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Comparative Analysis of Improving Effects of 12 Maize Populations with Improved S_1 Selection Method
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作者 孙峰成 冯勇 +6 位作者 付增娟 苏二虎 张来厚 赵瑞霞 刘志雄 石海波 李美娜 《Agricultural Science & Technology》 CAS 2014年第10期1687-1692,1713,共7页
ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of... ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of grains per row and 100-grain weight were the three important component traits of maize yield. The highest genetic increment was found in Mengqun 2, fol owed by Mengqun 4, Mengqun 1 and other 7 maize populations. Negative genetic increment was shown in Mengqun 3 and 3 introduced foreign maize populations. Some changes were shown in spikes, plant traits and genetic diversity of maize populations. Based on our results, we concluded that Mengqun 2, Mengqun 4, Zhongzong 7, Mengqun C and Mengqun A could be directly used for the line breeding by selfing for their higher genetic increment of yield and better improvement effects of other agricultural traits. Compared with these 5 populations, the improvement potential of other maize populations was limited for their lower genetic increment. 展开更多
关键词 lmproved s1 selection method Maize population Genetic gain Comparative analysis
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Fractal Method for Statistical Analysis Geological Data 被引量:2
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作者 Meng Xianguo Zhao PengdaChina University of Geosciences , Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 1991年第1期114-119,共6页
This paper establishes the phase space in the light of spacial series data , discusses the fractal structure of geological data in terms of correlated functions and studies the chaos of these data . In addition , it i... This paper establishes the phase space in the light of spacial series data , discusses the fractal structure of geological data in terms of correlated functions and studies the chaos of these data . In addition , it introduces the R/S analysis for time series analysis into spacial series to calculate the structural fractal dimensions of ranges and standard deviation for spacial series data -and to establish the fractal dimension matrix and the procedures in plotting the fractal dimension anomaly diagram with vector distances of fractal dimension . At last , it has examples of its application . 展开更多
关键词 geological data fractal method fractal dimension space series r/s analysis .
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Convergence ball and error analysis of Ostrowski-Traub’s method 被引量:1
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作者 BI Wei-hong WU Qing-biao REN Hong-min 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第3期374-378,共5页
Under the hypotheses that the second-order and third-order derivatives of a function are bounded, an estimate of the radius of the convergence ball of Ostrowski-Traub's method is obtained. An error analysis is given ... Under the hypotheses that the second-order and third-order derivatives of a function are bounded, an estimate of the radius of the convergence ball of Ostrowski-Traub's method is obtained. An error analysis is given which matches the convergence order of the method. Finally, two examples are provided to show applications of our theorem. 展开更多
关键词 Ostrowski-Traub's method nonlinear equation convergence ball estimate of radius error analysis
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Comment of Walker and Avant’s method of concept analysis 被引量:1
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作者 Hui Liu Dong-Lan Ling Irene Su 《TMR Integrative Nursing》 2018年第1期1-3,共3页
In order to promote the nursing discipline to developindependently and scientifically, nursing practice shouldbe guided by nursing theory instead of intuition andexperience of nurses [1]. Nursing theory can assist nur... In order to promote the nursing discipline to developindependently and scientifically, nursing practice shouldbe guided by nursing theory instead of intuition andexperience of nurses [1]. Nursing theory can assist nursesto deliver individual patient’s care and help to improveobservation and recognition of specific patient need, be itbiological, psychological or social [2]. Nursing theory hasdeveloped quickly and successfully in recent decadesinternationally; however, it is still in the early stage ofdevelopment in China. 展开更多
关键词 COMMENT of WALKEr Avant’s method of CONCEPT analysis
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GENERAL RELIABILITY ANALYSIS FOR TWO DIMENSIONAL SLOPES
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作者 揭敏 邓泽贤 李大海 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1998年第1期36-41,共6页
The reliability analysis, based on the reliability index method, of two dimensional slopes is generalized by taking Sarma′s acceleration as the performance function. That is to say, a general expression of the perfo... The reliability analysis, based on the reliability index method, of two dimensional slopes is generalized by taking Sarma′s acceleration as the performance function. That is to say, a general expression of the performance function is given under various kinds of slice methods, even under various shapes of slice partition, beyond the traditional vertical slice method. A simple example shows explicitly the relationship of four commonly used slice methods in the slope reliability analysis. It is also found that the results of the reliability analysis are basically consistent with those of the stability analysis based on Sarma′s method. 展开更多
