• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1841-1843
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• 2001

Asymmetrical parallel coupled lines are used in a number of circuits such as multi-band coupler and combline type band pass filter. Although graphical results and formulas are available for the design of coupled lines, the design procedure is hard to use, because even- and odd- mode impedances are always expressed in terms of the physical geometry. In this paper, we introduce a method to find design parameter using finite element analysis. By employing the capacitance obtained by FE analysis, design parameters for each lines are extracted. To show the validity of extracted design parameter for asymmetrical parallel coupled line, we have designed and simulated a planar type combline band pass filter.

• Journal of Chest Surgery
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• v.26 no.12
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• pp.969-971
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• 1993

The sternal turnover has a limited use in an asymmetrical funnel chest. However we tried `One-half sternal turnover` as a new operative approach for an asymmetrical funnel chest. Through the bilateral submammary skin incision, median sternotomy was made from xiphoid process to midsternum and extended horizontally. The segment of ribs were cut at the angle of depression. The en-bloc resected chest wall segment contained one-half sternum as well as a part of ribs and left half of rectus muscle. After turning over the en-bloc segment, reapproximation with wiring was done. Sternotomy wound was closed in layer after placing of substernal drainage tube. Postoperatively, the chest wall was stable and the recovery course was uneventful except left-sided minimal pneumothorax which was cured spontaneaously. The patient was discharged on postoperative 14th day.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.257-260
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• 2005

Three different current-mode control schemes, peak current-mode control, charge control, and average current-mode control, are investigated for applications to asymmetrical half-bridge dc-to-dc converters. The principles, implementation, and performance of the three control schemes are compared in an attempt to identify the irrespective merits and limitations. Design examples for feedback compensations are given for the three control schemes. A 50 W experimental asymmetrical half-bridge dc-to-dc converter was used to experimentally verify the theoretical results of the paper.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.8
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• pp.368-374
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• 2002

In this paper, we introduce a procedure to obtain a equivalent circuit of comb-line band pass filter. By employing equivalent circuits of each asymmetrical coupled line. we composed the full equivalent circuit of comb-line bandpass filter and derived simple design equations for extracting each line's impedance. To show the validity of design equations, we simulated and fabricated a planar type comb-line bandpass filter, which has center frequency 1.8㎓, band-width 50㎒ and four resonators. The resulting filter is very compact, have broad stop band with the second pass band centered at four times the center frequency of the first pass band. The experimental results show exact performances of design specification.

• Journal of Electrical Engineering and Technology
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• v.12 no.3
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• pp.1235-1244
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• 2017

This paper proposes a fuzzy logic controlled new topology of high voltage gain zero voltage switching (ZVS) asymmetrical PWM full-bridge DC-DC boost converter for constant load and high power applications. The APWM full-bridge stage provides high voltage gain and soft-switching characteristics increase the efficiency and reduce the switching losses. Fuzzy logic controller (FLC) improves the performance and dynamic characteristics of the proposed converter. A comparison with a classical proportional-integral (PI) controller demonstrates the high performances of the proposed technique in terms of effective output voltage regulation under different operating conditions. Simulation is done by integrating two different simulation platforms $PSIM^{(R)}$ and $Matlab^{(R)}/Simulink^{(R)}$ by using SimCoupler tool of $PSIM^{(R)}$. Experimental results using 120W load have been provided to validate the results.

• Journal of Power Electronics
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• v.15 no.1
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• pp.227-234
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• 2015

This paper presents the application of bee colony optimization (BCO) to obtain the optimal switching angles for single phase PWM AC choppers. The optimal switching angles are found in the region of 0-${\pi}$ based on the asymmetrical PWM technique. This PWM process results in improvements of the total harmonic distortion of the output voltage and in the input power factor. Simulation and experimental results are compared with the conventional PWM to verify the performance of the proposed PWM process.

• Archives of Craniofacial Surgery
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• v.20 no.4
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• pp.265-269
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• 2019

Congenital hypoplasia of the depressor anguli oris muscle is a rare cause of asymmetrical crying facies in newborns. The clinical manifestations range from mild to severe asymmetry and may persist up to adulthood. In the current case, the patient did not exhibit other congenital anomalies or paralysis of other branches of the facial nerve. This adult patient presented with severe asymmetrical lower lip deformity during full mouth opening since birth. A chromosomal study for the detection of 22q gene deletion yielded negative results. The electromyography findings of the lower lip were insignificant. Depressor labii inferioris muscle resection was not effective, but bidirectional (horizontal and vertical) fascia lata grafting improved the aesthetic appearance of the asymmetrical lower lip. The patient showed improved lower lip symmetry during full mouth opening at 1 year after the surgery. Therefore, the details of this rare case are reported herein.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.8
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• pp.65-72
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• 1997

An asymmetrical cross-coupled compensator to improve the contouring performance is proposed. This is a refinement of the structure suggested by Koren. The position loop is closed with a proportional controller as in the uncoupled system. An additional input term proportional to the component of the contour error along the corresponding axis is included. The controller gains are chosen to give an appropriate frequency response and an optimum range for the damping ratio. The effectiveness of the proposed controller is studied by means of digital simulations of the dynamics of the drives and the controller for 4 types of command trajectories: straight line contour, cornering contour, circular contour, elliptic contour. Substantial improvement in contouring performance is obtained for a range of contouring conditions.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.3 no.1
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• pp.27-34
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• 2009

Hearing impaired person's hearing loss has personally various shape, so existing symmetrical auditory filter of frequency band method wasn't properly simulated the hearing impaired person's various hearing loss shape. The shapes of auditory filter are asymmetrical different with each center frequency and each input level. Hearing impaired person which has hearing loss was differently changed with that of normal hearing people and it has different value for speech of quality through auditory filter. In this study, the asymmetrical auditory filter was simulated and then some tests to estimate the filter's performance objectively were performed. The experiment as simulated auditory filter's performance evaluation method used perceptual evaluation of speech quality (PESQ) and log likelihood ratio (LLR) for speech through auditory filter. In the test, processed speech was evaluated objective speech quality and distortion using PESQ and LLR value. When hearing loss processed, PESQ and LLR value have big difference between symmetrical and asymmetrical auditory filter. It means that the difference of the shape auditory filter may affect to speech quality. Especially, when hearing loss existed, auditory filter changing according to asymmetrical shape for each center frequency affected to perceive speech quality of the hearing impaired.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.1100-1102
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• 2002

In this paper, resonant characteri-sties of the asymmetrical soft switching half bridge converter is analyzed. The operation principle for proposed converter is explained in steady-state and its operation characteristics by switching frequency is presented with experimental result. Experimental results carried out on a system prototype are included in this paper.