• Environmental and Resource Economics Review
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• v.21 no.3
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• pp.519-542
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• 2012

In this paper, we empirically analyzed whether carbon leakage really happened in EU by comparing before and after the period of EU ETS. We regarded foreign direct investment outflows as indicator of carbon leakage and analyzed panel regression between production cost including environment cost and this FDI variable. Also we consider foreign market potential to analyze market oriented FDI. According to this analysis, carbon leakage was observed in some models for manufacturing industry. However carbon leakage did not prove consistently in a variety of models and it is hard to speak carbon leakage was happened in EU ETS. Notwithstanding relatively short time series of data, in the view of the fact that carbon leakage was tested in some models, Korea also should keep in mind the possibility of carbon leakage and design emission trading scheme.

• Journal of Labour Economics
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• v.34 no.1
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• pp.71-101
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• 2011

Using an establishment-level panel data drawn from the employment insurance administrative DB, this study investigates the relationship between elderly and youth employment in Korea. The primary focus of interest is whether or not the ageing of workforce and an increase in elderly employment have negative impacts on youth employment. In the regression using the full sample, we find the evidence that a movement in elderly employment and ageing workforce are positively related to youth employment. However, we do not find consistent evidence of the positive impact of the elderly employment on youth employment in the estimations using sub-samples divided by various criteria.

• The Korean Journal of Applied Statistics
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• v.30 no.6
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• pp.957-981
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• 2017

A generalized linear mixed model is an extension of a generalized linear model that allows random effect as well as provides flexibility in developing a suitable model when observations are correlated or when there are other underlying phenomena that contribute to resulting variability. We describe maximum likelihood estimation methods for logistic regression models that include random effects - the Laplace approximation, Gauss-Hermite quadrature, adaptive Gauss-Hermite quadrature, and pseudo-likelihood. Applications are provided with social science problems by analyzing the effect of mental health and life satisfaction on volunteer activities from Korean welfare panel data; in addition, we observe that the inclusion of random effects in the model leads to improved analyses with more reasonable inferences.

• Journal of the Earthquake Engineering Society of Korea
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• v.5 no.1
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• pp.37-44
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• 2001

면진기술은 주로 저층 구조물의 내진설계에서 적용되는 방법으로 건물과 기초사이에 면진장치를 설치하여 상부로 전달되는 지진하중을 효과적으로 감소시킨다. 그러나 이 방법은 중.고층 구조물에 그대로 적용하기에는 여러 가지 기술적 문제가 따르므로, 구보물의 중간층 일부를 분리시켜 상부로 전달되는 지진력을 감소시킬 수 있을 것이다. 본 노문에서는 저층 뿐만 아니라, 중.고층 정형구조물의 주상복합건물과 같은 비정형 구조물에 대하여 구조물의 중간층 일부를 비선형 면진장치로 면진시키고 그 효과를 분석하였다. 이러한 중간층 면진 구조물의 경우, 고정기초 구조물에 비하여 적은 층간변위나 층전단력이 발생하였으며, 특히 주상복합건물에서 상당한 효과를 볼 수 있었다.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2003.09a
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• pp.59-59
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• 2003

목적 : 환자의 호흡에 의한 움직임 및 부정확한 환자 자세 setup 때문에 3 차원 전신 정위 방사선치료,3 차원 입체조형 방사선치료 IMRT와 같은 방사선 치료기술에서 병소에 대한 정확한 표적 위치측정은 매우 어려운 실정이다. 그러므로 본 연구는 방사선 치료시 환자의 움직임을 최대한 고정시켜 줄 수 있으며 환자 자세에 대한 setup 오차를 감소시키고 환자 전신에 산재한 병소의 위치를 좌표화할 수 있는 전신 정위 프레임 제작과 제작한 프레임에 대한 고정효과 및 재현성을 나타내는 환자 자세의 setup 오차를 평가하는데 있다. 재료 및 방법 : 자체 제작한 전신 정위 프레임 구조는 CT 영상 촬영 가능성에 중점을 두고 병소 표적의 좌표실현 및 환자체형에 따른 다양성 그리고 프레임에 대한 견고성 및 안정성 확인에 초점화하여 제작하였다. 이렇게 제작된 전신 정위 프레임에 대한 방사선 투과율 측정 실험과 CCTV 카메라와 DVR(Digital Video Recorder)를 이용해 환자 자세 변화에 대한 영상을 획득하여 matlab으로 구현한 오차분석용 프로그램으로 환자 외부자세에 대한 오차 비교 평가하고 CT 촬영에 의한 가상표적 위치측정 실험을 수행하였다. 또 한 고정벨트 추가 사용으로 인한 환자의 고정효과 정도를 살펴보았다. 결과 : 제작된 전신 정위 프레임에 대한 방사선 투과율은 마그네트론 10, 21 MeV의 에너지에서 95, 96% 의 투과율이 측정되었고 30 $^{\circ}$. 60 。각도의 경사로 빔이 전달될 때는 90.3, 94.4% 가 측정되었다. CCTV 카메라를 이용하여 흉부 및 복부의 움직임을 촬영한 영상을 Matlab프로그램으로 구현한 오차분석 프로그램을 적용한 결과, 환자 자세에 대한 오차의 평균값은 흉부의 lateral 방향에서는 3.63$\pm$1.4 mm, AP 방향에서는 2.1$\pm$0.82 mm이었다. 그리고 복부의 later의 방향에서는 7.0$\pm$2.1 mm, AP 방향에서는 6.5$\pm$2.2 mm 이었다. 또한 표적 위치측정을 위해서 환자의 피부에 임의의 가상표적을 부착하고 CT 촬영한 영상결과, 프레임으로 가상표 적에 대한 위치를 정확히 파악할 수 있었다. 결론 : 제작된 프레임을 적용하여 방사선투과율 측정실험, 환자 외부자세에 대한 오차 측정실험, 가상표적 위치측정 실험 등을 수행하였다. 환자 외부자세에 대한 오차 측정실험 경우, 더 많은 Volunteer를 적용하여 보다 정확한 오차 측정실험이 수행되어야 할 것이며 정확한 표적 위치 측정실험을 위해서 내부 마커를 삽입한 환자를 적용한 임상실험이 수행되어야 할 것이다. 또한 위치결정에서 획득한 좌표값의 정확성을 알아보기 위해서 팬톰을 이용한 방사선조사 실험이 추후에 실행되어져야 할 것이다. 그리고 제작된 프레임에 Rotating X선 시스템과 내부 장기의 움직임을 계량화하고 PTV에서의 최적 여유폭을 설정함으로써 정위 방사선수술 및 3 차원 업체 방사선치료에 대한 병소 위치측정과 환자의 자세에 대한 setup 오차측정 결정에 도움이 될 수 있을 것이라고 사료된다.

