共查询到20条相似文献,搜索用时 15 毫秒
1.
Melvin Hausner 《Combinatorica》1985,5(3):215-225
Ifμ is a positive measure, andA
2, ...,A
n
are measurable sets, the sequencesS
0, ...,S
n
andP
[0], ...,P
[n] are related by the inclusion-exclusion equalities. Inequalities among theS
i
are based on the obviousP
[k]≧0. Letting
=the average average measure of the intersection ofk of the setsA
i
, it is shown that (−1)
k
Δ
k
M
i
≧0 fori+k≦n. The casek=1 yields Fréchet’s inequalities, andk=2 yields Gumbel’s and K. L. Chung’s inequalities. Generalizations are given involvingk-th order divided differences. Using convexity arguments, it is shown that forS
0=1,
whenS
1≧N−1, and
for 1≦k<N≦n andv=0, 1, .... Asymptotic results asn → ∞ are obtained. In particular it is shown that for fixedN,
for all sequencesM
0, ...,M
n
of sufficiently large length if and only if
for 0<t<1. 相似文献
2.
Achiya Dax 《BIT Numerical Mathematics》1997,37(3):600-622
This paper presents a proximal point algorithm for solving discretel
∞ approximation problems of the form minimize ∥Ax−b∥∞. Let ε∞ be a preassigned positive constant and let ε
l
,l = 0,1,2,... be a sequence of positive real numbers such that 0 < ε
l
< ε∞. Then, starting from an arbitrary pointz
0, the proposed method generates a sequence of points z
l
,l= 0,1,2,..., via the rule
. One feature that characterizes this algorithm is its finite termination property. That is, a solution is reached within
a finite number of iterations. The smaller are the numbers ε
l
the smaller is the number of iterations. In fact, if ε
0
is sufficiently small then z1 solves the original minimax problem.
The practical value of the proposed iteration depends on the availability of an efficient code for solving a regularized minimax
problem of the form minimize
where ∈ is a given positive constant. It is shown that the dual of this problem has the form maximize
, and ify solves the dual thenx=A
T
y solves the primal. The simple structure of the dual enables us to apply a wide range of methods. In this paper we design
and analyze a row relaxation method which is suitable for solving large sparse problems. Numerical experiments illustrate
the feasibility of our ideas. 相似文献
3.
A. I. Pavlov 《Mathematical Notes》2000,68(3):370-377
The main result of this paper is the following theorem. Suppose thatτ(n) = ∑
d|n
l and the arithmetical functionF satisfies the following conditions:
Then there exist constantsA
1,A
2, andA
3 such that for any fixed \g3\s>0 the following relation holds:
. Moreover, if for any primep the inequality \vbf(p)\vb\s<1 holds and the functionF is strongly multiplicative, thenA
1\s>0.
Translated fromMatematicheskie Zametki, Vol. 68, No. 3, pp. 429–438, September, 2000. 相似文献
1) | the functionF is multiplicative; |
2) | ifF(n) = ∑ d|n f(d), then there exists an α>0 such that the relationf(n)=O(n −α) holds asn→∞. |
4.
Let A
0, ... , A
n−1 be operators on a separable complex Hilbert space , and let α0,..., α
n−1 be positive real numbers such that 1. We prove that for every unitarily invariant norm,
for 2 ≤ p < ∞, and the reverse inequality holds for 0 < p ≤ 2. Moreover, we prove that if ω0,..., ω
n−1 are the n roots of unity with ω
j
= e
2πij/n
, 0 ≤ j ≤ n − 1, then for every unitarily invariant norm,
for 2 ≤ p < ∞, and the reverse inequalities hold for 0 < p ≤ 2. These inequalities, which involve n-tuples of operators, lead to natural generalizations and refinements of some of the classical Clarkson inequalities in the
Schatten p-norms. Extensions of these inequalities to certain convex and concave functions, including the power functions, are olso
optained.
相似文献
5.
Jugal Ghorai 《Annals of the Institute of Statistical Mathematics》1980,32(1):341-350
LetX
1,...,X
n
be i.i.d. random variable with a common densityf. Let
be an estimate off(x) based on a complete orthonormal basis {φ
k
:k≧0} ofL
2[a, b]. A Martingale central limit theorem is used to show that
, where
and
. 相似文献
6.
