• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.578-580
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• 2003

This paper describes a research for activation of diect load control program in competitive electicity market. A direct load control program after the restructuring of electric power industry will evolve to the bilateral information system to derive a voluntary participation of demand side resource. Therefore, this paper presented a right way of direct load control program for the foreign market research.

• 한국시뮬레이션학회논문지
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• 제11권2호
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• pp.55-66
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• 2002

VHDL has been. widely used in modeling and simulation of hardware designs. However, complex relationship between components of the designs makes the VHDL modeling problem very difficult. Furthermore, after the initial creation of VHDL models, they evolve into many versions over their lifetime. To cope with such difficulties, this paper proposes a new methodology for the management of VHDL models supporting versions. Its conceptual bases are system entity structure and relational database. Within the methodology, a family of hierarchical structures of a design is organized in the form of VHDL model structure. It is, in turn, represented in the form of relational tables. Once the model structure is built in such a way, a specific simulation model which meets design objective is pruned from the model structure. The details of VHDL codes are systematically synthesized by combining it with the primitive models in a model base. These algorithms are also defined in terms of relational algebraic operations.

• ETRI Journal
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• 제33권2호
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• pp.240-250
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• 2011

To enable a relevance feedback paradigm to evolve itself by users' feedback, a reinforcement learning method is proposed. The feature space of the medical images is partitioned into positive and negative hypercubes by the system. Each hypercube constitutes an individual in a genetic algorithm infrastructure. The rules take recombination and mutation operators to make new rules for better exploring the feature space. The effectiveness of the rules is checked by a scoring method by which the ineffective rules will be omitted gradually and the effective ones survive. Our experiments on a set of 10,004 images from the IRMA database show that the proposed approach can better describe the semantic content of images for image retrieval with respect to other existing approaches in the literature.

• Bulletin of the Korean Chemical Society
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• 제34권2호
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• pp.574-578
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• 2013

In this work, the friction and diffusion coefficients of a tracer in a mesoscopic solvent are evaluated as a function of the tracer size by a hybrid molecular dynamics simulation where solute molecules evolve by Newton's equations of motion but the solvent evolves through the multi-particle collision dynamics. The friction coefficient is shown to scale linearly with the tracer size for larger tracers in accord with predictions of hydrodynamic theories. The diffusion coefficient of tracer is found to be inversely proportional to tracer size. The behavior of Stokes-Einstein formula is validated as a function of tracer size.

• 천문학회지
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• 제36권3호
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• pp.241-248
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• 2003

Owing to several observational evidences and theoretical predictions for morphological evolution of galaxies, it is now widely accepted that galaxies do evolve from late types to early ones along the Hubble sequence. It is also well established that non-axisymmetric potentials of bar-like or oval mass distributions can change the morphology of galaxies significantly during the Hubble time. Here, we review the observational and theoretical grounds of the secular evolution driven by bar-like potentials, and present the results of SPH simulations for the response of the gaseous disks to the imposed potentials to explore the secular evolution in the central regions of barred galaxies.

• 천문학논총
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• 제30권2호
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• pp.215-216
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• 2015

Close binary stars are so close that one component has an effect on the evolution of the other. But how do they form and evolve? This is an unsolved problem. One speculation is that the binary is a part of a hierarchical triple and its orbit shrinks due to interaction with the third component. Therefore, searching for and investigating tertiary components, especially close-in ones, in close binary stars are important for understanding their origin, as well as to test theories of star formation and stellar dynamical interaction.

• 한국수학교육학회지시리즈E:수학교육논문집
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• 제16권
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• pp.1-65
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• 2003

The focus of this article is on the process of cultivating students' interests so that they come to view mathematics as an activity worthy of their engagement. We first define and operationalize the notion of interests, in the process developing a perspective in which they are seen to be generative, to evolve, and to be deeply cultural. We concretize this perspective by presenting an analysis of a classroom design experiment that documents both the process by which the students' interests evolved and the means by which these developments were supported. We then frame the analysis as a case in which to tease out the implications for a nascent design theory of mathematical interests and in doing so give particular attention to the issue of equity in students' access to significant mathematical ideas

• 한국주거학회:학술대회논문집
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• 한국주거학회 2001년도 학술발표대회논문집
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• pp.119-127
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• 2001

This paper aims to analyse the changes In the living arrangements of the elderly in Chejoo-do for the elderly housing supply by using census data. The conclusions are as follows; The rate of living alone and living with spouse only of the elderly have been increasing. The trend in county was higher than that in city. Living alone rate of the elderly of Chejoo-do was higher than that of Korean average. Even in the oldest old, living alone rate has been increasing in Chejoo-do. It is a unique phenomenon in Korea and similar with U.S. In Chejoo-do, it is strongly required to evolve elderly housing by universal design for living alone elderly in county as well as for living alone elderly in city.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1998년도 추계학술대회 학술발표 논문집
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• pp.553-559
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• 1998

Simple Genetic Algorithm(SGA) proposed by J. H. Holland is a population-based optimization method based on the principle of the Darwinian natural selection. The theoretical foundations of GA are the Schema Theorem and the Building Block Hypothesis. Although GA goes well in many applications as an optimization method, still it does not guarantee the convergence to a global optimum in some problems. In designing intelligent systems, specially, since there is no deterministic solution, a heuristic trial-and error procedure is usually used to determine the systems' parameters. As an alternative scheme, therefore, there is a growing interest in a co-evolutionary system, where two populations constantly interact and co-evolve. In this paper we review the existing co-evolutionary algorithms and propose co-evolutionary schemes designing intelligent systems according to the relation between the system's components.

• 천문학회보
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• 제36권1호
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• pp.47.2-47.2
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• 2011

Gravitational waves from the pulsar glitch can be detected by next generation gravitational wave observatories. We investigate characteristics of the modes that can emit the gravitational waves excited by three different types of perturbations satisfying conservation of total rest mass and angular momentum. These perturbations mimic the pulsar glitch theories i.e., change of moment of inertia due to the star quakes or angular momentum transfer by vortex unpinning at crust-core interface. We carry out numerical hydrodynamic simulations using the pseudo-Newtonian method which makes weak field approximation for the dynamics, but taking all forms of energies into account to compute the Newtonian potential. Unlike other works, we found that the first and second strongest modes that give gravitational waves are $^2p_1$ and $H_1$ rather than$^2f$. We also found that vortex unpinning model excites the inertial mode in quadrupole moment quite effectively. The inertial mode may evolve into the non-axisymmetric r-mode.