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991.
Pekka Korhonen Margareta Soismaa 《The Journal of the Operational Research Society》1981,32(7):577-585
In this paper we are concerned with ranking various orderings of a set of alternatives to a composite order as a multiple criteria problem. The orderings (called preference orderings) can be real preference orderings or any natural orderings. The objective is to find the most preferred order of the decision maker using the preference orderings as criteria.In principle, the problem can be formulated as a multiple objective linear programming problem using the model of Bowman and Colantoni and then solved with the interactive method proposed by Zionts and Wallenius. However, the fact that we are dealing with integer variables prohibits us from applying this approach as such. We discuss the problem formulation and propose a modified approach to that of Zionts and Wallenius for solving the problem. 相似文献
992.
We obtain characterizations of positive Borel measures μ on B
n
so that some weighted holomorphic Besov spaces B
s
p
(ω,B
n
) are embedded in L
p
(d
μ). 相似文献
993.
David Kalaj 《Israel Journal of Mathematics》2011,182(1):123-147
Let ρ
Σ = h(|z|2) be a metric in a Riemann surface Σ, where h is a positive real function. Let H
r
1 = {w = f(z)} be the family of a univalent ρ
Σ harmonic mapping of the Euclidean annulus A(r
1, 1):= {z: r
1 < |z| < 1} onto a proper annulus A
Σ of the Riemann surface Σ, which is subject to some geometric restrictions. It is shown that if A
Σ is fixed, then sup{r
1: ℋ
r
1 ≠ ∅} < 1. This generalizes similar results from the Euclidean case. The cases of Riemann and of hyperbolic harmonic mappings
are treated in detail. Using the fact that the Gauss map of a surface with constant mean curvature (CMC) is a Riemann harmonic
mapping, an application to the CMC surfaces is given (see Corollary 3.2). In addition, some new examples of hyperbolic and
Riemann radial harmonic diffeomorphisms are given, which have inspired some new J. C. C. Nitsche-type conjectures for the
class of these mappings. 相似文献
994.
In this paper we consider the solution of certain convex integer minimization problems via greedy augmentation procedures.
We show that a greedy augmentation procedure that employs only directions from certain Graver bases needs only polynomially
many augmentation steps to solve the given problem. We extend these results to convex N-fold integer minimization problems and to convex 2-stage stochastic integer minimization problems. Finally, we present some
applications of convex N-fold integer minimization problems for which our approach provides polynomial time solution algorithms. 相似文献
995.
This paper consists of two main results. In the first one we describe all Kähler immersions of a bounded symmetric domain into the infinite dimensional complex projective space in terms of the Wallach set of the domain. In the second one we exhibit an example of complete and non-homogeneous Kähler–Einstein metric with negative scalar curvature which admits a Kähler immersion into the infinite dimensional complex projective space. 相似文献
996.
In this paper, stability of a parametric quasivariational inequality of the Minty type is studied via various sufficient conditions characterizing upper and lower semicontinuity of the solution sets as well as the approximate solution sets. Sufficient conditions ensuring upper semicontinuity of the approximate solution sets of an optimization problem with quasivariational inequality constraints are also presented. 相似文献
997.
This paper is concerned with the efficient solution of the linear systems of equations that arise from an adaptive space-implicit
time discretisation of the Black-Scholes equation. These nonsymmetric systems are very large and sparse, so an iterative method
will usually be the method of choice. However, such a method may require a large number of iterations to converge, particularly
when the timestep used is large (which is often the case towards the end of a simulation which uses adaptive timestepping).
An appropriate preconditioner is therefore desirable. In this paper we show that a very simple multigrid algorithm with standard
components works well as a preconditioner for these problems. We analyse the eigenvalue spectrum of the multigrid iteration
matrix for uniform grid problems and illustrate the method’s efficiency in practice by considering the results of numerical
experiments on both uniform grids and those which use adaptivity in space. 相似文献
998.
Vakhid Masagutov 《Arkiv f?r Matematik》2011,49(1):129-148
We prove that every homomorphism \(\mathcal{O}^{E}_{\zeta}\rightarrow\mathcal{O}^{F}_{\zeta}\), with E and F Banach spaces and ζ∈? m , is induced by a \(\mathop{\mathrm{Hom}}(E,F)\)-valued holomorphic germ, provided that 1≤m<∞. A similar structure theorem is obtained for the homomorphisms of type \(\mathcal{O}^{E}_{\zeta}\rightarrow\mathcal{S}_{\zeta}\), where \(\mathcal{S}_{\zeta}\) is a stalk of a coherent sheaf of positive depth. We later extend these results to sheaf homomorphisms, obtaining a condition on coherent sheaves which guarantees the sheaf to be equipped with a unique analytic structure in the sense of Lempert–Patyi. 相似文献
999.
The set of all m × n Boolean matrices is denoted by $
\mathbb{M}
$
\mathbb{M}
m,n
. We call a matrix A ∈ $
\mathbb{M}
$
\mathbb{M}
m,n
regular if there is a matrix G ∈ $
\mathbb{M}
$
\mathbb{M}
n,m
such that AGA = A. In this paper, we study the problem of characterizing linear operators on $
\mathbb{M}
$
\mathbb{M}
m,n
that strongly preserve regular matrices. Consequently, we obtain that if min{m, n} ⩽ 2, then all operators on $
\mathbb{M}
$
\mathbb{M}
m,n
strongly preserve regular matrices, and if min{m, n} ⩾ 3, then an operator T on $
\mathbb{M}
$
\mathbb{M}
m,n
strongly preserves regular matrices if and only if there are invertible matrices U and V such that T(X) = UXV for all X ε $
\mathbb{M}
$
\mathbb{M}
m,n
, or m = n and T(X) = UX
T
V for all X ∈ $
\mathbb{M}
$
\mathbb{M}
n
. 相似文献
1000.
David F. Anderson Scott T. Chapman Nathan Kaplan Desmond Torkornoo 《Semigroup Forum》2011,82(1):96-108
Let M be a commutative, cancellative, atomic monoid and x a nonunit in M. We define ω(x)=n if n is the smallest positive integer with the property that whenever x∣a 1???a t , where each a i is an atom, there is a T?{1,2,…,t} with |T|≤n such that x∣∏k∈T a k . The ω-function measures how far x is from being prime in M. In this paper, we give an algorithm for computing ω(x) in any numerical monoid. Simple formulas for ω(x) are given for numerical monoids of the form 〈n,n+1,…,2n?1〉, where n≥3, and 〈n,n+1,…,2n?2〉, where n≥4. The paper then focuses on the special case of 2-generator numerical monoids. We give a formula for computing ω(x) in this case and also necessary and sufficient conditions for determining when x is an atom. Finally, we analyze the asymptotic behavior of ω(x) by computing \(\lim_{x\rightarrow \infty}\frac{\omega(x)}{x}\). 相似文献