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Complex transient dynamics of hidden attractors in a simple 4D system

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Chinese Physics B 2015年第5期24卷 270-274页

作者：党小宇李春彪包伯成武花干 college of Electronic and information {2. Nanjing University of Aeronautics and Astronautics School of Electronic & information engineering Nanjing University of Information Science & Technology School of information Science and engineering Changzhou University School of Electronic and Optical engineering Nanjing University of Science and Technology

A simple four-dimensional system with only one control parameter is proposed in this paper. The novel system has a line or no equilibrium for the global control parameter and exhibits complex transient transition behaviors of hyperchaotic attractors, periodic orbits, and unstable sinks. Especially, for the nonzero-valued control parameter, there exists no equilibrium in the proposed system, leading to the formation of various hidden attractors with complex transient dynamics. The research results indicate that the dynamics of the system shows weak chaotic robustness and depends greatly on the initial states.

关键词： transient dynamics hidden attractor equilibrium

ON THE ALMOST SURELY ASYMPTOTIC BOUNDS OF A CLASS OF ORNSTEIN-UHLENBECK PROCESSES IN INFINITE DIMENSIONS

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Journal of Systems Science & Complexity 2008年第3期21卷 416-426页

作者： Yuhong LI college of Hydropower and information {2. Huazhong University of Science and Technology Wuhan 430074 China

Given a real-valued separable M-type 2.Banach space X with the p-th power of the norm of C2.class, the almost sure asymptotic upper bounds of the solutions of the Ornstein-Uhlenbeck Processes described by the following equations {dz（t）=A（t,z（t））dt＋σ（t,z（t））dW（t）,z（0）=z0∈X,are investigated. This study generalizes the corresponding well-known finite dimensional results of Lapeyre （1989） and Mao （1992..

关键词： Almost surely asymptotic bounds infinite dimension M-type 2.Banach space Ornstein-Uhlenbeck Processes

The normal numbers of the fuzzy systems and their classes

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Science China(information Sciences) 2010年第11期53卷 2215-2229页

作者： LI HongXing1,3, YUAN XueHai1, WANG JiaYin2.& LI YuCheng3 1Faculty of Electronic information and electrical {2., Dalian university of technology, Dalian 11602., China 2.chool of Mathematical Sciences, Beijing Normal university, Beijing 100875, China 3Department of Automation, North China university of technology, Beijing 100144, China 1. Faculty of Electronic information and electrical {2. Dalian University of Technology Dalian 116024 China3. Department of Automation North China University of Technology Beijing 100144 China2. School of Mathematical Sciences Beijing Normal University Beijing 100875 China

R-fuzzy set is defined in this paper, which is regarded as the generalization of the Zadeh fuzzy set. By means of CRI method, some fuzzy systems are constructed by suitably using several kinds of R-fuzzy sets as fuzzy inference antecedents, such as interpolation fuzzy system, Bernstein fuzzy system, Lagrange fuzzy system and Hermite fuzzy system. A notion of the normal number of the fuzzy system is defined here, we have shown that all fuzzy systems are able to be classified as three classes such as the normal fuzzy systems, the regular fuzzy systems and the singular fuzzy systems under the significance of the normal numbers of fuzzy systems. Finally, the generalized Bernstein polynomial is obtained by constructing Bernstein fuzzy system, it is proved that the generalized Bernstein polynomial is uniformly convergent in C[a,b] under a weaker condition, and it is pointed out that there exist generalized Bernstein polynomials to be not convergent in C[a,b] by use of constructing a counterexample.

关键词： R-fuzzy set fuzzy system the normal number of fuzzy system universal approximation property for fuzzy system

Finite Element Analysis of Die Geometry and Process Conditions Effects on Equal Channel Angular Extrusion for β-Titanium Alloy

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Journal of Iron and Steel Research International 2012年第10期19卷 54-58页

作者： SI Jia-yong1,2. GAO Fan3, ZHANG Ji3 (1. State Key Laboratory of Powder Metallurgy, Central South university, Changsha 410083, Hunan, China 2. college of Mechanical and {2. engineering, Central South university of Forestry and technology, Changsha 410004, Hunan, China 3. High Temperature Material Research Division, Central Iron and Steel Research Institute, Beijing 100081, China) [a] State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 Hunan China [b] college of Mechanical and electrical {2. Central South University of Forestry and Technology Changsha 410004 Hunan China [c] High Temperature Material Research Division Central Iron and Steel Research Institute Beijing 100081 China

The finite element analysis was applied to evaluate the respective influences of die geometry and process conditions on plastic strain distribution for β-titanium (Ti-13V11Cr3Al) alloy during the equal channel angular extrusion (ECAE). It was found that optimum equal channel angular extrusion die geometry is strongly material dependent. Optimal strain homogeneity in the Ti-13V11Cr3Al alloy may be achieved at r (inner radius)=5 mm, R (outer radius)=3 mm. The equivalent plastic strain increases with increasing friction coefficient. And the better homogeneity of the equivalent plastic strain distribution can be achieved when friction coefficient value is lower. The faster the ram speed is, the lower the homogeneity of the equivalent plastic strain distribution is and the influence is slight. The back-pressure does not help to improve the plastic strain homogeneity, and the increasing temperature has a slightly favourable effect on the plastic strain homogeneity between 400 and 600 ℃.

