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61.
I.M. Longman 《Journal of Computational and Applied Mathematics》1984,10(2):141-146
The approximate solution of the finite moment problem , k = 1, 2, 3, …, is considered. This problem is related to the problem of finding a best polynomial least squares approximation to a given function in [0,1]. The connection with Laplace transform inversion is emphasized, and a set of special square matrices with integral elements is introduced, which has an intimate relation to the above two problems. These matrices are the well-known inverses of finite segments of the infinite Hilbert matrix. 相似文献
62.
非平稳ρ混合序列的完全收敛性 总被引:4,自引:1,他引:3
本文进一步研究了ρ-混合序列的完全收敛性,讨论了无界非平稳情形完全收敛性成立的充分和必要条件,获得了理想的结果. 相似文献
63.
本文首先修正了文献[2]中的定义1.2,然后给出了由κ元(?)级 de Bruijn-Good图的1-因子构成的变换图的结构,得到了它与分配多面体图(graph of assign-ment polytope)的关系,从而得知它具有一些好的性质. 相似文献
64.
Stuart G. Hoggar 《Geometriae Dedicata》1998,69(3):287-289
An earlier computer calculation produced the vertices of a polytope in quaternionic 4-space, and determined their mutual angles all to be arccos (1/3). This note establishes a computer-independent verification. 相似文献
65.
A. C. Benim 《国际流体数值方法杂志》1989,9(3):289-303
A finite element formulation of enclosed turbulent diffusion flames is presented. A primitive variables approach is preferred in the analysis. A mixed interpolation is employed for the velocity and pressure. In the solution of the Navier-Stokes equations, a segregated formulation is adopted, where the pressure discretization equation is obtained directly from the discretized continuity equation, considering the velocity-pressure relationships in the discretized momentum equations. The state of turbulence is defined by a κ–? model. Near solid boundaries, a wall function approach is employed. The combustion rates are estimated using the eddy dissipation concept. The expensive direct treatment of the integrodifferential equations of radiation is avoided by employing the moment method, which allows the derivation of an approximate local field equation for the radiation intensity. The proposed finite element model is verified by investigating a technical turbulent diffusion flame of semi-industrial size, and comparing the results with experiments and finite difference predictions. 相似文献
66.
Kaoru Hirota 《Fuzzy Sets and Systems》1981,5(1):31-46
In the field of pattern recognition or decision making theory, the important subjects are as follows: (1) ambiguity of property of objects, (2) variety of character of objects, (3) subjectivity of observers, (4) evolution of knowledge of observers (i.e. learning). Considering these points, the concept of probabilistic set is proposed. It is based on both probability theory and fuzzy concepts. A probabilistic set on a total space is defined by a point wise measurable function from a parameter space (which is a probability space) to a characteristic space (which is a measurable space). It is shown that the family of all probabilistic sets constitutes a complete pseudo-Boolean algebra. Moment analysis is possible by using a probability measure of the parameter space. Other useful concepts are also mentioned such as probabilistic mappings and expected cardinal numbers. 相似文献
67.
In this paper, we present a novel graph-theoretical approach for representing a wide variety of sequence analysis problems
within a single model. The model allows incorporation of the operations “insertion”, “deletion”, and “substitution”, and various
parameters such as relative distances and weights. Conceptually, we refer the problem as the minimum weight common mutated sequence (MWCMS) problem. The MWCMS model has many applications including multiple sequence alignment problem, the phylogenetic analysis, the DNA sequencing
problem, and sequence comparison problem, which encompass a core set of very difficult problems in computational biology.
Thus the model presented in this paper lays out a mathematical modeling framework that allows one to investigate theoretical
and computational issues, and to forge new advances for these distinct, but related problems.
Through the introduction of supernodes, and the multi-layer supergraph, we proved that MWCMS is -complete. Furthermore, it was shown that a conflict graph derived from the multi-layer supergraph has the property that a
solution to the associated node-packing problem of the conflict graph corresponds to a solution of the MWCMS problem. In this
case, we proved that when the number of input sequences is a constant, MWCMS is polynomial-time solvable. We also demonstrated
that some well-known combinatorial problems can be viewed as special cases of the MWCMS problem. In particular, we presented
theoretical results implied by the MWCMS theory for the minimum weight supersequence problem, the minimum weight superstring
problem, and the longest common subsequence problem.
Two integer programming formulations were presented and a simple yet elegant decomposition heuristic was introduced. The integer
programming instances have proven to be computationally intensive. Consequently, research involving simultaneous column and
row generation and parallel computing will be explored. The heuristic algorithm, introduced herein for multiple sequence alignment,
overcomes the order-dependent drawbacks of many of the existing algorithms, and is capable of returning good sequence alignments
within reasonable computational time. It is able to return the optimal alignment for multiple sequences of length less than
1500 base pairs within 30 minutes. Its algorithmic decomposition nature lends itself naturally for parallel distributed computing,
and we continue to explore its flexibility and scalability in a massive parallel environment. 相似文献
68.
Guangjie Li 《Applicable analysis》2018,97(15):2555-2572
Little seems to be known about stability results on the neutral stochastic function differential equations with Markovian switching driven by G-Brownian (G-NSFDEwMSs). This paper aims at investigating the pth moment exponential stability for G-NSFDEwMSs to fill this gap. Some sufficient conditions on the pth moment exponential stability of the trivial solution are derived by employing the Razumikhin-type method, stochastic analysis, and algebraic inequality technique. Moreover, an example is provided to illustrate the effectiveness of the obtained results. 相似文献
69.
We present 35 open problems on combinatorial, geometric and algebraic aspects of -orbit abstract polytopes. We also present a theory of rooted polytopes that has appeared implicitly in previous work but has not been formalized before. 相似文献
70.
Abdelhadi Es-Sarhir 《Journal of Functional Analysis》2010,259(5):1248-1272
We study regularity properties for invariant measures of semilinear diffusions in a separable Hilbert space. Based on a pathwise estimate for the underlying stochastic convolution, we prove a priori estimates on such invariant measures. As an application, we combine such estimates with a new technique to prove the L1-uniqueness of the induced Kolmogorov operator, defined on a space of cylindrical functions. Finally, examples of stochastic Burgers equations and thin-film growth models are given to illustrate our abstract result. 相似文献