• 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.

• Journal of Magnetics
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• v.12 no.2
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• pp.72-76
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• 2007

We investigate the spin transfer torque in metallic multilayer system by employing Keldysh non-equilibrium Green function method. We study the dependences of the spin transfer torque on the detailed energy configuration of ferromagnetic, spacer, and lead layers. With Keldysh non-equilibrium Green function method applied to a single band model, we explore spin transfer torque effect in various layer structures and for various material parameters.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.33 no.3
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• pp.137-145
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• 2010

The objective of this paper is to evaluate the equilibrium price between PSTN and VoIP telephony services in the case of non-linear utility function. Currently there are two types of wired phone services we are known PSTN (Public Switched Telephone Network) and VoIP (Voice over Internet Protocol). The PSTN telephony which provide high quality service and VoIP which provides relatively low quality service form a vertically differentiated oligopoly. Therefore, the evaluation of the equilibrium price between PSTN and VoIP services is very important to wired phone service providers. The equilibrium price depends on the state of the service cost function has been proved different value. This paper was evaluated each equilibrium price for the state of the linear cost function and non-linear cost function. Subsequently, this paper analyzed the demand of both services and the equilibrium profit which can maximize the profit of both service providers.

• Journal of Sasang Constitutional Medicine
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• v.21 no.3
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• pp.63-75
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• 2009

1. Objectives: This study was carried out to investigate the Sasang constitutional equilibrium functional difference according to drinking and smoking. 2. Methods: We analyzed the data of 300 adults(194 males, 106 females), who visited Cheonan oriental hospital of D univ. for medical examination, which includes Sasang constitution examination, equilibrium function test, questionnaire. We evaluationed the equilibrium function by measurement of open eyes and close eyes trace length, using the posturography system, according to drinking groups, smoking groups and drinking-smoking groups. 3. Results and Conclusions: The results were as follows : 1) In all subjects, trace length of heavy-drinker was significantly higher than non-drinker, trace length of smoker was significantly higher than non-smoker, trace length of drinker and smoker was significantly higher than non-drinker and non-smoker, trace length of male was significantly higher than female. 2) In Soyangin, trace length of middle-drinker was significantly higher than non-drinker. 3) In Taeumin, trace length of heavy-drinker was significantly higher than non-drinker, trace length of smoker was significantly higher than non-smoker, trace length of drinker and smoker was significantly higher than non-drinker and non-smoker. 4) In Soumin, trace length of drinker and smoker was significantly higher than non-drinker and non-smoker. The above results show that driking and smoking are one of main causes to decrease equilibrium function, specially the case of at once drinking and smoking are a potent influence. Also in Taeumin, comparing to different consitutions, the above results show that it is more obvious that drinking and smoking are influence on decrease of equilibrium function.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.7 s.124
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• pp.579-586
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• 2007

Analytical method to analyze the effect of tolerance on the modal characteristic of multi-body systems in dynamic equilibrium position is suggested in this paper. Monte-Carlo method is conventionally employed to perform the tolerance analysis. However, Monte-Carlo method spends too much time for analysis and has a greater or less accuracy depending on sample condition. To resolve these problems, an analytical method is suggested in this paper. Sensitivity equations for damped natural frequencies and the transfer function are derived at the dynamic equilibrium position. By employing the sensitivity information of mass, damping and stiffness matrices, the sensitivities of damped natural frequencies and the transfer function can be calculated.

• Bulletin of the Korean Mathematical Society
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• v.49 no.4
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• pp.749-759
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• 2012

A globally convergent algorithm for solving equilibrium problems is proposed. The algorithm is based on a proximal point algorithm (shortly (PPA)) with a positive definite matrix M which is not necessarily symmetric. The proximal function in existing (PPA) usually is the gradient of a quadratic function, namely, ${\nabla}({\parallel}x{\parallel}^2_M)$. This leads to a proximal point-type algorithm. We first solve pseudomonotone equilibrium problems without Lipschitzian assumption and prove the convergence of algorithms. Next, we couple this technique with the Banach contraction method for multivalued variational inequalities. Finally some computational results are given.

• Proceedings of the KOR-KST Conference
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• 2002.02a
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• pp.97-139
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• 2002

The aim of the present study is to find a good quality user equilibrium assignments under time varying condition. For this purpose, this study introduces a dynamic network loading method that can maintain correct flow propagation as well as flow conservation, and it develops a novel solution algorithm that does not need evaluation of the objective function by modifying the Schittenhelm (1990)'s algorithm. This novel algorithm turns out to be efficient and convenient compared to the conventional Frank-Wolfe (1956) algorithm because the former finds solutions based on routes rather than links so that it can maintain correct flow propagation intrinsically in the time-varying network conditions. The application of dynamic user equilibrium (DUE) assignment model with this novel solution algorithm to test networks including medium-sized one shows that the present DUE assignment model gives rise to high quality discrete time solutions when we adopt the deterministic queuing model for a link performance function, and we associate flows and costs in a proper way.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1193-1194
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• 2013

• Journal of Sasang Constitutional Medicine
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• v.22 no.4
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• pp.113-123
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• 2010

1. Objectives This study is about three cerebellar infarction patients with dizziness and ataxia. In this study, we evaluated the effects of Sasang constitutional treatment and suggested using the 'Equilibrium Function Test' as scale. 2. Methods These three patients were treated by Sasang constitutional herbal medications based on "Donguisusebowon". Acupuncture & moxa therapy and west medications were limited as much as possible. We evaluated the symptoms through two methods, the Visual Analogue Scale and the Equilibrium Function Test. 3. Results and Conclusions Dizziness and ataxia that were these three patients' chief complaints were improved. This case study shows that Sasang constitutional herbal medications are an effective treatment for cerebellar infarction patients.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.11
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• pp.630-635
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• 2004

Generation companies(Genco) submit the supply functions as a bidding function to a bid market in a competitive electricity market. The profits of Gencos vary in accordance with the bid functions, so the selection of a bidding function plays a key role in increasing their profits. In order to get a profitable bidding function which is usually linear, it is required to modify adequately the intersection and the slope of a linear supply function. This paper presents an analysis of the selection of the supply function from the viewpoint of Nash equilibrium(NE). Four types of bidding function parameters are used for analizing the electricity market. The competition of selecting bidding parameters is modeled as two level games in this research. One is a subgame where a certain type of parameters is given and the players compete to select values of the underlying parameters. The other is an overall game where the players compete to select a profitable type among the four types of parameters. The NEs in both games are computed by an using analytic method and a payoff matrix method. It is verified in case studies for the NE of overall game to satisfy the equilibrium condition.