• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.6
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• pp.45-53
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• 1996

In this paper, the convergence behavior of timing phase when an adaptive partial response equalizer and decision-directed type of a PLL work together in a digital recording channel is described. The phenomena of getting biased in timing phase when the convergence parameter of an adaptive partial response equalizer and timing recovery constant of a PLL are not selected properly is introduced. The phenomena, occurring due to perturbation of timing phase, are analyzed, by computer simulation and the region of ocnvergence for timing phase is discussed. Also, a method to overcome the phenomena using a variable step-size parameter is described.

• Korean Journal of Metals and Materials
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• v.50 no.9
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• pp.691-695
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• 2012

Calcium phosphate ceramic composites, consisting of hydroxyapatite(HA) and tricalcium phosphate (TCP), were fabricated by solid state sintering in order to investigate the effect of their initial compositions on microstructural evolutions and biocompatibility. All the sintered calcium phosphate ceramics exhibited almost full densification, while the grain growth of the composites increased with an increasing TCP content in the green body. The TCP phase transformed into a Ca-deficient HA phase during sintering via the diffusion of calcium ions from the HA phase into the TCP phase. The phases formed in the composites significantly affected the biocompatibility of the composites. The HA-matrix ceramic composites with TCP had a better cellular response than the pure HA ceramics, presumably due to the newly formed Ca-deficient HA.

• The Pure and Applied Mathematics
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• v.25 no.4
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• pp.345-355
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• 2018

This paper looks into phase plane behavior of the solution near the positive steady-state for the system with prey density dependent response functions. The positive invariance and boundedness property of the solution to the objective model are proved. The existence result of a positive steady-state and asymptotic analysis near the positive constant equilibrium for the objective system are of interest. The results of phase plane analysis for the system are proved by observing the asymptotic properties of the solutions. Also some numerical analysis results for the behaviors of the solutions in time are provided.

• Korean Journal of Optics and Photonics
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• v.12 no.4
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• pp.327-333
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• 2001

Estimation of the frequency response of Ti:LiNb03 traveling-wave optical modulator with phase reversal electrodes is succinctly presented. The fact that such devices may have bandpass characteristics is demonstrated through simulations based on the derived equations. The influence of each parameter of traveling-wave electrodes on the frequency response is investigated in detail. It is shown that the center frequency and the bandwidth of response curves can be effectively adjustable by changing the MW effective index and the interaction length of the electrodes. rodes.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.422-423
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• 2006

We have studied phase transition time and response time of optically compensated splay(OCS) cell as a function of surface pretilt angle. With decreasing surface pretilt angle, phase transition time decreases and response time becomes faster in the OCS cell. Besides, the more surface pretilt angle decreases, the easier OCS structure is obtained.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1836-1840
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• 2003

This paper, we propose a new phase-locked loop (PLL) system with the controllable output phase, independent from the output frequency, and lock-up time. This PLL system has a dual control loop is described, the inner loop greatly improved VCO characteristic such as faster speed response as well as higher operation bandwidth, to minimize the effect of the VCO noise and the power supply variation and also get better linearity of VCO output. The main loop is the heart of this PLL which greatly improved the output frequency instability due to the external high frequency noise coupling to the input reference frequency also the main loop can control the output phase, independent from the output frequency, and reduce the lock-up time of the step frequency response. The experimental results confirm the validity of the proposed strategy.

• Journal of Electrical Engineering and Technology
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• v.11 no.6
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• pp.1707-1713
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• 2016

This paper proposes a dc error compensation algorithm using dq-synchronous coordinate transform digital phase-locked-loop in single-phase grid-connected converters. The dc errors are caused by analog to digital conversion and grid voltage during measurement. If the dc offset error is included in the phase-locked-loop system, it can cause distortion in the grid angle estimation with phase-locked-loop. Accordingly, recent study has dealt with the integral technique using the synchronous reference frame phase-locked-loop method. However, dynamic response is slow because it requires to monitor one period of grid voltage. In this paper, the dc offset error compensation algorithm of the improved response characteristic is proposed by using the synchronous reference frame phase-locked-loop. The simulation and the experimental results are presented to demonstrate the effectiveness of the proposed dc offset error compensation algorithm.

• The Transactions of the Korean Institute of Power Electronics
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• v.25 no.3
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• pp.235-241
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• 2020

In this paper, we propose the bus/bypass synchronization phase lock loop (B-Sync PLL) method using each phase voltage controller of a parallel UPS inverter. The B-Sync PLL included in each phase voltage control system of parallel UPS inverters has the transient response and the phase synchronization error at grid normal or blackout. The validity of this method is verified by simulation and experiment. As a result, the parallel UPS inverters using the proposed method confirmed that the output phase was continuously synchronized when a grid blackout, improving the transient response characteristics for stable load power supply and equal load sharing.

• Korean Journal of Biological Psychiatry
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• v.20 no.3
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• pp.66-73
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• 2013

Sexual behavior is crucial in life, yet comparatively little is known about the mechanisms in the sexual response in humans. A lot of theories and models have been developed to explain about the process of the sexual response in humans. The first model of sexual function was described by Masters and Johnson, defined the four-phase model (phases of excitation, plateau, orgasm and resolution). Helen Kaplan proposed a slightly different model of human sexual response by adding the conception of the desire phase. Some years later, a new model of circular sexual response pattern was described by Whipple and Brash-McGreer, who acknowledged the cyclic nature of women's sexual response. Basson presented an alternative model of women's normative sexual function, which featured a responsive form of desire in women's sexual response. Bancroft developed a new theoretical model, the Dual Control Model, which postulates sexual response and arousal is ultimately determined by the balance between the sexual activation or excitation system and the sexual inhibition system. The Sexual Tipping Point is a model created by Perelman, suggesting that a sexual response is determined by a balance between excitatory or inhibitory factors that may be psychological, organic, psychosocial, or cultural. A comprehensive understanding of sexual response and function is of paramount importance for the psychiatrist to study sex, offer counseling to the patient on sex, and practice sex therapy. In this literature, models of sexual response would be reviewed to understand the knowledge of the sexual functioning in humans.

• Journal of the Korean Institute of Telematics and Electronics
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• v.23 no.4
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• pp.571-577
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• 1986

In this paper, we have investigated pole-zero shifting due to variable stopband frequency Ws and passband ripple Ap of elliptic function filters. Also we have studied the phase, group-delay, unit step response and impulse response of elliptic filters. We show that in the passband the phase linearity improves as Ws increases, and eventually it approaches that of a chebyshev function filter.