• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.446-453
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• 2018

The study examines corporate research & development (R&D) expenditure in modern finance. Firms may face one of the essential issues to maintain their optimal levels of R&D expenditures in order to increase corporate profit. Accordingly, financial determinants that may influence R&D spending are statistically tested for firms listed on the KOSPI stock market during the period from 2010 to 2015. Financial determinants which may discriminate between firms in high-growth and low-growth industries are examined on a relative basis. Explanatory variables including one-period lagged R&D expenses (Lag_RD), cross-product term between the Lag_RD and type of industry (as a dummy variable), and advertising expenses (ADVERTISE) significantly influenced corporate R&D intensity. Moreover, high-growth firms in domestic capital markets showed higher Lag_RD, profitability (PROF) and foreign equity ownership (FOS) than their counterparts in low-growth sectors, whereas low-growth firms had higher market-value based leverage (MLEVER) and ADVERTISE. Overall, these results are expected to influence decision-making of firms concerning the optimal level of R&D expenditure, which may in turn enhance shareholder wealth.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.301-310
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• 2018

This study was conducted to investigate the relationship between physical function (ADL, IADL) and mental function (depression, cognitive dysfunction) and quality of life in the elderly. The subjects of this study were 524 elderly people aged 65 or older who were admitted to 15 care facilities located in D metropolitan city. Data were collected through a personal interview conducted by interviewers that visited each care facility from November 2015 to January 2016. T-tests and ANOVA were used to compare the quality of life score for each independent variable, while multiple regression was used to determine the explanatory power of independent variables that affected quality of life. Quality of life was significantly lower among those of older age, lower educational level, living alone, with lower relationships with children, lower subjective health status, disability, lower ability for mastication, without regular eating habits, without regular exercise, and without regular health checkups. In addition, quality of life was significantly lower in the ADL and IADL, as well as among those with a higher depression level and lower cognitive impairment scores than their respective counterparts. The results of this study suggest that the quality of life among elderly that have been admitted to care facilities is significantly related to physical and mental functions as well as demographic characteristics, health status and health related behavioral characteristics.

• The Korean Journal of Applied Statistics
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• v.19 no.1
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• pp.1-12
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• 2006

The aim of this study is to analyse a survey data on the number of charitable donations using a mixture of two Poisson regression models. The survey was conducted in 2002 by Volunteer 21, an nonprofit organization, based on Koreans, who were older than 20. The mixture of two Poisson distributions is used to model the number of donations based on the empirical distribution of the data. The mixture of two Poisson distributions implies the whole population is subdivided into two groups, one with lesser number of donations and the other with larger number of donations. We fit the mixture of Poisson regression models on the number of donations to identify significant covariates. The expectation-maximization algorithm is employed to estimate the parameters. We computed 95% bootstrap confidence interval based on bias-corrected and accelerated method and used then for selecting significant explanatory variables. As a result, the income variable with four categories and the volunteering variable (1: experience of volunteering, 0: otherwise) turned out to be significant with the positive regression coefficients both in the lesser and the larger donation groups. However, the regression coefficients in the lesser donation group were larger than those in larger donation group.

• Journal of Cadastre & Land InformatiX
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• v.48 no.1
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• pp.169-186
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• 2018

The social influence of the elderly population will accelerate in a rapidly aging society. The purpose of this study is to establish a methodology for extracting vulnerable districts of the welfare of the aged through machine learning(ML), artificial neural network(ANN) and geospatial analysis. In order to establish the direction of analysis, this progressed after an interview with volunteers who over 65-year old people, public officer and the manager of the aged welfare facility. The indicators are the geographic distance capacity, elderly welfare enjoyment, officially assessed land price and mobile communication based on old people activities where 500 m vector areal unit within 15 minutes in Yongin-city, Gyeonggi-do. As a result, the prediction accuracy of 83.2% in the support vector machine(SVM) of ML using the RBF kernel algorithm was obtained in simulation. Furthermore, the correlation result(0.63) was derived from ANN using backpropagation algorithm. A geographically weighted regression(GWR) was also performed to analyze spatial autocorrelation within variables. As a result of this analysis, the coefficient of determination was 70.1%, which showed good explanatory power. Moran's I and Getis-Ord Gi coefficients are analyzed to investigate spatially outlier as well as distribution patterns. This study can be used to solve the welfare imbalance of the aged considering the local conditions of the government recently.

• Journal of Korea Port Economic Association
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• v.26 no.3
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• pp.1-17
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• 2010

This paper focuses on measuring the efficiency of container yards in container terminals in Busan and Gwangyang using Data Envelopment Analysis (DEA) approach. It analyses the relative efficiency of 11 container terminals based on the data for the period between 2006 and 2009 to offer a fresh perspective. The applied framework assumes inputs to be container cranes, transtainer cranes and yard tractors and output as container transshipment volume. Through the analysis, the differences between the impact of using of container cranes, transtainer cranes and yard tractors, top handler & reach stacker on container yard efficiency are measured. Moreover, the associations between the three input factors are analyzed as well. This paper also employs heteroscedastic Tobit model to show the impact of explanatory variables on container yard efficiencies. I took into consideration the strategies for operation of container cranes, transtainer cranes and yard tractors in container yard.

