• Journal of Environmental Impact Assessment
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• v.30 no.2
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• pp.75-88
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• 2021

Six locations in the automated monitoring network at the Geum River Basin were selected forthis study. The water quality characteristics at two of the locations in the water quality monitoring network that were identical, or nearby, were examined, and their correlations were evaluated through statistical analysis. The results of the water quality analysis were converted to the water quality index and expressed in grades for comparison. For the data necessary for the study, public data from four years, from 2016-2019 were used and the evaluation parameters were water temperature, pH, EC, DO, TOC, TN, and TP. Results of the analysis showed that the water quality concentrations measured in the automated monitoring network and the water quality monitoring network differed in some measured values, but they tended to register variation in a specified ratio in most of the locations in the network. The analysis of the correlations of the parameters between the two monitoring networks found that water temperature, EC, and DO showed high correlations between the two monitoring networks. The TOC, TN, and TP showed high correlations, with a 0.7 or higher (correlation coefficient r), with the exception of some of the monitoring networks, although their correlations were lower than those of the basic parameters. The water quality index analysis showed that the water quality index values of the automated monitoring network and the water quality monitoring network were similar. The water quality index decreased and the pollution degree increased in the downstream direction, in both networks.

• Journal of Environmental Impact Assessment
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• v.31 no.2
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• pp.83-94
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• 2022

In this study, DNN-based models were learned using air quality determination data for 2017, 2019, and 2020 provided by the National Measurement Network (Air Korea), and this models evaluated using data from 2016 and 2018. Based on Pearson correlation coefficient 0.2, four items (SO₂, CO, NO₂, PM₁₀) were initially modeled as independent variables. In order to improve the accuracy of prediction, monthly independent modeling was carried out. The error was calculated by RMSE (Root Mean Square Error) method, and the initial model of RMSE was 5.78, which was about 46% betterthan the national moving average modelresult (10.77). In addition, the performance improvement of the independent monthly model was observed in months other than November compared to the initial model. Therefore, this study confirms that DNN modeling was effective in predicting PM_2.5 concentrations based on air pollutants concentrations, and that the learning performance of the model could be improved by selecting additional independent variables.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.2B
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• pp.187-197
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• 2008

This study is to assess the impact of future land use change on hydrology and water quality in Gyungan-cheon watershed ($255.44km^2$) using SWAT (Soil and Water Assessment Tool) model. Using the 5 past Landsat TM (1987, 1991, 1996, 2004) and $ETM^+$ (2001) satellite images, time series of land use map were prepared, and the future land uses (2030, 2060, 2090) were predicted using CA-Markov technique. The 4 years streamflow and water quality data (SS, T-N, T-P) and DEM (Digital Elevation Model), stream network, and soil information (1:25,000) were prepared. The model was calibrated for 2 years (1999 and 2000), and verified for 2 years (2001 and 2002) with averaged Nash and Sutcliffe model efficiency of 0.59 for streamflow and determination coefficient of 0.88, 0.72, 0.68 for Sediment, T-N (Total Nitrogen), T-P (Total Phosphorous) respectively. The 2030, 2060 and 2090 future prediction based on 2004 values showed that the total runoff increased 1.4%, 2.0% and 2.7% for 0.6, 0.8 and 1.1 increase of watershed averaged CN value. For the future Sediment, T-N and T-P based on 2004 values, 51.4%, 5.0% and 11.7% increase in 2030, 70.5%, 8.5% and 16.7% increase in 2060, and 74.9%, 10.9% and 19.9% increase in 2090.

• Korean Journal of Radiology
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• v.22 no.3
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• pp.384-394
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• 2021

Objective: To quantitatively assess biochemical alterations in the cartilage of the subtalar and midtarsal joints in chronic lateral ankle instability (CLAI) patients with isolated anterior talofibular ligament (ATFL) injuries and combined calcaneofibular ligament (CFL) injuries using MRI T2 mapping. Materials and Methods: This study was performed according to regulations of the Committee for Human Research at our institution, and written informed consent was obtained from all participants. Forty CLAI patients (26 with isolated ATFL injuries and 14 with combined ATFL and CFL injuries) and 25 healthy subjects were recruited for this study. All participants underwent MRI scans with T2 mapping. Patients were assessed with the American Orthopedic Foot and Ankle Society (AOFAS) rating system. The subtalar and midtarsal joints were segmented into 14 cartilage subregions. The T2 value of each subregion was measured from T2 mapping images. Data were analyzed with ANOVA, the Student's t test, and Pearson's correlation coefficient. Results: T2 values of most subregions of the subtalar joint and the calcaneal facet of the calcaneocuboid joint in CLAI patients with combined CFL injuries were higher than those in healthy controls (all p < 0.05). However, there were no significant differences in T2 values in subtalar and midtarsal joints between patients with isolated ATFL injuries and healthy controls (all p > 0.05). Moreover, T2 values of the medial talar subregions of the posterior subtalar joint in patients with combined CFL injuries showed negative correlations with the AOFAS scores (r = -0.687, p = 0.007; r = -0.609, p = 0.021, respectively). Conclusion: CLAI with combined CFL injuries can lead to cartilage degeneration in subtalar and calcaneocuboid joints, while an isolated ATFL injury might not have a significant impact on the cartilage in these joints.

