• 제목/요약/키워드: decomposable

검색결과 79건 처리시간 0.026초

CONTINUITY OF LINEAR OPERATOR INTERTWINING WITH DECOMPOSABLE OPERATORS AND PURE HYPONORMAL OPERATORS

  • Park, Sung-Wook;Han, Hyuk;Park, Se Won
    • 충청수학회지
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    • 제16권1호
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    • pp.37-48
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    • 2003

  • In this paper, we show that for a pure hyponormal operator the analytic spectral subspace and the algebraic spectral subspace are coincide. Using this result, we have the following result: Let T be a decomposable operator on a Banach space X and let S be a pure hyponormal operator on a Hilbert space H. Then every linear operator ${\theta}:X{\rightarrow}H$ with $S{\theta}={\theta}T$ is automatically continuous.

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WEAKLY WELL-DECOMPOSABLE OPERATORS AND AUTOMATIC CONTINUITY

  • Cho, Tae-Geun;Han, Hyuk
    • 대한수학회지
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    • 제33권2호
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    • pp.347-365
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    • 1996

  • Let X and Y be Banach spaces and consider a linear operator $\theta : X \to Y$. The basic automatic continuity problem is to derive the continuity of $\theta$ from some prescribed algebraic conditions. For example, if $\theta : X \to Y$ is a linear operator intertwining with $T \in L(X)$ and $S \in L(Y)$, one may look for algebraic conditions on T and S which force $\theta$ to be continuous.

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ALGEBRAIC SPECTRAL SUBSPACES OF GENERALIZED SCALAR OPERATORS

  • Han, Hyuk
    • 대한수학회논문집
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    • 제9권3호
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    • pp.617-627
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    • 1994

  • Algebraic spectral subspaces and admissible operators were introduced by K. B. Laursen and M. M. Neumann in 1988 [L88], [N]. These concepts are useful in automatic continuity problems of intertwining linear operators on Banach spaces. In this paper we characterize the algebraic spectral subspaces of generalized scalar operators. From this characterization we show that generalized scalar operators are admissible. Also we show that doubly power bounded operators are generalized scalar. And using the spectral capacity we show that a generalized scalar operator is decomposable. Then we give an example of an operator which is not admissible but decomposable.

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DWTHE: 분할 기반의 히스토그램 평활화 (DWTHE: Decomposable Weighted and Thresholded Histogram Equalization)

  • 김매리;정민교
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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    • 제15권11호
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    • pp.856-860
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    • 2009

  • 본 논문은 Wang-Ward의 WTHE(Weighted and Thresholded Histogram Equalization) 방법에 히스토그램 분할 개념을 적용한 새로운 영상 화질 개선 방법(DWTHE: Decomposable WTHE)을 제안한다. DWTHE는 먼저 영상의 평균 자기 값 또는 명도 균등 분할점을 기준으로 입력 히스토그램의 영역을 분할하고, 분할된 각 영역의 확률밀도 값을 가중치로 사용하여 새로운 히스토그램을 만든 후, 히스토그램 평활화 과정을 수행하게 된다. 하나의 가중치를 사용하는 WTHE 방법과 다르게, 제안 방법은 히스토그램 분할로 인한 복수외 가중치 값을 사용하게 되며, 실험 결과 제안 방법은 기존 방법에 비해 우수한 화질 개선 효과를 보여주었다.

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