• Journal of Energy Engineering
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• v.26 no.2
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• pp.80-92
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• 2017

This paper attempts to estimate the diesel fuel demand function in Korea using panel data panel data of 16 major cities or provinces which consist of diesel demands, diesel market prices and gross value added from the year 1998 to 2015. I apply panel GLS(generalized least square) model, fixed effect model, random effect model and dynamic panel model to estimating the parameters of the diesel fuel demand function. The results show that short-run price elasticities of the diesel fuel demand are estimated to be -0.2146(panel GLS), -0.2886(fixed effect), -0.2854(random effect), -0.1905(dynamic panel) respectively. And short-run income elasticities of the diesel fuel demand are estimated to be 0.7379(panel GLS), 0.4119(fixed effect), 0.7260(random effect), 0.4166(dynamic panel) respectively. The short-run price and income elasticities explain that demand for diesel fuel is price- and income-inelastic. The long-run price and income elasticities are estimated to be -0.4784, 1.0461 by dynamic panel model, which means that demand for diesel fuel is price-inelastic but income-elastic in the long run. In addition I apply dummy variable model to estimate the effect of 16 major cities or provinces on diesel demands. The results show that diesel demands is affected 10 regions on the basis of Seoul.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2313-2315
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• 2002

본 논문에서는 3상 유도 전동기 고정자 전류 신호로부터 고정자 권선 고장에 대한 특성주파수를 효과적으로 검출하기 위한 고정자 전류 신호 해석 기법을 제시하였으며, 인위적인 턴 대 턴 고장 전동기의 부하실험을 통해 제안된 기법의 유효성을 확인하였다.

• Journal of the Korean Data and Information Science Society
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• v.28 no.5
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• pp.1055-1067
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• 2017

Most previous works to study for the depression of the disabilities in Korea have analyzed the repeated measured data of each individual under the mutually independent assumption. In this study, Korea Welfare Panel data of the disabilities surveyed additionally every three years are analyzed to detect the significant exploratory variables by the linear mixed models. A suitable correlation matrix is considered for the dependency of repeated measurement of each individual. The random effect to reflect the characteristics of the individuals as well as the fixed effect is included in the fitted linear mixed model. By the residual plot of the fixed effect model, the problem that the averages of residuals of each individual do not seem to be around zero is described. Further, the residual plot and the Q-Q plot coming from the selected final model are shown that the problem is modified well.

• Journal of the Society of Naval Architects of Korea
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• v.39 no.3
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• pp.28-40
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• 2002

Turbulent flows around two-dimensional wing sections in ground effect are analysed by incompressible RANS equations and a finite difference method. The Baldwin-Lomax algebraic turbulence model is used to simulate high Reynolds number flows. The main purpose of this study is to clarify the two-dimensional ground effect and its flow characteristics due to different ground boundary conditions, i.e., moving and fixed bottom boundary. As a first step, to validate the present numerical code, the computational result of Clark-Y(t/C 11.7%) is compared with published numerical results and experimental data. Then, NACA4412 section in ground effect is calculated for various ground clearances with two bottom boundary conditions. According to the computational results, the difference in the lift and moment simulated with the two bottom boundary conditions is negligible, but the drag force simulated by the fixed bottom is to some extent smaller than that by the moving bottom. Therefore, it can be concluded that the drag force measured in a wind tunnel with the fixed bottom could be smaller than that with the moving bottom.

• Journal of Labour Economics
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• v.35 no.3
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• pp.1-28
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• 2012

We measure a worker's analyzability by how correctly he grasps its causes when a problem occurs, comprehensiveness by how much he understand the overall process of his firm, and flexibility by how frequently unusual situations occur at his job. After controling firm-specific fixed of fandom effects, his age, tenure, position, and rank, the characteristics increase a worker's wage. A worker who grasps correctly the causes of problem is paid more by 5.2% than a worker who scarcely does. A worker who understands the overall process of his firm is paid more by 2.52% than a worker who understands roughly the process of his team or department. A worker whose job is mew one by one is paid more by 2.98% than a worker whose job is routine and repetitive.

• Journal of Labour Economics
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• v.43 no.1
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• pp.35-57
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• 2020

Using the Korea Labor and Income Panel Study(KLIPS), this study analyzes the effects of profit sharing on employer-provided training. The estimation results of the fixed effect model that controls for endogeneity show that the workers of profit-sharing firms have a 6.7%-6.8%p higher probability of receiving employer-provided training than the workers of firms without profit sharing. They also show that the workers of profit-sharing firms have a 3.3%p higher likelihood of having employer-provided OJT than their counterparts. The impacts of profit-sharing on employer-provided training appear consistently regardless of the estimation models and in the subsamples. These findings support the hypothesis that profit-sharing promotes employer-provided training.

