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91.
Let M be a smooth manifold endowed with a symmetric connection . There are two important ways of lift the connection of M to the frame bundle BM, the canonical lift and the horizontal lift . The aim of this work is determine the -martingales and the -martingales on BM. Our results allow to establish new characterizations of harmonic maps from Riemannian manifolds to frame bundles.
The research of P. Catuogno is supported in part by FAPESP 01/13158-4 and S. Stelmastchuk is fully supported by FAPESP 02/12154-8. 相似文献
92.
Dejan Kolaric 《Proceedings of the American Mathematical Society》2008,136(4):1273-1284
Let be a closed polydisc or ball in , and let be a quasi-projective algebraic manifold which is Zariski locally equivalent to , or a complement of an algebraic subvariety of codimension in such a manifold. If is an integer satisfying , then every holomorphic map from a neighborhood of to with rank at every point of can be approximated uniformly on by entire maps with rank at every point of .
93.
In this paper we show how the metric theory of tensor products developed by Grothendieck perfectly fits in the study of channel capacities, a central topic in Shannon's information theory. Furthermore, in the last years Shannon's theory has been fully generalized to the quantum setting, and revealed qualitatively new phenomena in comparison. In this paper we consider the classical capacity of quantum channels with restricted assisted entanglement. These capacities include the classical capacity and the unlimited entanglement-assisted classical capacity of a quantum channel. Our approach to restricted capacities is based on tools from functional analysis, and in particular the notion of p -summing maps going back to Grothendieck's work. Pisier's noncommutative vector-valued Lp spaces allow us to establish the new connection between functional analysis and information theory in the quantum setting. 相似文献
94.
We present a new mesh simplification technique developed for a statistical analysis of a large data set distributed on a generic complex surface, topologically equivalent to a sphere. In particular, we focus on an application to cortical surface thickness data. The aim of this approach is to produce a simplified mesh which does not distort the original data distribution so that the statistical estimates computed over the new mesh exhibit good inferential properties. To do this, we propose an iterative technique that, for each iteration, contracts the edge of the mesh with the lowest value of a cost function. This cost function takes into account both the geometry of the surface and the distribution of the data on it. After the data are associated with the simplified mesh, they are analyzed via a spatial regression model for non-planar domains. In particular, we resort to a penalized regression method that first conformally maps the simplified cortical surface mesh into a planar region. Then, existing planar spatial smoothing techniques are extended to non-planar domains by suitably including the flattening phase. The effectiveness of the entire process is numerically demonstrated via a simulation study and an application to cortical surface thickness data. 相似文献
95.
设(Xni:1≤i≤n,n≥1)为行间ND阵列,g(x)是R^+上指数为α的正则变化函数,{αni:1≤i≤n,n≥1}为满足条件max1≤i≤n|ani|=0((g(n))^-1)的实数阵列.本文采用截尾的方法,得到了使ND随机变量阵列加权乘积和完全收敛的条件,并推广了以前学者的结论. 相似文献
96.
何卫民 《纯粹数学与应用数学》2010,26(2):211-214
引入了Scott相容连续映射与商相容Domain等概念,研究了Scott相容连续映射保局部基与保waybelow序及保局部基与保紧元之间的关系,证明了相容连续Domain或相容代数Domain在保局部基的Scott相容连续满映射下保持不变. 相似文献
97.
研究了Banach空间中有限个渐近伪压缩映射近迫点序列的收敛性问题,此结果推广了以前的结论. 相似文献
98.
99.
A regular perturbation analytical‐numerical method for the evolution of precancerous lesions caused by the human papillomavirus 下载免费PDF全文
Silvia Jerez Luz Maria Gonzalez Francisco J. Solis 《Numerical Methods for Partial Differential Equations》2015,31(3):847-855
A numerical method is developed to analyze the behavior of the evolution of the lesions at the cervical cells caused by the human papillomavirus. The model to be solved consists in a one‐dimensional nonlinear advection–diffusion‐reaction equation. Such equation is approximated by a consistent explicit difference scheme which is based on regular perturbation theory. A constructive procedure for the numerical scheme is given and finally an illustrative example of the evolution of a mild dysplasia is included. © 2014 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 31: 847–855, 2015 相似文献
100.
Let be two monomial ideals of the polynomial ring . In this paper, we provide two lower bounds for the Stanley depth of . On the one hand, we introduce the notion of lcm number of , denoted by , and prove that the inequality holds. On the other hand, we show that , where denotes the order dimension of the lcm lattice of . We show that I and satisfy Stanley's conjecture, if either the lcm number of I or the order dimension of the lcm lattice of I is small enough. Among other results, we also prove that the Stanley–Reisner ideal of a vertex decomposable simplicial complex satisfies Stanley's conjecture. 相似文献