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161.
The Poincaré series of the algebra of -invariants of m-tuples of 2×2 matrices is presented both as a rational function and as a series of Schur functions. We show that this algebra of invariants is generated by the determinants, the mixed discriminants and the discriminants of 2×2 matrices. Consequences on invariants of three-dimensional matrices of the shape 2×2×m are discussed. For arbitrary n2, we prove an explicit functional equation for the Poincaré series of the -invariants of m-tuples of n×n matrices.  相似文献   
162.
The influence of the use of the generalized Hermite polynomial on the Hermite-based lattice Bofiz- mann (LB) construction approach, lattice sets, the thermal weights, moments and the equilibrium distribution function (EDF) are addressed. A new moment system is proposed. The theoretical possibility to obtain a unique high-order Hermite-based singel relaxation time LB model capable to exactly inatch some first hydrodynamic inoments thermally i) on-Cartesian lattice, ii) with thermal weights in the EDF, iii) whilst the highest possible hydrodynamic moments that are exactly reatched are obtained with the shortest on-Cartesian lattiee sets with some fixed real-valued temperatures, is also analyzed.  相似文献   
163.
刘德峰 《数学季刊》2001,16(3):34-41
在本文中,我们研究斯坦伯格问题,发展了罚函数法。  相似文献   
164.
In this paper, we consider the problem of asymptotically minimax testing ofr≥2 simple hypotheses when a general stochastic process is observed. We establish general conditions for the exponential decrease of maximal probability errors of minimax tests as the number of observations increases. At the present time, similar results for testing several multinomial schemes were obtained by Salihov [8]. Similar results for testing two simple hypotheses were obtained in [5]. In the proofs of the main results, we use the theory of large deviations ([3], [2]). In Sec. 1, the main result is proved. In Secs. 2–4, we analyze the i.i.d. case, nonhomogeneous Poisson processes, and renewal processes as examples. Published in Lietuvos Matematikos Rinkinys, Vol. 40, No. 3, pp. 313–320, July–September, 2000.  相似文献   
165.
Classes of subsets of positive integers based on the notion of selector functions similar to the Jockusch selector of a semirecursive set are studied.  相似文献   
166.
Summary We consider distributions with densities of the formf(μ′x) andf(‖x v ‖) where μ andx are unit vectors inR q and ‖x v ‖ is the norm of the part ofx in somes dimensional subspaceV ofR q . For several loss functions, optimal Bayesian and Pitman estimators of μ andV are given. When uniform priors are used, these estimators are identical. Then the infinitesimal robustness characteristics of several special cases of these estimators are calculated.  相似文献   
167.
This paper presents a successive quadratic programming algorithm for solving general nonlinear programming problems. In order to avoid the Maratos effect, direction-finding subproblems are derived by modifying the second-order approximations to both objective and constraint functions of the problem. We prove that the algorithm possesses global and superlinear convergence properties.This work was supported in part by a Scientific Research Grant-in-Aid from the Ministry of Education, Science and Culture, Japan.  相似文献   
168.
求解交通均衡配流问题的新算法   总被引:1,自引:0,他引:1  
给出了一个求解交通均衡配流问题的新算法,证明了新算法的收敛性,并在小型交通网络上进行了初步的数值试验.  相似文献   
169.
Suppose thatB R d is a ball of radiusR in ℂ d and σ is the standard measure on the unit sphere in ℂ d . ForR>1, 1≤p≤∞, and for the natural numbersl, d, byH R 0 (l, p, d) we denote the class of functionsf holomorphic inB R d and such that in the homogeneous polynomial expansion of the firstl summands the zero and radial derivatives of orderl belong to the closed unit ball of the Hardy spaceH p (B R d ). In this paper an asymptotic formula for the ε-entropy of the classH R 0 (l, p, d) in the spacesL p (σ), 1≤p<∞, and is obtained. Translated fromMatematicheskie Zametki, Vol. 68, No. 2, pp. 286–293, August, 2000.  相似文献   
170.
Let Xn,n 1,be a sequence of independent random variables satisfying P(Xn = O) = 1 - P(Xn = an) = 1 - 1/pn,where an,n 1,is a sequence of real numbers,andpn isthenthprime,setFN(x)=P(N∑Xnn=1 x).The authors investigate a conjecture of Erdos in probabilistic number theory and show that in order for the sequence FN to be weakly convergent,it is both sufficient and necessary that there exist three numbers x0 and x1 < x2 such that limsup(FN(x2) -FN(x1)) > 0 holds,and Lo =N→∞ lim FN(x0) exists.Moreover,the authors point ont that they can also obtain the same N→∞ result in the weakened case of liminfP(Xn = 0) > 0.n→∞  相似文献   
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