• Journal of the Korean Operations Research and Management Science Society
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• v.29 no.2
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• pp.19-43
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• 2004

This study was motivated by a practical need for estimating the macroeconomic effect of government IT Promotion investment, specifically for micro and small firms. Small firms have been in a disadvantageous position to adopt and utilize new IT compared with medium or large-sized firms. Small firms don't have enough resource to acquire IT in general, therefore private IT companies don't have much incentive to develop IT services and products for small firms. Lack of feasible IT solutions for small firms again restricted active IT adoption of small firms. Government recognized the vicious cycle, therefore decided to promote private IT companies to develop IT services and products for small firms's. Our main concern was to identify a relevant government supporting Policy, especially in the amount and the period. To do this, we first constructed a system dynamics simulation model to Investigate important factors and causal relationships among them. Simulation results showed 2.19% of GDP contribution and 0.16% of employment contribution in max from small firms' IT adoption. Also we could find that investing proper amount for a short period would be for better than maintaining Investing small amount for a long period.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.2
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• pp.187-196
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• 2006

Forecasting the long-term water demand is important in the plan of water supply system because the location and capacity of water facilities are decided according to it. To forecast the long-term water demand, the existing method based on lpcd and population has been usually used. But, these days the trend among the variation of water demand has been disappeared, so expressing other variation of it is needed to forecast correct water demand. To accomplish it, we introduced the System Dynamics method to consider total connections of water demand factor. Firstly, the factors connected with water demand were divided into three sectors(water demand, industry, and population sectors), and the connections of factors were set with multiple regression model. And it was compared to existing method. The results are as followings. The correlation efficients are 0.330 in existing model and 0.960 in SD model and MAE are 3.96% in existing model and 1.68% in SD model. So, it is proved that SD model is superior to the existing model. To forecast the long-term water demand, scenarios were made with variations of employment condition, economic condition and consumer price indexes and forecasted water demands in 2012. After all scenarios were performed, the results showed that it was not needed to increase the water supply ability in Seoul.

• Economic Analysis
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• v.26 no.4
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• pp.39-64
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• 2020

Typical business cycle models have difficulties in explaining key macroeconomic labor market variables, such as employment and unemployment, as they usually consider labor hour choices only. In this paper, we introduce labor market search and matching frictions into a New Keynesian nominal rigidity model and estimate it by Bayesian methods to examine the dynamics of the key labor market variables and business cycles in Korea. The results show that unemployment rates are largely explained by technology shocks, which affect the labor demand side, as well as labor supply shocks. In addition, wage bargaining shocks originating from the bargaining process between firms and workers have non-negligible negative effects on output and employment growth, and careful measures need to be taken to limit their adverse effects.

• Journal of Family Relations
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• v.22 no.3
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• pp.131-153
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• 2017

Objective: This study aimed to examine the effects of adult children's marriage-delay on their parents' mental health. Furthermore, this study investigated how the influence of adult children's marriage-delay on parents' mental health could vary depending on the coresidence and employment status of the marriage-delayed adult children. Method: Two waves of Korean Longitudinal Study of Ageing (KLoSA) were used for the analyses. Multiple regression models were conducted with 2,938 Korean parents who had at least one child, regardless of gender (aged 33~44). Results: First, adult children's marriage-delay was related to lower levels of parents' life satisfaction. Second, the levels of parents' life satisfaction were low regardless of residing with their marriage-delayed adult children, and the parents who were not living with their marriage-delayed adult children showed lower levels of life satisfaction than parents living with marriage-delayed adult children. Third, only the parents with unemployed marriage-delayed adult children showed significantly higher levels of depression. However, the levels of parents' life satisfaction were low regardless of the employment of marriage-delayed adult children, and the parents of unemployed marriage-delayed adult children showed lower levels of life satisfaction than the parents of employed marriage-delayed adult children. Conclusions: It is necessary to consider the effects of marriage, employment and coresidence of adult children on their parents in order to enhance the mental health of the parents. Also, the effects of marriage-delay on intimate relationships, such as family dynamics, need to be explored more in further research.

• Journal of the Economic Geographical Society of Korea
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• v.5 no.2
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• pp.229-248
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• 2002

In the recent years the office sector or industry are recognized not only as a key economic activity and employment source in urban areas, but also as a factor for the changing urban spatial structure. This paper aims to review the research trends and future prospects on the office locations. The study starts with a survey of literatures by summarizing the most important previous studies on the office location research and by disclosing research deficits. And then general locational trends of office activities on the base on the different geographical scale and its current location dynamics including the influencing factors are discussed. Finally this study summarizes the outlooks on the future task within office location research.

