• Korean Journal of Remote Sensing
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• v.38 no.6_1
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• pp.1479-1488
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• 2022

Accidents in which oil spills occur intermittently in the ocean due to ship collisions and sinkings. In order to prepare prompt countermeasures when such an accident occurs, it is necessary to accurately identify the current status of spilled oil. To this end, the Coast Guard patrols the target area with a fixed-wing airplane or helicopter and checks it with the naked eye or video, but it was difficult to determine the area contaminated by the spilled oil and its exact location on the map. Accordingly, this study develops a technology for direct ortho-rectification by automatically geo-referencing aerial images collected by the Coast Guard without individual ground reference points to identify the current status of spilled oil. First, meta information required for georeferencing is extracted from a visualized screen of sensor information such as video by optical character recognition (OCR). Based on the extracted information, the external orientation parameters of the image are determined. Images are individually orthorectified using the determined the external orientation parameters. The accuracy of individual orthoimages generated through this method was evaluated to be about tens of meters up to 100 m. The accuracy level was reasonably acceptable considering the inherent errors of the position and attitude sensors, the inaccuracies in the internal orientation parameters such as camera focal length, without using no ground control points. It is judged to be an appropriate level for identifying the current status of spilled oil contaminated areas in the sea. In the future, if real-time transmission of images captured during flight becomes possible, individual orthoimages can be generated in real time through the proposed individual orthorectification technology. Based on this, it can be effectively used to quickly identify the current status of spilled oil contamination and establish countermeasures.

• Korean Journal of Remote Sensing
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• v.37 no.2
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• pp.257-274
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• 2021

Although image segmentation is a critical part of object-based analysis of high resolution imagery, there has been lack of studies to evaluate the quality of image segmentation. In this study, we aimed to find practical and effective methods to obtain optimal parameters for image segmentation. Evaluations of image segmentation are divided into unsupervised, supervised, and qualitative visual interpretation methods. Using the multispectral UAV images, sampled from urban and forest over the Incheon Metropolitan City Park, three evaluation methods were compared. In overall, three methods showed very similar results regardless of the computational costs and applicability, although the optimal parameters determined by the evaluations were different between the urban and forest images. There is no single measure that outperforms in the unsupervised evaluation. Any combinations of intra-segment measures (V, COV, WV) and inter-segment measures (MI, BSH, DTNP) provided almost the same results. Although supervised method may be biased by subjective selection of reference data, it can be easily applied to detect object of interest. The qualitative visual interpretation on the segmentation results corresponded with the unsupervised and supervised evaluations.

• The Journal of the Korea Contents Association
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• v.21 no.11
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• pp.490-502
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• 2021

Horticultural facility farmers subscribe to crop accident insurance and insurance products secured by horticultural facilities in preparation for possible risks in the facility. Insurance is purchased to prepare for natural disasters such as typhoons, hail, frostbite, heavy rain, and strong wind damage covered by the product. In order to find out the effect of risk perception, which is a subjective perception of the risks of a given situation, on horticultural facility farmers' intention to purchase horticultural facility insurance products, the risk perception and insurance purchase intention were analyzed. A t-test was conducted to determine the impact relationship between farm size, insurance coverage, and risk perception, and multiple regression analysis was conducted to verify the effect of personal characteristics and behavioral factors such as subjective perception, reference group, media exposure, and compensation understanding. In addition, a three-step regression analysis by Baron & Kenny was conducted to confirm the mediating role of personal characteristics and behavioral factors in the relationship between risk perception and insurance purchase intention. As a result of the study, although there was no difference in farm size, it was analyzed that policy holders had a higher degree of risk perception than non-subscribers, and that compensation understanding had the greatest influence and subjective knowledge had the smallest influence. In addition, these four factors were verified to have a mediating effect on the relationship between risk perception and insurance purchase intention. These results are expected to provide practical help to the development and marketing activities of horticultural facility insurance products.

• Korean Journal of Community Nutrition
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• v.26 no.6
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• pp.467-481
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• 2021