• Journal of Radiation Industry
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• v.18 no.3
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• pp.183-193
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• 2024

As part of the social response to the radon bed incident in 2018, the Nuclear Safety and Security Commission took measures to collect and dispose of all radon beds. The Waste Management Act provides landfill disposal as one of the disposal methods for natural radioactive product waste, which is one of the NORM wastes. When NORM wastes are landfilled, workers and the public at the landfill site are exposed to radiation through various pathways, such as leaching of radionuclides through soil and groundwater, and multiple exposure factors are involved simultaneously. In order to improve the reliability of radiological impact assessment, the values of main exposure factors should be selected more accurately. Therefore, before developing the main exposure factors for site characteristics, it is necessary to prioritize main exposure factors reflecting domestic characteristics of NORM waste landfills. Therefore, in this study, the main exposure factors for NORM waste landfill were derived using NDD analysis. To derive the main exposure factors, the analysis tool was first selected as RESRAD-ONSITE computer code, and the exposure scenarios were mainly selected as a resident farmer and suburban resident scenario, recreation scenario, and industrial worker scenario. Then, the priority 1 and 2 factors were selected for sensitivity analysis, and a Korean standard model was established to reflect Korean characteristics. Finally, the sensitivity analysis was conducted through NDD, and the main exposure factors were derived based on this. In the resident farmer scenario, the contaminated zone distribution coefficients of ²²⁶Ra, ²¹⁰Pb, ²³²Th, ²²⁸Ra, ²³⁴U, and ²³⁸U, as well as precipitation and evapotranspiration factors, were derived as the main exposure factors. In the suburban resident scenario, the contaminated zone distribution coefficients of ²²⁶Ra, ²¹⁰Pb, ²³²Th, ²²⁸Ra, ²³⁴U, and ²³⁸U, as well as precipitation and evapotranspiration coefficients, were derived as the main exposure factors. In the recreation scenario, the contaminated zone distribution coefficient of ²³²Th was derived as the main exposure factor. For the industrial worker scenario, the erosion rate was derived as the main exposure factor. The main exposure factors for each scenario were analyzed to be different depending on the scenario characteristics. The results of this study can be utilized as a basis for radiological environmental impact assessment of NORM waste landfill in Korea.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1994.10a
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• pp.49-58
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• 1994

The methods of estimation of VTS effectivenss are compared and the worldwide literature related to the VTS effectiveness is reviewed. The review suggests three potential approaches ; simulation ; synthesis of expert opinion and statistical analysis of casualties. this study adopted dissimilar approaches to estimate the VTS effectiveness to the earlier studies ; the combination of synthesis of expert opinion and causal analysis of casualty. The VTS effectiveness is derived by multiplying casualty rate reduction factors by the effect level of causal factors. The development of casualty rate reduction factors was based on the questionnaire survey and the evolution of effect levels was based on the causal analysis using functional block diagram. According to these procedures the maximum benefit to be obtained through the introduction of a VTS system was approximately 46 percent overall. The collision reduction rate was estimated to be approximately 50 percent for a VTS system with advanced radar surveillance. And 47 percent of groundings 36 percent of rammings and 21 percent of founderings could be reduced by the introduction of VTS. These figures are more or less the same to the earlier studies. The VTS effectiveness by the different causal factor groups was examined. VTS may reduce about 68 percent of causal factors classified as environmental conditions 40 percent of human factors and 35 percent of technical factors in collision accidents. As a whole 60 percent of environmental factors 41 percent of human factors and 20 percent of technical factors may be prevented by a VTS. The key variable of the effectiveness percentage is the value of weight coefficient $\delta$. Therefore differing values for this input was discussed and the impact that these variations have on the VS effectiveness noted. As the results of sensitivity analysis of VTS effectiveness by $\pm$10 percent the effectiveness is varied approximately three to seven percent by casualty type. And the value is changed roughly four to eight percent by a $\pm$10 percent variation by different sub-areas.

