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Test of a model coupling of electromagnetic and gravitational fields by using high-frequency gravitational waves

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Science China(Physics,Mechanics & Astronomy) 2021年第5期64卷 22-27页

作者： Yinhua zou Mengjie Wang 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

Models of the coupling of electromagnetic and gravitational fields have been studied extensively for many years. In this paper,we consider the coupling between the Maxwell field and the Weyl tensor of the gravitational field to study how the wavevector of the electromagnetic wave is affected by a plane gravitational wave. We find that the wavevector depends upon the frequency and direction of polarization of the electromagnetic waves, the parameter that couples the Maxwell field and the Weyl tensor, and the angle between the direction of propagation of the electromagnetic wave and the coordinate axis. The results show that this coupling model can be tested by the detection of high-frequency gravitational waves.

关键词： modified theory gravitational wave wave vector

Reinforcement Learning Based Data Fusion Method for Multi-Sensors

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IEEE/CAA Journal of Automatica Sinica 2020年第6期7卷 1489-1497页

作者： Tongle Zhou Mou Chen Jie zou College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China IEEE Science and Technology on Electron-Optic Control Laboratory Luoyang Institute of Electro-Optical Equipment of AvicLuoyang 471023China

In order to improve detection system robustness and reliability, multi-sensors fusion is used in modern air combat. In this paper, a data fusion method based on reinforcement learning is developed for multi-sensors. Initially, the cubic B-spline interpolation is used to solve time alignment problems of multisource data. Then, the reinforcement learning based data fusion(RLBDF) method is proposed to obtain the fusion results. With the case that the priori knowledge of target is obtained, the fusion accuracy reinforcement is realized by the error between fused value and actual value. Furthermore, the Fisher information is instead used as the reward if the priori knowledge is unable to be obtained. Simulations results verify that the developed method is feasible and effective for the multi-sensors data fusion in air combat.

关键词： Air combat cubic B-spline interpolation data fusion reinforcement learning

Set-Membership Filtering Approach to Dynamic Event-Triggered Fault Estimation for a Class of Nonlinear Time-Varying Complex Networks

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 638-648页

作者： Xiaoting Du Lei zou Maiying Zhong the College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China IEEE the College of Information Science and Technology Donghua UniversityShanghai 201620 the Engineering Research Center of Digitalized Textile and Fashion Technology Ministry of EducationShanghai 201620China

The present study addresses the problem of fault estimation for a specific class of nonlinear time-varying complex networks,utilizing an unknown-input-observer approach within the framework of dynamic event-triggered mechanism(DETM).In order to optimize communication resource utilization,the DETM is employed to determine whether the current measurement data should be transmitted to the estimator or *** guarantee a satisfactory estimation performance for the fault signal,an unknown-input-observer-based estimator is constructed to decouple the estimation error dynamics from the influence of fault *** aim of this paper is to find the suitable estimator parameters under the effects of DETM such that both the state estimates and fault estimates are confined within two sets of closed ellipsoid *** techniques of recursive matrix inequality are applied to derive sufficient conditions for the existence of the desired estimator,ensuring that the specified performance requirements are met under certain ***,the estimator gains are derived by minimizing the ellipsoid domain in the sense of trace and a recursive estimator parameter design algorithm is then ***,a numerical example is conducted to demonstrate the effectiveness of the designed estimator.

关键词： Dynamic event-triggered mechanism(DETM) fault estimation nonlinear time-varying complex networks set-member-ship filtering unknown input observer

Optimization for sound insulation of a sandwich plate with a corrugation and auxetic honeycomb hybrid core

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1595-1612页

作者： Fenglian LI Yiping WANG Yuxing zou School of Mechanical and Electrical Engineering Beijing Information Science and Technology UniversityBeijing 100192China

A sandwich plate with a corrugation and auxetic honeycomb hybrid core is constructed,and its sound insulation and optimization are ***,the motion governing equation of the sandwich plate is established by the third-order shear deformation theory(TSDT),and then combined with the fluid-structure coupling conditions,and the sound insulation is *** theoretical results are validated by COMSOL simulation results,and the effects of the structural parameter on the sound insulation are ***,the standard genetic algorithm is adopted to optimize the sound insulation of the sandwich plate.

