461 research outputs found
Formación del modelo óptimo del cluster industrial de empresas de confección chinas basado en la gestión de la zona económica estratégica
El artículo analiza el mecanismo para desarrollar un modelo óptimo de un clúster industrial asociado con la formación de zonas económicas estratégicas utilizando el ejemplo de las
empresas textiles chinas. se está resolviendo el problema de determinar el conjunto óptimo de zonas económicas estratégicas prometedoras para maximizar los ingresos de las ventas de productos de clúster industrial en un conjunto dado de zonas económicas estratégicas. se determina la condición de la empresa, que se corresponde más estrechamente con las necesidades del mercado en cuanto al volumen y la variedad de productos de acuerdo con la
composición y capacidad de las áreas estratégicas de negocios. se está buscando una política de inversión e innovación que asegure la transformación evolutiva de la arquitectura empresarial de acuerdo con la visión del estado actual y basada en minimizar las inversiones atraídas. se
investigan el enfoque de clúster y la integración vertical, lo que puede proporcionar una ventaja competitiva sostenible para las empresas de la industria ligera durante muchos años. se propone y prueba un modelo original para crear un grupo industrial en el ejemplo de las empresas de costura en china
Entropy Analysis in \pi^{+}\rp and \rK^{+}\rp Collisions at GeV
The entropy properties are analyzed by Ma's coincidence method in
\pi^{+}\rp and \rK^{+}\rp collisions of the NA22 experiment at 250 GeV/
incident momentum. By using the R\'{e}nyi entropies, we test the scaling law
and additivity properties in rapidity space. The behavior of the R\'{e}nyi
entropies as a function of the average number of particles is investigated. The
results are compared with those from the {\sc Pythia} Monte Carlo event
generator.Comment: LaTeX, 11 pages, 5 figure to be appeared in Acta Phys. Pol.
Direct J/Psi hadroproduction in k_\perp-factorization and the color octet mechanism
The hadroproduction of direct J/Psi in the framework of the
k_\perp-factorization approach is studied. The color-singlet contribution is
essentially larger than in the collinear approach but is still an order of
magnitude below the data. The deficit may be well described by the color octet
contribution with the value of the matrix element
substantially decreased in comparison with the fits in the collinear
factorization. This should lead to a reduction of the large transverse
polarization, predicted in the collinear approach.Comment: 3 pages, LaTeX, 2 eps figures, final PRD versio
Sum rules and dualities for generalized parton distributions: is there a holographic principle?
To leading order approximation, the physical content of generalized parton
distributions (GPDs) that is accessible in deep virtual electroproduction of
photons or mesons is contained in their value on the cross-over trajectory.
This trajectory separates the t-channel and s-channel dominated GPD regions.
The underlying Lorentz covariance implies correspondence between these two
regions through their relation to GPDs on the cross-over trajectory. This point
of view leads to a family of GPD sum rules which are a quark analogue of finite
energy sum rules and it guides us to a new phenomenological GPD concept. As an
example, we discuss the constraints from the JLab/Hall A data on the dominant
u-quark GPD H. The question arises whether GPDs are governed by some kind of
holographic principle.Comment: 45 pages, 4 figures, Sect. 2 reorganized for clarity. Typos in Eq.
(20) corrected. 4 new refs. Matches published versio
J/psi plus jet associated production in two-photon collisions at next-to-leading order
We calculate the cross section of J/psi plus jet inclusive production in
gamma gamma collisions at next-to-leading order within the factorization
formalism of nonrelativistic quantum chromodynamics (NRQCD) focusing on direct
photoproduction. Apart from direct J/psi production, we also include the
feed-down from directly-produced chi_{cJ} and psi' mesons. We discuss the
analytical calculation, in particular the treatment of the various types of
singularities and the NRQCD operator renormalization, in some detail. We
present theoretical predictions for the future e^+e^- linear collider TESLA,
taking into account both brems- and beamstrahlung.Comment: 43 pages, 11 figure
Heavy Quark Fragmentation Functions for D-wave Quarkonium and Charmed Beauty Mesons
At the large transverse momentum region, the production of heavy-heavy
bound-states such as charmonium, bottomonium, and mesons in high
energy and hadronic collisions is dominated by parton fragmentation.
