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1.
In the present paper, we introduce Euler sequence spaces e
0
r
and e
c
r
of nonabsolute type that are BK-spaces including the spaces c
0 and c and prove that the spaces e
0
r
and e
c
r
are linearly isomorphic to the spaces c
0 and c, respectively. Furthermore, some inclusion theorems are presented. Moreover, the α-, β-, γ- and continuous duals of the spaces e
0
r
and e
c
r
are computed and their bases are constructed. Finally, necessary and sufficient conditions on an infinite matrix belonging to the classes
and
are established, and characterizations of some other classes of infinite matrices are also derived by means of a given basic lemma, where 1 ≤ p ≤ ∞.__________Published in Ukrains’kyi Matematychnyi Zhurnal, Vol. 57, No. 1, pp. 3–17, January, 2005. 相似文献
2.
Chao Yang Chunyan Hao Jianzhong Zhang 《Mathematical Methods of Operations Research》2007,66(2):225-233
In this paper we consider problems of the following type: Let E = { e
1, e
2,..., e
n
} be a finite set and be a family of subsets of E. For each element e
i
in E, c
i
is a given capacity and
i
is the cost of increasing capacity c
i
by one unit. It is assumed that we can expand the capacity of each element in E so that the capacity of family can be expanded to a level r. For each r, let f (r) be the efficient function with respect to the capacity r of family , and be the cost function for expanding the capacity of family to r. The goal is to find the optimum capacity value r
* and the corresponding expansion strategy so that the pure efficency function is the largest. Firstly, we show that this problem can be solved efficiently by figuring out a series of bottleneck capacity
expansion problem defined by paper (Yang and Chen, Acta Math Sci 22:207–212, 2002) if f (r) is a piecewise linear function. Then we consider two variations and prove that these problems can be solved in polynomial
time under some conditions. Finally the optimum capacity for maximum flow expansion problem is discussed. We tackle it by
constructing an auxiliary network and transforming the problem into a maximum cost circulation problem on the auxiliary network. 相似文献
3.
A. M. Gomilko 《Ukrainian Mathematical Journal》2004,56(8):1212-1226
We consider the problem of estimates for the powers of the Cayley transform V = (A + I)(A - I)–1 of the generator of a uniformly bounded C
0-semigroup of operators e
tA
, t 0, that acts in a Hilbert space H. In particular, we establish the estimate
. We show that the estimate
is true in the following cases: (a) the semigroups e
tA
and
are uniformly bounded; (b) the semigroup e
tA
uniformly bounded for t is analytic (in particular, if the generator of the semigroup is a bounded operator).Translated from Ukrainskyi Matematychnyi Zhurnal, Vol. 56, No. 8, pp. 1018–1029, August, 2004. 相似文献
4.
We prove the following statement.
Let , and let . Suppose that, for all and , the sequence satisfies the relation
where e(u) : = e2πiu
.
Then
where
q is the set of q-multiplicative functions g such that . 相似文献
5.
6.
On existence, uniform decay rates and blow up for solutions of the 2-D wave equation with exponential source 总被引:1,自引:0,他引:1
Claudianor O. Alves Marcelo M. Cavalcanti 《Calculus of Variations and Partial Differential Equations》2009,34(3):377-411
This paper is concerned with the study of the nonlinear damped wave equation
where Ω is a bounded domain of having a smooth boundary ∂Ω = Γ. Assuming that g is a function which admits an exponential growth at the infinity and, in addition, that h is a monotonic continuous increasing function with polynomial growth at the infinity, we prove both: global existence as
well as blow up of solutions in finite time, by taking the initial data inside the potential well. Moreover, optimal and uniform
decay rates of the energy are proved for global solutions.
The author is Supported by CNPq 300959/2005-2, CNPq/Universal 472281/2006-2 and CNPq/Casadinho 620025/2006-9.
Research of Marcelo M. Cavalcanti partially supported by the CNPq Grant 300631/2003-0. 相似文献
7.
Marcelo M. Cavalcanti Valéria N. Domingos Cavalcanti Ryuichi Fukuoka Daniel Toundykov 《Journal of Evolution Equations》2009,9(1):143-169
This paper is devoted to the study of uniform energy decay rates of solutions to the wave equation with Cauchy–Ventcel boundary
conditions:
where Ω is a bounded domain of (n ≥ 2) having a smooth boundary , such that with , being closed and disjoint. It is known that if a(x) = 0 then the uniform exponential stability never holds even if a linear frictional feedback is applied to the entire boundary of the domain [see, for instance, Hemmina (ESAIM, Control Optim Calc Var 5:591–622, 2000, Thm. 3.1)]. Let be a smooth function; define ω
1 to be a neighbourhood of , and subdivide the boundary into two parts: and . Now, let ω
0 be a neighbourhood of . We prove that if a(x) ≥ a
0 > 0 on the open subset and if g is a monotone increasing function satisfying k|s| ≤ |g(s)| ≤ K|s| for all |s| ≥ 1, then the energy of the system decays uniformly at the rate quantified by the solution to a certain nonlinear ODE dependent
on the damping [as in Lasiecka and Tataru (Differ Integral Equ 6:507–533, 1993)].