关键词： optimization sound insulation hybrid core layer genetic algorithm

Connectivity-maintaining Consensus of Multi-agent Systems With Communication Management Based on Predictive Control Strategy

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IEEE/CAA Journal of Automatica Sinica 2023年第3期10卷 700-710页

作者： Jie Wang Shaoyuan Li Yuanyuan zou Key Laboratory of System Control and Information Processing Shanghai Jiao Tong UniversityShanghai 200240China IEEE

This paper studies the connectivity-maintaining consensus of multi-agent *** the impact of the sensing ranges of agents for connectivity and communication energy consumption,a novel communication management strategy is proposed for multi-agent systems so that the connectivity of the system can be maintained and the communication energy can be *** this paper,communication management means a strategy about how the sensing ranges of agents are adjusted in the process of reaching *** proposed communication management in this paper is not coupled with controller but only imposes a constraint for controller,so there is more freedom to develop an appropriate control strategy for achieving *** the multi-agent systems with this novel communication management,a predictive control based strategy is developed for achieving *** results indicate the effectiveness and advantages of our scheme.

关键词： Consensus energy-saving multi-agent system predictive control

Recent advances in designing ZnIn_(2)S_(4)-based heterostructured photocatalysts for hydrogen evolution

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Journal of Materials Science & Technology 2023年第8期139卷 167-188页

作者： Chao Liu Qinfang Zhang Zhigang zou School of Materials Science and Engineering Yancheng Institute of TechnologyYancheng 224051China Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province Yancheng Institute of TechnologyYancheng 224051China Eco-Materials and Renewable Energy Research Centre(ERERC) School of PhysicsNanjing UniversityNanjing 210093China

Water and solar energy are inexhaustible on Earth,and thus hydrogen evolution through photocatalytic water splitting taking sunlight as the input energy is an ideal green energy generation *** a typical visible-light-responsive photocatalyst,ZnIn_(2)S_(4)attracted worldwide research attention because of its many advantages for photocatalytic hydrogen evolution(PHE),such as layered structure,simple syn-theses,structural stability,environmental friendliness,and suitable electronic band *** recent years,constructing ZnIn_(2)S_(4)-based heterostructured photocatalysts has become a research focus for their significantly improved spatial charge carrier separation efficiency and PHE *** to the charge carrier transfer/separation mechanisms,heterostructured ZnIn_(2)S_(4)-based photocatalysts are divided into five categories,conventional heterojunctions(type-I and type-II),p-n heterojunction,Z-scheme het-erojunction,S-scheme(or Step-scheme)heterojunction,and co-catalyst deposition based heterojunction *** article reviews the recent advances in ZnIn_(2)S_(4)-based heterostructured photocatalysts for ***,the central part of this review introduced various ZnIn_(2)S_(4)-based heterojunctions and their PHE ***,apart from common half-reaction of water-splitting,we expressly introduced overall water splitting,dual-functional and photothermal effect-assisted PHE ***,we briefly presented some identification methods for confirming heterojunction ***,the current states,challenges and perspectives of ZnIn_(2)S_(4)-based heterostructured photocatalysts for PHE are also *** review aims to explore the advantages of diverse ZnIn_(2)S_(4)-based heterostructures,and can provide an insight into designing high-efficiency heterostructured photocatalysts for PHE application.

关键词： Photocatalysis Photocatalytic hydrogen evolution ZnIn_(2)S_(4) Heterojunction Charge transfer mechanism S-scheme heterojunction

A refined design method for precoolers with consideration of multi-parameter variations based on low-dimensional analysis

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Chinese Journal of Aeronautics 2022年第3期35卷 329-344页

作者： Hui LI Zhengping zou Yumin LIU National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Energy&Power Engineering Beihang University Beijing 100083China Advanced Jet Propulsion Creativity Center AEACBeijing 101304China Research Institute of Aero-Engine Beihang University Beijing 100083China International School Beihang University Beijing 100083China

