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Chinese Physics B 2014年第1期23卷 480-488页

作者： Hamid Reza Abbasi Ahmad Gholami Seyyed Hamid Fathi Ataollah Abbasi Iran University of Science & Technology Electrical & Electronic Engineering Department Narmak *** Tehran Iran Amirkabir University Electrical Engineering Department Tehran 64540 Iran

In this paper, controlling chaos when chaotic ferroresonant oscillations occur in a voltage transformer with nonlin- ear core loss model is performed. The effect of a parallel metal oxide surge arrester on the ferroresonance oscillations of voltage transformers is studied. The metal oxide arrester （MOA） is found to be effective in reducing ferroresonance chaotic oscillations. Also the multiple scales method is used to analyze the chaotic behavior and different types of fixed points in ferroresonance of voltage transformers considering core loss. This phenomenon has nonlinear chaotic dynamics and includes sub-harmonic, quasi-periodic, and also chaotic oscillations. In this paper, the chaotic behavior and various ferroresonant oscillation modes of the voltage transformer is studied. This phenomenon consists of different types of bifur- cations such as period doubling bifurcation （PDB）, saddle node bifurcation （SNB）, Hopf bifurcation （HB）, and chaos. The dynamic analysis of ferroresonant circuit is based on bifurcation theory. The bifurcation and phase plane diagrams are il- lustrated using a continuous method and linear and nonlinear models of core loss. To analyze ferroresonance phenomenon, the Lyapunov exponents are calculated via the multiple scales method to obtain Feigenbaum numbers. The bifurcation diagrams illustrate the variation of the control parameter. Therefore, the chaos is created and increased in the system.

关键词： ferroresonance chaos theory metal oxide arrester Lyapunov exponent

Arrhythmia Detection by Using chaos theory with Machine Learning Algorithms

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Computers, Materials & Continua 2024年第6期79卷 3855-3875页

作者： Maie Aboghazalah Passent El-kafrawy Abdelmoty M.Ahmed Rasha Elnemr Belgacem Bouallegue Ayman El-sayed Math and Computer Science Department Faculty of ScienceMenoufia UniversityShebin El-komEgypt College of Engineering Computer Science DepartmentEffat UniversityJeddahKingdom of Saudi Arabia Department of Computer Engineering College of Computer ScienceKing Khalid UniversityAbha61421Saudi Arabia Computer Science and Engineering Department Faculty of Electronic EngineeringMenoufia UniversityShebin El-komEgypt Climate Change Information Center and Expert Systems Agriculture Research CenterGizaEgypt

Heart monitoring improves life ***(ECGs or EKGs)detect heart *** learning algorithms can create a few ECG diagnosis processing *** first method uses raw ECG and time-series *** second method classifies the ECG by patient *** third technique translates ECG impulses into Q waves,R waves and S waves(QRS)features using richer *** ECG signals vary naturally between humans and activities,we will combine the three feature selection methods to improve classification accuracy and *** using all three approaches have not been examined till *** researchers found that Machine Learning(ML)techniques can improve ECG *** study will compare popular machine learning techniques to evaluate ECG *** algorithms—Support Vector Machine(SVM),Decision Tree,Naive Bayes,and Neural Network—compare categorization *** plus prior knowledge has the highest accuracy(99%)of the four ML *** characteristics failed to identify signals without chaos *** 99.8%classification accuracy,the Decision Tree technique outperformed all previous experiments.

关键词： ECG extraction ECG leads time series prior knowledge and arrhythmia chaos theory QRS complex analysis machine learning ECG classification

Improved PSO algorithm based on chaos theory and its application to design flood hydrograph

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Water Science and Engineering 2010年第2期3卷 156-165页

作者： Si-fang DONG Zeng-chuan DONG Jun-jian MA Kang-ning CHEN State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 P. R. China Department of Remote Sensing Center China Institute of Water Resources and Hydropower Research Beijing 100044 P. R. China

The deficiencies of basic particle swarm optimization （bPSO） are its ubiquitous prematurity and its inability to seek the global optimal solution when optimizing complex high-dimensional functions. To overcome such deficiencies, the chaos-PSO （COSPSO） algorithm was established by introducing the chaos optimization mechanism and a global particle stagnation-disturbance strategy into bPSO. In the improved algorithm, chaotic movement was adopted for the particles＇ initial movement trajectories to replace the former stochastic movement, and the chaos factor was used to guide the particles＇ path. When the global particles were stagnant, the disturbance strategy was used to keep the particles in motion. Five benchmark optimizations were introduced to test COSPSO, and they proved that COSPSO can remarkably improve efficiency in optimizing complex functions. Finally, a case study of COSPSO in calculating design flood hydrographs demonstrated the applicability of the improved algorithm.

