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91.
Eugene R. Speer 《Journal of statistical physics》1997,89(1-2):169-175
Abstruct The algebra describing a shock measure in the asymmetric simple exclusion model, seen from a second class particle, has finite-dimensional
representations if and only if the asymmetry parameterp of the model and the left and right asymptotic densitiesp
± of the shock satisfy [(1−p)/p]
r
=p
−(1−p
+)/p
+(1−p
−) for some integerr≥1; the minimal dimension of the representation is then 2r. These representations can be used to calculate correlation functions
in the model. 相似文献
92.
Arkady I. Leonov 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2008,59(2):333-359
The paper develops a continuum theory of weak viscoelastic nematodynamics of Maxwell type. It can describe the molecular elasticity
effects in mono-domain flows of liquid crystalline polymers as well as the viscoelastic effects in suspensions of uniaxially
symmetric particles in polymer fluids. Along with viscoelastic and nematic kinematics, the theory employs a general form of
weakly elastic thermodynamic potential and the Leslie–Ericksen–Parodi type constitutive equations for viscous nematic liquids,
while ignoring inertia effects and the Frank (orientation) elasticity in liquid crystal polymers. In general case, even the
simplest Maxwell model has many basic parameters. Nevertheless, recently discovered algebraic properties of nematic operations
reveal a general structure of the theory and present it in a simple form. It is shown that the evolution equation for director
is also viscoelastic. An example of magnetization exemplifies the action of non-symmetric stresses. When the magnetic field
is absent, the theory is reduced to the symmetric, fluid mechanical case with relaxation properties for both the stress and
director. Our recent analyses of elastic and viscous soft deformation modes are also extended to the viscoelastic case. The
occurrence of possible soft modes minimizes both the free energy and dissipation, and also significantly decreases the number
of material parameters. In symmetric linear case, the theory is explicitly presented in terms of anisotropic linear memory
functionals. Several analytical results demonstrate a rich behavior predicted by the developed model for steady and unsteady
flows in simple shearing and simple elongation. 相似文献
93.
In this paper we prove that the equational class generated by bounded BCK‐algebras is the variety generated by the class of finite simple bounded BCK‐algebras. To obtain these results we prove that every simple algebra in the equational class generated by bounded BCK‐algebras is also a relatively simple bounded BCK‐algebra. Moreover, we show that every simple bounded BCK‐algebra can be embedded into a simple integral commutative bounded residuated lattice. We extend our main results to some richer subreducts of the class of integral commutative bounded residuated lattices and to the involutive case. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
94.
A finite group G is said to be recognizable by spectrum, i.e., by the set of element orders, if every finite group H having the same spectrum as G is isomorphic to G. We prove that the simple linear groups L
n
(2k) are recognizable by spectrum for n = 2m ≥ 32.Original Russian Text Copyright © 2005 Vasil’ev A. V. and Grechkoseeva M. A.The authors were supported by the Russian Foundation for Basic Research (Grant 05-01-00797), the State Maintenance Program for the Leading Scientific Schools of the Russian Federation (Grant NSh-2069.2003.1), the Program “ Development of the Scientific Potential of Higher School” of the Ministry for Education of the Russian Federation (Grant 8294), the Program “Universities of Russia” (Grant UR.04.01.202), and a grant of the Presidium of the Siberian Branch of the Russian Academy of Sciences (No. 86-197).__________Translated from Sibirskii Matematicheskii Zhurnal, Vol. 46, No. 4, pp. 749–758, July–August, 2005. 相似文献
95.
Arturo Magidin 《Algebra Universalis》2002,48(2):133-143
We determine the dominion (in the sense of Isbell) of a subgroup H of a finite nonabelian simple group S in Var(S). We also obtain necessary and suficient conditions for H to be epimorphically embedded in S, and derive several examples, which generalize an example of B. H. Neumann. Finally, we extend the results to a variety generated
by a family of finite nonabelian simple groups.
Received May 12, 1999; accepted in final form April 9, 2002. 相似文献
96.
Yu. S. Kolesov 《Mathematical Notes》1997,62(5):623-628
For a number of meaningful examples, nonresonant wave-type equations are shown to be characterized by periodic dynamics.
Translated fromMatematicheskie Zametki, Vol. 62, No. 5, pp. 744–750, November, 1997.
Translated by O. V. Sipacheva 相似文献
97.
Philip L. H. Yu Yijun Sun Bimal K. Sinha 《Annals of the Institute of Statistical Mathematics》2002,54(4):861-878
In this paper we discuss the problem of estimating the common mean of a bivariate normal population based on paired data as well as data on one of the marginals. Two double sampling schemes with the second stage sampling being either a simple random sampling (SRS) or a ranked set sampling (RSS) are considered. Two common mean estimators are proposed. It is found that under normality, the proposed RSS common mean estimator is always superior to the proposed SRS common mean estimator and other existing estimators such as the RSS regression estimator proposed by Yu and Lam (1997, Biometrics, 53, 1070–1080). The problem of estimating the mean Reid Vapor Pressure (RVP) of regular gasoline based on field and laboratory data is considered. 相似文献
98.
用集成电路制成程序控制器,示教板性能稳定,寿命长,效果好,操作方便.其主要部分由电源、时钟、逻辑电路、输出驱动器四部分组成. 相似文献
99.
王芳华 《数学的实践与认识》2007,37(10):102-106
通过对单纯形法的分析和研究,提出了一种简易的单纯形表,并利用矩形法则进行计算而得到一种改进的单纯形法.结果表明该法简单易行,并减少了计算量和存储量. 相似文献
100.
M. A. Grechkoseeva 《Siberian Mathematical Journal》2007,48(1):73-75
We prove that the nonisomorphic simple groups B
n
(q) and C
n
(q) have different sets of element orders.
Original Russian Text Copyright ? 2007 Grechkoseeva M. A.
__________
Translated from Sibirskiĭ Matematicheskiĭ Zhurnal, Vol. 48, No. 1, pp. 89–92, January–February, 2007. 相似文献