• Journal of Labour Economics
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• v.40 no.2
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• pp.31-68
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• 2017

This study examined the moonlighting behavior in Korea, to which relatively less attention has been paid. Based on the wage earners of 25 to 65 year old married, the results show that about 1.4% of the sample have dual jobs, working very long hours, on average 60 hours for a week combining both the primary job and the secondary job. The results of the fixed effects logit model on the moonlighting participation indicate that the wage rate and the hours of work in the primary job have a negative effect on moonlighting participation while the insecurity of the primary job appears to lead to a higher probability of taking a secondary job. The results of the moonlighting hours analysis suggest that hours worked in the primary job have a negative effect on moonlight hours while the wage of the primary job does not appear to have any significant effect on moonlighting hours. Interestingly enough, the wage of the secondary job appears to have a negative impact on moonlighting hours, which might be very plausible considering the long working hours moonlighters are engaged in.

• The Journal of the Korea Contents Association
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• v.15 no.10
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• pp.214-224
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• 2015

The purpose of this study is to establish the social support system for social integration by analyzing the effect of multicultural experiences on multicultural perception and stereotype and the meditating effect of multicultural perception. The research result is summarized as follow : First, multicultural perception is differently influenced according to multicultural experiences. That is, multicultural experiences have found to have the positive effect on multicultural acceptance and the negative effect on rejection about other cultures or prejudice about other cultures. Second, the result which analyzed the effect of multicultural perception on stereotype has found that acceptance about other cultures doesn't have any effect on stereotype. However, it can be found that the prejudice and rejection about other cultures are verified to be the variables which have the positive effect on stereotype. Third, the result which analyzed the direct effect of multicultural experiences on stereotype and the indirect effect through multicultural perception has found that multicultural experiences don't have any direct effect on stereotype, but do have the indirect effect through multicultural perception. With the help of information technology.

• Microbiology and Biotechnology Letters
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• v.9 no.3
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• pp.165-171
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• 1981

The penicillin amidase from Escherichia coli (ATCC 9637) was immobilized by entrappment in gelatin and DEAE-cellulose mixture cross-linked with glutaraldehyde, and the kinetics in a differential column reactor was studied. The optimal operating condition of a differential reactor was reasonably met when the enzyme loading was 1g, and 30 mM substrate solution in 0.1 M phosphate buffer (pH 8.0) was fed at flow rate 4$m\ell$/min and 4$0^{\circ}C$. The optimal pH and temperature were found to be 8.0 and 55$^{\circ}C$, respectively. The Michaelis-Menten constant was 4.8 mM while the maximum velocity was 308 units/g of the immobilized enzyme under the condition of the differential reactor. The effect of substrate inhibition disappeared in the immobilized enzyme preparation. The differential reactor was proved to be good for studying the true kinetics since the pH drop and the external diffusional resistance could be eliminated.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.273-279
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• 2016

The purpose of this study was to examine the mediating effects of permissiveness of sexual violence on the relationship between gender role stereotypes and experience of sexual violence. The survey for this study was administered to 408 (male, 127, female, 281) out of the 600 university students residing in Jeju with the inventory of gender role stereotypes and experience of sexual violence in (conjunction with the) permissiveness of sexual violence scale. The results of this study were as follows: First, as a result of the correlation analysis, gender role stereotypes and experience of sexual violence were positively correlated with permissiveness of sexual violence. Second, the relationship analysis by Structural Equation Modeling demonstrated that permissiveness of sexual violence completely mediated the relationship between stereotypes of gender role and experience of sexual violence. Permissiveness of sexual violence was the most significant factor giving rise to sexual violence in dating. In the investigation of the structure of the equation coefficients and path-mediated effects, the standardized path coefficients of influence in this study, viz. gender role stereotypes to permissiveness (29, p=.000) of sexual violence and permissiveness of sexual violence to the experience of sexual violence (42, p=.000), were found to have an impact. In an indirect effect on the effectiveness of the parameters showed in gender role stereotypes and experience of sexual violence (11, p=.01), direct effects were demonstrated from stereotypes of gender role to permissiveness of sexual violence (28, p=.000) and from permissiveness of sexual violence to experience of sexual violence (40, p=.000). In the end, this implies that gender role stereotypes does not influence permissiveness of sexual violence directly, but indirectly by mediating the experience of sexual violence. Therefore, the implication of this study is that gender role stereotypes and permissiveness of sexual violence need to be reduced, so that sexual violence can be prevented. In other words, a higher awareness of gender equality will lower permissiveness of sexual violence and this, in turn, will also prevent sexual violence.