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1.
本文主要研究如下的Briot-Bouquet微分从属P(Z)+ZP'(Z)/βP(Z)+γ<1+az/1+bz,p(0)=1其中p在|z|D<1内解析,β、γ、a、b为适当的实数,并由此解决了S.S.Miller和P.T.Mocanu提出的一。  相似文献   

2.
非退化扩散过程的极性的必要性   总被引:3,自引:1,他引:2  
设X(t)是一N维非退化扩散过程.设 E(0,∞)和 F RN都为紧集.本文给出了:P(X-1(F)∩E≠φ)>0,P(X-1(F)≠φ)>0和P(X(E)≠φ)>0的充分条件.证明了:i)设 N≥ 3,a)若 dim(F)<N-2,则 P(X-1(F)=φ)=1; b)若dim(F)>N-2,则 P(X-1(F)≠φ)>0; c)存在 F1 RN,F2 RN,dim(F1)=dim(F2)=N-2,但有P(X-1(F1)=φ)=1,P(X-1(F2)≠φ)>0.ii)设N=1,a)若dim(E)>1/2,则x∈R1,P(X-1(x)∩E≠φ)>0;b)存在E(0,∞),dim(E)=1/2,使得x∈R1,P(X-1(x)∩E≠φ)>0.以上这些结果,不仅仅是Brown运动的推广,即使就Brown运动的情形而言,其中有些结果也是新的.  相似文献   

3.
ABOUTNON-COOPERATIVEN-PERSONGAMES¥ZhangyadongandZhangshengkai(No1BaodingSt,InstituteofO-R.116001.DalianChINA)Abstract:Inthepa...  相似文献   

4.
第Ⅰ卷(参考公式,略)1.选择题(1)如图,I是全集,M、P、S是I的3个子集,则阴影部分所表示的集合是(  ). (A)(M∩P)∩S (B)(M∩P)∪S (C)(M∩P)∩S   (D)(M∩P)∪S(2)已知映射f:A→B,其中,集合A={-3,-2,-1,1,2,3,4},集合B中的元素都是A中元素在映射f下的象,且对任意的a∈A,在B中和它对应的元素是|a|,则集合B中元素的个数是(  ). (A)6  (B)5  (C)4  (D)7(3)若函数y=f(x)的反函数是y=g(x),…  相似文献   

5.
设X为一个n元集合,Cnk为X的所有k元子集全体,若A∈A,B∈B有|A∩B|≥t,则称(A,B)为一个交叉t-相交子集族.本文得到最大交叉t-相交子集族和最大非空交叉2-相交子集族.证明如下两个结论.(1)若(A,B)为一个交叉t-相交子集族,且a≤b及a+b≤n+t-1,则|A+B|≤max{(bn),(an)},且当(A;B)=(φ,Cnb)或(Cna,φ)时达到上界.(2)若(A,B)为一个交叉2-相交子集族,且a<b,a+b≤n-1及(n,a,b)≠(2i,i-1,i)(i为任意正整数),又A,B均非空,则|A+B|≤1+(bn)-(b(n-a))-a((b-1)(n-a))且当(A,B)=({A},Cnb-{B||B|=b,|A∩B|≤1})时达到上界.  相似文献   

6.
ψ_α函数和Brogyden族   总被引:1,自引:0,他引:1  
彭积明  袁亚湘 《计算数学》1994,16(2):204-210
ψ_α函数和Brogyden族彭积明,袁亚湘(中国科学院计算中心)ψ_α-FUNCTIONANDBROYDEN'SFAMILY¥PengJi-ming;YuanYa-xiang(ComputingCenter,AcademiaSinica)Abstra...  相似文献   

7.
VACUUMPROBLEMFORTHEDAMPEDp-SYSTEMZhengYongshu(郑永树)(Dept.ofAppl.Math.,HuaqiaoUniuersity,Quanzhou,362011,China.)Abstract:Theaut...  相似文献   

8.
AbsoluteContinuityfortheOcupationTimesofSupper-BrownianMotioninaSuper-BrownianMediumHongWenming(洪文明)(Dept.ofMath.,BeijingNorm...  相似文献   

