一类零级Dirichlet级数的增长性

本文研究了一类零级Dirichlet级数在全平面上的级、下级以及正规增长性.利用Knopp-Kojima的方法,获得了一类零级Dirichlet级数在全平面上的级、下级以及正规增长性的充要条件,推广了平面上零级Dirichlet级数增长性的研究范围.     

半平面上零级Dirichlet级数的增长性

本文研究半平面上的零级Dirichlet级数的增长性,定义了半平面上的零级Dirichlet级数的指数级和指数下级,通过用零级Dirichlet级数的系数,得到了其与系数之间的关系.     

平面上零级Dirichlet级数和随机Dirichlet级数的上下级

本文对平面上的零级Dirichlet级数和随机Dirichlet级数的上下级进行了研究.利用Newton多边形,在一定条件下得到了Dirichlet级数和随机Dirichlet级数的上下级与其系数的重要关系.推广了平面上的零级Dirichlet级数和随机Dirichlet级数的增长性的研究范围.     

半平面上无限级Dirichlet级数与随机Dirichlet级数的增长性

研究了半平面上无限级Dirichlet级数及随机Dirichlet级数的增长性,利用熊庆来的型函数及Newton多边形,在较宽的系数条件下给出了几个引理,讨论了半平面上无限级Dirichlet级数关于型函数U(r)的级及下级与系数的关系.得到了相应非同分布的无限级随机Dirichlet级数几乎必然(a.s.)有相同的关系.     

全平面上无限级Dirichlet级数的增长性

利用Knopp-Kojima的方法研究在全平面上收敛的无限级Dirichlet级数的增长性,主要是讨论了Dirichlet级数的βU级与下βU级,应用型函数的方法及牛顿多边形,获得了关于βU级增长性的几个定理.     

半平面上Dirichlet级数的广义级与逼近

通过引入广义级概念,讨论了半平面上Dirichlet级数的广义增长性,证明了Dirichlet级数具有两种广义级的等价结果.同时,文章还讨论了具有广义级Dirichlet级数的逼近性质,得到了其逼近算子,广义级,a_n以及λ_n之间的若干关系定理,进一步推广了先前的结果.     

Laplace-Stieltjes变换所确定的整函数的对数级

研究了全平面上收敛的零级Laplce-Stieltjes变换的增长性问题,通过定义对数级和对数下级,得到了零级Laplace-Stieltjes变换具有对数级和对数下级的特征性质,推广了Dirichlet级数相关结果.     

半平面上有限级Dirichlet级数的逼近

主要讨论用Dirichlet多项式去逼近半平面上有限级的Dirichlet级数时产生的误差与原Dirichlet级数的增长级,精确级与型函数之间的联系,得到一些有趣的结果.     

Dirichlet级数和随机Dirichlet级数的下级增长性

本文研究了全平面上零级和有限级Dirichlet级数及随机Dirichlet级数的下级增长性.利用型函数,得到了其系数和增长性之间的关系,以及当随机变量序列{X_n(ω)}满足一定条件时,零级和有限级随机Dirichlet级数在全平面上所确定的随机整函数在每条水平直线上的下级增长性几乎必然与相应的随机Dirichlet级数的下级增长性相同.     

无限级Dirichlet级数的增长性与逼近

文章通过引入β-级的概念讨论了半平面内收敛的无限级Dirichlet级数的增长性.此外,还研究了由Dirichlet多项式逼近β-级Dirichlet级数后的余项,并且得到了余项与增长级的一些关系,以及E_n(f,α)和系数|a_n|之间的等价关系.     

Estimating a survival function with incomplete cause-of-death data

We propose a random censorship model which permits uncertainty in the cause of death assessments for a subset of the subjects in a survival experiment. A nonparametric maximum likelihood approach and a “self-consistency” approach are considered. The solution sets corresponding to both approaches are found. They are infinite and identical. Only some of the solutions are consistent; i.e., the MLEs and self-consistent estimators are not consistent in general. Two estimates are thus proposed and their asymptotic properties are studied. It is shown that both estimates are strongly consistent and converge to Gaussian processes. The covariance structures of these Gaussian processes are derived.     

