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991.
In this paper we use the Hicks property for a variational problem on a graph. For an elastic system defined on a graph we state a well-posed problem which implies the definition and the study of the influence function. 相似文献
992.
993.
G. Z. Chelidze 《Mathematical Notes》2000,68(2):263-269
To study intersections of embedded bounded closed sets in Banach space, a numerical parameter was introduced earlier; in a
certain sense, this parameter describes the deviation of the shape of a set from that of a sphere. Critical values of this
parameter for some classes of Banach spaces are determined, a new numerical parameter serving the same purpose is introduced,
and the relation between the two parameters is examined.
Translated fromMatematicheskie Zametki, Vol. 68, No. 2, pp. 303–310, August, 2000. 相似文献
994.
Jacek Polewczak 《Journal of statistical physics》2000,100(1-2):327-362
Existence of global-in-time, spatially inhomogeneous, and L
1-renormalized solutions is proven for the model of simple reacting spheres under the assumptions that initially the system has a finite total mass, energy, and entropy. 相似文献
995.
Banach空间中微分方程解的存在与唯一性 总被引:6,自引:0,他引:6
在一般Banach空间中,作者讨论了微分方程的初值问题u=f(t,u),u(0)=x0.在比文[6]中弱Carathodory条件更弱的情况下,不仅放宽了[6]中的一个重要不等式条件,还去掉了另一与之相关的不等式限制,仍获得了初值问题解的存在与唯一性及解的迭代逼近.对周期边值问题也获得了类似结果. 相似文献
996.
Dario Pierotti 《Journal of Differential Equations》2008,244(9):2350-2371
We consider the problem of the steady flow of an ideal heavy fluid around a submerged beam. The problem is obtained from the free-boundary problem of the flow past a submerged obstacle in the limit of bodies of vanishing thickness. We introduce a special Sobolev space formulation of the problem in term of a perturbed stream function and prove its unique solvability for every value of the unperturbed flow velocity, with the possible exception of a discrete set depending on the geometry of the domain. The asymptotic properties of the solutions are discussed. 相似文献
997.
An active set subspace Barzilai-Borwein gradient algorithm for large-scale bound constrained optimization is proposed. The
active sets are estimated by an identification technique. The search direction consists of two parts: some of the components
are simply defined; the other components are determined by the Barzilai-Borwein gradient method. In this work, a nonmonotone
line search strategy that guarantees global convergence is used. Preliminary numerical results show that the proposed method
is promising, and competitive with the well-known method SPG on a subset of bound constrained problems from CUTEr collection.
This work was supported by the 973 project granted 2004CB719402 and the NSF project of China granted 10471036. 相似文献
998.
Fuyi Li Yanbiao Zhang Yuhua Li 《Journal of Mathematical Analysis and Applications》2008,344(1):417-428
In this paper, we consider the fourth-order Neumann boundary value problem u(4)(t)−2u″(t)+u(t)=f(t,u(t)) for all t∈[0,1] and subject to u′(0)=u′(1)=u?(0)=u?(1)=0. Using the fixed point index and the critical group, we establish the existence theorem of solutions that guarantees the problem has at least one positive solution and two sign-changing solutions under certain conditions. 相似文献
999.
Classical and modified Lagrangian bounds for the optimal value of optimization problems with a double decomposable structure are examined. For the class of generalized assignment problems, this property of constraints is used to design a Benders algorithm for solving the modified dual problem. Numerical results are presented that compare the quality of classical and modified bounds. 相似文献
1000.
Przemys?aw Górka 《Journal of Mathematical Analysis and Applications》2008,341(2):1413-1426
We examine the evolution of crystals in three dimensions. We assume that the Wulff shape is a prism with a hexagonal base. We include the Gibbs-Thomson law on the crystal surface and the so-called Stefan condition. We show local in time existence of solutions assuming that the initial crystal has admissible shape. 相似文献