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Applied Mathematics and Mechanics(English Edition) 2024年第10期45卷 1705-1716页

作者： Jiangcheng CAI Mingxi deng college of Aerospace Engineering Chongqing University

Acoustic nonlinearity holds potential as a method for assessing material stress. Analogous to the acoustoelastic effect, where the velocity of elastic waves is influenced by third-order elastic constants, the propagation of nonlinear acoustic waves in pre-stressed materials would be influenced by higher-order elastic constants. Despite this,there has been a notable absence of research exploring this phenomenon. Consequently,this paper aims to establish a theoretical framework for governing the propagation of nonlinear acoustic waves in pre-stressed materials. It delves into the impact of pre-stress on higher-order material parameters, and specifically examines the propagation of onedimensional acoustic waves within the contexts of the uniaxial stress and the biaxial stress. This paper establishes a theoretical foundation for exploring the application of nonlinear ultrasonic techniques to measure pre-stress in materials.

关键词： 74J30 acoustoelastic effect higherorder elastic constant nonlinear elastic wave O343 pre-stress medium

Non-intrusive Load Monitoring Based on Graph Total Variation for Residential Appliances

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 947-957页

作者： Xiaoyang Ma Diwen Zheng Xiaoyong deng Ying Wang Dawei deng Wei Li the college of Electrical Engineering Sichuan UniversityChengdu 610065China State Grid Chongqing Electric Power Company Chongqing 400014China State Grid Sichuan Electric Power Company Chengdu 610095China State Grid Hubei Electric Power Company Limited Research Institute Wuhan 430077China

Non-intrusive load monitoring is a technique for monitoring the operating conditions of electrical appliances by collecting the aggregated electrical information at the household power *** several studies on the mining of unique load characteristics,few studies have extensively considered the high computational burden and sample *** on lowfrequency sampling data,a non-intrusive load monitoring algorithm utilizing the graph total variation(GTV)is proposed in this *** algorithm can effectively depict the load state without the need for prior ***,the combined Kmeans clustering algorithm and graph signals are used to build concise and accurate graph structures as load *** GTV representing the internal structure of the graph signal is introduced as the optimization model and solved using the augmented Lagrangian iterative *** introduction of the difference operator reduces the computing cost and addresses the inaccurate reconstruction of the graph *** low-frequency sampling data,the algorithm only requires a little prior data and no training,thereby reducing the computing *** conducted using the reference energy disaggregation dataset and almanac of minutely power dataset demonstrated the stable superiority of the algorithm and its low computational burden.

关键词： Non-intrusive load monitoring graph total variation augmented Lagrangian function smart grid

INVARIANTS-PRESERVING DU fORT-fRANKEL SCHEMES AND THEIR ANALYSES fOR NONLINEAR SCHRÖDINGER EQUATIONS WITH WAVE OPERATOR

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Journal of Computational Mathematics 2024年第3期42卷 814-850页

作者： Dingwen deng Zhijun Li college of Mathematics and Information Science Nanchang Hangkong UniversityNanchang 330063China

Du fort-frankel finite difference method(fDM)was firstly proposed for linear diffusion equations with periodic boundary conditions by Du fort and frankel in *** is an explicit and unconditionally von Neumann stable ***,there has been no research work on numerical solutions of nonlinear Schrödinger equations with wave operator by using Du fort-frankel-type finite difference methods(fDMs).In this study,a class of invariants-preserving Du fort-frankel-type fDMs are firstly proposed for one-dimensional(1D)and two-dimensional(2D)nonlinear Schrödinger equations with wave *** using the discrete energy method,it is shown that their solutions possess the discrete energy and mass conservative laws,and conditionally converge to exact solutions with an order of for ofο(T^(2)+h_(x)^(2)+(T/h_(x))^(2))1D problem and an order ofο(T^(2)+h_(x)^(2)+h_(Y)^(2)+(T/h_(X))^(2)+(T/h_(y))^(2))for 2D problem in ***,τdenotes time-step size,while,hx and hy represent spatial meshsizes in x-and y-directions,***,by introducing a stabilized term,a type of stabilized invariants-preserving Du fort-frankel-type fDMs are *** not only preserve the discrete energies and masses,but also own much better stability than original ***,numerical results demonstrate the theoretical analyses.

