完整系统三阶Lagrange方程的一种推导与讨论

从牛顿运动方程出发，推导了完整系统关于广义加速度的Lagrange方程.讨论了该方程与传统分析力学中的Lagrange方程的相容性问题.结果显示，三阶Lagrange方程可以通过对Lagrange方程求一阶时间导数得到，表明它们是相容的.因此三阶Lagrange方程提供了一种不同于传统Lagrange方程方法的求解物体运动方程的途径.     

完整系统三阶Lagrange方程的一种推导与讨论

从牛顿运动方程出发,推导了完整系统关于广义加速度的Lagrange方程.讨论了该方程与传统分析力学中的Lagrange方程的相容性问题.结果显示,三阶Lagrange方程可以通过对Lagrange方程求一阶时间导数得到,表明它们是相容的.因此三阶Lagrange方程提供了一种不同于传统Lagrange方程方法的求解物体运动方程的途径.     

几种广义非线性发展方程的新解

本文研究了构造了广义Kd V方程和广义KP-Burgers方程等几种广义非线性发展方程的新解的问题.利用三种辅助方程及其新解,获得了广义Kd V方程和广义KP-Burgers方程等几种广义非线性发展方程的新解.这些解由双曲余割函数、双曲正切函数、双曲正割函数、双曲余切函数和余割函数组成.     

非等谱散焦非线性Schrdinger方程的规范变换和精确解

非线性Schrdinger方程及其相关方程在许多领域都得到广泛应用.为了研究谱参数随时间变化时散焦非线性Schrdinger方程的性质,研究了三个非等谱散焦非线性Schrdinger方程.对于前两个方程,给出了它们与等谱方程之间的规范变换,以及多孤子精确解.对于第三个方程给出了单孤子解.     

耦合Gerdjikov-Ivanov方程的多孤子解和无穷守恒律

借用Hirota方法找到耦合Gerdjikov-Ivanov方程的多孤子解.描述了单孤子解和双孤子解的动力特征.耦合Gerdjikov-Ivanov方程可约化至Gerdjikov-Ivanov方程,并且得出Gerdj ikov-Ivanov方程的解.还给出了耦合Gerdj ikov-Ivanov方程的无穷多守恒律.     

三维重调和方程的双方程边界积分方程法

以守恒积分为工具,推导了三维重调和方程的新的边界积分方程,所得出的新方程与传统的边界积分方程相比较,降低了奇异性,避免了传统边界元方法中的强奇异积分的计算.对不同边界都采用第二类积分方程,得到了三维重调和方程的双方程方法.     

模糊Logistic方程的稳定性

研究了具有广义Hukuhara导数的模糊Logistic方程,将模糊Logistic方程转化成两个常微分方程,分析了模糊Logistic方程平衡点的稳定性.结论表明,模糊Logistic方程平衡点的稳定性不同于确定的Logistic方程,丰富了模糊微分方程研究的内容.     

一类非线性发展方程的显式精确解

提出了寻求非线性发展方程行波解新的辅助方程法,作为实例通过选取变系数Bernoulli方程作为辅助常微分方程,并借助于计算机系统Mathematica和齐次平衡原则,求解了一类非线性发展方程,得到了该方程的新的显式精确解.所用方法可应用到其它类似方程的求解.     

学会方程思想方法

<正>所谓方程思想方法,就是以方程的视角审视问题,通过建立相关的方程来解决问题的思想方法.由于方程思想方法贯穿了高中数学,因此加深对方程思想方法的理解掌握,提高运用方程思想方法解决问题能力,是学好高中数学的重要方面.本文拟从三个方面就如何学会方程思想方法,向同学们提出建议,供参考.一、增强方程意识所谓方程意识,即是运用方程角度看问题的意识.增强方程的意识,就是要养成一种当     

一类Camassa-Holm型方程的不变子空间及其精确解

研究一类三阶CH型方程的解的问题.利用不变子空间理论,讨论了方程在不同参变量取值情况下所允许的不变子空间,从而得出了此类方程的两个特殊的精确解.所得结果不仅描述了该方程的一些特性,而且丰富了文献中关于此类CH型方程的内容.     

Integrating design problems in mathematics curriculum: an architecture college case study

This paper reports an attempt to improve results in the mathematics course in one of the architecture colleges in Israel through practise in applications. The effect of integrating structure design problems in the calculus curriculum on students' achievements and attitudes was examined. The applied topics in the curriculum were connected to calculus topics and studied through problembased learning activities. The integrated curriculum was implemented and the learning results in experimental and control groups were assessed by means of achievement tests, attitude questionnaires and student interviews. The learning achievements in the experimental group proved to be significantly higher than in the control group. The positive impact of learning applications on motivation, understanding, creativity and interest in mathematics is indicated.     

