• Journal of Korean Philosophical Society
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• v.117
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• pp.1-33
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• 2011

Plato's political thought is developed in , and . He hopes 'justifiable state' that all citizens can get happiness. He suggests the plan of the ideal state. And the most important element in this ideal state is philosopher-king. His metaphysics, psychology and education theory are melted in philosopher-king. But in actual, the appearance of chis ideal ruler is impossible. Therefore he finds the second best state in . Then does Plato gives up his dream of the ideal state or approaches to that closely? And ruler stands against laws or relates with partnership? This article deals with these problems. As last, we will compare Plato's ideal state and philosopher-king to God's kingdom and Jesus in the Bible.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.12
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• pp.1759-1771
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• 2017

In this paper, an improved continuous integral variable structure systems(ICIVSS) with the prescribed control performance is designed for simple regulation controls of uncertain general linear systems. An integral sliding surface with an integral state having a special initial condition is adopted for removing the reaching phase and predetermining the ideal sliding trajectory from a given initial state to the origin in the state space. The ideal sliding dynamics of the integral sliding surface is analytically obtained and the solution of the ideal sliding dynamics can predetermine the ideal sliding trajectory(integral sliding surface) from the given initial state to the origin. Provided that the value of the integral sliding surface is bounded by certain value by means of the continuous input, the norm of the state error to the ideal sliding trajectory is analyzed and obtained in Theorem 1. A corresponding discontinuous control input with the exponential stability is proposed to generate the perfect sliding mode on the every point of the pre-selected sliding surface. For practical applications, the discontinuity of the VSS control input is approximated to be continuous based on the proposed modified fixed boundary layer method. The bounded stability by the continuous input is investigated in Theorem 3. With combining the results of Theorem 1 and Theorem 3, as the prescribed control performance, the pre specification on the error to the ideal sliding trajectory is possible by means of the boundary layer continuous input with the integral sliding surface. The suggested algorithm with the continuous input can provide the effective method to increase the control accuracy within the boundary layer by means of the increase of the $G_1$ gain. Through an illustrative design example and simulation study, the usefulness of the main results is verified.

• 한국전산유체공학회:학술대회논문집
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• 2008.03a
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• pp.1-13
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• 2008

An efficient segregated algorithm for the coupling of velocity and pressure of incompressible fluid flow, called IDEAL Inner Doubly-Iterative Efficient Algorithm for Linked-Equations), has been proposed by the present authors. In the algorithm there exist double inner iterative processes for pressure equation at each iteration level, which almost completely overcome two approximations in SIMPLE algorithm. Thus the coupling between velocity and pressure is fully guaranteed, greatly enhancing the convergence rate and stability of solution process. The performance of the IDEAL algorithm for three-dimensional incompressible fluid flow and heat transfer problems is analyzed and a systemic comparison is made between the algorithm and three other most widely-used algorithms (SIMPLER, SIMPLEC and PISO). It is found that the IDEAL algorithm is the most robust and the most efficient one among the four algorithms compared. This new algorithm is used for the velocity prediction of a new interface capturing method. VOSET, also proposed by the present author. It is found that the combination of VOSET and IDEAL can appreciably enhance both the interface capture accuracy and convergence rate of computations.

• 한국전산유체공학회:학술대회논문집
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• 2008.10a
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• pp.1-13
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• 2008

An efficient segregated algorithm for the coupling of velocity and pressure of incompressible fluid flow, called IDEAL (Inner Doubly-Iterative Efficient Algorithm for Linked-Equations), has been proposed by the present authors. In the algorithm there exist double inner iterative processes for pressure equation at each iteration level, which almost completely overcome two approximations in SIMPLE algorithm. Thus the coupling between velocity and pressure is fully guaranteed, greatly enhancing the convergence rate and stability of solution process. The performance of the IDEAL algorithm for three-dimensional incompressible fluid flow and heat transfer problems is analyzed and a systemic comparison is made between the algorithm and three other most widely-used algorithms (SIMPLER, SIMPLEC and PISO). It is found that the IDEAL algorithm is the most robust and the most efficient one among the four algorithms compared. This new algorithm is used for the velocity prediction of a new interface capturing method -VOSET, also proposed by the present author. It is found that the combination of VOSET and IDEAL can appreciably enhance both the interface capture accuracy and convergence rate of computations.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.2
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• pp.216-223
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• 2011

TVC is a kind of ejector which entrains low pressure working fluid by using the high pressure working fluid. While most papers relating with ejectors treat the working fluid as an ideal gas for convenience, the fluid doesn't behave as the ideal gas when phase change occurs. In this study, numerical analysis is conducted by applying Redlich-Kwong equation of state instead of ideal gas equation of state. Two turbulent models are compared for the better prediction and SST k-${\omega}$ model is preferred rather than realizable k-${\epsilon}$ model by comparison. Energy loss at the diffuser inlet and throat using the real gas equation of state is relatively greater than that using ideal gas law. For the real gas case, pressure increase due to shock train at the diffuser outlet is relatively smaller than the ideal gas case, but both cases have the same pressure increase due to a pseudo shock.