Research of Marcelo M. Cavalcanti was partially supported by the CNPq Grant 300631/2003-0.
Research of Valéria N. Domingos Cavalcanti was partially supported by the CNPq Grant 304895/2003-2. 相似文献
8.
9.
Letc
n
(A) denote the codimensions of a P.I. algebraA, and assumec
n
(A) has a polynomial growth:
. Then, necessarily,q∈ℚ [D3]. If 1∈A, we show that
, wheree=2.71…. In the non-unitary case, for any 0<q∈ℚ, we constructA, with a suitablek, such that
.
In memory of S. A. Amitsur, our teacher and friend
Partially supported by Grant MM404/94 of Ministry of Education and Science, Bulgaria and by a Bulgarian-American Grant of
NSF.
Partially supported by NSF grant DMS-9101488. 相似文献
10.
Sun Zhonghua Qi Wenfeng 《高校应用数学学报(英文版)》2007,22(4):469-477
Let Z/(pe) be the integer residue ring modulo pe with p an odd prime and integer e ≥ 3. For a sequence (a) over Z/(pe), there is a unique p-adic decomposition (a) = (a)0 (a)1·p … (a)e-1 ·pe-1, where each (a)i can be regarded as a sequence over Z/(p), 0 ≤ i ≤ e - 1. Let f(x) be a primitive polynomial over Z/(pe) and G' (f(x), pe) the set of all primitive sequences generated by f(x) over Z/(pe). For μ(x) ∈ Z/(p)[x] with deg(μ(x)) ≥ 2 and gcd(1 deg(μ(x)),p- 1) = 1,set ψe-1 (x0, x1,…, xe-1) = xe-1·[ μ(xe-2) ηe-3 (x0, x1,…, xe-3)] ηe-2 (x0, x1,…, xe-2),which is a function of e variables over Z/(p). Then the compressing map ψe-1: G'(f(x),pe) → (Z/(p))∞,(a) (→)ψe-1((a)0, (a)1,… ,(a)e-1) is injective. That is, for (a), (b) ∈ G' (f(x), pe), (a) = (b) if and only if ψe - 1 ((a)0, (a)1,… , (a)e - 1) =ψe - 1 ((b)0,(b)1,… ,(b)e-1). As for the case of e = 2, similar result is also given. Furthermore, if functions ψe-1 and ψe-1 over Z/(p) are both of the above form and satisfy ψe-1((a)0,(a)1,… ,(a)e-1) = ψe-1((b)0,(b)1,… ,(b)e-1) for (a),(b) ∈ G'(f(x),pe), the relations between (a) and (b), ψe-1 and ψe-1 are discussed. 相似文献
11.
V. V. Makeev 《Journal of Mathematical Sciences》2007,140(4):558-563
Let ℝn be the n-dimensional Euclidean space, and let { · } be a norm in Rn. Two lines ℓ1 and ℓ2 in ℝn are said to be { · }-orthogonal if their { · }-unit direction vectors e
1 and e
2 satisfy {e
1 + e
2} = {e
1 − e
2}. It is proved that for any two norms { · } and { · }′ in ℝn there are n lines ℓ1, ..., ℓn that are { · }-and { · }′-orthogonal simultaneously. Let
be a continuous function on the unit sphere
with center O. It is proved that there exists an (n − 1)-cube C centered at O, inscribed in
, and such that all sums of values of f at the vertices of (n − 3)-faces of C are pairwise equal. If the function f is even,
then there exists an n-cube with the same properties. Furthermore, there exists an orthonormal basis e
1, ..., e
n such that for 1 ≤ i ≤ j ≤ n we have
. Bibliography: 8 titles.
__________
Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 329, 2005, pp. 107–117. 相似文献
12.
In this paper we study tight lower bounds on the size of a maximum matching in a regular graph. For k ≥3, let G be a connected k-regular graph of order n and let α′(G) be the size of a maximum matching in G. We show that if k is even, then
, while if k is odd, then
. We show that both bounds are tight.