基于IAHP-Entropy集成确权的煤炭企业可持续发展综合评价

结合煤炭企业实际,提出了煤炭企业可持续发展的指标体系。应用区间判断层次分析法（IAHP）的理论与方法,结合熵理论（Entropy）,建立了主观与客观集成确权的IAHP—Entropy综合评价模型。该方法既能有效避免单一主观确权的人为随意性,又能克服单一客观确权无法反映专家经验和决策者偏好的缺点。通过将该模型的应用,验证了该方法的科学性和实践可行性。     

Nash and Stackelberg Differential Games

A large class of stochastic differential games for several players is considered in this paper.The class includes Nash differential games as well as Stackelberg differential games.A mix is possible.The...     

The Effect of Dispersal on Population Growth with Stage-structure

The effect of dispersal on the permanence of population in a polluted patch is studied in this paper. The authors constructed a single-species dispersal model with stage-structure in two patches. The analysis focuses on the case that the toxicant input in the polluted patch has a limit value. The authors derived the conditions under which the population will be either permanent, or extinct.     

基于混沌的三江平原月降水时间序列分析

三江平原是我国最大的淡水沼泽区,近年来降水的减少是导致湿地减少的一个重要的自然因素.别拉洪河是三江平原上比较有代表性的沼泽性河流.以别拉洪水文站的降水序列为例,通过相空间重构,分别计算了序列的关联维、最大Lyapunov指数以及Kolmogorov熵等几个序列特征量.计算表明:三江平原月降水序列中是存在明显的混沌特征的,这为以后建立三江平原月降水的混沌预测模型提供了理论依据.     

Non-linear peristaltic transport of a second-order fluid through a porous medium

The present paper investigates phenomena brought about into the classic peristaltic mechanism by inclusion of non-Newtonian effects through a porous space in a channel. The peristaltic motion of a second-order fluid through a porous medium was studied for the case of a planar channel with harmonically undulating extensible walls. The system of the governing nonlinear PDE is solved by using the perturbation method to second-order in dimensionless wavenumber. The analytic solution has been obtained in the form of a stream function from which the axial pressure gradient has been derived. The flow is investigated in a wave frame of reference moving with velocity of the wave. Numerical calculations are carried out for the pressure rise and frictional force. The features of the flow characteristics are analyzed by plotting graphs and discussed in detail.     

Intermediate asymptotics for solutions to the degenerate principal resonance equations

The system of two first-order differential equations that arises in averaging nonlinear systems over fast single-frequency oscillations is investigated. The averaging is performed in the neighborhood of the critical free frequency of a nonlinear system. In this case, the original equations differ from the principal resonance equations in the general case. The main result is the construction of the asymptotics of a two-parameter family of solutions in the neighborhood of a solution with unboundedly increasing amplitude. The results, in particular, provide a key to understanding the particle acceleration process in relativistic accelerators near the critical free frequency.     

“小麦发育后期茎秆抗倒性的数学模型”综述

2011年第8届全国研究生数学建模竞赛C题是一个农业生产中小麦倒伏问题,在给出3年原始测量数据的基础上要求建立小麦发育后期茎秆抗倒性的数学模型,内容包括小麦性状数据处理和弹性力学模型.综述为C题竞赛总结,含问题的提出、问题的解答与评阅情况、存在问题及研究建议.     

Laplace方程有孔椭圆区域边值问题的解析解

本文利用相似流动替换方法 ,解决了中心有圆孔的椭园形区域上 Laplace方程第一类边值问题 ;采用分区域解法 ,给出了中心有椭园孔的椭园形区域上 Laplace方程第一类边值问题的解析通解 .这一结果在许多工程领域有重要应用 ,本文给出了油藏工程实例     

Stimulating student aesthetic response to mathematical problems by means of manipulating the extent of surprise

We investigated aesthetic responses of 60 middle school students as they engaged in a pair of similar looking geometry problems in one-on-one semi-structured interviews. The investigation was driven by three predictions. The first two predictions were about the association between the evaluative aesthetic response and surprise stemming from the solution to each problem. The third, main, prediction was that the problem with more surprising solution would be evaluated as more beautiful. The extent of surprise was manipulated by the order in which two problems were given. The third prediction came to be true in 90% of the cases, in which the first two predictions were fulfilled. The findings suggest that school students’ evaluative aesthetic response to mathematical problems can be stimulated in instructional settings. Implications for research and practice are drawn.