Conditions for Homogeneity of Subpopulations

ＣｏｎｄｉｔｉｏｎｓｆｏｒＨｏｍｏｇｅｎｅｉｔｙｏｆＳｕｂｐｏｐｕｌａｔｉｏｎｓ＊）ＬｉＳｈｕｙｏｕ（李树有）（ＤｅｐａｒｔｍｅｎｔｏｆＢａｓｉｃＳｃｉｅｎｃｅ，ＬｉａｏｎｉｎｇＩｎｓｔｉｔｕｔｅｏｆＴｅｃｈｎｏｌｏｇｙ，Ｊｉｎｚｈｏｕ，Ｌｉａｏｎｉ...     

A Note for one of Inequality

In this paper, we find the largest contant C such that sin2 x xtanx > 2x2 cx5tan x 0相似文献   

Chaos for Subshifts of Finite Type

This paper deals with chaos for subshifts of finite type. We show that for any subshift of finite type determined by an irreducible and aperiodic matrix, there is a finitely chaotic set with full Hausdorff dimension. Moreover, for any subshift of finite type determined by a matrix, we point out that the cases including positive topological entropy, distributional chaos, chaos and Devaney chaos are mutually equivalent.     

Criteria of stability for a Class of Linear Systems

In this paper,employing the geometric criteria of stabilty we obtain some stable results of linear differential equations with impulsive effects.     

Bounds for Determinants of Quaternion Matrices

ＢｏｕｎｄｓｆｏｒＤｅｔｅｒｍｉｎａｎｔｓｏｆＱｕａｔｅｒｎｉｏｎＭａｔｒｉｃｅｓＨｕａｎｇＬｉｐｉｎｇ（黄礼平）（Ｄｅｐｔ．ｏｆＢａｓｉｃＳｃｉｅｎｃｅｓ，ＸｉａｎｇｔａｎＭｉｎｉｎｇＩｎｓｔｉｔｕｔｅ，Ｘｉａｎｇｔａｎ，４１１２０１）ＣａｉＹｏｎ...     

The Boundedness for Commutators of Multipliers

Let[b,T]be the commutator generated by a Lipschitz function b ∈ Lip(β)(0<β<1)and multiplierT.The authors studied the boundedness of[b,T]on the Lebesgue spaces and Hardy spaces.     

A new bound for an extension of Mason’s theorem for functions of several variables

In this paper, using the generalized Wronskian, we obtain a new sharp bound for the generalized Masons theorem [1] for functions of several variables. We also show that the Diophantine equation (The generalized Fermat-Catalan equation) where , such that k out of the n-polynomials are constant, and under certain conditions for has no non-constant solution. Received: 20 March 2003     

Propagation of singularities for solutions of Hamilton–Jacobi equations

We consider the viscosity solution of the Cauchy problem for a class of Hamilton–Jacobi equations and we show that the points of the C¹$C^1$ singular support of such a function propagate along the generalized characteristics for all the times.     

Lower Bounds for Dimensions of Sums of Sets

We study lower bounds for the Minkowski and Hausdorff dimensions of the algebraic sum E+K of two sets E,K⊂ℝ ^d .     

Analysis of a Linear Sampling Method for Identification of Obstacles

Some difficulties are pointed out in the methods for identification of obstacles based on the numerical verification of tile inclusion of a function in the range of an operator. Numerical examples are given to illustrate theoretical conclusions. Alternative methods of identification of obstacles are mentioned： the Support Function Method （SFM） and the Modified Rayleigh Conjecture （MRC） method.     

An Estimate of Inequality of Signature and Nullity for Links

ＡｎＥｓｔｉｍａｔｅｏｆＩｎｅｑｕａｌｉｔｙｏｆＳｉｇｎａｔｕｒｅａｎｄＮｕｌｌｉｔｙｆｏｒＬｉｎｋｓ￥ＬｉＱｉｓｈｅｎｇ（李起升）（Ｄｅｐｔ．ＯｆＭａｔｈ．ＨｅｎａｎＵｎｉｖｅｒｓｉｔｙ，Ｋａｉｆｅｎｇ４７５００１）Ａｂｓｔｒａｃｔ：Ａｎｉｎｅｑｕ...     

