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Periodic-phase-diagram similarity method for weak signal detection

International Journal of Mechanical System Dynamics 2021年第2期1卷 248-255页

作者： Ruilan Tian yangkun Zhang Shaopu yang Kai Yuan qiang Xue Quanrong ren State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuangChina Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuangChina

The periodic-phase-diagram similarity method is proposed to identify the frequency of weak harmonic *** key technology is to find a set of optimal coefficients for Duffing system,which leads to the periodic motion under the influence of weak signal and strong *** the phase diagram similarity,the influences of strong noise on the similarity of periodic phase diagram are *** principle of highest similarity of periodic phase diagram with the same frequency is detected by discussing the persistence of similarity of periodic motion phase diagram under the strong noise and the periodic-phase-diagram similarity method is *** weak signals of early fault and strong noise are input into Duffing system to obtain the identified *** stochastic subharmonic Melnikov method is extended to obtain the conditions of the optimal coefficients for the identified *** on the results,the constructed frequency conversion harmonic weak signals are considered to form a datum periodic *** the change of frequency in the datum periodic system,the phase diagram similarity of the two constructed systems can be *** on the periodic-phase-diagram similarity method,the frequency of weak harmonic signals can be identified by the principle of highest similarity of periodic phase diagram with the same *** results of numerical simulation and the early fault diagnosis results of actual bearings verify the feasibility of the periodic-phase-diagram similarity *** accuracy of the detection effect is 97%,and the minimum signal-to-noise ratio is−80.71 dB.

关键词： periodic system signal-to-noise ratio stochastic subharmonic Melnikov method strong noise weak signal

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Theoretical Study on N=126 Shell Evolution

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Communications in Theoretical Physics 2009年第8期52卷 323-328页

作者： SHENG Zong-qiang ren Zhong-Zhou Department of Physics Nanjing University Nanjing 210093 China Center of Theoretical Nuclear Physics National Laboratory of Heavy-Ion Accelerator at Lanzhou Lanzhou 730000 China Joint Center for Particle Nuclear Physics and Cosmology Nanjing 210093 China School of Science Anhui University of Science and Technology Huainan 232001 China

The nuclei around magic number N=126 are investigated in the deformed relativistic mean field (RMF)model with effective interactions *** focus investigations on the N=126 isotonic *** N=126 shellevolution is studied by analyzing the variations of two-neutron (proton) separation energies,quadruple deformations,single particle levels *** good agreement of two-neutron separation energies between experimental data and calculatedvalues is *** RMF theory predicts that the sizes of N=126 shell become smaller and smaller withthe increasing of proton number ***,the N=126 shell exists in our calculated region all *** tothe calculated two-proton separation energies,the RMF theory suggests ^(220)Pu is a two-proton drip-line nucleus in theN=126 isotonic chain.

关键词： shell evolution magic number N = 126 relativistic mean field theory

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Theoretical Study on Alpha-Decay Chains of 294 117 117 and 293 176 117

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Communications in Theoretical Physics 2011年第3期55卷 495-500页

作者： SHENG Zong-qiang ren Zhong-Zhou School of Physics Nanjing University Nanjing 210093 China Center of Theoretical Nuclear Physics National Laboratory of Heavy-ion Accelerator at Lanzhou Lanzhou 730000China Kavli Institute for Theoretical Physics China Beijing 100190 China

The newly synthesized element 117 and its alpha-decay chains are systematically investigated in the framework of the relativistic mean field theory with parameter sets NL-Z2 and TMA. The ground-state properties of the superheavy nuclei on the alpha-decay chains of 294 117 and 293 117 are calculated. The experimental alpha-decay energies and ha Jr-lives of the two alpha-decay chains are reasonably reproduced by the model The detailed discussions on the binding energies, alpha-decay energies, half-lives, quadrupole deformations, potential energy curves, and single particle levels of the two alpha-decay chains are made.