9.
LOCALANDGLOBALEXPOSEDPOINTSM.Beltagy(MathematicsDepartment,FacultyofScienceTantaUniversity,Egypt.)Abstract:Inthispaperwederiv...  相似文献   

10.
DECOMPOSITIONFORBERS-ORLICZSPACESZhaoRuhan(赵如汉)(WuhanIust.ofMath.Sci.,AcadrmiaSinda.,Wuhan430071,China.)DECOMPOSITIONFORBERS-...  相似文献   

11.
We prove the following theorems. Theorem A. Let G be a group of order 160 satisfying one of the following conditions. (1) G has an image isomorphic to D20 × Z2 (for example, if GD20 × K). (2) G has a normal 5‐Sylow subgroup and an elementary abelian 2‐Sylow subgroup. (3) G has an abelian image of exponent 2, 4, 5, or 10 and order greater than 20. Then G cannot contain a (160, 54, 18) difference set. Theorem B. Suppose G is a nonabelian group with 2‐Sylow subgroup S and 5‐Sylow subgroup T and contains a (160, 54, 18) difference set. Then we have one of three possibilities. (1) T is normal, |ϕ(S)| = 8, and one of the following is true: (a) G = S × T and S is nonabelian; (b) G has a D10 image; or (c) G has a Frobenius image of order 20. (2) G has a Frobenius image of order 80. (3) G is of index 6 in A Γ L(1, 16). To prove the first case of Theorem A, we find the possible distribution of a putative difference set with the stipulated parameters among the cosets of a normal subgroup using irreducible representations of the quotient; we show that no such distribution is possible. The other two cases are due to others. In the second (due to Pott) irreducible representations of the elementary abelian quotient of order 32 give a contradiction. In the third (due to an anonymous referee), the contradiction derives from a theorem of Lander together with Dillon's “dihedral trick.” Theorem B summarizes the open nonabelian cases based on this work. © 2000 John Wiley & Sons, Inc. J Combin Designs 8: 221–231, 2000  相似文献   

12.
This paper studies the relations between T.I. conditions and cyclic conditions on the Sylow p-subgroups of a finite group G. As examples, the following two results are proved., 1.Let G be a finite group with a T. I. Sylow p-subgroup P. If p=3 or 5, we suppose G contains no composition factors isomorphic to the simple group L_{2}(2^{3}) or S(2^{5}) respectively, If G has a normal subgroup W such that p|(|W|,|G/W|), then G is p-solvable. 2.Let G be a finite group with a T.I. Sylow p-subgroup P. Suppose p>ll and P is not normal in G. Then P is cyclic if and only if G has no composition factors L_{2}(p^{n})(n>1) and U_{s}(p^{m})(m\geq 1).  相似文献   

13.
有限群的最大子群的性质对群结构的影响   总被引:1,自引:0,他引:1  
有限群G的一个子群称为在G中是π-拟正规的若它与G的每一个Sylow-子群是交换的.G的一个子群H称为在G中是c-可补的若存在G的子群N使得G=HN且H∩N≤HG=CoreG(H).本文证明了:设F是一个包含超可解群系u的饱和群系,G有一个正规子群H使得G/H∈F.则G∈F若下列之一成立:(1)H的每个Sylow子群的所有极大子群在G中或者是π-拟正规的或者是c-可补的;(2)F*(H)的每个Sylow子群的所有极大子群在G中或者是π-拟正规的或者是c-可补的,其中F*(H)是H的广义Fitting子群.此结论统一了一些最近的结果.  相似文献   

14.
In Theorem 1, letting p be a prime, we prove: (1) If G=Sn is a symmetric group of degree n, then G contains two Sylow p-subgroups with trivial intersection iff (p, n) ∉ {(3, 3), (2, 2), (2, 4), (2, 8)}, and (2) If H=An is an alternating group of degree n, then H contains two Sylow p-subgroups with trivial intersection iff (p, n) ∉ {(3, 3), (2, 4)}. In Theorem 2, we argue that if G is a finite simple non-Abelian group and p is a prime, then G contains a pair of Sylow p-subgroups with trivial intersection. Also we present the corollary which says that if P is a Sylow subgroup of a finite simple non-Abelian group G, then ‖G‖>‖P‖2. Supported by RFFR grants Nos. 93-01-01529, 93-01-01501, and 96-01-01893, and by International Science Foundation and Government of Russia grant RPC300. Translated fromAlgebra i Logika, Vol. 35, No. 4, pp. 424–432, July–August, 1996.  相似文献   