Dimension of divergence sets for dispersive equation

Consider the generalized dispersive equation defined by{iδtu+Ф(√-△)u=0,(x,t)∈R^n×R,u(x,0)=f(x),F∈F(R^n),(*)whereФ(√-△)is a pseudo-differential operator with symbolФ(|ζ|).In the present paper,assuming thatФsatisfies suitable growth conditions and the initial data in H^s(R^n),we bound the Hausdorff dimension of the sets on which the pointwise convergence of solutions to the dispersive equations(*)fails.These upper bounds of Hausdorff dimension shall be obtained via the Kolmogorov-Seliverstov-Plessner method.     

Normal Form for Families of Hamiltonian Systems

We consider perturbations of integrable Hamiltonian systems in the neighborhood of normally parabolic invariant tori. Using the techniques of KAM-theory we prove that there exists a canonical transformation that puts the Hamiltonian in normal form up to a remainder of weighted order 2d ＋ 1. And some dynamical consequences are obtained.     

Boundedness of Solutions for Elliptic Variational Inequalities

Ｂｏｕｎｄｅｄｎｅｓｓ　ｏｆ　Ｓｏｌｕｔｉｏｎｓ　ｆｏｒ　Ｅｌｌｉｐｔｉｃ　Ｖａｒｉａｔｉｏｎａｌ　ＩｎｅｑｕａｌｉｔｉｅｓＢｏｕｎｄｅｄｎｅｓｓｏｆＳｏｌｕｔｉｏｎｓｆｏｒＥｌｌｉｐｔｉｃＶａｒｉａｔｉｏｎａｌＩｎｅｑｕａｌｉｔｉｅｓ￥ＹｅＲｕｉｆ...     

Method of regularization for second-order stochastic ∗

The paper is concerned with the strong solution of secondorder stochastic evolution equations in a Hilbert space. We introduce the method of regularization to prove the existence, uniqueness of strong solution for such equations without the usual coercivity assumption. The result is applied to stochastic wave and plate equations to yield the existence of a unique strong solution for each of such problems arising from physical application.     

An analytic–numerical method for the construction of the reference law of operation for a class of mechanical controlled systems

An analytic–numerical method for the construction of a reference law of operation for a class of dynamic systems describing vibrations in controlled mechanical systems is proposed. By the reference law of operation of a system, we mean a law of the system motion that satisfies all the requirements for the quality and design features of the system under permanent external disturbances. As disturbances, we consider polyharmonic functions with known amplitudes and frequencies of the harmonics but unknown initial phases. For constructing the reference law of motion, an auxiliary optimal control problem is solved in which the cost function depends on a weighting coefficient. The choice of the weighting coefficient ensures the design of the reference law. Theoretical foundations of the proposed method are given.     

New Estimates for the Rate of Convergence of the Method of Subspace Corrections

We discuss estimates for the rate of convergence of the method of successive subspace corrections in terms of condition number estimate for the method of parallel subspace corrections. We provide upper bounds and in a special case, a lower bound for preconditioners defined via the method of successive subspace corrections.     

Examples of divergent fourier series for classes of functions of bounded Λ-variation

The author has shown earlier that the requirement that a continuous function belong to the class HBV ([?π, π] ^m ) for m ≥ 3 is not sufficient for the convergence of its Fourier series over rectangles. The author gave examples of functions of three and more variables from the Waterman class which are harmonic in the first variable and significantly narrower in the other variables and whose Fourier series are divergent at some point even on cubes. In the present paper, this assertion is strengthened. The main result is that such an example can be constructed even when the class with respect to the first variable is somewhat narrowed. Also the one-dimensional result due to Waterman is refined.     

Interpolation for a subclass of H ∞

We introduce and characterize two types of interpolating sequences in the unit disc \(\mathbb {D}\) of the complex plane for the class of all functions being the product of two analytic functions in \(\mathbb {D}\) , one bounded and another regular up to the boundary of \(\mathbb {D}\) , concretely in the Lipschitz class, and at least one of them vanishing at some point of \(\overline {\mathbb {D}}\) .