• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.3
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• pp.34-39
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• 2008

The purpose of this paper is characteristic analysis of multi-disk axial-gap pm motor for turbo compressor. The axial-gap permanent magnet motor has shown a growing interest in high-speed application for its high-efficiency, compact size and low vibration characteristics due to core-less structure. To achieve high-power, the axial-gap PM motor has multi-disk structure of stator and rotor disk. Because of its complicated magnetic flux path, it is not easy to calculate a dynamic characteristics using finite element analysis. In this paper, the simplified 2-D unfolded model to predict EMF characteristic is presented. To verify thesuggested 2-D unfolded model analysis of back-EMF characteristic was calculated and compared 3-D finite element. Finally the proposed method is verified by experimental results and shows good agreement with test results.

• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.200-203
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• 2002

This paper presents Continuous-current mode of $S^4$-PFC(Single-Stage Single-switch Power Factor Correction) converter. Proposed converter operates in the continueous current mode(CCM) at full load and discontinuous current mode(DCM) at light load. So, characteristic of proposed converter is no bus voltage stress and Zero Voltage Switching(ZVS) using resonant auxiliary circuit. And. This paper presents characteristic of $S^4$-PFC converter and effect of circuit parameter of proposed converter through the input inductor, PFC capacitor's variation. All of these theory and characteristic verified through the experiment with a 72W(12V, 6A), $90^{kHz}$ prototype converter.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.50 no.4
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• pp.179-187
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• 2001

In recent years, the switching source devices have the advantage of small, light and high reliability with the high-frequency. But, high-frequency switching has disclosed disadvantage of result from stress and turn-on and turn-off peak losses at the switching instant. Accordingly, in this paper propose ZVS-HB type high-frequency resonant DC/DC converter using soft switching technique (Zero-Voltage-Switching, Zero-Current-Switching) with safety operating of circuit at diving on inductive zone, through the circuit design example using the capacitor $C_3,\;C_4$ with soft switching function and division characteristic of resonant Capacitor C, $C_1,\;C_2$, and, the characteristic analysis of circuit is generally described using normalized parameters. Also, this paper certified a rightfulness of characteristic analysis in comparison with a theoretical values and a experimental values obtain from experiment using MOSFET.

• Communications of the Korean Mathematical Society
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• v.11 no.4
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• pp.1159-1174
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• 1996

The spectrum of the Laplacian matrix of a graph gives an information of the structure of the graph. For example, the product of non-zero eigenvalues of the characteristic polynomial of the Laplacian matrix of a graph with n vertices is n times of the number of spanning trees of that graph. The characteristic polynomial of the Laplacian matrix of a graph tells us the number of spanning trees and the connectivity of given graph. in this paper, we compute the characteristic polynomial of the Laplacian matrix of a graph bundle when its voltage lie in an abelian subgroup of the full automorphism group of the fibre; in particular, the automorphism group of the fibre is abelian. Also we study a relation between the characteristic polynomial of the Laplacian matrix of a graph G and that of the Laplacian matrix of a graph bundle over G. Some applications are also discussed.

• Proceedings of the KIEE Conference
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• 2002.04a
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• pp.119-122
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• 2002

This paper presents detailed characteristic of a Reluctance Synchronous Motor(RSM) which has a transverse-laminated rotor. First of all, the analysis of a magnetic circuit field between stator and rotor should be achieved in order to predict the performance characteristic of the RSM. For the analysis of a magnetic circuit field, the Finite Element(FE) analysis and a experimental method are used. The analytical result of the inductance flux distribution, vector potential, and the output shows some good characteristic along with the load condition.

• Communications for Statistical Applications and Methods
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• v.21 no.3
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• pp.213-224
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• 2014

In this paper, we study the problem of transforming to normality. We propose to estimate the transformation parameter by minimizing a weighted squared distance between the empirical characteristic function of transformed data and the characteristic function of the normal distribution. Our approach also allows for other symmetric target characteristic functions. Asymptotics are established for a random sample selected from an unknown distribution. The proofs show that the weight function $t^{-2}$ needs to be modified to have thinner tails. We also propose the method to compute the influence function for M-equation taking the form of U-statistics. The influence function calculations and a small Monte Carlo simulation show that our estimates are less sensitive to a few outliers than the maximum likelihood estimates.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2002.05a
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• pp.205-211
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• 2002

The purpose of this paper is 1) to extract managerial factor into each cell which is classified by the characteristic grill of new products 2) to construct a management model of new product development for korean companies. For this purpose, the characteristic grill of new products is classified by which is market/technology sphere. Moreover the focus of this analysis is on examination of success/failure factors, which have an important effect upon new product success or failure. The variables for this study were selected from literature survey and pre-interview was implemented specially. The subject of study was project leaders of electronics industry where have taken the leading part in product development activities in Korean manufacturing industries. Enquete survey was conducted in each firm and project managers were asked to respond. Conclusion of this study based on many significant results gained by the various multi-variate analysis are summarized as follows. First, it can he noted that success/failure factors are different by each classified model and characteristic grill of a new product. Second, it has been identified that the important factors of success products were technical & management support and market ability, the important factor of failure product were lacking in ability of technical development and R&D management system construction. This paper presents some useful guidelines in strategic and managerial aspects for development of new products. Concurrently, the model of this study should be a great practical approach for application of actual affairs.

• Progress in Superconductivity and Cryogenics
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• v.8 no.3
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• pp.59-62
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• 2006

For electric power applications of Bi-2223/Ag superconducting tapes, a transport characteristic is important issue. A transport characteristic is strongly depends on the magnitude and direction of external time-varying magnetic field. To verify a effect of external magnetic field, we manufactured a prototype magnet and obtained transport characteristics with respect to the magnitude, the direction and the frequency of external magnetic field. The data acquired in this paper will be used as a source for the study of HTS electric power applications which is supposed to carry on.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.894-895
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• 2015

This paper deals with the characteristic analysis & optimum design of Permanent Magnet Assisted Synchronous Reluctance Motor(PMASynRM) for Premium Efficiency Performance. The focus of this paper is characteristic analysis of d and q-axis inductances and torque according to magnetizing quantity of interior permanent magnet for PMASynRM. The d and q-axis current component ratios, load angles of a PMASynRM are investigated quantitatively on the basis of the proposed analysis method and the experimental test. Comparisons are given with output characteristic curves of PMASynRM and those according to the rated wattage in PMASynRM, respectively. And optimum design of PMASynRM is performed by Response Surface Methodology(RSM).

• Journal of the Korean Society of Costume
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• v.45
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• pp.161-178
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• 1999

In contemporary fashion metal have used which is as the material with a sufficient potentiality of expression which is displayed by an unique characteristic involved only in metal. In this paper metal expressed in contemporary fashion is researched. The first thing the formative characteristic of metal is researched under the consideration of type technique and color of metal used in contemporary fashion. Metals such as gold silver bronze aluminum thin lead and iron are usually used in fashion and those metals are used in various types such a thread fabric board leaf a and cable. Those types of metal as above are applied to the clothing by the techniques of weaving embroidering metal leaf printing or moulding which gives the formative characteristic to the clothing. In color metal has an effect on the colors of surroundings by its smooth and unique luster and its effect of reflection and produces the visual formative characteristic through the effects of contrast. The esthetic will of metal expressed in modern fashion is researched in this study under the facts studied as above. first metal expresses the future oriented esthetic Second metal has the characteristic of attracting the attention Third metal is used as valid techniques to express the artistic formation for clothing escaping from the idea that the clothing is only for wearing. Finally metal is used as an anti-cultural tool of fighting against the existing order or spirit.