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1.
本文处理能在Banach空间中实现的线性连续时间系统.这里,输入、输出和状态空间都是无穷维Banach空间.我们证明:加权模式有Banach空间实现的充要条件是它强连续且为指数阶.对状态算子是解析半群的无穷小生成元的情况,得到了Banach空间实现的存在性定理.所有定理都是在时间域中给出的.  相似文献   

2.
一类弱稳定的Banach空间   总被引:1,自引:1,他引:0  
为了解决什么样的Banach空间,它的每个无穷维子空间几乎等距地含有C0或lp(1≤p<∞)问题,J.L.Krivine1979年在[4]中引进了稳定的Banach空间的概念.S.Argyors.在[2]中引进了弱稳定的概念,列举了一个弱稳定而非稳定的Banach空间,本文引进具有P-凸完备极小系的Banach空间,证明了该空间是弱稳定以及可赋等价的稳定范数的充要条件是其自反.最后给出了不自反的具有P—凸完备极小系的Banach空间的例子从而推广了[2]中结果.  相似文献   

3.
本文利用(广义)拓扑度的有关性质给出了一般复Banach空间上全纯映射的(广义)Rouché定理.特别,在复平面上它以经典的Rouché定理为特例.同时,它也给出了多复变全纯映射的相应定理及一些应用.  相似文献   

4.
本文定义了Banach空间值的随机测度的弱*收敛的概念,并表征了Banach空间值的对称独立散射随机测度的弱*收敛性.另一方面,证明了,关于Banach空间值的对称独立散射随机测度在较弱意义下的结果,即弱收敛推得弱*收敛.  相似文献   

5.
本文用Nevanlinna值分布论对一般n阶常微分方程进行了研究,从而推广了Relich—Witich定理.  相似文献   

6.
本文研究了Banach空间的弱序列紧性.Banach空间X称为有(w)性质,如果X(X的共轭空间)的每个有界序列有弱收敛子列.我们证明了,如果Banach空间X有(w)性质,那么lp(X)(1≤p<+∞)与c0(X)也有(w)性质.  相似文献   

7.
P.N.Dowling和C.J.Lennard证明了含渐近等距于l_1子空间的Banach空间不具有不动点性质.本文以对偶形式给出了Banach空间合渐近等距于l_1或c_0子空间的充分必要条件,并证明了当一个Banach空间含有渐近等距于l_∞子空间时它必含有渐近等于l_1子空间.  相似文献   

8.
Lorentz序列空间的装球问题   总被引:1,自引:0,他引:1  
叶以宁  张波 《数学学报》1994,37(5):611-620
Banach空间中装球问题的研究,近四十年来已取得了令人瞩目的发展。Banach空间的装球值的范围已经确定,L_p空间及Orlicz序列空间I_M等许多经典Banach空间装球值已经找到.本文研究又一类经典Banach空间──Lorentz序列空间的装球问题,给出了Lorentz序列空间的装球值。  相似文献   

9.
Banach空间中渐近正则的Lipschitz半群的不动点定理   总被引:1,自引:0,他引:1  
本文首先定义了渐近正则的Lipschitz半群的概念.其次,证明了p一致凸Banach空间中渐近正则的Lipschitz半群的不动点定理.同时也证明了具有正规结构系数的一致凸Eanach空间中的渐近正则的Lipschitz半群的一个新的不动点定理.  相似文献   

10.
本文引入了Banacj空间X的弱局部Z性质和弱Z性质,得出了:Banach空间X是K-NUC空间的一个充分必要条件和Banach空间X是LK-NUC空间的一个充分条件,并指出弱Z性质蕴含弱Banach-Saks性质.  相似文献   

11.
碾压混凝土坝施工层面变形分析模型   总被引:1,自引:0,他引:1  
针对碾压混凝土坝施工层面对大坝变形产生显著影响的问题,深入研究了施工层面的变化性质及规律,提出了层面不同阶段变形的模拟方法,建立了施工层面有厚度和无厚度分析模型,提出的模型能反映层面的弹性变形、衰减蠕变、不可逆变形以及加速蠕变等变形状态.实例分析表明:所提出的碾压混凝土坝施工层面有厚度和无厚度分析模型能较客观地模拟大坝的结构变化形态,尤其是施工层面有厚度分析模型较完整地模拟了层面的渐变规律,其计算结果与原位监测成果吻合较好.同时,提出的方法和建立的分析模型可推广应用于常规混凝土坝,特别是坝基内断层和夹层等变形规律的分析.  相似文献   

12.
有资格限制的指派问题的求解方法   总被引:3,自引:0,他引:3  
在实际的指派工作中,常会遇到某个人有没有资格去承担某项工作的问题,因此,本建立了有资格限制的指派问题的数学模型。在此数学模型中,将效益矩阵转化为判定矩阵,由此给出了判定此种指派问题是否有解的方法;在有解的情况下,进一步将效益矩阵转化为求解矩阵,从而将有资格限制的指派问题化为传统的指派问题来求解。最后给出了一个数值例子来说明这样的处理方法是有效的。  相似文献   

