• 제목/요약/키워드: 김달수

검색결과 29건 처리시간 0.024초

적응 보상기를 채용한 적응 순환 방향제거기 (An adaptive IIR echo canceller with adaptive compensator)

  • 최삼길;김달수
    • 한국통신학회논문지
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    • 제21권4호
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    • pp.876-883
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    • 1996
  • Adaptive FIR filters are widely used in the echo canceller. But, most of practical systems have the transfer function composed of poles and zeros. In that case, adaptive IIR filters may be more efficient rather than FIR fiters. In this paper, a recently developed C-HARF algorithm is used to implement an adaptive IIR echo canceller. The proposed convergence of the algorithm make it attractive for this application. Extensive computer simulations show that C-HARF algorithm performs better than the NLMS algorithm after convergence, although C-HARF algorithm converges more slowly.

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최소자승법을 이용한 Constrained Multichannel FIR 적응 빔 형성 알고리즘 (Constrained Multichannel Adaptive FIR Beamforming Algorithm Based upon Least Squares Method)

  • 김달수;신윤기;박의열
    • 전자공학회논문지A
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    • 제28A권9호
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    • pp.671-679
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    • 1991
  • In adaptive antenna, several models are known according to a prior knowledge about jammer signal. Among those, Frost model with contraint is generally used however it has the problem that convergence speed is slow and that stability is not good. To improve such problems, this paper proposes constrained NLMS algorithm using LS method. In addition, the result obtained by applying this algorithm to Duvall antenna model is compared with that of Frost model.

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허혈성뇌졸중의 수술치료시 동반되는 합병증과 관리 (Surgical Complication and Its Management in Ischemic Stroke)

  • 김달수;유도성;허필우;조경석;강준기
    • Journal of Korean Neurosurgical Society
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    • 제29권8호
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    • pp.1107-1112
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    • 2000
  • Recently various operative procedures including microsurgery or endovascular surgery have been increasing for the management of ischemic cerebrovascular diseases. Carotid endarterectomy(CEA), extracranial-intracranial(EC-IC) arterial bypass, embolectomy, decompressive craniectomy, arterial transposition, intravascular thrombolysis, and percutaneous transarterial angioplasty and stenting (PTAS) are available surgical modalities for ischemic stroke. This article focuses the complications and perioperative management of patients treated with CEA and carotid PTAS among various surgical managements for ischemic stroke.

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출력오차방법의 다채널 IIR 적응 빔 형성 알고리즘 (Multichannel Adaptive IIR Beamforming Algorithm of Output Error Method)

  • 김달수;박의열
    • 한국통신학회논문지
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    • 제18권4호
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    • pp.530-536
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    • 1993
  • 적응안테나에서는 최근 Gooch에 의하여 방정식 오차 방법을 이용한 새로운 적응 시스템이 제시 되었다. 그러나 이 방법에서는 pole부에 대한 역모델이 필히 요구되며 이로 인하여 안정성을 보장 받지 못한다. 본 논문에서는 Popov의 초안정성 이론을 바탕으로 새로운 알고리즘을 제안하였다. 또한 출력오차방법의 적응 시스템도 개발하였다. 제안한 알고리즘을 출력오차방법의 시스템에 적응하여 Gooch의 결과와 비교 검토하였다.

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LPCVD 질화막 만을 이용한 새로운 LOCOS 공정에 관한 연구 (Study of a New LOCOS Process Using Only Thin LPCVD Nitride)

  • 김지범;오기영;김달수;주승기;최민성
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
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    • pp.429-432
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    • 1987
  • A new LOCOS (Local Oxidation of Silicon) process using a thin nitride film directly deposited on the silicon substrate by LPCVD has been developed in order to reduce the bird's beak length. SEM studies showed that nitride thickness of 50nm can decrease the bird's beak length down to 0.2um with 450nm field oxide. No crystalline defects are observed around the bird's beak after the Wright etch. A 30% improvement in current density was obtained when this new method was applied to MOS transistors (W/L*2.9/20.4) compared to conventional LOCOS process (bird's beak length=0.7um). Other various electrical parameters improved by this new simple LOCOS process are reported in this paper.

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