• 제어로봇시스템학회논문지
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• 제12권12호
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• pp.1169-1172
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• 2006

The prices of chemical products are fluctuated by several factors. The chemical companies can't predict and be ready to all of these changes, so they are exposed to the risk of a profit fluctuation. But they can reduce this risk by making a well-diversified product portfolio. This problem can be thought as the optimization of the product portfolio. We assume that the profits come from the 'spread' between a naphtha and a chemical product. We calculate a mean and a variation of each spread and develop an automatic module to calculate the optimal portion of each product. The theory is based on the Markowitz portfolio management. It maximizes the expected return while minimizing the volatility. At last we draw an investment selection curve to compare each alternative and to demonstrate the superiority. And we suggest that an investment selection curve can be a decision-making tool.

• 산업경영시스템학회지
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• 제32권4호
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• pp.63-71
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• 2009

The traditional portfolio optimization problem is to find an investment plan for securities with reasonable trade-off between the rate of return and the risk. The seminal work in this field is the mean-variance model by Markowitz, which is a quadratic programming problem. Since it is now computationally practical to solve the model, a number of alternative models to overcome this complexity have been proposed. In this paper, among the alternatives, we focus on the Mean Absolute Deviation (MAD) model. More specifically, we developed an algorithm to obtain an optimal portfolio from the MAD model. We showed mathematically that the algorithm can solve the problem to optimality. We tested it using the real data from the Korean Stock Market. The results coincide with our expectation that the method can solve a variety of problems in a reasonable computational time.

• Asia pacific journal of information systems
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• 제27권4호
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• pp.233-244
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• 2017

IT portfolio, meaning the ratio of investment with four different purposes of IT, is widely used for evaluating the adequacy of investment and its performance within firms. Despite of such a useful framework looking at investment on IT, IT portfolio in agriculture industry seems to be differentiated from other industries. In this study, we compared IT portfolios of farms: grain, field fruit and vegetable, greenhouse fruit, greenhouse vegetable, beef cattle and pig. We classified farms by their return on equity (ROE) in order to analyze the relationship between IT portfolio of each crop and performance. Then, we found patterns of IT portfolios of top-performance farms compared to all farms for each agricultural product. Lastly, peculiarities of each crop are interpreted and discussed to find out top-performance farms' IT investment patterns. From our study, it could be inferred that monotonous IT investments may not be as effective.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 1999년도 춘계공동학술대회:정보화시대의 지식경영
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• pp.152-153
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• 1999

• 한국경영과학회지
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• 제28권3호
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• pp.81-101
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• 2003

The financial statements purpose to provide useful information to decision-making process of business managers. The value-relevant information, however, embedded in the financial statement has been often overlooked in Korea. In fact, the financial statements in Korea have been utilized for nothing but account reports to Security Supervision Boards (SSB). The objective of this study is to develop earnings forecasting models through financial statement analysis using artificial intelligence (AI). AI methods are employed in forecasting earnings: artificial neural networks (ANN) for manufacturing industry and case~based reasoning (CBR) for banking industry. The experimental results using such AI methods are as follows. Using ANN for manufacturing industry records 63.2% of hit ratio for out-of-sample, which outperforms the logistic regression by around 4%. The experiment through CBR for banking industry shows 65.0% of hit ratio that beats the statistical method by 13.2% in holdout sample. Finally, the prediction results for manufacturing industry are validated through monitoring the shift in cumulative returns of portfolios based on the earning prediction. The portfolio with the firms whose earnings are predicted to increase is designated as best portfolio and the portfolio with the earnings-decreasing firms as worst portfolio. The difference between two portfolios is about 3% of cumulative abnormal return on average. Consequently, this result showed that the financial statements in Korea contain the value-relevant information that is not reflected in stock prices.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2008년도 정기학술발표대회 논문집
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• pp.572-577
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• 2008

한국 건설산업의 전략적 선진 프로젝트 매니지먼트 적용을 위해 유럽, 미국, 일본 등 선진국의 프로젝트 매니지먼트 지식체계를 비교 분석하였다. 그 결과 프로젝트 매니지먼트 지식체계의 이론적 배경 기반에는 '전략'의 '실행' 연계가 중요한 공통 이슈로 대두되며, 개별 프로젝트에서 복합 프로젝트를 관리 경영하는 통합 기반의 '프로그램 매니지먼트'와 선택과 집중을 하기 위한 '포트폴리오 매니지먼트'를 연계한 전략기획을 강조하고 있음을 알 수 있었다. 이에 본 연구에서는 한국 건설산업의 전략 실행을 위한 전략적 선진 프로젝트 매니지먼트 적용의 기본틀을 구축하고 현재 한국건설산업에 적용하기 위한 실천방안으로 1) 조직의 전략 실행을 위한 '이념과 철학' 구축으로 글로벌 경쟁력 혁신 2)조직의 문화와 구조를 고려한 전략적 '환경' 구축, 3) 조직의 실현 가능한 목표를 달성할 수 있는 전략적 '비전' 제시, 4)이러한 전략과 연계된 포트폴리오 매니지먼트를 통한 '투자', 5) 포트폴리오를 통한 프로그램, 프로젝트 매니지먼트 '실행' 그리고 마지막으로 이들의 통합체제 구축과 운영으로 '성과' 획득을 할 수 있도록 한국 건설산업의 전략적 선진 프로젝트 매니지먼트를 적용한 지속 가능한 발전 방안을 제시하였다.

