• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1164-1168
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• 2010

수자원이 우리 생활의 전반적으로 중요한 역할을 차지하면서 댐의 효율적인 운영과 안정적인 용수공급에 대한 연구는 지속적으로 수행되어지고 있다. 1990년대 이후 비선형적인 특성을 잘 모의하는 장점을 가진 인공신경망(ANN)을 이용하여 유입량 예측에 대한 많은 연구가 수행되었다. 하지만 ANN 모형을 포함한 회귀모형은 월 강우 및 유입량의 예측에 대해 간편하게 사용을 할 수 있지만, 예측의 정확성에 한계를 가지고 있다. 본 연구에서는 ANN 모형과 회귀모형의 예측오차를 후처리 과정을 통하여 오차를 줄임으로써 예측모형의 성과를 향상시키는 방법을 제안하였다. 연구지역은 금강수계의 대청댐 유역으로, 1982년 9월부터 2005년 12월에 해당하는 유역 내 11개 지점의 강우관측소에서 관측한 월 강우와 댐 유입량을 수집하여 모형을 구축하였다. 강우량과 유입량 자료에 대해 자기상관함수와 교차상관함수를 이용하여 입력변수를 결정하였고, 정규화를 통한 전처리 과정을 거쳐 ANN 모형과 회귀모형을 이용한 예측모형을 구축하였으며, 예측성과의 향상을 위하여 군집 분석을 이용하여 오차를 재조정하였다. 이러한 오차 후처리 과정을 포함한 모형은 RMSE와 상관계수를 이용하여 비교 평가한 결과, 예측성과를 약 40% 정도 향상시켰다.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.1
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• pp.1-18
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• 2019

This research measured and visualized the spatial dependency and the spatial heterogeneity of the small business in Cheonan-si, Asan-si with $100m{\times}100m$ grids based on global and local spatial autocorrelation. First, we confirmed positive spatial autocorrelation of small business in the research area using Moran's I Index, which is ESDA(Exploratory Spatial Data Analysis). And then, through Getis-Ord $GI{\ast}$, one kind of LISA(Local Indicators of Spatial Association), local patterns of spatial autocorrelation were visualized. These verified that Spatial Regression Model is valid for the location factor analysis on small business commercial buildings. Next, GWR(Geographically Weighted Regression) was used to analyze the spatial relations between the distribution of small business, hourly mobile traffic-based floating population, land use attributes index, residence, commercial building, road networks, and the node of traffic networks. Final six variables were applied and the accessibility to bus stops, afternoon time floating population, and evening time floating population were excluded due to multicollinearity. By this, we demonstrated that GWR is statistically improved compared to OLS. We visualized the spatial influence of the individual variables using the regression coefficients and local coefficients of determinant of the six variables. This research applied the measured population information in a practical way. Reflecting the dynamic information of the urban people using the commercial area. It is different from other studies that performed commercial analysis. Finally, this research has a differentiated advantage over the existing commercial area analysis in that it employed hourly changing commercial service population data and it applied spatial statistical models to micro spatial units. This research proposed new framework for the commercial analysis area analysis.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.366-374
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• 2017

This study was conducted to explore the degree of female nursing student's dietary behavior, self esteem, dietary self-efficacy, life stress and the factors influencing dietary behavior of those surveyed. A total of 422 female nursing students in B, C city were surveyed. The data were collected between May 15 and 30 of 2016 and analyzed by a t-test, ANOVA, Pearson's correlation coefficients, and multiple regression analysis using SPSS WIN/21.0. The mean score of dietary behavior was $3.01{\pm}0.49$. In addition, there were significant differences in dietary behavior with respect to grade(F=4.823, p=0.008), residential type(F=6.067, p<.001), academic grade(F=3.907, p=0.021), health status(F=7.975, p<0.001), and degree of health concern(F=4.189, p=0.016). Moreover, there were negative correlations between dietary behavior and self esteem(r=-.238, p<0.001), and dietary self-efficacy(r=-0.438, p<0.001), while there was a positive correlation between dietary behavior and life stress(r=0.194, p<0.001). Regression analysis showed 26.7% of variance in female nursing student's dietary behavior can be explained by dietary self-efficacy, life stress, residental type, and degree of health concern. A follow-up survey investigating various factors influencing female nursing student's dietary behavior is needed and increased dietary behavior education and programs are required.

