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1.
ExampleofDocumentStyle\documentstyle[twoside,headrule]{article}%----------------------------------\oddsidemargin0truecm\evens...  相似文献   

2.
下面三个代数不等式互相等价:l.已知二、b、CeR牛,求ill:--------+--------+--------M——:(1〕h+r广十rsn+h一2(n+h十厂)’”一”2.(1963年莫斯科数学竞赛题)已知a。b、Ce矿,求证:--------+---------+----------MM;门)h十。广十co+h一J””一”3.(1988年第二届“友谊杯”试题)已知二、b、CER”,求证:--------+-----------+-------->;(。+h+f):h+f·t、+I7H+h一7”一(3)证明先证(l),由三元均值不等式可…  相似文献   

3.
广义a-结合BCI-代数   总被引:3,自引:0,他引:3  
引入了广义a-结合BCI-代数的概念,研究了BCI-代数的p-半单部分与广义a-结合部分的关系.并将p-半单BCI-代数的若干重要性质推广到广义a-结合BCI-代数上.最后我们证明了每个广义a-结合BCI-代数可确定一个交换偏序幺半群.本文结果表明文[1]的正则BCI-代数与p-半单BCI-代数是一致的.  相似文献   

4.
广义α—结合BCI—代数   总被引:3,自引:1,他引:2  
引入了广义α-结合BCI-代数的概念,研究了BCI-代数的p-半单部分与广义α-结合部分的关系。并将p-半单BCI-代数的若干重要性质推广到广义α-结合BCI-代数上。最后我们证明了每个广义α-结合BCI-代数可确定一个交换偏序幺半群。本文结果表明文[1]的正则BCI-代数与p-半单BCI-代数是一致的。  相似文献   

5.
数学问题解答1998年5月号问题解答(解答由问题提供人给出)1131试证:一元多项式P(x)=xk-xk-1-1的复根z=reiθ一定满足r2k-2r2k-1cosθ+r2k-2-1=0.证明我们有|P(z)||zk-zk-1|-1=rk-1|z-...  相似文献   

6.
1998年8月号问题解答(解答由问题提供人给出)1146.设xi∈R+,1≤i≤n,n≥2,∑ni=1xi=S.试证:∑ni=1xiS-xi≥nn-1S证明∵xiS-xi=SS-xi-S-xi=SS-xi+nn-1S-xi-2n-1n-1S-xi≥2...  相似文献   

7.
设R为环,t是左R-模范畴的一个遗传挠理论.文中证明了下述各点等价:(1)每个内射左R-模是t-平坦的;(2)每个t-有限表现左R-模的内射包络是t-平坦的;(3)每个t-有限表现左R-模是自由R-模的子模;(4)每个t-有限表现左R-模是自反的且其对偶模是H-有限生成的.  相似文献   

8.
万勇  宋鸿藻 《数学季刊》1998,13(4):103-105
§1. PreliminariesLetMbea(2n+1)-dimensionalcontactmetricmanifoldwithstructuretensors(Φ-,ξ-,η-,g).ThentheysatisfyΦ-ξ-=0,η-(ξ-)=1,Φ-2=-I+η-ξ-,η-(X)=g(X,ξ-),   g(Φ-X,Φ-Y)=g(X,Y)-η-(X)η-(Y),g(X,Φ-Y)=dη-(X,Y)(1.1)ForanyvectorfieldsXandY…  相似文献   

9.
文[1]曾指出一个流行题目:“已知a,b,α∈R,a,b同号且a>b,求证:a-ba+b≤a+bsinαa-bsinα≤a+ba-b.”是一道错题.然后将题目改为“已知:α∈R,a>b≥0,求证:a-ba+b≤a+bsinαa-bsinα≤a+ba-b. (※)其实,题目改后仍有失全面性和完整性.因为,当a<b≤0时,有-a>-b≥0,此时应用改后题目的结论(※)有:-a+b-a-b≤-a-bsinα-a+bsinα≤-a-b-a+b.进一步化简得:-(a-b)-(a+b)≤-(a+bsinα)…  相似文献   

10.
关于K—极凸Banach空间   总被引:3,自引:0,他引:3  
引进K-极凸Banach空间,证明了XK-极凸当且仅当X自反、K-严格凸且有(H)性质,得到了K-极凸空间的一些性质,并讨论了K-极凸与K-K-强光滑、K-一致凸及完全K-凸的关系。  相似文献   

