• Journal of Soil and Groundwater Environment
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• v.10 no.1
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• pp.65-74
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• 2005

National groundwater monitoring stations have been managed throughout the country by Korea Water Resources Corporation (KOWACO) in order to monitor variations in quantity and quality of groundwater resources. A multi-sensor installed in each monitoring station well measures groundwater level, water temperature and electrical conductivity every six hours and the logged data are automatically transmitted to a host computer in KOWACO. Meanwhile despite regular station inspection and replacement of deteriorate or broken devices, abnormal values or outliers often occur due to intrinsic limitations of automatic monitoring and transmission. Thus prompt recognition and measures to these values are essentially required to reduce disturbance and missing period of the data. In this study, time and frequency of outlier occurrence were analyzed for the water level data obtained from national groundwater monitoring stations within the Han river basin in 2000. The analysis results indicated that the most prominent patterns of the outliers were rapid decline for water level, no variation for temperature and steep decline for electrical conductivity. This study provided a sample criterion for determining the outlier for each parameter.

• Korean Journal of Remote Sensing
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• v.38 no.5_3
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• pp.953-966
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• 2022

Since aerosols adversely affect human health, such as deteriorating air quality, quantitative observation of the distribution and characteristics of aerosols is essential. Recently, satellite-based Aerosol Optical Depth (AOD) data is used in various studies as periodic and quantitative information acquisition means on the global scale, but optical sensor-based satellite AOD images are missing in some areas with cloud conditions. In this study, we produced gap-free GeoKompsat 2A (GK-2A) Advanced Meteorological Imager (AMI) AOD hourly images after generating a Random Forest based gap-filling model using grid meteorological and geographic elements as input variables. The accuracy of the model is Mean Bias Error (MBE) of -0.002 and Root Mean Square Error (RMSE) of 0.145, which is higher than the target accuracy of the original data and considering that the target object is an atmospheric variable with Correlation Coefficient (CC) of 0.714, it is a model with sufficient explanatory power. The high temporal resolution of geostationary satellites is suitable for diurnal variation observation and is an important model for other research such as input for atmospheric correction, estimation of ground PM, analysis of small fires or pollutants.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.3
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• pp.153-159
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• 2013

Purpose: Nowadays, checkbite methods and a digital sensor are used to analyze the movement of mandible. However, there are no study comparing two methods. Therefore, this study has compared measuring the condylar inclination methods by using the new ARCUSdigma 2 system and the checkbite method. Materials and methods: Young 20 adults without any orthodontic treatment experiences, missing teeth, and restorations with the change of occlusal plane were tested. Angles of condylar path were measured 3 times each, based on Camper's line, by using two methods. KaVo PROTAR Evo 7 semi-adjustable articulator was used and the data were statistically analyzed. Results: 1. The anterior sagittal condylar inclination by ARCUSdigma 2 system were measured as $26.97^{\circ}({\pm}7.38^{\circ})$ on the left side and $29.80^{\circ}({\pm}8.19^{\circ})$ on the right side. The lateral condylar inclination were measured as $5.75^{\circ}({\pm}3.47^{\circ})$ on the left side and $8.10^{\circ}({\pm}4.98^{\circ})$ on the right side. 2. The anterior sagittal condylar inclination by checkbite method were measured as $25.20^{\circ}({\pm}6.53^{\circ})$ on the left side and $28.18^{\circ}({\pm}7.38^{\circ})$ on the right side. The lateral condylar inclination were measured as $10.97^{\circ}({\pm}5.63^{\circ})$ on the left side and $12.03^{\circ}({\pm}5.22^{\circ})$ on the right side. There was no statistically significant difference between male and female (P>.05). 3. The lateral condylar inclinations of ARCUSdigma 2 were statistically significantly smaller than that of checkbite method (P<.05). Conclusion: In Both of 2 methods, there was no statistically significant difference between male and female (P>.05). However, the lateral condylar inclinations of ARCUSdigma 2 were statistically significantly smaller than that of checkbite method (P<.05).