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961.
We study the deterministic dynamics of non‐interacting classical gas particles confined to a one‐dimensional box as a pedagogical toy model for the relaxation of the Boltzmann distribution towards equilibrium. Hard container walls alone induce a uniform distribution of the gas particles at large times. For the relaxation of the velocity distribution we model the dynamical walls by independent scatterers. The Markov property guarantees a stationary but not necessarily thermal velocity distribution for the gas particles at large times. We identify the conditions for physical walls where the stationary velocity distribution is the Maxwell distribution. For our numerical simulation we represent the wall particles by independent harmonic oscillators. The corresponding dynamical map for oscillators with a fixed phase (Fermi–Ulam accelerator) is chaotic for mesoscopic box dimensions. 相似文献
962.
963.
利用素理想和环的零因子技巧,讨论泛复系数代数方程根的规律,得到了抛物复系数代数方程f(x)=(an bnk)x^n (an-1 bn-1k)x^n-1 …(a1 b1k)x (a0 b0k)=0(这里虚单位k满足k^2=0)的准确解;而对于双曲复系数代数方程f(x)=(an bnj)x^n (an-1 bn-1j)x^n-1+…+(a1 b1j)x (a0 b0j)=0(这里虚单位j满足j^2-1=0),我们将方程转换成方程组,给出了方程的具体解法,并估计了在双曲复数域H中的根的个数。 相似文献
964.
965.
The well-known factorization theorem of Lozanovski? may be written in the form L1≡E⊙E′, where ⊙ means the pointwise product of Banach ideal spaces. A natural generalization of this problem would be the question when one can factorize F through E , i.e., when F≡E⊙M(E,F), where M(E,F) is the space of pointwise multipliers from E to F . Properties of M(E,F) were investigated in our earlier paper [41] and here we collect and prove some properties of the construction E⊙F. The formulas for pointwise product of Calderón–Lozanovski? Eφ-spaces, Lorentz spaces and Marcinkiewicz spaces are proved. These results are then used to prove factorization theorems for such spaces. Finally, it is proved in Theorem 11 that under some natural assumptions, a rearrangement invariant Banach function space may be factorized through a Marcinkiewicz space. 相似文献
966.
A. Sankaranarayanan 《Lithuanian Mathematical Journal》2007,47(3):277-310
We study the sixth-power moments of certain L-functions belonging to a sub-class of the Selberg’s class on the critical line and, using this, we conclude an upper bound
for the fourth-power moments of certain L-functions related to GL
3 on the critical line. This is an analogue of the upper bound for the twelfth-power moment of the Riemann zeta-function on
the critical line.
Published in Lietuvos Matematikos Rinkinys, Vol. 47, No. 3, pp. 341–380, July–September, 2007. 相似文献
967.
V. P. Maslov 《Theoretical and Mathematical Physics》2008,156(2):1228-1229
Taking the interaction of particles into account in a new theory of nucleation leads to the occurrence of a phase transition
in the Van der Waals theory.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 156, No. 2, pp. 303–304, August, 2008. 相似文献
968.
This paper focuses on multi-objective large-scale non-linear programming (MOLSNLP) problems with block angular structure. We extend the technique for order preference by similarity ideal solution (TOPSIS) to solve them. Compromise (TOPSIS) control minimizes the measure of distance, provided that the closest solution should have the shortest distance from the positive ideal solution (PIS) as well as the longest distance from the negative ideal solution (NIS). As the measure of “closeness” LP-metric is used. Thus, we reduce a q-dimensional objective space to a two-dimensional space by a first-order compromise procedure. The concept of a membership function of fuzzy set theory is used to represent the satisfaction level for both criteria. Moreover, we derive a single objective large-scale non-linear programming (LSNLP) problem using the max–min operator for the second-order compromise operation. Finally, a numerical illustrative example is given to clarify the main results developed in this paper. 相似文献
969.
970.
P. J. de Paepe 《Czechoslovak Mathematical Journal》2003,53(1):77-81
Examples of non-finitely generated function algebras on planar sets with small maximal ideal spaces are given. 相似文献