• Environmental and Resource Economics Review
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• v.28 no.4
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• pp.497-526
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• 2019

The importance of "decoupling" to maintain economic growth and reduce greenhouse gases is emerging as the world has been mandated to reduce greenhouse gases since the 2015 Paris Agreement. This study covered 63 countries from 1980 to 2014 and analyzed the main characteristics and causes of decoupling phenomenon between economic growth and carbon emissions. In this study, the degree of decoupling was measured every five years. The analysis found that the decoupling rate of OECD countries and countries with large incomes was high, and that the decoupling phenomenon has accelerated worldwide since the 2000s. However, the degree of decoupling was different depending on the national characteristics. According to the results of dynamic panel model, the growth rate of manufacturing and the proportion of exports hampered decoupling, while the proportion of human capital and renewable energy had a positive effect on decoupling. Also income had a inverse U-shape non-linear effect on decoupling.

• Korea Real Estate Review
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• v.28 no.3
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• pp.53-64
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• 2018

OECD countries have been stimulating private pensions instead of public pensions because the financial stability of public pensions has been threatened by the aging population. Korea, which has the fastest aging population in the world, has been following the recommended policies of major countries. Unlike major economies, however, most of Korea's household assets are composed of real estate assets. Due to the economic and social importance of real estate assets in Korea, the wealth effect of real estate has been used as a major tool in macroeconomic policy. This study analyzed the effect of real estate value changes on the contribution of private pensions (personal pension + retirement pension). Utilizing a two-way, fixed effect model with the balanced panel data of the National Survey of Tax and Benefit, empirical results presented that the private pension contribution increased by 0.171% when the value of real estate increased by 1%. Thus, real estate value changes were analyzed as positive for retirement preparation through private pension. These results suggested that if the real estate market would shrink in the future, consumption would decrease, and the degree of preparation for retirement might be smaller.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.771-783
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• 2022

In this study, the feasibility of alternative tractor Roll Over Protective Structure (ROPS) designed to evaluate conditions required for testing was confirmed. In accordance with Organization for Economic Cooperation and Development (OECD) code 4, the required load energy of the tractor ROPS was determined. First, the tractor ROPS test was performed and a repeated test was performed using a simplified ROPS as an alternative tractor ROPS. The test procedure is first rearward, second lateral, and last forward based on ROPS. The load test device consists of a load cell that measures force and a LVDT that measures deformation. Precision was confirmed by calculating the relative standard deviation of the simplified ROPS repeated test. Accuracy was analyzed by calculating the mean relative error between the mean measured values in the simplified ROPS test and the tractor ROPS test. As a result, the relative standard deviation was less than 2.5% for force and 3.3% for maximum deformation overall, showed the highest precision in lateral load. The mean relative error value for force measured at the lateral load of simplified ROPS was 0.5%, showing the highest accuracy. In the front load test, the mean relative error of maximum deformation was 20.5%, showing the lowest accuracy. The mean relative error (MRE) was high in the forward load test was because of structural factors of the ROPS. The simplified ROPS model is expected to save money and time spent preparing tractors.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.468-474
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• 2019

Korea had the highest accident rate among OECD countries in 2018, with 8.4 per 100,000 population, ranking 4th among 35 countries. In addition, the accident rate of traffic with children and the elderly was also high. This study reviewed the relevant literature and analyzed the traffic-accident analysis system. Customized traffic safety facilities were developed. In addition, by measuring the visibility of the traffic safety facilities by installing a test bed, this study measured the forward driving frequency and vehicle driving speed while driving. As a result of applying the "pedestrian pedestrian model" collision test model, the possibility of serious injury after installing the facility was reduced greatly to 4.6%. In this study, the visibility of traffic safety facilities and the effect of reducing the traffic speed were verified through test beds. Recognizing traffic safety facilities will reduce traffic accidents.

• Korea Real Estate Review
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• v.24 no.1
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• pp.39-52
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• 2014

This study examines the degree of global co-movement & spillover effect among the housing price of ten major countries of OECD including Korea, based on the 3 hypothesis. The data used in this study is quarterly house price index of OECD countries from 1975 to 2012. VAR model is used to analyze the co-movement, and Granger causality methodology is used for the analysis of Spillover Effect. It is found that entire period of study is that the global house prices showed the co-movement, but the coefficient was weak. Since 2008 global financial crisis, the co-movement increased significantly and the adjusted R-square of this model increased 78% compared to the entire period (1975-2012). In general, all hypotheses in this study were significant, and the common shock hypothesis were most significant. In case of Korea, the degree of co-movement was weak compared to the other countries and spillover effect was independent since 2008.