• The Journal of the Convergence on Culture Technology
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• v.8 no.3
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• pp.521-528
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• 2022

The purpose of this study was to investigate the effect of perceived stress, self-efficacy, interpersonal relationship of college life adaptation in college students. Data were collected from 2,956 college students in B city and analyzed by t-test, ANOVA, Pearson correlation coefficient, and multiple regression using SPSS/WIN 22.0. The degree of suicide ideation in nursing students was 3.33±5.28. There were significant differences in college life adaptation with department(F=9.932, p<.001), number of friend(F=5.681, p<.001), close professor (t=-3.739, p<.001), There was negative correlation between college life adaptation and perceived stress(r=-.543, p<.001), positive correlation between college life adaptation and self-efficacy(r=.667, p<.001), interpersonal relationship(r=.679, p<.001). The factors affecting college life adaptation of the study subjects were perceived stress(β=-.191, p<.001), self-efficacy(β=.280, p<.001), interpersonal relationship(β=.394, p<.001), with an explanatory power of 56.7%. Through the result of this study, it is necessary to development education and program that to improve college life adaptation in college students.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.25 no.3
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• pp.165-171
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• 2013

The fact that tidal residuals are detected greatly at the tide-dominated region implies that tide component has still remained in the tidal residual. Auto-correlation function analysis also show that the auto-correlation coefficients are conspicuous near tidal periods at the Western Coast. A wavelet method was used to analyze characteristics of the short period or tide-relevant residuals. Considering the results that tidal period is prominent at the tide-dominated region, that seasonal variation is trivial at the short periods, and that shallow tidal period is conspicuous at Mokpo, the short period can be considered to be correlated with tide modulated surge. The result also shows short period components stem mainly from tide-forecasting error and tide-surge interaction. Thus tide modulated surge must be distinguished from meteorological surge.

• Journal of the Korean Geographical Society
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• v.45 no.6
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• pp.806-819
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• 2010

Population data has been essential and fundamental in spatial analysis and commonly aggregated into political boundaries. A conventional method for population distribution estimation was a regression model with land use data, but the estimation process has limitation because of spatial autocorrelation of the population data. This study aimed to improve the accuracy of population distribution estimation by adopting a Regression-Kriging method, namely RK Model, which combines a regression model with Kriging for the residuals. RK Model was applied to a part of Seoul metropolitan area to estimate population distribution based on the residential zones. Comparative results of regression model and RK model using RMSE, MAE, and G statistics revealed that RK model could substantially improve the accuracy of population distribution. It is expected that RK model could be adopted actively for further population distribution estimation.

• Korean Journal of Psychosomatic Medicine
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• v.29 no.1
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• pp.49-57
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• 2021

Objectives : This study evaluated the medical communication skills of trainee doctors and analyzed the relationship between medical communication skills, self-efficacy on clinical performance (SECP) and empathy. Methods : A total of 106 trainee doctors from a university hospital participated. The questionnaire comprised self-evaluated medical communication skills, modified SECP and the Korean version of the Jefferson Scale of Empathy-Health Professionals version. The mean difference in medical communication skills scores according to gender, age, division (intern, internal medicine group or surgery group) and position (intern, first-/second- and third-/fourth-year residents) were analyzed. Pearson correlation coefficients were determined between medical communication skills, modified SECP and empathy. The effects of each variable on medical communication skills were verified using the structural equation model. Results : There were no statistically significant mean differences in self-evaluated medical communication skills according to gender, age, division or position. Medical communication skills had a significant positive correlation with modified SECP (r=0.782, p<0.001) and empathy (r=0.210, p=0.038). Empathy had a direct effect on modified SECP (β=0.30, p<0.01) and modified SECP had a direct effect on medical communication skills (β=0.80, p<0.001). Empathy indirectly influenced medical communication skills, mediating modified SECP (β=0.26, p<0.05). Conclusions : Medical communication skills are an important core curriculum of residency programs, as they have a direct correlation with SECP, which is needed for successful treatment. Moreover, the medical communication needs a new understanding that is out of empathy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.589-598
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• 2016

