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991.
Exactly solvable models through the generalized empty interval method,for multi-species interactions
A. Aghamohammadi M. Alimohammadi M. Khorrami 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,31(3):371-378
Multi-species reaction-diffusion systems, with nearest-neighbor interaction on a one-dimensional lattice are considered. Necessary
and sufficient constraints on the interaction rates are obtained, that guarantee the closedness of the time evolution equation
for E
n(t)'s, the expectation value of the product of certain linear combination of the number operators on n consecutive sites at time t. The constraints are solved for the single-species left-right-symmetric systems. Also, examples of multi-species system for
which the evolution equations of E
n(t)'s are closed, are given.
Received 25 September 2002 / Received in final form 3 December 2002 Published online 14 February 2003
RID="a"
ID="a"e-mail: mamwad@iasbs.ac.ir 相似文献
992.
K. Mallick P. Marcq 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,31(4):553-561
We study analytically and numerically the problem of a nonlinear mechanical oscillator with additive noise in the absence
of damping. We show that the amplitude, the velocity and the energy of the oscillator grow algebraically with time. For Gaussian
white noise, an analytical expression for the probability distribution function of the energy is obtained in the long-time
limit. In the case of colored, Ornstein-Uhlenbeck noise, a self-consistent calculation leads to (different) anomalous diffusion
exponents. Dimensional analysis yields the qualitative behavior of the prefactors (generalized diffusion constants) as a function
of the correlation time.
Received 10 October 2002 Published online 6 March 2003
RID="a"
ID="a"e-mail: mallick@spht.saclay.cea.fr 相似文献
993.
While approaching the target body, the deep-space probe is orbiting hyperbolically before the maneuver. We discuss the variation of perturbed hyperbolic orbit using the method similar to that used in elliptic orbit. Ephemeris calculating and orbit control will benefit from the given analytical solution. 相似文献
994.
We study the pure point spectrum of the energy operator H(P
) of a many-particle charged quantum system in a homogeneous magnetic field based on the results in our previous work under fixation of the sum P
of the pseudomomentum components of the system. We prove that the discrete spectrum H(P
) of a short-range system is infinite under some conditions (which, for example, hold for a system of two oppositely charged particles) even in the case of a finitely supported potential. For a long-range system of the type of a (+)-ion of an atom (including the ion), the discrete spectrum is infinite. 相似文献
995.
Large Deviation Principle for Additive Functionals of Brownian Motion Corresponding to Kato Measures
Let (B
t
,P
W
x
) be the Brownian motion. Let be a Radon measure in the Kato class and A
t
the additive functional associated with . We prove that A
t
/t obeys the large deviation principle. 相似文献
996.
CARLOS MARIO GÓMEZ GÓMEZ 《Natural Resource Modeling》2001,14(1):5-30
ABSTRACT. The purpose of the paper is to contribute to the narrowing of the distance between formal theory and practical environmental policy design. We formulate a general and comprehensive theoretical model in order to take into account the different informational and technological problems which characterize the definition and implementation of environmental taxes in a second best world where there also are distortionary taxes. Having formalized these problems, we present a general model which allows us to discuss the existence of efficient and implementable environmental quality objectives and policy instruments, and to analyze many particular cases. 相似文献
997.
Let t be a continuous Markov chain on N states. Consider adjoining a Brownian motion with this Markov chain so that the drift and the variance take different values when t is in different states. This new process Zt is a hidden Markov process. We study the probability distribution of the first passage time for Zt.Our result, when applied to the stock market, provides an explicit mathematical interpretation of the fact that in finite time, there is positive probability for the bull (bear) market to become bear (bull). 相似文献
998.
V. V. Sapunov 《Journal of Applied Spectroscopy》2001,68(5):727-735
For solutions of the complexes of phthalocyanine (PhC) with magnesium (Mg-PhC) and of tetrachloromethyl-PhC with zinc (Zn-PhCCh) in mixtures of glycerin with dimethyl formamide (DMF) and for Zn-PhCCh in toluene and DMF it has been found that the electron absorption spectra substantially depend on the substance concentration. It is shown that these changes are attributable to the association of the molecules of pigments. The number of molecules in the associates and the equilibrium constants for this association are determined. The formation of the trimers of Mg-PhC in binary solutions and the dimers of Zn-PhCCh in toluene, DNF, and binary solutions has been established. It has been found that on association the Q absorption bands of the pigments shift to shorter wavelengths as compared to the bands of the monomers. For the Mg-PhC trimers, the shift is = 1410 cm–1, while for the Zn-PhCCh dimers it is 990 cm–1 in toluene, 930 cm–1 in DMF, and 925 cm–1 in the mixture of DMF with glycerin. It is concluded that the structure of the trimers and dimers is of the type of a stack in which molecules are arranged in parallel one above the other at a distance of 3.5 to 4.0 Å between the planes of the molecules. In association, the fluorescence intensity of the pigments decreases substantially (the decrease corresponds to the decrease in the concentration of the monomer molecules of phthalocyanines), with the fluorescence spectra remaining unchanged. Consequently, the associates of the pigments do not display pronounced fluorescence. 相似文献
999.
Sergei V. Zubov 《Southeast Asian Bulletin of Mathematics》2000,24(1):155-172
Consider a new concept of stability of the so-called rated motion of a system of an ordinary differential equations. A rated motion need not be a solution of this system at all. In terms of Lyapunovs direct method, formulate and prove certain statements about rated stability, asymptotically rated stability, and rated unstability of zero motion of a system of an ordinary differential equations.AMS Subject Classification (1991): 34D05 34D35 93D30 93D20 相似文献
1000.
More on P-Stable Convex Sets in Banach Spaces 总被引:2,自引:0,他引:2
We study the asymptotic behavior and limit distributions for sums S
n =bn
-1 i=1
n i,where
i, i 1, are i.i.d. random convex compact (cc) sets in a given separable Banach space B and summation is defined in a sense of Minkowski. The following results are obtained: (i) Series (LePage type) and Poisson integral representations of random stable cc sets in B are established; (ii) The invariance principle for processes S
n(t) =bn
-1 i=1
[nt] i, t[0, 1], and the existence of p-stable cc Levy motion are proved; (iii) In the case, where
i are segments, the limit of S
n is proved to be countable zonotope. Furthermore, if B = R
d
, the singularity of distributions of two countable zonotopes Yp
1, 1,Yp
2, 2, corresponding to values of exponents p
1, p
2 and spectral measures
1,
2, is proved if either p
1 p
2 or
1
2; (iv) Some new simple estimates of parameters of stable laws in R
d
, based on these results are suggested. 相似文献