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11.
Nobuhiro Honda 《Mathematische Nachrichten》2003,256(1):48-57
In a previous paper of the same title the author gave a generalization of the constrution of Donaldson–Friedman, to prove the existence of twistor spaces of n CP 2 with a special kind of divisors. In the present paper, we consider its equivariant version. When n = 3, this gives another proof of the existence of degenerate double solid with C *–action, and we show that the branch quartic surface is birational to an elliptic ruled surface. In case n ≥ 4, this yields new Moishezon twistor spaces with C *–action, which is shown to be the most degenerate ones among twistor spaces studied by Campana and Kreußler. 相似文献
12.
Given a tree
with leaf set X, there are certain ways of arranging the elements of X in a circular order so that
can be embedded in the plane and ‘preserve’ this ordering. We investigate some new combinatorial properties of these ‘circular orderings.’ We then use these properties to establish two results concerning dissimilarity maps on X that are induced by edge-weighted trees with leaf set X. 相似文献
13.
Keye Martin 《Applied Categorical Structures》2003,11(1):27-40
We introduce the triangle inequality for measurement. This is a property that when satisfied by a measurement enables one to construct a metric on the set of elements with measure zero that yields the relative Scott topology. The naturality of this construction permits a categorical solution to the model problem in domain theory for locally compact metric spaces. The first time such a solution has been achieved. 相似文献
14.
A. J. Zaslavski 《Journal of Optimization Theory and Applications》2004,123(3):695-712
In our previous work, a generic well-posedness result (with respect to variations of the integrand of the integral functional) without the convexity condition was established for a class of optimal control problems satisfying the Cesari growth condition. In this paper, we extend this generic well-posedness result to classes of constrained variational problems in which the values at the endpoints and constraint maps are also subject to variations. 相似文献
15.
The main purpose of this paper is to use a mean value theorem of Dirichlet L-functions to study the asymptotic property of a hybrid mean value of a generalized Cochrane sum, and give an interesting mean value formula.2000 Mathematics Subject Classification: Primary—11F20; Secondary—11F99 相似文献
16.
Rie Natsui 《Acta Mathematica Hungarica》2005,108(4):299-318
Summary Let Fq be a finite field with q elements. We consider formal Laurent series of Fq -coefficients with their continued fraction expansions by Fq -polynomials. We prove some arithmetic properties for almost every formal Laurent series with respect to the Haar measure. We construct a group extension of the non-archimedean continued fraction transformation and show its ergodicity. Then we get some results as an application of the individual ergodic theorem. We also discuss the convergence rate for limit behaviors. 相似文献
17.
该文利用算子半群的方法给出了取值于具有左不变度量的完备可分群的齐次Levy过程是复合Poisson过程的弱极限这一结论. 相似文献
18.
Ignacio Bajo 《Geometriae Dedicata》1997,66(3):281-291
Lie groups with bi-invariant semi-Riemannian metrics are considered. We study the decomposition of the algebra of prederivations of a direct sum of Lie algebras and derive some results on the isotropy group of a bi-invariant product Lie group. We also give necessary and sufficient conditions to ensure that all isometries of a complex Lie group, endowed with a bi-invariant Norden metric, are holomorphic. 相似文献
19.
E. D. Nursultanov 《Mathematical Notes》1998,63(2):205-214
In this paper we prove theorems on multiplicators of Fourier series inL
p, where the conditions depend on a parameterp. An example illustrating the importance of these conditions is constructed.
Translated fromMatematicheskie Zametki, Vol. 63, No. 2, pp. 235–247, February, 1998. 相似文献
20.
本文引进了广义极限鞅的概念,证明了 L~1有界的广义极限鞅 a.s.收敛于—可积随机变量。这样推广了通常极限鞅的相应收敛定理,并回答了 Stout 提出的问题:L~1有界的弱鞅在一定的条件下是 a.s.收敛的。 相似文献