关键词： superheavy nucleus relativistic mean field theory binding energy alpha-decay energy

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A class of generalized odd HamUtonian Lie superalgebras

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Frontiers of Mathematics in China 2014年第5期9卷 1105-1129页

作者： Li ren qiang MU Yongzheng ZHANG School of Mathematics Sichuan University Chengdu 610064 China School of Mathematical Sciences Harbin Normal University Harbin 150025 China School of Mathematics and Statistics Northeast Normal University Changchun 130024 China

We study class of finite-dimensional Cantan-type Lie superalgebras HO（m） over a field of prime characteristic, which can be regarded as extensions of odd Hamiltonian superalgebra HO. And we also determine the deriva... 详细信息

关键词： Derivation superalgebra modular Lie superalgebra Lie superalgebra of Cartan type

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Silicon carbide waste as a source of mixture materials for cement mortar

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Frontiers of Environmental Science & Engineering 2017年第5期11卷 47-54页

作者： Zhengwu Jiang qiang ren Haoxin Li Qing Chen Key Laboratory of Advanced Civil Engineering Materials Ministry of Education Tongji University Shanghai 201804 China

This paper presents an investigation of the feasibility of recycling silicon carbide waste （SCW） as a source of mixture materials in the production of cement mortar. Mortars with SCW were prepared by replacing different amounts of cement with SCW, and the properties of the resulting mortars, such as the fluidity, strength and shrinkage, were studied in this work. Thermogravimetry-differential scanning calorimet;＇y and scanning electron microscopy were employed to understand the reasons for the property changes of the mortars. The results indicate that SCW decreases the initial and l-h fluidity of fresh mortar but improves the loss of fluidity. The mortar with SCW exhibits a lower strength at 3 d and7 d but a higher strength at 28 d and 56 d compared to the control. The shrinkage rate of cement mortar with SCW shows an obvious decrease as the replacement ratio increases. In addition, the content of calcium hydroxide in hardened paste also shows that SCW has some impact on the hydration of the cement-SCW system. The microstructures of the hardened paste also show evidence for a later strength change of mortar containing SCW. This work provides a strategic reference for possibly applying SCW as a mixture material in the production of cement mortar.

关键词： Silicon carbide waste Cement mortar Fluidity Strength Shrinkage

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Biological Stimuli-responsive Polymer Systems:Design,Construction and Controlled Self-assembly

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Chinese Journal of Polymer Science 2018年第3期36卷 347-365页

作者： Miao-Miao Xu ren-Jie Liu qiang Yan Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China

Biological stimuli-responsive polymers have increasingly attracted attention in recent years because it can satisfy many requirements of applications related with human body while traditional systems do not *** to the importance of this burgeoning field,great efforts have been devoted and,up to now,polymer chemists have made a remarkable success in this prospective research *** this review,we systematically generalize the present state of biological stimuli-responsive polymer *** highlight several representative examples to specify the current problems and look ahead a clear sense of direction in this area.

关键词： Biological stimuli Responsive polymer Controlled self-assembly Biomedicine

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Finite-Time Neural Funnel Control for Motor Servo Systems with Unknown Input Constraint

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Journal of Systems Science & Complexity 2017年第3期30卷 579-594页

作者： CHEN qiang TANG Xiaoqing NAN Yurong ren Xuemei College of Information Engineering Zhejiang University of Technology School of Automation Beijing Institute of Technology

In this paper, a finite-time neural funnel control(FTNFC) scheme is proposed for motor servo systems with unknown input constraint. To deal with the non-smooth input saturation constraint problem, a smooth non-affine function of the control input signal is employed to approximate the saturation constraint, which is further transformed into an affine form according to the mean-value theorem. A fast terminal sliding mode manifold is constructed by using a novel funnel error variable to force the tracking error falling into a prescribe boundary within a finite time. Then, a simple sigmoid neural network is utilized to approximate the unknown system nonlinearity including the *** from the prescribed performance control(PPC), the proposed finite-time neural funnel control avoids using the inverse transformed function in the controller design, and could guarantee the prescribed tracking performance without knowing the saturation bounds in prior. The effectiveness and superior performance of the proposed method are verified by comparative simulation results.

关键词： Funnel control input constraint neural network servo system.

