34,986 research outputs found
Application of Pad\'{e} interpolation to stationary state problems
If the small and large coupling behavior of a physical system can be computed
perturbatively and expressed respectively as power series in a coupling
parameter and , a Pad\'{e} approximant embracing the two series can
interpolate between these two limits and provide an accurate estimate of the
system's behavior in the generally intractable intermediate coupling regime.
The methodology and validity of this approach are illustrated by considering
several stationary state problems in quantum mechanics.Comment: RevTeX4, 7 pages (including 7 tables); v4 typos correcte
Pion Interferometry for Hydrodynamical Expanding Source with a Finite Baryon Density
We calculate the two-pion correlation function for an expanding hadron source
with a finite baryon density. The space-time evolution of the source is
described by relativistic hydrodynamics and the Hanbury-Brown-Twiss (HBT)
radius is extracted after effects of collective expansion and multiple
scattering on the HBT interferometry have been taken into account, using
quantum probability amplitudes in a path-integral formalism. We find that this
radius is substantially smaller than the HBT radius extracted from the
freeze-out configuration.Comment: 4 pages, 2 figure
Piecewise-polynomial associated transform macromodeling algorithm for fast nonlinear circuit simulation
We present a piecewise-polynomial based associated transform algorithm (PWPAT) for macromodeling nonlinear circuits in system-level circuit design. The generated reduced model can provide both global and local accuracies with the most compact dimension. Numerical examples compare it with existing algorithms and verify its superior accuracy in higher order harmonics simulation over traditional Trajectory Piecewise-Linear (TPWL) approach. Ā© 2013 IEEE.published_or_final_versio
Pion Interferometry for a Granular Source of Quark-Gluon Plasma Droplets
We examine the two-pion interferometry for a granular source of quark-gluon
plasma droplets. The evolution of the droplets is described by relativistic
hydrodynamics with an equation of state suggested by lattice gauge results.
Pions are assumed to be emitted thermally from the droplets at the freeze-out
configuration characterized by a freeze-out temperature . We find that the
HBT radius decreases if the initial size of the droplets decreases.
On the other hand, depends on the droplet spatial distribution and
is relatively independent of the droplet size. It increases with an increase in
the width of the spatial distribution and the collective-expansion velocity of
the droplets. As a result, the value of can lie close to
for a granular quark-gluon plasma source. The granular model of the emitting
source may provide an explanation to the RHIC HBT puzzle and may lead to a new
insight into the dynamics of the quark-gluon plasma phase transition.Comment: 5 pages, 4 figure
Baryon deceleration by strong chromofields in ultrarelativistic nuclear collisions
It is assumed that strong chromofields are generated at early stages of
ultrarelativistic heavy-ion collisions which give rise to a collective
deceleration of net baryons from colliding nuclei. We have solved classical
equations of motion for baryonic slabs under the action of a time-dependent
longitudinal chromoelectric field. It is demonstrated that the slab final
rapidities are rather sensitive to the strength and decay time of the
chromofield as well as to the back reaction of the produced partonic plasma.
The net-baryon rapidity loss of about 2 units, found for most central Au-Au
collisions at RHIC, can be explained by the action of chromofields with the
initial energy density of about 50 GeV/fm^3. Predictions for the baryon
stopping at the LHC are made.Comment: 10 pages in revtex, 3 eps figure
Robust level-set-based inverse lithography
Level-set based inverse lithography technology (ILT) treats photomask design for microlithography as an inverse mathematical problem, interpreted with a time-dependent model, and then solved as a partial differential equation with finite difference schemes. This paper focuses on developing level-set based ILT for partially coherent systems, and upon that an expectation-orient optimization framework weighting the cost function by random process condition variables. These include defocus and aberration to enhance robustness of layout patterns against process variations. Results demonstrating the benefits of defocus-aberration-aware level-set based ILT are presented. Ā© 2011 Optical Society of America.published_or_final_versio
Penicillium marneffei Infection in AIDS
Penicillium marneffei is a dimorphic fungus which is endemic in Southeast Asia. It is an opportunistic pathogen which has emerged to become an AIDS-defining illness in the endemic areas. Early diagnosis with prompt initiation of treatment is crucial for its management. Prompt diagnosis can often be established through careful cytological and histological examination of clinical specimens although microbiological culture remains the gold standard for its diagnosis. Standard antifungal treatment for AIDS patients with penicilliosis is well established. Highly active antiretroviral therapy should be started early together with the antifungal treatment. Special attention should be paid to potential drug interaction between antiretroviral and antifungal treatments. Secondary prophylaxis may be discontinued with a low risk of relapse of the infection once the immune dysfunction has improved
Design of CRLH millimeter-wave passive filters in standard CMOS process
A novel approach to design millimeter-wave passive filters is presented using composite right/left-handed (CRLH) structures in a standard CMOS process. The filter is composed of left-handed open split-ring resonators (OSRR) or open complementary split-ring resonators (OCSRR). Such approach leads to a significant reduction in the on-chip area of the filter. It is also straightforward to construct similar filters based on the resonators' equivalent circuit models. Ā©2009 IEEE.published_or_final_versionThe IEEE International Conference of Electron Devices and Solid-State Circuits (EDSSC 2009), Xian, China, 25-27 November 2009. In Proceedings of the IEEE International Conference on Electron Devices and Solid-State Circuits, 2009, p. 1-
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