关键词 reliability stability analysis two dimen sional slope sarma′s method
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R/S AND WAVELET ANALYSIS ON EVOLUTIONARYPROCESS OF REGIONAL ECONOMIC DISPARITY IN CHINA DURING PAST 50 YEARS 被引量:9
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作者 XUJian-hua LUYan +1 位作者 SUFang-lin AINan-shan 《Chinese Geographical Science》 SCIE CSCD 2004年第3期193-201,共9页
This paper shows the dynamic process of regional disparity of economic development in China in the past 50 years from a new insight by using the rescaled range statistic (R/S) analysis and wavelet analysis of the Thei... This paper shows the dynamic process of regional disparity of economic development in China in the past 50 years from a new insight by using the rescaled range statistic (R/S) analysis and wavelet analysis of the Theil index sequence with different time scales. The main conclusions are: 1) The regional disparity of economic development in China, including the inter-provincial disparity, inter-regional disparity and intra-regional disparity, has existed for many years. Theil index by the comparative price has revealed the true trend for comparative disparity of regional economic development from 1952 to 2000. 2) Decomposition of Theil index indicates that the dynamic trend of comparative inter-provincial disparity in the coastal region is in line with dynamic trend of inter-provincial disparity in the whole China. 3) The R/S analysis results tell us that during 1966-1978, the Hurst exponent H=0.504 approximate to 0.5, which indicates that in that period the evolution of comparative inter-provincial disparity of economic development showed a random characteristic, and in the other periods, i.e. 1952-1965, 1979-1990 and 1991-2000, the Hurst exponent H>0.5, which indicates that in those periods the evolution of the comparative inter-provincial disparity of economic development in China had a long-enduring characteristic. 4) By using wavelet analysis at different time scale, we arrived at a conclusion that the evolutionary process of the disparity of economic development of China is not a simple inverted U shape but a compound of several U shapes. The result tells us that the evolutionary plot of inter-provincial disparity in China follows the inverted U on the whole at the higher scale, 24 ( 16 years). That is to say, the disparity tends to rise in the first stage of economic development, and fall slowly over the peak in the second stage of economic development. However, if we shorten the time scale to 23 ( 8 years), then a link of several U shapes will appear. 展开更多
关键词 China regional economic disparity Theil index r/s analysis wavelet analysis
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Design and Analysis of Tapered Stress Joint for Top Tensioned Riser System 被引量:3
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作者 张日曦 张崎 黄一 《China Ocean Engineering》 SCIE EI 2012年第3期507-520,共14页
Stress Joint (SJ) plays a key role in the Top Tensioned Riser (TTR) system for deep water engineering. A preliminary design method of tapered SJ is proposed in the paper, which could help designers obtain accurate... Stress Joint (SJ) plays a key role in the Top Tensioned Riser (TTR) system for deep water engineering. A preliminary design method of tapered SJ is proposed in the paper, which could help designers obtain accurate design data. After a further sensitive analysis is carried out, the related parameters choice and control methods are recommended in the engineering practice. By taking the extreme environment conditions into consideration, the effects of bending stress reduction and curve control are analyzed, and the 3-D FE models are established by ABQOUS for numerical evaluation to verify the correctness of design results. At last, dynamic analysis and fatigue analysis, based on actual project, are carried out with designed stress joint. The analysis results prove the feasibility and guidance of this method in the practical engineering applications. 展开更多
关键词 stress joint s J) top tensioned riser (TTr design method parameters sensitivities dynamic analysis fatigue analysis
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R/S Analysis and its Application in the Forecast of Mine Inflows 被引量:15
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作者 YANG Yong-guo YUAN Jian-fei CHEN Suo-zhong 《Journal of China University of Mining and Technology》 EI 2006年第4期425-428,共4页
In this paper, the status quo and modeling principles of R/S analysis of non-linear theory are introduced and reviewed. Given the hydro-geological conditions of the Wutongzhuang coal mine, Hurst exponents of mine infl... In this paper, the status quo and modeling principles of R/S analysis of non-linear theory are introduced and reviewed. Given the hydro-geological conditions of the Wutongzhuang coal mine, Hurst exponents of mine inflow for the main shaft, venti- lating shaft and auxiliary shaft were obtained using R/S analysis, which are 0.772 0, 0.824 7 and 0.905 1 respectively. Since all of the three Hurst exponents are larger than 0.5, it can be concluded that the trend of mine inflow are a long-term as well as persistent problem. Based on the level of duration, the shafts can be listed in decreasing order as the auxiliary shaft, the ventilation shaft and the main shaft, which appears identical with the actual situation of the mine inflow. With R/S analysis, a new method for long-term forecasting of mine inflows is provided. 展开更多