Let α be a rational-valued set-function on then-element sexX i.e. α(B) εQ for everyB ⫅X. We say that α defines a 0-configuration with respect toA⫅2
x
if for everyA εA we have
α(B)=0. The 0-configurations form a vector space of dimension 2
n
− |A| (Theorem 1). Let 0 ≦t<k ≦n and letA={A ⫅X: |A| ≦t}. We show that in this case the 0-configurations satisfying α(B)=0 for |B|>k form a vector space of dimension
, we exhibit a basis for this space (Theorem 4). Also a result of Frankl, Wilson [3] is strengthened (Theorem 6). 相似文献
7.
M. Rudelson 《Israel Journal of Mathematics》1999,111(1):143-155
Lett≥1 and letn, M be natural numbers,n<M. Leta=(a
i,j
) be ann xM matrix whose rows are orthonormal. Suppose that the ℓ2-norms of the columns ofA are uniformly bounded. Namely, for allj
Using majorizing measure estimates we prove that for every ε>0 there exists, a setI ⊃ {1,…,M} of cardinality at most
such that the matrix
, whereA
I
=(a
i,j
)
j∈I
, acts as a (1+ε)-isomorphism from ℓ
2
n
into
.
Research supported in part by a grant of the US-Israel BSF. Part of this research was performed when the author held a postdoctoral
position at MSRI. Research at MSRI was supported in part by NSF grant DMS-9022140. 相似文献
8.
There are reverse inequalities for square functions of differences arising in ergodic theory and differentiation of functions.
For example, it is shown that if An is the usual average in ergodic theory, and (nk∶k=1,2,3,...) is an increasing lacunary sequence with no non-trivial common divisor, then one has for any p, 1<p<∞, there
is a constant Cp such that for all f∃ Lp(X),
. 相似文献
9.
Cvetan Jardas Josip Peari Nikola Sarapa 《Rendiconti del Circolo Matematico di Palermo》1998,47(3):481-492
In this paper we study the problem of convergence in the weak and the vague topology of the sequence
where μ and ν are probability measures on locally compact commutative semigroupS andA
n
=[a
ij
(n)
(i, j, n ɛ N) are double stochastic matrices satisfying some additional conditions. Our results generalize the results in [9]. Theorem
1 also holds if we make some changes on the topological assumptions onS, i.e. if we suppose thatS is a polish space. 相似文献
10.
11.
A general result on precise asymptotics for linear processes of positively associated sequences 总被引:2,自引:0,他引:2
Let {εt; t ∈ Z^+} be a strictly stationary sequence of associated random variables with mean zeros, let 0〈Eε1^2〈∞ and σ^2=Eε1^2+1∑j=2^∞ Eε1εj with 0〈σ^2〈∞.{aj;j∈Z^+} is a sequence of real numbers satisfying ∑j=0^∞|aj|〈∞.Define a linear process Xt=∑j=0^∞ ajεt-j,t≥1,and Sn=∑t=1^n Xt,n≥1.Assume that E|ε1|^2+δ′〈 for some δ′〉0 and μ(n)=O(n^-ρ) for some ρ〉0.This paper achieves a general law of precise asymptotics for {Sn}. 相似文献
12.
For multiplicative functions ƒ(n), let the following conditions be satisfied: ƒ(n)≥0 ƒ(p
r)≤A
r,A>0, and for anyε>0 there exist constants
,α>0 such that
and Σ
p≤x
ƒ(p) lnp≥αx. For such functions, the following relation is proved:
. Hereτ(n) is the number of divisors ofn andC(ƒ) is a constant.
Translated fromMatematicheskie Zametki, Vol. 64, No. 3, pp. 443–456, September, 1998.
The work of the first author was supported by the Russian Foundation for Basic Research. 相似文献
13.
