• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2009년도 학술발표회 초록집
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• pp.89-93
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• 2009

홍수기에 집중되는 하천유출량을 갈수기에 적절히 활용하기 위한 대표적인 시설이 댐이다. 제한된 용수공급량을 적절히 분배해 용수수요량을 만족시키면서 미래 갈수기시 용수공급을 위한 댐 저류량을 조절하는 것이 댐 운영의 중요한 목적 중 하나이다. 본 연구에서는 댐 저류량에 따라 댐 계획방류량을 일정비율 줄여주는 Hedging Rule을 5단계로 적용하여 댐의 상시만수위 저류량에 대한 실제 저류량의 편차 절대치 합, 수요에 대한 용수공급 부족량의 합, 그리고 하천유지유량에 대한 하천유량 부족량의 합을 목적함수로 하여 혼합정수 선형계획법(MILP, Mixed Integer Linear Programming)으로 식을 구성하였다. 한강수계의 다목적댐인 충주, 횡성, 소양강 댐과 용수전용댐인 광동 댐, 그리고 발전용 댐이지만 비교적 큰 저류용량을 가진 화천 댐을 댐 연계 운영 대상으로 하여 수자원장기종합계획의 2003년 유출량 및 수요량 자료와 댐운영실무편람의 댐 계획방류량 자료를 10일 단위로 입력하여 GAMS/CPLEX를 이용해 최적화하였다. 그 결과 생공용수 수요량 99.99%, 농업용수 수요량 99.91%, 그리고 하천유지용수 수요량 99.24%를 충족시키면서, 댐 저류율이 66.54%에서 86.39%로 증가하였다.

• 영어어문교육
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• 제17권4호
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• pp.177-191
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• 2011

This paper examines nursing professionals' English abstract to learn their preferences towards tense and voice choices. A total of 24 abstracts, completed reviews to be published by the editorial board members of the Korea Industrial Nursing Association, were analyzed for the study. Each sentence in the four parts of the abstract (Purpose, Methods, Results, and Conclusion) was examined and classified into active/passive voices, and present/past/present perfect tenses. Verbs were then further identified to see which ones were commonly preferred to state the objectives of the study, methods, and to draw conclusions. Hedging expressions in Conclusion were also examined. The results of the present study revealed that Purpose was mostly (79%) stated in the past tense with slight use (17%) of the present tense in the form of 58% active and 42% passive voice whereas Methods were dominantly (96%) illustrated in the past tense with preference of mixed active and passive voice. The Results were also preferably (92%) stated in past tense and Conclusion in both present and past tense. Verbs used by these nursing professionals seemed diverse; however, hedging appeared to be narrowly limited to a few expressions including suggest and should. More diverse English hedging expressions need to be taught at least college level writing so that the EFL learners and writers can have a better understanding of presenting statements in an appropriate level of caution, confidence, or uncertainty.

• 대한수학회보
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• 제56권5호
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• pp.1129-1141
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• 2019

We propose a stochastic delay financial model which describes influences driven by historical events. The underlying is modeled by stochastic delay differential equation (SDDE), and the delay effect is modeled by a stopping time in coefficient functions. While this model makes good economical sense, it is difficult to mathematically deal with this. Therefore, we circumvent this model with similar delay effects but mathematically more tractable, which is by the backward time integration. We derive the option pricing equation and provide the option price and the perfect hedging portfolio.

• Journal of Applied and Pure Mathematics
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• 제4권5_6호
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• pp.287-297
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• 2022

In this paper, we consider a risk-minimization hedging problem for a special European contingent claims. The existence and uniqueness of strategy are given constructively. Firstly, a non-standard European contingent is demonstrated as stochastic payment streams. Then the existence of the risk minimization strategy and also the uniqueness are proved under two kinds market information by using Galtchouk-Kunita-Watanabe decomposition and constructing a 0-achieving strategy risk-minimizing strategies in full information. And further, we have proven risk-minimizing strategies exists and is unique under restrict information by constructing a weakly mean-selffinancing strategy.

