• Title/Summary/Keyword: spillover

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Traffic Analysis Model for Exit Ramp Congestion at Urban Freeway (고속도로 진출램프 대기행렬 발생 현상 분석모형 개발)

  • Jeon, Jae-Hyeon;Kim, Young-Chan
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.9 no.3
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    • pp.30-40
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    • 2010
  • The freeway congestion is largely generated by a mainline spillover of the exit ramp queue. So it is necessary to study for modeling of the phenomenon and applying the model. In this study, the authors evaluated applicability of the Supply-Demand model, which can express traffic flow for the freeway by applying flexibly supply and demand curves for capacity of the freeway. First the authors proposed methods processing input data required in the Supply-Demand model, such as sending & receiving functions and time-varying capacity constraints for the freeway mainline. After modeling the Supply-Demand application model, the authors applied the model to the site including congested Hongeun exit ramp in Seoul Ring-road, and improved the model by adjusting application techniques and calibrating parameters. The result of the analysis showed that the Supply-Demand model yielded a queuing pattern and queue location similar to them observed in the field data, and applicability of the Supply-Demand model was varified.

On the Estimation of Regional Job-matching Functions of Korea (우리나라의 지역별 일자리결합함수의 추정)

  • Yang, Jun-Seok;Kim, Ho-Yeon
    • Journal of the Economic Geographical Society of Korea
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    • v.12 no.3
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    • pp.248-259
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    • 2009
  • This paper analyzes the interactions among regional labor markets in Korea. Specifically, we focus on the job market externality between neighboring regions. To estimate the job matching functions, we construct panel data on unemployment, vacancies and hires for the period of January 2004 through December 2007 for 15 cities and provinces in Korea. We employ various spatial econometric techniques to avoid the problem of spatial autocorrelation which frequently arises when dealing with regional data. Main findings are as follows. First, estimation results are consistent with conventional job matching theory. That is, as the number of job searchers and vacancies increase, the number of hires also rises. And it is relatively easier for firms to hire workers than for job seekers to find jobs. Second, it is found that, other things equal, the possibility of job matching is higher in large metropolitan areas than rural areas. Finally, the findings show that the number of job searchers in neighboring areas is negatively correlated with the number of hires in the area. Likewise, the number of vacancies in neighboring areas is positively correlated with number of hires in the area. These provide clear evidence on the existence of regional spillover effects.

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DETERMINANTS OF US CVB'S WEBSITE SERVICE QUALITY (미국 컨벤션뷰로의 웹사이트 서비스 품질결정요인)

  • Kim, Min-Sook;Bang, Ho-Yeol
    • International Commerce and Information Review
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    • v.10 no.4
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    • pp.125-151
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    • 2008
  • Website service quality is widely accepted as one of the key determinants of online business success. Several studies identified key factors that determine the website service quality factors appropriate for online business environments. A convention and visitors bureau (CVB) website is a service portal that delivers information online about a destination so users can develop an overall image of the location. CVBs struggle to deliver positive destination images because the competition among destinations to host conventions is intense. In spite of the important role of CVBs and the beneficial spillover effect of CVBs, there are few studies available reporting on the unique service qualities of a CVB website. The primary purpose of this study was to examine the determining factors that are appropriate for CVB websites from the meeting planners' perspective. The research questions arc: What are the determining factors of service quality of a CVB website? Do the determining factors of CVB website service quality positively influence meeting planners' satisfaction? The new conceptual framework was developed from a variety of destination marketing and Internet marketing concepts: e-servicescape management, web community network, Internet service encounter management, and online system quality. Empirical results indicate that three of the four factors, that is, e-servicescape, web community network, and online system quality are important determinants in evaluating CVB website service quality. The findings also show that three determinants have significant and positive influence on meeting planners' satisfaction. The findings from this study will provide meaningful advice for CVB website quality management. To enhance the CVB website service quality and satisfaction level of meeting planners, these three determinants' should be considered of the utmost strategic importance and priority.