关键词： Nonlinear Schrodinger equations with wave operator Du fort-frankel finite difference methods Discrete energy and mass conservative laws Numerical convergence

Performance of physical-informed neural network (PINN) for the key parameter inference in Langmuir turbulence parameterization scheme

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Acta Oceanologica Sinica 2024年第5期43卷 121-132页

作者： fangrui Xiu Zengan deng School of marine Science and Technology Tianjin UniversityTianjin 300072China

The Stokes production coefficient(E_(6))constitutes a critical parameter within the Mellor-Yamada type(MY-type)Langmuir turbulence(LT)parameterization schemes,significantly affecting the simulation of turbulent kinetic energy,turbulent length scale,and vertical diffusivity coefficient for turbulent kinetic energy in the upper ***,the accurate determination of its value remains a pressing scientific *** study adopted an innovative approach by leveraging deep learning technology to address this challenge of inferring the E_(6).Through the integration of the information of the turbulent length scale equation into a physical-informed neural network(PINN),we achieved an accurate and physically meaningful inference of E_(6).Multiple cases were examined to assess the feasibility of PINN in this task,revealing that under optimal settings,the average mean squared error of the E_(6) inference was only 0.01,attesting to the effectiveness of *** optimal hyperparameter combination was identified using the Tanh activation function,along with a spatiotemporal sampling interval of 1 s and 0.1 *** resulted in a substantial reduction in the average bias of the E_(6) inference,ranging from O(10^(1))to O(10^(2))times compared with other *** study underscores the potential application of PINN in intricate marine environments,offering a novel and efficient method for optimizing MY-type LT parameterization schemes.

关键词： Langmuir turbulence physical-informed neural network parameter inference

A Data Intrusion Tolerance Model Based on an Improved Evolutionary Game Theory for the Energy Internet

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Computers, Materials & Continua 2024年第6期79卷 3679-3697页

作者： Song deng Yiming Yuan Institute of Advanced Technology Nanjing University of Posts and TelecommunicationsNanjing210003China college of Automation Nanjing University of Posts and TelecommunicationsNanjing210003China

Malicious attacks against data are unavoidable in the interconnected,open and shared Energy Internet(EI),Intrusion tolerant techniques are critical to the data security of *** intrusion tolerant techniques suffered from problems such as low adaptability,policy lag,and difficulty in determining the degree of *** address these issues,we propose a novel adaptive intrusion tolerance model based on game theory that enjoys two-fold ideas:(1)it constructs an improved replica of the intrusion tolerance model of the dynamic equation evolution game to induce incentive weights;and (2)it combines a tournament competition model with incentive weights to obtain optimal strategies for each stage of the game *** experiments are conducted in the IEEE 39-bus system,whose results demonstrate the feasibility of the incentive weights,confirm the proposed strategy strengthens the system’s ability to tolerate aggression,and improves the dynamic adaptability and response efficiency of the aggression-tolerant system in the case of limited resources.

关键词： Energy Internet Intrusion tolerance game theory racial competition adaptive intrusion response

Energy flux and waveform of gravitational wave generated by coalescing slow-spinning binary system in effective one-body theory

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 73-83页

作者： Weike deng Sheng Long Jiliang Jing Department of Physics Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Educationand Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China

We extend our research on the energy flux and waveform characteristics of gravitational waves generated by merging nonspinning binary black holes through self-consistent effective one-body theory to include binary systems with slowly spinning black ***,we decompose the equation for the null tetrad component of the gravitationally perturbed Weyl tensorψ_4~B into radial and angular parts,leveraging the second-order approximation of the rotation parameter ***,we derive an analytical solution for the radial equation and observe that our results are contingent upon the parameters a_(2),a_(3),and a,which represent the second-and third-order correction parameters,***,we calculate the energy flux,the radiation-reaction force and the waveform for the“plus”and“cross”modes of the gravitational waves generated by merging slowly spinning binary black holes.

