首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
3.
平面凸体的完全不等式组   总被引:1,自引:1,他引:0  
李德宜  杨宣  谢鹏 《数学杂志》2005,25(1):49-52
对于平面凸体,分别用A、p、r、R、d表示它的面积、周长、内径、外径、直径.本文分别给出了其中的三元组合(A,r,R),(p,r.R),(p,r,d),(A,r,d)所满足的不等式,并给出了相应的极值集.  相似文献   

4.
半质环的交换性条件   总被引:2,自引:0,他引:2  
傅昶林  郭元春 《数学学报》1995,38(2):242-247
本文对满足可变恒等式的半质环在某种有界条件下给出了一个判断环R交换性的简便准则,使文献[2-27]中所有相应结果均成为其直接推论.此外,对不限有界的情况,也得到较为广泛的结论.  相似文献   

5.
We consider the three dimensional Cauchy problem for the Laplace equation uxx(x,y,z)+ uyy(x,y,z)+ uzz(x,y,z) = 0, x ∈ R,y ∈ R,0 z ≤ 1, u(x,y,0) = g(x,y), x ∈ R,y ∈ R, uz(x,y,0) = 0, x ∈ R,y ∈ R, where the data is given at z = 0 and a solution is sought in the region x,y ∈ R,0 z 1. The problem is ill-posed, the solution (if it exists) doesn't depend continuously on the initial data. Using Galerkin method and Meyer wavelets, we get the uniform stable wavelet approximate solution. Furthermore, we shall give a recipe for choosing the coarse level resolution.  相似文献   

6.
给出了最佳参数α_1,α_2,α_3,β_1,β_2,β_3∈R,使得双向不等式α_1Q(a,b)+(1-α_1)G(a,b)0且a≠b成立.其中A(a,b)=(a+b)/2,H(a,b)=2ab/(a+b),G(a,b)=(ab)~(1/2),Q(a,b)=((a~2+b~2)/2)~(1/2),C(a,b)=(a~2+b~2)/(a+b),T(a,b)=2/π∫_0~(π/2)(a~2cos~2t+b~2sin~2)~(1/2)tdt分别是两个正数a和b的算术平均,调和平均,几何平均,二次平均,反调和平均和Toader平均.  相似文献   

7.
BOOK REVIEWS     
Book reviewed in this article: The Origin of the Carolina Bays , by Douglas Johnson. A Guide to Naval Aviation , by Lt. Wallace W. Elton, USNR; Lt. Alfred H. Driscoll, USNR; Lt. Robert N. Burchmore, USNR; and Lt. Gray B. Larkum, USNR. Mathematics for Navigators , by Delwyn Hyatt, Commander, USN, (Ret.) and Bennett M. Dodson, Commander, USNR. The Text -Activity Books . Elementary Topography and Map Reading , by Samuel L. Greitzer. Earth Science , A Physiography, by Gustave L. Fletcher. Shopwork , by Edward C. Wicks, Instructor of Industrial Arts, Morristown High School, New Jersey, John Poljacik, Jr., Instructor of Industrial Arts, Morrislown High School, and John Ellberg, author of Tales of A Rambler. Shop Practice , by William J. Kennedy. Plane Trigonometry and Statics , by Norman Miller. The Story of Flying , by Archibald Black. Electricity for Everyone , by Joseph R. Lunt, late Professor of Science at Rhode Island College of Education, and William T. Wyman. Air Navigation for Beginners , A Ground School Primer for Aerial Navigators , by Scott G. Lamb, B.S., M.S. Essentials of Algebra (Complete Second Year Course ), by Walter W. Hart. Solid Geometry , by F. Eugene Seymour, Supervisor of Mathematics, New York State Department of Education, and Paul James Smith, Head of Department of Mathematics, East High School, Rochester, New York. Modern Science Series , by Charles E. Dull. Organic Chemistry , by C. W. Porter and T. D. Stewart. Man's Physical Universe , by Arthur Talbot Bawden. Man and His Physical Universe , by Frank Covert, Jean Ezra Clarence Harrah, and Fred Louis Herman. Elementary Electricity , by Edgar P. Slack.  相似文献   

8.
在这篇注记中我们讨论随机变量的一致可积性.在概率空间中,我们引进了随机变量一致可积性的两个新的定义,并证明了他们与经典定义等价.在次线性期望空间中,我们给出了随机变量一致可积性的德拉瓦利普桑准则,并作了一些其它讨论.  相似文献   

9.
10.
摘要:设n是正整数;P_0=1,P_i(i=1,2,…)是第i个素数.本文证明了:方程 n!+1=P_k~aP_(k+1)~b,P_(k-1)0,b>0,仅有解(n,P_k,P_(k+1),a,b)=(1,1,2,1,0),(2,3,5,1,0),(3,5,7,0,1),(4,5,7,2,0),(5,7,11,0,2).上述结果证实了Erds和Stewart提出的一个猜想.  相似文献   

11.
The Ramanujan Journal - The 15 primes 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 41, 47, 59, 71 are called the supersingular primes: they occur in several contexts in number theory and also,...  相似文献   