We calculate the heavy quark fragmentation functions into the D-wave quarkonium
and mesons to leading order in the strong coupling constant and in
the non-relativistic expansion. In the meson case, one set of its
D-wave states is expected to lie below the open flavor threshold. The total
fragmentation probability for a antiquark to split into the D-wave
mesons is about , which implies that only 2\% of
the total pseudo-scalar ground state comes from the cascades of these
orbitally excited states.Comment: 26 pages in RevteX and 3 figures in postscript. Also available at
http://www.ph.utexas.edu/~cheung/paper.htm
Heavy quarkonium: progress, puzzles, and opportunities
A golden age for heavy quarkonium physics dawned a decade ago, initiated by
the confluence of exciting advances in quantum chromodynamics (QCD) and an
explosion of related experimental activity. The early years of this period were
chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in
2004, which presented a comprehensive review of the status of the field at that
time and provided specific recommendations for further progress. However, the
broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles
could only be partially anticipated. Since the release of the YR, the BESII
program concluded only to give birth to BESIII; the -factories and CLEO-c
flourished; quarkonium production and polarization measurements at HERA and the
Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the
deconfinement regime. All these experiments leave legacies of quality,
precision, and unsolved mysteries for quarkonium physics, and therefore beg for
continuing investigations. The plethora of newly-found quarkonium-like states
unleashed a flood of theoretical investigations into new forms of matter such
as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the
spectroscopy, decays, production, and in-medium behavior of c\bar{c}, b\bar{b},
and b\bar{c} bound states have been shown to validate some theoretical
approaches to QCD and highlight lack of quantitative success for others. The
intriguing details of quarkonium suppression in heavy-ion collisions that have
emerged from RHIC have elevated the importance of separating hot- and
cold-nuclear-matter effects in quark-gluon plasma studies. This review
systematically addresses all these matters and concludes by prioritizing
directions for ongoing and future efforts.Comment: 182 pages, 112 figures. Editors: N. Brambilla, S. Eidelman, B. K.
Heltsley, R. Vogt. Section Coordinators: G. T. Bodwin, E. Eichten, A. D.
Frawley, A. B. Meyer, R. E. Mitchell, V. Papadimitriou, P. Petreczky, A. A.
Petrov, P. Robbe, A. Vair
Critical Correlations of Wilson Lines in SU(3) and the High Energy Cross Section
We discuss deep inelastic scattering at high energies as a critical
phenomenon in 2+1 space - time dimensions. In the limit of Bjorken ,
SU(3) with quark fields becomes a critical theory with a diverging
correlation length where the
exponent is obtained from the center group Z(3) of SU(3). We
conjecture that the dipole wave function of the virtual photon for transverse
sizes obeys correlation scaling before exponentially decaying for distances larger than
the correlation length. Using this behavior combined with different
-independent dipole proton cross sections we calculate the proton structure
function and compare with the experimental data. We take the good agreement
with the measured proton structure function F as an indication that
at high energies dimensional reduction to an effective three dimensional theory
with a critical point occurs.Comment: 21 pages, 3 figure
Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment
This paper describes an analysis of the angular distribution of W->enu and
W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with
the ATLAS detector at the LHC in 2010, corresponding to an integrated
luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and
the missing transverse energy, the W decay angular distribution projected onto
the transverse plane is obtained and analysed in terms of helicity fractions
f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV
and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw
> 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour,
are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017
+/- 0.030, where the first uncertainties are statistical, and the second
include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables,
revised author list, matches European Journal of Physics C versio
Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS
The chi_b(nP) quarkonium states are produced in proton-proton collisions at
the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS
detector. Using a data sample corresponding to an integrated luminosity of 4.4
fb^-1, these states are reconstructed through their radiative decays to
Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks
corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new
structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is
also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes.
This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table,
corrected author list, matches final version in Physical Review Letter
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