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71.
A finite Borel measure µ on Rd is called R-O varying withindex F if there exist a GL(Rd)-valued function f varying regularlywith index (–F), an increasing function k: (0, ) (0,) with k(t) and k(t + 1)/k(t) c 1 as t , and a -finitemeasure on Rd\0 such that R-O varying measures generalize regularly varying measures introducedby Meerschaert (see M. M. Meerschaert, ‘Regular variationin Rk’, Proc. Amer. Math. Soc. 102 (1988) 341–348)and have numerous applications in limit theorems for probabilitymeasures. For an R-O varying measure µ and – < let denote the tail- andtruncated moment functions of µ in the direction || =1. The purpose of this paper is to show that R-O variation ofa measure implies sharp bounds on the growth rate of the tail-and truncated moment functions depending on the real parts ofthe eigenvalues of the index F along a compact set of directions.Furthermore, bounds on the ratio of these functions for certainvalues of a and b are obtained. 1991 Mathematics Subject Classification:60B10, 28C15.  相似文献   
72.
张新建  童丽 《数学季刊》2001,16(4):18-24
对多变量线性系统,本文给出了求其逆向系统的一种新方法,这种方法将逆向系统计算中高阶矩阵的求逆转化为通过初等变换求低阶矩阵的规范型,比以往的方法更加简单有效且易于编程计算。本文结合系统的可观测空间与不可观测空间的情况,给出了一种特定的等价变换,得到了比通常更低阶的逆向系统。  相似文献   
73.
We study in an algebraic manner the symmetric basis of the Calogero model and the non-symmetric basis of the corresponding Calogero model with distinguishable particles. The Rodrigues formulas are presented for the polynomial parts of both bases. The square norm of the non-symmetric basis is evaluated. Symmetrization of the non-symmetric basis reproduces the symmetric basis and enables us to calculate its square norm.  相似文献   
74.
多变量的SALZER定理   总被引:1,自引:0,他引:1  
本文将在切触有理插值中起重要作用的Salzer定理推广到了多元的情形。  相似文献   
75.
蒋和洋  唐立民 《力学进展》1991,21(4):482-490
本文介绍了非线性多类变量有限元,即非线性的杂交元和拟协调元近几年来的发展及其变分基础.   相似文献   
76.
Fluorescence-activating proteins (FAPs) that bind a chromophore and activate its fluorescence have gained popularity in bioimaging. The fluorescence-activating and absorption-shifting tag (FAST) is a light-weight FAP that enables fast reversible fluorogen binding, thus advancing multiplex and super-resolution imaging. However, the rational design of FAST-specific fluorogens with large fluorescence enhancement (FE) remains challenging. Herein, a new fluorogen directly engineered from green fluorescent protein (GFP) chromophore by a unique double-donor-one-acceptor strategy, which exhibits an over 550-fold FE upon FAST binding and a high extinction coefficient of approximately 100,000 M−1 cm−1, is reported. Correlation analysis of the excited state nonradiative decay rates and environmental factors reveal that the large FE is caused by nonpolar protein−fluorogen interactions. Our deep insights into structure-function relationships could guide the rational design of bright fluorogens for live-cell imaging with extended spectral properties such as redder emissions.  相似文献   
77.
本文在总结多元函数最值求法的基础上,结合实例,指出求解问题中的几个容易被卡住的地方,并给出解决这些问题的几点心得.  相似文献   
78.
A method for solving the linear-quadratic problem of Markov jump linear systems is developed in this paper, relying on the assumption of weak detectability. The concept of weak detectability generalizes previous concepts relevant to this class of systems, and most importantly, it allows us to revisit the quadratic control problem. In the main result of the paper, we show that, for weakly detectable systems, the solution obtained with the new method converges to the solution of the coupled algebraic Riccati equation that arises in the control problem if and only if the system is mean-square stabilizable. The paper shows how the concepts and the method involved are applied by means of numerical examples and comparisons.  相似文献   
79.
基于瞬时混合变分原理与乘积型二元三次 B样条函数 ,以板壳为例 ,建立样条动力方程。引入样条参数及其对时间的导数作为状态变量 ,导出状态方程。对空间域采用混合样条元法 ,对时间域采用现代控制论中的状态空间法。文末数值算例表明 ,计算精度与效率是令人满意的。本文方法对计算多输入与多输出 ,时不变与时变系统和线性与非线性系统等多变量动力响应问题 ,有广阔的应用与发展前景  相似文献   
80.
This paper presents a new methodology to design MIMO digitalPID controllers for multivariable analogue systems with computationalinput time-delay. The preliminarily designed analogue PID controlleris refined using a newly developed state-feedback and state-feedforwardLQR approach. The optimally designed closed-loop system withthe refined MIMO analogue PID controller has pre-assigned closed-loopeigenvalues. A prediction-based digital redesign technique isdeveloped to discretize the cascaded MIMO analogue PID controller,such that the states of the digitally redesigned closed-loopsampled-data system with the MIMO digital PID controller areclose to those of the analogously designed closed-loop systemwith the refined MIMO analogue PID controller. The aforementioneddigital redesign technique is further modified based on thepredictive control method to cope with MIMO analogue systemswith input delay.  相似文献   
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