• Journal of Digital Convergence
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• v.11 no.2
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• pp.101-114
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• 2013

This paper investigates whether the announcement effect of seasoned equity offering is affected by management performance. We used Korean stock market data from 2000 to 2007 to analyze the possible relation between net income and seasoned equity offerings announcement effect. The sample of 308 firms are selected for the study from the original population of 750 seasoned equity offering announcements. and We analysis this article through event studty of Brown and J.Warner. We divide the data into two groups. - the previous offerings year's positive net income group and negative income group. Both positive and negative net income samples affect stock price positively. However, the CAR for the negative net income offerings becomes zero around 25days after the announcement date. To analyze the impact of accounting income on the seasoned equity offering announcement effects fully, we introduce a cross-sectional regression analysis by setting the cumulative abnormal returns as a dependant variable and net income as an explanatory variable. The beta coefficient of the net income shows a statistical significance. These results can be considered as an evidence to support our hypothesis.

• Journal of Korean society of Dental Hygiene
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• v.10 no.4
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• pp.645-654
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• 2010

Objectives : This study provides dental care organization that is responsible for services of dental hygienists to measure levels of empowerment and organizational commitment to. The impact of empowerment on organizational commitment is a variable that has to validate the improvement of organizational commitment of dental hygienists to have been studied for the suggestions. The study period 2009 July 1 to August 30 at Jeonju Jeollabuk dental material and dental hygienists are working in medical institutions to target a total of 336 copies (88.4%) and for analysis of the data was studied. Methods : For data analysis SPSS (Statistial Package for the Social Science) WIN 12.0 program using frequency analysis, T-test and One-way ANOVA test, Pearson's correlation coefficient, linear regression analysis was conducted through the following. Results : 1. Demographic characteristics (education, salary, age, workplace), the empowerment and organizational commitment as the decisive factor affecting the level was a significant difference. 2. Education, salary, age and demographic characteristics of the working period of the empowerment uimiseong, yeokryangseong, self-determination, but no significant differences in impacts factors, work factors, not only was a significant difference uimiseong. 3. Demographic characteristics (education, salary, age, duration of employment, workplace), the affective commitment, normative commitment, ever, ever commitment and showed significant differences remain. 4. The higher the level of empowerment of the subjects that were higher organizational commitment, was a significant difference. 5. Empowerment and Organizational Commitment of subjects related factors were analyzed in all the variables showed a significant correlation between. Conclusions : Dental health agencies that provide services of dental hygienists to improve empowerment and organizational commitment to develop a structured management program, a dental hygienist job dental hygienist program and professional standards for the continuous and systematic research. That will be needed.

• Journal of The Korean Society of Integrative Medicine
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• v.5 no.4
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• pp.57-66
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• 2017

Purpose : The current study objective was to determine the attitudes of nursing students to death, perception of end-of life care, and perceptions of educational training needs in relation to the provision of end-of life care, and to apply the results to the development of an efficient and effective education program in this regard. Method : Data collection was carried out between March and April 2017, and was achieved through the administration of a questionnaire to 124 caregivers working in a nursing home in C. A self-report instrument was used to measure nursing attitudes to death, perceptions of end-of-life care, and perceptions of educational training needs in relation to the provision of end-of-life care. The collected data were analyzed using SPSS(R) Statistics for Windows(R)(version 21.0), and were calculated was whole numbers, percentages, $mean{\pm}standard$ deviation, and Pearson's correlation coefficient. Results : The average scores obtained were 2.85 out of a maximum of 4.00, 2.14 out of 4.00, and 2.42 out of 4.00, for attitudes to death, perceptions of end-of-life, and perceptions of educational training needs in relation to the provision of end-of-life care, respectively. A positive correlation was found between attitudes to death and perceptions of end-of-life care, and a negative correlation was found between perceptions of end-of-life care and educational training needs in relation to the provision of end-of-life care. Conclusion : The development and implementation of an educational program is necessary to ensure positive attitudes to death in nursing students and improve their perceptions about end-of-life care. Further research is also warranted to determine the impact of such a program in this regard.

• Journal of muscle and joint health
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• v.25 no.1
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• pp.30-38
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• 2018

Purpose: The purposes of this study were to examine the relationships between health literacy, self-efficacy, social support, and medication adherence and to determine its impact on medication adherence in the elderly. Methods: This study was a descriptive research study. Structured questionnaires were used for survey with a convenience sample of 220 elderly in a community. Data were analyzed using descriptive statistics, ANOVA, Pearson's correlation coefficient, and stepwise multiple regression with IBM SPSS 18.0. Results: The mean scores of health literacy, self-efficacy, social support, and medication adherence were $35.89{\pm}19.39$, $55.34{\pm}7.44$, $86.54{\pm}15.90$ and $4.82{\pm}1.83$, respectively. There were significant correlations between health literacy, self-efficacy, social support, and medication adherence. Social support (${\beta}=.23$, p=.001) and health literacy (${\beta}=.21$, p=.002) were significantly associated factors with medication adherence. Conclusion: This finding showed that nursing interventions to promote medication adherence in the elderly group should focus on social support program and health literacy intervention.