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41.
Yujia Wang Tong Wang Xuebo Yang Jiae Yang 《International Journal of Adaptive Control and Signal Processing》2021,35(7):1388-1403
In this article, a decentralized optimal tracking control strategy is proposed for a class of nonlinear systems with tracking error constraints by utilizing adaptive dynamic programming (ADP). It should be noted that ADP technology cannot be directly used to solve decentralized optimal tracking problem of large-scale interconnected nonlinear system with nonzero equilibrium points, since that an infinite domain performance index function may result in an unsolvable solution. In addition, by introducing a smooth function, the constrained tracking error is transformed into an unconstrained one. Then, the error dynamics and a new infinite domain performance index function are designed, such that ADP technology can be used. Following the designed performance index function, the tracking error can be ensured within a small neighborhood of zero. Finally, the feasibility and the effectiveness of the proposed decentralized optimal control scheme are verified through two simulation examples. 相似文献
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Majid Mazouchi Mohammad Bagher Naghibi‐Sistani Seyed Kamal Hosseini Sani Farzaneh Tatari Hamidreza Modares 《International Journal of Adaptive Control and Signal Processing》2019,33(2):262-284
This paper develops a relative output‐feedback–based solution to the containment control of linear heterogeneous multiagent systems. A distributed optimal control protocol is presented for the followers to not only assure that their outputs fall into the convex hull of the leaders' output but also optimizes their transient performance. The proposed optimal solution is composed of a feedback part, depending of the followers' state, and a feed‐forward part, depending on the convex hull of the leaders' state. To comply with most real‐world applications, the feedback and feed‐forward states are assumed to be unavailable and are estimated using two distributed observers. That is, a distributed observer is designed to measure each agent's states using only its relative output measurements and the information that it receives by its neighbors. Another adaptive distributed observer is designed, which uses exchange of information between followers over a communication network to estimate the convex hull of the leaders' state. The proposed observer relaxes the restrictive requirement of having access to the complete knowledge of the leaders' dynamics by all the followers. An off‐policy reinforcement learning algorithm on an actor‐critic structure is next developed to solve the optimal containment control problem online, using relative output measurements and without requiring the leaders' dynamics. Finally, the theoretical results are verified by numerical simulations. 相似文献
43.
以鄂北水资源配置工程为对象,研究大型调水工程背景下的多水源多目标优化配置。将鄂北地区水库分为充蓄水库、补偿水库与在线水库等3类,根据各类水库特点对鄂北水资源配置工程进行系统概化,建立以年缺水量最小和调水成本最低为目标函数的多水源多目标优化配置模型。采用权重系数法进行求解得到非劣解集。最后采用基于区间犹豫模糊语言与TOPSIS的多目标决策方法对各方案的缺水量与调水量作出评价并遴选出最优方案。研究结果表明:对鄂北水资源配置工程而言,缺水量与调水量的权重比为7∶3的方案综合评价最优,重视缺水的同时兼顾调水成本;基于区间犹豫模糊语言集与TOPSIS的水资源多目标决策方法经本文实例验证具有较高的稳定性与可行性。 相似文献
44.
直接法合成的苯基氯硅烷粗单体是一种成分复杂的多组分混合物,其分离纯化较为困难,国内外鲜有报道。文中设计了4种分离方案并与文献中已有的分离方法进行对比。利用Aspen Plus对以上5种分离方案进行严格模拟计算,旨在保证一苯基三氯硅烷、二苯基二氯硅烷的纯度及收率的前提下找出年度费用最低的分离方案。基于易分离度系数法的分离方案年度总费用最低,比现有分离方案的年度总费用降低了7.8%。以该流程为初始方案,利用调优法找出4组相邻分离方案。通过对4组分离方案进行精确模拟计算,得到结论:调优方案3年度总费用最低,为苯基氯硅烷单体分离的最优分离方案,比初始方案年度总费用低了3.5%。 相似文献
45.
An approach to mechanistic event recognition applied on monitoring organic matter depletion in SBRs 下载免费PDF全文
Mariano N. Cruz Bournazou Stefan Junne Peter Neubauer Tilman Barz Harvey Arellano‐Garcia Costas Kravaris 《American Institute of Chemical Engineers》2014,60(10):3460-3472
A fundamental practice in process engineering is monitoring the state dynamics of a system. Unfortunately, observability of some states is related to high costs, time, and efforts. The mechanistic event recognition (MER) aims to detect an event (defined as a change of the system with specific significance to the operation of the process) that cannot be directly observed but has some predictable effect on the dynamics of the systems. MER attempts to apply fault diagnosis techniques using mechanistic “recognition” models to describe the process. A systematic method for building recognition models using optimal experimental design tools is presented. As proof of concept, the MER approach to detect organic matter depletion in sequencing batch reactors, measuring only ammonia, dissolved oxygen, and nitroxides is applied. The event, that is, consumption of organic matter to a level below 50 gCOD/m3, was successfully detected even though microbial activity is known to continue after organic matter depletion. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3460–3472, 2014 相似文献
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污泥负荷( Ns)是指单位质量的活性污泥在单位时间内所去除的有机污染物的量,单位kgCOD/( kgMLSS·d)。利用泰州市紫光水业污水处理厂初沉池出水和曝气池的活性污泥制作一定浓度的污泥混合液,并在0.1~0.3 kgCOD/( kgMLSS·d)污泥负荷中选择5个实验点,改变停留时间进行好氧生化反应,分别测COD, TP, NH3-N, TN的去除率,讨论不同污泥负荷不同停留时间对污水处理效果的影响,综合考虑污泥沉降性能和去除污水COD和脱氮除磷的效果,确定最佳污泥负荷为0.20 kgCOD/( kgMLSS·d)。 相似文献
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氯化石蜡生产中因液氯质量问题引起反应终止,分析了影响液氯质量的因素(主要是液氯中硫酸、二氧化硫、铁的化合物、水分、光气及二氧化氯等含量超标),提出了解决措施. 相似文献