• Journal of Digital Convergence
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• v.9 no.5
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• pp.21-30
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• 2011

Broadcasting contents market is changing back of a smart TV appearance recently. This study proposed a contents industry view and government policy direction. We accomplished an depth interview with expert of Broadcasting Content Production Support. The data analysis method executed the content analysis. The research results presented in a three direction.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1995.10a
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• pp.171-177
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• 1995

Fracture mechanics does work for concrete, provided that one uses a proper, nonlinear form of fracture mechanics in which a finite nonlinear zone at fracture front is being considered. The fracture process zone is a region ahead of a traction-free crack, and the development of model of fracture process zone is most important to describe fracture phenomena in concrete. This paper is about fracture behavior of concrete cylinder under lateral pressure. Concrete cylinders were made of high strength normal connote, steel fiber reinforced concrete and steel fiber reinforced polymer-impregnated concrete and concrete and the fracture behavior such as cracking propagation and ultimate load are observed. The fracture process zone is modelled by a Dugdale-Barenblatt type model with linear tension-softening curve and are implemented to the boundary element technique for the fracture analyses of the cylinders. The experimental results are compared with analysis results and tension-softening curves for the steel fiber reinforced concrete and steel fiber reinforced polymer-impregnated concrete are obtained by back analyses.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.579-584
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• 2004

In development of the bogie, the fatigue strength of the bogie frame is an important design criteria. Also the bogie frame weight reduction is required in order to save energy and materials. In this study. structural analysis of bogie frame by using the finite element method has been performed for the various loading conditions according to the UIC standards and it has been attempted minimize the weight of bogie frame by back-propagation neural network and genetic algorithm. Finite element mesh generation and finite element analysis were performed by Altaire Hyper Mesh and ABAQUS.

• Journal of international Conference on Electrical Machines and Systems
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• v.3 no.1
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• pp.20-26
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• 2014

To enhance torque density by harmonic current injection, optimal slot/pole combinations for five-phase permanent magnet synchronous motors (PMSM) with fractional-slot concentrated windings (FSCW) are chosen. The synchronous and the third harmonic winding factors are calculated for a series of slot/pole combinations. Two five-phase PMSM, with general FSCW (GFSCW) and modular stator FSCW (MFSCW), are analyzed and compared in detail, including the stator structures, star of slots diagrams, and MMF harmonic analysis based on the winding function theory. The analytical results are verified by finite element method, the torque characteristics and phase back-EMF are also taken into considerations. Results show that the MFSCW PMSM can produce higher average torque, while characterized by more MMF harmonic contents and larger ripple torque.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.852-854
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• 2000

The paper is described about the statatic and dynamic characteristics analysis of Transverse Swithed Reluctance Motor(TSRM). To investigate the nonlinearity of magnetic circuit, parameters of the modeling are computed by the finite element method as functions of input current and angular displacement. The current, torque, back EMF and output power wave of TSRM are simulated from the motion equation by MATLAB/Simulink.

• Proceedings of the IEEK Conference
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• 2000.07b
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• pp.1045-1048
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• 2000

This paper presents the application of the wavelet transform analysis and the neural network method to the phonocardiogram (PCG) signal. Heart sound is a acoustic signal generated by cardiac valves, myocardium and blood flow and is a very complex and nonstationary signal composed of many source. Heart sound can be discriminated normal heart sound and heart murmur. Murmurs have broader frequency bandwidth than the normal ones and can occur at random position of cardiac cycle. In this paper, we classified the group of heart sound as normal heart sound(NO), pre-systolic murmur(PS), early systolic murmur(ES), late systolic murmur(LS), early diastolic murmur(ED). And we used the wavelet transform to shorten artifacts and strengthen the low level signal. The ANN system was trained and tested with the back- propagation algorithm from a large data set of examples-normal and abnormal signals classified by expert. The best ANN configuration occurred with 15 hidden layer neurons. We can get the accuracy of 85.6% by using the proposed algorithm.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.51 no.1
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• pp.1-9
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• 2002

This paper describes for new design method to improve respones characteristics of moving-magnet type LDM with volume reduction of slider back iron. To achieve the constant thrust of LDM through restraining saturation at the center core of stator excitation coil, double sided stator winding of LDM is proposed. We constructed new type LDM to prove the validity of design process. Analysis results through measurement and simulation of proposed multi-separated winding LDM were proved excellent in response characteristics and static thrust.

• Journal of Power Electronics
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• v.16 no.1
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• pp.48-56
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• 2016

This paper proposes a method for detecting irreversible demagnetization using the harmonic analysis of back electromotive force (BEMF) in interior permanent magnet-type brushless DC motors. First, demagnetization patterns, such as equality, inequality, and weighted demagnetizations, are defined and classified by considering the possibility of demagnetization resulting from motor operating characteristics. Second, an available diagnostic model for the harmonic analysis of BEMFs is defined according to pole-slot coefficients because the characteristics of BEMFs under demagnetization conditions are affected by the combination of poles and slots. Third, BEMFs and their harmonic components under normal and demagnetization conditions are analyzed through simulation and experiment to verify the proposed demagnetization detection technique.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.1057-1059
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• 2003

This paper presents drive analysis of slotless air-cored PM linear synchronous motor using two-dimensional analytical method. In order to calculate dynamic characteristic, back-EMF and linkage flux are calculated by Permanent Magnet Field and also inductance are given by slotless winding current coil. PMLSM drive simulation is performed by PI control system.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.756-758
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• 2003

In the machine tool industry, direct drive linear motor technology is of increasing interest as a means to achieve high acceleration, and to increase reliability. This paper deals with the characteristics of tubular type linear oscillating actuator with Halbach magnet array. The magnetic field solutions are derived analytically in terms of vector potential, two dimensional cylindrical coordinate system and Maxwell's equations. Motor thrust, flux linkage, back emf are then derived. The results are shown in good conformity with those obtained from the commonly used finite element method. Test results such as thrust measurements are also given to confirm the analysis.