• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.457-461
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• 2006

비점원 농촌유역으로부터 강우시 영양물질(질소, 인)의 유출특성을 파악하기 위해 2002년부터 2005년까지 5개의 강우사상을 대상으로 $2{\sim}12$시간 간격으로 유량 및 수질을 측정하였다. 강우사상시 TN농도는 유량이 증가함에 따라 상승하여 최대농도를 보인 후, 유량감소에 따라 농도가 감소하는 경우와 초기농도보다 높은 농도로 유지되는 경우의 두 가지 경향을 보였다. TP농도는 유량의 증가에 따라 급격한 상승을 보였고, 최대 값 이후 농도가 낮아져 거의 초기농도에 도달하였다. 또한, 초기농도에 대한 최대농도값의 비는 TP가 TN보다 크게 나타났다. 농촌 소유역에서의 초기유출현상(first-flush)은 40%의 누적유출량을 나타낼 때 TP의 누적유출부하량은 $70{\sim}86%$를 기록하여, 도시유역(60%)과 광역논(50%)보다 크게 나타났는데, 이는 농촌 소유역이 경사가 크고 밭 등에서 강우로 인한 토양침식 등의 영향을 크게 받기 때문으로 사료된다. 4개의 강우사상에 대한 질소의 용존성 성분의 비(TN/TDN비)는 93.6%를 나타내 질소는 대부분 용존성 형태로 유출되는 것으로 나타났고, 인의 용존성 성분의 비(TP/TDP비)는 25.4%를 나타내 인의 대부분 입자성 형태로 유출되는 것으로 나타났다. 따라서, 비점원 농촌유역으로부터 TN부하를 저감시키기 위해서는 용존성 성분을 제공하는 비료의 시용량을 줄여야 하며, TP부하를 저감시키기 위해서는 강우시 입자성 인의 유출을 제어해야 한다. 이를 위해서는 비가 많이 오는 여름철에 나지(裸地)나 밭에 식생이나 멀칭(mulching) 등으로 토양침식을 방지하는 대책이나 하천변에 완충역(riparian buffer zone)을 설치하는 대책이 필요하다. 저수지 관리를 효과적으로 수행하기 위해서는 저수지 내부의 탁도 거동을 정확히 예측할 수 있어야 한다. 따라서 추후 동수역학 및 열역학에 기초한 3차원 수치모형 연구와 성층흐름에 정밀한 밀도류 실험연구 및 이에 대한 적용이 필요할 것으로 판단된다.함으로써 정보의 질적보장과 정보전환의 표준화방안을 제시하는 정보분석시스템이다.이용, 수자원의 지속적 확보기술의 특성에 따른 4개의 평가기준과 26개의 평가속성으로 이루어진 2단계 기술가치평가 모형을 구축하였으며 2개의 개별기술에 대한 시범적용을 실행하였다.하는 것으로 추정되었다.면으로의 월류량을 산정하고 유입된 지표유량에 대해서 배수시스템에서의 흐름해석을 수행하였다. 그리고, 침수해석을 위해서는 2차원 침수해석을 위한 DEM기반 침수해석모형을 개발하였고, 건물의 영향을 고려할 수 있도록 구성하였다. 본 연구결과 지표류 유출 해석의 물리적 특성을 잘 반영하며, 도시지역의 복잡한 배수시스템 해석모형과 지표범람 모형을 통합한 모형 개발로 인해 더욱 정교한 도시지역에서의 홍수 범람 해석을 실시할 수 있을 것으로 판단된다. 본 모형의 개발로 침수상황의 시간별 진행과정을 분석함으로써 도시홍수에 대한 침수위험 지점 파악 및 주민대피지도 구축 등에 활용될 수 있을 것으로 판단된다. 있을 것으로 판단되었다.4일간의 기상변화가 자발성 기흉 발생에 영향을 미친다고 추론할 수 있었다. 향후 본 연구에서 추론된 기상변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기 위한 연구가 필요할 것이다.게 이루어질 수 있을 것으로 기대된다.는 초과수익률이 상승하지만, 이후로는 감소하므로, 반전거래전략을 활용하는 경우 주식투자기간은 24개월이하의 중단기가 적합함을 발견하였다. 이상의 행태적 측면과 투자성과측면의 실증결과를 통하여 한국주식시장에

• Environmental and Resource Economics Review
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• v.20 no.3
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• pp.531-565
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• 2011

