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Improved Oustaloup approximation of fractional-order operators using adaptive chaotic particle swarm optimization

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Journal of Systems Engineering and Electronics 2012年第1期23卷 145-153页

作者： zhe gao Xiaozhong Liao School of Automation Beijing Institute of Technology Beijing 100081 P. R. China

A rational approximation method of the fractional-order derivative and integral operators is proposed. The turning fre- quency points are fixed in each frequency interval in the standard Oustaloup approximation. In the improved Oustaloup method, the turning frequency points are determined by the adaptive chaotic particle swarm optimization （PSO）. The average velocity is proposed to reduce the iterations of the PSO. The chaotic search scheme is combined to reduce the opportunity of the premature phenomenon. Two fitness functions are given to minimize the zero-pole and amplitude-phase frequency errors for the underlying optimization problems. Some numerical examples are compared to demonstrate the effectiveness and accuracy of this proposed rational approximation method.

关键词： fractional-order calculus rational approximation particle swarm optimization (PSO) tent map.

Effect of background fluctuation on velocity diagnostics by Mach probe

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Plasma Science and Technology 2020年第12期22卷 31-36页

作者： Yunxiao WEI zhe gao Department of Engineering Physics Tsinghua UniversityBeijing 100084People's Republic of China

The effect of background fluctuation on velocity diagnostics is discussed and studied. The kinetic theory of Mach probe(MP) and the theory of BGK mode are combined to evaluate how the measurement of MP is affected by electrostatics fluctuation. It is found that the quantity of speed by the MP model is closer to the effective velocity in the picture of momentum flux rather than the real mean velocity, while, with high fluctuation, the fitting parameter of MP's exponential formula should be corrected.

关键词： velocity diagnostics Mach probe electrostatic fluctuation

Robust Stabilizing Regions of Fractional-order PI~λ Controllers for Fractional-order Systems with Time-delays

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International Journal of Automation and computing 2017年第3期14卷 340-349页

作者： zhe gao Li-Rong Zhai Yan-Dong Liu College of Light Industry Liaoning University College of Information Science and Engineering Northeastern University

This study focuses on a graphical approach to determine the robust stabilizing regions of fractional-order PIλ（proportional integration） controllers for fractional-order systems with time-delays. By D-decomposition technique, the existence conditions and calculating method of the real root boundary（RRB） curves, complex root boundary（CRB） curves and infinite root boundary（IRB）lines are investigated for a given stability degree. The robust stabilizing regions in terms of the RRB curves, CRB curves and IRB lines are identified by the proposed criteria in this paper. Finally, two illustrative examples are given to verify the effectiveness of this graphical approach for different stability degrees.

关键词： Fractional-order systems time-delays PIλ (proportional integration) controllers stabilizing regions stability degree

Study of ZrO_2 nanopowders based stearic acid phase change materials

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Particuology 2010年第4期8卷 394-397页

作者： Desheng Ai Lizan Su zhe gao ,Changsheng Deng Xiaming Dai Beijing Fine Ceramics Lab Institute of Nuclear and New Energy Technology Tsinghua University Haiclian District Beijing 100084 China School of Materials Sci. Er Eng. Seoul National University Seoul 151-742 Republic of Korea

ZrO2 nanopowders based stearic acid phase change materials （PCMS） were prepareo oy mgn-energy milling. The concept of heat capacity factor （HCF） was used to analyze the thermal properties of the materials. The heat storage property of PCMs, containing the same content of stearic acid （23~ by mass） in the starting materials but synthesized by different technical processes, was investigated by using HCE It was found that there were vast influences of different dispersants on the heat capacity. The samples orelaared with chloroform provided the best heat storage ability in all samples tested.

关键词： Heat capacity factor (HCF) High-energy millingPhase change materials (PCMs)

Parameter tuning of fractional-order PDμ controllers based on bacterial foraging -particle swarm optimization algorithm

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Parameter tuning of fractional-order PDμ controllers based ...

Review of preferentially selective lithium extraction from spent lithium batteries: Principle and performance

第25届中国控制与决策会议

作者： DONG Lei SHAN Bo gao zhe LIAO Xiaozhong School of Automation Beijing Institute of Technology Light Industry College Liaoning University

ISBN: (纸本)9781467355339

An improved bacterial foraging-particle swarm optimization algrithm（BF-PSO） is proposed to tune parameters of fractional-order PDμ controllers for fractional-order systems with time-delays. Firstly, parameters are initialized based on the sta- ble regions determined by the analytical method, overcoming the defect of uncertainty stable region by Ziegler-Nichols method. Moreover, the convergence and divergence operator is used to replace the elimination stage of BF-PSO, enhancing the efficiency and accuracy of search. Finally, the simulation results are analyzed to verify the effectiveness of this improved BF-PSO method.

