• Journal of Korea Port Economic Association
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• v.30 no.2
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• pp.133-143
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• 2014

The paper uses a panel gravity model to analyse the determinants of export via Gwangyang port for the period from 2000-2012. The gravity model includes export via Gwangyang port, GDP and population of trading partners, the distances between Korea and its partners, and Korea-ASEAN FTA dummy. Hausman test shows up which one is exactly appropriate between random effect estimation and fixed effect estimation to use panel dataset. It depends on whether or not existence or nonexistence of the correlation between unobserved omitted factors and variables. Fixed effect estimation is suitable for this paper by the rejection of null hypothesis. An Empirical analysis of this paper shows GDP influences positive effects and distance influences negative effects to Gwangyang port trading partners. In addition, the results strongly supported the effects of Korea-ASEAN FTA on the growth of Gwangyang port export.

• Korean Journal of Social Welfare Studies
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• v.40 no.2
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• pp.313-335
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• 2009

The objective of this study was to examine the association between participation in volunteer activities and self-esteem among adolescents. This study used data from the wave3-5(2005-2007) of Korean Youth Panel Study(KYPS). This study analyzed data of 3,449 second grade middle school students cohort. Fixed effects model using Proc GLM procedure in SAS was adopted to examine association between participation in volunteer activities and self-esteem among study participants. The results show that life satisfaction, appearance stress, relationship with parents, relationship with siblings, grades, relationship with teachers, and relationship with friends were significantly associated with self-esteem. Volunteer activities participation was associated with increased level of self-esteem.

• Journal of Korean Society of Forest Science
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• v.104 no.1
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• pp.111-116
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• 2015

The purpose of this study was to evaluate mixed model of dbh-height relation containing random effect. Data were obtained from a survey site for Quercus variabilis in Gangwon region and remeasured the same site after three years. The mixed model were used to fixed effect in the dbh-height relation for Quercus variabilis, with random effect representing correlation of survey period were obtained. To verify the evaluation of the model for random effect, the akaike information criterion (abbreviated as, AIC) was used to calculate the variance-covariance matrix, and residual of repeated data. The estimated variance-covariance matrix, and residual were -0.0291, 0.1007, respectively. The model with random effect (AIC = -215.5) has low AIC value, comparison with model with fixed effect (AIC = -154.4). It is for this reason that random effect associated with categorical data is used in the data fitting process, the model can be calibrated to fit repeated site by obtaining measurements. Therefore, the results of this study could be useful method for developing model using repeated measurement.

• Journal of Korea Technology Innovation Society
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• v.21 no.2
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• pp.663-683
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• 2018

This study aims to analyze the effectiveness of R&D tax credit for SMEs. We surveyed to collect the information on firm's financial statements and R&D tax credit during 2014-2016, and implemented fixed effect model, random effect model and panel negative binomial model. The results show that the effect of R&D tax credit is 5.3 times larger in terms of R&D expenditure and 4.3 times bigger in terms of number of researchers than that of R&D subsidy. In addition, the effect of tax credit on non-metropolitan area companies is higher than that in the metropolitan area. Based on these results, we suggests three ways to improve the R&D tax incentive system for SMEs; To convert unused R&D tax credit of the start-ups to tax points, to exempt the minimum tax rate on R&D expenditure in equipment, and to unify the operation of various R&D tax credit institution.

• Journal of Digital Convergence
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• v.17 no.11
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• pp.1-7
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• 2019

This study analyzed the effects of labor aging on labor productivity using panel statistics of 16 local governments from 1995 to 2017. The aging of the labor force, defined as the proportion of workers aged 60 or older in total employment, in the results of the panel regression analysis considering regional fixed effects and various adjustment variables, has a very consistent and significant negative effect on labor productivity. For every 1% increase in aging, labor productivity decreases by about 0.14 ~ 0.20%. In addition, the per capita capital stock and human capital considered as adjustment variables contributed to the increase of labor productivity, and the unemployment rate, which is a proxy variable of the economic fluctuation, has a significant negative effect on labor productivity as expected. The coefficient of the industrial structure, which represents the share of the service industry in the whole industry, was positive, but is not significant. The results of this study suggest that the design and construction of economic and educational policies that can maintain and expand human capital are necessary to curb the reduction in labor productivity expected by the aging workforce.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.1
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• pp.57-65
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• 2022

Gyeongsangnam-do has been operating Bravo-taxi, a Gyeongnam-type DRT using taxi vehicles, since 2017 to guarantee the right of mobility for residents who live in areas lacking public transportation. This research investigated and analyzed changes in users' awareness over two years from beginning of Bravo-taxi operation in Gyeongsangnam-do, which started operating Bravo-taxis in 2017, targeting sites lacking public transportation. Through this study, the positive effects of taxi-type DRT were confirmed, such as improving the mobility of residents in areas underprivileged by public transportation, reducing required time for trips, and increasing preference for Bravo-taxis compared to existing buses. On the other hand, problems with the current Bravo-taxi system were also identified. In some areas, it was found that there were not enough coupons for Bravo-taxis, or in the case of Bravo-taxis operating at fixed times, the user's desired time and operating time did not match, resulting in lower satisfaction. The results of this research are expected to be utilized as basic data for service continuity of taxi-type DRT in operation by other local governments.

