• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.12
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• pp.1218-1229
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• 1991

The time optimal position control design can be repeatedly taken from the initial state of a dynamic system to a desired one as fast as possible in the industrial drives. In this case, an induction machine parameters will vary due to temperature, frequency, and saturation effects. In particular, the rotor resistance changes critically with temperature and frequency. These changes affect the command values of the stator current components and slip speed. There is a mismatch between the commanded variables and actual ones of the induction motor drive, and this situation leads to coupling of the vector controller from the plant, i.e. the induction motor . Consequences of such a coupling include the initiation of oscillations of the rotor flux and unsuitable switching of electromagnetic torque for the induction motor servo drive. Therefore, this paper describes a rotor resistance parameter compensating method for the induction motor, And the validity of the proposed design method is confirmed by simulation studies and experiment results.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.1099-1100
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• 2008

In this paper, we would like to introduce a simple and low cost wired pointing device by using a electromagnetic induction. A number of patents of Wacom describe electronic drawing devices or styluses. The movement of the stylus over a tablet is traced electronically and used applied to a resonant circuit in the stylus. Electromagnetic radiation emitted by the resonant circuit is detected by a sensing mechanism and location processing is used to locate the stylus. In this research, difference coil principle is used to detect the emitted radiation of the resonant circuit in the pen. This detection device shows good performance to detect the location of the pen on the tablet.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.26-29
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• 2001

In this paper, a brief overview of problems related to the electromagnetic, mechanical design criteria is reported. Also, we described the results about the comparisons between BLDC motor and induction motor for Turbo Compressor considering motor cost, efficiency and reliability. As a result, we select an induction motor for 12.5RT Turbo compressor for the application of small building's all-conditioning system. Finally, a prototype induction motor was manufactured and tested under compressor set. The test results were successfully met the mechanical, thermal and electromagnetic point of view.

• Journal of the Earthquake Engineering Society of Korea
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• v.9 no.1 s.41
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• pp.51-59
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• 2005

Magnetorheological(MR) dampers are one of the most promising semi active control devices, because they have advantages such as small power requirement, reliability, and low price to manufacture. To reduce the responses of structures with MR dampers, a control system including power supply, controller, and sensors is required. However, when a mount of MR dampers are used to a large?scale civil structure such as cable stayed bridges, the control system becomes complex. Therefore, it is not easy to install and maintain the MR damper based control system. To resolve above difficulties, This paper proposes a smart passive system that consists of a MR damper and an electromagnetic induction(EMI) system. According to the Faraday’s law of induction, EMI system that is attached to the MR damper produces electric energy. The produced energy is supplied to the MR damper. Thus, the MR damper with EMI system does not require any power at all. Furthermore, the induced electric energy is proportional to external loads like earthquakes, which means the MR damper with EMI system is adaptable to external loads without any controller and corresponding sensors. Therefore, it is easy to build up and maintain the proposed smart passive system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.640-645
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• 2020

To produce an input device stably using the transparent electromagnetic pattern of an electromagnetic induction method, pattern inspection is required in advance in the production process. Various methods of inspecting the capacitive pattern for hand-touch have been proposed, but it is difficult to find the related technical data for the pattern inspection method of the transparent electromagnetic induction method. In this study, to develop an inspection system for a fused electromagnetic resonance pen sensor with a copper-etched metal mesh pattern, an inspection algorithm and method for measuring the antenna impedance inside the sensor was proposed by measuring only the exposed FPCB connector. The proposed method was configured as a control board consisting of a microprocessor that forms a loop between specific channels according to the command of a computer, a computer-controlled by the Windows program, an LCR meter measuring the impedance between specific channels, and transmitting the measurement results back to the computer. An evaluation of the proposed system and measurements of nine specimens showed that it could detect the defects of the sensor used in the actual product.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2002.11a
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• pp.187-190
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• 2002

The Electrodeless lamp is intended as a high efficacy replacement for the incandescent reflector lamp in many applications. but Increasing awareness of electromagnetic compatibility(EMC) issues in lighting application, the problems of interference generation by electrodeless fluorescent lighting system have been highlighted. In this paper, Maxwell 2D finite element analysis program(Ansoft) is used to obtain electromagnetic properties associated with the coil and nearby structures. and also evaluated Flux B, H by changing the input current.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.11
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• pp.23-29
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• 2008

This paper presents a new conceptual electromagnetic induction eddy current based stainless steel plate spiral type heater for heat exchanger or dual packs heater in hot water system boiler steamer and super heated steamer, which is more suitable and acceptable for new generation consumer power applications. In addition, an active clamping quasi-resonant PWM high frequency inverter using trench gate IGBTs power module can operate under a principle of zero voltage soft commutation with PWM is developed and demonstrated for a high efficient induction heated hot water system and boiler in the consumer power applications. This consumer induction heater power appliance using active clamping soft switching PWM high frequency inverter is evaluated and discussed on the basis of experimental results.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.105-108
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• 2001

In this paper, design procedures of a linear induction motor(LIM) with squirrel cage secondary are presented. The electrical and magnetic loadings are determined by the conventional criteria of the linear induction motors with sheet secondary. Electromagnetic fields of the designed motor are analyzed using finite element method, and characteristics of thrust and currents are presented.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.5
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• pp.305-311
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• 2016

Induction heating is the process in which an electrically conducting object (usually a metal) is heated by electromagnetic induction through heat generated in the object by eddy currents. The main advantage of an induction heating device is the generation of the heat inside the target object itself. Hence, non-contact and safe heating devices are widely used in many industrial and medical fields. Recently, a new dental implant system was developed using a shape-memory alloy, wherein an artificial tooth could be easily removed from the dental implant by heating. This paper discusses the development of an induction-heating device to remove the dental crown in the new implant system. First, the finite element simulation of electromagnetic and thermal coupling analysis was implemented to obtain the temperature distributions of the target object for various frequencies, input currents, and coil shapes. Based on the simulation results, experiments were conducted by using prototypes, and an induction heating device was developed to remove the dental crown from the implant.

• Journal of Aerospace System Engineering
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• v.12 no.5
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• pp.1-7
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• 2018

In this study, we proposed a high frequency induction hardening analysis method based on electromagnetic-thermal co-simulation. In the high frequency induction heating analysis, the results of the finite element analysis (FEA) (considering the change of the material property and the cooling factor according to the temperature) and those of the high frequency induction hardening experiment (using the S45C specimen) were compared. The hardness of the S45C specimens was measured using the micro Vickers hardness test to determine the depth of hardening. The measurement results were then compared with the results of FEA. The result of high frequency induction heating analysis showed that the temperature was more than $750^{\circ}C$, which is the A2 transformation point of S45C, while the temperature during quenching was below $200^{\circ}C$. The results showed that the difference of the depth of hardening between the FEA and the experiment is 0.2mm.