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761.
孙培源 《纯粹数学与应用数学》1999,15(4):42-45
证明文[3]中的若干定理的交换性要求可以去掉.主要结论是:若X是有界BCK代数,D是X的对偶理想,一定存在从DI(X,D)到DI(XD)的一一对应 相似文献
762.
《中国化学快报》2020,31(7):1827-1830
Robust normalization is a prerequisite for reliable metabonomic analysis especially when intervention treatments cause drastic metabolomic changes or when spot urinary samples are employed without knowing the drinking water quantity. With the simulated and real datasets, here, we report a probabilistic quotient normalization method based on the mode-of-quotients (mPQN) which is suitable for metabonomic analysis of both NMR and LC–MS data with little and/or drastic metabolite changes. When applied to metabonomic analysis of both animal plasma samples and human urinary samples, this newly proposed method has clearly shown better robustness than all classical normalization methods especially when drastic changes of some metabolites occur. 相似文献
763.
764.
SUN JiaChang 《中国科学 数学(英文版)》2014,57(2):221-244
With an error compensation term in the fractal Rayleigh quotient of PDE eigen-problems,we propose a new scheme by perturbing the mass matrix Mhto Mh=Mh+Ch2mKh,where Khis the corresponding stif matrix of a 2m 1 degree conforming finite element with mesh size h for a 2m-order self-adjoint PDE,and the constant C exists in the priority error estimationλh jλj~Ch2mλ2j.In particular,for Laplace eigenproblems over regular domains in uniform mesh,e.g.,cube,equilateral triangle and regular hexagon,etc.,we find the constant C=I h 1Mh2 hKh and show that in this case the computation accuracy can raise two orders,i.e.,fromλh jλj=O(h2)to O(h4).Some numerical tests in 2-D and 3-D are given to verify the above arguments. 相似文献
765.
766.
Walter Roth has investigated certain equivalence relations on locally convex cones in [W. Roth, Locally convex quotient cones, J. Convex Anal. 18, No. 4, 903–913 (2011)] which give rise to the definition of a locally convex quotient cone. In this paper, we investigate some special equivalence relations on a locally convex lattice cone by which the locally convex quotient cone becomes a lattice. In the case of a locally convex solid Riesz space, this reduces to the known concept of locally convex solid quotient Riesz space. We prove that the strict inductive limit of locally convex lattice cones is a locally convex lattice cone. We also study the concept of locally convex complete quotient lattice cones. 相似文献
767.
Fibonacci三角形是边长为Fibonacci数、面积为整数的三角形.利用平方剩余的方法得到:当k=2'·3时,不存在边长为(Fn-k,Fn,Fn)的Fibonacci三角形(k<2). 相似文献
768.
In this paper,we consider infinite sums of the reciprocals of the Fibonacci numbers.Then applying the floor function to the reciprocals of this sums,we obtain a new identity involving the Fibonacci numbers. 相似文献
769.
研究广义费波那契序列通项公式的计算方法.利用整系数多项式正根理论,得到了广义费波那契序列通项的一个十分精确的近似计算方法. 相似文献
770.
Mei-Qin Zhan 《Journal of Mathematical Analysis and Applications》2011,380(2):831-846
The selective decay phenomena have been observed by physicists for many dynamic flows such as Navier-Stokes flows, barotropic geophysical flows, and magnetohydrodynamic (MHD) flows in either actual physical experiments or numerical simulations. In the previous paper (M.-Q. Zhan, 2010 [20]), the author showed the validity of the selective decay principle for the 2D magnetohydrodynamic (MHD) flows in the case of small magnetic Prandtl number. In this paper, we shall show the validity of the selective decay principle for the 2D magnetohydrodynamic (MHD) flows for any magnetic Prandtl number with periodic boundary conditions. 相似文献