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61.
《Advanced Engineering Informatics》2015,29(1):87-100
The original prototype of the cellular automaton (CA) shading system (CASS) for building facades was based on rectangular array of cells and used liquid crystal technology. This paper introduces polarized film shading system (PFSS) – an alternative approach based on opto-mechanical modules whose opacity is a function of the rotation of polarized film elements. PFSS in regular tessellations: triangular, square and hexagonal are discussed. Simulations for each type of tessellation are presented and visualized. Visual attractiveness of emergent CA patterns manifested by “particles” and “solitons” is discussed. 相似文献
62.
Heuristic Dynamic Programming Using Echo State Network For Multivariable Tracking Control Of Wastewater Treatment Process 下载免费PDF全文
This paper proposes a heuristic dynamic programming (HDP) scheme to simultaneously control the dissolved oxygen concentration and the nitrate level in wastewater treatment processes (WWTP). Unlike traditional HDP schemes, the optimal control values are calculated in an analytical way by the proposed HDP controller. It can reduce the learning burden of the HDP controller to a great extent. The system model and the evaluation index J are approximated by two echo state networks (ESNs). Gradient‐based learning algorithms are employed to train both ESNs online, and the convergence of the training algorithm is investigated based on Lyapunov theory. The performance of the proposed ESN‐based HDP (E‐HDP) controller is tested and evaluated on a WWTP benchmark. Experimental results demonstrate that the proposed approach can achieve effective performance. 相似文献
63.
Robust‐Adaptive Control Strategies for a Time Delay Bioelectrochemical Process Using Interval Observers 下载免费PDF全文
The paper addresses the design and the analysis of adaptive and robust‐adaptive control strategies for a complex recycled wastewater treatment bioprocess. The design procedures are developed under the realistic assumptions that the bacterial growth rates are unknown and the influent flow rates are time‐varying and uncertain, but some lower and upper bounds of these uncertainties are known. The proposed control structures are achieved by combining a linearizing control law with an appropriately (asymptotic or interval based) state observer and with a parameter estimator used for on‐line estimation of unknown kinetics. These approaches are applied to a complex time delay bioprocess resulting from the association of a recycling bioreactor with an electrochemical reactor. Numerical simulations are performed in order to validate the proposed algorithms. 相似文献
64.
In this paper, a novel robust observer-based adaptive controller is presented using a proposed simplified type-2 fuzzy neural network (ST2FNN) and a new three dimensional type-2 membership function is presented. Proposed controller can be applied to the control of high-order nonlinear systems and adaptation of the consequent parameters and stability analysis are carried out using Lyapunov theorem. Moreover, a new adaptive compensator is presented to eliminate the effect of the external disturbance, unknown nonlinear functions approximation errors and sate estimation errors. In the proposed scheme, using the Lyapunov and Barbalat's theorem it is shown that the system is stable and the tracking error of the system converges to zero asymptotically. The proposed method is simulated on a flexible joint robot, two-link robot manipulator and inverted double pendulums system. Simulation results confirm that in contrast to other robust techniques, our proposed method is simple, give better performance in the presence of noise, external disturbance and uncertainties, and has less computational cost. 相似文献
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66.
This paper deals with the development of effective techniques to automatically obtain the optimum management of petroleum fields aiming to increase the oil production during a given concession period of exploration. The optimization formulations of such a problem turn out to be highly multimodal, and may involve constraints. In this paper, we develop a robust particle swarm algorithm coupled with a novel adaptive constraint-handling technique to search for the global optimum of these formulations. However, this is a population-based method, which therefore requires a high number of evaluations of an objective function. Since the performance evaluation of a given management scheme requires a computationally expensive high-fidelity simulation, it is not practicable to use it directly to guide the search. In order to overcome this drawback, a Kriging surrogate model is used, which is trained offline via evaluations of a High-Fidelity simulator on a number of sample points. The optimizer then seeks the optimum of the surrogate model. 相似文献
67.
非结构化数据通常指相对于关系数据而言没有固定的显式结构的数据,比如视频、音频、图像、文档等非结构化数据。根据权威数据咨询机构或研究机构的预测报告显示,近 5~10年的数据量将呈指数级增长,而其中的非结构化数据占到当前数字信息总量的70%~85%。面对如此庞大的数据量和信息量,如何有效管理非结构化数据、获得有价值的信息或知识显得迫在眉睫。(非结构化) 数据管理可以简单化为3个目标,即:实现数据的“存得下、管得了、用的上”。本文将主要围绕前两个基本目标介绍目前的非结构化数据存储管理的研究情况。同时介绍中国人民大学非结构数据管理(Unstructured DataManagement,UDM)研究小组基于“自由表”数据模型和BUD(Bank of Unstructured Data)参考体系模型在这一个问题上所作的初步研究与探索工作,以及在原型平台myBUD中的若干存储管理技术。 相似文献
68.
Adaptive detection of range-spread targets without secondary data is addressed in a multichannel autoregressive Gaussian disturbance with unknown space–time covariance matrix, by utilizing the Rao test. The proposed Rao test without secondary data is theoretically proved to be asymptotically (large-sample in the number of temporal observations) constant false alarm rate with respect to unknown space–time covariance matrix, thanks to an asymptotic equivalence between the Rao test and the generalized likelihood ratio test. Moreover, the performance loss due to no secondary data can be remedied by appropriately increasing the temporal dimension. The performance assessment conducted by Monte Carlo simulation, also in comparison with the existing detector without secondary data, confirms the effectiveness of the proposed detectors. 相似文献
69.
In this paper, a digital filter bank structure is proposed for the reconstruction of uniformly sampled bandlimited signals from their N-th order nonuniform samples. The proposed filter bank structure is arrived at after incorporating polyphase-domain filtering operations and discrete Fourier transform (DFT) modulation to an existing filter bank framework.In this paper, an idea is also presented, so that uniform samples can be reconstructed from N-th order nonuniform samples using the structures based on recurrent nonuniform sampling. A comparison of the computational complexity and the signal-to-noise ratio (SNR) performance is also given for various structures existing in the literature. 相似文献
70.