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THREE-DIMENSIONAL NUMERICAL SIMULATION OF WAVE SLAMMING ON AN OPEN STRUCTURE

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Journal of Hydrodynamics 2012年第4期24卷 526-534页

作者： DING Zhao-qiang WANG Guo-yu ren Bing State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

The three-dimensional numerical simulation of wave slamming on an open structure in the splash zone is carried out based upon the Volume Of Fluid （VOF） method. A wave basin is established by solving the continuity equation and the Navier-Stoke equations. The linear wave-maker is placed on the left side of the basin, and the numerical sponge layer and the SRC are placed on the right side of the basin to damp the incident waves. The three-dimensional wave slamming boundary condition is adopted to model waves in contact with and separated from the underside of the structure. The numerical results of wave slamming on a foursquare structure for various parametric cases are verified by the experimental results. Meanwhile, the characteristics of the wave impact forces on the undersides of the rectangular structures with various length-breadth ratios are discussed.

关键词： wave slamming three-dimensional Volume Of Fluid (VOF)

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A Better Zn-Ion Storage Device:Recent Progress for Zn-Ion Hybrid Supercapacitors

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Nano-Micro Letters 2022年第4期14卷 158-206页

作者： Jialun Jin Xiangshun Geng qiang Chen Tian-Ling ren School of Integrated Circuits and Beijing National Research Center for Information Science and Technology(BNRist) Tsinghua UniversityBeijing 100084People’s Republic of China College of Material Science and Engineering Zhejiang University of TechnologyHangzhou 310014People’s Republic of China

As a new generation of Zn-ion storage systems,Zn-ion hybrid supercapacitors(ZHSCs)garner tremendous interests recently from researchers due to the perfect integration of batteries and *** have excellent integration of high energy density and power density,which seamlessly bridges the gap between batteries and supercapacitors,becoming one of the most viable future options for large-scale equipment and portable electronic ***,the currently reported two configurations of ZHSCs and corresponding energy storage mechanisms still lack systematic ***,this review will be prudently organized from the perspectives of design strategies,electrode configurations,energy storage mechanisms,recent advances in electrode materials,electrolyte behaviors and further applications(micro or flexible devices)of *** synthesis processes and electrochemical properties of well-designed Zn anodes,capacitor-type electrodes and novel Zn-ion battery-type cathodes are comprehensively ***,a brief summary and outlook for the further development of ZHSCs are presented as *** review will provide timely access for researchers to the recent works regarding ZHSCs.

关键词： Zn-ion storage systems Zn-ion hybrid supercapacitors Carbon electrodes Zinc anodes Electrolytes

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Influence of lanthanum on inclusions and as-cast microstructures in a low-alloy high-strength steel

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Journal of Iron and Steel Research International 2023年第12期30卷 2471-2481页

作者： Can Liu Ji Zhang qiang ren Li-feng Zhang School of Materials Science and Engineering Yanshan UniversityQinhuangdao066004HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China School of Mechanical Engineering Yanshan UniversityQinhuangdao066004HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing100144China

Advanced high-strength steel ingots with total lanthanum(TLa)contents of 0,15×10^(–6),86×10^(–6)and 360×10^(–6)were prepared through laboratory *** modification of inclusions and the variation of the as-cast microstructure with the content of lanthanum in the high-strength steel were *** result showed that with the increase in the TLa content in the steel from 0 to 360×10^(–6),the modification path of inclusions in the as-cast steel was Al2O_(3)and calcium aluminate→LaAlO_(3)→La_(2)O_(2)S→La_(2)O_(2)S–La2O_(3).The addition of La in the high-strength steel significantly refined the solidification *** the increase in the TLa content in the steel from 0 to 360×10^(–6),the ratio of the equiaxed crystal region in the macrostructure increased from 30.1%to 50.7%,the proportion of the high-angle grain boundary in the microstructure increased from 36.9%to 69.8%,and the area fraction of the acicular ferrite and the bainite increased from 0 to 93.3%.Inclusions of LaAlO_(3),La_(2)O_(2)S and La2O_(3)in the La-containing steel could act as heterogeneous nucleation cores ofα-Fe during the *** the increase in the TLa content in the steel,the number density of inclusions that could act as effective heterogeneous nucleation cores in the steel gradually increased,which enlarged the ratio of the equiaxed crystal region and the proportion of intragranular acicular ferrite,and refined the as-cast microstructure of the high-strength steel.

关键词： Advanced high-strength steel Lanthanum Inclusion Heterogeneous nucleation As-cast microstructure

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