关键词： BF-PSO fractional-order systems stable region PDμ controllers

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Journal of Energy Chemistry 2023年第3期78卷 253-261,I0008页

作者： zhe gao Meiting Huang Liming Yang Yufa Feng Yuan Ding Penghui Shao Xubiao Luo National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization Nanchang Hangkong UniversityNanchang 330063JiangxiChina

Lithium,as the lightest and lowest potential metal,is an ideal "battery metal" and the core strategic metal of the new energy industry *** lithium from spent lithium batteries(LIBs)has become one of the significant approaches to obtaining lithium *** present,the lithium extraction being generally placed at the last step of the spent LIBs recovery process has puzzles such as high acid consumption,low Li recovery purity and low recovery *** lithium extraction at the first step of the recovery process can effectively solve those *** lithium leaching is a non-spontaneous reaction requiring additional energy to achieve,it is found that these methods can be divided into five ways according to the different types of energy driving the reaction occurring:(ⅰ)electric energy driving lithium extraction;(ⅱ) chemical energy driving lithium extraction;(ⅲ) mechanical energy driving lithium extraction;(ⅳ) thermal energy driving lithium extraction;(ⅴ) other energy driving lithium *** the analysis of the principle,reaction process and results of recovering lithium methods can provide a few directions for scholars’ subsequent *** is necessary to speed up the exploration of the principle of these *** is expected that this study could provide a reference for the research on the selective lithium extraction.

关键词： Lithium Spent lithium batteries(LIBs) Recovery efﬁciency Preferentially Selective

A New Hilbert-Type Integral Inequality with Parameters

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Journal of Mathematical Research and Exposition 2011年第3期31卷 467-473页

作者： Xue Mei gao Ming zhe gao Department of Mathematics & Computer Science Normal College of Jishou University Hunan 416000 P. R. China.

In this paper it is shown that a new Hilbert-type integral inequality can be established by introducing two parameters m（m ∈ N） and λ（λ 0）.And the constant factor expressed by the Bernoulli number and π is pro... 详细信息

关键词： Hilbert-type integral inequality hyperbolic cosecant function Bernoulli number weight function best constant.

High densities of magnetic nanoparticles supported on graphene fabricated by atomic layer deposition and their use as efficient synergistic microwave absorbers

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Nano Research 2014年第5期7卷 704-716页

作者： Guizhen wang zhe gao Gengping Wan Shiwei Lin Peng Yang Yong Qin State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 China University of Chinese Academy of Sciences Beijing 100039 China Key Laboratory of Chinese Education Ministry for Tropical Biological Resources Hainan University Haikou 570228 China

An atomic layer deposition （ALD） method has been employed to synthesize Fe3O4/graphene and Ni/graphene composites. The structure and microwave absorbing properties of the as-prepared composites are investigated. The surfaces of graphene are densely covered by Fe3O4 or Ni nanoparticles with a narrow size distribution, and the magnetic nanoparticles are well distributed on each graphene sheet without significant conglomeration or large vacancies. The coated graphene materials exhibit remarkably improved electromagnetic （EM） absorption properties compared to the pristine graphene. The optimal reflection loss （RL） reaches -46.4 dB at 15.6 GHz with a thickness of only 1.4 mm for the Fe3O4/graphene composites obtained by applying 100 cycles of Fe2O3 deposition followed by a hydrogen reduction. The enhanced absorption ability arises from the effective impedance matching, multiple interfacial polarization and increased magnetic loss from the added magnetic constituents. Moreover, compared with other recently reported materials, the composites have a lower filling ratio and smaller coating thickness resulting in significantly increased EM absorption properties. This demonstrates that nanoscale surface modification of magnetic particles on graphene by ALD is a very promising way to design lightweight and high-efficiency microwave absorbers.

关键词： atomic layer deposition(ALD) graphene magnetic nanoparticles microwave absorption

Compact magnetic confinement fusion:Spherical torus and compact torus

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Matter and Radiation at Extremes 2016年第3期1卷 153-162页

作者： zhe gao Department of Engineering Physics Tsinghua University100084China

The spherical torus(ST)and compact torus(CT)are two kinds of alternative magnetic confinement fusion concepts with compact *** ST is actually a sub-category of tokamak with a low aspect ratio;while the CT is a toroidal magnetic configuration with a simply-connected geometry including spheromak and field reversed *** ST and CT have potential advantages for ultimate fusion reactor;while at present they can also provide unique fusion science and technology contributions for mainstream fusion ***,some critical scientific and technology issues should be extensively investigated.

关键词： Spherical torus Compact torus Spheromak Field reversed configuration