关键词 r/s analysis Wutongzhuang coal mine mine inflow forecasting Hurst exponents
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Spatial Analysis of Fe Deposits in Fujian Province, China: Implications for Mineral Exploration 被引量:2
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作者 Ziye Wang Renguang Zuo Zhenjie Zhang 《Journal of Earth Science》 SCIE CAS CSCD 2015年第6期813-820,共8页
Spatial point pattern statistics, fractal analysis and Fry analysis in support of GIS were applied to explore the spatial distribution characteristics of mineral deposits and the spatial relationships between minerali... Spatial point pattern statistics, fractal analysis and Fry analysis in support of GIS were applied to explore the spatial distribution characteristics of mineral deposits and the spatial relationships between mineralization and geological features in Fujian Province(China). The results of Ripley's K(r) revealed a clustered distribution of Fe deposits in space with a fractal dimension of 1.38. Fry analysis showed that Fe deposits distributed mainly along a NNE-NE trend. Buffer analysis showed that most of the known Fe deposits developed within 4 km buffer zones of the NNE-NE-trending faults, Yanshanian intrusions, and Late Paleozoic marine sedimentary rocks and the carbonate formations(C–P Formation), indicating that they possibly control the spatial distribution of Fe mineralization. This is possibly because the NNE-NE-trending faults, Yanshanian intrusions, and C–P Formation provided pathways of fluids, energy and a part of metal, and zones of deposition for the Fe mineralization, respectively. The fractal relation of the number of Fe deposits occurring within the buffer zones of geological features was observed. The fractal dimension suggested that the significance of Yanshanian intrusions and C–P Formation are greater than that of NNE-NE-trending faults in controlling the formation of Fe mineralization. These findings are useful for better understanding the formation of the mineralization and provide significant information for further mineral exploration. 展开更多
关键词 ripley's K(r function fractal dimension Fry analysis Fe deposits Fujian.
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Multi-scale and multi-fractal analysis of pressure fluctuation in slurry bubble column bed reactor 被引量:1
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作者 王兴军 胡立舜 +3 位作者 沈军杰 余志楠 王辅臣 于遵宏 《Journal of Central South University of Technology》 EI 2007年第5期696-700,共5页
The Daubechies second order wavelet was applied to decompose pressure fluctuation signals with the gas flux varying from 0.18 to 0.90 m3/h and the solid mass fraction from 0 to 20% and scales 1?9 detail signals and th... The Daubechies second order wavelet was applied to decompose pressure fluctuation signals with the gas flux varying from 0.18 to 0.90 m3/h and the solid mass fraction from 0 to 20% and scales 1?9 detail signals and the 9th scale approximation signals. The pressure signals were studied by multi-scale and R/S analysis method. Hurst analysis method was applied to analyze multi-fractal characteristics of different scale signals. The results show that the characteristics of mono-fractal under scale 1 and scale 2, and bi-fractal under scale 3?9 are effective in deducing the hydrodynamics in slurry bubbling flow system. The measured pressure signals are decomposed to micro-scale signals, meso-scale signals and macro-scale signals. Micro-scale and macro-scale signals are of mono-fractal characteristics, and meso-scale signals are of bi-fractal characteristics. By analyzing energy distribution of different scale signals,it is shown that pressure fluctuations mainly reflects meso-scale interaction between the particles and the bubble. 展开更多
关键词 pressure fluctuation r/s analysis MULTI-sCALE MULTI-FrACTAL bubble column bed reactor
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Ergodic sensitivity analysis of one-dimensional chaotic maps 被引量:1
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作者 Adam A.Śliwiak Nisha Chandramoorthy Qiqi Wang 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2020年第6期438-447,共10页
Sensitivity analysis in chaotic dynamical systems is a challenging task from a computational point of view.In this work,we present a numerical investigation of a novel approach,known as the space-split sensitivity or ... Sensitivity analysis in chaotic dynamical systems is a challenging task from a computational point of view.In this work,we present a numerical investigation of a novel approach,known as the space-split sensitivity or S3 algorithm.The S3 algorithm is an ergodic-averaging method to differentiate statistics in ergodic,chaotic systems,rigorously based on the theory of hyperbolic dynamics.We illustrate S3 on one-dimensional chaotic maps,revealing its computational advantage over na?ve finite difference computations of the same statistical response.In addition,we provide an intuitive explanation of the key components of the S3 algorithm,including the density gradient function. 展开更多
