منابع مشابه
Biorthogonal Wavelets of Maximum Coding Gain through Pseudoframes for Subspaces
A method for designing a signal-adapted, two-channel biorthogonal wavelet filter bank that maximizes coding gain is presented using the technique of Pseudoframes for Subspaces (PFFS). At the same time the PFFS model is able to incorporate the requirements of regularity and perfect reconstruction into this design. The coding gain achieved for AR(2) signals can result in a reduction in bit rate o...
متن کاملParametric Optimization of Biorthogonal Wavelets and Filterbanks via Pseudoframes for Subspaces
We present constructions of biorthogonal wavelets and associated filter banks with optimality using pseudoframes for subspaces (PFFS). PFFS extends the theory of frames in that pseudoframe sequences need not reside within the subspace of interest. In particular, when PFFS is applied to biorthogonal wavelets the underlying flexibility presents opportunities to incorporate optimality, regularity ...
متن کاملCovering of subspaces by subspaces
Lower and upper bounds on the size of a covering of subspaces in the Grassmann graph Gq(n, r) by subspaces from the Grassmann graph Gq(n, k), k ≥ r , are discussed. The problem is of interest from four points of view: coding theory, combinatorial designs, q-analogs, and projective geometry. In particular we examine coverings based on lifted maximum rank distance codes, combined with spreads and...
متن کاملHyperinvariant subspaces and quasinilpotent operators
For a bounded linear operator on Hilbert space we define a sequence of the so-called weakly extremal vectors. We study the properties of weakly extremal vectors and show that the orthogonality equation is valid for weakly extremal vectors. Also we show that any quasinilpotent operator $T$ has an hypernoncyclic vector, and so $T$ has a nontrivial hyperinvariant subspace.
متن کاملApproximating weak Chebyshev subspaces by Chebyshev subspaces
We examine to what extent finite-dimensional spaces defined on locally compact subsets of the line and possessing various weak Chebyshev properties (involving sign changes, zeros, alternation of best approximations, and peak points) can be uniformly approximated by a sequence of spaces having related properties. r 2003 Elsevier Science (USA). All rights reserved.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Michigan Mathematical Journal
سال: 1996
ISSN: 0026-2285
DOI: 10.1307/mmj/1029005391