All previous studies analyzing multivariate time series data of EUA (European Union Allowance) price commonly used endogenous variables within the four variables and included the period from April to June of 2006 in the analysis, when the price distortion occurred. This study uses graph theory and structural vector error correction model (SVECM) to analyze the daily time series data of the EUA (European Union Allowance) price. As endogenous variables, five variables are considered for the analysis, including prices of crude oil, natural gas, electricity and coal in addition to carbon price. Data period is Phase 2 period (April 21, 2008 to March 31, 2010) to avoid the EUA price distortion of Phase 1 period (2005~2007). Further, the monthly data including the economic variables as endogenous variables are analyzed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.4
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• pp.877-886
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• 2009

Since 1982, the auditee have selected the auditor under market mechanism. Under the system on which the auditor have been chosen by client, there have been chances for opinion shopping, etc. To prevent those, some audit regulations have been introduced. Prior studies have documented the positive effect of these audit regulations. Those studies, however, had some limitations which they dealt with just short event period for empirical tests. This study examines the effect of Auditor Turnover Ratio on the Quality of Earnings using a sample of firms that were listed on Korea Exchange(KRX) from 1995 to 2004. The firms that change auditor frequently are expected to have low disclosure quality. The CEO with the incentives to manage or manipulate earnings could accomplish this purpose by replacing existing auditor with more friendly auditor, which could result in eventually lowering earning's quality of the firm. The result of empirical test shows that the accrual quality of firms which have high auditor turnover ratio are significantly lower than those of firms which have low ratio. This result is consistent with our hypothesis that the more frequently a firm changes auditor, the lower the quality of earning is. This evidence might give the implication to policy-making supervisor.

• The Korean Journal of Financial Management
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• v.23 no.1
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• pp.1-47
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• 2006

This study investigated the effect of tender-offer on the value of the firms in Korea. For this purpose, the study applied an event study methodology to 55 cases(bidding firm : 26, target firm : 39) of tender-offer and 164 cases(bidding firm : 144, target firm : 20) of merger announcements made between January 1st, 1994 and September 30th 2004. We found the following results. For tender-offer announcements, there was a significant increase in target firm's value while there was no significant change in bidding firm's value. In contrast, for merger announcements, there was a significant increase in bidding firm's value while there was no significant change in target firm's value. In addition, the synergy effect of tender-offer was higher than that of merger. The results support the Berkovitch and Khanna(1991)'s prediction that bidding firms choose tender-offer rather than merger in the presence of higher synergy profit from M&A.

• Korean Journal of Poultry Science
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• v.32 no.3
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• pp.179-186
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• 2005

This study was conducted to establish a comprehensive guideline for grading system of poultry meat cuts. Slaughter and further processed houses were divided into large(>70,000 heads/day), middle($50,000\~25,000$ heads/day), and small scale(<25,000 heads/day), and the production managers were asked by the Questionnaire. Most poultry meat cuts produced by larger- and middle-slaughter house were consumed by dealers, franchisee and department store in increasing order, whereas further processed poultry meat cuts(small scale) provided meals for the students in the high amount. The packaging step was best f3r the determination of grading in the large slaughter house. This survey indicated that two or more grades were proper to determine the grading in the middle slaughter house, however only two grades were proper for the others. Freshness, bruise, wound, trimming and the inclusion of foreign materials affected to the grading. Poultry meat cuts were accepted for the grading in large-slaughter house, but whole poultry carcass was accepted for the grading in the others. Most managers agreed with that the grading system was only applied for the amounts requested. They also suggested that the grading system of poultry meat cuts were necessary in near future, even though it was not urgent to apply.

• Journal of the Economic Geographical Society of Korea
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• v.8 no.2
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• pp.247-266
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• 2005

The purpose of this paper is to analyse the effects of a firm's financial and non-financial factors on the relationship formation with its main bank in the industry of parts and material in Pusan-Kyungnam region. The results, out of accordance with the relation-banking or regional financial market perspective, do not support the hypothesis that regional financial institutions would be useful for decreasing the financial difficulties of the small and medium firms in the region. The analyses about the effects of non-financial factors on the formation of main bank relations show that while Kookmin Bank and Industrial Bank play important roles as main banks of small businesses other national banks put emphasis on the transaction lending. And the analyses about the effects of financial factors show that firms having main bank relations with non-bank financial institutions and Kookmin bank are more profitable and stable than firms having main bank relations with other banks including local banks. On the whole it seems that local banks are not making a commitment to the regional economy and their operational grounds are not strong enough.

