• Journal of the Korea Society for Simulation
• /
• v.23 no.4
• /
• pp.189-195
• /
• 2014

In this paper, we conducted a study on place-free and time-free cloud computing (CC) adoption decision-making model. Panel survey data which is collected from 65 people and CART (classification and regression tree) which is one of data mining approaches are used to construct decision-making model. In this modeling, there are 2 steps: In the first step, significant questions (variables) are selected. After that, the CART decision-making model is constructed using the selected variables. In the variable selection stage, the 25 questions are reduced to 5 ones. The benefits of question reduction are quick response from respondent and reducing model-construction time.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2016.05a
• /
• pp.166-167
• /
• 2016

Unlike the past, supported by the development of digital technologies, free-form buildings are frequently designed with creative thoughts of architectural designers. However, there are some difficulties preventing successfully completion of projects, like reduced productivity and increased construction duration and cost upon the process of producing and installing concrete panels for free-form structures. In particular, there are active studies on the CNC machine for production of free-form concrete panels. Yet, it is difficult to effectively and easily come up with information on production and installation of free-form, curve-surfaced panels which are difficult to be mathematically defined. This requires a lot of manpower and time to implement the curved surfaces of free-form buildings as intended by architects. Accordingly, it needs a model that can effectively create production-installation data of free-form concrete panels for successful free-form building projects. Thus, the purpose of the study is to suggest data estimation model of production-installation using mathematical algorithm in free-form concrete panels. The study results will realize effective production and installation of free-form concrete members, allowing improved productivity of projects, reduced cost and shortened construction duration.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.37 no.3
• /
• pp.122-128
• /
• 2014

When evaluating effectiveness of a program, there is a tendency to simply compare the performances of the treated before and after the program or to compare the differences in the performances of the treated and the untreated before-after the program. However, these ways of evaluating effectiveness have problems because they can't account for environmental changes affecting the treated and/or effects coming from the differences between the treated and the untreated. Therefore, in this paper, panel data analysis (fixed effects model) is suggested as a means to overcome these problems and is utilized to evaluate the effectiveness of fusion technology program conducted by Ministry of Trade, Industry and Energy, Korea. As a result, it turns out that the program has definitely positive impacts on the beneficiary in terms of sales, R&D expenditure, and employment.

• Journal of Environmental Science International
• /
• v.22 no.9
• /
• pp.1171-1180
• /
• 2013

Recent climate change has led to fluctuations in agricultural production, and as a result national food supply has become an important strategic factor in economic policy. As such, in this study, panel data was collected to analyze the effects of seven meteorological elements and using the Lagrange multipliers method, the fixed-effects model for the production of five types of food crop and the seven meteorological elements were analyzed. Results showed that the key factors effecting increases in production of rice grains were average temperature, average relative humidity and average ground surface temperature, while wheat and barley were found to have positive correlations with average temperature and average humidity. The implications of this study are as follow. First, it was confirmed that the meteorological elements have profound effects on the production of food crops. Second, when compared to existing studies, the study was not limited to one food crop but encompassed all five types, and went beyond other studies that were limited to temperature and rainfall to include various meterological elements.

• Journal of Preventive Medicine and Public Health
• /
• v.48 no.6
• /
• pp.319-329
• /
• 2015

Objectives: Parental socioeconomic status (SES) exerts a substantial influence on children's health. The purpose of this study was to examine factors determining children's private health insurance (PHI) enrolment and children's healthcare utilization according to PHI coverage. Methods: Korea Health Panel data from 2011 (n=3085) was used to explore the factors determining PHI enrolment in children younger than 15 years of age. A logit model contained health status and SES variables for both children and parents. A fixed effects model identified factors influencing healthcare utilization in children aged 10 years or younger, using 2008 to 2011 panel data (n=9084). Results: The factors determining children's PHI enrolment included children's age and sex and parents' educational status, employment status, and household income quintile. PHI exerted a significant effect on outpatient cost, inpatient cost, and number of admissions. Number of outpatient visits and total length of stay were not affected by PHI status. The interaction between PHI and age group increased outpatient cost significantly. Conclusions: Children's PHI enrolment was influenced by parents' SES, while healthcare utilization was affected by health and disability status. Therefore, the results of this study suggest disparities in healthcare utilization according to PHI enrollment.

