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991.
In this paper, we develop second-order necessary and sufficient optimality conditions for multiobjective optimization problems with both equality and inequality constraints. First, we generalize the Lin fundamental theorem (Ref. 1) to second-order tangent sets; then, based on the above generalized theorem, we derive second-order necessary and sufficient conditions for efficiency. 相似文献
992.
Tatiana Korona Bogumil Jeziorski Robert Moszynski Geerd H. F. Diercksen 《Theoretical chemistry accounts》1999,101(4):282-291
Symmetry-adapted perturbation theory is extended to the (quasi) degenerate, open-shell case. The new formalism is tested
in calculations of the interaction energies for a helium atom in the ground state interacting with an excited hydrogen atom.
It is shown that the method gives satisfactory results if the coupling with higher Rydberg states of the dimer is small, as
is the case for the A2Σ+,B2Π,E2Π,32Π, and 12Δ states of HeH. For the C2Σ+ state convergence of the method is very slow, but it can be improved by including the n=3 states in the model space.
Received: 3 June 1998 / Accepted: 9 September 1998 / Published online: 7 December 1998 相似文献
993.
本文利用摄动的思想,以摄动有理曲线(曲面)的系数的无穷模作为优化目标,给出了用多项式曲线(曲面)逼近有理曲线(曲面)的一种新方法.同以前的各种方法相比,该方法不仅收敛而且具有更快的收敛速度,并且可以与细分技术相结合,得到有理曲线与曲面的整体光滑、分片多项式的逼近. 相似文献
994.
HAI Wenhua 《理论物理通讯》1999,31(2):297-300
Abstract High-ordered correction of wavefunction for Schrodinger equation with one dimensional potential V(x) and interaction Hamiltonian H′(x) has been found by introducing a new particular solution φEk(0) for H′(z) = 0. Convergence conditions of the rvavefunction lead to the formulas of energy corrections and scattering amplitudes. It is shown that the result can avoid some divergence difficulties of quantum mechanics. 相似文献
995.
Solitons of the sine-Gordon system interacting with a disturbed external field are handled by using a direct method. Theoretical analysis reveals that the single soliton perturbed by a periodic field leads to chaotic behavior of the system, and the perturbed double soliton is unstable for most of physically interesting spacetime disturbances. 相似文献
996.
We investigate the single-impurity Anderson model by means of the recently introduced modified perturbation theory. This approximation scheme yields reasonable results away from the symmetric case. The agreement with exactly known results for the symmetric case is checked, and results for the non-symmetric case are presented. With decreasing conduction band occupation, the breakdown of the screening of the local moment is observed. In the crossover regime between Kondo limit and mixed-valence regime, an enhanced zero-temperature susceptibility is found. 相似文献
997.
Giampiero Esposito 《Foundations of Physics Letters》2000,13(1):29-40
A modification of the spiked harmonic oscillator is studied in the case for which the perturbation potential contains both an inverse power and a linear term. It is then possible to evaluate trial functions by solving an integral equation due to the occurrence of the linear term. The general form of such integral equation is obtained by using a Green-function method, and adding a modified Bessel function of second kind which solves an homogeneous problem with Dirichlet boundary condition at the origin. 相似文献
998.
The soliton perturbations of the modified Korteweg de Vries equation corresponding to different signs of the nonlinear term are studied. The first-order effects of perturbation on a soliton, namely, both the slow time-dependence of the soliton parameters and first-order corrections are derived in a direct approach based on the separation of variables. 相似文献
999.
基于运动约束解过约束并联机构变形协调方程 总被引:2,自引:0,他引:2
提出利用运动约束关系来间接求解过约束并联机构变形协调方程.首先介绍了该方法的原理,接着分别针对平面和空间过约束并联机构,详述该方法的解决步骤,结果验证了该方法的正确性,从中还可看出该方法在求解复杂过约束并联机构时非常简洁,最后介绍了采用该方法解决多度过约束问题. 相似文献
1000.