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Journal of Systems Engineering and Electronics 2024年第1期35卷 24-30页

作者： TIAN Jing zhang wei School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Electromagnetic Space Security Chengdu 610036China

In engineering application,there is only one adaptive weights estimated by most of traditional early warning radars for adaptive interference suppression in a pulse reputation interval(PRI).Therefore,if the training samples used to calculate the weight vector does not contain the jamming,then the jamming cannot be removed by adaptive spatial *** the weight vector is constantly updated in the range dimension,the training data may contain target echo signals,resulting in signal cancellation *** cope with the situation that the training samples are contaminated by target signal,an iterative training sample selection method based on non-homogeneous detector(NHD)is proposed in this paper for updating the weight vector in entire range *** principle is presented,and the validity is proven by simulation results.

关键词： adaptive radar beamforming training sample selection non-homogeneous detector electronic jamming jamming suppression

Inter-well internal resonance analysis of rectangular asymmetric cross-ply bistable composite laminated cantilever shell under transverse foundation excitation

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1353-1373页

作者： Lele REN wei zhang Yufei zhang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Department of Mechanics Guangxi University Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures College of Mechanical Engineering Beijing University of Technology

The chaotic dynamic snap-through and complex nonlinear vibrations are investigated in a rectangular asymmetric cross-ply bistable composite laminated cantilever shell, in cases of 1 : 2 inter-well internal resonance and primary resonance. The transverse foundation excitation is applied to the fixed end of the structure, and the other end is in a free state. The first-order approximate multiple scales method is employed to perform the perturbation analysis on the dimensionless two-degree-of-freedom ordinary differential motion control equation. The four-dimensional averaged equations are derived in both polar and rectangular coordinate forms. Deriving from the obtained frequency-amplitude and force-amplitude response curves, a detailed analysis is conducted to examine the impacts of excitation amplitude, damping coefficient, and tuning parameter on the nonlinear internal resonance characteristics of the system. The nonlinear softening characteristic is exhibited in the upper stable-state, while the lower stable-state demonstrates the softening and linearity characteristics. Numerical simulation is carried out using the fourth-order Runge-Kutta method, and a series of nonlinear response curves are plotted. Increasing the excitation amplitude further elucidates the global bifurcation and chaotic dynamic snap-through characteristics of the bistable cantilever shell.

关键词： 74K10 bistable composite laminated cantilever shell chaotic dynamic snap-through complex nonlinear vibration inter-well internal resonance O322 primary resonance

State of the art of lightweight aggregates used in lightweight refractories for working lining of high-temperature furnaces

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Journal of Iron and Steel Research(International) 2024年第6期31卷 1320-1343页

作者： wei zhang Wen-yong Dai Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina Research and Development Department AGC Plibrico(Dalian)Industries Inc.Dalian 116600LiaoningChina

Lightweight refractories for the working lining of high-temperature furnaces play an important role in the smelting of advanced steels and *** prepare lightweight refractories for the working lining of high-temperature furnaces,the synthesis of lightweight aggregates is the ***,the research on the synthesis of lightweight aggregates with high service temperature,low thermal conductivity,high strength,and good slag resistance has received widespread *** available literature on the synthesis of lightweight aggregates was summarized,including corundum,mullite,mullite-corundum,spinel,corundum-spinel,cordierite,cordierite-mullite,calcium hexaluminate,corundum-calcium hexaluminate,bauxite,magnesia,magnesia-based,and forsterite-based ***,the future development trend of lightweight aggregates was proposed.

关键词： Lightweight aggregate Lightweight refractory Working lining Apparent porosity Closed porosity Thermal conductivity Pore-forming approach

Experimentally Ruling Out Joint Reality Based on Locality with Device-Independent Steering

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Chinese Physics Letters 2024年第1期41卷 1-5页

作者： Shuaining zhang Xiang zhang Zhiyue Zheng wei zhang Beijing Academy of Quantum Information Sciences Beijing 100193China Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices Renmin University of ChinaBeijing 100872China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China

As an essential concept to understand the world,whether the real values(or physical realities)of observables are suitable to physical systems beyond the classic has been debated for many *** standard nogo results based on Bell inequalities have ruled out the joint reality of incompatible quantum observables,the possibility of giving simple yet strong arguments to rule out joint reality in any physical system(not necessarily quantum)with weaker assumptions and less observables has been explored and proposed ***,we perform a device-independent experiment on a two-qubit superconducting system to show that the joint reality of two observables is incompatible with locality under the weaker assumption of the reality of observables in a single space-time region(or single qubit).Our results clearly show the violation of certain inequalities derived from both linear and nonlinear *** addition,we study the robustness of the linear and nonlinear criterion against the effect of systematic *** demonstration opens up the possibility of delineating classical and non-classical boundaries with simpler nontrivial quantum system.