关键词： particle swarm optimization chaos theory initialization strategy of chaos factor global particle stagnation-disturbance strategy design flood hydrograph

Research on General Permutation Encryption Module Based on chaos theory

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International Journal of Technology Management 2014年第7期 58-61页

作者： Sun Wenjie State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou Henan 102206

Replacement and substitution encryption are two basic types of encryption historically. The classical encryption algorithm has been compromised now, but they still can play special role for modem cryptnlogy. For example, in digital image encryption system, substitution can disrupt the original order of the images and eliminate the correlation of image information which not only can realize security of images, but also can resist intentional attack and destruction of clipping and noise. And transposition transformation is introduced into the design of block ciphers. The substitution has the feature of high efficiency and resistance, which makes it meet the specific requirements of encryption. So substitution cypher can be applied to modern encryption system.

关键词： chaos theory general substitution encryption.

Research on Stream Cipher Model Based on chaos theory

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International Journal of Technology Management 2013年第2期 91-93页

作者： Sun Wenjie State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou Henan 102206

chaos is a similar and random process which is very sensitive to initial value in deterministic system. It is a performance of nonlinear dynamical system with built-in randomness. Combined with the advantages and disadvantages of the present chaos encryption model, the paper proposes a chaotic stream cipher model based on chaos theory, which not only overcomes finite precision effect, but also improves the randomness of chaotic system and output sequence. The Sequence cycle theory generated by the algorithm can reach more than 10600 at least, which completely satisfies the actual application requirements of stream cipher system.

关键词： chaos theory stream cipher algorithm

Application of chaos theory and Data Mining to Seizure Detection of Epilepsy

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Application of Chaos Theory and Data Mining to Seizure Detec...

Detection of Weak signal and Fusion of Neural Network Data in Ultrasonic System Using chaos theory

The 2012 4th International Conference on Machine Learning and Computing（ICMLC 2012）

作者： Chien-Liang Chen Jenn-Long Liu Jhih-Yu Syu Dept.of Information Management Fortune Institute TechnologyKaohsiung 831Taiwan Dept.of Information Engineering I-Shou UniversityKaohsiung 840Taiwan Dept.of Information Management I-Shou UniversityKaohsiung 840Taiwan

This study applies chaos theory to investigate the seizure detection of epilepsy with three groups of data （Groups H,S and E）,showing the electroencephalography （EEG） changes of *** three groups,Group H （normal state）,Group S （during seizures） and Group E （after seizures）,contain 100 series of EEG signals *** detected data are processed by chaotic theory to transform the signals to four parameters with Delay Time （τ）,Embedding Dimension （dm）,Correlation Dimension （CD） value,and Largest Lyapunov Exponent （LLE）.Furthermore,well-known classification software for data mining,termed See5 based on entropy theory,is used to find out the classification rules for the EEG signals of epilepsy patients.

关键词： chaos theory Epilepsy Decision Tree Classification Rule

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Detection of Weak signal and Fusion of Neural Network Data i...

Kinematic Analysis of the Neck and Upper Extremities During Walking in Healthy Young Adults

第二届仪器科学与技术国际学术研讨会

作者： Zhang Shuqing Zhang Jingchao Li Xin Yanshan University Qinhuangdao

＜正＞ Within the frame work of ultrasonic detecting system, a theoretical method was proposed for extracting weak signals from the background of strong noise using the chaos character first. Taking the advantage of sensibility of the chaos vibrator to valuable signals and the strong immunity to noise, the detected signals can be made available from all kinds of complex noises. Multi-sensor data fusion technology is used for information processing, using artificial neural network. The best structure of network was established for the accuracy and training rate required for neural network,.

