算子方程AX-XA=C的可解性

本文在一般Ｂａｎａｃｈ空间研究带无界算子Ａ的算子方程ＡＸ－ＸＡ＝Ｃ的可解性,利用单参数积分双半群方法,通过在算子代数Ｌ（Ｅ）上考虑间断问题弱解,证明了当算子Ａ在Ｌ（Ｅ）上诱导的算子Ａ是弱积分双半群的母元时,只要Ｃ满足一定条件,上述算子方程可解．     

线性算子双半群及在间断和脉冲微分方程中的应用(英)

研究抽象Ｂａｎａｃｈ空间中线性微微分方程的可解性,利用算子双半群方法,讨论了在确定时间跳跃或脉冲的线性微分方程解的存在性,表明在一定条件下间断或脉冲方程的解存在唯一．     

T（t）-积分半群

本文引入T(t)-积分半群的概念，它是n次积分半群及a次积分半群的推广．我们给出T(t)-积分半群的定义、生成定理，并讨论相应的一类积分型抽象Cauchy问题解的存在唯一性．     

T(t)积分半群

本文引入Ｔ（ｔ）积分半群的概念，它是ｎ次积分半群［１］及α次积分半群［２］的推广．我们给出Ｔ（ｔ）积分半群的定义、生成定理，并讨论相应的一类积分型抽象Ｃａｕｃｈｙ问题解的存在唯一性．     

Banach空间抽象线性脉冲方程的可解范围

本文在一船Ｂａｎａｃｈ空间Ｘ上研究抽象线性脉冲方程的可解范围，其中Ａ是闭线性算子，文中构造了Ｘ的一个线性子空间Ｖ且在Ｖ上定义范数成为Ｂａｎａｃｈ空间，Ａ限制在Ｖ上生成指数衰减的强连续双半群，从而表明方程在Ｖ上可解，并证明Ｖ是方程可解的极大范围。     

强连续双半群与积分双半群

本文研究积分双半群与有界线性算子双半群的关系,证明了Ｂａｎａｃｈ空间Ｘ上的指数有界积分双半群可以作为Ｘ的某个子空间上具有较强范数拓扑下的有界线性算了强连续双半 积分双半群也可作为较大空间上俱有较弱范数拓扑下的有界线性算子强连续双半群积分的限制,上述结果可以用来解释抽象边值问题的弱解的意义。     

一类Schrodinger方程的周期解和谱方法

本文利用半群理论讨论了一类非线性非自共轭Ｓｃｈｒｏｄｉｎｇｅｒ方程周期初边值解的存在唯一性，以及它的Ｆｏｕｒｉｅｒ谱方法的可解性，稳定性和收敛性     

二阶线性发展方程初值问题的某些推广

本文用压缩半群理论讨论了二阶线性发展方程组的初值问题;还用解析半群讨论了一类变系数的二阶线性发展方程的初值问题,使这一类初值问题的可解性与含t的算子的一阶线性发展方程解的理论统一起来,这是数学力学中的一类重要方程。     

线性算子双半群的扰动定理

本文研究有界线性算子强连续双半群的扰动问题。文中首先研究与强连续双半群母元有关的算子方程的可解性与算子的相似性。在此基础上证明了在一定条件下可化为指数衰减的强连续双半群经适当扰动后仍是一个可化为指数衰减的强连续双半群。     

反应扩散方程古典解的最大吸引子

利用能量积分和解析半群的有关估计，一类反应扩散方程非负古典解在连续函数空间的最大吸引子的存在性被证明，且非线性项取为任意阶多项式．     

SOME PROPERTIES OF INTEGRATED BISEMIGROUPS

1 IntroductionRecently tl1e collcept of integrated bisen1group is developed fOr solving the abstract dy-nantic equatioll in [1]. This is an extellsioll of theory of bisemigroup8I2--4t1o-l5] alld integratedsentigroups[5-9]. In tl1e present paper, we will discuss the properties of integrated bisen1igroups.First we recall sollle basic properties of integrated bisentigroups, including the definition andthe infillitesimal generator of illtegrated bisemigroups. In Section 3, we discuss the structu…     

INTEGRATED BISEMIGROUP AND APPLICATIONS TO IMPULSIVE DIFFERENTIALEQUATIONS

1IntroductionRecellt1yauth0rintr0ducethec0nceptofintegratedbisemigroupwhichliavebeendeveloped~,.lorsoivmgtheabstractkineticequation[11'Thisthe0ryextendstheoperatorsbisendgroupthe0r}toabstractboundaryvaluepr0blmewith0peratorwhichd0notgenerateastrong1ycontiuousbisentigroup.Ontheotherhand,thistheoryextendsthetheoryofintegratedsedrigr0upals0.ItismorericherthantheintegratedseAngroup8[5-91.InthispaPerwewillusethistlieoryt0studythes0lvabilityofabstractimpul8ivcdifferentialequati0ns.Insection2.werec…     

Banach空间积分双半群的生成条件

研究Banach空间中积分双半群的生成条件.利用算子A的豫解算子,给出了积分双半群T(t)的生成定理.结果表明:如果对任意的x∈X,f∈X*,以及A|λ]<δ,λ∈ρ(A),有∈Lp(R),则存在算子族S(t),t∈R,S(t)强连续且满足积分双半群的定义.     

On perturbations of abstract fractional differential equations by nonlinear operators

We prove the unique solvability of a Cauchy-type problem for an abstract parabolic equation containing fractional derivatives and a nonlinear perturbation term. The result is applied to establish the solvability of the inverse coefficient problem for a fractional-order equation.     

Spectral analysis and correct solvability of abstract integrodifferential equations arising in thermophysics and acoustics

In the present paper, we study integrodifferential equations with unbounded operator coefficients in Hilbert spaces. The principal part of the equation is an abstract hyperbolic equation perturbed by summands with Volterra integral operators. These equations represent an abstract form of the Gurtin–Pipkin integrodifferential equation describing the process of heat conduction in media with memory and the process of sound conduction in viscoelastic media and arise in averaging problems in perforated media (the Darcy law). The correct solvability of initial-boundary problems for the specified equations is established in weighted Sobolev spaces on a positive semiaxis. Spectral problems for operator-functions are analyzed. Such functions are symbols of these equations. The spectrum of the abstract integrodifferential Gurtin–Pipkin equation is investigated.     

Well-defined solvability and spectral analysis of abstract hyperbolic integrodifferential equations

The authors study integrodifferential equations in Hilbert space. The coefficients of the equations are unbounded and the principal part is an abstract hyperbolic equation perturbed by terms with Volterra integral operators. Such equations can be regarded as an abstract generalization of the Gurtin–Pipkin integrodifferential equation that describes heat transfer in materials with memory and has a number of other applications. Well-defined solvability of initial boundary value problems for such equations is established in weighted Sobolev spaces on the positive semi-axis. The authors examine spectral problems for operator-valued functions representing the symbols of the said equations and study the spectrum of the abstract Gurtin–Pipkin integrodifferential equation.