• The Transactions of the Korean Institute of Power Electronics
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• v.2 no.4
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• pp.28-35
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• 1997

본 논문에서는 송전선로에 직렬로 삽입되어 선로의 리액턴스를 동적으로 보상하는 인버터식 직렬보상기에 대한 동적 응동 해석을 기술하고 있다. 이 직렬보상기는 다중펄스로 동작하는 전압원인버터와 결합변압기, 그리고 제어장치로 구성되어 있으며, 점호각을 조절하여 선로의 리액턴스를 가변하고 용량성 뿐만 아니라 유도성 보상도 가능하다. 이 보상기로 선로의 리액턴스를 감소시키면 전송 유효전력의 증각가 가능한데, 이러한 효과를 본 논문에서는 단일기-무한대-버스 전력계통에 대해 EMTP를 이용한 시뮬레션으로 확인하였으며, 또한 축소모형 제작과 실험을 통해 실험적으로 확인하였다.

• Journal of Advanced Navigation Technology
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• v.12 no.4
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• pp.311-316
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• 2008

A configuration scheme of optical link effectively compensating chromatic dispersion and nonlinear effects accumulated in optical link with single mode fibers (SMFs) is proposed. The proposed optical link configuration consist of optical phase conjugator (OPC) placed at middle of total transmission length and inline dispersion management (DM) as a role of compensating cumulated in each optical repeater of SMF by dispersion compensating fiber (DCF). Net residual dispersion (NRD) of this optical link is designed to be controlled through precompensation and postcompensating. The precompensation and postcompensation are designed to be determined by DCF after transmitter and before receiver, respectively. It is confirmed that optical link configuration with symmetric dispersion map with respect to OPC, which is implemented by controlling NRD through both precompensation and postcompensation, is better to be effective and adaptive than other configuration with NRD controlled by only precompensation or postcompensation.

• Journal of Institute of Control, Robotics and Systems
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• v.3 no.2
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• pp.149-155
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• 1997

본 논문에서는 비선형 시변 시스템을 제어할 경우 제어시스템의 안정성을 보장하고 성능을 향상시키기 위한 새로운 적응제어 구조를 전개하였다. 주어진 플랜트가 선형 시불변이라는 가정하에 표준 기준 모델 적응제어기가 적용될 경우 발생되는 출력오차는 플랜트의 비선형 시변특성으로 인하여 점근적으로 0에 수렴되지 않는다. 이때 미지의 출력오차를 점근적으로 0에 수렴시키는 방법으로 퍼지보상기를 사용하였으며 결과적으로 플랜트의 비선형 시변 특성을 보상하는 효과를 얻을 수 있었다. 퍼지 보상기로는 출력오차등의 조건에 따라 이득이 변하는 퍼지 PID 보상기를 도입하여 안정하게 설계되도록 노력하였다. 또한 출력오차를 점근적으로 0에 수렴시키는 것은 표준 기준 모델 적응제어기 내부의 모든 파라미터와 신호가 유한하게 됨을 의미하기 때문에, 제어시스템 전체의 안정도를 보장할 뿐만 아니라 결과적으로 과도응답 성능을 향상시킬 수 있게 되었다. 몇가지 예제를 대상으로 시뮬레이션을 수행하고 그 결과를 분석함으로써 비선형 시변 시스템을 제어할 경우 본 논문에서 전개된 새로운 적응제어 구조의 타당성을 확인하였다.

• Journal of Advanced Navigation Technology
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• v.25 no.4
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• pp.286-292
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• 2021

Dispersion maps of antipodal symmetric type for improvement of compensation effect in dispersion managed link combined with optical phase conjugation, which can compensate for the distorted wavelength division multiplexed (WDM) signals due to chromatic dispersion and nonlinear Kerr effects of single-mode fiber, were proposed. It was confirmed that the proposed all of antipodal symmetric dispersion maps was more effective to compensate for the distorted WDM channels than the conventional link of uniform type dispersion map. Especially, dispersion maps formed like the inversion of alphabet S were more advantageous as the distorted WDM channels were compensated than dispersion maps formed like alphabet S. It was expected that the variety of optical network topology was more expanded by applying the proposed antipodal symmetric dispersion maps into transmission link.