• 한국콘텐츠학회논문지
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• 제14권11호
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• pp.905-914
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• 2014

본 연구는 2010년 1월 5일부터 2013년 10월 31일까지의 일별자료를 이용하여 KOSPI200 현물에 대하여 KODEX200 ETF 또는 KOSPI200 선물로 헤지포지션을 구성한 경우와 KODEX200 ETF와 KOSPI200 선물로 헤지포지션을 구성했을 때 헤지성과를 단순헤지모형, 최소분산모형, 벡터오차수정모형을 이용하여 상호 비교분석하였다. 본 연구의 결과를 요약하면 다음과 같다. 첫째, KOSPI200과 KODEX200 ETF, KOSPI200 선물 그리고 KODEX200 ETF와 KOSPI200 선물 간에는 공적분 관계가 존재하여 이들 간에는 장기적으로 균형관계에 있는 것으로 나타났다. 둘째, 헤지성과는 모형들 간에 차이가 없는 것으로 나타났다. 마지막으로 헤지성과는 KOSPI200 현물과 KOSPI200 선물로 헤지포지션을 구성하는 것 보다는 KOSPI200 현물과 KODEX200 ETF 또는 KODEX200 ETF와 KOSPI200 선물로 헤지포지션을 구성하는 것이 높은 것으로 나타났다. 이러한 결과는 포트폴리오 관리자가 KOSPI200 현물에 대해 위험관리를 함에 있어서 헤지수단으로서 KOSPI200 선물 대신에 KODEX200 ETF를 이용하거나, KOSPI200 현물로 포트폴리오를 구성하는 대신에 KODEX200 ETF를 이용하고 KOSPI200 선물로 헤지포지션을 취하는 것이 위험관리에 있어서 더욱 효과적임을 의미한다.

• 한국시스템다이내믹스연구
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• 제15권4호
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• pp.5-28
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• 2014

국제통상을 하는 기업은 위험 선호도에 따라 금융시장을 통해 외화자산 혹은 외화부채의 헷징(hedging)을 목적으로 파생금융상품을 쉽게 구매할 수 있다. 파생금융상품 시장은 투자와 헷지의 필요에 따라 급속도로 성장해왔다. 기업은 금융 파생금융상품을 통해 환위험 관리를 하면서 위험을 헷징한다. 기초자산을 헷징할 때는 환노출 완화전략으로 헷징이 효과적일 수 있다. 하지만 파생상품을 통한 이익에 대한 욕심과 예상치 못한 환율 변동이 발생할 때 기업에 상당한 위험을 초래할 수도 있다. 본 논문은 환위험을 다루는 파생상품에 내재된 구조적인 위험을 시스템다이내믹스 관점에서 분석하고 있다. 대표적인 파생금융상품인 KIKO는 구조적인 위험 요인 때문에 금융위기에 크나 큰 손실을 끼쳤다. 본 논문에서는 KIKO의 구조적 위험 요인을 모델링하고 실제 사례를 통해 검증하여 파생금융상품의 시스템 구조를 파악하고 내재되어 있는 구조적 위험을 밝혔다.

• Journal of Korea Trade
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• 제26권3호
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• pp.45-62
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• 2022