Objectives: The purpose of this study was to examine the biochemical characteristics, intake of energy, and nutrients by household income levels of Korean adolescents aged 12 to 18 years. Methods: Data from the 6th (2013 ~ 2015) Korea National Health and Nutrition Examination Survey (KNHNES) were used for the study. A total of 1,839 (966 boys, 873 girls) subjects were included, and they were divided into four income groups according to their household income level. We examined general characteristics (gender, region of residence, skipping or not-skipping breakfast, lunch, dinner, frequency of eating-out), anthropometric characteristics (height, weight, weight status), biochemical characteristics (fasting plasma glucose, blood urea nitrogen, creatinine, triglycerides, cholesterol, HDL-cholesterol, hemoglobin, and hematocrit), the quantitative intake of energy and nutrients using the Korean Dietary Reference Intakes (KDRI), and the qualitative intake evaluated by the nutrition adequacy ratio (NAR) and mean nutrition adequacy ratio (MAR) of the four groups. Results: There were significant differences by income group within the region of residence and the rate of skipping breakfast, lunch, and dinner. The low-income group had a higher rate of skipping breakfast, lunch, and dinner. According to the income group, there was a difference in the height of boys, and there was no difference in the weight and obesity of boys and girls. In the biochemical characteristics, only the hematocrit of girls showed differences by income group. The quantitative intake of energy and nutrients compared with KDRI differed by income group. There were differences in energy, carbohydrates, proteins, thiamin, riboflavin, niacin, and phosphorus levels in boys and protein, vitamin A, niacin, and sodium levels in girls. The qualitative intake of energy and nutrients examined using NAR and MAR also differed according to the income group. The NAR showed differences in calcium in boys and vitamin C and calcium in girls. The MAR revealed differences in both boys and girls by income group. Conclusions: Among adolescents in the low-income group, the rate of skipping meals was high, and the quantitative and qualitative intake of energy and some nutrients was low. It is suggested that the nutritional intake can be improved by lowering the rate of skipping breakfast, lunch, dinner. We suggest that even just providing breakfast in schools can be considered highly effective in improving the rate of avoidance of skipping meals and improving nutrient intake. Also, we suggest that it is necessary to improve the food environment, food availability, and food accessibility through national and social support for low-household income adolescents.

• Korean Journal of Remote Sensing
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• v.38 no.3
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• pp.311-326
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• 2022

The Compact Advanced Satellite 500-4 (CAS500-4) is under development to efficiently manage and monitor forests in Korea and is scheduled to launch in 2025. The National Institute of Forest Science is developing 36 types of forestry applications to utilize the CAS500-4 efficiently. The products derived using the remote sensing method require validation with ground reference data, and the quality monitoring results for the products must be continuously reported. Due to it being the first time developing the national forestry satellite, there is no official calibration and validation site for forestry products in Korea. Accordingly, the author designed a calibration and validation site for the forestry products following international standards. In addition, to install calibration and validation sites nationwide, the authors selected appropriate sensors and evaluated the applicability of the sensors. As a result, the difference between the ground observation data and the Sentinel-2 image was observed to be within ±5%, confirming that the sensor could be used for nationwide expansion.

• Pediatric Infection and Vaccine
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• v.29 no.2
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• pp.70-76
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• 2022

Coronavirus disease 2019 (COVID-19) in patients with underlying diseases, is associated with high infection and mortality rates, which may result in acute respiratory distress syndrome and death. Mucopolysaccharidosis (MPS) type II is a progressive metabolic disorder that stems from cellular accumulation of the glycosaminoglycans, heparan, and dermatan sulfate. Upper and lower airway obstruction and restrictive pulmonary diseases are common complaints of patients with MPS, and respiratory infections of bacterial or viral origin could result in fatal outcomes. We report a case of COVID-19 in a 16-year-old adolescent with MPS type II, who had been treated with idursulfase since 5 years of age. Prior to infection, the patient's clinical history included developmental delays, abdominal distension, snoring, and facial dysmorphism. His primary complaints at the time of admission included rhinorrhea, cough, and sputum without fever or increased oxygen demand. His heart rate, respiratory rate, and oxygen saturation were within the normal biological reference intervals, and chest radiography revealed no signs of pneumonia. Consequently, supportive therapy and quarantine were recommended. The patient experienced an uneventful course of COVID-19 despite underlying MPS type II, which may be the result of an unfavorable host cell environment and changes in expression patterns of proteins involved in interactions with viral proteins. Moreover, elevated serum heparan sulfate in patients with MPS may compete with cell surface heparan sulfate, which is essential for successful interaction between the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein and the host cell surface, thereby protecting against intracellular penetration by SARS-CoV-2.

