• Journal of electromagnetic engineering and science
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• v.12 no.4
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• pp.240-246
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• 2012

This paper presents a novel modeling technique for traces that cross a defected ground structure. A simple and accurate equivalent circuit model provides clear insight into the coupling mechanism between a microstrip line and a slot or split. The circuit models consist of a transformer as the coupling mechanism and LC resonators as the ground with a slot or split structure. Resistors, capacitors, and inductors are added to the model to increase accuracy and equivalence at high frequency. Simulated and measured S-parameters are presented for defected ground structures. The accuracy and validity of the proposed equivalent circuit model is verified by evaluation of the S-parameter characteristics of the defected ground structures and comparison with measured results.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.317-320
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• 2003

As a convenient means for the characterization of the wall voltage and wall charge of AC PDPs during the sustain period, an equivalent circuit model for AC PDPs is presented. The equivalent circuit model for AC PDPs consists of capacitors and thyristors. The equivalent circuit model is based on the physical structure of the AC PDP and the I-V characteristic of the discharge space. This equivalent circuit model can be easily implemented in the standard simulators such as SPICE and can easily simulate the variation of the current, charge and voltage involved in AC PDPs as the supply voltage varies.

• Journal of KSNVE
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• v.6 no.5
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• pp.645-652
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• 1996

In this paper an identification method is presented to obtain the equivalent electric circuit model of a wideband underwater acoustic piezoelectric vibrator. Unknown parameters involved in the equivalent circuit are indentified using the measured electrical admittances in air. The proposed method is applied to an example transducer. The validity of equivalent circuit model is demonstrated by the comparison between the experimental measurements and analytical calculations of TVR(transmitting voltage response) in water.

• Journal of Power Electronics
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• v.17 no.2
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• pp.561-569
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• 2017

Power converter design requires simulation accuracy. In addition to the requirement of accurate models of power semiconductor devices, this paper highlights the role of considering a very good description of the converter circuit layout for an accurate simulation of its electrical behavior. This paper considers a simple experimental circuit including one switching cell where a MOSFET transistor controls the diode under test. The turn-off transients of the diode are captured, over which the circuit wiring has a major influence. This paper investigates the necessity for accurate modeling of the experimental test circuit wiring and the MOSFET transistor. It shows that a simple wiring inductance as the circuit wiring representation is insufficient. An adequate model and identification of the model parameters are then discussed. Results are validated through experimental and simulation results.

• 한국정보통신설비학회:학술대회논문집
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• 2007.08a
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• pp.27-30
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• 2007

This paper deals with an equivalent circuit model for RF passive components. Rational functions are obtained from the frequency responses of EM simulation by using Foster canonical partial fraction expressions. The Vector Fitting(VF) and the Adaptive Frequency Sampling(AFS) scheme are also implemented to obtain the rational functions. A passivity enforcement algorithm is applied to ensure the stability of the equivalent circuit model. In order to verify the schemes, S parameters of the equivalent circuit model is compared to those of EM simulation in case of the microstrip line structure with 3 slots in ground.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.2
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• pp.99-105
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• 2011

The magnetic circuit analysis excluding flux loss and fringing effect often gives a result with unignorable error, when compared with real system. But, it is not easy to make a complete magnetic circuit model with the loss effects. This paper introduces a relatively simple method to build the model including the flux loss and fringing effect, in which the paths of leaked flux are simplified in terms of circular arcs and straight lines. After modification of the model, the error of about 36 % in maximum between the magnetic circuit analysis and FEM analysis is reduced to about 7 %.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.991-996
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• 2007

Since the performance of the circuit breaker mainly depends on the spring operating mechanism, the analysis of the spring operating mechanism is required. The spring, especially closing spring, stores the deformation energy due to the compression and then accelerates the big loads rapidly in the circuit breaker. To accurately carry out the kinematic and dynamic analysis of the circuit breaker, the precise modeling of the spring behavior is necessary. In this paper, the static stiffness of the spring is captured by using the tester. When the spring is used in the circuit breaker, it is installed horizontally. Therefore, Sine excitation tests are carried out horizontal and vertical direction. Three types of spring models such as a linear spring model, modal spring model, and nodal spring model are suggested and compared with the experimental results.

• Journal of electromagnetic engineering and science
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• v.11 no.2
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• pp.122-127
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• 2011

A general analysis of an aperture-coupled vertically mounted strip antenna is presented to examine its circuit characteristics. Based on the present analysis, an equivalent circuit model is developed, and an analytic or semi-analytic evaluation of the related circuit element values is described. The effects of structure parameters on the antenna characteristics were studied with the developed equivalent circuit, and the design curves were obtained. To check the validity of the proposed analysis and design theory, two C-band antennas (5.0 GHz and 4.5 GHz) were designed and fabricated. Their computed characteristics, derived from the proposed network analysis, were compared with the measurement and simulation results. The error of the current model in predicting the operating center frequency was less than 0.50 %. In addition, the observed bandwidth was found to be comparable to the conventional microstrip antennas. All the results fully validated the efficiency and accuracy of the proposed analysis and network model.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.7
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• pp.1048-1056
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• 2001

Decoupling capacitors are commonly used to reduce the effect of SSN propagated through parallel power and ground planes in high-speed multilayer printed circuit boards (PCBs). In this paper, we introduced a simple high frequency measurement and proposed a wideband (50 MHz ∼3 GHz) equivalent circuit model for decoupling capacitor considering high frequency parasitic effects. The proposed model can be easily combined with the SPICE model of power supply planes far SSN analysis. The circuit simulations with the proposed model show good agreement with the measurement results. Also, we expect to accurately analyze the noise reduction effect as a function of value and location using the proposed model of decoupling capacitor.

• 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.