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1.
本文建立非线性非完整系统相对于非惯性系动力学的积分理论.首先,由这种相对运动的Routh方程给出系统的第一积分;其次,分别利用系统的循环积分、能量积分降阶运动方程,得到推广的Routh方程和推广的Whittaker方程;再次,建立这类系统运动的正则方程和变分方程,并由第一积分构造系统的积分不变量;然后,给出系统的Poincare-Cartan型积分变量关系和积分不变量.最后,给出一系列推论.  相似文献   

2.
非线性非完整系统Vacco动力学方程的积分方法*   总被引:3,自引:0,他引:3  
本文给出积分非线性非完整系统Vacco动力学方程的积分方法.首先,将Vacco动力学方程表示为正则形式和场方程形式;然后,分别用梯度法,单分量法和场方法积分相应完整系统的动力学方程,并加上非完整约束对初条件的限制而得到非线性非完整系统Vacco动力学方程的解.  相似文献   

3.
正1 引言随机积分方程在工程、生物学、海洋学、物理学等领域有着广泛的应用,用其对随机现象进行建模变得越来越重要.由于系统的多样性和不同噪声影响,多种形式的随机方程都用于系统建模.其中,随机Volterral积分方程广受关注.然而,许多随机Volterra积分方程不存在精确解,因此对随机Volterra积分方程寻求较高精度的数值解是有意义的.目前,随机Volterra积分方程有不同的数值解法,如正交基法[4,6-11,13,14,16-18],Wash级数法[2,3],多项式法[1,5,12,15,19,20]等.  相似文献   

4.
提出了一种利用模糊系统求解非线性Fredholm-Ⅱ积分方程解析解的方法:首先将积分方程转化为模糊系统,然后利用具有紧支集和正规性的尺度函数构造模糊基函数和积分方程的模糊解,最后构造能量误差函数,通过最小化误差函数学习模糊系统的参数.数值实验表明:用模糊系统求得的便于运算的解析解比用Galerkin方法求得的数值解精度高.  相似文献   

5.
本文给出积分变质量非线性非完整系统相对于非惯性系动力学方程的梯度法,单分量法和场方法。首先,将这类问题的动力学方程表示为正则形式和场方程形式;然后,分别用梯度法,单分量法和场方法积分相应常质量完整系统相对于惯性系的动力学方程,并加上非完整约束对初始条件的限制而得到变质量非线性非完整系统相对于非惯性系动力学方程的解。  相似文献   

6.
空气动力学中出现的某些混合型偏微分方程组的边值问题往往归结为带非Carleman位移的奇异积分方程。关于带Carleman位移的线性奇异积分方程已有系统理论。可见专著和文献等。而关于带非Carleman位移的奇异积分方程的理论目前还很不完整。专著介绍了一些结果。 本文研究带位移的拟线性奇异积分方程  相似文献   

7.
本文给出高阶非完整系统运动方程的一类积分及其存在条件,包括1阶积分(广义能量积分),2阶积分和p(p>2)阶积分,所有这些积分都可按系统的Lagrange函数来构造.举例说明本文方法的应用.  相似文献   

8.
相对论性Birkhoff系统的变分方程与积分不变量   总被引:2,自引:0,他引:2       下载免费PDF全文
建立了相对论性Birkhoff系统的变分方程,并且利用系统的Birkhoff方程及其变分方程证明了可由第一积分直接构造该系统的一类积分不变量。文中举例说明了结果的应用。  相似文献   

9.
带Hilbert核的奇异积分方程的数值解法   总被引:8,自引:0,他引:8  
杜金元 《计算数学》1989,11(2):148-166
作者在[1—4]中巳经系统讨论了带Cauchy核的奇异积分方程的数值解法.本文考虑带Hilbert核的奇异积分方程  相似文献   

10.
转动系统相对论性动力学方程的代数结构与Poisson积分   总被引:7,自引:1,他引:6  
研究转动相对论系统动力学方程的代数结构,得到了完整保守转动相对论系统与特殊非完整转动相对论系统动力学方程具有Lie代数结构;一般完整转动相对论系统、一般非完整转动相对论系统动力学方程具有Lie容许代数结构。并给出转动相对论系统动力学方程的Poisson积分。  相似文献   

11.
In this paper, an adaptive method for sampling and reconstructing high‐dimensional shift‐invariant signals is proposed. First, the integrate‐and‐fire sampling scheme and an approximate reconstruction algorithm for one‐dimensional bandlimited signals are generalized to shift‐invariant signals. Then, a high‐dimensional shift‐invariant signal is reduced to be a sequence of one‐dimensional shift‐invariant signals along the trajectories parallel to some coordinate axis, which can be approximately reconstructed by the generalized integrate‐and‐fire sampling scheme. Finally, an approximate reconstruction for the high‐dimensional shift‐invariant signal is obtained by solving a series of stable linear systems of equations. The main result shows that the final reconstructed error is completely determined by the initial threshold in integrate‐and‐fire sampling scheme, which is generally very small. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