Depth notions for orthogonal regression

Global depth, tangent depth and simplicial depths for classical and orthogonal regression are compared in examples, and properties that are useful for calculations are derived. The robustness of the maximum simplicial depth estimates is shown in examples. Algorithms for the calculation of depths for orthogonal regression are proposed, and tests for multiple regression are transferred to orthogonal regression. These tests are distribution free in the case of bivariate observations. For a particular test problem, the powers of tests that are based on simplicial depth and tangent depth are compared by simulations.     

On the Geometry of Liouville Equation: Symmetries, Conservation Laws, and Bäcklund Transformations

Various geometrical structures related to the Liouville equation are considered. Properties of the symmetry algebra are discussed and local conserved currents are constructed. Bäcklund transformations for the Liouville equation are integrated and nontrivial generalizations of the latter are studied as well as the structures on them.     

Some properties of singular integral operators over an open curve Dedicated to the 85th birthday of Prof.Lu Jinake

In this paper, the stability properties, the endpoint behavior and the invertible relations of Cauchy-type singular integral operators over an open curve are discussed. If the endpoints of the curve are not special, this type of operators are proved to be stable. At the endpoints, either the singularity or smoothness of the operators are exactly described. And the function sets or spaces on which the operators are invertible as well as the corresponding inverted operators are given. Meanwhile, some applications for the solution of Cauchy-type singular integral equations are illustrated.     

具有双裂纹的弹性复合材料板承受剪切冲击时的动应力强度因子

本文研究了两个材半限弹性的接合面附近存在与接合面平行的双裂纹，并承受剪切冲击时的瞬态应力，运用付里叶（Ｆｏｕｒｉｅｒ）和拉普拉斯（Ｌａｐｌａｃｅ）变换，将问题归结为求解二元积分方程，求解时将裂纹所在面上，下的位移差展成级数，并让其自动满足裂纹面外的位移差为零的条件，利用裂纹面上的边界条件和施密特（Ｓｃｈｍｉｄｔ）方法求解级数中的待定系数，在拉普拉斯像空间中，求得动应力强度因子，并将其数值地逆变换至     

Morse decompositions of nonautonomous dynamical systems

The global asymptotic behavior of dynamical systems on compact metric spaces can be described via Morse decompositions. Their components, the so-called Morse sets, are obtained as intersections of attractors and repellers of the system. In this paper, new notions of attractor and repeller for nonautonomous dynamical systems are introduced which are designed to establish nonautonomous generalizations of the Morse decomposition. The dynamical properties of these decompositions are discussed, and nonautonomous Lyapunov functions which are constant on the Morse sets are constructed explicitly. Moreover, Morse decompositions of one-dimensional and linear systems are studied.

     

On the Least Number of Fixed Points of an Equivariant Map

The problem on the least number of fixed points of an equivariant map of a compact polyhedron on which a finite group acts is considered. For such a map, the least number of fixed points and the least number of fixed orbits are estimated in terms of invariants of the type of Nielsen numbers. The estimates obtained are sharp. The results are similar to those of P. Wong, but their assumptions are essentially weaker. Some notations are refined. The proofs are constructive.     

Pseudospectra and stability radii for analytic matrix functions with application to time-delay systems

Definitions for pseudospectra and stability radii of an analytic matrix function are given, where the structure of the function is exploited. Various perturbation measures are considered and computationally tractable formulae are derived. The results are applied to a class of retarded delay differential equations. Special properties of the pseudospectra of such equations are determined and illustrated.     

Some properties of singular integral operators over an open curve Dedicated to the 85th birthday of Prof. Lu Jianke

In this paper, the stability properties, the endpoint behavior and the invertible relations of Cauchy-type singular integral operators over an open curve are discussed. If the endpoints of the curve are not special, this type of operators are proved to be stable. At the endpoints, either the singularity or smoothness of the operators are exactly described. And the function sets or spaces on which the operators are invertible as well as the corresponding inverted operators are given. Meanwhile, some applications for the solution of Cauchy-type singular integral equations are illustrated.     

Differential sensitivity of solutions of convex constrained optimal control problems for discrete systems

A family of optimal control problems for discrete systems that depend on a real parameter is considered. The problems are strongly convex and subject to state and control constraints. Some regularity conditions are imposed on the constraints.The control problems are reformulated as mathematical programming problems. It is shown that both the primal and dual optimal variables for these problems are right-differentiable functions of a parameter. The right-derivatives are characterized as solutions to auxiliary quadratic control problems. Conditions of continuous differentiability are discussed, and some estimates of the rate of convergence of the difference quotients to the respective derivatives are given.