The precooler is a distinctive component of precooled air-breathing engines but constitutes a challenge to conventional thermal design *** latter are based upon assumptions that often reveal to be limited for precooler *** this paper,a refined design method considering the variations of fluid thermophysical properties,flow area and thermal parameters distortion,was proposed to remediate their ***,the precooler was discretized into a fixed number of sub-microtubes based on a new discretization ***,in-house one-dimensional(1D)and two-dimensional(2D)segmented models were established for rapid thermal design and precooler rating with non-uniform airflow,*** heat transfer experimental studies of supercritical hydrocarbon fuel were performed to verify the Jackson correlation for precooler design and the in-house models were validated against the reported data from open *** this basis,the proposed method was employed for the design analysis of hydrocarbon fuel precoolers for precooled-Turbine Based Combined Cycle(TBCC)*** results show that the local performance of precoolers is intrinsically impacted by the aforementioned three *** the case study,the local heat transfer performance is drastically affected by coolant flow *** the circumferential temperature distortion of airflow is weakened by heat *** consideration of additional parameter variations,this novel method improves design accuracy and shortens the design time.

关键词： Compact heat exchangers Heat exchanger design Low-dimensional segmented model Non-uniform inflow Precooled engine Thermophysical properties variation

Fabrication of onion-like carbon from nanodiamond by annealing

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Science China(Technological Sciences) 2009年第12期52卷 3683-3689页

作者： Qin zou MingZhi Wang YanGuo Li YuCheng Zhao LiangHua zou State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 China

Onion-like carbon (OLC) was synthesized by annealing nanodiamond in low vacuum of 1 Pa and at annealing temperatures from 500°C to 1400°C. The high-resolution transmission electron microscope (HRTEM) images, X-ray diffraction (XRD) and Raman spectrum of the OLC showed that there was no OLC when the annealing temperature was lower than 900°C. Moreover, the fragment amorphous carbon existed on the surfaces of the nanodiamond particles. At the annealing temperature of 900°C, the OLC particles began appearing and the size of the OLC particles was smaller than 5 nm. When the annealing temperature was increased from 900°C to 1400°C, the nanodiamond was transformed into OLC gradually. At the annealing temperature of 1400°C, all the nanodiamond particles were transformed into OLC completely. The OLC exhibited similarity to the original nanodiamond particles in shape. A mechanism for the OLC synthesis by annealing was provided. The graphitization started at the surfaces of the nanodiamond particles. The formation process of the OLC includes formation of graphite fragments, connection and curvature of graphite sheets between diamond (111) planes and closure of the graphite layers.

关键词： onion-like carbon(OLC) nanodiamond annealing fabrication

A preliminary study of polymer inclusion membrane for lutetium(Ⅲ)separation and membrane regeneration

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Journal of Rare Earths 2021年第10期39卷 1256-1263,I0004页

作者： Siyan Huang Ji Chen Dan zou State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China

This paper reports on the selective transport of Lu(Ⅲ)from La(III)and Sm(III)through a polymer inclusion membrane(PIM)composed of 40 wt%di(2-ethylhexyl)phosphinic acid(P227)and 60 wt%poly(vinylidene fluoride)(PVDF).Basically,the changes in surface morphology,thickness and water contact angle of this PVDF-based PIM containing P227(P227@PVDF PIM)with different polymer concentrations were *** solvent extraction experiments,it is found that Lu(Ⅲ)can be selectively extracted from La(Ⅲ)and Sm(Ⅲ)at pH 1.5 in hydrochloric acid *** to this result,P227@PVDF PIM was used to selectively transport Lu(Ⅲ)from hydrochloric acid feed solution containing similar concentration of La(Ⅲ)and Sm(Ⅲ).The recovery factor of Lu(III)is 91% after 36 h,and about 5%of Sm(Ⅲ)was also transported through the *** concentration of La(III)in the feed solution and the stripping solution does not ***,to overcome the ubiquitous decline of transport efficiency caused by the loss of carrier or the damage of membrane structure after long-term use of PIMs,a process for regenerating PIMs was first proposed and *** comparison of the regenerated PIM with the normal PIM,there is almost no difference in the SEM image,ATR-FTIR spectrum and Lu(III)transport *** is expected that P227@PVDF PIMs have the potential to be applied to the grouped separation of rare earth elements(REEs),and this study also can be as an inspiration for the further study on the PIMs regeneration process.

关键词： Polymer inclusion membrane(PIM) Di(2-ethylhexyl)phosphinic acid(P227) Lutetium Rare earths Separation