• 전기학회논문지
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• 제67권3호
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• pp.467-473
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• 2018

R-Bar(Overhead Rigid Conductor system) is being developed for the high-speed in Europe because it has an advantage of cross section area reduction of tunnel compared with OCS (Overhead Catenary Line). Because there are lots of underground sections and mountains in korea, it is necessary to develop the R-Bar for a high-speed line. In this study, a method on speed-up of transition section between OCS and R-Bar is proposed. The commercial program, DAFUL, is used to predict a dynamic characteristics between Overhead Line and pantograph. The program is evaluated according to EN 50318 which is the European Norm for evaluation of the program. Using the evaluated modeling and method, a method for the max. speed of 250 km/h of transition section is proposed.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2015년도 추계학술대회
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• pp.854-857
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• 2015

반도체 기술의 발전으로 시스템-온-칩(SoC : System-on-Chip) 내에 집적되는 소자의 수가 기하급수적으로 증가함에 따라 에너지 감소 기술은 매우 중요한 과제가 되었다. 다양한 저전력 기술 중에서도 동적 전압 주파수 스케일링(Dynamic Voltage and Frequency Scaling)은 가장 대표적인 저전력 기술 중 하나이다. 올바른 DVFS의 구현을 위해서는 복잡한 DC-DC 변환기와 PLL이 필요로 하게 되며, 이런 특성을 정확하게 이해하고 그로 인해 발생하는 오버헤드(overhead)를 반드시 고려해야 한다. 본 논문에서는 MPSoC에서 변환 오버헤드를 최소화하는 전압 선택 알고리즘을 제안한다. 실험을 통해 제안하는 방법은 성능을 유지한 채 에너지 소모 및 변환 오버헤드 감소를 보여준다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.213-214
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• 2006

To reduce the feedback overhead of predicted CSI (channel status information) of adaptive OFDM (orthogonal frequency division multiplexing), we use partial data of CSI and employ linear interpolation. Simulation results show estimated CSI and its MSE.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송∙미디어공학회 2019년도 추계학술대회
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• pp.188-190
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• 2019

Long-term global motion compensation (LT-GMC) was designed to compensate camera motion effectively. The LT-GMC warps a reference picture according to an estimated affine/homography model and stores it in its decoded picture buffer for long-term reference. Most previous works on LT-GMC have focused on improving quality of the warped picture, however, there has been only little consideration on the overhead of its motion coding. In this paper, we address this problem and propose a method, namely Scaling Predictor, to reduce the motion coding overhead for LT-GMC. Our experiment has shown BD-Rate reduction of 1.40% over conventional LT-GMC scheme by applying the proposed method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 A
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• pp.232-235
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• 2000

Design and experiments of a nondestructive system to inspect deterioration of ACSR-OC (ACSR Outdoor Cross-linked Polyethylene Insulated Wire usually used in HV overhead distribution lines presented in this paper. ACSR-OC conductor built to pollutants air for a long period would be easily progress to corrode so that it may lead to the reduction of the effective cross section area of conductors. A fault diagnosis system consisting of a solenoid sensor, a constant current source with RF frequency signal processing unit and a motor driver/controller designed and implemented. This instrument can dot the sensor output variation due to deterioration corrosion, continuously. As a result, it was shown such corrosion detector can readily be utilized estimating the diameter change due to deterioration overhead distribution lines and in giving an warning or inform before severe aged conductor lead to fail.

• 한국철도학회논문집
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• 제9권5호
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• pp.582-587
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• 2006

Since Kyung-Bu High Speed Line has been introduced, a railway electrification has been proceeded rapidly. Therefore, in this study, a specification and application standard for an overhead catenary supporting thin walled steel pole using STKT590 material are proposed in order to improve an economical efficiency. To decide the specification, strength analysis, deflection analysis, deflection test and fracture test are performed. If the supporting structures using high strength materials such as STKT590 are installed, the advantages of cost by the materials price reduction and demand and supply are expected.

• ETRI Journal
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• 제32권4호
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• pp.622-625
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• 2010

In this letter, we assess the scalability of a path computation flooding (PCF) approach to compute optimal end-to-end inter-domain paths in a path computation element-based multi-domain network. PCF yields a drastically reduced network blocking probability compared to a blind per-domain path computation but introduces significant network control overhead and path computation complexity. In view of this, we introduce and compare an alternative low overhead PCF (LoPCF) solution. From the obtained results, LoPCF leads to similar blocking probabilities to PCF while exhibiting around 50% path computation complexity and network control overhead reduction.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부A
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• pp.245-247
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• 1998

Compacting of Overhead power transmission lines can be helpful in solving many problems, such as reduction of land and forest losses. decrease of the line's environmental impact zones, improvement of its electrical performance. And in overhead transmission lines, regular polygon configuration of bundled conductors are considered and adopted. This papers are compared to subconductor surface charges and electric field gradients, line parameters, natural capacities for regular polygon and modified configurations in 345kV 4 bundle 2 circuits horizontal type transmission lines.

• 대한전자공학회논문지SD
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• 제41권11호
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• pp.87-95
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• 2004

본 논문에서는 SoC 테스트를 위한 새로운 테스트 데이터 압축 방법을 제안한다. 제안하는 압축 방법은 테스트 데이터 압축을 위해 압축율과 하드웨어 오버헤드를 고려하여 최대 효율을 가지도록 하는데 기초하고 있다. 압축율을 높이기 위해서 본 논문에서는 IR 기법과 MSCIR 압축 코드를 사용하며, 뿐만아니라 이를 위한 사전 작업인 새로운 맵핑 기법 및 테스트 패턴순서 재조합 방법을 제안한다. 기존의 연구와는 달리 CSR 구조를 사용하지 않고 원래의 테스트 데이터를 사용하여 압축하는 방법을 사용한다. 이렇게 함으로써 제안하는 압축 방법은 기존의 연구에 비해 훨씬 높은 압축율을 가지며 낮은 하드웨어 오버헤드의 디컴프레션 구조를 가진다. ISCAS '89 벤치 회로에 대한 기존의 연구와의 비교로서 그 결과를 알 수 있다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.21-22
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• 2006

In this paper, to improve OFDM PAPR reduction performance of the conventional SLM method, we propose an effective SLM-PRSC hybrid scheme based on the repeated utilization of identical PRSC sequences in time domain. In the proposed scheme, after performing the SLM for the frequency domain OFDM symbol excluding the pre-determined PRSC positions, the final SLM-PRSC hybrid sequence with the lowest PAPR, which is generated by adding the time domain PRSC sequence to the results of the SLM is selected as the transmitted OFDM symbol. In particular, since the identical PRSC sequences generated a priori are repeatedly used for every OFDM symbol, excessive IFFT calculations are avoided. Moreover, the selected PRSC symbols in the frequency domain may be utilized as an overhead information for the SLM. Simulation results reveal that the proposed SLM-PRSC hybrid scheme can remarkably improve the PAPR reduction performance of the conventional SLM, while avoiding excessive increase of IFFT and PAPR calculations and the overhead for the SLM.