关键词： ultrasonic chaos theory neural network multi-sensor data fusion

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Journal of Bionic Engineering 2011年第3期8卷 305-312页

作者： Kwon Son Junghong Park Seonghun Park School of Mechanical Engineering Pusan National University Busan 609-735 Republic of Korea

The objective of this paper is to quantify the local stabilities of the neck and upper extremities （right/left shoulders and right/left elbows）, and investigate differences between linear and nonlinear measurements of the associated joint motions and differences in the local stability between the upper and lower extremities. This attempt involves the calculation of a nonlinear parameter, Lyapunov Exponent （LE）, and a linear parameter, Range of Motion （ROM）, during treadmill walking in conj unction with a large population of healthy subjects. Joint motions of subjects were captured using a three-dimensional motion-capture system. Then mathematical chaos theory and the Rosenstein algorithm were employed to calculate LE of joints as the extent of logarithmic divergence between the neighboring state-space trajectories of flexion-extension angles. LEs computed over twenty males and twenty females were 0.037~0.023 for the neck, 0.043＋0.021 for the right shoulder, 0.045i0.030 for the left shoulder, 0.032i0.021 for the right elbow, and 0.034~0.026 for the left elbow. Although statistically significant difference in the ROM was observed between all pairs of the neck and upper extremity joints, differences in the LE between all pairs of the joints as well as between males and females were not statistically significant. Between the upper and lower extremities, LEs of the neck, shoulder, and elbow were significantly smaller than those of the hip （-0.064） and the knee （-0,062）. These results indicate that a statistical difference in the local stability between the upper extremity joints is not significant. However, the different result between the ROM and LE gives a strong rationale for applying both linear and nonlinear tools together to the evaluation of joint movement. The LEs of the joints calculated from a large population of healthy subjects could provide normative values for the associated joints and can be used to evaluate the recovery progress of patients with joint rel

关键词： kinematic analysis Lyapunov exponent range of motion chaos theory upper extremities

Hybrid optimization algorithm based on chaos,cloud and particle swarm optimization algorithm

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Journal of Systems Engineering and Electronics 2013年第2期24卷 324-334页

作者： Mingwei Li Haigui Kang Pengfei Zhou Weichiang Hong Faculty of Infrastructure Engineering Dalian University of Technology Department of Information Management Oriental Institute of Technology

As for the drop of particle diversity and the slow convergent speed of particle in the late evolution period when particle swarm optimization（PSO） is applied to solve high-dimensional multi-modal functions,a hybrid optimization algorithm based on the cat mapping,the cloud model and PSO is *** the PSO algorithm evolves a certain of generations,this algorithm applies the cat mapping to implement global disturbance of the poorer individuals,and employs the cloud model to execute local search of the better individuals;accordingly,the obtained best individuals form a new *** this new swarm,the evolution operation is maintained with the PSO algorithm,using the parameter of pop distr to balance the global and local search capacity of the algorithm,as well as,adopting the parameter of mix gen to control mixing times of the *** comparative analysis is carried out on the basis of 4 functions and other *** indicates that this algorithm shows faster convergent speed and better solving precision for solving functions particularly those high-dimensional multi-modal ***,the suggested values are proposed for parameters pop distr and mix gen applied to different dimension functions via the comparative analysis of parameters.

关键词： particle swarm optimization(PSO) chaos theory cloud model hybrid optimization

Artificial Bee Colony Algorithm-based Parameter Estimation of Fractional-order Chaotic System with Time Delay

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IEEE/CAA Journal of Automatica Sinica 2017年第1期4卷 107-113页

作者： Wenjuan Gu Yongguang Yu Wei Hu School of Economics and Management Beijing Jiaotong University School of Science Beijing Jiaotong University

It is an important issue to estimate parameters of fractional-order chaotic systems in nonlinear science, which has received increasing interest in recent years. In this paper, time delay and fractional order as well as system's parameters are concerned by treating the time delay and fractional order as additional parameters. The parameter estimation is converted into a multi-dimensional optimization problem. A new scheme based on artificial bee colony ABC algorithm is proposed to solve the optimization problem. Numerical experiments are performed on two typical time-delay fractional-order chaotic systems to verify the effectiveness of the proposed method. © 2014 Chinese Association of Automation.

关键词： chaos theory Chaotic systems Numerical methods Optimization Time delay Timing circuits