• Korean Chemical Engineering Research
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• v.54 no.5
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• pp.621-629
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• 2016

Recently, the researches on quantitative structure activity relationship (QSAR) for describing toxicities or activities of chemicals based on chemical structural characteristics have been widely carried out in order to estimate the toxicity of chemicals in multiuse facilities. Because the toxicity of chemicals are explained by various kinds of molecular descriptors, an important step for QSAR model development is how to select significant molecular descriptors. This research proposes a statistical selection of significant molecular descriptors and a new QSAR model based on partial least square (PLS). The proposed QSAR model is applied to estimate the logarithm of partition coefficients (log P) of 130 polychlorinated biphenyls (PCBs) and lethal concentration ($LC_{50}$) of 14 PCBs, where the prediction accuracies of the proposed QSAR model are compared to a conventional QSAR model provided by OECD QSAR toolbox. For the selection of significant molecular descriptors that have high correlation with molecular descriptors and activity information of the chemicals of interest, correlation coefficient (r) and variable importance of projection (VIP) are applied and then PLS model of the selected molecular descriptors and activity information is used to predict toxicities and activity information of chemicals. In the prediction results of coefficient of regression ($R^2$) and prediction residual error sum of square (PRESS), the proposed QSAR model showed improved prediction performances of log P and $LC_{50}$ by 26% and 91% than the conventional QSAR model, respectively. The proposed QSAR method based on computational toxicology can improve the prediction performance of the toxicities and the activity information of chemicals, which can contribute to the health and environmental risk assessment of toxic chemicals.

• Journal of Information Technology Services
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• v.7 no.2
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• pp.59-75
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• 2008

Despite our extensive understanding on the Internet business and widely understood first-mover advantage. it is not clearly answered yet whether an internet firm can enjoy the first-mover advantage in the new environment of the Internet. This is mainly because the Internet marketplace itself has a complex combination of various business models, ranging from a simple channel-extension to a whole new business model. Based on new theoretical development on the first-mover advantage, we empirically test whether being an early mover in the Internet environment materially affects firm performance, using clickstream data from Korea where broadband Internet installation is ranked as top among OECD countries. Our results show the effectiveness of first-mover advantage on the web does not exist, regardless of its business model and competitive environment. This result expands our understandings on the e-business, not to mention of the real feature of first-mover advantage.

• Journal of Environmental Impact Assessment
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• v.5 no.2
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• pp.79-91
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• 1996

In Chapter 40, "Information for decision-making", of Agenda 21, it was Slated that, "indicators of sustainable development need to be developed to provide solid bases for decision-making at all levels and to contribute to a self-regulating sustainability of integrated environment and development systems." Sustainable development has been defined as "development that meets the needs of the present without compromising the ability of future generations to meet their own needs", An indicator that measures sustainability should therefore focus on this definition. One of the most widely used frameworks for environmental indicators is the Pressure-State-Response model proposed by the OECD. And we introduced the the Driving force-State-Response framework, the adaptation of Pressure-State-Response model, for UN sustainable development indicators. Therefore, in our country, indicators for sustainable development should be developed by using the DSR framework.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05a
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• pp.635-640
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• 1998

Thermal fluid mixing behavior during a postulated medium-size hot leg break loss of coolant accident is analyzed for the international comparative assessment study on pressurized thermal shock (PTS-ICAS) proposed by OECD-NEA. The applicability of RELAP5 code to analyze thermal fluid mixing behavior is evaluated through a simple modeling relevant to the problem constraints. Based on the calculation result, the onset of Thermal stratification is investigated using Theofanous's empirical correlation. Sensitivity calculations using a fine node model and crossflow model are also performed to evaluate the modeling capability on multi-dimensional characteristics related to thermal fluid mixing.

• Proceedings of the Korea Information Processing Society Conference
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• 2015.04a
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• pp.641-644
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• 2015

우리나라는 지난 40년간 급속한 경제 성장의 과정에서 에너지 소비가 급증하고 있으며, 이로 인해 온실가스 배출량은 1990년~2005년 사이 두 배 이상 증가하였고, 이는 OECD 국가 중 가장 높은 증가율이다. 2차 오염물질인 오존은 1990년부터 2012년까지 연평균 3% 상승하고 있으며, 반복 노출 시 폐에 피해를 줄 수 있는 오염 물질로 예방 대책이 필요하다. 이를 위해 본 논문에서는 계절성 특성을 지닌 오존농도 시계열 데이터를 바탕으로 SARIMA 모형을 활용하여 예측 모형을 구축 하였다.