共查询到20条相似文献,搜索用时 31 毫秒
1.
Lian-Xi Ku 《Southeast Asian Bulletin of Mathematics》2000,24(3):375-382
In this note, we prove that, for Robins boundary value problem, a unique solution exists if fx(t, x, x), fx(t, x, x), (t), and (t) are continuous, and fx -(t), fx -(t), 4(t) 2 + 2(t) ++ 2(t), and 4(t) 2 + 2(t) + 2(t).AMS Subject Classification (2000) 34B15 相似文献
2.
U. Goginava 《Analysis Mathematica》2000,26(3):209-226
In this paper we prove that if f C
(0, 1
N
) and the function f is of bounded partial variation, then the N-dimensional Walsh-Fourier series of the function f is uniformly (C,–) summable (1 +...+
N
< 1,
i
> 0, i = 1,...,N) in the sense of Pringsheim. If 1 +...+
N
= 1,
i
> 0, i = 1,2,...,N, then there exists a continuous function f
0 of bounded partial variation on [0, 1]
N
such that the Cesàro (C,–) means
m
–
(f0,Õ) of the N-dimensional Walsh-Fourier series of f
0 diverge over cubes. 相似文献
3.
Toshio Honda 《Annals of the Institute of Statistical Mathematics》2000,52(3):459-470
Let (Xi,Y
i) be a set of observations form a stationary -mixing process and (x) be the conditional -th quantile of Y given X = x. Several authors considered nonparametric estimation of (x) in the i.i.d. setting. Assuming the smoothness of FF(x), we estimate it by local polynomial fitting and prove the asymptotic normality and the uniform convergence. 相似文献
4.
Summary For the Fisher-Wright-Haldane selection model with fitness parametersf
ij
=1+
i
ij
(
i
–1) a complete global analysis is performed.
Zusammenfassung Für das Fisher-Wright-Haldane-Selektionsmodell mit den Fitneßparameternf ij =1+ i ij ( i –1) wird eine vollständige globale Analyse, durchgeführt.相似文献
5.
Takaaki Shimura 《Acta Appl Math》2000,63(1-3):411-432
A distribution is said to have regularly varying tail with index – (0) if lim
x(kx,)/(x,)=k
– for each k>0. Let X and Y be independent positive random variables with distributions and , respecitvely. The distribution of product XY is called Mellin–Stieltjes convolution (MS convolution) of and . It is known that D() (the class of distributions on (0,) that have regularly varying tails with index –) is closed under MS convolution. This paper deals with decomposition problem of distributions in D() related to MS convolution. A representation of a regularly varying function F of the following form is investigated: F(x)=
k=0
n–1
b
k
f(a
k
x), where f is a measurable function and a and b
k
(k=1,...,n–1) are real constants. A criterion is given for these constants in order that f be regularly varying. This criterion is applicable to show that there exist two distributions and such that neither nor belongs to D() (>0) and their MS convolution belongs to D(). 相似文献
6.
G. V. Kuz'mina 《Journal of Mathematical Sciences》1978,10(2):241-256
We obtain a complete solution of the problem of the maximum of the fourth diameter in the family of continua with capacity 1. Let E(o, ei, e–i). 0<2, be a continuum of minimum capacity containing the points o, ei, e–i; H(=cap E(o, ei, e–i). Let C() be the common point of three analytic arcs which form E(o, ei, e–i). One shows that the indicated maximum is realized by the continuum ={z:H(0)z
2E(o, ei, e–i)} where
0, o<02, is a solution of the equation. Any other extremal continuum of the gives problem is an image of under the mappingz ei
z+C ( is a real and C is a complex constant). One finds the value of the required maximum. The paper contains a brief exposition of the proof of this result.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 59, pp. 60–79, 1976. 相似文献
7.
