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991.
992.
We provide two approaches to the numerical analysis of stochastic control problems. The analyses rely on linear programming formulations of the control problem and allow numerical comparison between controls and numerical verification of optimality. The formulations characterize the processes through the moments of the induced occupation measures. We deal directly with the processes rather than with some approximation to the processes. Excellent software is readily available, since the computations involve finite-dimensional linear programs. 相似文献
993.
Abstract We have already reported the results of direct observations of electron-topological phase transition (ETT) in cadmium'. The appearance of new dHvA-frequencies corresponding to the Fermi surface (FS) change, i.e. restoring of folding of hole “monster” and electron “needle” appearance is observed under pressure. In t h i s report we are going to enlarge on the ETT consequences study in cadmium-on the advent of anomalous electronic features in transverse magnetoresistance and thermoelectric power. 相似文献
994.
An opinion dynamics model for a Command and Control (C2) organization is essential for simulating combat system effectiveness. However, few studies have addressed opinion evolution in C2 simulation. With the goal of overcoming this research gap, this paper proposes an opinion exchange model, which is illustrated through a practical example of an Armored Division network. The model is divided into homogeneous and heterogeneous aspects: the former is mainly characterized by communication rules and types, while the latter is extended with the influence of multi-level opinion leaders. After carrying out the simulation of the two main models, the results show that the opinion evolution of the hierarchical leveled C2 organization with descending influence is much more complex and unpredictable than that of social networks. 相似文献
995.
假设股票的价格遵循CEV过程,经济因子满足两个相互独立的布朗运动,运用风险敏感性随机最优控制理论得到新的结论,最后对于简化的模型,得到最优长期增长率的解析解. 相似文献
996.
Sul Lee Sunho Jeong Dongjo Kim Sookhyun Hwang Minhyon Jeon Jooho Moon 《Superlattices and Microstructures》2008
Nanocrystalline zinc oxide (ZnO) particles with controlled shapes and sizes were prepared at 180 °C by a simple polyol method. The amount of water and the method of addition played an important role in determining the characteristics of the synthesized particles. Rod-shaped ZnO particles with major axis lengths of ∼114 nm were obtained by heating the precursor solution, while equiaxial particles with average diameters of ∼24 nm were prepared by injecting water into hot precursor solution. Increasing the amount of water added to the precursor solution enlarged the aspect ratio of the rod-shaped particles and increased the particle size of the equiaxial particles due to enhanced hydrolysis and condensation of the Zn ion complex. 相似文献
997.
分散化供应链的自组织演化机制建模与仿真 总被引:1,自引:0,他引:1
供应链是一个复杂适应系统.提出了分散化供应链演化的自组织机制.在开放结构下,多企业主体为了适应外部环境,在非线性互动中涌现出供应链协作结构和协调模式.借鉴生物系统环境适应能力思想,建立了分散化供应链自组织演化模型,并采用Multi-agent技术进行仿真,证明了分散化供应链的自组织演化机制.外部环境和企业内部机制因素控制着分散化供应链的演化,其演化对初始条件高度敏感,存在着锁定、路径依赖和混沌等自组织系统特性. 相似文献
998.
We study and give the definition of the exact Lagrangian controllability of the viscous Burgers equation and prove a local result. We give similar results for the heat equation in dimension 1. 相似文献
999.
R. Filliger M.-O. Hongler L. Streit 《Journal of Optimization Theory and Applications》2008,137(3):497-505
We present an exactly soluble optimal stochastic control problem involving a diffusive two-states random evolution process and connect it to a nonlinear reaction-diffusion type of equation by using the technique of logarithmic transformations. The work generalizes the recently established connection between the non-linear Boltzmann-like equations introduced by Ruijgrok and Wu and the optimal control of a two-states random evolution process. In the sense of this generalization, the nonlinear reaction-diffusion equation is identified as the natural diffusive generalization of the Ruijgrok–Wu and Boltzmann model. 相似文献
1000.