12,805 research outputs found
A Hybrid Quantum Encoding Algorithm of Vector Quantization for Image Compression
Many classical encoding algorithms of Vector Quantization (VQ) of image
compression that can obtain global optimal solution have computational
complexity O(N). A pure quantum VQ encoding algorithm with probability of
success near 100% has been proposed, that performs operations 45sqrt(N) times
approximately. In this paper, a hybrid quantum VQ encoding algorithm between
classical method and quantum algorithm is presented. The number of its
operations is less than sqrt(N) for most images, and it is more efficient than
the pure quantum algorithm.
Key Words: Vector Quantization, Grover's Algorithm, Image Compression,
Quantum AlgorithmComment: Modify on June 21. 10pages, 3 figure
Parton Interpretation and Twist-4 Parton Distributions
Through explicit examples we show that twist-4 parton distributions have no
parton interpretation in the sense that parton or partons inside a hadron can
carry the momentum fraction of the hadron with or . The
studied twist-4 parton distributions of collinear factoization are
power-divergent for . The corresponding transverse momentum
dependent parton distributions have also
no parton interpretation. They are finite. The implications of our results
are discussed.Comment: 11 pages, 3 figure
An experiential approach to developing teachers’ understanding of service-learning
Version of RecordPublishe
Tailoring of motional states in double-well potentials by time-dependent processes
We show that the vibrational state tailoring method developed for molecular
systems can be applied for cold atoms in optical lattices. The original method
is based on a three-level model interacting with two strong laser pulses in a
counterintuitive sequence [M. Rodriguez et al., Phys. Rev. A 62, 053413
(2000)]. Here we outline the conditions for achieving similar dynamics with
single time-dependent potential surfaces. It is shown that guided switching
between diabatic and adiabatic evolution has an essential role in this system.
We also show that efficient and precise tailoring of motional states in optical
lattices can be achieved, for instance, simply by superimposing two lattices
and moving them with respect to each other.Comment: 9 pages, 11 figures, 25 references; accepted to PRA; v2: minor
explanatory remarks added & typos correcte
QCD Factorization of Quasi Generalized Gluon Distributions
We study the factorization relations between quasi gluon GPDs and twist-2
GPDs. The perturbative coefficient functions are obtained at one-loop level.
They are free from any collinear- or I.R. divergences. Unlike the case of the
factorization of quasi quark GPDs at one-loop, we have to add ghost
contributions for the factorization of quasi gluon GPDs in order to obtain
gauge-invariant results. In general, operators will be mixed beyond tree-level.
Our work shows that the mixing pattern of the nonlocal operators in quasi gluon
GPDs is the same as local operators, i.e., the nonlocal operators considered
are mixed with gauge-invariant operators, BRST-variation operators and
operators involving EOM operator. The factorization relations are obtained for
all quasi gluon GPDs. Taking the forward limit, we also obtain the relations
between quasi gluon PDFs and twist-2 PDFs.Comment: 23 pages, 5 figures, published versio
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