• The Journal of Korean Medicine
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• v.42 no.3
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• pp.26-43
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• 2021

Objectives: This study is designed to statistically analyze data of outpatients visiting for recent 3 years. The purpose is to identify tendencies of patients who visit the hospitals before and after COVID-19. Methods: This study retrospectively analyzed the medical records of 452,487 patients who visited to the Daejeon·Cheonan·Cheongju Korean Medicine Hospital of Daejeon University from January 1, 2018 to August 31, 2020. The data is classified according to year, month, gender, age, and visit type. The statistical analysis was performed using IBM SPSS 25.0. Results: The total number of patients decreased in 2020 compared to before 2020, and the number of patients in each hospital also decreased from the previous year. According to the year of each hospital, the difference by year was not statistically significant at Daejeon Hospital, but Cheonan and Cheongju Hospital showed statistical difference. The change in monthly according to the year by hospital has continued to decrease from January to March in 2020, unlike the previous year, which recovered from a decline in March. In the analysis of patients by age, there was no statistically significant difference in the number of patients in the above 60s according to the year, while those under 60s have a tendency to significantly decrease. Conclusion: We expect that the results of this study will be used as reference materials in analyzing effects of COVID-19 at health care utilization.

• The Journal of Advanced Prosthodontics
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• v.14 no.1
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• pp.1-11
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• 2022

PURPOSE. The maximum width between the mesial and distal labial transitional line angles, described as "esthetic width" herein, could significantly influence the visual perception of the teeth and smile. This study aimed to conduct biometric research on esthetic width and to explore whether regular distribution exists in the esthetic width of human teeth. MATERIALS AND METHODS. A total of 4,264 maxillary and mandibular anterior teeth were measured using the Geomagic studio software program. The proportions of maxillary to mandibular homonymous teeth and proportions between the adjacent teeth were calculated. Bilateral symmetry and the correlation between the esthetic and mesiodistal widths were both accounted for during the measurement procedures. RESULTS. The mean esthetic widths were 6.773 ± 0.518 mm and 4.329 ± 0.331 mm for maxillary and mandibular central incisors, respectively, 5.451 ± 0.487 mm and 5.008 ± 0.351 mm for maxillary and mandibular lateral incisors, respectively, and 3.340 ± 0.353 mm and 5.958 ± 0.415 mm for maxillary and mandibular canines, respectively. Except for the mandibular canines, no significant difference in esthetic width was found among homonymous teeth from the same jaw. A high linear correlation was found between the esthetic and mesiodistal widths of the same tooth, except for the maxillary canines. Esthetic width proportions among different tooth categories showed some regular patterns, which were similar to those of the mesiodistal width. CONCLUSION. Esthetic width is regularly distributed among the teeth in the Chinese population. This could provide an important reference for anterior dental restorations and dimension recovery in esthetic reconstruction of anterior teeth.

• Journal of Digital Convergence
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• v.20 no.5
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• pp.919-929
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• 2022

As a new type of healthy public space, greenway users carry out leisure activities, exercise, sightseeing and necessary transportation in greenway. However, at present, there is little research on greenway users' evaluation and perception of greenway, and there is no comprehensive exploration of Greenway environment from a humanistic perspective. Combined with the research and actual situation of the existing representative greenways in Chinese cities, this paper refers to a large number of documents, applies the semantic difference method and multiple regression analysis method, analyzes the current situation of the Dongfengqu greenway, explores the influencing factors and impact evaluation of the greenway environment from the perspective of greenway users' perception, and puts forward suggestions on the optimization of the greenway environment in Zhengzhou from multiple levels. The main conclusion of this paper comes from the data conclusion obtained by semantic difference method, which is feasible in the resident evaluation of greenway use. The feedback results of post use evaluation can provide a reliable reference for the planning and design of similar greenways in the future.

• Journal of Wetlands Research
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• v.24 no.2
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• pp.115-122
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• 2022

As the impermeable area of soil increases due to urbanization, the water circulation system of the city is deteriorating. The existing guidelines for low impact development (LID) facilities installed to solve these water problems or in previous studies, engineering aspects are more prominent than landscaping aspects. This study attempted to present an engineering and landscaping model for reducing pollutants by identifying the effects of vegetation on rainfall outflows and pollutant reduction in bioretention and the economic aspects of planting. Based on the results of artificial rainfall monitoring at Jeonju Seogok Park and the literature on vegetation rainfall runoff and pollutant reduction performance, the best vegetation for reducing pollution compared to cost was Lythrum salicaria L and Salix gracilistyla Miq. was the best vegetation for carbon storage. If you insist to design plants with only these two plantation, there is no choice but to take risks such as biodiversity. Herbaceous plants such as Lythrum salicaria L can be replaced by death of the plants or pests if considered planting various plants. The initial planting cost could expensive, but it is also necessary to mix and plant Salix gracilistyla Miq, which are woody plants that are advantageous in terms of maintenance, according to the surrounding environment and conditions. Based on the conclusions drawn in this study, it can be a reference material when considering the reduction of pollution by species and carbon storage of vegetation in LID facilities.