• Proceedings of the KSRS Conference
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• 2007.03a
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• pp.105-108
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• 2007

차량에 부착된 회전식 레이저 스캐너는 360도로 회전하면서 데이터를 취득하기 때문에 고정식 레이저 스캐너에 비해 더 광범위하고 정확한 3차원 데이터를 획득하고 생성할 수 있다. 그러나 레이저 데이터 자료는 표적까지의 거리와 취득 당시의 스캐너의 각도로만 구성되어있기 때문에 이를 사용하기 위해서 이 데이터들을 일련의 좌표변환과정을 거쳐서 3차원 직교좌표계로 변환시킨다. 이 논문의 목적은 회전식 레이저에서 획득된 데이터를 DEM화하고，DEM영상의 밝기값， 즉 높이값을 이용하여 도로변을 주위의 사물과 분리하여 추출하는 것에 있다. 도로면은 일반적으로 주위의 사물에 비해 그 높이가 낮고 고르게 분포되어 있다고 가정한다. 그렇기 때문에 이 도로면의 높이를 대표할 수 있는 적절한 임계값을 찾을 수 있다면 도로면의 분리 또한 가능하다. 도로면의 추출을 위해 제안된 방법은 취득된 레이저 데이터를 일정 간격의 높이로 나누고 그에 대한 히스토그램을 구한 후, 가장 많은 빈도수를 나타낸 지역의 값을 염계치로 설정하는 방법과，레이저 스캐너가 지표면을 향할 때의 각도，즉 270도 일 때 취득된 거리의 값들을 수집한 후, 그 평균값을 임계치로 설정하는 방법이다. 이렇게 구해진 임계치를 이용 그 값보다 작은 지역을 도로로 인식하였으며，실험 결과 레이저 스캐너의 각도를 이용한 방법이 더욱 효과적으로 도로를 추출할 수 있음을 확인할 수 있었다.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1764-1769
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• 2010

본 연구에서는 산지하천 만곡수충부의 특성을 파악하기 위한 기초연구로서 홍수사상 발생 시 산지하천 만곡수충부 외측의 수위 상승효과를 확인하고자 하였다. 만곡수충부 모형을 제작하기 위하여 강원지역 지방하천에서 만곡수충부의 형태학적인 특성조사를 통한 대표 산지하천 만곡수충부 조건을 설정하였다. 수리모형실험을 위해 왜곡도 1.6의 고정상 만곡수충부 개수로 모형을 제작하여 유량에 따른 수충부의 수위상승을 조사하였다. 유량 $700m^3/s$에서 최대 3.150m의 편수위 상승이 발생하였고 유량에 따라 약간의 상이한 결과가 발생하였다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.3
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• pp.52-63
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• 2009

Recently in Korea, in the case of metropolis, the urban signalized intersections are controlled by traffic information center or ITS center. Cheon-an City also established traffic information center through the 1st.-$\sim$3rd. ITS public construction and has managed this center that includes bus information service, traffic information collection and providing service, parking information service, and traffic responsive control system. In the Cheon-an metropolitan traffic signal operation, traffic signal controllers were grouped by the each main traffic flow axes and performed with coordinated signal timing for the signalized arterials, and also cycle and split changed by realtime traffic demands. Cheon-an urban traffic responsive control system was evaluated by intersection delay and speed, then it was verified that the delay decreased and vehicle speed improved. However, the rural signal control system to connect adjacency town was evaluated to have lower status than urban area due to the unimproved TOD (Time of day) plan. Therefore actuated signal control was examined for substitutive control system in isolated signal intersection. The aim of this article is to compare actuated signal control with TOD mode in the rural intersection of Cheon-an and to fine superiority of these two control mode, with evaluation of vehicle delay by using HCM(2000) method and by micro-simulation CORSlM. The result of field test show that actuated signal control gave better performance in delay comparison than the existing TOD signal control. And simulation outcome verified that non-optimized TOD has higher delay than optimized TOD mode, non-optimal actuated mode, and optimal actuated signal control mode. Particularly, these three modes delays had not different values according to the paired sample t-test. This is because small traffic demands were loaded in each links. This suggested actuated signal control is expected to be more effective than TOD mode in some rural isolated intersections which frequently need to survey for traffic volume.

• International Area Studies Review
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• v.15 no.3
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• pp.471-491
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• 2011

This study is to analyze the determinants of inflow FDI with panel data of 12 provinces in western region of China for the period, 1990-2007, from the perspective of market-oriented FDI and production-efficiency-oriented FDI. The empirical findings are following. First, the empirical results prior to the start of western development program show that the GRDP, the intense of industrialization and university graduates per 10,000 residents have positive coefficient signs at the significant level, while wage level has a negative and significant value. Second the empirical results using the data after the launching of the western development program show that the GRDP, the intense of industrialization have positive relations with FDI, while openness in terms of the ratio of international trade to GRDP and the wage level have negative coefficients. Finally, this thesis finds that the empirical results for both periods are very similar, which suggest that the economic structure in western region has not changed significantly even though almost a decade passed since the western development program launched.