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51.
积域上一类奇异积分算子的L~p有界性 总被引:1,自引:0,他引:1
本文证明,对于Ω∈(1)∩L(log~+L)~2(S~(n-1)×S~(m-1)),h(r,s)∈L~∞(R_+~1×R_+~1)和P_(N_1),P_(N_2)∈(2),带粗糙核的奇异积分算子为L~p有界。 相似文献
52.
Chin-Tsang Chiang Mei-Cheng Wang 《Annals of the Institute of Statistical Mathematics》2004,56(1):87-100
This paper proposes kernel estimation of the occurrence rate function for recurrent event data with informative censoring.
An informative censoring model is considered with assumptions made on the joint distribution of the recurrent event process
and the censoring time without modeling the censoring distribution. Under the validity of the informative censoring model,
we also show that an estimator based on the assumption of independent censoring becomes inappropriate and is generally asymptotically
biased. To investigate the asymptotic properties of the proposed estimator, the explicit form of its asymptotic mean squared
risk and the asymptotic normality are derived. Meanwhile, the empirical consistent smoothing estimator for the variance function
of the estimator is suggested. The performance of the estimators are also studied through Monte Carlo simulations. An epidemiological
example of intravenous drug user data is used to show the influence of informative censoring in the estimation of the occurrence
rate functions for inpatient cares over time. 相似文献
53.
S. C. Joshi M. P. Singh V. P. Pandey B. S. Rajput 《International Journal of Theoretical Physics》2002,41(6):1107-1125
In four-dimensional N = 4 supersymmetric gauge theory, we obtain an exact metric on the moduli space of quantum vacua and analyze the spectra of BPS states in weak as well as in strong coupling regions. Identifying the hypermultiplet of the dyonic state as a string stretched between D3-brane probe and a 7-brane, we demonstrate that the two hypermultiplets, which become massless at two singularities in supersymmetric theory, correspond to open strings beginning on the D3-brane and ending on the respective 7-brane. 相似文献
54.
New classes of domains with explicit Bergman kernel 总被引:8,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
55.
Nasser-eddine Tatar 《Journal of Mathematical Analysis and Applications》2004,295(2):303-314
We consider the fractional differential equation
56.
X. R. Ma 《Proceedings of the American Mathematical Society》2005,133(11):3179-3189
We present a necessary and sufficient condition for two matrices given by two bivariate functions to be inverse to each other with certainty in the cases of Krattenthaler formula and Warnaar's elliptic matrix inversion. Immediate consequences of our result are some known functions and a constructive approach to derive new matrix inversions from known ones.
57.
Jerzy Browkin. 《Mathematics of Computation》2005,74(250):967-999
There are many results describing the structure of the tame kernels of algebraic number fields and relating them to the class numbers of appropriate fields. In the present paper we give some explicit results on tame kernels of cubic cyclic fields. Table 1 collects the results of computations of the structure of the tame kernel for all cubic fields with only one ramified prime
In particular, we investigate the structure of the 7-primary and 13-primary parts of the tame kernels. The theoretical tools we develop, based on reflection theorems and singular primary units, enable the determination of the structure even of 7-primary and 13-primary parts of the tame kernels for all fields as above. The results are given in Tables 2 and 3.
58.
混合互补判断矩阵一致性研究 总被引:3,自引:0,他引:3
给出混合互补判断矩阵一致性的定义和判别加性一致性的方法.定义了核算子、核矩阵,对带有精确数、三角模糊数和梯形模糊数的混合互补判断矩阵给出基于核矩阵的一致性调整方法,调整量可以是精确数也可以是模糊数.最后给出一个应用实例. 相似文献
59.
The rank of a q-ary code C is the dimension of the subspace spanned by C. The kernel of a q-ary code C of length n can be defined as the set of all translations leaving C invariant. Some relations between the rank and the dimension of the kernel of q-ary 1-perfect codes, over
as well as over the prime field
, are established. Q-ary 1-perfect codes of length n=(qm − 1)/(q − 1) with different kernel dimensions using switching constructions are constructed and some upper and lower bounds for the dimension of the kernel, once the rank is given, are established.Communicated by: I.F. Blake 相似文献
60.
In this paper, we obtain the general solution for the continuous Smoluchowski equation in the multicomponent case with a product kernel as a series expansion. The solution of the problem involves the Laplace transform in several dimensions. We obtain a nonlinear partial differential equation (PDE) of the advective kind generalizing the one previously given by other authors for the mono-component case.As in its relative mono-component case, gelation is produced at some point, the conditions for its occurrence being the same as those for the mono-component case, though substituting a sum of derivatives by a derivative in the Laplace transform field. We demonstrate that for a multicomponent particle size distribution (PSD) of multiplicative form, it is sufficient for one of the marginal PSDs to generate instantaneous gelation for the occurrence of instantaneous gelation in the multicomponent PSD.The general solution is applied to several specific cases, a discrete case that recovers a previously known solution, and another two continuous cases which can be used to check numerical methods designed to directly solve the Smoluchowski equation in more general cases.We have compared the solutions for the multicomponent PSD for constant, additive and product kernels and we conjecture about the relation existing between the functional forms for the solutions both in the mono-component and the multicomponent case.Finally, we have analysed the shape of the solutions for multicomponent PSD for constant, additive and product kernels for very small masses of components, obtaining a qualitatively different behaviour for the product kernel. This has effects in the mixing state of the sol phase as time passes. 相似文献