5,821 research outputs found
Inverse Avalanches On Abelian Sandpiles
A simple and computationally efficient way of finding inverse avalanches for
Abelian sandpiles, called the inverse particle addition operator, is presented.
In addition, the method is shown to be optimal in the sense that it requires
the minimum amount of computation among methods of the same kind. The method is
also conceptually nice because avalanche and inverse avalanche are placed in
the same footing.Comment: 5 pages with no figure IASSNS-HEP-94/7
Phase Diagram Of The Biham-Middleton-Levine Traffic Model In Three Dimensions
We study numerically the behavior of the Biham-Middleton-Levine traffic model
in three dimensions. Our extensive numerical simulations show that the phase
diagram for this model in three dimensions is markedly different from that in
one and two dimensions. In addition to the full speed moving as well as the
completely jamming phases, whose respective average asymptotic car speeds
equal one and zero, we observe an extensive region of car densities with
a low but non-zero average asymptotic car speed. The transition from this
extensive low average asymptotic car speed region to the completely jamming
region is at least second order. We argue that this low speed region is a
result of the formation of a spatially-limited-extended percolating cluster.
Thus, this low speed phase is present in dimensional
Biham-Middleton-Levine model as well.Comment: Minor clarifications, 1 figure adde
Statistics Of The Burst Model At Super-critical Phase
We investigate the statistics of a model of type-I X-ray burst [Phys. Rev. E,
{\bf 51}, 3045 (1995)] in its super-critical phase. The time evolution of the
burnable clusters, places where fire can pass through, is studied using simple
statistical arguments. We offer a simple picture for the time evolution of the
percentage of space covered by burnable clusters. A relation between the
time-average and the peak percentage of space covered by burnable clusters is
also derived.Comment: 11 Pages in Revtex 3.0. Two figures available by sending request to
[email protected]
Parity Problem With A Cellular Automaton Solution
The parity of a bit string of length is a global quantity that can be
efficiently compute using a global counter in time. But is it
possible to find the parity using cellular automata with a set of local rule
tables without using any global counter? Here, we report a way to solve this
problem using a number of binary, uniform, parallel and deterministic
cellular automata applied in succession for a total of time.Comment: Revtex, 4 pages, final version accepted by Phys.Rev.
Modeling of Perfluorocarbons Decomposition in Nitrogen Thermal Plasma
This paper develops an axisymmetric flow model to predict the flow field inside a directcurrent plasma torch reactor, where the magneto-hydrodynamic equations, including the continuity, momentum, energy and current continuity equations as well as turbulence transport equations are solved with a finite volume discretization in a segregated manner. The thermodynamic and transport coefficients of thermal plasma are obtained from the condition of local thermal equilibrium, whereas a kinetics model is employed to consider the production and destruction of species due to the chemical reactions in a decomposition process. Species transport phenomena arising in the decomposition process are described by the transport equations for different species. The perfluorocarbons decomposition characteristics in a well-type, non-transferred nitrogen torch reactor are analyzed by the proposed numerical model to disclose the influence of working parameters on the decomposition efficiency
Direct CP violation in two-body hadronic charmed meson decays
Motivated by the recent observation of CP violation in the charm sector by
LHCb, we study direct CP asymmetries in the standard model (SM) for the singly
Cabibbo-suppressed two-body hadronic decays of charmed mesons using the
topological-diagram approach. In this approach, the magnitude and the phase of
topological weak annihilation amplitudes which arise mainly from final-state
rescattering can be extracted from the data. Consequently, direct CP asymmetry
at tree level can be reliably estimated. In general, it
lies in the range . Short-distance QCD
penguins and penguin annihilation are calculated using QCD factorization. Their
effects are generally small, especially for modes. Since weak penguin
annihilation receives long-distance contributions from the color-allowed tree
amplitude followed by final-state rescattering, it is expected to give the
dominant contribution to the direct CP violation in the decays
and in which is absent. The maximal
, the direct CP asymmetry difference between the
above-mentioned two modes, allowed in the SM is around -0.25%, more than
away from the current world average of .Comment: 19 pages, 2 figures; typos correcte
Variant Reorientation in Single-crystal Shape-memory Alloys
In this work we model the variant reorientation in a single crystal NiMnGa magnetic shapememory alloy using the crystal-mechanics-based constitutive model of Thamburaja[1]. The model has been implemented in the ABAQUS/Explicit finite-element program by writing a user-material subroutine. Its numerical simulations quantitatively predict the mechanical response in simple compression and plain strain compression experiments to good accord
Quantum Convolutional Error Correction Codes
I report two general methods to construct quantum convolutional codes for
quantum registers with internal states. Using one of these methods, I
construct a quantum convolutional code of rate 1/4 which is able to correct one
general quantum error for every eight consecutive quantum registers.Comment: To be reported in the 1st NASA Conf. on Quantum Comp., uses
llncs.sty, 12 page
Comments on the Quark Content of the Scalar Meson
Based on the measurements of we determine, in
a model independent way, the allowed content in the scalar meson
. We find that, on the one hand, if this isoscalar resonance is a
pure state [ , a very
large -annihilation term will be needed to accommodate . On the other hand, the component of
should be small enough to avoid excessive induced
from the external -emission. Measurement of production in the
decay will be useful to test the above picture. For the
decay which is kinematically barely or even not
allowed, depending on the mass of , we find that the finite width
effect of plays a crucial role on the resonant three-body decay
.Comment: 12 pages, 2 figure
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