• Proceedings of the KIEE Conference
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• 2006.11a
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• pp.393-395
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• 2006

In competitive market, it is important to establish a plan of transmission expansion considering uncertainty of future generation and load behavior. For this reason, revised transmission expansion model is proposed in this paper. In the proposed model, information of predictable future condition are included in a cost function of transmission expansion investment. Also, to reduce risk of the investment, mean-variance Markowitz approach is added to the objective function of cost. By optimization programming, the most robust and the minimum cost plan can be obtained.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.10
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• pp.1703-1711
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• 2010

Electric power utilities are facing increasing uncertainties regarding the economic, political, societal, environmental constraints under they operate and plan their future systems. The utilities have to integrate consumers' interruption cost representing reliability worth of electricity into the process of determining the optimum investment level. In order to do so, the estimated outage cost must be included into quantitative index corresponding to system capital and operation investment cost to establish an optimal expansion plan. This paper is a study on the outage cost assessment by using macro approach for calculating IEAR(Interrupted Energy Assessment Rates) and the TRELSS(Transmission Reliability Evaluation for Large-Scale Systems) program was used to calculate EENS(Expected Energy Not Served).

• KIEE International Transactions on Power Engineering
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• v.5A no.2
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• pp.199-203
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• 2005

This paper proposes the level of price cap in the TWBP(Two- Way Bidding Pool) market in Korea for which the draft of market design has been prepared by KPX. Max - GMCP(Maximum Generation Market Clearing Price) and APC(Administered Price Cap) would be separately applied as individual price caps for a normal period and a Price Capping period in TWBP. The level of price cap is determined for inducing optimal investment in the Korean Electricity Market considering the 'electricity resource baseline plan' published by the Korean government in 2002 for maintaining government-leading resource planning in Korea. In this regard, Max - GMCP is calculated from the equilibrium condition of investment based on reliability standard and fixed cost of the peaking plant. For verifying the propriety of the proposed price cap, this paper compares the proposed value with the estimated VoLL(Value of Lost Load) based on Korea's GDP(Gross Domestic Product).

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.12
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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.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.842-843
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• 2007

In this paper, the proper rebate level can be decided in programs of energy savings by solving an optimization problem with an objective function, which satisfies a maximum value of total energy savings. And then, each prevalence amount is estimated by using virtual Bass model which is a function of rebate level, instead of the conventional Bass model. Finally, by cost/benefit analysis of the estimated prevalence amounts, the priority order is obtained for the investment of each program. The priority order obtained in this way may result the improvement of investment efficiency for DSM(Demand-Side Management) programs and the reasonable plan decision for supply and demand in power system.

• Child Health Nursing Research
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• v.15 no.1
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• pp.42-52
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• 2009

Child is a being and provides the genetic continuity of parents and society, and therefore the fitness of these children for survival, growth and development towards reproduction, is of significance to parents and society. The aim of health care for high-risk children is not only to minimize or eliminate health problems, but also to optimize their fitness. Considering that the health care of children is influenced by available resources of parents and society, and sociocultural values and paradigms in a given environment of evolutionary adaptedness (EEA), child health care professionals need to understand factors affecting the optimal fitness of children with risks. This paper introduces a new integrated theory for health care in high-risk children, entitled, Health for Optimal Fitness of High-Risk Children. Five main components were identified with associate concepts or midrange theories affecting heath for optimal fitness of high-risk children; EEA, optimal fitness, health problems, investment resources, and anthropological values. It may provide an integrated perspective on health of high-risk children in both the proximately biomedical approach and ultimately evolutionary approach as optimizing their fitness. Further study is needed to develop substantial statements between components with existential examples.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.117-119
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• 1995

For an effective application of the cogeneration system for commercial and industrial buildings, we need to develop a relevant model to determine the long-term based optimal sizing of the cogeneration system considering electrical and thermal load demands, buy and sell contracts with electric utility and the annual production cost. In assessing the optimal sizing of cogeneration, we have to consider both economic parameters and their capacity expansion for the increased electrical and thermals demand in the future. In this paper, we propose a mathematical model for the optimal sizing of cogeneration systems considering annual production costs and other economic parameter such as, lifetime of the equipment, time value of the capital, etc. In the case study, we thoroughly examine the effects of the economic parameters and determine the optimal size of the sample system. In addition, we calculate the payback period of the cogeneration investment.

• Journal of Convergence Society for SMB
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• v.4 no.3
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• pp.33-39
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• 2014

The Purpose of this study is to investigate the problems arising during the investment decision making on maintaining and improving Manufaturing information systems. The detailed problem considered in this study is to determine the priorities of various investment alternatives on improving Manufacturing systems. For this purpose, this study suggests a systematic procedure in which the analytic hierachy process is used to fix the important weights of alternatives, together with a normalization step, and then an integer programming model to select the optimal set of alternatives that maximize the total priority while satisfying the allowable budget and the time limitation.

• Journal of agriculture & life science
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• v.46 no.3
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• pp.143-151
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• 2012

This paper analyzes whether under-investment due to hold-up exists in broiler industry or not by using survey data on broiler growers. When a grower who has facilities to be required for contract is aware of the possibility of being held-up by an integrator, he/she may invest in relation-specific asset less than is optimal. The result shows that when a grower thinks that finding a new integrator in the region is difficult after the current contract being terminated, under-investment exists. When a grower has the experience that a current integrator required her/him to do something not written on the contract, she/he may have invested less. However it is not statistically significant.

• Journal of the Korea Convergence Society
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• v.12 no.4
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• pp.249-258
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• 2021

Bitcoin prices have been soaring recently as investors flock to cryptocurrency exchanges. The purpose of this study is to predict the Bitcoin price using a deep learning model and analyze whether Bitcoin is profitable through investment strategy. LSTM is utilized as Bitcoin prediction model with nonlinearity and long-term memory and the profitability of MA cross-over strategy with predicted prices as input variables is analyzed. Investment performance of Bitcoin strategy using LSTM forecast prices from 2013 to 2021 showed return improvement of 5.5% and 46% more than market price MA cross-over strategy and benchmark Buy & Hold strategy, respectively. The results of this study, which expanded to recent data, supported the inefficiency of the cryptocurrency market, as did previous studies, and showed the feasibility of using the deep learning model for Bitcoin investors. In future research, it is necessary to develop optimal prediction models and improve the profitability of Bitcoin investment strategies through performance comparison of various deep learning models.