• Proceedings of the Optical Society of Korea Conference
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• 2003.07a
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• pp.260-261
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• 2003

위상 부호 다중화 시스템에서 cross talk 잡음은 기준빔 성분들간의 180$^{\circ}$와 다른 위상 천이 오차, 기준빔 성분들의 Bragg 격자로부터 불균일한 회절 세기들, 혹은 non-Bragg-matched 격자로부터 회절 때문에 발생하는 것으로 알려져 있다. 본 논문에서는 cross talk의 다른 원인들이 최소화된 시스템에서 위상 천이 오차만이 존재할 때 이전 연구들과 달리 유한한 contrast ratio를 갖는 이진 랜덤 이차원 이미지들을 광굴절 결정체에 위상 부호 다중화하고 복원할 때 얻어지는 신호대 잡음비(SNR)을 계산하고 이를 실험 측정 결과와 비교한다. (중략)

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.3
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• pp.587-592
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• 2018

An adaptive beam forming system using a phased array antenna improves communication quality by beam forming adaptively to a communication environment having an interference signal. For adaptive beam forming, a good combination of the phases of the excited signals to each radiating element of the phased array antenna should be calculated. In this paper, improved particle swarm optimization algorithm that adds a re-spreading procedure according to particle density was proposed to increase the probability of good phase shift combination output.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.4
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• pp.580-586
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• 2006

This paper proposes high frequency inverter for induction heating and discusses output control of high frequency inverter. Output control method of inverter is controlled by phase shift of switching devices applied to driving signal and the principle and a characteristic estimates of proposed circuit described on normal parameters. Also output characteristics for circuit design presented to numeric analysis and experimental equipment is made to compare theoretical result with an experimental result and an established characteristic estimate.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.973-976
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• 2009

Digital signal processing technique use to variety fields including communication. For these signal processing, FIR digital filter is representative. And for FIR digital filter designing, the window function is used to reduce the Gibbs phenomenon which occurs in the coefficient cutting process of the ideal filter. Therefore, in this paper to improve performance of digital filter, a high-order window function was applied. In this simulation, we compared a peak side-lobe and a transient characteristics with the existing window function.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.6
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• pp.628-630
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• 2016

Compressive sensing can recover an original sparse signal from a few measurements. Its performance is affected by the number of non-zero elements in the signal. The knowledge of partial locations of non-zero elements can improve the recovery performance. In this paper, we apply the partial location knowledge to the multipath matching pursuit. The numerical results show it improves the signal recovery performance and the channel estimation performance in the ITU-VB channel.

• Proceedings of the KOR-KST Conference
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• 2007.11a
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• pp.457-466
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• 2007

• The monthly packaging world
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• s.156
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• pp.182-187
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• 2006

우크라이나,골판지 틈새 시장 유망/러시아, 수입물품 약 80% 모스크바 통해 유통/싱가포르,아시아 RFID 허브 육성/중,홍콩달러 7억5천만 투자/일,제지 업체 작년 경영실적 악화/영,FSA 식품 교통신호 시스템 권장/

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.707-708
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• 2006

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1987.04a
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• pp.206-211
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• 1987

본 논문에서는 입력 신호인 정현파의 위상을 PGZC(positive going zero corssing)에 대해 한주기당 2회씩 추적하도록 하는 디지털 위상도기 회로(DPLL)을 제시한다. 제시된 루루프는 한 주기당 2번의 표본화를 갖도록 함으로써 한 주기당 하나의 표본을 취하는 기존의 DPLLqhek 정상 상태에서의 위상오차 변동범위가 전체적으로 1/2로 감소되었고, 연속 표본들간의 오차와 양자화 준위의 선택에 따라서 루우프의 천이 응답이 좋아짐을 알 수 있었다. 그 해석적 결과를 실제적으로 요구되는 조건류에 대하여 컴퓨터 시뮬레이션을 행함으로써 검증하였다.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2006.07a
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• pp.390-390
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• 2006