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1.
Extensions of Vietoris''s Inequalities (Ⅱ)   总被引:1,自引:0,他引:1  
It was shown by Vietoris[1] in 1958 that for n ≥ 1 and x ∈ (0, π), n∑k=0ckcos(kx)>0,(1)  相似文献   

2.
In 1958, L. Vietoris[10] proved that if α0 ≥ αl ≥ ... ≥ αn ≥ 0 and α2k ≤ (1-1/2k)α2k-1, k ≥ 1,then for n ≥ 1 and θ ∈ (O, π),  相似文献   

3.
It was shown by Vietoris in 1958 that for n≥ 1 and x ∈(0,π),  相似文献   

4.
Excellent Extensions of RingsLiuZhongkui(刘仲奎)andWangTingZhen(王廷桢)(DepartmentofMathcmatics,NorthwestNormalUniversity,Lanzhon,7...  相似文献   

5.
Let S be an excellent extension of a ring R and U a flat right 5-module. We show in this paper that the left (N, U)-coherent dimension of S is equal to that of R.  相似文献   

6.
We introduce the category of t-fold modules which is a full subcategory of graded modules over a graded algebra. We show that this subcategory and hence the subcategory of t-Koszul modules are both closed under extensions and cokernels of monomorphisms. We study the one-point extension algebras, and a necessary and sufficient condition for such an algebra to be t-Koszul is given. We also consider the conditions such that the category of t-Koszul modules and the category of quadratic modules coincide.  相似文献   

7.
TheNewSeriesofLA-Groups(Ⅰ)班桂宁,李世余,张劲松TheNewSeriesofLA-Groups(Ⅰ)¥Bangining;LiShiyu;ZhangJinsong(MathsDept.,GuangXiUniversity,N...  相似文献   

8.
Several Inequalities of Matrix Traces   总被引:2,自引:0,他引:2  
SeveralInequalitiesofMatrixTraces¥ChenHongqing(HainanNormalCollege)Abstract:Thispaperhasmadetheresultofgeneralizationandthean...  相似文献   

9.
The technique described in [9] is used to discuss the sensitivity of multiple eigenvalues and corresponding eigenspaces of symmetric eigenproblems analytically dependent to several parameters. The results may be useful for investigating problems of stability and response analysis of linear structures.  相似文献   

10.
卢博 《数学季刊》2012,(1):128-132
Let R be a noetherian ring and S an excellent extension of R.cid(M) denotes the copure injective dimension of M and cfd(M) denotes the copure flat dimension of M.We prove that if M S is a right S-module then cid(M S)=cid(M R) and if S M is a left S-module then cfd(S M)=cfd(R M).Moreover,cid-D(S)=cid-D(R) and cfd-D(S)=cfdD(R).  相似文献   

11.
Niushan Gao 《Positivity》2013,17(4):965-977
The classical Perron–Frobenius theory asserts that, for two matrices $A$ and $B$ , if $0\le B \le A$ and $r(A)=r(B)$ with $A$ being irreducible, then $A=B$ . It has been extended to infinite-dimensional Banach lattices under certain additional conditions, including that $r(A)$ is a pole of the resolvent of $A$ . In this paper, we prove that the same result holds if $B$ is irreducible and $r(B)$ is a pole of the resolvent for $B$ . We also prove some other interesting extensions of the theorem for infinite-dimensional Banach lattices.  相似文献   

12.
We give an explicit Dirichlet series for the generating function of the discriminants of quartic dihedral extensions of . From this series we deduce an asymptotic formula for the number of isomorphism classes of such quartic extensions with discriminant up to a given bound. On the other hand, by using essentially classical results of genus theory combined with elementary analytical methods such as the method of the hyperbola, we show how to compute exactly this number up to quite large bounds, and we give a table of selected values.  相似文献   

13.
We study into questions that naturally arise when Prüfer rings are viewed from the geometry standpoint. A ring of principal ideals which has infinitely many prime ideals and is such that its field of fractions is non-Hilbertian is constructed. This answers in the negative a question of Lang.  相似文献   

14.
C. A. Carvalho 《代数通讯》2013,41(8):2871-2886
We first consider the class of monoids in which every left invertible element is also right invertible, and prove that if a monoid belonging to this class admits a finitely presented Bruck–Reilly extension then it is finitely generated. This allow us to obtain necessary and sufficient conditions for the Bruck–Reilly extensions of this class of monoids to be finitely presented. We then prove that thes 𝒟-classes of a Bruck–Reilly extension of a Clifford monoid are Bruck–Reilly extensions of groups. This yields another necessary and sufficient condition for these Bruck–Reilly extensions to be finitely generated and presented. Finally, we show that a Bruck–Reilly extension of a Clifford monoid is finitely presented as an inverse monoid if and only if it is finitely presented as a monoid, and that this property cannot be generalized to Bruck–Reilly extensions of arbitrary inverse monoids.  相似文献   

15.
We consider a class of strongly coupled and strongly degenerate systems of par-tial differential equations of the form Z_t= [g_1(Z)∧ g_2(Z)∧…∧g_(n-2) (Z)∧△Z] + f(x,t,Z), (1)where Z = (Z_1, Z_2,…, Z_n) (n≥2) is the n-dimensional unknown vector funetion of  相似文献   

16.

Popoviciu’s inequality is extended to the framework of h-convexity and also to convexity with respect to a pair of quasi-arithmetic means. Several applications are included.

  相似文献   

17.
Let β 0=0.308443… denote the Littlewood-Salem-Izumi number, i.e., the unique solution of the equation
In this paper it is proved that if a 0a 1⋅⋅⋅a n >0 and , k≥1 then for all θ∈(0,π)
and furthermore, the number β 0 is best possible in the sense that for any β∈(0,β 0)
where the coefficients c k (β) are defined as
Results for the sine sums are obtained as well. These results generalize and sharpen the well known trigonometric inequalities of Vietoris. This research was supported by a grant from the Australian Research Council. The second author was also supported in part by the NSERC Canada under grant G121211001. The third author was also supported in part by the NSFC of China under grant 10471010.  相似文献   

18.
The Evaluation of Basic Hypergeometric Series(Ⅰ)   总被引:1,自引:0,他引:1  
TheEvaluationofBasicHypergeometricSeries(Ⅰ)ZhangXiangde(NortheasternUniversity,Shenyang110006)TaoChangqi(JiangxiInstituteofFi...  相似文献   

19.
聚类分析(Ⅰ)   总被引:5,自引:0,他引:5  
聚类分析(Cluster Analysis)是数理统计中研究“物以类聚”的一种方法,近十年来发展很快,从数值分类学中独立出来成为专门的分枝,并且在地质勘探、天气预报、生物分类、考古学、医学、心理学以及制定国家标准等许多方面都取得了许多很有成效的应用.由于聚类分析的方法简单有效,近年来引起了各方面对它的重视,有关的专著陆续出了几本,如参考资料[3,4]等;有些杂志连载了这个方法的讲座,如[7]等.聚类分析和数理统计传  相似文献   

20.
可靠性(Ⅰ)     
§1.什么叫可靠性 可靠性工程研究的是:产品从研制、生产、使用各个环节中应采取的有关可靠性的技术措施.其目的为:保证产品达到预定的可靠性指标.通过试验及实践,发现产品的薄弱环节及导致薄弱的主要内外因素;掌握这些薄弱环节之所以薄弱的物理、化学、生理机理及其统计规律;采取相应的技术措施,改进、提高产品的可靠性.  相似文献   

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