DSpace Repository :: Browsing by Author "WU, PY"

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ALTERNATING MATRICES

(1993-02-01)

WU, PY

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交大名義發表

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應用數學系

;

National Chiao Tung University

;

Department of Applied Mathematics

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AN LP-NORM INEQUALITY

(1983)

WU, PY

;

應用數學系

;

Department of Applied Mathematics

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APPROXIMATE DECOMPOSITIONS OF CERTAIN CONTRACTIONS

(1982)

WU, PY

;

交大名義發表

;

應用數學系

;

National Chiao Tung University

;

Department of Applied Mathematics

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APPROXIMATION BY INVERTIBLE AND NONINVERTIBLE OPERATORS

(1989-03-01)

WU, PY

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交大名義發表

;

應用數學系

;

National Chiao Tung University

;

Department of Applied Mathematics

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C-11 CONTRACTIONS ARE REFLEXIVE

(1979)

WU, PY

;

交大名義發表

;

應用數學系

;

National Chiao Tung University

;

Department of Applied Mathematics

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C-11 CONTRACTIONS ARE REFLEXIVE .2.

(1981)

WU, PY

;

應用數學系

;

Department of Applied Mathematics

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C.0 CONTRACTIONS - CYCLIC VECTORS, COMMUTANTS AND JORDAN MODELS

(1981)

WU, PY

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交大名義發表

;

應用數學系

;

National Chiao Tung University

;

Department of Applied Mathematics

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COMMUTANTS OF CO (N) CONTRACTIONS

(1976-01-01)

WU, PY

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交大名義發表

;

National Chiao Tung University

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COMMUTANTS OF CO CONTRACTIONS - PRELIMINARY-REPORT

(1976-01-01)

WU, PY

;

交大名義發表

;

National Chiao Tung University

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COMMUTANTS OF CO(N) CONTRACTIONS - PRELIMINARY REPORT

(1975-01-01)

WU, PY

;

交大名義發表

;

National Chiao Tung University

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CONDITIONS FOR COMPLETELY NON-UNITARY CONTRACTIONS TO BE SPECTRAL

(1979)

WU, PY

;

交大名義發表

;

應用數學系

;

National Chiao Tung University

;

Department of Applied Mathematics

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CONTRACTIONS SATISFYING ALG T = [T]'

(1977)

WU, PY

;

交大名義發表

;

應用數學系

;

National Chiao Tung University

;

Department of Applied Mathematics

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CONTRACTIONS SATISFYING ALG T=(T)' - PRELIMINARY-REPORT

(1976-01-01)

WU, PY

;

交大名義發表

;

National Chiao Tung University

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CONVEX COMBINATIONS OF PROJECTIONS

(1990-07-01)

CHOI, MD

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WU, PY

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應用數學系

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Department of Applied Mathematics

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DIFFERENCE AND SIMILARITY MODELS OF 2 IDEMPOTENT OPERATORS

(1994-09-01)

WANG, JH

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WU, PY

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應用數學系

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Department of Applied Mathematics

In a recent work, Hartwig and Putcha obtained a complete characterization of those finite matrices which can be expressed as the difference of two idempotents. Extending this result to operators on a possibly infinite-dimensional Hilbert space seems more difficult. In this paper, we initiate its study and obtain, among other things, (1) that not every nilpotent operator is the difference of two idempotents, (2) that if T is the difference of two idempotents, then the spectra of T and -T differ at most by the two points +/-1, and (3) a characterization of differences of two idempotents among normal operators. In the second part of the paper, we develop some similarity-invariant models of two idempotents. These are analogous to the known unitary-equivalence-invariant models for two orthogonal projections.

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FACTORIZATION OF MATRICES INTO PARTIAL ISOMETRIES

(1989-02-01)

KUO, KH

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WU, PY

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應用數學系

;

Department of Applied Mathematics

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HYPERINVARIANT SUBSPACE LATTICE OF A CONTRACTION OF CLASS C.0

(1978)

WU, PY

;

交大名義發表

;

應用數學系

;

National Chiao Tung University

;

Department of Applied Mathematics

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HYPERINVARIANT SUBSPACES OF C-11 CONTRACTIONS

(1979)

WU, PY

;

交大名義發表

;

應用數學系

;

National Chiao Tung University

;

Department of Applied Mathematics

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HYPERINVARIANT SUBSPACES OF C-11 CONTRACTIONS, .2.

(1978)

WU, PY

;

交大名義發表

;

National Chiao Tung University

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HYPERINVARIANT SUBSPACES OF DIRECT SUM OF CERTAIN CONTRACTIONS

(1978)

WU, PY

;

交大名義發表

;

National Chiao Tung University