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61.
研究了具有非局部时滞的扩散Nicholson苍蝇方程,其中时滞由一个定义在所有过去时间和整个一维空间区域上的积分卷积表示.当时滞核是强生成核时,根据线性链式技巧和几何奇异扰动理论,获得了小时滞时波前解的存在性. 相似文献
62.
This paper is the first of two papers on the time discretizationof the equation ut + t 0 ß (t s) Au (s) ds= 0, t > 0, u (0) = u0, where A is a self-adjoint denselydefined linear operator on a Hilbert space H with a completeeigensystem {m, m}m = 1, and ß (t) is completely monotonicand locally integrable, but not constant. The equation is discretizedin time using first-order differences in combination with order-oneconvolution quadrature. The stability properties of the timediscretization are derived in the l1t (0, ; H) norm. 相似文献
63.
In terms of Berezin symbols, we give several criteria for operators to belong to the Schatten--von Neumann classes
. In particular, for functions of model operators, we give a complete answer to a question posed by Nordgren and Rosenthal. 相似文献
64.
Bump Daniel Diaconis Persi Keller Joseph B. 《Mathematical Physics, Analysis and Geometry》2002,5(2):101-123
Let M be a unitary matrix with eigenvalues t
j
, and let f be a function on the unit circle. Define X
f
(M)=f(t
j
). We derive exact and asymptotic formulae for the covariance of X
f
and X
g
with respect to the measures |(M)|2dM where dM is Haar measure and an irreducible character. The asymptotic results include an analysis of the Fejér kernel which may be of independent interest. 相似文献
65.
A stability theorem of the Bergman kernel and completeness of the Bergman metric have been proved on a type of non-smooth
pseudoconvex domains defined in the following way:D = {z∈U|r(z)} <whereU is a neighbourhood of
andr is a continuous plurisubharmonic function onU. A continuity principle of the Bergman Kernel for pseudoconvex domains with Lipschitz boundary is also given, which answers
a problem of Boas. 相似文献
66.
Let X
1
,...,X
n
be a random sample drawn from distribution function F(x) with density function f(x) and suppose we want to estimate X(x). It is already shown that kernel estimator of F(x) is better than usual empirical distribution function in the sense of mean integrated squared error. In this paper we derive integrated squared error of kernel estimator and compare the error with that of the empirical distribution function. It is shown that the superiority of kernel estimators is not necessarily true in the sense of integrated squared error. 相似文献
67.
吴嘎日迪 《应用泛函分析学报》2002,(3)
讨论了由非退化的全正核K(x,y)和具有特定性质的函数系{ki(x)}ri=1所确定的某一函数类 (?)∞在Orlicz空间内的n-K宽度,n-G宽度,n-L宽度的精确估计问题. 相似文献
68.
A note on the nucleolus and the kernel of the assignment game 总被引:1,自引:0,他引:1
There exist coalitional games with transferable utility which have the same core but different nucleoli. We show that this cannot happen in the case of assignment games. Whenever two assignment games have the same core, their nucleoli also coincide. To show this, we prove that the nucleolus of an assignment game coincides with that of its buyer–seller exact representative.I am grateful to C. Rafels and to the referees for their comments. Institutional support from research grants BEC 2002-00642 and SGR2001–0029 is also acknowledged. 相似文献
69.
We compute the 2-rank of the wild kernel WK2(F) of a number field by constructing a 2-class group ad hoc. The main result generalizes in the more intricate case the canonical isomorphism established for odd primes under the assumption in a previous article (cf. (Acta. Arith. 67 (1994) 335; Math. Z. 238 (2001) 335)). It involves a criterium of triviality for the 2-part of the wild kernel of Galois number fields and, in the particular case of quadratic fields, it leads to a logarithmic interpretation of the diophantine conditions obtained by other authors. 相似文献
70.
New classes of domains with explicit Bergman kernel 总被引:9,自引:1,他引:8
Roos GUY 《中国科学A辑(英文版)》2004,47(3):352-371
We introduce two classes of egg type domains, built on general bounded sym-metric domains, for which we obtain the Bergman kernel in explicit formulas. As an aux-iliary tool, we compute the integral of complex powers of the generic norm on a boundedsymmetric domains using the well-known integral of Selberg. This generalizes matrix in-tegrals of Hua and leads to a special polynomial with integer or half-integer coefficientsattached to each irreducible bounded symmetric domain. 相似文献