Results 1 to 10 of about 151,365 (138)

Analysis of crystallographic phase retrieval using iterative projection algorithms. [PDF]

Acta Crystallogr D Struct Biol
For protein crystals in which more than two thirds of the volume is occupied by solvent, the featureless nature of the solvent region often generates a constraint that is powerful enough to allow direct phasing of X-ray diffraction data. Practical implementation relies on the use of iterative projection algorithms with good global convergence ...
Barnett MJ, Millane RP, Kingston RL.
europepmc   +4 more sources

A unified evaluation of iterative projection algorithms for phase retrieval [PDF]

, 2006
Iterative projection algorithms are successfully being used as a substitute of lenses to recombine, numerically rather than optically, light scattered by illuminated objects.
Abrahams J. P., Bates R. H. T., Brègman L. M., Buerger M. J., Gerchberg R., Goodman J. W., Marchesini S., Polak E., Polak E., Press W. H., Rossmann M. G., S. Marchesini, Stark H.   +12 more
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Iterative algorithms with seminorm‐induced oblique projections [PDF]

Abstract and Applied Analysis, 2003
A definition of oblique projections onto closed convex sets that use seminorms induced by diagonal matrices which may have zeros on the diagonal is introduced. Existence and uniqueness of such projections are secured via directional affinity of the sets with respect to the diagonal matrices involved. A block‐iterative algorithmic scheme for solving the
Censor, Yair, Elfving, Tommy
openaire   +3 more sources

Block-Iterative Algorithms with Underrelaxed Bregman Projections [PDF]

SIAM Journal on Optimization, 2002
The authors consider the convex feasibility problem of finding a point of the set \(C=\bigcap_{i=1}^{m} C_{i}\) where each \(C_{i}\) is a convex closed subset of \(R^{n}\). The usual block-iterative algorithms for this problem are based on the sequential orthogonal projections with possible relaxations.
Censor, Yair, Herman, Gabor T.
openaire   +1 more source

Coordinate descent iterations in fast affine projection algorithm [PDF]

IEEE Signal Processing Letters, 2005
We propose a new approach for real-time implementation of the fast affine projection (FAP) algorithm. This is based on exploiting the recently introduced dichotomous coordinate descent (DCD) algorithm, which is especially efficient for solving systems of linear equations on real-time hardware and software platforms since it is free of multiplication ...
Zakharov, Y, Albu, F
openaire   +2 more sources

Projection Classification Based Iterative Algorithm

IOP Conference Series: Materials Science and Engineering, 2015
Iterative algorithm has good performance as it does not need complete projection data in 3D image reconstruction area. It is possible to be applied in BGA based solder joints inspection but with low convergence speed which usually acts with x-ray Laminography that has a worse reconstruction image compared to the former one. This paper explores to apply
Ruiqiu Zhang, Chen Li, Wenhua Gao
openaire   +1 more source

Dynamical fat link fermions [PDF]

, 2004
The use of APE smearing or other blocking techniques in fermion actions can provide many advantages. There are many variants of these fat link actions in lattice QCD currently, such as FLIC fermions.
Alexandru, Anthony G. Williams, APE, Bietenholz, CSSM Lattice, DeGrand, Derek B. Leinweber, Duane, Falcioni, Hasenfratz, Kamleh, Kovacs, Leinweber, Liang, MILC, Morningstar, Stephenson, Waseem Kamleh   +17 more
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Gram filtering and sinogram interpolation for pixel-basis in parallel-beam X-ray CT reconstruction

, 2020
The key aspect of parallel-beam X-ray CT is forward and back projection, but its computational burden continues to be an obstacle for applications.
Entezari, Alireza, Shu, Ziyu
core   +1 more source

State of the art: iterative CT reconstruction techniques [PDF]

, 2015
Owing to recent advances in computing power, iterative reconstruction (IR) algorithms have become a clinically viable option in computed tomographic (CT) imaging. Substantial evidence is accumulating about the advantages of IR algorithms over established
Bastarrika, Gorka, DE CECCO, CARLO NICOLA, Geyer, Lucas L., LAGHI, ANDREA, Leipsic, Jonathon A., Meinel, Felix G., Nance, John W., Paul, Narinder S., RENGO, MARCO, Schoepf, U. Joseph   +9 more
core   +1 more source

Coordinate Descent Iterations in Pseudo Affine Projection Algorithm [PDF]

2005 IEEE International Symposium on Circuits and Systems, 2005
This paper introduces a new affine projection algorithm based on the dichotomous coordinate descent algorithm. A generalization for simplified Volterra filters is also made and its stability is improved by using a voice activity detector. The performance of the proposed algorithms for acoustic echo cancellation is assessed.
F. Albu, C. Kotropoulos
openaire   +1 more source