• Journal of Digital Convergence
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• v.11 no.11
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• pp.191-196
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• 2013

The proportion of small and medium sized enterprises based on the number of corporations in China is 99%, the number of employees is 80%, and the proportion of GDP is 60%. These facts show that small and medium sized enterprises have an very significant effect on the economic growth of China. However, most of the researches conducted so far have studied large corporations, thus, there are relatively insufficient researches on the determinant of the capital structure of small and medium sized enterprises. Therefore, the purpose of this paper is to confirm the factors that determine the capital structure of small and medium sized enterprises in China. To achieve this purpose, we performed multiple regression method to 45 small and medium sized manufacturing enterprises listed on the Shenzhen Stock Exchange of China. Results of this study are as follows. First, the growth appeared to have a significant positive effect to the debt ratio in 1% significance level. Second, the profitability appeared to have a significant negative effect to debt ratio in 1% significance level. Third, the firm size appeared to have no effect on the debt ratio. Fourth, the secured value and tax shield effect by non-debt appeared to have a weak positive effect on the debt ratio, however these variables showed statistical insignificant.

• Spatial Information Research
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• v.22 no.3
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• pp.47-58
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• 2014

The credible measurement, reporting and verification (MRV) is among the most critical elements in UN-REDD (United Nations programme on Reducing Emissions from Deforestation and forest Degradation in Developing Countries). This study is intended to explore MRV potential in terms of UN-REDD opportunity cost estimation using satellite image for Mt. Geum-gang of North Korea. A visual interpretation were conducted to evaluate MRV conditions by sub-dividing or decomposing the images with different pixel size into a three types of hierarchical tree structure that helps dealing with spatial variability within each subarea. The permanent record of standard satellite remote sensing system demonstrated its capability of presenting area-wide visual evidences of MRV conditions in Mt. Geum-gang (such as the identification of forested area, degradation trends for forest space, three types of hierarchical land-cover and land use tree structure, carbon density in the landscape). Satellite data could be accepted as legally binding proof when it comes to REDD opportunity cost estimation since several cases exist where remote sensing has been used as legal evidence in ICJ (International Court of Justice) and UN resolution. It doesn't seem very difficult to comply with MRV requirements for UN-REDD opportunity cost calculation due to the probative value of satellite data. It is anticipated that this research output could be used as a valuable reference for Korea-based enterprises exploring REDD project sites and the carbon traders to ensure MRV potentials using satellite image in UN-REDD Opportunity Cost estimation.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.24 no.5
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• pp.781-793
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• 2014

A Public Key Infrastructure (PKI) is security standards to manage and use public key cryptosystem. A PKI is used to provide digital signature, authentication, public key encryption functionality on insecure channel, such as E-banking and E-commerce on Internet. A soft-token private key in PKI is leaked easily because it is stored in a file at standardized location. Also it is vulnerable to a brute-force password attack as is protected by password-based encryption. In this paper, we proposed a new method that detects private key compromise and is probabilistically secure against a brute-force password attack though soft-token private key is leaked. The main idea of the proposed method is to use a genuine signature key pair and (n-1) fake signature key pairs to make an attacker difficult to generate a valid signature with probability 1/n even if the attacker found the correct password. The proposed method provides detection and notification functionality when an attacker make an attempt at authentication, and enhances the security of soft-token private key without the additional cost of construction of infrastructure thereby extending the function of the existing PKI and SSL/TLS.

• Journal of Climate Change Research
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• v.3 no.2
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• pp.129-142
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• 2012

This study was carried out to evaluate carbon footprint during unhulled rice production and to compare mitigation technologies of methane, main carbon source during rice production, Carbon footprint of unhulled rice was a sum of $CO_2$ emission of agri-materials manufacture, rice cultivation and waste treatment. It was emitted 1.40 kg $CO_2$ during unhulled rice production, its distribution was 71.1% by $CH_4$ emission of rice cultivation, 11.8% of $N_2O$ emission by nitrogen application and 7.6% of complex fertilizer manufacture. $CH_4$ emission could be mitigated by some technologies; cultivation of the early maturing rice variety emitted lower by 44.4% than the mid maturing variety, intermittent drainage of submerged water by 43.8% than the continuous flooding condition, direct seeding by 32.0% than transplanting cultivation, no-ploughing by 20.9% than ploughing cultivation. It means that LCA on Global Warming Potential and the statistical data on innovated technical practice are key tools to systemize Measurable-Reportable-Verifiable (MRV) system for carbon footprint and carbon emission trade in the farm base.