关键词 sensitivity analysis Chaotic systems ErGODICITY space-split sensitivity(s3)method
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Finite element analysis of slope stability by expanding the mobilized principal stress Mohr's circles-Development,encoding and validation 被引量:2
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作者 Djillali Amar Bouzid 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第4期1165-1179,共15页
In recent years,finite element analysis is increasingly being proposed in slope stability problems as a competitive method to traditional limit equilibrium methods(LEMs)which are known for their inherent deficiencies.... In recent years,finite element analysis is increasingly being proposed in slope stability problems as a competitive method to traditional limit equilibrium methods(LEMs)which are known for their inherent deficiencies.However,the application of finite element method(FEM)to slope stability as a strength reduction method(SRM)or as finite element limit analysis(FELA)is not always a success for the drawbacks that characterize both methods.To increase the performance of finite element analysis in this problem,a new approach is proposed in this paper.It consists in gradually expanding the mobilized stress Mohr’s circles until the soil failure occurs according to a prescribed non-convergence criterion.The present approach called stress deviator increasing method(SDIM)is considered rigorous for three main reasons.Firstly,it preserves the definition of the factor of safety(FOS)as the ratio of soil shear strength to the mobilized shear stress.Secondly,it maintains the progressive development of shear stress resulting from the increase in the principal stress deviator on the same plane,on which the shear strength takes place.Thirdly,by introducing the concept of equivalent stress loading,the resulting trial stresses are checked against the violation of the actual yield criterion formed with the real strength parameters rather than those reduced by a trial factor.The new numerical procedure was encoded in a Fortran computer code called S^(4)DINA and verified by several examples.Comparisons with other numerical methods such as the SRM,gravity increasing method(GIM)or even FELA by assessing both the FOS and contours of equivalent plastic strains showed promising results. 展开更多
关键词 slope stability Finite element analysis strength reduction method(srM) stress point-based factor of safety(FOs) Limit equilibrium method(LEM) stress deviator Mohrs circle Plastic strain
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Quantitative analysis of 3D vasculature for evaluation of angiogenesis in liver fibrosis with SR-μCT 被引量:1
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作者 Hai Tan Yi Fu +2 位作者 Da-Dong Wang Xi Zhang Ti-Qiao Xiao 《Nuclear Science and Techniques》 SCIE CAS CSCD 2016年第5期255-263,共9页
The micro-CT imaging of vasculature is a powerful tool for evaluation of angiogenesis,a prominent characteristic of hepatic fibrosis.The segment or bifurcation density,which is usually adopted to evaluate the degree o... The micro-CT imaging of vasculature is a powerful tool for evaluation of angiogenesis,a prominent characteristic of hepatic fibrosis.The segment or bifurcation density,which is usually adopted to evaluate the degree of hepatic fibrosis,does not always work and may lead to incorrect assessment,especially when the threedimensional vasculature obtained is imperfect in sample preparation or image collection.In this paper,we propose a new parameter to solve this problem.The experimental results demonstrate that the method is robust and reliable,and is practical for angiogenesis evaluation,despite of image data imperfections.This quantitative analysis method can be extended to investigate other kinds of diseases in which vasculature change is a key indicator. 展开更多
关键词 血管生成 肝纤维化 CT成像 评价 三维 定量分析方法 图像采集 样品制备
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A search for evidence of small-scale inhomogeneities in dense cores from line profile analysis
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作者 Lev Pirogov 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第8期97-102,共6页
In order to search for intensity fluctuations on the HCN(1-0) and HCO+(1-0) line pro- files, which could arise due to possible small-scale inhomogeneous structure, long-term observations of high-mass star-forming... In order to search for intensity fluctuations on the HCN(1-0) and HCO+(1-0) line pro- files, which could arise due to possible small-scale inhomogeneous structure, long-term observations of high-mass star-forming cores S140 and S199 were carried out. The data were processed by the Fourier filtering method. Line temperature fluctuations that exceed the noise level were detected. Assuming the cores consist of a large number of randomly moving small thermal fragments, the total number of frag- ments is - 4 × 106 for the region with linear size - 0.1 pc in S140 and - 106 for the region with linear size - 0.3 pc in S 199. Physical parameters of fragments in S 140 were obtained from detailed modeling of the HCN emission in the framework of the clumpy cloud model. 展开更多
