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China Welding 2016年第1期25卷 21-29页

作者：王莹吕小青王立君 School of Materials Science and Engineering Tianjin University

This paper introduced the basic theory and algorithm of the surrogate data method, which proposed a rigorous way to detect the random and seemingly stochastic characteristics in a system. The Gaussian data and the Rossler data were used to show the availability and effectivity of this method. According to the analysis by this method based on the short-circuiting current signals under the conditions of the same voltage and different wire feed speeds, it is demonstrated that the electrical signals time series exhibit apparently randomness when the welding parameters do not match. However, the electrical signals time series are deterministic when a match is found. The stability of short-circuiting transfer process could be judged exactly by the method of surrogate data.

关键词： CO2 welding surrogate data method deterministic and stochastic analysis short-circuiting transfer stability

Testing for Nonlinearity in Dynamic Characteristics of Vertical Upward Oil-Gas-Water Three-phase Bubble and Slug Flows

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Chinese Journal of Chemical Engineering 2012年第5期20卷 870-882页

作者：朱雷金宁德高忠科杜萌王振亚 School of Electrical Engineering&Automation Tianjin University

Based on the conductance fluctuation signals measured from vertical upward oil-gas-water three-phase flow experiment, time frequency representation and surrogate data method were used to investigate dynamical characteristics of oil-in-water type bubble and slug flows. The results indicate that oil-in-water type bubble flow will turn to deterministic motion with the increase of oil phase fraction f o and superficial gas velocity U sg under fixed flowrate of oil-water mixture Q mix . The dynamics of oil-in-water type slug flow becomes more complex with the increase of U sg under fixed flowrate of oil-water mixture. The change of f o leads to irregular influence on the dynamics of slug flow. These interesting findings suggest that the surrogate data method can be a faithful tool for characterizing dynamic characteristics of oil-in-water type bubble and slug flows.

关键词： oil-gas-water three-phase flow conductaJace fluctuating signals time-frequency representation surrogate data method

Analysis of Non-stationary Signals Based on Nonlinear Chaotic Theories

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International Journal of Plant Engineering and Management 2011年第4期16卷 249-254页

作者： HAN Qing-peng College of Mechanical Engineering Liaoning Science and Technology University Anshan 114051 P. R. China

In the paper, two nonlinear parameter estimation methods based on chaotic theory, surrogate data method and Lyapunov exponents, are used to distinguish the difference of non-stationary signals. After brief introducting of the corresponding algorithms, two typical different non-stationary signals with different nonlinear constraining boundaries are taken to be compared by using the above two methods respectively. The obtained results demonstrate that the apparently similar signals are distinguished effectively in a quantitative way by applying above nonlinear chaotic analyses.

关键词： non-stationary signals surrogate data method Lyapunov exponents

Detecting the Nonlinearity of Fish Acoustic Signals

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Journal of Ocean University of China 2006年第3期5卷 278-282页

作者： REN Xinmin YIN Li Information Science and Engineering College Ocean University of China Qingdao 266071 P. R. China Institute of Acoustics Chinese Academy of Scienees Beijing 100080 P.R. China

This paper discusses the nonlinearity of fish acoustic signals by using the surrogate data method. We compare the difference of three test statistics - time-irreversibility Trey, correlation dimension D2 and auto mutual information function I between the original data and the surrogate data. We come to the conclusion that there exists nonlinearity in the fish acoustic signals and there exist deterministic nonlinear components; therefore nonlinear dynamic theory can be used to analyze fish acoustic signals.

关键词： fish acoustic signals nonlinearity surrogate data method null hypothesis test statistics