15.
设G是有限群,p是|G|的一个素因子,P是G的一个Sylow p-子群.若下列条件之一满足,则G是p-幂零:(1)P的极大子群均在G中S-半正规且(|G|,p-1)=1;(2)P的二次极大子群均在G中S-半正规且(|G|,p2-1)=1.  相似文献   

16.
夏道行 《数学学报》1956,6(4):598-618
<正> 1.設G是z平面上的兩連區域,它的每一個境界部分都不止含有一點.我們知道有唯一的半徑R使圓環1<|ζ|相似文献   

17.
刘醴泉 《数学学报》1957,7(2):313-326
<正> 设函数 f(z)=z+a_2Z~2+…在单位圆|z|<1上是正则的单叶的.这种函数的全体形成一族 S.S 中满足条件|f(z)|1上是单叶的,除开极点ζ=∞是正则的.这种函数的全体形成一族∑.∑中满足条件|F(ζ)|>R的函  相似文献   

18.
耿济 《数学学报》1959,9(2):174-180
<正> 本文是前文的续作,这里引用的記号与以前是一致的,例如(?)为实或复阵(?)的特征根,A~* 是 A 的共轭转置阵,(?)此外,还引用一些新的记号,(?)  相似文献   

19.
Let \Omega be a field, and let F denote the Frobenius matrix: $[F = \left( {\begin{array}{*{20}{c}} 0&{ - {\alpha _n}}\{{E_{n - 1}}}&\alpha \end{array}} \right)\]$ where \alpha is an n-1 dimentional vector over Q, and E_n- 1 is identity matrix over \Omega. Theorem 1. There hold two elementary decompositions of Frobenius matrix: (i) F=SJB, where S, J are two symmetric matrices, and B is an involutory matrix; (ii) F=CQD, where O is an involutory matrix, Q is an orthogonal matrix over \Omega, and D is a diagonal matrix. We use the decomposition (i) to deduce the following two theorems: Theorem 2. Every square matrix over \Omega is a product of twe symmetric matrices and one involutory matrix. Theorem 3. Every square matrix over \Omega is a product of not more than four symmetric matrices. By using the decomposition (ii), we easily verify the following Theorem 4(Wonenburger-Djokovic') . The necessary and sufficient condition that a square matrix A may be decomposed as a product of two involutory matrices is that A is nonsingular and similar to its inverse A^-1 over Q (See [2, 3]). We also use the decomosition (ii) to obtain Theorem 5. Every unimodular matrix is similar to the matrix CQB, where C, B are two involutory matrices, and Q is an orthogonal matrix over Q. As a consequence of Theorem 5. we deduce immediately the following Theorem 6 (Gustafson-Halmos-Radjavi). Every unimodular matrix may be decomposed as a product of not more than four involutory matrices (See [1] ). Finally, we use the decomposition (ii) to derive the following Thoerem 7. If the unimodular matrix A possesses one invariant factor which is not constant polynomial, or the determinant of the unimodular matrix A is I and A possesses two invariant factors with the same degree (>0), then A may be decomposed as a product of three involutory matrices. All of the proofs of the above theorems are constructive.  相似文献   

20.
A finite group G is called a generalized PST-group if every subgroup contained in F(G) permutes all Sylow subgroups of G, where F(G) is the Fitting subgroup of G. The class of generalized PST-groups is not subgroup and quotient group closed, and it properly contains the class of PST-groups. In this paper, the structure of generalized PST-groups is first investigated. Then, with its help, groups whose every subgroup (or every quotient group) is a generalized PST-group are deter- mined, and it is shown that such groups are precisely PST-groups. As applications, T-groups and PT-groups are characterized.  相似文献   

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