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971.
在任意的Banach空间的条件下,具误差的Ishikawa迭代程序强收敛到非线性方程x+Tx=f的唯一解并且是几乎稳定的.其结果推广、改进和统一了Zeng和Liu的相关结果. 相似文献
972.
杨理平 《数学物理学报(A辑)》2009,29(1):186-192
在适当的条件下,证明了有限族严格伪压缩映象具误差的隐迭代序列强收敛于其公共不动点. 所得结果改进了Osilike 与 Xu, Ori 的相应结果. 相似文献
973.
对于无限级随机Dirichlet级数几乎每一条水平线都是无限级无例外小函数的强Borel线. 相似文献
974.
Gong-Bo Wang · Yun-He Meng · Wei Zheng · Guo-Jian Tang College of Aerospace Material Engineering National University of Defense Technology Changsha China 《Acta Mechanica Sinica》2011,27(5):809-816
Sun synchronous orbit and frozen orbit formed due to J 2 perturbation have very strict constraints on orbital parameters,which have restricted the application a lot.In this paper,several control strategies were illustrated to realize Sun synchronous frozen orbit with arbitrary orbital elements using continuous low-thrust.Firstly,according to mean element method,the averaged rate of change of the orbital elements,originating from disturbing constant accelerations over one orbital period,was derived from Gauss’ variation of parameters equations.Then,we proposed that binormal acceleration could be used to realize Sun synchronous orbit,and radial or transverse acceleration could be adopted to eliminate the rotation of the argument of the perigee.Finally,amending methods on the control strategies mentioned above were presented to eliminate the residual secular growth.Simulation results showed that the control strategies illustrated in this paper could realize Sun synchronous frozen orbit with arbitrary orbital elements,and can save much more energy than the schemes presented in previous studies,and have no side effect on other orbital parameters’ secular motion. 相似文献
975.
Let G be the set of finite graphs whose vertices belong to some fixed countable set, and let ≡ be an equivalence relation on G. By the strengthening of ≡ we mean an equivalence relation ≡s such that G≡sH, where G,H∈G, if for every F∈G, G∪F≡H∪F. The most important case that we study in this paper concerns equivalence relations defined by graph properties. We write G≡ΦH, where Φ is a graph property and G,H∈G, if either both G and H have the property Φ, or both do not have it. We characterize the strengthening of the relations ≡Φ for several graph properties Φ. For example, if Φ is the property of being a k-connected graph, we find a polynomially verifiable (for k fixed) condition that characterizes the pairs of graphs equivalent with respect to . We obtain similar results when Φ is the property of being k-colorable, edge 2-colorable, Hamiltonian, or planar, and when Φ is the property of containing a subgraph isomorphic to a fixed graph H. We also prove several general theorems that provide conditions for ≡s to be of some specific form. For example, we find a necessary and sufficient condition for the relation ≡s to be the identity. Finally, we make a few observations on the strengthening in a more general case when G is the set of finite subsets of some countable set. 相似文献
976.
Pigong Han 《Journal of Differential Equations》2011,250(10):3937-3959
In a half space, we consider the asymptotic behavior of the strong solution for the non-stationary Navier-Stokes equations. In particular, the decay rates of the second order derivatives of the Navier-Stokes flows in (n?2) with 1?r?∞ are derived by using Lq−Lr estimates and a clever analysis on the fractional powers of the Stokes operator. In addition, we prove that the strong solution and its first and second derivatives decay in time more rapidly than observed in general if the initial datum lies in a suitable weighted space. 相似文献
977.
Maria Bernadette Donato 《Journal of Functional Analysis》2011,261(8):2083-2093
In this paper an infinite dimensional generalized Lagrange multipliers rule for convex optimization problems is presented and necessary and sufficient optimality conditions are given in order to guarantee the strong duality. Furthermore, an application is presented, in particular the existence of Lagrange multipliers associated to the bi-obstacle problem is obtained. 相似文献
978.
Sergiu Aizicovici 《Journal of Mathematical Analysis and Applications》2011,375(1):342-364
We consider a nonlinear periodic problem, driven by the scalar p-Laplacian with a concave term and a Caratheodory perturbation. We assume that this perturbation f(t,x) is (p−1)-linear at ±∞, and resonance can occur with respect to an eigenvalue λm+1, m?2, of the negative periodic scalar p-Laplacian. Using a combination of variational techniques, based on the critical point theory, with Morse theory, we establish the existence of at least three nontrivial solutions. Useful in our considerations is an alternative minimax characterization of λ1>0 (the first nonzero eigenvalue) that we prove in this work. 相似文献
979.
Kosuke Ono 《Journal of Mathematical Analysis and Applications》2011,381(1):229-239
We consider the initial-boundary value problem for the degenerate strongly damped wave equations of Kirchhoff type: . For all t?0, we will give the optimal decay estimate C−1(1+t)−1/γ?‖A1/2u(t)‖2?C(1+t)−1/γ, when either the coefficient ρ is appropriately small or the initial data are appropriately small. And, we will show a decay property of the norm ‖Au(t)‖2 for t?0. 相似文献
980.
Hyungjin Huh 《Journal of Mathematical Analysis and Applications》2011,381(2):513-520
We obtain a strong solution in charge critical space L2(R) of the Thirring system and Federbusch equations in one space dimension by using solution representation of the models. The uniqueness is obtained for the solution Ψ∈L∞([0,T];L2(R)∩L4(R)). A decay of local charge and asymptotic behavior of the field can be shown directly. 相似文献