M. A. Nudelman 《Integral Equations and Operator Theory》2007,58(2):273-299
Let
I
m
is the identity matrix of order m. Let W(λ) be an entire matrix valued function of order 2m, W(0) = I
2m
, the values of W(λ) are j
mm
-unitary at the imaginary axis and strictly j
mm
-expansive in the open right half-plane. The blocks of order m of the matrix W(λ) with appropriate signs are treated as coefficients of algebraic Riccati equation. It is proved that for any λ with positive
real part this equation has a unique contractive solution θ(λ). The matrix valued function θ(λ) can be represented in a form θ(λ) = θ
A
(iλ) where θ
A
(μ) is the characteristic function of some maximal dissipative operator A. This operator is in a natural way constructed starting from the Hamiltonian system of the form
with periodic coefficients. 相似文献
14.
Francesco Leonetti 《Annali dell'Universita di Ferrara》1985,31(1):169-184
Riassunto In questo lavoro si prova la regolarità h?lderiana delle derivate, fino all'ordinek, dei minimi locali
dei funzionali
sotto opportune ipotesi suA
ij
αβ
e sug.
Summary In this paper we prove h?lder-continuity of the derivates, up to orderk, of local minima of functionals under suitable hypotheses forA ij αβ andg.相似文献
15.
Let A be a Banach algebra which does not contain any nonzero idempotent element, let γ > 0, and let
. We show that if
then
. We also show, assuming a suitable spectral condition on x, that if
, then
Received: 12 July 2006 Revised: 31 January 2007 相似文献
16.
An estimate of
, Ω′⊃⊃Ω, for solutions uε of the family of equations
with a nondifferentiable lower term a is given. The majorant in the estimate depends on
and the distance between Ω′ and ∂Ω, and does not depend on ε. This publication is related to [2, 3]. Bibliography: 4 titles.
Dedicated to V. A. Solonnikov on his sixtieth anniversary
Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 213, 1994, pp. 75–92.
Translated by O. A. Ladyzhenskaya and N. N. Uraltseva. 相似文献
17.
Let n and r be positive integers. Suppose that a family
satisfies F1∩···∩Fr ≠∅ for all F1, . . .,Fr ∈
and
. We prove that there exists ε=ε(r) >0 such that
holds for 1/2≤w≤1/2+ε if r≥13. 相似文献
18.
T. A. Suslina 《Functional Analysis and Its Applications》2012,46(3):234-238
In a bounded domain O ⊂ ℝd with C 1,1 boundary a matrix elliptic second-order operator A D,ɛ with Dirichlet boundary condition is studied. The coefficients of this operator are periodic and depend on x/ɛ, where ɛ s 0 is a small parameter. The sharp-order error estimate $
\left\| {A_{D,\varepsilon }^{ - 1} - \left( {A_D^0 } \right)^{ - 1} } \right\|\left. {L_2 \to L_2 \leqslant C\varepsilon } \right|
$
\left\| {A_{D,\varepsilon }^{ - 1} - \left( {A_D^0 } \right)^{ - 1} } \right\|\left. {L_2 \to L_2 \leqslant C\varepsilon } \right|
相似文献
19.
Marina GHISI Massimo GOBBINO 《数学学报(英文版)》2006,22(4):1161-1170
We consider the Cauchy problem εu^″ε + δu′ε + Auε = 0, uε(0) = uo, u′ε(0) = ul, where ε 〉 0, δ 〉 0, H is a Hilbert space, and A is a self-adjoint linear non-negative operator on H with dense domain D(A). We study the convergence of (uε) to the solution of the limit problem ,δu' + Au = 0, u(0) = u0.
For initial data (u0, u1) ∈ D(A1/2)× H, we prove global-in-time convergence with respect to strong topologies.
Moreover, we estimate the convergence rate in the case where (u0, u1)∈ D(A3/2) ∈ D(A1/2), and we show that this regularity requirement is sharp for our estimates. We give also an upper bound for |u′ε(t)| which does not depend on ε. 相似文献
20.
In this paper, we investigate the complex oscillation of the differential equation
whereA
k−1, …,A
0, F # 0 are finite order transcendental entire functions, such that there exists anA
d(0≤d≤k−1) being dominant in the sense that either it has larger order than any otherA
j(j=0.…,d−1, d+1.…, k−1), or it is the only transcendental function We obtain some precise estimates of the exponent of convergence
of the zero-sequence of solutions to the above equation.
Project supported by the National Natural Science Foundation of China 相似文献