• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.565-569
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• 2003

One-year-long groundwater-level data have been collected from 18 wells in Cheon-an area. The result of barometric efficiency, autocorrelation, cross-correlation and statistical distribution evaluated from the measurement data shows that groundwater-level measurements from observation wells are the principal source of information about aquifer characteristics. Data from WA-2 has high barometric efficiency as well as steady decreasing auto-correlation coefficient, which means nonleaky confined aquifer, Most aquifers in this study show the unconfined properties so that barometric efficiencies are mostly low and the coefficients of cross-correlation between groundwater-level and precipitation are commonly high. This study showed that the long-term groundwater-level monitoring data without artificial stress such as pumping would give accurate information about aquifer characteristics.

• Journal of Korean Association for Spatial Structures
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• v.23 no.1
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• pp.35-43
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• 2023

Microclimate analysis was conducted through actual measurement according to land use status in urban, and CFD analysis was conducted to analyze and predict the microclimate characteristics of urban, and compared and analyzed with the actual measurement results. It was measured in high-rise areas and parks, and the temperature of the park area was 0.4 to 0.6℃ lower, and the relative humidity was 1.0 to 3.0% higher. The correlation coefficient was obtained by comparing the results of the computational fluid analysis with the results of the computational fluid analysis at the actual location located within the CFD analysis area for validation. The seasonal correlation coefficients are all higher than 0.8, so it is judged that they can be applied to microclimate analysis in urban area. The computational fluid analysis was divided into three areas (low-rise, low and high-rise, and high-rise) centered on the A2 point. On average, the low-rise area was 0.1 to 0.4% higher than the high-rise area. In the low and high-rise area and high-rise area, the pith of buildings are wide, so the airflow is smooth, so it is judged that the temperature is relatively low.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.4
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• pp.124-129
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• 2017

Clouds are an important factor in aircraft flight. In particular, a significant impact on small aircraft flying at low altitude. Therefore, we have verified and characterized the low level cloud prediction data of the Unified Model(UM) - based Local Data Assimilation and Prediction System(LDAPS) operated by KMA in order to develop cloud forecasting service and contents important for safety of low-altitude aircraft flight. As a result of the low level cloud test for seven airports in Korea, a high correlation coefficient of 0.4 ~ 0.7 was obtained for 0-36 leading time. Also, we found that the prediction performance does not decrease as the lead time increases. Based on the results of this study, it is expected that model-based forecasting data for low-altitude aviation meteorology services can be produced.

• Journal of Environmental Science International
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• v.29 no.8
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• pp.857-870
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• 2020

In this study, the antibiotic components in the final effluent from the 12 wastewater treatment facilities located in the Nakdong River basin were investigated, and the correlation between organic matters, nutrients and antibiotics was analyzed. In the final effluent of the wastewater treatment facilities, three sulfonamides antibiotics (sulfamethazine, sulfathiazole, sulfachlorpyridazine) and tetracyclines antibiotics (oxytetracycline, doxycycline) were detected. Sulfamethazine were detected at all points and ranged from 10.398 to 278.784 ng/L. Sulfathiazole were detected at 6 points (Andong, Gumi, Hapcheon, Miryang, Uiryeong, Haman), and ranged from 23.773 to 144.468 ng/L. The correlation coefficients between sulfathiazole and TSS, COD, TOC, NH₃-N, NO₂-N, and T-N components were high in the range of 0.73 to 0.92. The correlation coefficient between sulfamethazine and T-N was 0.48, and the correlation with the rest of the water quality components was low. The correlation coefficient between sulfamethazine and sulfathiazole was 0.78. Through this study, it was confirmed that the concentration of sulfonamides antibiotics was higher than the concentration of tetracyclines antibiotics in the final effluent of 12 wastewater treatment facilities in the Nakdong River basin, and the concentration of sulfathiazole increased with organic matters and nutrients.

