• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.274-275
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• 2007

The investigation of the equivalent circuit models for the electrode/electrolyte interface has been pursued for a long time by several researchers. Previous circuit models fit the experimental results in limited conditions such as frequency range, type of electrode, or electrolyte. This paper describes a new electrical circuit model and its capability of fitting the experimental results. Electrochemical impedance spectroscopy was used to characterize the interface for Au, Pt, and stainless steel electrode in 0.9% NaCl solution. Both the proposed model and the previous model were applied to fit the measured impedance results for comparison. The proposed model fits the experimental data more accurately than other models especially at the low frequency range, and it enables us to predict the impedance at very low frequency range, including DC, using the proposed model.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.9
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• pp.882-888
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• 2002

This paper proposed a bias stability circuit that compensates the degradation of MMIC's performance for the variation of the process and temperature. The proposed bias circuit proved the superior effect compared with the conventional bias circuit using the constant current source. It designed and fabricated simultaneously two amplifier on one layout for comparison in same conditions. One is amplifier with conventional bias circuit using constant current source and the other is amplifier with proposed bias stability circuit. The chip was measured the microwave performances under process variation that classed the level NOM, MIN and MAX. The amplifier with a conventional bias circuit using constant current source has 6.4 dB gain variation and 7 mA Ids variation at 1.8 GHz, but the amplifier with the proposed bias circuit has the 2.1 dB gain variation and 3 mA Ids variation. As the result, MMIC having the proposed bias circuit shows the superior compensation of the quiescent point than the MMIC having the conventional bias circuit under the variations of the process and temperature and can improve the yield of the MMIC. The fabricated chip size is 1.2 mm $\times$ 1.4 mm.

• Journal of Software Engineering Society
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• v.27 no.1
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• pp.1-7
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• 2018

The consumption of mobile device batteries which are limited resources is an important criterion when circuit designers analyze and evaluate circuits. For this reason, researchers conducted researches with different models of battery consumption to analyze power consumption of mobile devices. The battery consumption model generation techniques have various characteristics depending on availability of sensors, run-time model generation, and models for using in verification and testing. However, there is lack of comparison and analysis between varied battery consumption model generation methods. In this research, we compare and evaluate the analysis methods which have been studied so far to support the circuit investigation for circuit designers. Finally, we suggest the direction of researches in battery consumption analysis using the comparison result.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.592-594
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• 2002

Hybrid stepping motor(HSM) has very small airgap and teeth. These bring out the saturation in the teeth easily. In this paper. the 3 dimension equivalent magnetic circuit network method (EMCNM) based on the trapezoidal element is used for the accurate and efficient nonlinear analysis of HSM. and the validity of the analysis results by the proposed method is verified by comparison with the experimental results.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1885-1891
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• 2010

Recently metropolitan local governments is actively introducing urban railway's expand and light rail transit as a means of new transport system. DC electricity feeder system operating in the domestic urban railway is typically a feedback circuit consisted of the contact wire and electric railway vehicle via rail. But stray current is to be defined as a current flowing on a structure that is not part of the intended electrical circuit with respect to a given structure. Stray current is generally results from the leakage of return currents from large DC traction systems that are grounded or have a bad earth-insulated return path. At the place where the current leaves the rail and metallic structures, electrolytic corrosion may take place. This paper presents comparison analysis of field test methods based on criteria of electrolytic corrosion protection of buried metallic structures adjacent to DC traction systems.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.3
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• pp.305-310
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• 2010

DC electricity feeder system operating in the urban railway is typically a feedback circuit consisted of the contact wire and electric railway vehicle via rail. But stray current is flowed on a structure that is not part of the intended electrical circuit with respect to a given structure. This paper presents comparison analysis of field test cases based on criteria of electrolytic corrosion protection of buried metallic structures adjacent to DC traction systems. As a result of it, we confirmed that measurement methods are different from each other about the same tests. Therefore measurement methods to prevent electrolytic corrosion need to establish electrical facilities standards to be applied domestic.

• Proceedings of the KIPE Conference
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• 2015.07a
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• pp.321-322
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• 2015

The aim of this paper is to propose a design method for the double-sided LCC compensation circuit for 6.6kW electric vehicle (EVs) wireless charger. The analysis and comparison with several compensation topologies such as SS, SP, PS, PP and the hybrid LCC compensation is presented. It has been found that the hybrid LCC compensation has superior performance in comparison with other topologies. The design procedure for the EV charger is presented and the PSIM simulation results are provided.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.515-518
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• 2002

This paper presents the iterative procedure with the concept of expanded waves in the spectral and spatial domains using the fast modal algorithm. We presents its applications to microwave integrated circuits on resistive substrate. The advantage is a reduction in computation time. These calculated results are checked by comparison with the experimental and simulated results by Sonnet and Momentum program.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2002.11a
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• pp.105-109
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• 2002

A TVS and Varistor are preservative equipment against electro static discharge(ESD). We use a TVS for I/O protection of a circuit which has faster response time than a Varistor. And a Varistor has large power capability, therefore, which be used in input stage for internal pressure prevention. This paper will compare a TVS with a Varistor with respect to response characteristic to ESD in DC 24[V] low voltage circuit.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.674-677
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• 2000

Operational principles and driving characteristics of two well-known energy recovery circuits for ac plasma display panels Weber and Sakai circuits are investigated Efficiency of two circuits is analyzed by comparing the in put current of the circuits with different operating conditions. Driving characteristics of the Weber circuit are studied when the magnitude and pulse width of the driving boltage very.