关键词： observable quantum system

Snap-through behaviors and nonlinear vibrations of a bistable composite laminated cantilever shell:an experimental and numerical study

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 779-794页

作者： Lele REN wei zhang Ting DONG Yufei zhang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Department of Mechanics Guangxi UniversityNanning 530004China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures College of Mechanical EngineeringBeijing University of TechnologyBeijing 100124China School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

The snap-through behaviors and nonlinear vibrations are investigated for a bistable composite laminated cantilever shell subjected to transversal foundation excitation based on experimental and theoretical *** improved experimental specimen is designed in order to satisfy the cantilever support boundary condition,which is composed of an asymmetric region and a symmetric *** symmetric region of the experimental specimen is entirely clamped,which is rigidly connected to an electromagnetic shaker,while the asymmetric region remains free of *** motion paths are realized for the bistable cantilever shell by changing the input signal levels of the electromagnetic shaker,and the displacement responses of the shell are collected by the laser displacement *** numerical simulation is conducted based on the established theoretical model of the bistable composite laminated cantilever shell,and an off-axis three-dimensional dynamic snap-through domain is *** numerical solutions are in good agreement with the experimental *** nonlinear stiffness characteristics,dynamic snap-through domain,and chaos and bifurcation behaviors of the shell are quantitatively *** to the asymmetry of the boundary condition and the shell,the upper stable-state of the shell exhibits an obvious soft spring stiffness characteristic,and the lower stable-state shows a linear stiffness characteristic of the shell.

关键词： bistable composite laminated cantilever shell snap-through behavior nonlinear vibration nonlinear stiffness characteristic chaos and bifurcation

Coupled simulation of fluid-particle interaction for large complex granules:A resolved CFD-DEM method for modelling the airflow in a vertical fixed bed of irregular sinter particles

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Particuology 2024年第7期90卷 292-306页

作者： Chengzhi Li Yu zhang Jiahe Shen wei zhang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081China Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081China School of Transportation and Logistics Engineering Wuhan University of TechnologyWuhan 430063China Centre for Bulk Solids and Particulate Technologies The University of NewcastleCallaghan NSW 2308Australia

A resolved CFD-DEM method is proposed to simulate the fluid-particle interaction for large complex *** airflow in a vertical sinter fixed bed is numerically studied using this *** multi-sphere clumped method is used to create irregular sinter particles in *** immersed boundary method and dynamic cell refinement are applied to describe the fluid flow around particles with higher resolution,by which the fluid-particle interaction can be simulated more *** simulation results presented the packing voidage distributions and the airflow fields in the sinter beds of different single and mixed particle size *** bed pressure drops were simulated and the results were compared with the corresponding experimental *** good agreement indicated that the proposed resolved CFD-DEM method is an effective tool to model the fluid-particle interaction for irregular large granules in the gas-solid multi-phase systems.

关键词： Resolved CFD-DEM method Irregular sinter particles Multi-sphere clumped method Immersed boundary method Dynamic cell refinement

Improving hydrogen storage thermodynamics and kinetics of Ce-Mg-Ni-based alloy by mechanical milling with TiF_(3)

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Journal of Magnesium and Alloys 2024年第4期12卷 1593-1607页

作者： Hongwei Shang wei zhang Xin wei Yaqin Li Zeming Yuan Jun Li Yanghuan zhang School of Mechanical and Electrical Engineering Chuzhou UniversityChuzhou 239000China Department of Functional Material Research Central Iron and Steel Research InstituteNo.76 Xueyuannan RoadHaidian DistrictBeijing 100081China Key Laboratory of Integrated Exploitation of Bayan-Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010China China Rare Earth New Material(weishan)Co. Ltd.Jining 277600China

Mg-based hydrides are too stable and the kinetics of hydrogen absorption and desorption is not *** efficient way to improve these shortcomings is to employ reactive ball milling to synthesize the nanocomposite materials of Mg and *** this experiment,TiF_(3)was selected as an additive,and the mechanical milling method was employed to prepare the experimental *** alloys used in this experiment were the as-cast Ce_(5)Mg_(85)Ni_(10),as-milled Ce_(5)Mg_(85)Ni_(10)and Ce_(5)Mg_(85)Ni_(10)+3 wt.%*** phase transformation,structural evolution,isothermal and non-isothermal hydrogenation and dehydrogenation performances of the alloys were inspected by XRD,SEM,TEM,Sievert apparatus,DSC and *** revealed that nanocrystalline appeared in the as-milled *** with the as-cast alloy,ball milling made the particle dimension and grain size decrease dramatically and the defect density increase *** addition of TiF_(3)made the surface of ball milling alloy particles markedly coarser and more *** milling and adding TiF_(3)distinctly improved the activation and kinetics of the ***,ball milling along with TiF_(3)can decrease the onset dehydrogenation temperature of Mg-based hydrides and slightly ameliorate their thermodynamics.