M. N. El Tarazi 《BIT Numerical Mathematics》1990,30(3):484-489
The interpolation problem at uniform mesh points of a quadratic splines(x
i)=f
i,i=0, 1,...,N ands(x
0)=f0 is considered. It is known that s–f=O(h
3) and s–f=O(h
2), whereh is the step size, and that these orders cannot be improved. Contrary to recently published results we prove that superconvergence cannot occur for any particular point independent off other than mesh points wheres=f by assumption. Best error bounds for some compound formulae approximatingf
i
andf
i
(3)
are also derived. 相似文献
8.
Let F(x) = xn+1 xn-1+2 xn-2+ ··· +n be a polynomial with complex coefficients, and suppose we are given a partition (1,...,r) of n. It is a classical problem to determine explicit algebraic conditions on the i so that F may have roots with multiplicities 1,...,r. We give an invariant theoretic solution to this problem, to wit, we exhibit a set of covariants of F whose vanishing is a necessary and sufficient condition. The construction of such covariants is combinatorial, and involves associating a set of graphs on n vertices (called decisive graphs) to each .Received: 28 September 2003 相似文献
9.
Using the well known properties of thes-stage implicit Runge-Kutta methods for first order differential equations, single step methods of arbitrary order can be obtained for the direct integration of the general second order initial value problemsy=f(x, y, y),y(x
o)=y
o,y(x
o)=y
o. These methods when applied to the test equationy+2y+
2
y=0, ,0, +>0, are superstable with the exception of a finite number of isolated values ofh. These methods can be successfully used for solving singular perturbation problems for which f/y and/or f/y are negative and large. Numerical results demonstrate the efficiency of these methods. 相似文献
10.
Gerald Beer 《Monatshefte für Mathematik》1993,115(4):281-290
LetX be a Banach space, and let {f
i:iI} be a family of proper lower semicontinuous convex functions defined onX, each of whose epigraphs meets a fixed bound subset ofX×. We say that {f
i:iI} is uniformly linearly minorized if there exists a positive scalar such that for alliI andxX, we havef
i(x)–(1+x). We present two very different characterizations of uniform linear minorization for such a family. Using one of these, we show that either strong or weak epi-convergence of a sequence of convex functions at some point in the effective domain of the limit implies, uniform linear minorization for the entire sequence.With 1 Figure 相似文献
11.
Peter Hellekalek 《Monatshefte für Mathematik》1992,114(3-4):199-208
Leta be irrational and letf:[0,1] be Riemann-integrable with integral zero. Letf
n
(x) denote the Weyl sumf
n
(x):=
k=0
n–1
f({x
k>}),x/[0,1[,n. We prove criteria for the boundedness of the sequence (f
n
)
n1 and discuss the relation of this question to irregularities of the distribution of sequences. 相似文献
12.
S. V. Solov'ev 《Journal of Mathematical Sciences》1982,20(4):2367-2369
We consider the (&, )-fragment of the intuitionistic propositional calculus. It is proved that under the standard transformation of a Gentzen derivation into a natural derivation(), the length of (())22·length(
). There is constructed a sequence of Gentzen derivations of length i, for which the length of ((
i))21/3·length(i), which shows that the upper bound obtained is not too weak.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 88, pp. 192–196, 1979. 相似文献
13.
Wilhelm Niethammer 《Numerische Mathematik》1980,34(3):271-283
Summary A nonlinear generalizationÊ
z
of Euler's series transformation is compared with the (linear) Euler-Knopp transformationE
z
and a twoparametric methodE
. It is shown how to applyE
orE
, to compute the valuef(zo) of a functionf from the power series at 0 iff is holomorphic in a half plane or in the cut plane. BothE
andE
, are superior toÊ
z
. A compact recursive algorithm is given for computingE
andE
,. 相似文献
14.