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Analysis of Future Growth in Korea Movie Industry (한국영화산업의 발전방향 분석)

  • Choi, Eun-Young
    • The Journal of the Korea Contents Association
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    • v.8 no.11
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    • pp.134-143
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    • 2008
  • The significance of the image content industry, as a flagship industry of the cultural content industry, is emerging globally as a high value-added trend. Since the movie industry has diverse related industries along with a positive spillover effect from cultural and economic perspectives, it ultimately strengthens national brands as well as national competitiveness. As a national strategy cultural content industry, the movie industry in each country around the world utilizes its own diverse self-protective systems. The Korean movie industry has emerged as a 10 million-strong movie-goer market; however, in reality, it is vulnerable to high film production costs and utility. The current domestic media market demands a new paradigm through the media industry as a whole; nonetheless, it is inherently limited to past film production and distribution channels. In this study, I seek to evaluate the status quo and propose a new direction for the Korea movie industry.

Is the technology in renewable energy converging among countries? : Using the patent data of OECD (재생에너지 분야 국가 간 기술 확산 및 수렴 : OECD 특허 데이터를 이용한 분석)

  • Oh, Keunyeob;Yoo, Jinman
    • Environmental and Resource Economics Review
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    • v.23 no.1
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    • pp.67-89
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    • 2014
  • This paper uses patent data of OECD countries in order to investigate if there is converging tendency in renewable energy area. We used the concepts of sigma convergence and beta convergence to measure the convergence. GINI coefficient, HH index are also borrowed from other area of economics. The results show that technology level does not seem to have been converging in this area. Even though the number of patent in relatively less advanced countries has been increased a lot, we could find no evidence that there is the tendency that the gap among the countries have been narrowed. This is quite different from the results of IT industry or other industry since we could find the converging tendency in the data of those industries. Instead, it seems that there is the convergence club among most advance countries in renewable energy area.

Quantification of myocardial blood low using dynamic N-13 ammonia PET and actor analysis (N-13 암모니아 PET 동적영상과 요소분석을 이용한 심근 혈류량 정량화 방법 개발)

  • Kim, J.Y.;Choi, Y.;Im, K.C.;Choe, Y.S.;Lee, K.H.;Kim, S.E.;Kim, Y.J.;Kim, B.T.
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.11
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    • pp.575-578
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    • 1997
  • Myocardial blood low (MBF) in human can be noninvasively quantified using dynamic N-13 ammonia PET and two-compartment tracer kinetic model. In this study, factor analysis was used to extract the "pure" blood-pool time-activity curves (TACs) and to generate actor images. ive human N-13 ammonia PET dynamic studies were obtained. Three actors and their corresponding actor images were extracted rom each study. The accuracy of MBF estimated by the actor analysis (FA/FA MBF) was examined by comparing to the values estimated using the conventional ROI method (ROI/ROI MBF). MBF obtained by the actor analysis linearly correlated with MBF obtained by the ROI method (slope=0.98, r=0.91). Input unctions obtained by the two methods agreed well. In conclusion, MBF can be measured accurately and noninvasively with dynamic N-13 ammonia PET imaging and actor analysis. This method is simple and acurate and can measure MBF without blood sampling, ROI drawing nor spillover correction.

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An Analysis of the Growth, Education and Academic Research Trends of iSchools (iSchool 대학의 발전, 교육 및 연구 동향 분석)

  • Chang, Yunkeum
    • Journal of the Korean Society for Library and Information Science
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    • v.48 no.1
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    • pp.369-386
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    • 2014
  • The iSchool movement has been rapidly spread out since the foundation of iSchool Caucus (iCaucus) in 2005, which currently 52 schools have joined across 16 countries. This research aims to investigate the advances in this movement and its impact on education and research in the field of library and information science (LIS) in order to explore future trends in LIS education and research. To do so, this study classifies 21 ALA-accredited iSchools into three groups suggested by King (2006) and comparatively analyzes each group in terms of its temporal advances and curriculum characteristics. Moreover, as the new movement of Massive Open Online Courses (MOOCs) has been rapidly progressing with the initiative of North American schools since 2012, this study also intends to diagnose the possibility of its spillover effect in LIS education by examining application cases.

