the stone relics of Jinjeon-saji area, which is located in Yangyang, Kangwon Province. As the analyzing results of field investigation, laboratory test and geology and geomorphology data, the effect factors of landslides occurrence were evaluated. Also, the landslides prediction map was made up using the prediction model by the effect factors. The landslide susceptibility of stone relics was investigated as the grading classification of occurrence probability. In the landslides prediction map, the high probability area was $3,489m^2$ and it was 10.1% of total prediction area. The high probability area has over 70% of occurrence probability. If landslides are occurred at the predicted area, the three stories stone pagoda of Jinjeon-saji(National treasure No. 122) and the stone lantern of Jinjeon-saji(Treasure No.439) will be collapsed by debris flow.

• Safety and Health at Work
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• v.13 no.2
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• pp.227-234
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• 2022

Background and Purpose: In 2021, lung cancer in school food workers was first recognized as an occupational cancer. The classification of the carcinogenicity of cooking fumes by International Agency for Research on Cancer (IARC) was based on Chinese epidemiological data. This study aimed to determine the hazard levels of school cooking fumes in Korea. Materials and Methods: Based on public school cafeterias in one area, 25 locations were selected for the survey according to the number per school type, ventilation states, and environmental pre-assessments of cafeterias. Two inside cooking areas using a heat source and one outside cooking area were selected as control measurement points. Measurements of CO, CO₂, polycyclic aromatic hydrocarbons (PAHs), and total volatile organic compounds (TVOCs), including benzene, formaldehyde, and particulate matter (PM10, PM2.5, PM1, respectively), were taken. The concentrations and patterns of each substance in the kitchens were compared with the outdoor air quality. Result: Known carcinogens, such as the concentrations of PAHs, formaldehyde, TVOC (benzene), and particulate matter in school cooking fumes, were all detected at similar or slightly higher levels than those found outside. Additionally, substances were detected at relatively low concentrations compared to the Chinese cooking fumes reported in the literature. However, the short-term exposure to high concentrations of CO (or composite exposure with CO₂) and PM2.5 in this study were shown. Conclusion: The school cooking fumes in South Korea was a relatively less harmful than Chinese cooking fumes, however short-term, high exposure of toxic substances can cause a critical health effect.

• Journal of Korean Society of Disaster and Security
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• v.14 no.3
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• pp.17-27
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• 2021

In this study, classification models were built using machine learning techniques that can classify the soil creep risk into three classes from A to C (A: risk, B: moderate, C: good). A total of six machine learning techniques were used: K-Nearest Neighbor, Support Vector Machine, Logistic Regression, Decision Tree, Random Forest, and Extreme Gradient Boosting and then their classification accuracy was analyzed using the nationwide soil creep field survey data in 2019 and 2020. As a result of classification accuracy analysis, all six methods showed excellent accuracy of 0.9 or more. The methods where numerical data were applied for data training showed better performance than the methods based on character data of field survey evaluation table. Moreover, the methods learned with the data group (R1~R4) reflecting the expert opinion had higher accuracy than the field survey evaluation score data group (C1~C4). The machine learning can be used as a tool for prediction of soil creep if high-quality data are continuously secured and updated in the future.

• Journal of the Korean Institute of Gas
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• v.22 no.4
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• pp.13-26
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• 2018

Currently, local regulations, such as KS Code, do not clearly specify how to calculate the range of hazardous area, so the dispersion modeling program should be used to select dispersion. The purpose of this study is to present a methodology of determining the range of hazardous area which is simpler and more reasonable than modelling by using representative materials and process conditions. Based on domestic and overseas regulations that are currently in effect, variables affecting distance to LFL(Lower Flammable Limit) were selected. A total of 16 flammable substances were modelled for substance variables, process conditions variables, and weather conditions variables, and the statistical analysis selected the variables that affect them. Using the selected variables, a three-step classification method was prepared to select the range of locations subject to explosion hazard.

