• 산업공학
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• 제22권4호
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• pp.368-375
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• 2009

This paper considers a two-stage supply system consisting of two make-to-stock facilities. The facility in the first stage produces a single type of component in anticipation of future demands from the market and the end item production while the facility in the second stage produces the end item in anticipation of future demands from the OEM customers. The facility in the first stage has the option of to accept or reject each incoming demand from the market. In this paper, we address the problem of how to control the exogenous component demand and how to manage the production of the end item and the component so as to maximize the system's profit subject to the system costs. In this paper, we present a heuristic policy that is the base-stock production policy combined with a linear switching curve for component demand control. Numerical study is implemented under different operating conditions of the system and it shows that the performance of the heuristic is very promising compared to that of the optimal policy for the Markov model.

• 산업경영시스템학회지
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• 제43권2호
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• pp.65-71
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• 2020

Worldwide plant market keeps maintaining steady growth rate and along with this trend, domestic plant market and its contractors also maintain such growing tendency. However, in spite of its external growth, win-win growth of domestic material industry that occupies the biggest share in plant industry cost portion is extremely marginal in reality. Domestic plant material suppliers are required to increase awareness of domestic material brand by securing quality and reliability of international standard through improvement of design quality superior to that of overseas material suppliers. Improvement of design quality of plant material becomes an essential element, not an option, for survival of domestic plant industry and its suppliers. Under this background, in this study, priority and importance by each evaluation index was analyzed by materializing plant design stage through survey of experts and defining evaluation index by each design stage and based on this analysis result, evaluation index of stage-gate based decision-making process that may improve design quality of plant material was suggested. It is considered that by utilizing evaluation index of stage-gate based decision-making process being suggested in this study, effective and efficient decision-making of project decision-makers would be enabled and it would be contributory to improve design quality of plant material.

• The Journal of Asian Finance, Economics and Business
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• 제6권2호
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• pp.15-24
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• 2019

This study analyzes the effect of the capital structure of Korean manufacturing firms on default risk based on Moody's KMV option pricing model where the probability of default is obtained by measuring the distance to default as a covariant in logit model developed by Merton (1974). Based on the panel data of manufacturing firms, this study achieves its primary objective, using a fixed effect regression model and examines the effect of a firm's capital structure on default risk amongst publicly listed firms on Korea exchange during 2005-2016. Empirical results obtained suggest that the rise in short-term debt to assets leads to increase the risk of default whereas the increase in long-term debt to assets leads to decrease the default risk. The benefits of short-term debt financing over a short-term period fade out in the presence of information asymmetry. However, long-term debt financing overcomes the information asymmetry and enjoys the paybacks of tax advantage associated with long-term debt. Additionally, size, tangibility and interest coverage ratio are also the important determinants of default risk. Findings support the trade-off theory of capital structure and recommend the optimal use of long-term debt in a firm's capital structure.

• KDI Journal of Economic Policy
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• 제40권4호
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• pp.1-22
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• 2018

We estimate three continuous-time stochastic volatility models following the approach by Aït-Sahalia and Kimmel (2007) to compare the Korean and US stock markets. To do this, the Heston, GARCH, and CEV models are applied to the KOSPI 200 and S&P 500 Index. For the latent volatility variable, we generate and use the integrated volatility proxy using the implied volatility of short-dated at-the-money option prices. We conduct MLE in order to estimate the parameters of the stochastic volatility models. To do this we need the transition probability density function (TPDF), but the true TPDF is not available for any of the models in this paper. Therefore, the TPDFs are approximated using the irreducible method introduced in Aït-Sahalia (2008). Among three stochastic volatility models, the Heston model and the CEV model are found to be best for the Korean and US stock markets, respectively. There exist relatively strong leverage effects in both countries. Despite the fact that the long-run mean level of the integrated volatility proxy (IV) was not statistically significant in either market, the speeds of the mean reversion parameters are statistically significant and meaningful in both markets. The IV is found to return to its long-run mean value more rapidly in Korea than in the US. All parameters related to the volatility function of the IV are statistically significant. Although the volatility of the IV is more elastic in the US stock market, the volatility itself is greater in Korea than in the US over the range of the observed IV.

• 아태비즈니스연구
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• 제12권3호
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• pp.343-359
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• 2021

Purpose - The purpose of this paper is to investigate the relationship between earnings management and the disclosure effect of share repurchase. In addition, we analyze whether the relationship between earnings management and share repurchase is affected by executive stock options. Design/methodology/approach - We calculate the discretionary accrual amount for the year immediately preceding the share repurchase and the cumulative excess return around the announcement of the share repurchase, and examine the relationship between the two by regression analysis. Findings - We confirmed a negative relationship between discretionary accrual in the year immediately preceding the share repurchase and the market response to the share repurchase disclosure. In particular, it was found that the negative relationship between discretionary accrual and stock price return on share repurchase announcement was found to decrease in companies to which executive stock options were granted. Research implications or Originality - When uncertainties exist in the motives for share repurchase, we find that earnings management and executive stock options can be useful tools for reducing the adverse selection risk inherent in share repurchase announcements.