• Nuclear Engineering and Technology
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• v.49 no.1
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• pp.92-102
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• 2017

The analysis of steam generators as an interface between primary and secondary circuits in light water nuclear power plants is crucial in terms of safety and design issues. VVER-1000 nuclear power plants use horizontal steam generators which demand a detailed thermal hydraulics investigation in order to predict their behavior during normal and transient operational conditions. Two phase flow field simulation on adjacent tube bundles is important in obtaining logical numerical results. However, the complexity of the tube bundles, due to geometry and arrangement, makes it complicated. Employment of porous media is suggested to simplify numerical modeling. This study presents the use of porous media to simulate the tube bundles within a general-purpose computational fluid dynamics code. Solved governing equations are generalized phase continuity, momentum, and energy equations. Boundary conditions, as one of the main challenges in this numerical analysis, are optimized. The model has been verified and tuned by simple two-dimensional geometry. It is shown that the obtained vapor volume fraction near the cold and hot collectors predict the experimental results more accurately than in previous studies.

• Korean Journal of Social Welfare
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• v.62 no.3
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• pp.5-29
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• 2010

This study examines the welfare dynamics in Korea under the scheme of National Basic Livelihood Protection Program(NBLP). Data are drawn from Korean Welfare Panel study 2005~2007. Main findings are summarized as follows. First, the exit probabilities show a declining tendency with time on welfare increases. If the exit probabilities indeed decline over time, the earlier years on welfare deserve more interest in the policy perspective. Moreover, the vast majority of recipients are long-termers. Further efforts are needed to increase self-sufficiency through providing genuine opportunity and necessary support for recipients. Second, out-of-poverty exit and out-of-system exit are quite different in their properties. The results from the multivariate analysis confirm that the dropouts through out-of-system exit are virtually the same with those who remain on welfare. These results imply that the government should not resort to the negative policy proposals such as time limit and strengthening sanctions. Third, several explanatory variables have anticipated effect on welfare exit probabilities. Age, education, health, marital status, the presence of children, employment status have a certain level of impact on exit, with the only exception of gender. Since the identification of the determinants can facilitate sensible targeting on the potential leavers, these results have some implications on policy proposals.

• Korean Journal of Social Welfare
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• v.67 no.4
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• pp.31-50
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• 2015

This study attempted to empirically investigate the determinants of poverty transition of the working poor with disabilities from a dynamic perspective. Analyses were conducted on the data from Panel Survey of Employment for the Disabled(PSED, Year 1-6), included the households with a disabled head of household. The working poor were defined as the household of which income fell below 120% of the absolute poverty line among the households just described. As results, The 6-year mean poverty rate for the working poor with disabilities included in the analysis was 31.4%, approximately three times of the poverty rate of the total population and the working poor with disabilities were found to have greater difficulty with poverty exit once having fell into poverty than all households living in poverty. And it was found that the economic activity factor was the key determinant of in-work poverty. In addition, employment of the working poor with disabilities did not lead straight to poverty exit, and the quality, rather than the status of, employment was the key determinant of poverty exit. The implications of the findings of this study are that it is essential to increase decent jobs, expand the social safety net of the working poor with disabilities and establish poverty reduction measures for each class of the working poor with disabilities to exit from poverty.

• 한국산학경영학회:학술대회논문집
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• 2005.11a
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• pp.1-9
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• 2005

Job search research has been criticized for failing to study the dynamics and change of the job search process. A lot of previous researches have used cross-sectional designs and treated job search as a static process. As a result, job search research has failed to examine how job seekers' behaviors change during the course of their search. This paper examined changes In job search behaviors(preparatory and active job search behavior, and job search intensity) and the effects of individual difference variables(self-esteem, self-efficacy, extroversion, agreeableness, conscientiousness, openness) on job search behaviors. Data were gathered from 404 university students who had not found employment at the time of beginning of second semester The results of t-test pairs indicated that job seeking students increased their preparatory job search behavior and active job search behavior, but didn't job search intensity. The results of multiple regression showed that self-efficacy had strong relationship with preparatory and active job search behavior, and job search intensity, but self-esteem had not any relationship with them. Among big-5 personality, extroversion had relationship with active job search behavior and job search intensity, and agreeableness only with job search intensity.

• Journal of the Korean Home Economics Association
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• v.38 no.9
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• pp.57-74
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• 2000

The major purpose of this study was to develop with priority given to the discourse on the correlation between interpersonal resources and home management behavior for family life satisfaction. So, this study was to identify the perception of equity in marital life, through which dynamic aspects is measured with family resource. Some of the major findings are as follows : The perception of equity in marital life show a significant difference by the state of employment and the degree of communication in couple. Housewives'home management behavior show a significant difference by the perception of equity in marital life. It appears that intra system dynamics elements explain housewives'home management behavior. From the Regression Analysis, the Model was found to be highly significant, accounting for 63% of the variances. Especially, housewives'family life satisfaction is influenced by the perception of daily life equity capable of evaluating each of a married couples'contribution and reward for family life lather than perception of psychological-emotional equity.