关键词： post-Minkowskian approximation effective-one-body theory gravitational waveform template

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In situ sulfur-doped mesoporous tungsten oxides for gas sensing toward benzene series

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Chinese Chemical Letters 2024年第7期35卷 502-507页

作者： Yu deng Yan Liu Yonghui deng Jinsheng Cheng Yidong Zou Wei Luo State Key Laboratory for Modification of Chemical fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China Department of Chemistry State Key Laboratory of Molecular Engineering of PolymersShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsiChEMFudan UniversityShanghai 200433China Department of Polymeric Materials School of Materials Science and EngineeringTongji UniversityShanghai 201804China Henry-fork School of food Sciences Shaoguan UniversityShaoguan 512005China State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

Benzene series as highly toxic gases have inevitably entered human life and produce great threat to human health and ecological environment,and thus it is distinctly meaningful to monitor benzene series with quickly,real-time and efficient ***,novel sulfur-doped mesoporous WO_(3)materials were synthesized via classical in-situ solvent evaporation induced co-assembly strategy combined with doping engineering,which possessed highly crystallized frameworks,high specific surface area(40.9–63.8 m^(2)/g)and uniform pore size(~18 nm).Benefitting from abundant oxygen vacancy and defects via S-doping,the tailored mesoporous S/m WO_(3)exhibited excellent benzene sensing performance,including high sensitivity(50 ppm vs.48),low detection limit(ca.500 ppb),outstanding selectivity and favorable *** addition,the reduction of band gap resulted from S-doping promotes the carrier migration in the sensing materials and the reaction at the gas–solid sensing *** provides brand-new approach to design sensitive materials with multiple reaction sites.

关键词： Mesoporous materials Benzene series Tungsten oxides Sulfur doping Gas sensor

Energy flux and waveforms by coalescing spinless binary system in effective one-body theory

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 58-68页

作者： Sheng Long Weike deng Jiliang Jing Department of Physics Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of EducationSynergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China

We present a study on the energy radiation rate and waveforms of the gravitational wave generated by coalescing spinless binary systems up to the third post-Minkowskian approximation in the effective one-body *** derive an analytical expansion of the null tetrad components of the gravitational perturbed Weyl tensorΨ4in the effective spacetime,we utilize the method proposed by Sasaki et *** this investigation,we discover more general integral formulas that provide a theoretical framework for computing the results in any ***,we successfully compute the energy radiation rate and waveforms of the gravitational wave,which include the results of the Schwarzschild case and the correction terms resulting from the dimensionless parameters a2and a3in the effective metric.

关键词： post-Minkowskian approximation effective one-body theory gravitational waveform template

Synthesis of multifunctional additives for solid propellants:Structure,properties and mechanism

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Defence Technology（防务技术） 2024年第3期33卷 308-316页

作者： Pingan Zhang Lina Sun Jianmin Yuan Jianru deng college of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082PR China college of Material Science and Engineering Hunan UniversityChangsha 410082PR China Hu Bei Sanjiang Aerospace Jianghe Chemical Technology Co. LtdYichang 444200PR China

To simplify the composite propellant formulation and address the current issue of the single-functionality present in existing additives,the multi-cyano,amine-based polybutadiene(AEHTPB-CN)was prepared based on AEHTPB by adopting appropriate synthesis *** replacing 10% of HTPB binder in the propellant formulation,it can effectively enhance the interfacial bond strength between the propellant binder matrix and solid fillers(AP(ammonium perchlorate)and RDX(cyclotrimethylene-trinitramine)),the mechanical properties of the HTPB/AP/RDX/Al propellant were superior to blank control propellant with an improvement of 35.4% in tensile strength,62.0% enhancement in elongation at break,and reduce the propellant burn rate by 10.7% with any energy *** function mechanism of AEHTPB-CN was systematically elucidated through experiments and computer simulation *** results show that the tertiary amine group in AEHTPB-CN can react with AP to form ammonium ionic bonds,and the hydroxyl and cyano groups can form hydrogen bonding interactions with AP,which enables AEHTPB-CN to be firmly adsorbed on the AP surface through chemical and physical *** RDX,the interfacial bonding effect of AEHTPB-CN is attributed to their ability to form C-H···N≡C weak hydrogen bonding interaction between the cyano group and RDX methylene group.

关键词： Hydroxyl-terminated polybutadiene(HTPB) HTPB propellant Chemical modification Bonding agent Mechanism