• Journal of Korea Technology Innovation Society
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• v.21 no.4
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• pp.1508-1535
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• 2018

Employment in enterprises is a consecutive decision-making process based on the results of their innovative activities and it is necessary to consider this relationship as well explicitly in an analysis of the employment performance through technological innovation. Based on this critical mind, this study would analyze the structural relationships among enterprises' innovative activities, the performance of technological innovation, a compensation system and the creation of employment, reflecting the correlation of the process of the actual technology management performed simultaneously, utilizing the seemingly unrelated regression(SUR) model to estimate a simultaneous equation in addition to analyzing the relationship between technological innovation and the effect on employment with the ordered logit model to estimate a single equation as in the preceding studies. As a result of the analysis, a structural relationship could be found out, in which the execution of the compensation system would increase the performances of technical development and technology commercialization, which in turn, accelerates enterprises' employment. Especially, it is judged that enterprises' employment performance increases when technological innovation is managed from a process perspective in that the commercialization performance, as well as technical development, acts as a kind of hurdle in the effect on employment.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.3
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• pp.222-227
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• 2007

Formation of freak waves is studied in deep water from transient wave packets propagating on current. Those waves are obtained by means of dispersive focusing. This process is investigated by solving both linear and nonlinear equations. The role of nonlinearity is emphasized in this interaction.

• Korea Trade Review
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• v.44 no.2
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• pp.51-62
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• 2019

This study predicts the future world seaborne trade volume with econometrics methods using 23-year time series data provided by Clarksons. For this purpose, this study uses simple regression analysis, exponential smoothing method and seemingly unrelated regression model (SUR Model). This study is meaningful in that it predicts worldwide total seaborne trade volume and seaborne traffic in four major items (container, bulk, crude oil, and LNG) from 2019 to 2023 as there are few prior studies that predict future seaborne traffic using recent data. It is expected that more useful references can be provided to trade related workers if the analysis period was increased and additional variables could be included in future studies.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.6
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• pp.180-191
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• 2020

This study analyzes factors that affect average daily travel time budgets, using the Time Use Survey data from 1999 to 2014 in Seoul. We first developed multivariate regression models for travel time from each year, considering demographic and socio-economic variables as well as non-home activity time. The model results showed that household and personal characteristics and non-home activities significantly affect travel time, and their effects are different over time. In addition, we developed seemingly unrelated regression (SUR) models for time allocation for non-home activity and travel, considering their correlations, and explanatory variables were compared over time. Overall, demographic and socio-economic variables significantly affect travel time as well as non-home activity time.

• Journal of the Economic Geographical Society of Korea
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• v.14 no.3
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• pp.307-324
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• 2011

The culture industry is viewed as a driving industry in the 21th century. Korea has experienced the rapid growth rate of the cultural industry in terms of sale amounts for the period of 2004-2009. The purposes of this study are to analyze the spatial pattern of the cultural industry and to empirically examine the effect of municipalities' cultural industries on regional economy using SUR model. The major findings are as follows: First, cultural industries are concentrated in the capital region and several metropolitan areas. Secondly, the estimated result of SUR model shows that there is inter-relationship between cultural industry and regional economy. The effect of the cultural industry on GRDP is that the cultural industry increased 1%, GRDP increased by 0.46%. In turn, GRDP increased 1%, cultural industry increased by 0.75%. Thirdly, the elasticity of the cultural industry on GRDP is much higher than that of labor or capital stock, showing that the cultural industry has a more powerful influence on its regional economy. Fourth, the elasticity of the cultural industry on GRDP of Gun is higher than that of shi, indicating that it is rational for Gun to develop strategies to promote competitive power of the cultural Industry for regional economic growth.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.35-39
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• 2011

