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101.
A. Nowakowski 《Journal of Optimization Theory and Applications》1986,50(1):129-147
In this paper, on the basis of Young's method (Ref. 1), sufficient conditions for a strong relative minimum in an optimal control problem are given. Young's method generalizes geodesic coverings and the simplest Hilbert integral from the standard variational calculus. This paper carries Young's method over to nonparametric problems. 相似文献
102.
关于hilbert-ingham不等式和它的应用 总被引:4,自引:1,他引:4
本文给出(i)hilbert不等式和hilbert-ingham不等式一些有意义的共同改进;(ii)一些fejer-riesz型不等式的改进和(iii)hardy不等式的改进. 相似文献
103.
The multivariate extension of the Cox model proposed by Wei,Lin and Weissfeld in 1989 has been widely used for analyzing multivariate survival data.Under the model assumption,failure times from an individual are assumed to marginally follow their respective proportional hazards regression relation,leaving the joint distribution completely unspecified.This paper presents a simple approach to efficiency improvement through segmentation of stochastic integrals in the marginal estimating equations and incorporation of the limiting covariance structure.It is shown that when partition of the time interval is done at a suitable rate,the resulting estimator is consistent and asymptotically normal.Through the reproducing kernel Hilbert space arising from the covariance function of the limiting Gaussian process,it is also shown that the proposed estimator is asymptotically optimal within a reasonable class of estimators under marginal specification.Simulations are conducted to assess the finite-sample performance of the proposed method. 相似文献
104.
In this paper, we construct a general theory of a priori error estimates for scalar conservation laws by suitably modifying the original Kuznetsov approximation theory. As a first application of this general technique, we show that error estimates for conservation laws can be obtained without having to use explicitly any regularity properties of the approximate solution. Thus, we obtain optimal error estimates for the Engquist-Osher scheme without using the fact (i) that the solution is uniformly bounded, (ii) that the scheme is total variation diminishing, and (iii) that the discrete semigroup associated with the scheme has the -contraction property, which guarantees an upper bound for the modulus of continuity in time of the approximate solution.
105.
S~1×S~1-Borsuk-UlamTheoremonProductSpacesZhongChengkui(钟承奎)(DepartmentofMathematics,LanzhouUniversity,Lanzhou,730000)Abstract:... 相似文献
106.
107.
Let R be a homogeneous ring over an infinite field, IR a homogeneous ideal, and
I an ideal generated by s forms of degrees d
1,...,d
s
so that codim(
:I)s. We give broad conditions for when the Hilbert function of R/
or of R/(
:I) is determined by I and the degrees d
1,...,d
s
. These conditions are expressed in terms of residual intersections of I, culminating in the notion of residually S
2 ideals. We prove that the residually S
2 property is implied by the vanishing of certain Ext modules and deduce that generic projections tend to produce ideals with this property. 相似文献
108.
Einar Steingrímsson 《Journal of Algebraic Combinatorics》2001,14(1):73-84
Let G be a simple graph on d vertices. We define a monomial ideal K in the Stanley-Reisner ring A of the order complex of the Boolean algebra on d atoms. The monomials in K are in one-to-one correspondence with the proper colorings of G. In particular, the Hilbert polynomial of K equals the chromatic polynomial of G.The ideal K is generated by square-free monomials, so A/K is the Stanley-Reisner ring of a simplicial complex C. The h-vector of C is a certain transformation of the tail
T(n) = n
d – (n) of the chromatic polynomial of G. The combinatorial structure of the complex C is described explicitly and it is shown that the Euler characteristic of C equals the number of acyclic orientations of G. 相似文献
109.
We solve a boundary interpolation problem in the reproducing kernel Hilbert space of functions analytic in the unit ball of
with reproducing kernel 1/(1−∑1Nzkwk*). We introduce the notion of Brune factor (or Blaschke–Potapov factor of the third kind) in this setting. 相似文献
110.
非线性抛物组非均匀网格差分解的唯一性和稳定性 总被引:3,自引:1,他引:3
1.引言 1.对一维非线性抛物组,在文献山中已构造一般非均匀网格差分格式,其中差分逼近的组合系数对不同的网格点和不同的网格层可以不同,并且运用不动点原理证明了差分解的存在性和收敛性.在非均匀网格差分格式中差分逼近的组合系数为常数的情形,文献[2]证明了具有有界二阶差商的离散向量解的存在性、唯一性和稳定性.本文将对文献[1]中构造的一般非均匀网格差分格式,证明所得到的差分解的唯一性和稳定性. 考虑如下非线性抛物组其中是未知的m-维向量函数是给定的矩阵函数,j(x,t,u,p)。是给定的m-维向量函数… 相似文献