• Journal of Information Processing Systems
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• v.14 no.2
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• pp.487-498
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• 2018

The purpose of the high-speed railway construction is to better satisfy passenger travel demands. Accordingly, the design of the train working plan must also take a full account of the interests of passengers. Aiming at problems, such as the complex transport organization and different speed trains coexisting, combined with the existing research on the train working plan optimization model, the multiobjective bi-level programming model of the high-speed railway passenger train working plan was established. This model considers the interests of passengers as the center and also takes into account the interests of railway transport enterprises. Specifically, passenger travel cost and travel time minimizations are both considered as the objectives of upper-level programming, whereas railway enterprise profit maximization is regarded as the objective of the lower-level programming. The model solution algorithm based on genetic algorithm was proposed. Through an example analysis, the feasibility and rationality of the model and algorithm were proved.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.1
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• pp.20-24
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• 2008

A bid-based pool(BBP) model is representative of energy market structure in a number of restructured electricity markets. Supply function equilibrium(SFE) models of interaction better match what is explicitly required in the bid formats of typical BBP markets. Many of the results in the SFE literature involve restrictive parametrization of the bid cost functions. In the SFE models, two parameters, intercept and slope, are available for strategic bidding. This paper addresses the realistic competition format that players can choose both parameters arbitrarily. In a fixed demand function, equilibrium conditions for generation company's profit maximization have a degree of freedom, which induces multi-equilibrium. So it is hard to choose a convergent equilibrium. However, consideration of stochastic demand function makes the equilibrium conditions independent each other based on the amount of variance of stochastic demand function. This variance provides the bidding players with incentives to change the slope parameter from an equilibrium for a fixed demand function until the slope parameter equilibrium.

• Korean Management Science Review
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• v.21 no.3
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• pp.13-22
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• 2004

We discuss that the proliferation of new types of retailers such as Internet shopping malls. home shopping systems, which use telecommunication media as means of providing information of products. makes delivery service generally available. Then. we show that the delivery service can be used strategically for profit maximization by intentionally homogenizing consumers and. furthermore, social welfare generally increases by this delivery service unless the cost of delivery service is higher than that of all consumer groups.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.398-399
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• 2006

The procurement of generation and transmission/Distribution capacity in vertically-integrated electric industry is sufficient by facility construction in suitable time. However, the introduction of competitive electricity market increase the efficiency of availability for facilities and fuels. As a result, long-term capacity procurement is required for stable demand-supply balance since it is expected to maintain their generation capacity at a minimum for profit maximization. In this paper, a new long-term capacity procurement mechanism is proposed, which is able to assure supplemental contribution in competitive electricity market.

• Journal of the Korean Institute of Intelligent Systems
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• v.11 no.5
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• pp.400-405
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• 2001

This paper addresses an effective approach of training neural networks classifiers for credit card fraud detection. The proposed approach uses evolutionary programming to trails the neural networks classifiers based on maximization of the detection rate of fraudulent usages on some ranges of the rejection rate, loot minimization of mean square error(MSE) that Is a common criterion for neural networks learning. This approach enables us to get classifier of satisfactory performance and to offer a directive method of handling various conditions and performance measures that are required for real fraud detection applications in the classifier training step. The experimental results on "real"credit card transaction data indicate that the proposed classifiers produces classifiers of high quality in terms of a relative profit as well as detection rate and efficiency.

• Proceedings of the KIEE Conference
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• 2001.05a
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• pp.108-111
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• 2001

The electric power industries in Korea are launched into deregulation by introducing the CBP(Cost Based Pool), where generation sector of KEPCO was divided into six generation companies and the other sectors of KEPCO remains vertically integrated system. In deregulated market, participants are concerned with maximization of their profit rather than minimization of system-wide costs. Consequently, there are difficulties in applying the cost minimization for the scheduling of generation resources to CBP, because of the operation of pumped-storage hydroplants. This paper presents an operation method of pumped storage hydroplants which is helpful for the economic operation of power system considering the market in the CBP.

• Korean Journal of Agricultural Science
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• v.15 no.2
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• pp.181-191
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• 1988

This paper aims to identify the farmers decision making under uncertainty. Qiuite a few studies have been done on the farmers decision making without uncertainty, but few studies have been made to see farmers decision making under uncertainty in Korea. There are many ways to avoid risks or uncertainty, Wald, Savage, Hurwicz, Laplace, Agrawl-Heady etc. are studied in this field. Fourty farmers were selected as samples. Among those half are the suburbs, and the other half are rural farmers. The results of this study are summarized as follows; First, the suburb farmers are more profit pursuit farmers. Second, not only the rural farmers but the suburb farmers are concerned more safety rather than output maximization. Third, the subsistence farmers and semi-commercial farmers are decided by Wald criterion, but the commercial farmers are decided by Savage or Laplace criterion. Fourth, information is very important in farmers decision making, but the creditability is far from satisfactory to the farmers.

• Journal of Korean Institute of Industrial Engineers
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• v.31 no.3
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• pp.248-256
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• 2005

In this paper, we compare two EOQ based inventory models under total cost minimization and profit maximization to investigate the difference in the optimal solutions. First of all, optimal solutions for both models through geometric programming (GP) techniques are found considering production (lot sizing) as well as marketing (pricing) decisions. An investigation of the effects of the changes in the optimal solutions according to varied parameters is performed by studying optimality conditions as well as by performing numerical analysis. We then conduct comparative analysis between the models to show the relationships between the optimal solutions of the models where certain conditions in the cost per unit and the demand per unit time are given. Several interesting economic implications and managerial insights are observed from this analysis.

• IE interfaces
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• v.14 no.4
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• pp.356-364
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• 2001

Production Improvement Method in TOC consists of five steps, but it is very difficult for most firms to implement it because it lacks the detailed methods at each step. This paper suggests some of detailed methods to implement the TOC. In the first step, computer simulation is used to identify the constraints in production lines. Subsequently, ASP, AUT, and CM calculation are defined for the second step, which are helpful to exploit the company's constraints. We also suggest the OEE method to effectively exploit the constraints of production lines in the factory. Finally the TOC/OEE procedure is suggested to optimize the investment in the fourth step. As an illustrative example, we introduce a case of a wafer manufacturer to adopt the suggested methods. The benefits of implementating the suggested methods are addressed in the framework of the balanced scorecard.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.6
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• pp.266-271
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• 2000

The electric power industries are moving from the conventional monopolistic or vertically integrated environments to deregulated and competitive environments, where each participant is concerned with profit maximization rather than system-wide costs minimization. Consequently, the conventional least-cost approaches for the generation resource schedule can not exactly handle real-world situations. This paper presents a game theory application for analyzing power transactions and market design in a deregulated energy marketplace, where the market participants determine the net profits through the optimal bidding strategies. The demand elasticity of the energy price is considered for the realistic modeling of the deregulated marketplace.