• Clinical and Experimental Pediatrics
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• v.64 no.9
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• pp.480-488
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• 2021

Background: An adequate large-scale pediatric cohort based on nationwide administrative data is lacking in Korea. Purpose: This study established the National Investigation of Birth Cohort in Korea study 2008 (NICKs-2008) based on data from a nationwide population-based health screening program and data on healthcare utilization for children. Methods: The NICKs-2008 study consisted of the Korean National Health Insurance System (NHIS) and the National Health Screening Program for Infants and Children (NHSPIC) databases comprising children born in 2008 (n=469,248) and 2009 (n=448,459) in the Republic of Korea. The NHIS database contains data on age, sex, residential area, income, healthcare utilization (International Classification of Diseases10 codes, procedure codes, and drug classification codes), and healthcare providers. The NHSPIC consists of 7 screening rounds. These screening sessions comprised physical examination, developmental screening (rounds 2-7), a general health questionnaire, and age-specific anticipatory guidance. Results: During the 10-year follow-up, 2,718 children (0.3%) died, including more boys than girls (hazard ratio, 1.145; P<0.001). A total of 848,048 children participated in at least 1 of the 7 rounds of the NHSPIC, while 96,046 participated in all 7 screening programs. A total of 823 infants (0.1%) weighed less than 1,000 g, 3,177 (0.4%) weighed 1,000-1,499 g, 37,166 (4.4%) weighed 1,500-2,499 g, 773,081 (91.4%) weighed 2,500-4,000 g, and 32,016 (5.1%) weighed over 4,000 g. There were 23,404 premature babies (5.5%) in 2008 compared to 23,368 (5.6%) in 2009. The developmental screening test indicated appropriate development in 95%-98% of children, follow-up requirements for 1%-4% of children, and recommendations for further evaluation for 1% of children. Conclusion: The NICKs-2008, which integrates data from the NHIS and NHSPIC databases, can be used to analyze disease onset prior to hospitalization based on information such as lifestyle, eating habits, and risk factors.

• Journal of the Korean Society of Hazard Mitigation
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• v.1 no.2 s.2
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• pp.123-137
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• 2001

Based on basic characteristics of urban disasters and their data availabilities in Korea, this study provides risk assessment models which are derived from Cheongju examples. In specific, the application models are confined to fire, facility and escape risk survey results in the paper. For the assessment criteria, major independent variables for the categories of fire include both the frequency levels and the amount of damage. And the degree of facility risk assessment is heavily hinged on both the weighted values of key facilities and their weighted rank-sizes. In the same context, the degree of escape risk assessment is hinged on both the weighted values and the amount of the classification of land. From the empirical configuration, this paper presents that the potential figure of fire risk is relatively higher in the built-up areas within the existing Central Business District where accommodates a number of dilapidated housing units and community-supportive facilities. In contrast, the potential figure of facility and escape risk is higher in both old residential areas and the newly-built apartment complex. In short, the CBD and its neighboring residential areas record a high potential figure in terms of total risk, juxtaposing fire, facility and escape risk all together.

• Analytical Science and Technology
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• v.23 no.4
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• pp.423-428
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• 2010

In this study, VOCs of black gel pen inks was screening to identify individual characteristic of gel pen inks. Detected VOCs was total 20 species(isopropylalcohol, 2-methyl-2-propanol, 2-butanone, hydrazinecarbothioamide, benzeneacetic acid (ethyl ester), benzeneacetic acid, dimethoxymethy-silane, 2,2-dimethoxybutane, tetrahydro-2-methyl-furan, 1,2-ethanediol, silicic acid (tetramethyl ester), 1,2-propanediol, propyleneglycol, 3-ethyl-3-hexanol, 1,1-dipropoxy-propane, 2-butoxy-ethanol, 2,2'-oxybisethanol, 1-butyl-benzene, 2-pyrrolidinone, 2-(2-butoxyethoxy)-ethanol). We detected 2,2-dimethoxybutane (3.02~47% ratio) and tetrahydro-2-methyl-furan (1.19~52.19% ratio), 1,2-ethanediol (52.83~95.84% ratio). In case of manufacturer, manufactured ink was able to discriminate between Japan and Korea by distinct characteristics (Japan: 1,2-ethanediol, 52.83~95.84%, Korea: 1,2-propanediol, 76.17~93.51%). The results of this study indicated that distinct characteristic about manufacturers and brands could make a classifring tool of inks for identification of between gel pen inks.

