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941.
A new method is introduced for solving equality constrained nonlinear optimization problems. This method does not use a penalty
function, nor a filter, and yet can be proved to be globally convergent to first-order stationary points. It uses different
trust-regions to cope with the nonlinearities of the objective function and the constraints, and allows inexact SQP steps
that do not lie exactly in the nullspace of the local Jacobian. Preliminary numerical experiments on CUTEr problems indicate that the method performs well.
相似文献
942.
Jussi Laitila 《Mathematische Nachrichten》2010,283(11):1646-1653
943.
Xiuyun Zheng 《Applied mathematics and computation》2010,216(12):3778-3785
In this paper, we propose a new projection method for the solution of variational inequality problems. The method is simple, which uses only function evaluations and projections onto the feasible set. We adopt a new step-size rule and a new search direction in the new method. Under the mild conditions, we prove the proposed method is globally convergent. Preliminary numerical results are reported. 相似文献
944.
The paper describes and compares the performance of two options for numerically representing the surface tension force in combination with the level set interface‐tracking method. In both models, the surface tension is represented as a body force, concentrated near the interface, but the technical implementation is different: the first model is based on a traditional level set approach in which the force is distributed in a band around the interface using a regularized delta function, whereas in the second, the force is partly distributed in a band around the interface and partly localized to the actual computational cells containing the interface. A comparative study, involving analysis of several two‐phase flows with moving interfaces, shows that in general the two surface tension models produce results of similar accuracy. However, in the particular case of merging and pinching‐off of interfaces, the traditional level set model of surface tension produces an error that results in non‐converging solutions for film‐like interfaces (i.e. ones involving large contact areas). In contrast, the second model, based on the localized representation of the surface tension force, displays consistent first‐order convergence. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
945.
We prove the equivalence of the three different definitions of the viscosity solution for the integro-differential equation with the Lévy operator. The two of the definitions are known in the preceding works of the author and the others, and the last one is new. A construction of a sequence of the approximating test functions to the subsolution (or the supersolution) is indispensable for the proof, and it is done explicitly in the paper. 相似文献
946.
We describe the spectrum of the Laplacian for a homogeneous graph acted on by a discrete group. This follows from a more general result which describes the spectrum of a convolution operator on a homogeneous space of a locally compact group. We also prove a version of Harnack inequality for a Schrödinger operator on an invariant homogeneous graph. 相似文献
947.
Sergey A. Denisov 《Journal of Functional Analysis》2008,254(8):2186-2226
For a large class of Schrödinger operators, we introduce the hyperbolic quadratic pencils by making the coupling constant dependent on the energy in the very special way. For these pencils, many problems of scattering theory are significantly easier to study. Then, we give some applications to the original Schrödinger operators including one-dimensional Schrödinger operators with L2-operator-valued potentials, multidimensional Schrödinger operators with slowly decaying potentials. 相似文献
948.
949.
Neal Bez 《Journal of Functional Analysis》2008,255(12):3281-3302
For all d?2 and p∈(1,max(2,(d+1)/2)], we prove sharp Lp to Lp(Lq) estimates (modulo an endpoint) for a directional maximal operator associated to curves generated by the dilation matrices exp((logt)P), where P has real entries and eigenvalues with positive real part. For the corresponding Hilbert transform we prove an analogous result for all d?2 and p∈(1,2]. As corollaries, we prove Lp bounds for variable kernel singular integral operators and Nikodym-type maximal operators taking averages over certain families of curved sets in Rd. 相似文献
950.
Jingbo Xia 《Journal of Functional Analysis》2008,255(1):25-45
We consider Hankel operators on the Hardy space of the unit sphere in Cn. We show that a large amount of information about the function f−Pf can be recovered from the Hankel operator Hf. For example, if Hf is compact, then the function f−Pf is necessarily in VMO. 相似文献