• 한국건설관리학회논문집
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• 제4권4호
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• pp.96-105
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• 2003

타 산업, 특히 제조업 분야의 경우 급격한 기술 및 인터넷 환경의 발전으로 인해 시장이 세분화되고 다품종 소량생산의 체제로 변화하였다. 이러한 사회적 변화는 주택 시장에도 변화를 가져와 공급자 중심에서 수요자 중심의 시장으로 변화하고 있으며 주택에 대한 소비자의 요구사항도 날로 다양해지고 있다 한편 주택의 장수명화를 실현하고 지속가능 한 건축 및 환경 구현을 위해 오픈 하우징 시스템에 관한 연구가 활발히 진행되고 있는 시점에서, 오픈 하우징 개념을 도입한 맞춤형 아파트의 도입이 증가하고 있는 추세이다. 그러나 아직 도입 초기 단계이기 때문에 맞춤형 아파트의 운영에 있어 많은 문제점이 드러나고 있다. 따라서 본 연구에서는 맞춤형 아파트 사업이 효율적으로 이루어질 수 있도록 하기 위하여 최근 입주가 완료된 맞춤형 아파트의 실무자들과의 인터뷰 및 운영 사례를 조사하여 문제점을 분석하고 그에 따른 개선방안을 제시하였다.

• 전기학회논문지
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• 제62권10호
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• pp.1390-1396
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• 2013

The paper estimated the reasonable market price of lead-acid battery energy storage system (BESS) intended for demand management of electricity customers. As time-of-use (TOU) tariffs have extended to a larger number of customers and gaps in the peak and off-peak rates have gradually risen, deployment of BESS has been highly needed. However, immature engineering techniques, lack of field experiences and high initial investment cost have been barriers to opening up ESS markets. This paper assessed electricity cost that BESS operation could save for customers and, based on the possible cost savings, estimated reasonable prices at which BESSs could become a more prospective option for demand management of customers. Battery scheduling was optimized to maximize the electricity cost savings that BESS would possibly achieve under TOU tariffs conditions. Basic economic factors such as payback period and return on investment were calculated to determine reasonable market prices. Actual load data of 12 industrial customers were used for case studies.

• 조명전기설비학회논문지
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• 제23권4호
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• pp.8-15
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• 2009

본 논문은 전력시장 환경에서 수요관리 자원으로서 조광제어의 잠재량과 가치평가 방안을 제시한다. 일반적으로 수요자원의 경제성 평가를 위해 캘리포니아 테스트가 널리 사용되고 있다. 하지만 전력산업의 규제완화 및 구조개편으로 인한 새로운 시장 환경에서 캘리포니아 테스트를 적용하는데 한계가 있다. 특히 UC 테스트는 수직통합 전력회사에 적합하지만 발, 송, 배전이 분할된 전력회사에는 적합하지 않다. 따라서 본 논문에서는 전력시장 환경에서 전력판매회사 관점에서 수요관리 자원으로서 조광제어의 경제성을 평가하는 새로운 방법을 제시한다. 먼저 조광제어 자원의 잠재적 가치를 분석하고, 2006년 전력시장 데이터를 이용하여 판매회사 관점에서 조광제어의 경제성을 평가한다. 본 논문의 결과는 조광제어 자원이 전력판매회사 관점에서 비용-효과적인 수요관리 자원임을 보여 준다.

• 한국산학기술학회논문지
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• 제12권12호
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• pp.5671-5676
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• 2011

변동성지수는 옵션가격에 내재된 미래 기초자산의 변동성을 나타내는 지수이며, 투자자들이 예상하는 향후 주가 변동 가능성을 측정한 시장의 기댓값이다. 현재 한국거래소(KRX)에서 한국시장구조에 맞는 변동성지수를 개발하여 2009년 4월 13일부터 변동성지수(VKOSPI)를 발표하고 있다. 본 연구는 2002년부터 2008년까지 일별 데이터를 이용하여 기업규모, 시장기치 대 장부가치 비율 및 베타의 특징들로 그룹화된 포트폴리오의 미래 수익률에 대한 변동성지수의 예측력을 검증하였다. 그 결과 VKOSPI의 변화율은 미래수익률에 대해 강한 음(-)의 예측력을 갖고 있는 것으로 나타났으며, 이러한 결과는 Ang et al.[2]의 결과와 일치하고, 이는 VKOSPI가 수익률 결정요인이라 할 수 있다. 시장총변동성 추정치의 부호에 대해 Ang et al.은 시장 총변동성위험과 개별주식 수익률간의 음(-)의 관계로 설명하였다. 이는 시장 총변동성위험이 높아질 때, 시장변동성과 상관관계가 높은 주식은 시장위험에 대한 주식의 민감도, 즉 베타가 낮아져 개별주식 수익률이 하락한다는 것이다. 또한 포트폴리오를 그룹화하는데 베타가 포함되어진다면, 미래 수익률에 대한 VKOSPI의 예측력이 강하다는 것으로 나타났다.

• 멤브레인
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• 제23권1호
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• pp.24-44
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• 2013

MBR 기술은 지난 20여 년 동안 처리성능과 효율성 그리고 비용절감 측면에서 빠른 속도로 발전하고 있다. 또한 안정적인 하수처리와 하수재이용관점에서 핵심기술로 널리 인식되고 있다. 본고에서는 MBR 기술의 개발과 상업적 응용에 관한 발전과정을 재조명하고 세계 시장의 전망을 제시하고자 한다. 주요 적용기술에 대해 다음 5가지 측면에서 검토하여 제시하였는데 1) MBR 기술의 진화, 2) MRBs의 상업용 기술, 3) 대용량 MBR 플랜트 설치 사례, 4) MBR 시장의 성장, 5) 기술의 발전방향 순으로 제시하였다. 마지막으로 MBRs에 대한 경제적, 환경적, 그리고 기술적 측면에서 향후 발전방향을 1) 초기투자비, 2) 처리 수질, 3) 분리막 소재/모듈, 4) MBR 장비와 공정, 5) 운영비용, 향후 6) 혐기성 MBRs 공정과 같은 차세대 기술 분야로 나누어 제시하였다.