Estimating the CoVaR for Korean Banking Industry (한국 은행산업의 CoVaR 추정)

  • Choi, Pilsun;Min, Insik
    • KDI Journal of Economic Policy
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    • v.32 no.3
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    • pp.71-99
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    • 2010
  • The concept of CoVaR introduced by Adrian and Brunnermeier (2009) is a useful tool to measure the risk spillover effect. It can capture the risk contribution of each institution to overall systemic risk. While Adrian and Brunnermeier rely on the quantile regression method in the estimation of CoVaR, we propose a new estimation method using parametric distribution functions such as bivariate normal and $S_U$-normal distribution functions. Based on our estimates of CoVaR for Korean banking industry, we investigate the practical usefulness of CoVaR for a systemic risk measure, and compare the estimation performance of each model. Empirical results show that bank makes a positive contribution to system risk. We also find that quantile regression and normal distribution models tend to considerably underestimate the CoVaR (in absolute value) compared to $S_U$-normal distribution model, and this underestimation becomes serious when the crisis in a financial system is assumed.

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The Impact of Innovative Collaboration on the Performance of Small and Medium Enterprises (혁신을 위한 외부협력이 중소기업성과에 미치는 영향에 대한 다각적 분석)

  • Hwang, Jung-Tae;Han, Jae-Hoon;Kang, Hee-Jong
    • Journal of Korea Technology Innovation Society
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    • v.13 no.2
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    • pp.332-364
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    • 2010
  • External linkages affect the performance of small and medium enterprises in diverse ways. This study delves into the impact of inter-organizational collaboration by looking at different facets of performance, such as innovation, sales growth, profit growth, and firm survival. In addition, it explores the influence of informal knowledge spillover from collaborative partners as well as from formal collaborations. The impact is carefully investigated by dividing firm samples into three different sectoral innovation categories: supplier-dominant, production-intensive, and science-based sector suggested by Pavitt (1984). The result highlights the different influence pattern of collaborative relations by partner types according to sectoral categories. The positive results of collaborating with universities and public institutions are identified, and the sales growth by customer linkage is witnessed. The impact is apparent in science-based sectors. The result implies that the risk associated with collaborating with competitors may be moderated by linking performance enhancing collaborative linkages with universities and government institutes.

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Reaction Scheme on the Direct Synthesis of Methylchlorosilanes (Methylchlorosilanes의 직접 생산 반응에서 반응기구)

  • Kim, Jong Pal;Lee, Kwang Hyun
    • Korean Chemical Engineering Research
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    • v.56 no.2
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    • pp.291-296
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    • 2018
  • Direct synthesis of methylchlorosilanes was developed by Rochow with addition of copper on the silicon surface as a catalyst and many research were followed. Most of research were focused on the increase of reaction activity through addition of promoters and concentrated on the increase of selectivity of DMDC. However, there are very few studies about the reaction mechanism. Although formation of DMDC was explained in literature, formation of other silanes were not mentioned at all. This reseach focused on the explanation about formation of all silanes obtained during direct reaction and TPD. Reaction paths were proposed by means of dissociative adsorption of methyl chloride and spillover of surface Cl and H. Surface silicon sites were considered as $=SlCl_2$ and $=Sl(CH_3)Cl$. The synthesis of all methylchlorosilanes were explained by the adsorption of methyl group on the silicon sites and by the surface diffusion of nearby Cl and H. The proposed reaction mechanism explains the formation of all silanes during the reaction and also during the TPD process.