Purpose - Using unexpected changes in geopolitical tensions on the Korean peninsula as a quasi-natural experimental setting, we examine whether and how geopolitical risks travel across borders through firm-level imports and exports linkages. We also test whether the effects are driven by either imports or exports and assess whether firms can effectively hedge themselves against geopolitical risks. Design/methodology - We focus on a series of unanticipated geopolitical events taken place in Korea in 2018. Making use of the shocks to geopolitical climate, we identify five milestone events toward peace talks. We employ the event studies methodology. We examine heterogenous firm-level stock price reactions around key event dates depending on firms' exposure to geopolitical risks. As a measure of firms' exposure to geopolitical risks in Korea, we utilize a text-based measure of firm-level trade links. When a firm announces and discusses its purchase of inputs from Korea or sales of outputs to Korea in their annual disclosure filings, we define a firm to have a trade relationship with Korea and have exposure to Korean geopolitical risks. Similarly, we use a measure of a firm's hedging policies based on a firm's textual mention of the use of foreign exchange derivatives in their annual disclosure. Findings - We find that U.S. firms that have direct trade links to Korea gained significantly more value when the intensity of geopolitical risks drops compared to firms without such trade links to Korea. The effects are pronounced for firms purchasing inputs from or selling outputs to Korea. We find that the effectiveness of foreign exchange hedging against geopolitical risks is limited. Originality/value - We document the international transmission of geopolitical uncertainty through trade linkages. Export links as well as import links serve as important nexus of transmission of geopolitical risks across borders. Hedging strategies involving foreign-exchanges derivatives do not seem to insulate firms again geopolitical risks. With the recent movements of localization and reshuffling of the global value chain, our results suggest a significant impact of geopolitical risks in Korea on the construction of the global value chain.

• 한국디지털건축인테리어학회논문집
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• 제12권1호
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• pp.35-43
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• 2012

This study aimed to seek a method capable of hedging a rising risk of housing rent price by introducing derivatives with the target of Korean housing rent markets. The research model used in this thesis progressed a research by applying a futures contract method with the target of the rent price of major apartments in Gangnam and Gangbuk Regions of Seoul. As an analysis result, the rent price of all complexes has risen during its analysis period, so it could be confirmed that the CRB future index was also risen according to this. Finally, it was confirmed that the rising risk of the rent price can be hedged through a purchase position of futures. But, as the difference between rent price variation and CRB future index variation occurs, it appeared that 100% of hedge is difficult. However, it is judged that if considering that a method capable of hedging the rising risk of the existing rent price was nonexistent, the hedge trading effect utilizing the CRB future index on the rent price will be meaningful.

• 무역상무연구
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• 제55권
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• pp.185-208
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• 2012

Before and after the Capital Market Integration Act in 2007 is implemented in South Korea, many of small-and mid sized exporting companies in South Korea has been bankrupted or filed for lawsuit claiming mis-selling(KIKO) by the banks. The basic economic structure of KIKO in Korea are part of a business model based on the use or misuse of exotic derivatives whose results are anything but imaginary. 571 mid sized exporting companies have been damaged about $28 billion. KIKO is a currency option product that sells foreign currencies at higher foreign exchange rate when the rate moves within a certain range, but sells foreign currencies at two or three times lower rate than the market price when the rate exceeds the designated upper limit. KIKO, Therefore, is hard to know whether the non financial firms intended to hedge against further strengthening of their currency or merely to speculate. It is also hard to know how thoroughly they understood the risk-return profile of these transactions. It is similarly hard to ascertain whether the derivatives dealers offering these transactions were meeting the demands of their clients or taking advantage of them. These exotic derivatives were inappropriate for either hedging or speculating, and no knowledgeable investor would be likely to enter into these contracts intentionally.

• KIEE International Transactions on Power Engineering
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• 제3A권1호
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• pp.53-60
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• 2003

At present the electric power industry in Korea is going through a major restructuring process. The restructuring is motivated by a desire to reduce electricity supply costs, to attract new in-vestment in modern generation, transmission and distribution facilities, and to stimulate innovation in the wholesale production and the retail supply of electricity. The experience to date shows that restructuring of electric power industry in the US, however, is marred with a number of problematic market performances including unreasonably high prices at wholesale. This paper investigates the important role of Power Exchange for stabilizing electric power industry in transition by offering various financial products. These financial products are used for risk hedging by the market participants. The paper focuses on the risk hedging by an individual supplier and derives an explicit decision rule that incorporates the attitude towards the risks. In addition to providing the financial products for risk hedging by market participants, the Power Exchange plays another very important role of financial safeguard system. Because of its unique characteristics, the Power Exchange is well suited for financial surveillance where it performs the early detection of unsound financial (and to a large extent operational) practices on the part of any system users and protect the system integrity and the market participants from the consequences of a default in the clearing structure.