11.
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  相似文献   

12.
该文讨论了Kolmogorov-Spieqel-Siveshinky方程的周期初值问题, 研究了半离散Fourier拟谱解的长时间行为, 证明了半离散系统的收敛性和整体吸引子的存在性. 构造了全离散的三层显式Fourier拟谱格式, 并证明了该格式的收敛性, 最后通过数值计算验证了格式的可信性. 数值结果表明: 该格式是长时间稳定并可取时间大步长. 作者模拟了方程的解在相空间的轨线, 得到了一些有意义的结论.  相似文献   

13.
基于Fuzzy等价关系的矩形聚类方法   总被引:2,自引:1,他引:1  
证明了Boole矩阵与模糊矩阵等价的充分必要条件,总结出Fuzzy聚类的矩形方法.针对《中国大学评价》中的6所林业院校,应用矩形方法,直接从模糊关系矩阵逐步降低阈值,得到分类的矩形表.此方法操作简单,形象直观,分类合理.  相似文献   

14.
Hidden Markov model is widely used in statistical modeling of time, space and state transition data. The definition of hidden Markov multivariate normal distribution is given. The principle of using cluster analysis to determine the hidden state of observed variables is introduced. The maximum likelihood estimator of the unknown parameters in the model is derived. The simulated observation data set is used to test the estimation effect and stability of the method. The characteristic is simple classical statistical inference such as cluster analysis and maximum likelihood estimation. The method solves the parameter estimation problem of complex statistical models.  相似文献   

15.
The reachability problem for linear time-invariant discrete-time control systems with sign-restricted input is considered. The time-optimal control is constructed by an iterative procedure. Each step of the iteration is defined as a linear programming problem. This problem is solved by the simplex algorithm. The initial feasible solution for the simplex algorithm is provided by the preceding step of the iteration. The inversion of the basis matrix is reduced to a bordering procedure. The structural stability of the solution is investigated.  相似文献   

16.
??Hidden Markov model is widely used in statistical modeling of time, space and state transition data. The definition of hidden Markov multivariate normal distribution is given. The principle of using cluster analysis to determine the hidden state of observed variables is introduced. The maximum likelihood estimator of the unknown parameters in the model is derived. The simulated observation data set is used to test the estimation effect and stability of the method. The characteristic is simple classical statistical inference such as cluster analysis and maximum likelihood estimation. The method solves the parameter estimation problem of complex statistical models.  相似文献   

17.
本文研究了证券市场中包含多个基金和股票时的均值-方差最优投资决策模型,得到了最优投资组合的解析表达形式,以及对应的投资有效前沿,证明了两基金分离问题,由于最优解是不唯一的,进而讨论了最优解集合的结构,并对实例进行计算与分析。  相似文献   

18.
本文分析了求解线性方程组的一维投影算法即最小剩余法。定义了长轴陷阱及陷阱深度,用它们刻划了该算法迭代过程中锯齿现象的几何特征。本文给出了基于残差序列的避开长轴陷阱的扰动技巧,即多维投影算法。数值试验表明,投影算法要优于现在流行的主要算法。  相似文献   

19.
A B-spline collocation method is presented for nonlinear singularly-perturbed boundary-value problems with mixed boundary conditions. The quasilinearization technique is used to linearize the original nonlinear singular perturbation problem into a sequence of linear singular perturbation problems. The B-spline collocation method on piecewise uniform mesh is derived for the linear case and is used to solve each linear singular perturbation problem obtained through quasilinearization. The fitted mesh technique is employed to generate a piecewise uniform mesh, condensed in the neighborhood of the boundary layers. The convergence analysis is given and the method is shown to have second-order uniform convergence. The stability of the B-spline collocation system is discussed. Numerical experiments are conducted to demonstrate the efficiency of the method.  相似文献   

20.
The onset of Marangoni convection in a non-reactive binary fluid layer in the presence of throughflow and Soret effect is determined. The bottom boundary of the fluid layer is assumed to be either conducting or insulating to temperature and solute concentration perturbations while the top boundary is free and insulating. The linear stability analysis is followed and an exact solution is obtained for the corresponding eigenvalue problem by assuming that stationary convection is exhibited at the neutral state. The contribution from the Soret effect is seen only when the throughflow is weak, but however for a wider range of upward throughflow when the bottom boundary is conducting. The instability gets advanced/delayed when the Soret parameter assumes negative/positive values. The results agree well with the existing results in the literature for some particular cases.  相似文献   

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