347,739 research outputs found
Optimal decision fusion and its application on 3D face recognition
Fusion is a popular practice to combine multiple classifiers or multiple modalities in biometrics. In this paper, optimal decision fusion (ODF) by AND rule and OR rule is presented. We show that the decision fusion can be done in an optimal way such that it always gives an improvement in terms of error rates over the classifiers that are fused. Both the optimal decision fusion theory and the experimental results on the FRGC 2D and 3D face data are given. Experiments show that the optimal decision fusion effectively combines the 2D texture and 3D shape information, and boosts the performance of the system
Target Type Tracking with PCR5 and Dempster's rules: A Comparative Analysis
In this paper we consider and analyze the behavior of two combinational rules
for temporal (sequential) attribute data fusion for target type estimation. Our
comparative analysis is based on Dempster's fusion rule proposed in
Dempster-Shafer Theory (DST) and on the Proportional Conflict Redistribution
rule no. 5 (PCR5) recently proposed in Dezert-Smarandache Theory (DSmT). We
show through very simple scenario and Monte-Carlo simulation, how PCR5 allows a
very efficient Target Type Tracking and reduces drastically the latency delay
for correct Target Type decision with respect to Demspter's rule. For cases
presenting some short Target Type switches, Demspter's rule is proved to be
unable to detect the switches and thus to track correctly the Target Type
changes. The approach proposed here is totally new, efficient and promising to
be incorporated in real-time Generalized Data Association - Multi Target
Tracking systems (GDA-MTT) and provides an important result on the behavior of
PCR5 with respect to Dempster's rule. The MatLab source code is provided inComment: 10 pages, 5 diagrams. Presented to Fusion 2006 International
Conference, Florence, Italy, July 200
Demazure Characters and Affine Fusion Rules
The Demazure character formula is applied to the Verlinde formula for affine
fusion rules. We follow Littelmann's derivation of a generalized
Littlewood-Richardson rule from Demazure characters. A combinatorial rule for
affine fusions does not result, however. Only a modified version of the
Littlewood-Richardson rule is obtained that computes an (old) upper bound on
the fusion coefficients of affine algebras. We argue that this is because
the characters of simple Lie algebras appear in this treatment, instead of the
corresponding affine characters. The Bruhat order on the affine Weyl group must
be implicated in any combinatorial rule for affine fusions; the Bruhat order on
subgroups of this group (such as the finite Weyl group) does not suffice.Comment: 23 pages, TeX, uses harvma
Fusion rules in conformal field theory
Several aspects of fusion rings and fusion rule algebras, and of their
manifestations in twodimensional (conformal) field theory, are described:
diagonalization and the connection with modular invariance; the presentation in
terms of quotients of polynomial rings; fusion graphs; various strategies that
allow for a partial classification; and the role of the fusion rules in the
conformal bootstrap programme.Comment: 68 pages, LaTeX. changed contents of footnote no.
Distributed Binary Detection over Fading Channels: Cooperative and Parallel Architectures
This paper considers the problem of binary distributed detection of a known
signal in correlated Gaussian sensing noise in a wireless sensor network, where
the sensors are restricted to use likelihood ratio test (LRT), and communicate
with the fusion center (FC) over bandwidth-constrained channels that are
subject to fading and noise. To mitigate the deteriorating effect of fading
encountered in the conventional parallel fusion architecture, in which the
sensors directly communicate with the FC, we propose new fusion architectures
that enhance the detection performance, via harvesting cooperative gain
(so-called decision diversity gain). In particular, we propose: (i) cooperative
fusion architecture with Alamouti's space-time coding (STC) scheme at sensors,
(ii) cooperative fusion architecture with signal fusion at sensors, and (iii)
parallel fusion architecture with local threshold changing at sensors. For
these schemes, we derive the LRT and majority fusion rules at the FC, and
provide upper bounds on the average error probabilities for homogeneous
sensors, subject to uncorrelated Gaussian sensing noise, in terms of
signal-to-noise ratio (SNR) of communication and sensing channels. Our
simulation results indicate that, when the FC employs the LRT rule, unless for
low communication SNR and moderate/high sensing SNR, performance improvement is
feasible with the new fusion architectures. When the FC utilizes the majority
rule, such improvement is possible, unless for high sensing SNR
Branes: from free fields to general backgrounds
Motivated by recent developments in string theory, we study the structure of
boundary conditions in arbitrary conformal field theories. A boundary condition
is specified by two types of data: first, a consistent collection of reflection
coefficients for bulk fields on the disk; and second, a choice of an
automorphism of the fusion rules that preserves conformal weights.
Non-trivial automorphisms correspond to D-brane configurations for
arbitrary conformal field theories. The choice of the fusion rule automorphism
amounts to fixing the dimension and certain global topological
features of the D-brane world volume and the background gauge field on it. We
present evidence that for fixed choice of the boundary conditions are
classified as the irreducible representations of some commutative associative
algebra, a generalization of the fusion rule algebra. Each of these irreducible
representations corresponds to a choice of the moduli for the world volume of
the D-brane and the moduli of the flat connection on it.Comment: 56 pages, LaTeX2e. Typos corrected; two references adde
Application of probabilistic PCR5 Fusion Rule for Multisensor Target Tracking
This paper defines and implements a non-Bayesian fusion rule for combining
densities of probabilities estimated by local (non-linear) filters for tracking
a moving target by passive sensors. This rule is the restriction to a strict
probabilistic paradigm of the recent and efficient Proportional Conflict
Redistribution rule no 5 (PCR5) developed in the DSmT framework for fusing
basic belief assignments. A sampling method for probabilistic PCR5 (p-PCR5) is
defined. It is shown that p-PCR5 is more robust to an erroneous modeling and
allows to keep the modes of local densities and preserve as much as possible
the whole information inherent to each densities to combine. In particular,
p-PCR5 is able of maintaining multiple hypotheses/modes after fusion, when the
hypotheses are too distant in regards to their deviations. This new p-PCR5 rule
has been tested on a simple example of distributed non-linear filtering
application to show the interest of such approach for future developments. The
non-linear distributed filter is implemented through a basic particles
filtering technique. The results obtained in our simulations show the ability
of this p-PCR5-based filter to track the target even when the models are not
well consistent in regards to the initialization and real cinematic
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