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1.
This article presents a new approach for solving the Optimal Control Problem (OCP) of linear time-delay systems with a quadratic cost functional. The proposed method can also be used for designing optimal control time-delay systems with disturbance. In this study, the Variational Iteration Method (VIM) is employed to convert the original Time-Delay Optimal Control Problem (TDOCP) into a sequence of nonhomogeneous linear two-point boundary value problems (TPBVPs). The optimal control law obtained consists of an accurate linear feedback term and a nonlinear compensation term which is the limit of an adjoint vector sequence. The feedback term is determined by solving Riccati matrix differential equation. By using the finite-step iteration of a nonlinear compensation sequence, we can obtain a suboptimal control law. Finally, Illustrative examples are included to demonstrate the validity and applicability of the technique. 相似文献
2.
使用液力偶合器因故障频繁,对高炉稳产、高产造成严重威胁,而且维修费用较高,对偶合器改造后,应用金属迭片挠性联轴器其故障率、维修费用都很低。 相似文献
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4.
本文提出了求解非线性问题的一种新方法——逐次迭代法,本方法先是给出一个初始近似解,然后将这个近似解进行校正迭代,使之接近于真实解,把一个非线性问题转化为一个线性问题来解决。 相似文献
5.
With the growing size and complexity of power systems, system analysis—such as transients calculation—takes much time. Hence, fast calculation methods are required. Although parallel processing is a hopeful method, there have been difficulties in the parallel solution of linear equations which appear in power-flow calculations by the Newton-Raphson method. This paper aims at the fast calculation of the power-flow problem by means of parallel processing. In order to improve the suitability to the parallel solution of the differential equation in transients calculation, we assume the use of a direct-mapping parallel processing machine to map directly the network of a power system onto a network of processors. Under this assumption, we propose a new parallel-processing-oriented method in which the linear equation is solved by linear iterations between nodes with Aitken acceleration. We simulate the method on three model power systems and compare this Parallel Iterative Method (PIN) with a Parallel Direct Method (PDM) which uses the banded matrix according to the number of operations required. As a result, we can expect that PIM may solve linear equations faster than PDM with m processors, although the PIM might be inferior to the PDM with m × m processors, where m denotes the half-band width of the banded matrix. 相似文献
6.
提出了一种全局优化的多面体匹配方法,该方法对物体的拓扑关系和结构关系进行多级匹配,利用全局优化的松驰迭代方法减少匹配误差,并由匹配的一致性准则进行匹配结果的检测,根据物体的内在特征来进行匹配,从而解决非同构物体的匹配.可广泛应用于物体识别、三维物体重建、医学图象处理等领域,实验证明此方法质量好、自动化程度高,是一种有效的全局优化结构匹配方法. 相似文献
7.
介绍了集团变分法的集团概率变量、配置熵等统计分析的理论基础及Helmholtz自由能的描述模型.提出了巨势及相对化学势的几何分析理论.讨论了应用集团变分法和巨势分析理论进行相平衡计算的过程,并分析了同结构平衡相图计算的若干实例. 相似文献
8.
The design of an adaptive nonlinear controller for the control of a fluidized bed reactor is derived by using exact linearization techniques. Reset action and parameter adaptation are used to make more robust the precise compensation of nonlinear terms, which is called for in the linearization technique. A nonlinear antiwindup mechanism is introduced to handle reset windup problem and to provide fast response without large overshoot. Simulation results show that the proposed adaptive controller guarantees good setpoint tracking. The developed estimation algorithm allows accurate estimation of the parameters for which the regressor component is not zero. 相似文献
9.
Xi-Ren CaoAuthor Vitae Zhiyuan RenAuthor Vitae Shalabh BhatnagarAuthor Vitae Michael FuAuthor Vitae Steven MarcusAuthor Vitae 《Automatica》2002,38(6):929-943
We propose a time aggregation approach for the solution of infinite horizon average cost Markov decision processes via policy iteration. In this approach, policy update is only carried out when the process visits a subset of the state space. As in state aggregation, this approach leads to a reduced state space, which may lead to a substantial reduction in computational and storage requirements, especially for problems with certain structural properties. However, in contrast to state aggregation, which generally results in an approximate model due to the loss of Markov property, time aggregation suffers no loss of accuracy, because the Markov property is preserved. Single sample path-based estimation algorithms are developed that allow the time aggregation approach to be implemented on-line for practical systems. Some numerical and simulation examples are presented to illustrate the ideas and potential computational savings. 相似文献
10.
波束形成和解码的联合迭代接收技术 总被引:1,自引:1,他引:0
SDMA技术是提高频谱利用率的有效技术,但在判决反馈最小均方波束形成中,在深衰落之后期望用户波束会指向干扰用户,严重影响了波束形成的性能。文中提出在波束形成和信道解码之后,经过编码、交织,重新生成波束形成的参考信号,再进行波束形成,有效克服了深衰落之后的波束指向错误。计算机仿真结果证明了该方法的有效性。 相似文献