Boundedness of global positive solutions of a porous medium equation with a moving localized source

In this paper a porous medium equation with a moving localized source ut=ur(Δu+af(u(x₀(t),t))) is considered. It is shown that under certain conditions solutions of the above equation blow up in finite time for large a or large initial data while there exist global positive solutions to the above equation for small a or small initial data. Moreover, in one space dimension case, it is also shown that all global positive solutions of the above equation are uniformly bounded, and this differs from that of a porous medium equation with a local source.     

Edelstein's method and fixed point theorems for some generalized nonexpansive mappings

A new condition for mappings, called condition (C), which is more general than nonexpansiveness, was recently introduced by Suzuki [T. Suzuki, Fixed point theorems and convergence theorems for some generalized nonexpansive mappings, J. Math. Anal. Appl. 340 (2008) 1088-1095]. Following the idea of Kirk and Massa Theorem in [W.A. Kirk, S. Massa, Remarks on asymptotic and Chebyshev centers, Houston J. Math. 16 (1990) 364-375], we prove a fixed point theorem for mappings with condition (C) on a Banach space such that its asymptotic center in a bounded closed and convex subset of each bounded sequence is nonempty and compact. This covers a result obtained by Suzuki [T. Suzuki, Fixed point theorems and convergence theorems for some generalized nonexpansive mappings, J. Math. Anal. Appl. 340 (2008) 1088-1095]. We also present fixed point theorems for this class of mappings defined on weakly compact convex subsets of Banach spaces satisfying property (D). Consequently, we extend the results in [T. Suzuki, Fixed point theorems and convergence theorems for some generalized nonexpansive mappings, J. Math. Anal. Appl. 340 (2008) 1088-1095] to many other Banach spaces.     

Growth order and stability of semigroups and cosine operator functions

Equivalent conditions for a trajectory of a C₀-semigroup T(⋅) (resp. cosine function C(⋅)) of operators to have the growth order O(tα) or o(tα) are expressed in terms of Cesàro and Abel means of the norm of the trajectory. We then deduce characterizations of growth order and stability for T(⋅) and C(⋅). It is also shown that under some Tauberian condition the uniform boundedness (resp. strong convergence) of T(⋅) is equivalent to the uniform boundedness (resp. strong convergence) of its Abel means.     

A hyperchaotic system from a chaotic system with one saddle and two stable node-foci

This paper presents a 4D new hyperchaotic system which is constructed by a linear controller to a 3D new chaotic system with one saddle and two stable node-foci. Some complex dynamical behaviors such as ultimate boundedness, chaos and hyperchaos of the simple 4D autonomous system are investigated and analyzed. The corresponding bounded hyperchaotic and chaotic attractor is first numerically verified through investigating phase trajectories, Lyapunove exponents, bifurcation path, analysis of power spectrum and Poincaré projections. Finally, two complete mathematical characterizations for 4D Hopf bifurcation are rigorous derived and studied.     

Invariant curves and boundedness of solutions of a class of reversible systems

In this paper, the boundedness of all solutions for the following planar reversible system Ju ′ = ?H (u) + G (u) + h (t) (1) is discussed, where the function H (u) ∈ C²(?², ?⁺) is positive for u ≠ 0 and positively (q, p)‐quasihomogeneous of quasi‐degree pq, G ∈ C⁵ is bounded, h ∈ C⁶ is 2π ‐periodic and J is the standard symplectic matrix. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

单位球上$\mu$-Bloch空间之间的广义Ces\`{a}ro算子

Let μ, v ∈ [0, 1） be normal functions and g be holomorphic function on the unit ball. In this paper, we prove that the generalized Cesaro operator Tg ：βμ→βv is bounded and compact.     

实Clifford分析中双正则函数列的性质

在给出了实Clifford分析中双正则函数列内闭一致有界和内闭一致连续的定义的基础上,讨论了内闭一致有界双正则函数列的内闭一致连续性、完备性、列紧性和收敛性.     

三阶非线性微分方程解的渐近性

建立了三阶非线性微分方程…x+φ(x,x.,¨x)¨x+f(x,x.)=p(t,x,x.,¨x)的一切解有界和收敛到零的充分条件.     

含k-次增生算子方程（1–k）x＋Tx=f解的Ishikawa迭代逼近

在一致光滑的实Banach空间中,研究当T为k-次增生算子时,非线性方程（1-k）x＋Tx=f具混合误差的Ishikawa迭代解,给出了强收敛定理,并对Ishikawa迭代程序关于含k-次增生算子方程（1-k）x＋Tx=f的稳定性进行了讨论,推广和改进了近期一些文献的相关结果.     

COMPOSITION TYPE OPERATORS FROM HARDY SPACES TO μ-BLOCH SPACES ON THE UNIT BALL

Let φ be a holomorphic self-map of Bn and ψ ∈ H（Hn）. A composition type operator is defined by Tψ,φ（f） = ψf o φ for f ∈ H（Bn）, which is a generalization of the multiplication operator and the composition operator. In this article, the necessary and sufficient conditions are given for the composition type operator Tψ,φ to be bounded or compact from Hardy space HP（Bn） to μ-Bloch space Bμ（Bn）. The conditions are some supremums concerned with ψ,φ, their derivatives and Bergman metric of Bn. At the same time, two corollaries are obtained.