• Management & Information Systems Review
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• v.35 no.1
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• pp.173-188
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• 2016

The introduction and operation of compensation committee can affect managers' incentive-compensation system. In this context, The purpose of this paper examines whether managers' pay-performance sensitivity is affected by the quality of the compensation committee(compensation committee size, the proportion of outside directors on the compensation committee, the proportion of directors with 2 or more non additional board seats on the compensation committee) To test this hypothesis, we use a sample of 260 firm-year observations between 2001-2013. The results are as follows. Firstly, we find that no significant relevance between the compensation committee size and pay-performance sensitivity. But the proportion of outside directors on the compensation committee and the proportion of directors with 2 or more non additional board seats on the compensation committee is positively associated with both pay-earnings based performance sensitivity and pay-stock based performance sensitivity. Secondly, we find that the integration quality of the compensation committee is positively associated with both pay-earnings based performance sensitivity and pay-stock based performance sensitivity. Overall, our analysis suggests that compensation committee are important mechanism in the design of efficient incentive-compensation system.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.1
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• pp.131-141
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• 2007

This paper proposes analysis on new equipment for power quality in electric railway. The proposed equipment consists of series inverter and parallel inverter. Each inverter is connected by capacitor as dc link. This structure can be compensated for active and reactive power in catenary through transformer. We verified the proposed equipment using the PSCAD/EMTDC and the calculation results from the proposed approach are widely described in the paper.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.49 no.1
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• pp.47-52
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• 2012

A power amplifier is one of important factors for basestation's efficiency and the researches for efficency enhancement focus Doherty amplifier structure with GaN power devices in these days. A memory effect of Doherty amplifier affect operation characteristics for linearity and efficiency. This paper reports on electrothermal nonlinearity modeling and compensation for GaN Doherty amplifier's distortion. Also this paper reports on the dynamic expression of the instantaneous junction temperature as a function of the instantaneous dissipated power. We design distortion model for GaN Doherty amplifier and predistortion compensator for electrothermal memory effect from the proposed behavior model parameters. The simulations was evaluated by ADS Tools and GaN Doherty amplifier with 37dBm. The GaN Doherty amplifier with compensator enhanced about 16dB than without electrothemal memory effect compensator in 2-tone output spectrum.

• The Journal of the Korea Contents Association
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• v.18 no.3
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• pp.409-420
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• 2018

The decision to actively reveal oneself as a consumer on social media depends on whether the focus is more on positive rewards than negative threats associated with self-presentation, that is, who the other party is in that relationship. The audience of self-presentation could also be divided into expressive and instrumental ties: work partners can be classified as an audience of instrumental ties, whereas school friends can be regarded as an audience of expressive ties. This study accordingly predicted that people would focus more on prevention of negative threats than positive reward, exhibiting defensive self-presentation in relationships with strong instrumental ties because the fallout from negative threats due to failed self-presentation have a more detrimental effect than a positive reward from successful self-presentation. The empirical findings thereby indicated that as the proportion of coworkers increased among Facebook friends, the mediation effect through defensive self-presentation increased, whereas such effect through acquisitive self-presentation decreased.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.1
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• pp.21-30
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• 2012

When two bands have different look angle in a space-borne camera system, the registration between two bands is required. The registration cannot be modeled with constant parameters because of dynamic of platform and parallax effect. The parallax effect is caused by terrain relief, hence it causes local distortion between two bands. Therefore, the terrain relief correction in order to reduce the parallax effect is required for better registration result, especially for high resolution image data. Such terrain relief correction also can be applied to image data acquired from multiple detectors with different look angle within a band, which is a one of commonly used configuration for a wider swath in space-borne camera system, in order to reduce the distortion between detectors. The RFM is a popular abstract model in remote sensing field, which gives us the relationship between the image plane and geodetic coordinate system. Therefore, we propose a terrain relief correction method based on the RFM. The experiment showed very promising result.

• Journal of The Korean Association For Science Education
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• v.22 no.3
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• pp.604-616
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• 2002

The purpose of this study was to analyze the development of the compensational thinking by the compensation activities of 'Thinking Science' program. The 138 students were sampled in elementary schools and were divided into two groups, the experimental group of 74 students and the control group of 64 students. Both the compensation activities of the 'Thinking Science' program and a regular science curriculum were implemented to the experimental group, while only a regular science curriculum to the control group. Both experimental and control group were pre-tested with Science Reasoning Task II and compensational thinking test I and were post-tested with compensational thinking test II. This study revealed that the types of strategies used in compensation problem solving were categorized as illogical explanation, rule automation, proportionality, explanation in qualitative terms, additive quantification, inverse proportionality and were related to the context of the items. It was found that compensation activities of the 'Thinking Science' program were effective on the development of the compensational thinking.