48,599 research outputs found
State determination: an iterative algorithm
An iterative algorithm for state determination is presented that uses as
physical input the probability distributions for the eigenvalues of two or more
observables in an unknown state . Starting form an arbitrary state
, a succession of states is obtained that converges to
or to a Pauli partner. This algorithm for state reconstruction is
efficient and robust as is seen in the numerical tests presented and is a
useful tool not only for state determination but also for the study of Pauli
partners. Its main ingredient is the Physical Imposition Operator that changes
any state to have the same physical properties, with respect to an observable,
of another state.Comment: 11 pages 3 figure
Statistical-mechanical iterative algorithms on complex networks
The Ising models have been applied for various problems on information
sciences, social sciences, and so on. In many cases, solving these problems
corresponds to minimizing the Bethe free energy. To minimize the Bethe free
energy, a statistical-mechanical iterative algorithm is often used. We study
the statistical-mechanical iterative algorithm on complex networks. To
investigate effects of heterogeneous structures on the iterative algorithm, we
introduce an iterative algorithm based on information of heterogeneity of
complex networks, in which higher-degree nodes are likely to be updated more
frequently than lower-degree ones. Numerical experiments clarified that the
usage of the information of heterogeneity affects the algorithm in BA networks,
but does not influence that in ER networks. It is revealed that information of
the whole system propagates rapidly through such high-degree nodes in the case
of Barab{\'a}si-Albert's scale-free networks.Comment: 7 pages, 6 figure
Gaussian elimination as an iterative algorithm
Gaussian elimination (GE) for solving an linear system of equations is the archetypical direct method of numerical linear algebra, as opposed to iterative. In this note we want to point out that GE has an iterative side too
A simple iterative algorithm for maxcut
We propose a simple iterative (SI) algorithm for the maxcut problem through
fully using an equivalent continuous formulation. It does not need rounding at
all and has advantages that all subproblems have explicit analytic solutions,
the cut values are monotonically updated and the iteration points converge to a
local optima in finite steps via an appropriate subgradient selection.
Numerical experiments on G-set demonstrate the performance. In particular, the
ratios between the best cut values achieved by SI and the best known ones are
at least and can be further improved to at least by a
preliminary attempt to break out of local optima.Comment: 30 pages, 1 figure. Subgradient selection, cost analysis and local
breakout are adde
Iterative algorithm for reconstruction of entangled states
An iterative algorithm for the reconstruction of an unknown quantum state
from the results of incompatible measurements is proposed. It consists of
Expectation-Maximization step followed by a unitary transformation of the
eigenbasis of the density matrix. The procedure has been applied to the
reconstruction of the entangled pair of photons.Comment: 4 pages, no figures, some formulations changed, a minor mistake
correcte
Stopping Criterion for the Mean Shift Iterative Algorithm
Image segmentation is a critical step in computer vision tasks constituting
an essential issue for pattern recognition and visual interpretation. In this
paper, we propose a new stopping criterion for the mean shift iterative
algorithm by using images defined in Zn ring, with the goal of reaching a
better segmentation. We carried out also a study on the weak and strong of
equivalence classes between two images. An analysis on the convergence with
this new stopping criterion is carried out too.Comment: Have 8 pages. Is the first version of the more general pape
- âŠ