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991.
The question of what limits the amplitude of the oscillations of clarinet-like instruments is investigated. The study is based on numerical simulations in which two kind of losses are taken into account: linear losses and non-linear losses localised at the open end of the tube. The influence of the amount of losses on the saturation process and on the playing range of clarinet-like instruments is shown. Results are confirmed by experiments using an artificial mouth in which the non-linear losses are varied using several terminations with different geometries. 相似文献
992.
993.
Abdellah Bnouhachem 《Journal of Mathematical Analysis and Applications》2006,314(2):513-525
In this paper, we presented a new projection and contraction method for linear variational inequalities, which can be regarded as an extension of He's method. The proposed method includes several new methods as special cases. We used a self-adaptive technique to adjust parameter β at each iteration. This method is simple, the global convergence is proved under the same assumptions as He's method. Some preliminary computational results are given to illustrate the efficiency of the proposed method. 相似文献
994.
本文讨论了带有结构性不确定的线性时变系统的二次镇定问题.建立了H∞指标γ和RDE及RDI之间的等价关系,并给出了带有结构性不确定线性时变系统二次稳定的充分条件;在此基础上将带有结构性不确定线性时变系统的鲁棒动态补偿器设计转化成求解一个相应的确定性辅助线性时变系统的标准H~∞控制问题. 相似文献
995.
996.
Fatma Taşdelen Ali Olgun Gülen Başcanbaz-Tunca 《Proceedings Mathematical Sciences》2007,117(3):387-399
We introduce certain linear positive operators and study some approximation properties of these operators in the space of
functions, continuous on a compact set, of two variables. We also find the order of this approximation by using modulus of
continuity. Moreover we define an rth order generalization of these operators and observe its approximation properties. Furthermore, we study the convergence
of the linear positive operators in a weighted space of functions of two variables and find the rate of this convergence using
weighted modulus of continuity. 相似文献
997.
T. Sasagawa 《Journal of Optimization Theory and Applications》1989,61(3):451-471
For the deterministic case, a linear controlled system is alwayspth order stable as long as we use the control obtained as the solution of the so-called LQ-problem. For the stochastic case, however, a linear controlled system with multiplicative noise is not alwayspth mean stable for largep, even if we use the LQ-optimal control. Hence, it is meaningful to solve the LP-optimal control problem (i.e., linear system,pth order cost functional) for eachp. In this paper, we define the LP-optimal control problem and completely solve it for the scalar case. For the multidimensional case, we get some results, but the general solution of this problem seems to be impossible. So, we consider thepth mean stabilization problem more intensively and give a sufficient condition for the existence of apth mean stabilizing control by using the contraction mapping method in a Hilbert space. Some examples are also given.This research was conducted while the author was a visitor at the Forschungsschwerpunkt Dynamische Systeme, Universität Bremen, Bremen, West Germany. The author is grateful to Professor L. Arnold for providing interesting seminars and excellent working conditions during his stay. The financial assistance given by the Alexander von Humboldt Foundation during the author's stay is also gratefully acknowledged. 相似文献
998.
In this paper, we study the rate of convergence for the iterative combinations of a certain family of linear positive operators in terms of higher-order integral modulus of smoothness. We have used the technique of linear approximating method, namely Steklov mean, to prove the main result. In the end, we propose some other sequences of linear positive operators and obtain the recurrence formulae for the central moments, Voronovskaja type asymptotic formulae and error estimations. 相似文献
999.
Harvey J. Greenberg 《Annals of Operations Research》1992,38(1):239-280
This paper describes a system to represent linear programming models and their instances. In addition to a modeling language, MODLER has an extensive query capability which includes a multi-view architecture. Further, randomization options provide rapid prototyping. The MODLER system is part of a workbench for building and managing decision support systems that are based on linear programming.This research was supported by a consortium of industries: Amoco Oil Company, Shell Development Company, Chesapeake Decision Science, GAMS Development Corp., Ketron Management Science, MathPro, Inc., Optimal Methods, Inc., and XMP Software, Inc. Partial support was also provided by the Office of Naval Research (Contract No. N-00014-88-K-0104). 相似文献
1000.
We shall present here results concerning the metric entropy of
spaces of linear and nonlinear approximation under very general conditions. Our
first result computes the metric entropy of the linear and m-terms
approximation classes according to a quasi-greedy basis verifying the
Temlyakov property. This theorem shows that the second index r is not visible
throughout the behavior of the metric entropy. However, metric entropy does
discriminate between linear and nonlinear approximation.
Our second result extends and refines a result
obtained in a Hilbertian framework by Donoho, proving that under orthosymmetry
conditions, m-terms approximation classes are characterized by the metric
entropy. Since these theorems are given under the general context of quasi-greedy
bases verifying the Temlyakov property, they have a large spectrum of
applications. For instance, it is proved in the last section that they can be
applied in the case of
L
p
norms for
R
d
for 1 < p < \infty.
We show that the lower bounds needed for this paper in fact follow
from quite simple
large deviation inequalities concerning hypergeometric or binomial distributions.
To prove the upper bounds, we provide a very simple universal coding
based on a thresholding-quantizing constructive procedure. 相似文献