This paper presents a composite disturbance rejection control strategy for high purity binary distillation column with complex characteristics, such as couplings, non-minimum phase, model mismatches and external distu...
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This paper presents a composite disturbance rejection control strategy for high purity binary distillation column with complex characteristics, such as couplings, non-minimum phase, model mismatches and external disturbances. Main goal of the controller is to get the desired top and bottom compositions in presence of both model mismatches and external disturbances. The composite controller includes neural network inverse controller (NNIC) and neural network disturbance observer (NNDOB) both using radial basis function network (RBFN). The inverse model of the system is identified by RBFN, whose stability is proved via the Lyapunov function analysis. And a rigorous analysis is also given to show why the NNDOB can effectively suppress the disturbances. Performance of the proposed scheme is compared with PID and NNIC schemes in two cases. The feasibility, effectiveness and disturbance rejection property of the proposed method are demonstrated by the simulation studies.
For a class of nonlinear differential-algebraic equations subsystems, whose index is one and interconnection is local measurable, the inversion control problem is studied by extending Interactor algorithm of nonlinear...
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For a class of nonlinear differential-algebraic equations subsystems, whose index is one and interconnection is local measurable, the inversion control problem is studied by extending Interactor algorithm of nonlinear ordinary differential equations systems. Compared with existing results, the proposed method in this paper bears better realization because of no complex matrix transformation being needed. Firstly, the definition of right inverse systems is presented. Secondly, an extended Interactor algorithm is proposed to judge whether the controlled systems are invertable. Once the controlled systems are invertable, a physical realizable right inverse system is constructed, with which the controlled systems are made linearization and decoupled so that linear control methods can be applied. Finally, an excitation controller is designed for one synchronous generator of multi-machine power systems based on the proposed method in this paper. The simulation results illustrate the validity of the proposed control method in this paper.
The computation of stereo depth is a very important field of computer vision. Aiming at solving the problem of low accuracy of traditional Census-based stereo matching algorithm, a variable support-weight approach for...
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ISBN:
(纸本)9781467321969
The computation of stereo depth is a very important field of computer vision. Aiming at solving the problem of low accuracy of traditional Census-based stereo matching algorithm, a variable support-weight approach for visual correspondence search based on modified Census transform is proposed in this paper. On the basis of analyzing defects of the traditional Census transform, a modified Census transform algorithm using average value of minimum evenness sub-area as a reference instead of the center pixel intensity as a reference is raised which enhances robustness of the algorithm. The matching accuracy is improved by weighting the average value and the standard deviation of Hamming distances in a block. The experiment results indicate that the proposed approach works better than traditional ones. Accurate disparities can be obtained even in the depth discontinuities regions.
Social media is widely utilized in the tobacco control campaigns. It is a great challenge to evaluate the efficiency of tobacco control policies on social network sites and find gaps among tobacco-oriented social netw...
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The polymer electrolyte membrane(PEM) fuel cell has been regarded as a potential alternative power source,and a model is necessary for its design,control and power management.A hybrid dynamic model of PEM fuel cell,...
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The polymer electrolyte membrane(PEM) fuel cell has been regarded as a potential alternative power source,and a model is necessary for its design,control and power management.A hybrid dynamic model of PEM fuel cell,which combines the advantages of mechanism model and black-box model,is proposed in this *** improve the performance,the static neural network and variable neural network are used to build the black-box *** static neural network can significantly improve the static performance of the hybrid model,and the variable neural network makes the hybrid dynamic model predict the real PEM fuel cell behavior with required ***,the hybrid dynamic model is validated with a 500 W PEM fuel *** static and transient experiment results show that the hybrid dynamic model can predict the behavior of the fuel cell stack accurately and therefore can be effectively utilized in practical application.
Dynamic image stabilization precision of an optical image-stable device is a key technical ***,a fast dynamic image stabilization precision test system for an optical image-stable device is developed.A large-aperture ...
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Dynamic image stabilization precision of an optical image-stable device is a key technical ***,a fast dynamic image stabilization precision test system for an optical image-stable device is developed.A large-aperture collimator with a designed cross divisional board is used to simulate the infinity *** image-stable device is installed on the motion simulator with six degrees of freedom which is used to simulate the moving state of the *** CCD camera installed behind the eyepiece lens of the image-stable device acquires images rapidly and in real *** local energy maxima center of the cross light spot can be acquired accurately through the proposed algorithm using the Hessian *** addition,to deal with the CCD non-uniformity,an adaptive non-uniformity correction algorithm based on bi-dimensional empirical mode decomposition is *** actual test results for the proposed method show that the test error of dynamic image stabilization is less than 0.7,and the time for the frame image acquisition and processing is less than 10 ms,which demonstrates the effectiveness of the test system.
Recently, the rapidly increasing demand for cutting of large-sized flat work pieces calls for the emergence of large waterjet cutting machine tools. Multi-bridge waterjet cutting machines are one of the preferred solu...
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This paper presents a deadlock prevention method for a class of flexible manufacturing systems (FMS) where deadlocks are caused by unmarked siphons in the Petri net. In order to prevent deadlock, we propose a new algo...
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This paper presents a deadlock prevention method for a class of flexible manufacturing systems (FMS) where deadlocks are caused by unmarked siphons in the Petri net. In order to prevent deadlock, we propose a new algorithm to forbid the bad states maximally at each iteration so that the number of reachable states comes nearest to the optimal one. First, compute a maximal unmarked siphon by using an MIP algorithm. Then, obtain a subnet based on the unmarked siphon. Next, compute all minimal siphons of the subnet and add monitors to control them. We choose the right minimal siphon to control at last by comparison of their state number. This strategy is an iterative method. With the development of this algorithm, we avoid the redundant monitors, and hence significantly improve the computational efficiency. Finally, the proposed method is illustrated by using an example.
An implementation of adaptive filtering, composed of an unsupervised adaptive filter (UAF), a multi-step forward linear predictor (FLP), and an unsupervised multi-step adaptive predictor (UMAP), is built for sup...
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An implementation of adaptive filtering, composed of an unsupervised adaptive filter (UAF), a multi-step forward linear predictor (FLP), and an unsupervised multi-step adaptive predictor (UMAP), is built for suppressing impulsive noise in unknown circumstances. This filtering scheme, called unsupervised robust adaptive filter (URAF), possesses a switching structure, which ensures the robustness against impulsive noise. The FLP is used to detect the possible impulsive noise added to the signal, if the signal is "impulse-free", the filter UAF can estimate the clean sig- nal. If there exists impulsive noise, the impulse corrupted samples are replaced by predicted ones from the FLP, and then the UMAP estimates the clean signal. Both the simulation and experimental results show that the URAF has a better rate of convergence than the most recent universal filter, and is effective to restrict large disturbance like impulsive noise when the universal filter fails.
Target tracking is one of the applications of wireless sensor networks(WSNs).It is assumed that each sensor has a limited range for detecting the presence of the object,and the network is sufficiently dense so that ...
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Target tracking is one of the applications of wireless sensor networks(WSNs).It is assumed that each sensor has a limited range for detecting the presence of the object,and the network is sufficiently dense so that the sensors can cover the area of *** to the limited battery resources of sensors,there is a tradeoff between the energy consumption and tracking *** solve this problem,this paper proposes an energy efficient tracking *** on the cooperation of dispatchers,sensors in the area are scheduled to switch their working mode to track the *** energy consumed in active mode is higher than that in monitoring or sleeping mode,for each sampling interval,a minimum set of sensors is woken up based on the select ***,other sensors keep in sleeping *** analysis and simulation results show that the proposed algorithm provides a better performance than other existing approaches.
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