The aim of this study was to investigate the relationship among the variables and the influence of academic self-efficacy and critical thinking disposition on the problem solving ability of nursing students. A descriptive research design was employed in this study. The participants were 404 sophomore nursing students in D city, who were surveyed between May 2 and May 20, 2016, using self-report questionnaire. The data were analyzed with SPSS WIN 21.0 using descriptive statistics, ANOVA, t-test, Scheffe test, Pearson's correlation coefficient, and multiple stepwise regression analysis. Significant correlations among the academic self-efficacy, critical thinking disposition, and problem solving ability were found. In academic self-efficacy and critical thinking disposition, there were significant differences in gender, academic credit, interpersonal relationship, and satisfaction with nursing as a major. The problem solving ability showed statistically significant differences in academic credit, interpersonal relationships, and satisfaction with nursing as a major. The regression model explained 51.7% of the effect on the problem solving ability. Academic self-efficacy and critical thinking disposition were factors influencing the problem solving ability of nursing students. Based on these results, to increase problem solving ability of nursing students, it will be necessary to develop an educational program and strategy for improving the academic self-efficacy and critical thinking disposition.

• Journal of Digital Convergence
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• v.17 no.2
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• pp.207-216
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• 2019

The purpose of this study was to examine to identify factors affecting wellness of workers. This study collected questionnaire data from 172 workers from two large workplaces more than 1,000 workers are located in G city. Data were analyzed using descriptive statistics, Pearson correlation coefficient and Hierarchical regression with IBM SPSS statistics 20.0 program. Wellness of worker was correlated with exercise self-efficacy(r=.23, p<.05), autonomous motivation(r=.38, p<.001), exercise behavior(r=.61, p<.001). Hierarchical regression analysis showed that exercise self-efficacy(${\beta}=.34$, p<.001), exercise behavior(${\beta}=.30$, p<.001), subjective health status(${\beta}=-.23$, p<.001), subjective economic status(${\beta}=-.13$, p=.016) explained 57.3%(F=39.29, p<.001) of wellness of workers. Based on the finding, there is a need to develop an intervention program that consider exercise self-efficacy, exercise behavior, subjective health status and subjective economic status.

• Korean Journal of Child Education & Care
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• v.17 no.4
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• pp.145-161
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• 2017

The purpose of this study was to analyze the relationship among NCS basic vocational competencies, Teaching Personality Aptitude and DISC behavior type of pre-preschool teachers. The subjects were 110 pre-preschool teachers attended in D university located in Kyonggido. 'NCS basic vocational competencies scale', 'Teaching Personality and Aptitude scale', and 'DISC behavior type scale' were used in the collection of data. It used Pearson's correlation Analysis to analyze the data. The results of this study are as follows; first, there was positive correlations between dominance trait and mathematical competency. And, there was positive correlations between interaction trait and self-development competency. And there were negative correlations between support traits and NCS basic vocational competencies. Second, it was revealed that positive correlations between almost sub scale's of NCS basic vocational competencies and teacher teaching personality aptitude. Third, there was positive correlations between dominance trait and sub scale of teaching personality aptitude(e.g.: problem solving/ inquiry skills, judgment, creativity/practical ability, leadership, knowledge/information ability, planning ability, sincerity/responsibility). And there were negative correlations between support traits and sub scale of teaching personality aptitude(e.g.: problem solving/ inquiry skills, judgment, creativity/practical ability, leadership, sincerity/responsibility).