12.
如果两个v阶拉丁方L和M的重叠产生恰好r个不同的有序对,则称L和M是r-正交的.如果L还是M的(i,j,k)-共轭,则称L是(i,j,k)-共轭r-正交的,简记为(i,j,k)-r-COLS(v)((i,j,k)-r-conjugate orthogonal Latin square of order v),其中{i,j,k}={1,2,3}.本文研究(3,2,1)-r-COLS(v)的存在性问题.对于v 23,除去少数几个可能的例外值,本文给出关于(3,2,1)-r-COLS(v)的几乎完整的解.对于v23,如果r∈[v,v2]\{v+1,v+2,v+3,v+5,v+7,v2 1},除去可能的例外r=v2 3,都存在(3,2,1)-r-COLS(v).由于(3,2,1)-r-COLS(v)的存在性与(1,3,2)-r-COLS(v)的存在性是等价的,本文得到关于(1,3,2)-r-COLS(v)的同样结论.  相似文献   

13.
In this article, the author introduces the generalized difference paranormed sequence spaces c (△v^m, f, p, q, s), c0 (△v^m, f, p, q, s), and l∞ (△v^m, f, p, q, s) defined over a seminormed sequence space (X, q). The author also studies their properties like completeness, solidity, symmetricitv, etc.  相似文献   

14.
An L(d0,d2,...,dt)-labeling of a graph G is a function f from its vertex set V(G) to the set {0,1,..., k} for some positive integer k such that If(x) - f(y)l ≥di, if the distance between vertices x and y in G is equal to i for i = 1,2,...,t. The L(d1,d2,...,dt)-number λ(G;d1,d2,... ,dt) of G is the smallest integer number k such that G has an L(d1,d2,...,dr)- labeling with max{f (x)|x ∈ V(G)} = k. In this paper, we obtain the exact values for λ(Cn; 2, 2, 1) and λ(Cn; 3, 2, 1), and present lower and upper bounds for λ(Cn; 2,..., 2, 1,..., 1)  相似文献   

15.
In this paper, we present a discrete model to illustrate how two pieces of information interact with online social networks and investigate the dynamics of discrete-time information diffusion model in three types: reverse type, intervention type and mutualistic type. It is found that the model has orbits with period 2, 4, 6, 8, 12, 16, 20, 30, quasiperiodic orbit, and undergoes heteroclinic bifurcation near 1:2 point, a homoclinic structure near 1:3 resonance point and an invariant cycle bifurcated by period 4 orbit near 1:4 resonance point. Moreover, in order to regulate information diffusion process and information security, we give two control strategies, the hybrid control method and the feedback controller of polynomial functions, to control chaos, flip bifurcation, 1:2, 1:3 and 1:4 resonances, respectively, in the two-dimensional discrete system.  相似文献   

16.
关于K4同胚图色唯一性的几个新结果   总被引:4,自引:0,他引:4  
李为民 《应用数学》1991,4(3):43-47
本文证得:如果i,j,k,l,m,n中有四个数相等,而另外二个数不小于此数,则K_4(i,j,k,l,m,n)是色唯一的.此外,我们还得到了另外两族具有色唯一性的K_4同胚图.  相似文献   

17.
Lebesgue proved in 1940 that each 3-polytope with minimum degree 5 contains a 5-vertex for which the set of degrees of its neighbors is majorized by one of the following sequences(6, 6, 7, 7, 7), (6, 6, 6, 7, 9), (6, 6, 6, 6, 11)(5, 6, 7, 7, 8), (5, 6, 6, 7, 12), (5, 6, 6, 8, 10), (5, 6, 6, 6, 17)(5, 5, 7, 7, 13), (5, 5, 7, 8, 10), (5, 5, 6, 7, 27), (5, 5, 6, 6,∞), (5, 5, 6, 8, 15), (5, 5, 6, 9, 11)(5, 5, 5, 7, 41), (5, 5, 5, 8, 23), (5, 5, 5, 9, 17), (5, 5, 5, 10, 14), (5, 5, 5, 11, 13).We prove that each 3-polytope with minimum degree 5 without vertices of degree from 7 to 10 contains a 5-vertex whose set of degrees of its neighbors is majorized by one of the following sequences: (5, 6, 6, 5, ∞), (5, 6, 6, 6, 15), and (6, 6, 6, 6, 6), where all parameters are tight.  相似文献   

18.
互连网络的向量图模型   总被引:1,自引:0,他引:1  
n-超立方体,环网,k元n超立方体,Star网络,煎饼(pancake)网络,冒泡排序(bubble sort)网络,对换树的Cayley图,De Bruijn图,Kautz图,Consecutive-d有向图,循环图以及有向环图等已被广泛的应用做处理机或通信互连网络.这些网络的性能通常通过它们的度,直径,连通度,hamiltonian性,容错度以及路由选择算法等来度量.在本文中,首先,我们提出了有向向量图和向量图的概念;其次,我们开发了有向向量图模型和向量图模型来更好地设计,分析,改良互连网络;我们进一步证明了上述各类著名互连网络都可表示为有向向量图模型或向量图模型;更重要的是该模型能够使我们设计出了新的互连网络---双星网络和三角形网络.  相似文献   

19.
NANU Mathematical Institute, Kiev, Ukraine and MCS University, Lublin, Poland; NANU Mathematical Institute, Kiev, Ukraine and Bielefeld University, Germany. Translated from Funktsional'nyi Analiz i Ego Prilozheniya, Vol. 29, No. 3, pp. 51–55, July–September, 1995.  相似文献   

20.
基于对广义系统、泛导、泛对称、泛箱原理、泛系相对性提出了新的分析模式与新的相对数学化的简化强化的定义,发展了泛系方法论与泛系相对论的框架与理法,具体内容涉及:相对普适的数学化的泛系,200类对偶,对偶转化,泛对称转化,泛系辩证,八畴方法,泛系数学方法,广义量化,逼近转化原则,泛等价定理,供求分析,思维实验,广义灰色系统,等等.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号