• 제목/요약/키워드: Subspace

검색결과 721건 처리시간 0.068초

비 대각요소를 이용한 부공간에서의 적응 빔 형성 기법 (Subspace-Based Adaptive Beamforming with Off-Diagonal Elements)

  • 최양호;엄재혁
    • 한국통신학회논문지
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    • 제29권1A호
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    • pp.84-92
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    • 2004
  • 공분산 행렬의 고유구조에 기초한 뎀 형성 방법은 수렴속도가 빠르고 도래각 추정 오차에 둔감한 이점을 가지고 있다 그러나 Sl (signal Plus interference) 부공간에 대한 기저(basis)를 추정하기 위해 표본 행렬을 고유분해 하는 것을 필요로 하여 그 계산이 매우 복잡하다. 본 논문에서는 표본행렬의 비 대각 요소를 이용하여 턱 공간을 추정하는 간단한 빔 형성 기법을 제안한다. 제안한 방법에서는 중첩된 부어레이들의 빔을 결합하여 최종 적응 출력을 얻는다. 이와 같이 부어레이를 결합하면 하나의 부어레이를 이용하는 경우에 비해 SINR (signal-to-interference-plus-noise ratio) 성능을 증가시킬 수 있다. 고유분해에 의한 방법은 원가는 신호의 도래각, 신호 수 모두에 오차가 있으면 심하게 성능이 저하되지만, 비 대각방법에서는 효율적인 도래각 추정기법을 적용하여 이러한 오차에 매우 둔감하다.

ON INTUITIONISTIC FUZZY SUBSPACES

  • Ramadan, Ahmed Abd El-Kader;El-Latif, Ahmed Aref Abd
    • 대한수학회논문집
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    • 제24권3호
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    • pp.433-450
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    • 2009
  • We introduce a new concept of intuitionistic fuzzy topological subspace, which coincides with the usual concept of intuitionistic fuzzy topological subspace due to Samanta and Mondal [18] in the case that $\mu=X_A$ for A $\subseteq$ X. Also, we introduce and study some concepts such as continuity, separation axioms, compactness and connectedness in this sense.

Investigating SIR, DOC and SAVE for the Polychotomous Response

  • Lee, Hak-Bae;Lee, Hee-Min
    • Communications for Statistical Applications and Methods
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    • 제19권3호
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    • pp.501-506
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    • 2012
  • This paper investigates the central subspace related with SIR, DOC and SAVE when the response has more than two values. The subspaces constructed by SIR, DOC and SAVE are investigated and compared. The SAVE paradigm is the most comprehensive. In addition, the SAVE coincides with the central subspace when the conditional distribution of predictors given the response is normally distributed.

시변 방위 추정을 위한 Extended PASTd (Projection Approximation Subspace Tracking with Deflation) 알고리즘 (Extended PASTd (Projection Approximation Subspace Tracking with Deflation) Algorithm for time-varying DOA estimation)

  • 임준석;이종명
    • 한국음향학회:학술대회논문집
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    • 한국음향학회 2000년도 하계학술발표대회 논문집 제19권 1호
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    • pp.189-192
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    • 2000
  • 본 논문은 Nonstationary 환경에서 동작하는 소나의 DOA추정의 정확도를 높이기 위하여 가변 망각인자를 도입한 새로운 Extended PASTd (Extended Projection Approximation of Subspace Tracking with deflation) 을 제안하고 기존 알고리즘과 비교함으로써 새로운 알고리즘의 향상된 성능을 보인다.

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Subspace projection과 SCORE algorithm을 이용한 두 가지 전파방해 대응기술의 성능비교 (Implementation of Improved Functional Router Using Embedded Linux System)

  • 한상윤;신정환;허준
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2006년도 하계종합학술대회
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    • pp.79-80
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    • 2006
  • In this paper, we compare two different anti-jamming schemes, Subspace projection and SCORE algorithm. For multipath cancelation, nulling technique is applied to both anti-jamming schemes. It is noted that SCORE algorithm is more robust to the multipath interference. It is also noted that Subspace projection scheme requires nulling technique for multipath mitigation.

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구조물의 고유진동수 및 모드형상의 계산을 위한 가속화된 부분공간반복법 (Accelerated Subspace Iteration Method for Computing Natural Frequencies and Mode Shapes of Structures)

  • Kim, Byoung-Wan;Kim, Chun-Ho;Lee, In-Won
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2003년도 가을 학술발표회 논문집
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    • pp.503-508
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    • 2003
  • This paper proposes modified subspace iteration method for efficient frequency analysis of structures. Proposed method uses accelerated Lanczos vectors as starting vectors in order to reduce the number of iterations in the subspace iteration method. Proposed method has better computing efficiency than the conventional method when the number of desired frequencies is relatively small. The efficiency of proposed method is verified through numerical examples.

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A MIXED METHOD OF SUBSPACE ITERATION FOR DIRICHLET EIGENVALUE PROBLEMS

  • Lee, Gyou-Bong;Ha, Sung-Nam;Hong, Bum-Il
    • Journal of applied mathematics & informatics
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    • 제4권1호
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    • pp.243-248
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    • 1997
  • A full multigrid scheme was used in computing some eigenvalues of the Laplace eigenvalues problem with the Dirichlet bound-ary condition. We get a system of algebraic equations with an aid of finite difference method and apply subspace iteration method to the system to compute first some eigenvalues. The result shows that this is very effective in calculating some eigenvalues of this problem.

The Image of Derivations on Banach Algebras of Differential Functions

  • Park, Dal-Won
    • 충청수학회지
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    • 제2권1호
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    • pp.81-90
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    • 1989
  • Let $D:C^n(I){\longrightarrow}M$ be a derivation from the Banach algebra of n times continuously differentiable functions on an interval I into a Banach $C^n(I)$-module M. If D is continuous and D(z) is contained in the k-differential subspace, the image of D is contained in the k-differential subspace. The question of when the image of a derivation is contained in the k-differential subspace is discussed.

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구조물의 고유모드 해석을 위한 가속화된 초기벡터 구성기법 (Accelerated Starting Vectors for Analysis of Natural Modes of Structures)

  • 김병완;정형조;이인원
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 춘계학술대회논문집
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    • pp.784-787
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    • 2004
  • Modified version of subspace iteration method using accelerated starting vectors is proposed to efficiently calculate free vibration modes of structures. Proposed method employs accelerated Lanczos starting vectors that can reduce the number of iterations in the subspace iteration method. Proposed method is more efficient than the conventional method when the number of required modes is relatively small. To verify the efficiency of proposed method, two numerical examples are presented.

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부분 공간법을 이용한 연속 냉간 압연기의 시스템 규명에 관한 연구 (A Study on the System Identification of Cold Tandem Mills using the Subspace Method)

  • 장유신;김인수;이만형
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1995년도 추계학술대회 논문집
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    • pp.299-303
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    • 1995
  • This paper charcterizes dynamics of cold tandem minns, and constructs it state-space model of which are linear time invariant, using subspace method. Step responses particularly show the influence on mass transfer delay. Input-output data set are obtained form nonlinear differential equations including mass transfer delay and nonlinearity. It is shown that the identified state-apace model well approximates the original systems dynamics.

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