• Journal of Environmental Impact Assessment
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• v.25 no.5
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• pp.307-318
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• 2016

This research examines the impacts of urban population growth on per capita $CO_2$ emissions with particular focus on the interaction effect between urbanization and income levels. Employing the Panel Fixed Effects model together with the Pooled LS and Panel GLS models, the research reported here analyzes the relevant data on 84 countries. The statistical results show a nonlinear(an inverted-U) relationship between urbanization and per capita $CO_2$ emissions; that is, while the urban agglomeration leads to increases in per capita $CO_2$ emissions for low income countries, this adverse impact does not hold true for high income countries. The research findings can contribute to addressing broad issues of urban compactness and patterns of energy consumption that should be considered by those concerned about the sustainable urban development.

• Journal of the Korean Geotechnical Society
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• v.29 no.6
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• pp.63-75
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• 2013

Inclined Earth Retaining Structure Method (IER Method), was developed in order to improve the mechanical properties of the existing earth retaining method. IER consists of two supports, which are front and back supports. In the IER method, back support is very effective for the reduction of the earth pressure acting on the front support. In this study, the effects of back support and fixing conditions of lower ends of supports are analysed by laboratory model tests in clay. The test results show that back support reduces the Leteral displacement of IER effectively, and according to the results the effect of interval and fixing condition of back support was analysed.

• Journal of the Korea Convergence Society
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• v.11 no.12
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• pp.187-197
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• 2020

In this study, how international diversification of domestic companies increases corporate profits and increases the dividend income of paid-in capital investors, who provided the basis for corporate business activities in the process of distributing profits. I tried to find out if it had an effect. An empirical analysis was conducted using a fixed-effect model for companies with settlements at the end of December listed on the domestic securities market from 2011 to 2018. It was confirmed that the higher the level of international diversification of individual companies, the higher the company's dividend payout ratio and dividend yield. This means that companies can steadily expand corporate profits and dividend yield of shareholders by securing new overseas markets through international diversification, it can be seen that a company's international diversification strategy can contribute to the increase of corporate value by increasing the company's dividend payout ratio by increasing dividendable profit.

• Journal of the Economic Geographical Society of Korea
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• v.20 no.1
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• pp.84-104
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• 2017

In this study, we divided Gyeonggi-do into Northern, Southern, Western, and Eastern Parts and found out fiscal variables which affected regional economic growth of each Part differentially. And we drew the strategy for economic growth of each Part. After we found out the variables which affected regional economic growth using fixed-effect model, we carried out causality test to determine whether a specific fiscal variable caused economic growth. In the Eastern Part, local tax revenues had a significant effect on the economic growth. Total expenditures, current expenditure in the Southern Part and social welfare expenditure, expenditure on industries, current expenditure in the Northern Part had noticeable effects on economic growth respectively. And we calculated multipliers of fiscal variables to compare the magnitudes of effects among these Parts.

• Economic Analysis
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• v.27 no.3
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• pp.33-60
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• 2021

This study estimates the fiscal multiplier using Input-Output table panel data from year of 2010 to 2018. Considering the endogeneity of the government expenditure, this study uses the share of government expenditure by sector in the initial period as an instrument variable. The estimation from the panel fixed effect instrumental variables model shows that the estimate for the current period of government expenditure is 1.15~1.22 and the estimate for the cumulative multiplier is 1.23~1.32 depending on the method of controlling time trend. Since the general equilibrium effect absorbed by the time-fixed effect in the estimation equation, the estimated multiplier in this study may be different from the multiplier of the economy as a whole. The general equilibrium effect depends on the response of monetary policy, changes in tax policy, and interaction between sectors.