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971.
We derive lower bounds for Lp norms , in the central limit theorem for independent and m–dependent random variables with finite fifth order absolute moments and for independent and m–dependent identically distributed random variables with fourth order moments.  相似文献   
972.
本文研究了单部件、一个修理工组成的可修系统的最优更换问题,假定系统不能修复如新,以系统年龄T为策略,利用几何过程求出了最优的策略T^*,使得系统经长期运行单位时间内期望效益达到最大,并求出了系统经长期运行单位时间内期望效益的显式表达式。在一定条件下证明了T^*的唯一存在性。最后还证明了策略T^*比文献[6]中的策略T^*优。  相似文献   
973.

We characterize the compactness of a subset of compact operators between Banach spaces when the domain space does not have a copy of

  相似文献   

974.

Let be the Weinstein operator on the half space, . Suppose there is a sequence of Borel sets such that a certain tangential projection of onto forms a pairwise disjoint subset of the boundary. Let be a finite test measure on the boundary for a specific non-isotropic Hausdorff measure. The measure is carried back to a measure on a subset of by the projection. We give an upper bound for the Weinstein potential corresponding to the measure in terms of a universal constant and a Weinstein subharmonic function. We use this upper bound to deduce a result concerning tangential behavior of Weinstein potentials at the boundary with the exception of sets on the boundary of vanishing non-isotropic Hausdorff measure.

  相似文献   

975.
We prove the following theorem. Let m and n be any positive integers with mn, and let be a subset of the n-dimensional Euclidean space n . For each i=1, . . . , m, there is a class of subsets M i j of Tn . Assume that for each i=1, . . . , m, that M i j is nonempty and closed for all i, j, and that there exists a real number B(i, j) such that and its jth component xjB(i, j) imply . Then, there exists a partition of {1, . . . , n} such that for all i and We prove this theorem based upon a generalization of a well-known theorem of Birkhoff and von Neumann. Moreover, we apply this theorem to the fair allocation problem of indivisible objects with money and obtain an existence theorem.  相似文献   
976.
We call a sequence (T n ) of measure preserving transformations strongly mixing if tends to P(A)P(B) for arbitrary measurable A, B. We investigate whether one can pass to a suitable subsequence such that almost surely for all (or "many") integrable f.  相似文献   
977.
We characterize the set of functions which can be approximated by polynomials with the following norm

for a big class of weights w0w1, …, wk  相似文献   
978.
The main result of this paper is the following theorem. Suppose thatτ(n) = ∑ d|n l and the arithmetical functionF satisfies the following conditions:
1)  the functionF is multiplicative;
2)  ifF(n) = ∑ d|n f(d), then there exists an α>0 such that the relationf(n)=O(n −α) holds asn→∞.
Then there exist constantsA 1,A 2, andA 3 such that for any fixed \g3\s>0 the following relation holds:
. Moreover, if for any primep the inequality \vbf(p)\vb\s<1 holds and the functionF is strongly multiplicative, thenA 1\s>0. Translated fromMatematicheskie Zametki, Vol. 68, No. 3, pp. 429–438, September, 2000.  相似文献   
979.
The mapping version of Pöschel's theory on differentiable foliation structures of invariant tori is presented and the relevant estimates explicitly in terms of the diophantine constant and the nondegeneracy parameters of frequency maps are given. As a direct application of the main result, a generalization of Moser's small twist theorem to high dimensions is given.  相似文献   
980.
Let X and Y be locally compact Hausdorff spaces and T : C0(X) C0(Y) a ring homomorphism. We completely characterize such homomorphisms and show that if T is R-linear, then T is either C-linear or C-antilinear. In any case T is continuous and there is a continuous map : Y X such that Tf = f o , f C0(X) (if T is C-linear) or (if T is C-antilinear). Thus, extending a result of Mólnar, we also derive the general form of an isometry T.AMS Subject Classification (2000): primary 46J05, 46E25(deceased) Passed away on 24 May 1999.  相似文献   
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