• Journal of Family Resource Management and Policy Review
• /
• v.18 no.2
• /
• pp.163-182
• /
• 2014

This study examined the effects of informal grandparent-provided child care and support on married women's additional birth plans. This study applied panel data analysis to three waves of the Korean Longitudinal Survey of Women and Family (KLoWF) and obtained two major findings, as follows. First, having a mother-in-law and co-residing with parents-in-law had a positive influence on married working women's additional birth plans. Child care provision from the parents of a married working woman also positively influenced her additional birth plans. Second, the analysis showed that housework assistance from a woman's mother-in-law or mother had no effect on her birth plans in both models investigated: the additional birth plan model for all women, both employed and unemployed, and the additional birth plan model for only working women. In conclusion, the findings of this study demonstrated that child care availability, with grandparents as the trusted providers, is a more important factor in married women's additional birth plans than housework assistance from their mothers-in-law and mothers.

• Survey Research
• /
• v.11 no.1
• /
• pp.43-61
• /
• 2010

This research estimated the variation of high school students' academic achievement by using the second to the fourth wave KEEP(Korea Education and Employment Panel) data. We explored the effects of study on academic achievement in proportion to self-regulated learning hours(except for school work and private tutoring). Analysis variables were self-directed learning(study) hours throughout senior high school and 9 grade academic achievement. We conducted Latent Growth Model(LGM) using KEEP panel data and program LISREL 8.8. Results showed that there were significant effects of self-regulated learning hours on the variation of senior high school students' academic achievement. Therefore, this was considered to be useful tips in getting the relation between students' learning and academic achievement.

• Current Photovoltaic Research
• /
• v.10 no.1
• /
• pp.6-15
• /
• 2022

Climate change is among the most important issues facing mankind in modern society. However, global PV energy expansion has been driven mainly by OECD countries. We investigate the determinants of PV energy growth by panel data of selected OECD countries from 1991 to 2018. We investigate four categories of driving factors: socioeconomic, technological, country specific, and policy factors. The test results support that PV capacity growth is significantly driven by technology development and multidimensional environment policy factors. Socioeconomic factors such as CO₂, GDP, and electricity price are statistically significant on the growth of PV energy, too. Whereas, country-specific solar potential factor is the least related. As most of the socioeconomic factors are exogenous, we need to focus more on PV technology development and policy measures.

• Communications for Statistical Applications and Methods
• /
• v.21 no.1
• /
• pp.45-60
• /
• 2014

We introduce a MCMC sampling for a generalized linear normal random effects model with the ordered probit link function based on latent variables from suitable truncated normal distribution. Such models have proven useful in practice and we have observed numerically reasonable results in the estimation of fixed effects when the random effect term is provided. Applications that utilize Korean Welfare Panel Study data can be difficult to model; subsequently, we find that an ordered probit model with the random effects leads to an improved analyses with more accurate and precise inferences.

• The Journal of Asian Finance, Economics and Business
• /
• v.7 no.12
• /
• pp.85-93
• /
• 2020

This study aimed to explore the impact of macroeconomic (Real GDP growth (GDPG), Inflation rate (INF)) and bank -specific variables (profitability (ROA), capital adequacy (CADEQ), non-performing loans (NPL), deposit growth (DEPG)) on the liquidity (lIQ) of 13 listed Jordanian commercial banks for the period 2011-2018. Panel data analysis, Pooled least square, fixed effects model and random effects model, Lagrange multiplier test, and Hausman test were used. The random effects model output shows that, macroeconomic variables have a significant impact on Jordanian commercial banks liquidity since inflation has a positive impact while GDPG has a negative impact on banks (LIQ). On the other hand among the bank-specific variables capital adequacy and deposit growth have a positive significant impact on banks (LIQ), while (NPL) and (SIZE) have a negative significant impact on Jordanian commercial banks liquidity. But ROA has a negative insignificant impact on (LIQ). The findings of the study suggest that commercial banks departments need to pay attention to the economic and internal variables of banks in order to maintain acceptable levels of liquidity.