关键词： Mg-based hydrides TiF_(3) Ball milling Thermodynamics Kinetics

Characterization of Fe-containing particles in Chengdu,southwest China,using single-particle aerosol mass spectrometry

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Journal of Environmental Sciences 2024年第2期136卷 110-120页

作者： Renjiang He Junke zhang Luyao Chen wei zhang Yingwei Xi School of Public Health Southwest Medical UniversityLuzhou 646000China Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China Sichuan Environmental Monitoring Center Chengdu 610074China

Single-particle aerosol mass spectrometry was used to study the characteristics of Fecontaining particles during winter in Chengdu,southwest *** mass concentrations of PM_(2.5)and PM_(10)during the study period were 64±38 and 89±49μg/m~3,respectively,and NO_(2)and particulate matter were high compared with most other regions of *** Fecontaining particles were divided into seven categories with different mass spectra,sources and aging *** highest contribution was from Fe mixed with carbonaceous components(Fe-C,23.1%)*** was more mixed with sulfate than nitrate and therefore the contribution of Fe mixed with sulfate(Fe-S,20.7%)particles was higher than that of Fe mixed with nitrate(Fe-N,12.5%)*** contributions from Fe-containing particles related to primary combustion were high in the small particle size range,whereas aged Fecontaining particles and dust-related particles were mostly found in the coarse particle size *** air masses mainly originated from the west and east of Chengdu,and the corresponding PM_(2.5)concentrations were 79±36 and 55±36μg/m~3,*** west and east air masses showed stronger contributions of Fe-containing particles related to biomass burning(Fe-B)and fossil fuel combustion(Fe-C and Fe-S)particles,*** southwest area contributed the most Fe-containing *** assessments of the effects of Fe-containing particles during heavy pollution period should pay more attention to Fe-C and Fe-S ***-reduction of Fe-containing particles should consider both local emissions and short-distance transmission from the surrounding areas.

关键词： Fe-containing particles Particle composition Potential source areas Evolution Chengdu

Potential and progress of studying mountain biodiversity by means of butterfly genetics and genomics

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Journal of Genetics and Genomics 2024年第3期51卷 292-301页

作者： Shuting Wang Marco Girardello wei zhang State Key Laboratory of Protein and Plant Gene Research School of Life SciencesPeking UniversityBeijing 100871China Peking-Tsinghua Center for Life Sciences Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China cE3c-Centre for Ecology Evolution and Environmental Changes/Azorean Biodiversity GroupFaculdade de Ciencias Agrarias e do AmbienteUniversidade dos Açores9700-042 Angra do HeroísmoTerceiraPortugal

Mountains are rich in biodiversity,and butterflies are species-rich and have a good ecological and evolutionary research *** review addresses the potential and progress of studying mountain biodiversity using butterflies as a *** discuss the uniqueness of mountain ecosystems,factors influencing the distribution of mountain butterflies,representative genetic and evolutionary models in butterfly research,and evolutionary studies of mountain biodiversity involving butterfly genetics and ***,we demonstrate the necessity of studying mountain butterflies and propose future *** review provides insights for studying the biodiversity of mountain butterflies as well as a summary of research methods for reference.

关键词： Mountain ecosystem Butterfly Biodiversity Adaptation Genomics Genetics

A Joint Activity and Data Detection Scheme for Asynchronous Grant-Free Rateless Multiple Access

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China Communications 2024年第1期21卷 34-52页

作者： wei zhang Xiaofeng Zhong Shidong Zhou Department of Electronic Engineering Tsinghua UniversityBeijing 100084China

This paper considers the frameasynchronous grant-free rateless multiple access(FAGF-RMA)scenario,where users can initiate access at any symbol time,using shared channel resources to transmit data to the base *** coding is introduced to enhance the reliability of the *** literature has shown that FA-GFRMA can achieve lower access delay than framesynchronous grant-free rateless multiple access(FSGF-RMA),with extreme reliability enabled by rateless *** support FA-GF-RMA in more practical scenarios,a joint activity and data detection(JADD)scheme is *** the feature of sporadic traffic,approximate message passing(AMP)is exploited for transmission signal matrix ***,to determine the packet start points,a maximum posterior probability(MAP)estimation problem is solved based on the recovered transmitted signals,leveraging the intrinsic power pattern in the *** iterative power-pattern-aided AMP algorithm is devised to enhance the estimation performance of *** results verify that the proposed solution achieves a delay performance that is comparable to the performance limit of FA-GF-RMA.

关键词： asynchronous grant-free JADD rateless codes