• Journal of Digital Convergence
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• v.15 no.10
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• pp.281-291
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• 2017

This purpose of study was to identify variables predicting basic psychological need in hemodialysis patients. The participants were 134 patients from two major general hospitals and two dialysis center located in J city. Data were collected using self-report questionnaires and physiological index. Data analysis was done by using SPSS WIN 18.0 program for one-way ANOVA, independent t-test, Pearson correlation coefficients, and multiple regression. This study showed a negative correlation between basic psychological need and uncertainty(r=--.464, p<.001), depression(r=-.422, p<.001). In addition, relationships and physiological index were Positively correlated. The uncertainty(${\beta}=-.345$), depression(${\beta}=-.279$), physiological index(${\beta}=-.117$) have a 29% explanatory power for the basic psychological need in hemodialysis patients. Physiological index, uncertainty and depression in turn influenced the basic psychological needs of hemodialysis patients. It is necessary to develop nursing strategies and programs to reduce disease uncertainty and depression in order to increase self-deterministic health behavior through autonomy, competence and relationship satisfaction.

• Journal of Digital Convergence
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• v.15 no.10
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• pp.367-376
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• 2017

The purpose of this study was to identify the impact of empowerment on achievement in the team based learning by college nursing students and the mediation effects of co-regulation. A convenience sample of 243 subjects were recruited from one university in G city. And data were collected from May 23 to May 30, 2017. Data were analyzed using descriptive statistics, t-test, ANOVA, Pearson's Correlation, Multiple regression analyses with SPSS 21.0 Program. The psychological empowerment showed a significantly positive correlation of co-regulation and achievement, co-regulation showed a significantly positive correlation of achievement. The factors affecting the achievement were co-regulation, psychological empowerment, improvement on cooperation and modification, grade, and explanatory power was 57.2%. Co-regulation had a partial mediating effect in the relationship between shared psychological empowerment and Achievement. This study provided basic data for developing the nursing education program to improve achievement. and it is necessary to repeat the study including various variables related to achievement of the task in the future.

• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.266-278
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• 2012

The objective of this study was developing dynamic stand growth model to predict diameter at breast height (DBH) growth by thinning intensity and cycle for major tree species of South Korea. The yield table, one of static stand growth models, constructed by Korea Forest Service was employed to prepare dynamic stand growth models for 8 tree species. In the process of model development, the thinning type was designated to thinning from below and equations for predicting the DBH change after thinning by different intensities was generated. In addition, stand density (N/ha), age and site index were adopted as explanatory variables for DBH prediction model. Thereafter, using the model, DBH growth under various silvicuture through integrating such equations considering thinning intensities, and cycles. The dynamic stand growth model of DBH developed in this study can provide understanding of effectiveness in forest growth and growing stock when thinning practice is performed in forest. Furthermore, results of this study is also applicable to quantitatively assess the carbon storage sequestration capability.

• KDI Journal of Economic Policy
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• v.14 no.4
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• pp.51-62
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• 1992

The purpose of this paper is to estimate the ratio of under-reported business income and related tax to that which is actually reported. The business income and tax are vulnerable to being under-reported. Information about the business income and thus income tax is private information. Without information costs, the tax agency cannot collect all the information about the business income and income tax. In Korea there are more than 600,000 proprietors. Therefore, the costs to investigate the accuracy of the taxpayes' reports are substantial. The tax agency sets a level over which proprietors should report income ratio to total sales, which induces the under-report. To estimate the ratio of under-reported tax, the expenditure method is employed. By this method, the under-reported income can be easily presumed based on expenditures since expenditures are closely related to income. First, the consumption function is estimated by using cross-section data of 1986-89. Generally, the estimation results show the expected sign of the coefficients of the explanatory variables such as income, wealth, and family size. Second, the extent of under-reported business income and related tax is estimated by using the estimation results. The estimated ratios of under-reported tax and income to the actual tax and income fall in the range of 13~39% and 8~25% respectively. This estimation confirms the increasing tendency of the tax detection ratio in previous studies. However, it should be noted that this study is not based on data of the tax report but those of the urban household survey. Therefore, there still remains the possibility that the ratio of under-reported tax could be underestimated.

• Journal of the Korea Convergence Society
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• v.9 no.6
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• pp.299-310
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• 2018

A Convergence study was conducted to investigate the factors influencing the health-related quality of life in patients with chronic neck pain and to present a strategy for effective program development. The participants of this study were 92 patients with chronic neck pain in a region and collected data by self-reported questionnaire. Data were analyzed using PASW 18.0 program, that descriptive statistics, t-test, ANOVA, correlation analysis and stepwise multiple regression analysis were performed. According to the results of stepwise multiple regression, the identified influencing factors were disability(${\beta}=-.403$, p<.001), depression(${\beta}=-.313$, p<.001), age(${\beta}=-.194$, p=.008), muscle disorder(${\beta}=-.176$, p=.009), education(${\beta}=-.151$, p=.043) with health-related quality of life in patients with chronic neck pain. The explanatory power($R^2$) by 5 variables was 67.1%(F=38.118, p<.001). It was found that it is important to consider the individual characteristics, physical function improvement and psychological support for improving the health-related quality of life in patients with chronic neck pain. Therefore, it is necessary to develop a health promotion program based on the factors influencing on the health-related quality of life and analyze its application effect.