动态绘制任意阶Bezier曲线的算法及其实现方法

介绍了如何利用VC 编程技术在图形系统中动态绘制任意阶Bezier工程曲线方法，并且使绘制的曲线具有捕捉、修改、动态增加型值点等功能。利用同样的方法，可以实现B样条、三次参数等其它工程曲线的绘制，从而扩大了Bezier等曲线的工程应用。     

双弹簧振子的振动分析

利用分析力学中的拉格朗日方程，推导出了双弹簧振子在小振幅情形下的非线性微分方程，并采用同伦摄动法解出了方程的一阶近似解及一阶近似周期，为工程应用提供了理论基础。     

Difference schemes on non-uniform mesh and their application

High order accurate schemes are needed to simulate the multi-scale complex flow fields to get fine structures in simulation of the complex flows with large gradient of fluid parameters near the wall, and schemes on non-uniform mesh are desirable for many CFD (computational fluid dynamics) workers. The construction methods of difference approximations and several difference approximations on non-uniform mesh are presented. The accuracy of the methods and the influence of stretch ratio of the neighbor mesh increment on accuracy are discussed. Some comments on these methods are given, and comparison of the accuracy of the results obtained by schemes based on both non-uniform mesh and coordinate transformation is made, and some numerical examples with non-uniform mesh are presented.     

Computer simulation for the precipitation process of Ni75Al7.5V17.5 alloy

The precipitation mechanism of Ni75Al7.5V17.5 alloy above the L12 instability line, between the L12 and D022 instability lines and below the D022 instability line are studied using microscopic phase-field kinetic equation. This paper is aimed at investigating the effect of temperature on precipitation mechanism and morphological evolution of the alloy. Our simulations demonstrate that the precipitation is a mixed mechanism of non-classical nucleation growth and spinodal decomposition above the L12 instability line. It needs certain thermal fluctuations for nucleation and the number of θ phases is small at this temperature. The precipitation mechanism of γ'phase is congruent ordering followed by spinodal decomposition, and θ phase is a mixed mechanism of non-classical nucleation growth and spinodal decomposition between the L12 and D022 instability lines. The mechanism below the D022 instability line is similar to that between the L12 and D022 instability lines. With the decrease of the temperature, ordering and phase separation becomes fast, the dimension of γ'phase becomes small, the shape transforms from equiaxed to block, the dimension of θ phase becomes large and the shape transforms from strip to circle.     

考虑质量风险时供应链订货批量的博弈分析

中间产品的质量缺陷给供应链的订货过程带来质量风险。提出了一种综合质量风险和采购库存成本的供应链订货批量模型,比较了考虑质量风险与不考虑质量风险时的供应链订货批量的差异。研究结果表明,无论在非合作还是在一体化的情况下,考虑质量风险时的订货批量都比不考虑质量风险时的批量小。     

一种运动目标提取方法及其应用

介绍了一种利用高阶统计量(higherorderstatistics,HOS)提取视频序列中运动目标的新方法,并将其应用到人脸识别技术中。利用HOS对高斯噪声的不敏感性分离运动区域和背景,进一步提取出运动目标。当提取出的视频序列中的运动对象为人体时,利用主元素分析法(principlecomponentanalysis,PCA)进行人脸识别。实验证明,算法计算简单,速度快,用于人脸识别时能正确提取出运动的人体。     

自适应OFDM系统中调制识别算法研究

提出了一种适用于快衰落信道下自适应OFDM系统的调制识别算法。在信道估计和频域补偿的基础上,利用子载波组样本的6阶和8阶累积量识别5种调制信号。仿真结果表明,该算法具有良好的识别性能和稳健性,在SNR=16 dB,移动台速度小于40 km/h的条件下,调制方式的正确识别率可在到95%以上。     

复杂性是随机性吗?

辨析了对柯尔莫哥洛夫复杂性的某些误读。指出柯尔莫哥洛夫复杂性定义下的随机性即序列的不可压缩性，不等于无序性，并且与传统的随机性理解相去甚远。在某些情况下，这种序列的不可压缩性恰恰是有序性的表现，从而说明，柯尔莫哥洛夫复杂性可以成为系统有序状态即复杂性的测度。     

关于熵、信息、序的五个佯谬

熵、信息、序的概念由来很久，准确理解和运用这些概念却往往被忽视。关于熵、信息、序的五个佯谬：信息既可以是有序的、又可是无序的；熵小必有序、熵大必无序；简单即有序、复杂即无序；信源熵等于信息量；混沌是高度复杂、高度有序的状态，源于对熵、信息、序概念的误解。准确把握熵、信息、序概念将使五个佯谬破解。     

Dirichlet级数的系数重排

研究了Dirichlet级数在系数重排后的增长性，分别得到了有限级Dirichlet级数的准确级和无限级Dirichlet级数的(R—H)级在级数系数重排后保持不变的条件．