12.
配送量不定的供应链协调   总被引:3,自引:0,他引:3  
本文研究供应链管理中配送量不确定时,制造商和分销商之间的协调问题。通过建立惩罚和奖励机制模型来协调供应链各部分的运作,使得分散系统就如一个整体。同时分析供应链的利润分配问题,分别得出各个机制下分销商的最优决策。  相似文献   

13.
The choice of a Contract Research Organisation (CRO-Sponsor partnership or CRO) in clinical development is fundamental for the medical department of a pharmaceutical company. A decision analysis tool can help in this choice. Multicriteria analysis (ELECTRE 1 and 2) has the capacity to integrate qualitative judgement criteria with weights in incorporating the concordance and discordance indexes. The objective of this study is to present the theory and one application in the selection of CROs. How can one CRO be selected from a group of nine pre-selections by using seven judgement criteria with different weights? The results in this paper are: with the ELECTRE 1 method six CROs were selected and only one CRO with the ELECTRE 2 method.  相似文献   

14.
We use the discriminantly separable polynomials of degree 2 in each of three variables to integrate explicitly the Sokolov case of a rigid body in an ideal fluid and integrable Kirchhoff elasticae in terms of genus 2 theta functions. The integration procedure is a natural generalization of the one used by Kowalevski in her celebrated 1889 paper. The algebraic background for the most important changes of variables in this integration procedure is associated to the structure of the two-valued groups on an elliptic curve. Such two-valued groups have been introduced by V.M. Buchstaber.  相似文献   

15.
The Role of Quantity Discounts in the Presence of Heterogeneous Buyers   总被引:8,自引:0,他引:8  
In this paper we develop a model to examine the role of quantity discounts in synchronizing production and order cycles for a system consisting of one manufacturer and two heterogeneous buyers. The model developed can serve as a guideline for the manufacturer and the buyers as how to integrate their decisions to achieve higher benefits. The numerical examples indicate that the benefit of synchronization decreases with the degree of heterogeneity of the buyers. The conditions under which it is profitable for the manufacturer to synchronize with the heterogeneous buyers are demonstrated through numerical examples.  相似文献   

16.
土壤是一个多性状的连续体,其分类的首选方法是模糊聚类分析.但是模糊聚类分析中现有的基于模糊等价关系的动态聚类法和模糊c-均值法各有利弊,采用其中一种方法聚类肯定存在不足.为此集成两种聚类方法的优点,避其缺点,提出了用基于模糊等价关系的动态聚类方法和方差分析方法确定聚类数目和初始聚类中心,再用模糊c-均值法决定最终分类结果的集成算法,并将其应用到松花江流域土壤分类中,得到了较为切合实际的分类结果.  相似文献   

17.
This paper introduces an extension of the classical BDF formulae, which integrate, without local truncation error, homogeneous linear ODEs with constant coefficients. In particular, they integrate exactly scalar linear equations whose characteristics roots have a large stiffness ratio.  相似文献   

18.
When there are multiple trained predictors, one may want to integrate them into one predictor. However, this is challenging if the performances of the trained predictors are unknown and labeled data for evaluating their performances are not given. In this paper, a method is described that uses unlabeled data to estimate the weight parameters needed to build an ensemble predictor integrating multiple trained component predictors. It is readily derived from a mathematical model of ensemble learning based on a generalized mixture of probability density functions and corresponding information divergence measures. Numerical experiments demonstrated that the performance of our method is much better than that of simple average-based ensemble learning, even when the assumption placed on the performances of the component predictors does not hold exactly.  相似文献   

19.
The multi-criteria scheduling problem is one of the main research subjects in the field of multiple objectives programming. Several procedures have been developed to deal with this type of problem where some conflicting criteria have to be optimized simultaneously. The aim of our paper is to propose an aggregation procedure that integrates three different criteria to find the best sequence in a flow shop production environment. The compromise programming model and the concept of satisfaction functions will be utilized to integrate explicitly the manager’s preferences according to the deviations between the achievement and the aspiration levels of the following criteria: Makespan, total flow time and total tardiness.  相似文献   

20.
Gauss-type quadrature rules with one or two prescribed nodes are well known and are commonly referred to as Gauss–Radau and Gauss–Lobatto quadrature rules, respectively. Efficient algorithms are available for their computation. Szeg? quadrature rules are analogs of Gauss quadrature rules for the integration of periodic functions; they integrate exactly trigonometric polynomials of as high degree as possible. Szeg? quadrature rules have a free parameter, which can be used to prescribe one node. This paper discusses an analog of Gauss–Lobatto rules, i.e., Szeg? quadrature rules with two prescribed nodes. We refer to these rules as Szeg?–Lobatto rules. Their properties as well as numerical methods for their computation are discussed.  相似文献   

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