首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到10条相似文献,搜索用时 277 毫秒
1.
Let f be a holomorphic function on the unit polydisc Dn,with Taylor expansion f(z) = ∞ |k|=0 akzk ≡∞ (k1+···+kn=0) (ak1,···,kn zk1 1znkn)where k = (k1, , kn) ∈ Z+n. The authors define generalized Hilbert operator on Dn by Hγ,n(f)(z) = ∞ |k|=0 i1,···,in≥0 ai1,···,in n j=1 Γ(γj + kj + 1)Γ(kj + ij + 1) Γ(kj + 1)Γ(kj + ij + γj + 2) zk,where γ∈ Cn, such that R γj > -1, j = 1, 2, , n. An upper bound for the norm of the operator on Hardy spaces Hp(Dn) is found. The authors also present a Fejér-Riesz type inequalit...  相似文献   

2.
This paper is concerned with the following n-th ordinary differential equation:{u~(n)(t)=f(t,u(t),u~(1)(t),···,u~(n-1) (t)),for t∈(0,1),u~(i) (0)=0,0 ≤i≤n3,au~(n-2)(0)du~(n-1)(0)=0,cu~(n-2)(1)+du~(n-1)(1)=0,where a,c ∈ R,,≥,such that a~2 + b~2 0 and c~2+d~20,n ≥ 2,f:[0,1] × R → R is a continuous function.Assume that f satisfies one-sided Nagumo condition,the existence theorems of solutions of the boundary value problem for the n-th-order nonlinear differential equations above are established by using Leray-Schauder degree theory,lower and upper solutions,a priori estimate technique.  相似文献   

3.
《数学季刊》2016,(4):369-378
In this paper, we investigate the growth of solutions of the differential equations f(k)+Ak?1(z)f(k?1)+· · ·+A0(z)f =0, where Aj(z)(j=0, · · · , k?1) are entire functions. When there exists some coe?cient As(z)(s ∈ {1, · · · , k?1}) being a nonzero solution of f00+P(z)f =0, where P(z) is a polynomial with degree n(≥1) and A0(z) satisfiesσ(A0)≤1/2 or its Taylor expansion is Fabry gap, we obtain that every nonzero solution of such equations is of infinite order.  相似文献   

4.
邓铿 《应用数学》2005,18(2):181-187
我们研究初始值问题(e)u1/(e)t2=(e)2u1/(e)x2+‖u2(·,t)‖p, (e)2u2/(e)t2=(e)2u2/(e)x2+‖u1(·,t)‖q,-∞<x<∞,t>0,u1(x,0)=f1(x), (e)u1/(e)t(x,0)=g1(x),u2(x,0)=f2(x), (e)u2/(e)t(x,0)=g2(x),- ∞<x<∞,where‖ui(·,t)‖=∫∞-∞(4)i(x)|ui(x,t)|dx with (4)i(x)≥0 and ∫∞-∞(4)i(x)dx=1,i=1,2.然后建立解的全局存在和爆破的标准,提出爆破增长率.  相似文献   

5.
四层前向神经网络作为通用逼近器的一致性分析   总被引:2,自引:2,他引:0  
如果转移函数σ:R→R是Tauber-Wiener函数,即σ∈(TW), 本文给出了四层前向神经网络∑pi=1ui(q∑j=1uijσ(Aij·x+θij))作为通用逼近器的一致性分析,且选取了该网络具有某类特殊性质的连结权.例如,若f,g是连续函数,且f≤g,则相应的连结权关于f,g是递增的,等等.最后为验证结论,给出了一个模拟例子.  相似文献   

6.
戚文峰  朱宣勇 《数学学报》2001,44(3):445-452
设Ω是 Galois环 GR(2~d,r)的 Teichmuller代表集,则 GR(2~d,r)上每条序列a有唯一的权位分解, 其中a-i是Ω上序列,同时也可自然视为有限域F-(2~r),上序列.设f(x)是环 GR(2~d,r)上强本原多项式,G(f(x))表示 GR(2~d,r)上以f(x)为特征多项式的序列的全体,是F-(2~r)上一类d-1元多项式,  本文证明了压缩映射是单射,即对 a= b当且仅当对所有 a,b ∈ G(f(x)).  相似文献   

7.
Let G be a simple graph of order at least 2.A VE-total-coloring using k colors of a graph G is a mapping f from V (G) E(G) into {1,2,···,k} such that no edge receives the same color as one of its endpoints.Let C(u)={f(u)} {f(uv) | uv ∈ E(G)} be the color-set of u.If C(u)=C(v) for any two vertices u and v of V (G),then f is called a k-vertex-distinguishing VE-total coloring of G or a k-VDVET coloring of G for short.The minimum number of colors required for a VDVET coloring of G is denoted by χ ve vt (G) and it is called the VDVET chromatic number of G.In this paper we get cycle C n,path P n and complete graph K n of their VDVET chromatic numbers and propose a related conjecture.  相似文献   

8.
Let {X_n, n≥1} be a strictly stationary sequence of random variables, whichare either associated or negatively associated, f(·) be their common density. In this paper,the author shows a central limit theorem for a kernel estimate of f(·) under certain regularconditions.  相似文献   

9.
黄志刚 《数学杂志》2011,31(5):922-928
本文研究了由m个超越整函数函数f1,f2,···,fm生成的随机迭代系统的Fatou分支的有界性问题.利用复动力系统理论的方法,得到一个Fatou连通分支U分别作为游荡域和非游荡域有界的条件,推广了Zheng的结果,同时也是对Baker的问题在随机迭代系统情形的一个回答.  相似文献   

10.
The asymptotic distribution of the change-point estimator in a jump changepoint model is considered.For the jump change-point model Xi =a + θI{[nTo] < i ≤n} + εi,where εi (i =1,…,n) are independent ide...  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