关键词： equal channel angular extrusion finite element analysis die geometry β-titanium

Parameters Relevant to Bubble Detachment when Gas-injecting into Polymer Melt Flow Field

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Journal of Wuhan university of technology(Materials Science) 2005年第1期20卷 68-71页

作者：陈再良 college of Mechanical and electrical {2. Soochow University Suz hou 215021 China

The bubble deformation processes were reported when gas was injected into polyme r melt flow field in another paper, the experiments showed that the deformation was severely affected by the volume of the bubble, and in turn, for the different bubbles, several different deformation processes were presented d uring their movement along the flow channel. In addition, we could find that the magnitude of the bubble volume was dependent upon the pressure difference of th e gas injection pressure and the melt pressure. In this paper, more experimental conditions were changed to investigate the parameters relevant to the detachmen t of bubbles from the injection nozzle. The experimental results show that the p ressure difference, the melt flow velocity as well as the melt pressure were all critical for the parameters, such as the bubble detachment time, the maximum bu bble diameters and the magnitude of the bubble volume. The morphology changes of bubble were very large when the flow field was abruptly changed, and the situat ions were more complicated.

关键词： bubble morphology detachment time geometry parameters flow field

Perfect reconstruction image modulation based on BEMD and quaternionic analytic signals

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Science China(information Sciences) 2011年第12期54卷 2622-2634页

作者： QIAO LiHong 1 , NIU KaiFu 2., WANG Ning 2.& PENG LiZhong 2.1 college of information Science and {2., Henan university of technology, Zhengzhou 450001, China 2.School of Mathematical Sciences, Peking university, Beijing 100871, China 1. college of information Science and {2. Henan University of Technology Zhengzhou 450001 China2. School of Mathematical Sciences Peking University Beijing 100871 China

Image modulation represents image by meaningful characters such as image instantaneous amplitude and instantaneous frequency. A perfect reconstruction image modulation method is proposed. In detail, the bidimensional empirical mode decomposition (BEMD) is first improved to adaptively decompose image into monocomponents. Then by the quaternionic analytic method, suitable analytic signals is acquired. A new polar form is further proposed to modulate images, then seven characters are derived including instantaneous amplitude and instantaneous frequencies. We demonstrate the techniques on both synthetic and natural images, depict the needle program of the estimated frequencies and obtain the reconstructions that are the same with the original images. The applications in image segmentation and separation establish the validity of characterizing images of this type as sums of locally narrow band modulated components.

关键词： perfect reconstruction image modulation AM-FM representation BEMD quaternionic analytic signals

A relationship between the nonexistence of generalized bent functions and class groups

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Science China Mathematics 2010年第1期53卷 213-222页

作者： LIU FengMei 1,& YUE Qin 2. Department of information Research,college of information engineering,information engineering university,Zhengzhou 450002.China 2.Department of Mathematics,Nanjing university of Aeronautics and Astronautics,Nanjing 2.0016,China 1. Department of information Research College of Information Engineering Information Engineering University Zhengzhou 450002 China2. Department of Mathematics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

A new result on the nonexistence of generalized bent functions is presented by using properties of the decomposition law of primes in cyclotomic fields and properties of solutions of some Diophantine equations. At the same time,a method is given which can be used to simplify the known results. Then we give the bounds and the meaning in algebraic number theory of the parameters in our results.

关键词： generalized bent function integral basis class group genus theory

Quantum secret sharing between multiparty and multiparty with four states

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Science China(Physics,Mechanics & Astronomy) 2007年第5期50卷 572-580页

作者： YAN FengLi1, GAO Ting2.& LI YouCheng1 1 college of Physics and information {2., Hebei Normal university, Shijiazhuang 050016, China 2.college of Mathematics and information Science, Hebei Normal university, Shijiazhuang 050016, China 1. college of Physics and information {2. Hebei Normal University Shijiazhuang 050016 China 2. college of Mathematics and information Science Hebei Normal University Shijiazhuang 050016 China

A protocol of quantum secret sharing between multiparty and multiparty with four states was presented. It was shown that this protocol can nullify the Trojan horse attack with a multi-photon signal, the fake-signal attack with Einstein-Podolsky- Rosen pairs, the attack with single photons, and the attack with invisible photons. In addition, the upper bounds of the average success probabilities were given for dishonest agent eavesdropping encryption using the fake-signal attack with any two-particle entangled states.

关键词： quantum secret sharing, security, Einstein-Podolsky-Rosen pairs

Fast parallel algorithms for discrete Gabor expansion and transform based on multirate filtering

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Science China(information Sciences) 2012年第2期55卷 293-300页

作者： TAO Liang1 & GU JuanJuan2.1School of Computer Science and technology,Anhui university,Hefei 2.0039,China 2.epartment of Electronic {2. and electrical engineering,Hefei university,Hefei 2.002.,China 1. School of Computer Science and technology Anhui University Hefei 230039 China2. Department of Electronic Information and Electrical Engineering Hefei University Hefei 230022 China

The Gabor transform has long been recognized as a very useful tool for the joint time and frequency analysis in signal *** real time applications,however,were limited due to the high computational complexity of the Gabor transform *** this paper,some novel and fast parallel algorithms for the finite discrete Gabor expansion and transform are presented based on multirate *** analysis filter bank is designed for the finite discrete Gabor transform(DGT)and a synthesis filter bank is designed for the finite discrete Gabor expansion(DGE).Each of the parallel channels in the two filter banks has a unified structure and can apply the FFT and the IFFT to reduce its computational *** computational complexity of each parallel channel does not change as the oversampling rate *** fact,it is very low and depends only on the length of the input discrete signal and the number of the Gabor frequency sampling *** computational complexity of the proposed parallel algorithms is analyzed and compared with that of the major existing parallel algorithms for the finite DGT and *** results indicate that the proposed parallel algorithms for the finite DGT and DGE based on multirate filtering are very attractive for real time signal processing.

关键词： discrete Gabor expansion discrete Gabor transform critical sampling and oversampling multirate filtering analysis and synthesis filter banks