Wang S.,Beijing Jiaotong University |
Zhang X.,Sinohydro Corporation |
Wang Z.,Beijing Jiaotong University |
Lv D.,Beijing Jiaotong University
2010 International Conference on Modelling, Identification and Control, ICMIC 2010 | Year: 2010
In view of fuzzy modeling of complicate nonlinear systems, an on-line identification algorithm based on an improved T-S model is presented. Differential equation structure of the model is obtained first, then the fuzzy cluster center is corrected on-line according to the close degree of the input sample and the cluster center, and the cluster radius is refreshed in real-time according to the distance between the input sample and the cluster center. Finally, consequent parameters of the model are identified by the recursive least squares algorithm. Compared with previous identification algorithms, the on-line identification algorithm presented in this paper requires less fuzzy rules, has higher identification precision, and is simple and easy to implement. Practicability and effectiveness of the method are proved by the simulation results of the Box-Jenkins data and the boiler overheated steam temperature system. It provides a method to identify model parameters on-line for many new control strategies, such as fuzzy predictive control, adaptive control, etc.
Zhao Z.,Hubei Engineering University |
Zhao Z.,Sinohydro Corporation |
Yan P.,Hubei Engineering University |
Yan P.,Hubei University of Education |
And 6 more authors.
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2016
The vibration induced by the transient unloading of in-situ stresses (ISTU) is an important part of the eventual excavating vibration during the tunnel blasting excavation. In order to reveal the energy distribution characteristics of vibration induced by ISTU and its influence on the energy distribution of eventual excavating vibration, the energy distribution characteristics of vibration induced by ISTU under different in-situ stress levels and blasting loads were studied with the method of power spectrum analysis. The results showed that the frequency-band energy distribution of vibration induced by ISTU and blasting load were basically identical, but the main frequency of vibration induced by ISTU was lower than that induced by blasting load. The vibration induced by transient unloading of in-situ stresses was an influential factor, and it increased the low frequency component of vibration energy. The increase of in-situ stress level raised the vibration amplitude induced by ISTU and did not affect the frequency-band energy distribution. © 2016, Science Press. All right reserved.
Wang H.,China Agricultural University |
Mao X.,China Agricultural University |
Dong F.,Sinohydro Corporation
Proceedings - 2010 7th International Conference on Fuzzy Systems and Knowledge Discovery, FSKD 2010 | Year: 2010
Set pair analysis method with five-element connection number was applied for a comprehensive evaluation of the beneficial effect of water-saving renovation in irrigation area. Taken inland irrigation area in the Yellow River, Huai River and Hai River region as an example, according to their characteristics in economic, social, cultural and environmental aspects etc., the index system for a comprehensive evaluation of the beneficial effect from the water-saving project was initially established. The relative membership function was constructed by Set Pair Analysis based on five-element, where the value of evaluation index of combined effects of water-saving renovation belongs to the variable fuzzy sets 5 grades of standard evaluation criteria for the combined impact of water-saving renovation in irrigation area. The case study is carried out in Huang-Huai-Hai irrigation area for a comprehensive impact evaluation of water-saving renovations. Results show that this evaluation method is simple, reliable and the conclusion is reasonable and practical, which indicates that this method is feasible for the comprehensive evaluation of the impact of water-saving renovation and can provide theoretical basis for water-saving management in irrigation area. ©2010 IEEE.
Mao J.,Hangzhou Electric Power |
Zhao M.,Hangzhou Electric Power |
Xu H.-W.,Sinohydro Corporation
Dianli Xitong Baohu yu Kongzhi/Power System Protection and Control | Year: 2010
The snow storm disaster in southern China occurred in early 2008 left a serious impact to the line relay protection channel adhering to the transmission line, due to the poor adaptability to sudden accidents of communication channel based on optical fiber, which is widely used in field of transmission line relay protection. Based on the comparison and analysis of several kinds of commonly used protection communication channels, the principle for 220 kV transmission line protection channel scheme is adjusted. Theoretic calculation is made to demonstrate the reasonability of the new principle application in 220 kV Fangyuan-Gangyang line and further suggestions on the new principle for 220 kV transmission line protection channel scheme are given.
Li Z.-W.,Tsinghua University |
Li Z.-W.,China Institute of Water Resources and Hydropower Research |
Qin X.-H.,Sinohydro Corporation |
Fang C.-M.,China Institute of Water Resources and Hydropower Research
Shuikexue Jinzhan/Advances in Water Science | Year: 2011
The river meander is an important geomorphologic component of meandering rivers. Study of the evolution of geometrical form and channel migration of river meanders possesses high academic values. Using an integrated platform of Google Earth satellite images and AutoCAD software, a total of 136 mountain meanders and 325 alluvial meanders in eight rivers from different areas are chosen as statistical samples to define and measure geomorphologic parameters of the samples. The statistical result shows that the meander radius of curvatures in mountainous rivers is in the interval [1.7, 14.8], and the value of the curvature radius for alluvial rivers is [1.6, 38.5]. Statistically, the mean value and standard deviation of the curvature radius in alluvial rivers are much greater than those in mountainous rivers. There is not obvious skew angle tendency at bend apex in mountainous rivers, showing almost equal opportunity for both upstream and downstream development of bend apex. The number of meanders with 85 degree skew angle and greater in alluvial rivers can account for 65.5% of the total river meanders, indicating a tendency for bend apexes to grow in the upstream direction. There is a good liner relationship between the average width and the width of bend apex in alluvial rivers. A certain extent of positive correlation is found between the average river width and the meander neck width. The relationship between the relative transverse skewness and the curvature appears is also linear. These characters manifest the consistency of the shape of a planer cure in river meanders.