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181.
182.
In this letter, some sufficient conditions are obtained to guarantee recurrent neural networks with linear saturation activation functions, and time-varying delays have multiequilibria located in the saturation region and the boundaries of the saturation region. These results on pattern characterization are used to analyze and design autoassociative memories, which are directly based on the parameters of the neural networks. Moreover, a formula for the numbers of spurious equilibria is also derived. Four design procedures for recurrent neural networks with linear saturation activation functions and time-varying delays are developed based on stability results. Two of these procedures allow the neural network to be capable of learning and forgetting. Finally, simulation results demonstrate the validity and characteristics of the proposed approach. 相似文献
183.
Miyazawa M Zeng P Iso N Hirata T 《IEEE transactions on pattern analysis and machine intelligence》2006,28(7):1127-1134
The Euclidean distance transform is one of the fundamental operations in image processing. It has been widely used in computer vision, pattern recognition, morphological filtering, and robotics. This paper proposes a systolic algorithm that computes the Euclidean distance map of an N /spl times/ N binary image in 3N clocks on 2N/sup 2/ processing cells. The algorithm is designed so that the hardware resources are reduced; especially no multipliers are used and, thus, it facilitates VLSI implementation. 相似文献
184.
A new strategy for urinary sediment segmentation based on wavelet, morphology and combination method
This paper presents a strategy for segmenting urinary sediment based on wavelet, morphology and combination method. Firstly, the wavelet transforms and morphology are used to get rid of the effect of the defocusing and get the subimages that include the particles. Then based on the characteristics of the subimages, edge detection and adaptive thresholding are employed adaptively. Finally, a simplified watershed algorithm for the overlapping particles is used. The experiment results show that the method can segment the defocusing urinary sediment images effectively and precisely. 相似文献
185.
The sensitivity of a neural network's output to its input and weight perturbations is an important measure for evaluating the network's performance. In this letter, we propose an approach to quantify the sensitivity of Madalines. The sensitivity is defined as the probability of output deviation due to input and weight perturbations with respect to overall input patterns. Based on the structural characteristics of Madalines, a bottom-up strategy is followed, along which the sensitivity of single neurons, that is, Adalines, is considered first and then the sensitivity of the entire Madaline network. By means of probability theory, an analytical formula is derived for the calculation of Adalines' sensitivity, and an algorithm is designed for the computation of Madalines' sensitivity. Computer simulations are run to verify the effectiveness of the formula and algorithm. The simulation results are in good agreement with the theoretical results. 相似文献
186.
187.
188.
给出了一种异步电动机定、转子电阻参数在线实时估计方法,并将其应用于电压控制型转差频率矢量控制系统,计算机仿真结果表明该方法具有较好的参数估计效果。 相似文献
189.
High temperature characteristics of synthetic hydroxyapatite 总被引:11,自引:0,他引:11
Jiming Zhou Xingdong Zhang Jiyong Chen Shaoxian Zeng K. De Groot 《Journal of materials science. Materials in medicine》1993,4(1):83-85
The characteristics of synthetic hydroxyapatite sintered at high temperature were studied by means of X-ray diffraction, infrared and differential thermal analysis, and thermogravimetric analysis. The results show that synthetic HAp with a Ca/P ratio near 1.67 is stable when sintered in dry or wet air below 1200°C. Even after long times, no tricalcium phosphate (TCP) can be observed. Beyond 1200°C, HAp loses its OH groups gradually and is transformed to oxyapatite [Ca10O(PO4)6 or Ca(PO4)6O.]. At 1450°C oxyapatite dissociates into the products -Ca3(PO4)2, Ca2P2O7 and Ca4P2O9. 相似文献
190.
Ke Zeng Nai-Yao Zhang Wen-Li Xu 《Fuzzy Systems, IEEE Transactions on》2000,8(6):773-780
Universal approximation is the basis of theoretical research and practical applications of fuzzy systems. Studies on the universal approximation capability of fuzzy systems have achieved great progress in recent years. In this paper, linear Takagi-Sugeno (TS) fuzzy systems that use linear functions of input variables as rule consequent and their special case, named simplified fuzzy systems that use fuzzy singletons as rule consequent, are investigated. On condition that overlapped fuzzy sets are employed, new sufficient conditions for simplified fuzzy systems and linear TS fuzzy systems as universal approximators are given, respectively. Then, a comparative study on existing sufficient conditions is carried out with numeric examples 相似文献