• 한국안전학회지
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• 제27권4호
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• pp.121-127
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• 2012

Vehicle Inspection System is to examine the condition of vehicle regularly at the national level to protect lives and properties of the people from traffic accidents due to vehicle's fault. However, the vehicle inspection method, criteria, period and effectiveness have become a controversial issue, because of examining safety management of vehicle by drivers regardless of regular vehicle inspection. Therefore, the aim of this study is to investigate vehicle inspection timeliness and risk level of inspection items through basic statistical survey and portfolio analysis. The results of the research through practical analysis are: (1) The inspection failure rates between 3 and 6 model year tend to increase. (2) The failure of inspection items for safety highly impacts on traffic accident rate in terms of accident risks. (3) According to the result of portfolio analysis, faulty items located 1st quadrant are riding device, driveline system, controlling device, steering actuator, and fuel system.

• 한국공간정보시스템학회 논문지
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• 제9권3호
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• pp.81-89
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• 2007

본 논문은 품질기능전개(QFD)방법을 이용하여 기술포트폴리오를 분석하고 이를 바탕으로 차량항법 기술개발의 방향을 설정하고자 한다. 품질기능전개(QFD)방법은 고객의 요구와 관련된 기술적 역량을 연계 분석하는데 유용하게 사용된다. 우리는 본 논문에서 잠재고객을 대상으로 수요조사를 실시하고, 다양한 기초자료로 도출된 기술역량 데이터를 이용하여 기술포트폴리오 맵을 작성하고 분석하도록 한다. 그 결과에 의하면 영상HMI기술, 안전운전 지원기술, 단말정보관리기술 등이 상대적으로 기술적 역량과 기술 중요도가 모두 높은 유망한 투자대상 기술분야로 분석되었다.

• 아태비즈니스연구
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• 제11권4호
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• pp.37-48
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• 2020

Purpose - This study empirically investigates whether the risk property included in fat-tails of return distributions is systematic or unsystematic based on the devised statistical methods. Design/methodology/approach - This study devised empirical designs based on two traditional methods: principal component analysis (PCA) and the testing method of portfolio diversification effect. The fatness of the tails in return distributions is quantitatively measured by statistical probability. Findings - According to the results, the risk property in the fat-tails of return distributions has the economic meanings of eigenvalues having a value greater than 1 through PCA, and also systematic risk that cannot be removed through portfolio diversification. In other words, the fat-tails of return distributions have the properties of the common factors, which may explain the changes of stock returns. Meanwhile, the fatness of the tails in the portfolio return distributions shows the asymmetric relationship of common factors on the tails of return distributions. The negative tail in the portfolio return distribution has a much closer relation with the property of common factors, compared to the positive tail. Research implications or Originality - This empirical evidence may complement the existing studies related to tail risk which is utilized in pricing models as a common factor.

• Communications for Statistical Applications and Methods
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• 제28권1호
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• pp.59-79
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• 2021

Value at Risk (VaR) is one of the most common risk management tools in finance. Since a portfolio of several assets, rather than one asset portfolio, is advantageous in the risk diversification for investment, VaR for a portfolio of two or more assets is often used. In such cases, multivariate distributions of asset returns are considered to calculate VaR of the corresponding portfolio. Copulas are one way of generating a multivariate distribution by identifying the dependence structure of asset returns while allowing many different marginal distributions. However, they are used mainly for bivariate distributions and are not widely used in modeling joint distributions for many variables in finance. In this study, we would like to examine the performance of various copulas for high dimensional data and several different dependence structures. This paper compares copulas such as elliptical, vine, and hierarchical copulas in computing the VaR of portfolios to find appropriate copula functions in various dependence structures among asset return distributions. In the simulation studies under various dependence structures and real data analysis, the hierarchical Clayton copula shows the best performance in the VaR calculation using four assets. For marginal distributions of single asset returns, normal inverse Gaussian distribution was used to model asset return distributions, which are generally high-peaked and heavy-tailed.