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101.
Winfried K. Grassmann Steve Drekic 《Methodology and Computing in Applied Probability》2008,10(1):73-83
A number of authors have recently suggested solving quasi birth-and-death (QBD) processes through the use of eigenvalue-based
methods. These methods take on a special form when there are multiple eigenvalues present. We investigate this problem in
a general setting as well as in the context of a specific preemptive priority queueing model.
相似文献
102.
Hermite四点插指公式 总被引:2,自引:0,他引:2
颜宇生 《应用数学与计算数学学报》2008,22(1)
文章利用Hermite插值基函数,将求解Hermite四点插指问题转换为求解8个派生出来的多项式插值问题,证明了Hermite四点插指公式的存在唯一性,并用两种方法构造出Hermite四点插指公式,最后给出了一个算例. 相似文献
103.
We consider hyperbolic systems of equations that have full sets of integrals along both characteristics. The best known example
of models of this type is given by two-dimensional open Toda chains. For systems that have integrals, we construct a differential
operator that takes integrals into symmetries. For systems of the chosen type, this proves the existence of higher symmetries
dependent on arbitrary functions.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 155, No. 2, pp. 344–355, May, 2008. 相似文献
104.
William S. Epling Gar B. Hoflund David M. Minahan 《Reaction Kinetics and Catalysis Letters》1999,67(2):225-232
Promoter loading level significantly affects the catalytic behavior of Zn/Cr spinel higher alcohol synthesis (HAS) catalysts.
In this study a 5.9 wt.% Pd-promoted Zn/Cr spinel with a 5 and 7 wt.% K promoter have been tested and compared. At 1500 psig
and 400°C, the catalyst containing 5 wt.% K results in the production of slightly more butanol, less methanol and more hydrocarbons.
Using ion scattering spectroscopy and X-ray photoelectron spectroscopy, differences are found between the two catalyst surfaces
which must be responsible for the differences in catalytic behavior. 相似文献
105.
设N是Banach空间X上的套,AlgN是相应的套代数。本文证明了,若套N中存在一个非平凡元在X中可补,那么AlgN上的每个可加Jordan高阶导子和每个可加三重Jordan高阶导子都是高阶导子。 相似文献
106.
A lattice Boltzmann model with higher‐order accuracy for the wave motion is proposed. The new model is based on the technique of the higher‐order moment of equilibrium distribution functions and a series of lattice Boltzmann equations in different time scales. The forms of moments are derived from the binary wave equation by designing the higher‐order dissipation and dispersion terms. The numerical results agree well with classical ones. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
107.
随着现代教育的发展,关注大学生的学习心理研究,提高全体学生的学习效率和效果,教育心理学逐步走入课堂,越来越被教育工作者所重视。许多教师广泛采用教育心理学的原理和理论结构来指导自己的教学实践,并且取得了令人满意的成效。本文采用理论联系实际的方法,对高等教育心理学在牛顿环实验教学中的应用进行了有益探索。 相似文献
108.
We use the higher covariant derivative regularization to investigate a new identity for Green’s functions. It relates certain
coefficients of the matter superfield vertex function for which one of the external matter legs is not chiral. Calculations
in the first nontrivial order (for the two-loop vertex function) demonstrate that the new identity also holds in the non-Abelian
Yang-Mills theory with matter fields. We demonstrate that the new identity follows because the three-loop integrals determining
the Gell-Mann-Low function are integrals of total derivatives.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 156, No. 2, pp. 270–281, August, 2008. 相似文献
109.
求出了(n-3)-filiform李代数的极大环面,并证明了(n-3)-filiform李代数是可完备化的. 相似文献
110.
This article derives from first principles a definition of equivalence for higher‐dimensional Hadamard matrices and thereby a definition of the automorphism group for higher‐dimensional Hadamard matrices. Our procedure is quite general and could be applied to other kinds of designs for which there are no established definitions for equivalence or automorphism. Given a two‐dimensional Hadamard matrix H of order ν, there is a Product Construction which gives an order ν proper n‐dimensional Hadamard matrix P(n)(H). We apply our ideas to the matrices P(n)(H). We prove that there is a constant c > 1 such that any Hadamard matrix H of order ν > 2 gives rise via the Product Construction to cν inequivalent proper three‐dimensional Hadamard matrices of order ν. This corrects an erroneous assertion made in the literature that ”P(n)(H) is equivalent to “P(n)(H′) whenever H is equivalent to H′.” We also show how the automorphism group of P(n)(H) depends on the structure of the automorphism group of H. As an application of the above ideas, we determine the automorphism group of P(n)(Hk) when Hk is a Sylvester Hadamard matrix of order 2k. For ν = 4, we exhibit three distinct families of inequivalent Product Construction matrices P(n)(H) where H is equivalent to H2. These matrices each have large but non‐isomorphic automorphism groups. © 2008 Wiley Periodicals, Inc. J Combin Designs 16: 507–544, 2008 相似文献