The generalized order complementarity problem 总被引:1,自引:0,他引:1
Given an ordered Banach Space (E,K) andm functionsf
1,f
2,...,f
m:EE, the generalized order complementarity problem associated with {f
i} andK is to findx
0K such thatf
i(x
0)K,i=1,...,m, and (x
0,f
1(x
0),...,f
m(x
0))=0. The problem is shown to be equivalent to several fixed-point problems and equivalent to the order complementarity problem studied by Borwein and Dempster and by Isac. Existence and uniqueness of solutions and least-element theory are shown in the spacesC(, ) andL
p(, ). For general locally convex spaces, least-element theory is derived, existence is proved, and an algorithm for computing a solution is presented. Applications to the mixed lubrication theory of fluid mechanics are described. 相似文献
15.
We construct -framed Kripke models of i1 and i1 non of whose worlds satisfies xy(x=2yx=2y+1) and x,yzExp(x, y, z) respectively. This will enable us to show that i1 does not prove ¬¬xy(x=2yx=2y+1) and i1 does not prove ¬¬x, yzExp(x, y, z). Therefore, i1¬¬lop and i1¬¬i1. We also prove that HAl1 and present some remarks about i2.
Mathematics Subject Classification (2000):03F30, 03F55, 03H15. 相似文献
16.
In the present paper we shall consider an application of simple non-polynomial splines to a numerical solution of a weakly singular two-point boundary value problem:x
–
(x
y)=f(x,y), (0<x1) subject toy(0)=0,y(1)=c
1(1) ory(0)=c
2,y(1)=c
3(0<<1). Our collocation method gives a continuously differentiable approximation and isO(h
2)-convergent. 相似文献
17.
E. Bolthausen 《Probability Theory and Related Fields》1982,60(3):283-289
Summary Let 0, 1,... be a stationary Harris recurrent Markov chain with state space (E,), and let f E IR, X
i=f(i). It is known that the sequence X
i, i0, is strongly mixing, i.e. (n)>0 where (n) are the strong (or Rosenblatt) mixing coefficients. If (n) decreases at a sufficiently fast rate and f is suitable, then a central limit holds for the partial sums
. The present paper gives conditions in order that the convergence rates are O(n
–1/2). 相似文献
18.
The following results are obtained: If >0, 2,
[3, 4], andf is a nondecreasing (convex) function on [–1, 1] such thatE
n
(f) n
– for any n>, then E
n
(1)
(f)Cn
– (E
n
(2)
(f)Cn
–) for n>, where C=C(), En(f) is the best uniform approximation of a continuous function by polynomials of degree (n–1), and E
n
(1)
(f) (E
n
(2)
(f)) are the best monotone and convex approximations, respectively. For =2 ( [3, 4]), this result is not true.Published in Ukrainskii Matematicheskii Zhurnal, Vol. 46, No. 9, pp. 1266–1270, September, 1994. 相似文献
19.
K. V. Shakhbazyan 《Journal of Mathematical Sciences》1985,29(6):1677-1699
The solution of the following problems is offered. Suppose a multiset J (¦J¦=p) is given. For each pair of elements and J, a number 1 P is given. Moreover, if 1 < x<p then x is undefined. If x=1, then x=p. Problem 1. Find the permutation 1...F of elements of the multiset J satisfying the following conditions. Let i, i=. If i,j < x, thenj <i. If i,j > x, then i<j. Such a permutation is called a PC-schedule. Problem 2. Find a PC-schedule in which the following property holds: if i < x < j, i=, j=, then. Such a PC-schedule is called an SC-schedule. The conditions under which these problems have solutions are studied. For their solution an algorithm of shifts is used with the complexity O(¦B(J)¦2¦J¦).Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 124, pp. 44–72, 1983. 相似文献
20.
F. A. Sukochev 《Integral Equations and Operator Theory》1996,26(1):102-124
If is a surjective isometry of the separable symmetric operator spaceE(M, ) associated with the approximately finite-dimensional semifinite factorM and if ·
E(M,)
is not proportional to ·
L
2, then there exist a unitary operatorUM and a Jordan automorphismJ ofM such that(x)=UJ(x) for allxME(M, ). We characterize also surjective isometries of vector-valued symmetric spacesF((0, 1), E(M, )).Research supported by the Australian Research Council 相似文献