分析了当前的非线性模型预测控制（Nonlinear Model Predictive Control,NMPC）技术和应用现状,并为今后的研究和发展提出了一些课题。给出了NMPC的主要原理,并概述了NMPC的关键优点/不足及其一些理论、计算和实施方面的问题。除了关于N...分析了当前的非线性模型预测控制（Nonlinear Model Predictive Control,NMPC）技术和应用现状,并为今后的研究和发展提出了一些课题。给出了NMPC的主要原理,并概述了NMPC的关键优点/不足及其一些理论、计算和实施方面的问题。除了关于NMPC的数学构造及其闭环稳定性的基本问题的一般描述,还对如NMPC的鲁棒构造问题、输出反馈问题,并对闭环系统的性能预测进行了讨论。一个NMPC算法的成功取决于最初选择的非线性模型结构的合理性,所以给出了可为一个新的NMPC算法形成潜在数学构造的一些合适的非线性模型结构的简述。总之,3个对NMPC应用的最主要障碍是：非线性模型的开发;状态估计;快速、可靠的实时控制算法的求解方案。对于未来NMPC技术的需求包括非线性模型辨识的系统方法发展;非线性估计方法;可靠的数值求解技术;以及评价NMPC应用的更好方法。展开更多
On the basis of composition duality principles, augmented three-field macrohybrid mixed variational problems and finite element schemes are analyzed. The compatibility condition adopted here, for compositional dualiza...On the basis of composition duality principles, augmented three-field macrohybrid mixed variational problems and finite element schemes are analyzed. The compatibility condition adopted here, for compositional dualization, is the coupling operator surjectivity, property that expresses in a general operator sense the Ladysenskaja-Babulka-Brezzi inf-sup condition. Variational macro-hybridization is performed under the assumption of decomposable primal and dual spaces relative to nonoverlapping domain decompositions. Then, through compositional dualization macro-hybrid mixed problems are obtained, with internal boundary dual traces as Lagrange multipliers. Also, ＂mass＂ preconditioned aug- mentation of three-field formulations are derived, stabilizing macro-hybrid mixed finite element schemes and rendering possible speed up of rates of convergence. Dual mixed incompressible Darcy flow problems illustrate the theory throughout the paper.展开更多
This paper derives the Lindell formula based on the generalized variational principle.For the complex dielectric constant measurement of a small lossy dielectric rod with Rayleigh-Ritz method, an accurate variational ...This paper derives the Lindell formula based on the generalized variational principle.For the complex dielectric constant measurement of a small lossy dielectric rod with Rayleigh-Ritz method, an accurate variational analysis is given. The concept of complex frequency isintroduced in general, and the stability of the solution is discussed. Comparing with the resultof perturbation method, it is concluded that the deviation of perturbation algorithm should betaken into consideration.展开更多
文摘分析了当前的非线性模型预测控制（Nonlinear Model Predictive Control,NMPC）技术和应用现状,并为今后的研究和发展提出了一些课题。给出了NMPC的主要原理,并概述了NMPC的关键优点/不足及其一些理论、计算和实施方面的问题。除了关于NMPC的数学构造及其闭环稳定性的基本问题的一般描述,还对如NMPC的鲁棒构造问题、输出反馈问题,并对闭环系统的性能预测进行了讨论。一个NMPC算法的成功取决于最初选择的非线性模型结构的合理性,所以给出了可为一个新的NMPC算法形成潜在数学构造的一些合适的非线性模型结构的简述。总之,3个对NMPC应用的最主要障碍是：非线性模型的开发;状态估计;快速、可靠的实时控制算法的求解方案。对于未来NMPC技术的需求包括非线性模型辨识的系统方法发展;非线性估计方法;可靠的数值求解技术;以及评价NMPC应用的更好方法。
文摘On the basis of composition duality principles, augmented three-field macrohybrid mixed variational problems and finite element schemes are analyzed. The compatibility condition adopted here, for compositional dualization, is the coupling operator surjectivity, property that expresses in a general operator sense the Ladysenskaja-Babulka-Brezzi inf-sup condition. Variational macro-hybridization is performed under the assumption of decomposable primal and dual spaces relative to nonoverlapping domain decompositions. Then, through compositional dualization macro-hybrid mixed problems are obtained, with internal boundary dual traces as Lagrange multipliers. Also, ＂mass＂ preconditioned aug- mentation of three-field formulations are derived, stabilizing macro-hybrid mixed finite element schemes and rendering possible speed up of rates of convergence. Dual mixed incompressible Darcy flow problems illustrate the theory throughout the paper.
文摘This paper derives the Lindell formula based on the generalized variational principle.For the complex dielectric constant measurement of a small lossy dielectric rod with Rayleigh-Ritz method, an accurate variational analysis is given. The concept of complex frequency isintroduced in general, and the stability of the solution is discussed. Comparing with the resultof perturbation method, it is concluded that the deviation of perturbation algorithm should betaken into consideration.
