一类高阶线性微分方程解的增长性

本文研究了在Aj(z),aj(j=0,1,…,k-1)满足一些条件下方程f(k)+Ak-1(z)eak-1f(k-1)+…+A0(z)ea0zf=0解的超级和在Aj(z),Pj(j)(j=0,1,…,k-1)满足一些条件下方程f(k)+Ak-1(z)ePk-1(z)f(k-1)+…+Aj(z)eajzf(j)+…+A0(z)eP0(z)f=0解的级。     

关于高阶线性微分方程解的增长性

在本文中,我们研究了一类高阶齐次线性微分方程f(k) +Ak-1f(k-1)+…+Aof=0,其中Aj(z) (j=0,1,…,k-1)是有限级整函数,且存在As(z)(s∈{0,1,…,k-1))是超越的且σ(As)＜1/2或其泰勒展式为缺项级数.我们给出了方程任一解f(≠)0的增长估计.     

一类高阶整函数系数微分方程解的增长级、下级与超级

该文研究了一类高阶整函数系数微分方程解的增长性,对方程f~(k)+A_(k-1)(z)e~(ak-1z).f~(k-1)+…+A_0(z)e~(a0z)f=0与方程f~(k)+(A_(k-1)(z)e~(ak-1z)+D_(k-1)(z))f~(k-1)+…+(A_0(z)e~(a0z)+D_0(z))f=0中a_j(0≤j≤k-1)幅角主值不全相等的情形,得到了解的增长级、下级与超级的精确估计.     

高阶复微分方程关于迭代级的辐角分布

设Aj是整函数(j=0,1,…,k-2),其中i(A0)=p,i(Aj)＜p,或σp(Aj)＜σp(A0)(j=1,2,…,k-2),0＜p＜+∞.本文研究微分方程f(k)+Ak-2f(k-2)+…+A0f=0(k≥2)解的辐角分布并得出零点聚值线和Borel方向之间的关系.所得结论推广了先前的结果.     

一类非齐次复微分方程解的增长性

研究了一类线性非齐次微分方程f(k)+ak-1f(k-1)+…+a1f-′(eQ(z)-a0)f=eQ(z)+F(z)解的增长性,其中aj(j=0,1,…,k-1)为常数,Q(z)为非常数多项式,F(z)为级小于deg Q的整函数.     

高阶复微分方程解的超级的角域分布

设f1,f2,…,fn是复方程f(n)+An-1f(n-1)+…+A0f=0的n个线性无关解,其中A0,A1,…,An-1是不全为多项式,且至少有一个为无限级整函数,σ2(Aj)=0(j=1,2,…,n-1).假设E=f1,f2,…,fn.研究了微分方f(n)+An-1f(n-1)+…+A0f=0的解在角域中的零点分布,获得E的超级为+∞的Borel方向与零点聚值线的关系.     

限制零点个数的亚纯函数的正规定则

设k,n(≥k+1)是两个正整数,a(≠0),b是两个有穷复数,F为区域D内的一族亚纯函数.如果对于任意的f∈F,f的零点重级大于等于k+1,并且在D内满足f+a[L(f)]~n-b至多有n-k-1个判别的零点,那么F在D内正规·这里L(f)=f~((k))(z)+a_1f~((k-1))(z)+…+a_(k-1)f'(z)+a_kf(z),其中a_1(z),a_2(z),…,a_k(z)是区域D上的全纯函数.     

一类高阶复微分方程解的增长性

本文研究高阶线性微分方程f~((k))+A_(k-1)f~((k-1))+···+A1f′+A0f=0解的增长性,其中Aj(j=0,···,k-1)为整函数.当存在某个系数A_s是方程ω′′+P(z)ω=0的一个非零解时,我们得到上述方程具有无穷级解的判定条件,并对解的超级进行了估计.这里的P(z)为非零多项式,当P(z)为特定形式的多项式时,A_s可取为Airy函数,Weber-Hermite函数或指数函数.     

On the Growth of Solutions of a Class of Higher Order Linear Differential Equations

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.     

高阶亚纯函数系数微分方程的解及其导数的不动点

研究了高阶线性微分方程f~(k)+A_(k-1)(z)f~(k-1)+…+A_1(z)f′+A_0(z)f=0的非零解f,及其一阶、二阶导数,f~(i)(i=1,2)的不动点性质,这里A_j(z)(j=0,1,…k-1)为亚纯函数,得到了若δ(∞,A_0)>0,且满足max{i(A1),i(A2),…,i(A_(k-1))}相似文献   

Characterization of types of asymptotic discernibility of families of hypotheses

We give a characterization of the types of asymptotic discernibility of families of hypotheses in the case of hypothetical measures that are not, in general, mutually absolutely continuous. The case when the logarithm of the likelihood ratio admits an asymptotic expansion of the type of an expansion with local asymptotic normality is examined in detail. Examples are studied.Translated fromTeoriya Sluchainykh Protsessov, Vol. 15, pp. 64–71, 1987.     

Study of the blow-up of solutions of systems of equations of hydrodynamic type

Mathematical Notes - We study the initial boundary-value problem for three-dimensional systems of equations of pseudoparabolic type. The system is similar to the Oskolkov system, but differs from...     

Singularities of Solutions of One Class of Equations of Continuum Mechanics

We analyze one class of families of integral equations and describe the dependence of the singularities of solutions of integral equations on the dimensions of the families of kernels of equations. On the basis of these results, we propose procedures for the construction of approximate solutions for a small parameter.     

Determination of asymptotic solutions of problems of nonlinear theories of thermoviscoelasticity

It is shown that the asymptotic solution of a problem of the nonlinear theory of thermoviscoelasticity, if it exists, can be found directly from the solution of the asymptotic boundary-value problem without completely solving the starting problem.M. V. Lomonosov Moscow State University. Translated from Mekhanika Polimerov, No. 3, pp. 395–400, May–June, 1976.     

Emptiness of set of points of lower semicontinuity of Lyapunov exponents

We consider parametric families of differential systems with coefficients that are bounded and continuous on the half-line and uniformly in time continuously depend on a real parameter. For each Lyapunov exponent, we construct a family such that the Lyapunov exponent of its systems treated as a function of the parameter is not a lower semicontinuous function for any value of the parameter.     

图表示范畴的两个子范畴

引进图表示范畴的两个子范畴,研究它们的同调性质。     

Distribution of types of symmetry of tensors of high degree

The asymptotic distribution of tensors of degree N in symmetry types is studied in this paper.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 155, pp. 181–186, 1986.     

Properties of operators of extension and contraction of ideals of algebras of invariants of reductive groups in positive characteristic

V. I. Lenin Tashkent State University. Translated from Funktsional'nyi Analiz i Ego Prilozheniya, Vol. 25, No. 4, pp. 53–61, October–December, 1991.