토양과 식물의 잎에서 일어나는 증발산은 주로 증발접시, 침루계 등을 이용하여 실측하거나 에디 공분산, Bowen 비 등을 이용하여 경험적으로 측정할 수 있으나, 이러한 지점별 실측 자료는 공간적인 변동성이 큰 수문기상인자 특성상 지역적인 대표값으로 적용하는 데 어려움이 따른다. 본 연구에서는 이러한 기존 증발산 관측 방법의 단점을 보완하고자 인공위성 영상자료를 기반으로 한 원격탐사 기법을 이용하여 Penman-Monteith (PM)와 Priestley-Taylor (PT) 공간 증발산 산정 모형을 적용, 우리나라 증발산의 시공간적인 분포를 산정하였다. Terra 인공위성에 탑재된 Moderate Resolution Imaging Spectroradiometer (MODIS)로부터 제공되는 위성 영상 자료를 이용하여 기존에 연구된 증발산 모형을 이용하여 증발산을 산정하고 이를 상호 비교함으로써 우리나라에 대한 적용성을 검토하였다. 본 연구의 결과는 토양 및 식생이 소비하는 물의 양을 보다 정확하게 시공간적으로 파악하여 정부 차원의 수자원 관리 계획 수립에 유용하게 이용될 것이다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.72-80
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• 2014

This study is to estimate a demand of coffee in Korea. And based on assumed data, this study is to investigate price elasticity, income elasticity and cross-price elasticity of coffee demand. The data used in this study is the household income and expenditure survey micro data (2003~2012) provided by the National Statistical Office. And LA/AIDS model and SUR method were utilized in order to forecast coffee demand. As a result, price elasticity and income elasticity are found to be correspond with economic theory as they were assumed to -0.259, 0.455 respectively. Meanwhile, it indicated characteristic of essential good by showing negative (-) income odds ratio estimate. When it comes to cross-price elasticity of coffee and cigarette, it was found to be a complementary relation as its cross-price elasticity was assumed to -0.121. Besides, it was found that male consume more coffee than female, while people in their age of 50s consumes mostly. In conclusion, this study suggests necessity of reconsidering coffee as important goods when Consumer Price Stabilization Policy is determined, as coffee shows characteristic of essential goods which is inelastic.

• Environmental and Resource Economics Review
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• v.30 no.2
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• pp.207-235
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• 2021

This paper examines the effects of ambient air pollution by ozone and particulate matter on traveling by mode of transport. We estimate the SUR model of travel time by different modes of transportation using individual level data of travel diaries. We find that, as air pollution levels rises, traveling by privately-owned vehicles increases but traveling by bus decreases. Our results also show that, when an air quality alert is issued, bus traveling increases in an effort to reduce pollution levels, but traveling by own car does not change and traveling by train declines. This suggests that alert programs may not be highly effective in reducing air pollution emissions from vehicles because voluntary switching to public transportation induced by air quality alerts is outweighed by individual effort of avoiding exposure to pollution.

• Journal of the Economic Geographical Society of Korea
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• v.12 no.2
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• pp.142-158
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• 2009

The purpose of this paper is to identify determinants of regional export in Korea using the interregional input-output table and SUR(Seemingly Unrelated Regression) model. Regional exports are classified into four groups; intraindustry intraregional export, interindustry intraregional export, intraindustry interregional export and interindustry interregional export. Labor productivity, scale economies, market size, and international trade volumes have positively influenced regional exports while the interregional distances having a negative effect on them. These results imply that it is necessary to operate regional strategies to enhance productivities and market size and to reduce transportation and distribution costs for revitalize a regional economy by increasing regional exports.

• Journal of Korean Society of Transportation
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• v.32 no.2
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• pp.83-92
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• 2014

Weather condition is one of the crucial factors affecting travelers' mode choice. Nevertheless, there are numerous indefinite traffic phenomena under various weather conditions. This study was conducted to verify the hypothesis that transit riderships decrease as precipitation increases. To clarify the relationship between precipitation and transit ridership, a seemingly unrelated regression model was employed with data such as daily precipitation and daily transit riderships of 3 transit modes (bus, metro, and shuttle bus) collected in Busan for recent 24 months. The estimation results show that transit riderships decreased as the daily precipitation increased when the daily precipitation is greater or equal to 10mm/day (0.169%, 0.101%, and 0.172% reduction in bus, metro, and shuttle bus riderships, respectively, when the daily precipitation increased by 1mm). When comparing the impact of precipitation on transit riderships by modes using a cross-equation parameter restriction test, the decrease in metro ridership is relatively insensitive to the change in precipitation. However, the negative coefficient of precipitation in the metro ridership estimation model indicates that the transit users in Busan may alter their mode to taxi or automobile and/or may give up the trip itself in bad weather condition.