Research supported in part by the South African National Research Foundation and the University of KwaZulu-Natal. 相似文献
13.
Let X be a Banach space and let
A be a closed linear operator on
X. It is shown that the abstract Cauchy problem
enjoys maximal regularity in weighted
L
p
-spaces with weights
, where
,
if and only if it has the property of maximal
L
p
-regularity.
Moreover, it is also shown that the derivation operator
admits an
-calculus in weighted
L
p
-spaces.
Received: 26 February 2003 相似文献
14.
We prove the estimate
for the number Ek(N)
of k-tuples
(n + a1,..., n + ak) of primes not exceeding N,
for k of size c1 log N and
N sufficiently large.
A bound of this strength was previously known in the special case
<
only, (Vaughan, 1973). For general ai this is an improvement upon the work of
Hofmann and Wolke (1996).
The number of prime tuples of this size has
considerable oscillations, when varying the prime pattern.
Received: 20 December 2002 相似文献
15.
Marek Omelka 《Annals of the Institute of Statistical Mathematics》2007,59(2):385-402
The rank statistic
, with R
i
(t) being the rank of
and e
1
, . . . , e
n
being the random sample from a distribution with a cdf F, is considered as a random process with t in the role of parameter. Under some assumptions on c
i
, x
i
and on the underlying distribution, it is proved that the process
converges weakly to the Gaussian process. This generalizes the existing results where the one-dimensional case
was considered. We believe our method of the proof can be easily modified for the signed-rank statistics of Wilcoxon type.
Finally, we use our results to find the second order asymptotic distribution of the R-estimator based on the Wilcoxon scores and also to investigate the length of the confidence interval for a single parameter
β
l
. 相似文献
16.
Shahar Mendelson 《Mathematische Annalen》2008,340(2):293-314
Let F be a class of functions on a probability space (Ω, μ) and let X
1,...,X
k
be independent random variables distributed according to μ. We establish an upper bound that holds with high probability
on for every t > 0, and that depends on a natural geometric parameter associated with F. We use this result to analyze the supremum of empirical processes of the form for p > 1 using the geometry of F. We also present some geometric applications of this approach, based on properties of the random operator 〈X
i
, ·〉e
i
, where are sampled according to an isotropic, log-concave measure on . 相似文献
17.
Vladislav Kargin 《Probability Theory and Related Fields》2007,139(3-4):397-413
Let X
i
denote free identically-distributed random variables. This paper investigates how the norm of products behaves as n approaches infinity. In addition, for positive X
i
it studies the asymptotic behavior of the norm of where denotes the symmetric product of two positive operators: . It is proved that if EX
i
= 1, then is between and c
2
n for certain constant c
1 and c
2. For it is proved that the limit of exists and equals Finally, if π is a cyclic representation of the algebra generated by X
i
, and if ξ is a cyclic vector, then for all n. These results are significantly different from analogous results for commuting random variables. 相似文献
18.
Christer Borell 《Probability Theory and Related Fields》2008,140(1-2):195-205
Let be an integer, let γ be the standard Gaussian measure on , and let . Given this paper gives a necessary and sufficient condition such that the inequality is true for all Borel sets A
1,...,A
m
in of strictly positive γ-measure or all convex Borel sets A
1,...,A
m
in of strictly positive γ-measure, respectively. In particular, the paper exhibits inequalities of the Brunn–Minkowski type
for γ which are true for all convex sets but not for all measurable sets.
相似文献
19.
LetF be a commutative ring with 1, letA, be a primeF-algebra with Martindale extended centroidC and with central closureA
c
and letR be a noncentral Lie ideal of the algebraA generatingA. Further, letZ(R) be the center ofR, let
be the factor Lie algebra and let δ:
be a Lie derivation. Suppose that char(A) ≠ 2 andA does not satisfySt
14, the standard identity of degree 14. We show thatR ΩC =Z(R) and there exists a derivation of algebrasD:A →A
c
such that
for allx∈R. Our result solves an old problem of Herstein. 相似文献
20.
Let {εt;t ∈ Z} be a sequence of m-dependent B-valued random elements with mean zeros and finite second moment. {a3;j ∈ Z} is a sequence of real numbers satisfying ∑j=-∞^∞|aj| 〈 ∞. Define a moving average process Xt = ∑j=-∞^∞aj+tEj,t ≥ 1, and Sn = ∑t=1^n Xt,n ≥ 1. In this article, by using the weak convergence theorem of { Sn/√ n _〉 1}, we study the precise asymptotics of the complete convergence for the sequence {Xt; t ∈ N}. 相似文献