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161.
For each integer , we give a distinct closed model category structure to the category of pointed spaces such that the corresponding localized category is equivalent to the standard homotopy category of -connected CW-complexes. The structure of closed model category given by Quillen to is based on maps which induce isomorphisms on all homotopy group functors and for any choice of base point. For each , the closed model category structure given here takes as weak equivalences those maps that for the given base point induce isomorphisms on for .

  相似文献   

162.
This paper establishes a criterion for whether a -dimensional random walk on the integer lattice visits a space-time subset infinitely often or not. It is a precise analogue of Wiener's test for regularity of a boundary point with respect to the classical Dirichlet problem. The test obtained is applied to strengthen the harder half of Kolmogorov's test for the random walk.

  相似文献   

163.
Carleson measure characterization of Bloch functions   总被引:1,自引:0,他引:1  
We give several equivalences of Bloch functions and little Bloch functions. Using these results we obtain the generalized Carleson measure characterization of Bloch functions and the generalized vanishing Carleson measure characterization of little Bloch functions, that is,f B if and only if |D f(z)| p (1-|z|2)p-1 dm(z) is a generalized Carleson measure;f B 0 if and only if |D f(z)| p (1-|z|2)p-1 dm(z) is a generalized vanishing Carleson measure, whereD f( > 0) is the fractional derivative of analytic functionf of order, m denotes the normalised Lebesgue measure.Supported partly by the Young Teacher Natural Science Foundation of Shandong Province.  相似文献   
164.
A family of J of open subsets of the real line is called an ω-cover of a set X iff every finite subset of X is contained in an element of J. A set of reals X is a γ-set iff for every ω-cover J of X there exists 〈Dn: n < ω〉? Jω such that
X?nm > n Dm.
In this paper we show that assuming Martin's axiom there is a γ-set X of cardinality the continuum.  相似文献   
165.
Two sufficient criteria for the convergence of the Rayleigh-Ritz Method (RRM) with respect to the eigenvalues (E-convergence) of non-relativistic electronic Hamiltonians of molecules are discussed and compared. Moreover, a necessary and sufficient criterion is given. By example (Sect. 9) it is shown that the L 2-completeness of the basis is not sufficient to guarantee E-convergence. The convergence of the wave functions in different norms (-convergence) is also investigated. In particular, sufficient conditions for the one-particle basis functions (orbitals) are given, such that a CI calculation in this basis is both E- and -convergent.  相似文献   
166.
Let X be an abstract set and L a lattice of subsets of X. To each lattice regular measure µ, we associate two induced measures and on suitable lattices of the Wallman space IR(L) and another measure µ on the spaceIR(L). We will investigate the reflection of smoothness properties of p onto , and µ; and try to set some new criterion for repleteness and measure repleteness.  相似文献   
167.
We give a necessary and sufficient condition for the uniformly non-l n (1) property of Musielak-Orlicz sequence spacesl Φ generated by a sequence Φ=(ϕn:n⩾l) of finite Orlicz functions such that for eachn∈ℕ. As a result, forn 0⩾2, there exist spacesl Φ which are only uniformly non-l n (1) fornn 0. Moreover we obtain a characterization of uniformly non-l n (1) and reflexive Orlicz sequence spaces over a wide class of purely atomic measures and of uniformly non-l n (1) Nakano sequence spaces. This extends a result of Luxemburg in [19]. Submitted in memory of Professor W. Orlicz  相似文献   
168.
We study wild embeddings of S 1 in S n which are tame in a sense introduced by Quinn. We show that if is a finitely presented group with H 1()=H 2()=0, then any finiteness obstruction K 0() can be realized on the complement of such an embedded S 1. We also realize trivially symmetric K –1() obstructions on the complements of such embeddings. For trivially symmetric , the embeddings constructed are shown to be isotopy homogeneous.  相似文献   
169.
Consider a (complex) Banach spaceX, such thatX CO, and vectors(X i ) i ofX. Consider an independent standard normal sequence(g i ) i . Then if anX-valued random Fourier series |k| n e ikt g k x k satisfies
  相似文献   
170.
The convergence (X n, Yn)0 is investigated and characterized for probability metrics which metrize convergence in distribution or in probability. Some related metrics are also considered.  相似文献   
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