• Tuberculosis and Respiratory Diseases
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• v.80 no.2
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• pp.179-186
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• 2017

Background: Although the World Health Organization (WHO) classification of lung squamous cell carcinoma (SCC) was revised in 2015, its clinical implications for lung SCC subsets remain unclear. We investigated whether the morphologic characteristics of lung SCC, including keratinization, were associated with clinical parameters and clinical outcome of patients. Methods: A total of 81 patients who underwent curative surgical resection of diagnosed lung SCC, were enrolled in this study. Attributes such as keratinization, tumor budding, single cell invasion, and nuclear size within the tumor, as well as immunohistochemistry of Bcl-xL and pS6 expressions, were evaluated. Results: The keratinizing and nonkeratinizing subtypes did not differ with respect to age, sex, TNM stage, and morphologic parameters such as nuclear diameter, tumor budding, and single cell invasion at the tumor edge. Most patients with the keratinizing subtype (98.0%) had a history of smoking, whereas the nonkeratinizing group had a relatively higher proportion of never-smokers relative to the keratinizing group (24.0% vs. 2.0%; p=0.008, chi-square test). Expression of pS6 (a surrogate marker of mammalian target of rapamycin complex 1 [mTORC1] signaling that regulates keratinocyte differentiation), and Bcl-xL (a key anti-apoptotic molecule that may inhibit keratinization), did not correlate significantly with the presence of keratinization. Patients with the keratinizing subtype had a significantly shorter overall survival (85.2 months vs. 135.7 months, p=0.010, log-rank test), and a multivariate analysis showed that keratinization was an independent, poor prognostic factor (hazard ratio, 2.389; 95% confidence interval, 1.090-5.233; p=0.030). Conclusion: In lung SCC, keratinization is associated with a poor prognosis, and might be associated with smoking.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.6
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• pp.845-852
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• 2014

The quality of commercial sauce products was evaluated through pH, soluble solid content, salinity, water activity and microbial analyses. The pH of sauces was 2.38~5.30, soluble solids were between 6.03 and 71.67, and distributions of salt were 0.23~5.00% in 32 commercial sauce products. In addition, water activity of vinegar red pepper sauce and spicy soft tofu stew stock were determined 0.773 and 0.988, respectively. Yeast, mold, Staphylococcus aureus, E. coli and coliform were not detected in any sauces. Higher level of total viable cells (TVC) resulted in pH over 4.2. TVC of shelf-stable sauces was 1.0~3.6 log CFU/g. TVC of seven sauce products was classified as non-potentially hazardous foods by temperature controlled for safety standard (TCS), even though levels were over acceptable guidelines of the USDA (3 log CFU/g). These results indicate that the standard and classification of commercial sauce products should be modified and controlled strictly.

• Journal of Yeungnam Medical Science
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• v.40 no.1
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• pp.65-77
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• 2023

Background: This study aimed to compare clinical outcomes between surveillance and adjuvant therapy (AT) groups after R0 resection for cholangiocarcinoma (CCA). Methods: A total of 154 patients who underwent R0 resection for CCA at the Daegu Catholic University Medical Center between January 2010 and December 2019 were included. Overall survival (OS) and progression-free survival (PFS) were analyzed. Results: The median follow-up duration was 899 days. There were 109 patients in the AT group and 45 patients in the surveillance group. The patients in the AT group were younger (67 years vs. 74 years, p<0.001) and included more males (64.2% vs. 46.7%, p=0.044). The proportion of patients with stage III CCA was larger in the AT group than in the surveillance group (13.8% vs. 2.2%, p=0.005). In addition, AT did not improve OS (5-year OS rate, 69.3% in the AT group vs. 64.2% in the surveillance group, p=0.806) or PFS (5-year PFS rate, 42.6% in the AT group vs. 48.9% in the surveillance group, p=0.113). In multivariate analysis using the Cox proportional hazards model, stage III CCA (hazard ratio [HR], 10.81; 95% confidence interval [CI], 2.92-40.00; p<0.001) was a significant predictor of OS. American Society of Anesthesiologists classification II (HR, 0.50; 95% CI, 0.31-0.81; p=0.005), and American Joint Committee on Cancer stages II (HR, 3.14; 95% CI, 1.25-7.89; p=0.015) and III (HR, 8.08; 95% CI, 2.80-23.32; p<0.001) were independent predictors of PFS. Conclusion: AT after R0 resection for CCA did not improve OS or PFS.