• Journal of Environmental Science International
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• v.29 no.10
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• pp.1003-1010
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• 2020

In this study, the necessity for a village unit Automatic Weather System (AWS) was suggested to obtain correct agricultural weather information by comparing the data of AWS of the weather station with the data of AWS installed in agricultural villages 7 km away. The comparison sites are Hyogyo-ri and Hongseong weather station. The seasonal and monthly averaged and cumulative values of data were calculated and compared. The annual time series and correlation was analyzed to determine the tendency of variation in AWS data. The average values of temperature, relative humidity and wind speed were not much different in comparison with each season. The difference in precipitation was ranged from 13.2 to 91.1 mm. The difference in monthly precipitation ranged from 1.2 to 75.4 mm. The correlation coefficient between temperature, humidity and wind speed was ranged from 0.81 to 0.99 and it of temperature was the highest. The correlation coefficient of precipitation was 0.63 and the lowest among the observed elements. Through this study, precipitation at the weather station and village unit area showed the low correlation and the difference for a quantitative comparison, while the elements excluding precipitation showed the high correlation and the similar annual variation pattern.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.4
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• pp.378-386
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• 2014

The use of bus stop in the center lane has reduced the emissions of exhaust gas on the road due to the improvement of the traffic speed but has caused a health problem for the citizens who are waiting for the bus in the platform, and thus the air pollution control of bus stop in the center lane is emerging as a more important part. This study was conducted to investigate the air pollution degree for the center lane-bus stops in four regions using mobile air measuring vehicle, and to evaluate the characteristics of air pollution by comparing with the data measured at the urban air monitoring site close to the bus stops. In addition, the correlation analysis was performed to analyze the impact to neighboring region by vehicle exhaust gas. The regional mean concentration of nitrogen dioxide in the center lane-bus stops ranged from 0.025 to 0.043 ppm which shows from 2.5 times to 5.3 times higher than the values of urban air monitoring site selected as a control group. The regional mean concentration of ozone in the center lane-bus stops ranged from 0.023 to 0.034 ppm which shows from 3% to 28% lower than the values of urban air monitoring site selected as a control group. The concentrations of nitrogen dioxide and ozone for the sampling regions did not exceed one hour-air quality environmental standard (0.1 ppm). The mean concentration of particulate matter for four center lane-bus stops was $28{\mu}g/m^3$ which shows about 27% higher than the values of urban air monitoring site selected as a control group, and that of particulate matter did not exceed one day-air quality environmental standard ($100{\mu}g/m^3$). In the results of correlation analysis between data from center lane-bus stops and data from urban air monitoring sites, the correlation coefficient (r) of nitrogen dioxide was relatively low as 0.316 to 0.416, and the correlation coefficient was high as the distance was close and vice versa. However, the correlation coefficient of ozone ranged from 0.167 to 0.658 and the correlation coefficient was high as the distance was far and vice versa.

• Korean Chemical Engineering Research
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• v.52 no.4
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• pp.516-521
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• 2014

Axial and overall heat transfer coefficients were investigated in a bubble column with relatively high viscous and low surface tension media. Effects of superficial gas velocity (0.02~0.1 m/s), liquid viscosity ($0.1{\sim}0.3Pa{\cdot}s$) and surface tension ($66.1{\sim}72.9{\times}10^{-3}N/m$) on the local and overall heat transfer coefficients were examined. The heat transfer field was composed of the immersed heater and the bubble column; a vertical heater was installed at the center of the column coaxially. The heat transfer coefficient was determined by measuring the temperature differences continuously between the heater surface and the column which was bubbling in a given operating condition, with the knowledge of heat supply to the heater. The local heat transfer coefficient increased with increasing superficial gas velocity but decreased with increasing axial distance from the gas distributor and liquid surface tension. The overall heat transfer coefficient increased with increasing superficial gas velocity but decreased with increasing liquid viscosity or surface tension. The overall heat transfer coefficient was well correlated in terms of operating variables such as superficial gas velocity, liquid surface tension and liquid viscosity with a correlation coefficient of 0.91, and in terms of dimensionless groups such as Nusselt, Reynolds, Prandtl and Weber numbers with a correlation of 0.92; $$h=2502U^{0.236}_{G}{\mu}^{-0.250}_{L}{\sigma}^{-0.028}_L$$ $$Nu=325Re^{0.180}Pr^{-0.067}We^{0.028}$$.

