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排序方式: 共有6083条查询结果,搜索用时 31 毫秒
111.
《Journal of Pure and Applied Algebra》2022,226(12):107144
We consider parametric optimization problems from an algebraic viewpoint. The idea is to find all of the critical points of an objective function thereby determining a global optimum. For generic parameters (data) in the objective function the number of critical points remains constant. This number is known as the algebraic degree of an optimization problem. In this article, we go further by considering the inverse problem of finding parameters of the objective function so it gives rise to critical points exhibiting a special structure. For example if the critical point is in the singular locus, has some symmetry, or satisfies some other algebraic property. Our main result is a theorem describing such parameters. 相似文献
112.
In this paper, the authors study the integral operator
Sφf(z) = Z
C
φ(z, w)f(w)dλα(w)
induced by a kernel function φ(z, ·) ∈ F
∞α between Fock spaces. For 1 ≤ p ≤ ∞, they
prove that Sφ : F
1
α → F
p
α is bounded if and only if
sup
a∈C
kSφkakp,α < ∞, (?)
where ka is the normalized reproducing kernel of F
2
α; and, Sφ : F
1
α → F
p
α is compact if and
only if
lim
|a|→∞
kSφkakp,α = 0.
When 1 < q ≤ ∞, it is also proved that the condition (?) is not sufficient for boundedness
of Sφ : F
q
α → F
p
α .
In the particular case φ(z, w) = eαzw?(z ? w) with ? ∈ F
2
α, for 1 ≤ q < p < ∞, they
show that Sφ : F
p
α → F
q
α is bounded if and only if ? = 0; for 1 < p ≤ q < ∞, they give
sufficient conditions for the boundedness or compactness of the operator Sφ : F
p
α → F
q
α. 相似文献
113.
New Results on Generalized $c$-Distance Without Continuity in Cone $b$-Metric Spaces over Banach Algebras 下载免费PDF全文
Yan Han & Shaoyuan Xu 《分析论及其应用》2022,38(3):335-350
In this work, some new fixed point results for generalized Lipschitz mappings on generalized $c$-distance in cone $b$-metric spaces over Banach algebras are obtained, not acquiring the condition that the underlying cone should be normal or the
mappings should be continuous. Furthermore, the existence and the uniqueness of the
fixed point are proven for such mappings. These results greatly improve and generalize several well-known comparable results in the literature. Moreover, some examples
and an application are given to support our new results. 相似文献
114.
Some Estimates for $θ$-Type Calderόn–Zygmund Operators and Linear Commutators on Certain Weighted Amalgam Spaces 下载免费PDF全文
In this paper, we first introduce some new kinds of weighted amalgam
spaces. Then we discuss the strong type and weak type estimates for a class of
Calderόn–Zygmund type operators $T_θ$ in these new weighted spaces. Furthermore,
the strong type estimate and endpoint estimate of linear commutators $[b, T_θ]$ formed
by $b$ and $T_θ$ are established. Also we study related problems about two-weight, weak
type inequalities for $T_θ$ and $[b, T_θ]$ in the weighted amalgam spaces and give some
results. 相似文献
115.
Gregory L. Eyink 《Journal of statistical physics》1995,78(1-2):353-375
Parisi and Frisch proposed some time ago an explanation for multiscaling of turbulent velocity structure functions in terms of a multifractal hypothesis, i.e., they conjecture that the velocity field has local Hölder exponents in a range [h
min,h
max], with exponents <h occurring on a setS(h) with a fractal dimensionD(h). Heuristic reasoning led them to an expression for the scaling exponentz
p
ofpth order as the Legendre transform of the codimensiond-D(h). We show here that a part of the multifractal hypothesis is correct under even weaker assumptions: namely, if the velocity field hasL
p
-mean Hölder indexs, i.e., if it lies in the Besov spaceB
p
s,
, then local Hölder regularity is satisfied. Ifs<d/p, then the hypothesis is true in a generalized sense of Hölder space with negative exponents and we discuss the proper definition of local Hölder classes of negative index. Finally, if a certain box-counting dimension exists, then the Legendre transform of its codimension gives the scaling exponentz
p
, and, more generally, the maximal Besov index of order,p, ass
p
=z
p
/p. Our method of proof is derived from a recent paper of S. Jaffard using compactly-supported, orthonormal wavelet bases and gives an extension of his results. We discuss implications of the theorems for ensemble-average scaling and fluid turbulence. 相似文献
116.
Vladimir Dobrić 《Journal of Theoretical Probability》1994,7(1):129-134
IfB is a weakly compactly generated Banach space andf: (S,S, ) satisfies the strong law of large numbers, thenf=f
1+f
2, wheref
1 is Bochner -integrable andf
2 is Pettis -integrable with Pettis norm 0. The decomposition is unique. 相似文献
117.
We prove the Cramér theorem forK-invariant Gaussian measures on irreducible symmetric spacesX=G/K withG semisimple noncompact. To do this we use a kind of Abel transform ofK-invariant measures onX.This research is supported by KBN Grant. 相似文献
118.
Alexander Koldobsky 《Journal of Theoretical Probability》1994,7(1):135-145
Let μ be a measure in a Banach spaceE, f be an even function onR. We consider the potentialg(a)=f E f(‖x?a‖)dμ(x). The question is as follows: For whichf does the potentialg determine μ uniquely? In this article we give answers in the cases whereE=l ∞ n and wheref(t)=|t| p andE is a finite dimensional Banach space with symmetric analytic norm. Calculating the Fourier transform of the functionf(‖x‖ ∞) we give a new proof of the J. Misiewicz's result that the functionf(‖x‖ ∞) is positive definite only iff is a constant function. 相似文献
119.
Let and be real Banach spaces. A map between and is called an -bi-Lipschitz map if for all . In this note we show that if is an -bi-Lipschitz map with from onto , then is almost linear. We also show that if is a surjective -bi-Lipschitz map with , then there exists a linear isomorphism such that
where as and .
120.
Friedbert Prü fer Franco Tricerri Lieven Vanhecke 《Transactions of the American Mathematical Society》1996,348(11):4643-4652
We first prove that a Riemannian manifold with globally constant additive Weyl invariants is locally homogeneous. Then we use this result to show that a manifold whose Laplacian commutes with all invariant differential operators is a locally homogeneous space.