关键词 LINEs profiles - molecular data - methods data analysis - IsM clouds - IsM molecules - IsM structure - IsM individual objects s 140)
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Efficient Fast Independent Component Analysis Algorithm with Fifth-Order Convergence
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作者 Xuan-Sen He Tiao-Jiao Zhao Fang Wang 《Journal of Electronic Science and Technology》 CAS 2011年第3期244-249,共6页
Independent component analysis (ICA) is the primary statistical method for solving the problems of blind source separation. The fast ICA is a famous and excellent algorithm and its contrast function is optimized by ... Independent component analysis (ICA) is the primary statistical method for solving the problems of blind source separation. The fast ICA is a famous and excellent algorithm and its contrast function is optimized by the quadratic convergence of Newton iteration method. In order to improve the convergence speed and the separation precision of the fast ICA, an improved fast ICA algorithm is presented. The algorithm introduces an efficient Newton's iterative method with fifth-order convergence for optimizing the contrast function and gives the detail derivation process and the corresponding condition. The experimental results demonstrate that the convergence speed and the separation precision of the improved algorithm are better than that of the fast ICA. 展开更多
关键词 Index Terms---Blind source separation fast independent component analysis fifth-order convergence independent component analysis Newton's iterative method.
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Stability Analysis of Periodic Solutions of Some Duffing’s Equations
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作者 E. O. Eze U. E. Obasi E. U. Agwu 《Open Journal of Applied Sciences》 2019年第4期198-214,共17页
In this paper, some stability results were reviewed. A suitable and complete Lyapunov function for the hard spring model was constructed using the Cartwright method. This approach was compared with the existing result... In this paper, some stability results were reviewed. A suitable and complete Lyapunov function for the hard spring model was constructed using the Cartwright method. This approach was compared with the existing results which confirmed a superior global stability result. Our contribution relies on its application to high damping door constructions. (2010 Mathematics Subject Classification: 34B15, 34C15, 34C25, 34K13.) 展开更多
关键词 stability analysis Duffing’s EQUATIONs PErIODIC sOLUTIONs MATCAD Cartwright method
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An Empirical Analysis of the Growth of IT Enterprises in China
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作者 Changqi Tao 《Chinese Business Review》 2004年第3期9-16,共8页
The paper makes an empirical analysis on the main factors affecting IT corporate growth-human resource and R&D. By using data of China's listed IT companies, we focus on the relationship among corporate value (net ... The paper makes an empirical analysis on the main factors affecting IT corporate growth-human resource and R&D. By using data of China's listed IT companies, we focus on the relationship among corporate value (net return of equity, ROE) or development of COl'porate value (Tobin's Q) and manager's salary, R&D fee, R&D employee etc. The conclusion shows that development of corporate value (Tobin's Q) has correlativity positive with the plurality of board chairman and general manager, independent directors' proportion, R&D fee, and R&D employees while it is non-obvious positive with salary of superior managers, holding stocks of general manager, capital investment, and negative with corporate scale. The conclusion is accordant with the development status of Chinese IT corporate. 展开更多
关键词 IT Corporation Tobin's Q human resource r&D empirical analysis
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Stability analysis of the simplest Takagi-Sugeno fuzzy control system using circle criterion
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作者 Lu Hongqian Huang Xianlin +2 位作者 Gao X. Z. Ban Xiaojun Yin Hang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期311-319,共9页
A frequency-domain-based sufficient condition is derived to guarantee the globally asymptotic stability of the simplest Takagi-Sugeno (T-S) fuzzy control system by using the circle criterion. The analysis is perform... A frequency-domain-based sufficient condition is derived to guarantee the globally asymptotic stability of the simplest Takagi-Sugeno (T-S) fuzzy control system by using the circle criterion. The analysis is performed in the frequency domain, and hence the condition is of great significance when the frequency-response method, which is widely used in the linear control theory and practice, is employed to synthesize the simplest T-S fuzzy controller. Besides, this sufficient condition is featured by a graphical interpretation, which makes the condition straightforward to be used. Comparisons are drawn between the performance of the simplest T-S fuzzy controller and that of the linear compensator. Two numerical examples are presented to demonstrate how this sufficient condition can be applied to both stable and unstable plants. 展开更多
关键词 T-s fuzzy controller stability analysis Circle criterion Frequency response method.
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