13.
An estimator of the number of components of a finite mixture ofk-dimensional distributions is given on the basis of a one-dimensional independent random sample obtained by a transformation of ak-dimensional independent random sample. A consistency of the estimator is shown. Some simulation results are given in a case of finite mixtures of two-dimensional normal distributions.  相似文献   

14.
The Gauss-Lucas Theorem on the roots of polynomials nicely simplifies the computation of the subderivative and regular subdifferential of the abscissa mapping on polynomials (the maximum of the real parts of the roots). This paper extends this approach to more general functions of the roots. By combining the Gauss-Lucas methodology with an analysis of the splitting behavior of the roots, we obtain characterizations of the subderivative and regular subdifferential for these functions as well. In particular, we completely characterize the subderivative and regular subdifferential of the radius mapping (the maximum of the moduli of the roots). The abscissa and radius mappings are important for the study of continuous and discrete time linear dynamical systems. Dedicated to R. Tyrrell Rockafellar on the occasion of his 70th birthday. Terry is one of those rare individuals who combine a broad vision, deep insight, and the outstanding writing and lecturing skills crucial for engaging others in his subject. With these qualities he has won universal respect as a founding father of our discipline. We, and the broader mathematical community, owe Terry a great deal. But most of all we are personally thankful to Terry for his friendship and guidance. Research supported in part by the National Science Foundation Grant DMS-0203175. Research supported in part by the Natural Sciences and Engineering Research Council of Canada. Research supported in part by the National Science Foundation Grant DMS-0412049.  相似文献   

15.
本文分析了15具白骨化尸体标本的股骨汞(Hg),铅(Pb),镉(Cd)元素含量数据,在三年的时间内采集了3次,一共收集到45个数据。首先将这组数据看着纵向数据,利用线性随机效应混合模型、Cox随机混合效应模型进行分析,结果显示,如果对每个白骨化尸体标本建立线性模型,可以精确预测出死亡时间,而且不需要采集铅元素含量数据。混合效应模型的预测效果也很好,最大误差不会超过1个月。其次我们对数据不作任何假设,利用机器学习中随机森林方法分析数据,并利用5折交叉验证方法来判断结果的可靠性,训练集和测试集的NMSE分别为0.1205944,0.5604286,因此可以用训练出的模型来预测死亡时间。  相似文献   

16.
The aim of this paper is to establish the uniform convergence of the densities of a sequence of random variables, which are functionals of an underlying Gaussian process, to a normal density. Precise estimates for the uniform distance are derived by using the techniques of Malliavin calculus, combined with Stein?s method for normal approximation. We need to assume some non-degeneracy conditions. First, the study is focused on random variables in a fixed Wiener chaos, and later, the results are extended to the uniform convergence of the derivatives of the densities and to the case of random vectors in some fixed chaos, which are uniformly non-degenerate in the sense of Malliavin calculus. Explicit upper bounds for the uniform norm are obtained for random variables in the second Wiener chaos, and an application to the convergence of densities of the least square estimator for the drift parameter in Ornstein–Uhlenbeck processes is discussed.  相似文献   

17.
Extreme values of the sum of squares of degrees of bipartite graphs   总被引:1,自引:0,他引:1  
In this paper we determine the minimum and maximum values of the sum of squares of degrees of bipartite graphs with a given number of vertices and edges.  相似文献   

18.
19.
Interferons are active biomolecules, which help fight viral infections by spreading from infected to uninfected cells and activate effector molecules, which confer resistance from the virus on cells. We propose a new model of dynamics of viral infection, including endocytosis, cell death, production of interferon and development of resistance. The novel element is a specific biologically justified mechanism of interferon action, which results in dynamics different from other infection models. The model reflects conditions prevailing in liquid cultures (ideal mixing), and the absence of cells or virus influx from outside. The basic model is a nonlinear system of five ordinary differential equations. For this variant, it is possible to characterise global behaviour, using a conservation law. Analytic results are supplemented by computational studies. The second variant of the model includes age-of-infection structure of infected cells, which is described by a transport-type partial differential equation for infected cells. The conclusions are: (i) If virus mortality is included, the virus becomes eventually extinct and subpopulations of uninfected and resistant cells are established. (ii) If virus mortality is not included, the dynamics may lead to extinction of uninfected cells. (iii) Switching off the interferon defense results in a decrease of the sum total of uninfected and resistant cells. (iv) Infection-age structure of infected cells may result in stabilisation or destabilisation of the system, depending on detailed assumptions. Our work seems to constitute the first comprehensive mathematical analysis of the cell-virus-interferon system based on biologically plausible hypotheses.  相似文献   

20.
N/Kbe a Galois extension of number fields with finite Galois group G.We describe a new approach for constructing invariants of the G-module structure of the K groups of the ring of integers of N in the Grothendieck group of finitely generated projective Z[G]modules. In various cases we can relate these classes, and their function field counterparts, to the root number class of Fröhlich and Cassou-Noguès.  相似文献   

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