• SUVANNABHUMI
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• v.3 no.1
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• pp.25-46
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• 2011

The state-sangha relations in the countries of Theravada Buddhism has often been described as a mutually dependent patron-client relation in which the state and the sangha support each other by performing their due roles. Yet this theory involves a normative dimension that prescribes such a relation as the ideal in the Buddhist world. The explanatory power of this theory hence is hampered in a country where the ideal is not fully realized. In the wake of tumultuous political upheaval where political rivals vie for the state the ideal as well as the theory are put into a trial. The tragic history of modern Cambodia is a history of ceaseless conflict in which multiple contenders for the state had to define their relations with the sangha. The relations defined turned out less mutual than supposed. The state-sangha relations were rather unilaterally dependent. More often than not the sangha was subject to state control with no power to confront the state or coopted only to become a tool for political propaganda and manipulation. The sangha always played the role of client, waiting for the state to define the relation and to be benevolent. Even when the monks were forced to disrobe and when the sangha itself was annihilated, all they did was to wait for another patron state that would put the sangha back in place. The state-sangha relations the Cambodian history reveals were not close to one in which the two parties benefit each other on an equal basis. It was a patron-client relationship in which the client sangha had to be heavily dependent on the patron state. Such a unilaterally dependent relationship is the one that has prevailed in Cambodia.

• Journal of Power Electronics
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• v.17 no.5
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• pp.1308-1316
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• 2017

The distributed maximum power point tracking (DMPPT) concept is widely adopted in photovoltaic systems to avoid mismatch loss. However, the high cost and complexity of DMPPT hinder its further promotion in practice. Based on the concept of DMPPT, this paper presents an integrated submodule level half-bridge stack structure along with an optimal current point tracking (OCPT) control algorithm. In this full power processing integrated solution, the number of power switches and passive components is greatly reduced. On the other hand, only one current sensor and its related AD unit are needed to perform the ideal maximum power generation for all of the PV submodules in any irradiance case. The proposal can totally eliminate different small-scaled mismatch effects in real-word condition and the true maximum power point of each PV submodule can be achieved. As a result, the ideal maximum power output of the whole PV system can be achieved. Compared with current solutions, the proposal further develops the integration level of submodule DMPPT solutions with a lower cost and a smaller size. Moreover, the individual MPPT tracking for all of the submodules are guaranteed.

• Journal of Korean Home Economics Education Association
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• v.29 no.2
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• pp.85-111
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• 2017

The purpose of this study was to examine the need of the ideal human being and to establish ideal desirable state of affairs in the ideal portrait of a human being for pursuing in the home economics education. This study analyzed the deducted issue from the discussion about the human being in the educational research through the national curriculum and literature review. The desirable state of affairs established in this research are (1) it needs to reflect the feasibility aspect for actual implementation, (2) it needs to consider the contextual subject aspect, and (3) the curriculum view containing the philosophy of the subject, that is, critical science perspective shall be reflected on the desirable human being. The ideal portrait of a human being was stated, in the individual family, society nation, cultur e world according to subcategories. In addition, the stated ideal portrait of a human being was modified through expert consultations. The proposal was reexamined for the validity of the statement and restated as a comprehensive statement of an ideal portrait of a human being that included a restatement of the three areas. An ideal portrait of a human being pursuing in home economics education from a core value of curriculum stated as 'a person who has solved the practical problem actively'.

• Bulletin of the Korean Mathematical Society
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• v.31 no.2
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• pp.210-214
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• 1994

The purpose of this paper is to investigate the relationship between the depths of the Rees algebra R[It] and the associated graded ring g $r_{I}$(R) of an ideal I in a local ring (R,m) of dim(R) > 0. The relationship between the Cohen-Macaulayness of these two rings has been studied extensively. Let (R, m) be a local ring and I an ideal of R. An ideal J contained in I is called a reduction of I if J $I^{n}$ = $I^{n+1}$ for some integer n.geq.0. A reduction J of I is called a minimal reduction of I. The reduction number of I with respect to J is defined by (Fig.) S. Goto and Y.Shimoda characterized the Cohen-Macaulay property of the Rees algebra of the maximal ideal of a Cohen-Macaulay local ring in terms of the Cohen-Macaulay property of the associated graded ring of the maximal ideal and the reduction number of that maximal ideal. Let us state their theorem.m.m.

• Journal of the Korean housing association
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• v.14 no.6
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• pp.105-114
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• 2003

This study aims to investigate the thoughts of the utopians for the ideal community in 19th century. Around late 18th century, the ideal community proposals by the utopians were coming out as an alternative to reform the social and economical structure. The experimental community proposals which suggested by the utopian socialists such as Robert Owen and Charles Fourier took their emphasis on the social reform to improve the environment of work in terms of social and economical organization. While the thoughts of ideal community showing up in the literature by utopians were based on the state socialism that accompanied by the ultimate corrective system of production and distribution and the unified social system, the physical organization was described in more detail without a restriction in contrast to the real proposals for the ideal community. Based on the experimental community and the ideal community in the literature in 19th century, the urban model of late 19th century were proposed as a real community model. With the optimistic belief to the technological development resulted from the Industrial Revolution, the urban models of utopia placed greater emphasis on the physical organization than the previous ideal communities in 19th century and had much influence on the modern urban planning in 20th century.