This article describes the development and application of a multivariable neural controller for automatic ship berthing. Following a brief review of various methods employed in automatic ship control, an online traine...
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This article describes the development and application of a multivariable neural controller for automatic ship berthing. Following a brief review of various methods employed in automatic ship control, an online trained, backpropagation-based neural network controller is presented. The principal intention is to take advantage of the learning ability of neural networks, and to derive an autonomous neural control algorithm which is independent of the mathematical model of the ship. The proposed neural network controller is designed to adjust its parameters online from a direct evaluation of performance accuracy, thereby eliminating the need for off-line training and a "trainer" associated with supervised control. In addition, the nonlinearity of the rudder and the transfer lag of the propeller have been considered in the system design to increase the realism of the simulation. A series of simulation studies, which include wind disturbances and shallow water effects, have been undertaken to demonstrate the adaptive features and the robust performance of the proposed neural control scheme.
An agent based approach to induction motor control is proposed in this paper, After a short introduction in intelligent agents (controllers) special attention is given to the learning element, Two main learning paradi...
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ISBN:
(纸本)0780336275
An agent based approach to induction motor control is proposed in this paper, After a short introduction in intelligent agents (controllers) special attention is given to the learning element, Two main learning paradigms, supervised learning and reinforcement learning are used for the drive to exhibit rational behavior, Artificial neural networks are used to learn different mapping inside the intelligent current controller, Matlab(R) has been used as the simulation environment.
The popularly used backpropagation algorithm (BP) for training multilayered neural networks is generally slow and prone to getting stuck in local minima. A novel method to improve the performance of the BP by randomis...
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The popularly used backpropagation algorithm (BP) for training multilayered neural networks is generally slow and prone to getting stuck in local minima. A novel method to improve the performance of the BP by randomising the cost function is proposed. The method is effective in helping the BP algorithm to escape from local minima and therefore improve the convergence and generalization. This is demonstrated on a non-convex pattern recognition problem.
The effects of the quantization of the parameters of a learning machine are discussed. The learning coefficient should be as small as possible for a better estimate of parameters. On the other hand, when the parameter...
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The effects of the quantization of the parameters of a learning machine are discussed. The learning coefficient should be as small as possible for a better estimate of parameters. On the other hand, when the parameters are quantized, it should be relatively larger in order to avoid the paralysis of learning originated from the quantization. How to choose the learning coefficient is given in this paper from the statistical point of view.
The authors introduce a dynamic backpropagation algorithm for continuous-time dynamic neural fuzzy systems, as a generalization of the standard backpropagation algorithm for feedforward neural network systems. The pro...
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ISBN:
(纸本)0818682183
The authors introduce a dynamic backpropagation algorithm for continuous-time dynamic neural fuzzy systems, as a generalization of the standard backpropagation algorithm for feedforward neural network systems. The proposed algorithm is applied to the design and training of a fuzzy-gain-scheduler for an aircraft flight control system. The trained control system is tested on a full-fledged six-degree-of-freedom nonlinear aircraft simulation package. Simulation results show that significant improvement is achieved through training of the fuzzy-gain-scheduler by using the proposed dynamic backpropagation algorithm.
Beside the use of purely neural systems, the combination of preprocessing units and neural classifiers has been used for a variety of signal segmentation and classification tasks. Whereas this approach reduces the inp...
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Beside the use of purely neural systems, the combination of preprocessing units and neural classifiers has been used for a variety of signal segmentation and classification tasks. Whereas this approach reduces the input dimensionality as well as the complexity of the classification problem, its performance crucially depends on a proper preprocessing scheme, i.e., feature extraction. In this contribution, adaptive preprocessing units (frequency-selective quadrature filters) are proposed that can be adjusted in order to provide optimal features. The mean frequencies of the filters are tuned to minimize the classification error. Both FIR- and IIR-based filters are introduced and compared with respect to their convergence properties and the classification results. Results for the solution of an EEG segmentation task using the combined system are given.
The problem of extraction of crisp logical rules from neural networks trained with a backpropagation algorithm is solved by smooth transformation of these networks into simpler networks performing logical functions. T...
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The problem of extraction of crisp logical rules from neural networks trained with a backpropagation algorithm is solved by smooth transformation of these networks into simpler networks performing logical functions. Two constraints are included in the cost function: a regularization term inducing weight decay, and an additional term forcing the remaining weights to /spl plusmn/1 integer values. Networks with minimal number of connections are created, leading to a small number of crisp logical rules. A constructive algorithm is proposed, in which rules are generated consecutively by adding more nodes to the network. Rules that are most general, covering many training examples, are created first, followed by more specific rules, covering a few cases only. This constructive algorithm applied to the iris classification problem generates two rules with three antecedents giving 98.7% accuracy. A single rule for the mushroom problem leads to 98.52% accuracy while three additional rules allow for perfect classification. The rules found for the three monk problems classify all examples correctly.
Distance relays have attracted considerable attention for the protection of transmission lines. They are usually designed on the basis of fixed settings. Therefore, the reach of such relays is affected by the changing...
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Distance relays have attracted considerable attention for the protection of transmission lines. They are usually designed on the basis of fixed settings. Therefore, the reach of such relays is affected by the changing network conditions. The implementation of a pattern recognizer for power system diagnosis can provide great advances in the protection field. This paper demonstrates the use of an artificial neural network as a pattern classifier for distance relay operation. The backpropagation algorithm is utilized for the learning process. The scheme utilizes the magnitude of three phase voltage and current phasors as inputs. An improved performance with the use of an artificial neural network approach is experienced once the relay can operate correctly, keeping the reach when faced with different fault conditions as well as network configuration changes.
Training backpropagation (BP) networks is a time-consuming process especially on sequential machines. This has motivated the use of parallel architectures to decrease the processing time required for training. In this...
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Training backpropagation (BP) networks is a time-consuming process especially on sequential machines. This has motivated the use of parallel architectures to decrease the processing time required for training. In this paper the implementation of the BP algorithm on the Alex AVX-2 MIMD machine is investigated. Due to the high communication time caused by sending and receiving network information and due to the overhead of the message passing process, the conventional use of block-BP is not appropriate for this particular machine. Increasing the processing load of the workers with respect to the communication load will definitely increase the speedup factor. Here, we propose a block-update learning method for BP which reduces the communication time and produces results similar to those obtained with parallel block-BP.
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