• The Journal of Korean Medicine
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• v.33 no.1
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• pp.68-78
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• 2012

Objectives: The purpose of this study was to analyze the relationship between Yin-deficiency questionnaire score and various biofunctional signals in women. Methods: A retrospective chart review was performed on charts of 195 patients who visited Gangdong Kyung Hee Hospital between April 1st and September 30th, 2011. The subjects were categorized into two groups, a low Yin-deficiency group (n=118) and a high Yin-deficiency group (n=77). The authors analyzed the correlation between Yin-deficiency questionnaire score and biofunctional signals by Pearson's correlation coefficient test and the difference in biofunctional signals between the two groups by independent samples t-test using SPSS for windows. Results: 1. Negative correlations were observed between the temperature difference of back-humerus, standard deviation of all R-R intervals (SDNN), total power (TP), low frequency (LF), high frequency (HF) on heart rate variability parameters, and Yin-deficiency questionnaire score. A positive correlation was observed between the temperature difference of knee-humerus and Yin-deficiency questionnaire score. 2. The temperature difference of back-humerus in the high Yin-deficiency group was significantly higher than that in the low Yin-deficiency group. The temperature difference of knee-humerus, height, waist-hip ratio, SDNN, TP, LF, and HF of the high Yin-deficiency group were significantly lower than those of the low Yin-deficiency group. Conclusions: The results of this study suggest that the comprehensive diagnosis of Yin-deficiency and biofunctional signals is useful.

• The Journal of Pediatrics of Korean Medicine
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• v.26 no.4
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• pp.38-43
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• 2012

Objectives: The purpose of this study was to investigate the relations between mother's temperament and child's and parenting attitude. Methods: One hundred twenty healthy mothers (above 20 ys) who has a child (7-11 ys) participated after informed consent. The temperament of the children was analyzed by the Junior Temperament and Character Inventory 7-11 (JTCI 7-11) by their mothers. The temperament of the mothers was analyzed by the Temperament and Character Inventory-Revised Short (TCI-RS) and the parenting attitude of the mothers was analyzed by the Parenting Attitude Test (PAT). The relations between mother and child temperament and parenting attitude were assessed using the Pearson correlation coefficient. Results: There were some significant correlations between maternal temperaments and child's temperaments and maternal parenting attitude. Maternal temperament and parenting attitude: Novelty seeking (NS) of mother had low positive correlations with punishment, high expectation and inconsistency. Harm avoidance (HA) had low positive correlations with high involvement and high expectation, and had weak negative correlations with supportive expression and rational explanation. Reward dependence (RD) had low positive correlation with rational explanation. Persistence (P) had low positive correlations with supportive expression, rational explanation and superintendence, and weak negative correlation with high expectation. Child's temperament and parenting attitude: NS of child had low positive correlations with achievement press, high involvement, punishment, high expectation and inconsistency. Low positive correlations were found in many sets such as HA and high expectation, RD and supportive expression and rational explanation, P and supportive expression and rational explanation. Conclusions: These results suggest that there are significant relations between mother and child temperament and parenting attitude the temperament of mother and child.

• Journal of Biomedical Engineering Research
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• v.29 no.6
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• pp.493-501
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• 2008

In this paper, a novel system is proposed to measure skin hydration using the susceptance method. This system largely consists of a low-voltage(${\pm}2.6$ V) driven circuit and minimized electrodes of size($5{\times}5mm^2$). To evaluate the accuracy of the novel system in measuring skin hydration, skin hydration values from 105 subjects are measured by the proposed system. The measurements are then compared to those obtained by the golden reference device based on the capacitance method in terms of Intraclass Correlation Coefficient(ICC) and correlation coefficient. All measurements are performed on 7 sites, which are forehead, Crow's foot, cheek, chin, volar forearm, dorsal forearm, and back of the hand, in a room where the temperature and humidity are maintained at an uniform level of $22{\pm}2^{\circ}C$ and $50{\pm}5%$, respectively. ICC values are above 0.9(p=0.001), signifying that the skin hydration values measured by the two methods show a good level of reliability. Correlation coefficient between the two methods is also 0.562(p=0.001). Based on these results, it is expected that the proposed system may be applicable in a variety of clinical or cosmetic areas.