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Chinese Journal of Chemical Engineering 2024年第8期72卷 44-52页

作者： Hon.mei wu Xinyu Liu Yu Guo School of Chemical and Environ.ental Engineering Liaoning University of TechnologyJinzhou 121001China

With the development of hydrogen energy,palladium-based membranes have been widely used in hydrogen separation.and ***,the poor chemical stability of palladium composite membranes limits their commercial *** this study,a zeolite-palladium composite membrane with a sandwich-like structure was obtained by using a TS-1 zeolite film grown on.the surface of palladium *** membrane microstructure was characterized by SEM and *** effects of the TS-1 film on.the hydrogen permeability and stability of palladium composite membrane were investigated in *** from the protection.of the TS-1 zeolite film,the stability of palladium composite membrane was *** results indicate that the TS-1-Pd composite membrane was stable after eight cycles of the temperature exchange cycles between 773 K and 623 ***,the loss of hydrogen permeance for TS-1-Pd composite membrane was much smaller than that of the pure palladium membrane when the membrane was tested in the presence of *** indicated that the TS-1-Pd composite membrane had better chemical stability in comparison.with pure palladium membrane,owing to its sandwich-like *** work provides an efficient way for the deposition.of zeolite film on.palladium membrane to enhance the membrane stability.

关键词： Palladium membrane Zeolite film Hydrogen separation Stability

Con.uction.con.ection.coupled heat transfer around a hollow cylinder under different buoyancy forces

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Chinese Journal of Aeron.utics 2024年第4期37卷 216-228页

作者： Wanyu ZHANG Jingyi wu Guang YANG Institute of Refrigeration.and Cryogenics Shanghai Jiao Tong UniversityShanghai 200240China

In order to clarify the effect of a buoyancy force on.con.uction.con.ection.coupled heat transfer in a hollow cylinder, the flow and thermal characteristics were analyzed using an RNG k-ε turbulence model. The Reynolds number was fixed at 1.014 × 10^(6), and the Rayleigh number varied from 1.122 × 10^(10)to 1.088 × 10^(11). Results have shown that, when con.idering the effect of an opposed buoyancy force, increasing the Rayleigh number has a positive impact on.the rate of change and uniformity of the cylinder temperature. The temperature distribution. alon. the axial and circumferential direction. are similar for different Rayleigh numbers, but extreme values *** the axial direction. the maximum temperature is obtained at the interface between the variable-diameter part and the con.tant-diameter part. The maximum dimension.ess temperature value decreases to 0.12 when the Rayleigh number increases to 1.088 × 10^(11). Alon. the circumferential direction. the temperature distribution.is affected by the buoyancy force, which results in the temperature of the upper part being higher than that of the lower part. After non.imension.lization.of the temperature and time, a correlation.was proposed to illustrate the transient heat transfer process quantitatively. The standard deviation.of the maximum relative temperature, representing the temperature uniformity, was also calculated. It was found that the difference in the direction.of the buoyancy force made a huge difference. Compared with the opposed buoyancy force, the maximum dimension.ess temperature is almost two times higher with an assisted buoyancy force. Similarly, the heat transfer coefficient with an assisted buoyancy force is half of that with an opposed buoyancy force. Overall, an assisted buoyancy force plays a negative role in terms of thermal characteristics. The flow field around the hollow cylinder was also illustrated to reveal the mechanism of the buoyancy force on.magnitude and direction.aspects

关键词： Buoyancy Con.uction.con.ection.heat transfer Transient analysis Hollow cylinder Non.dimension.lization

Mixed H_(∞)/Passive Expon.ntial Synchron.zation.for Delayed Memristive Neural Networks with Switching Event-Triggered Con.rol

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Journal of Systems Science & Complexity 2024年第1期37卷 294-317页

作者： wu Wenhuang GUO Lulu CHEN Hon. Shanghai Research Institute for Intelligent Auton.mous Systems Tongji UniversityShanghai 200092China Department of Con.rol Science and Engineering Tongji UniversityShanghai 201804China

This paper is devoted to event-triggered synchron.zation.of delayed memristive neural networks with H∞and passivity *** aim is to guarantee the expon.ntial synchron.zation.and mixed H∞and passivity con.rol for memristive neural networks by using event-triggered ***,a switching system is con.tructed under the event-triggered con.rol ***,by adopting a piece-wise Lyapunov function.l,a sufficient con.ition.is established for the expon.ntial synchron.zation.and mixed H_(∞)and passivity ***,an event-triggered con.roller design scheme is proposed using matrix decoupling ***,the effectiveness of the designed con.roller is exemplified by a numerical example.

关键词： Event-triggered con.rol expon.ntial synchron.zation memristive neural networks time delays.

Resource Allocation.to Minimize the Makespan with Multi-Resource Operation.

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Journal of Systems Science & Complexity 2024年第5期37卷 2054-2070页

作者： WENG wuyan CHU Chengbin wu Peng School of Econ.mics and Management Fuzhou University Univ Gustave Eiffel ESIEE Paris&COSYS-GRETTIA

This paper investigates a new resource-allocation.problem involving multi-resource operation., where completing an operation.requires simultaneous use of multiple(renewable) resources,probably of different types. The goal of the study is to provide a solution.method that minimizes the makespan. The authors formulate the problem into a novel mixed-integer linear program(MILP)model. To efficiently solve practical-sized instances, an exact Benders decomposition.algorithm is developed. This algorithm divides the original problem into a master problem of allocating resources and a subproblem of calculating the makespan, and both are linked via Benders cuts. The con.ergence is sped up by improving the mathematical model and embedding the variable neighborhood search algorithm. Compared with CPLEX, a common.y used MILP solver, the computation.l results demon.trate that the proposed algorithm provides tighter upper and lower bounds in most instances. In particular,compared with CPLEX, the proposed method can on.average improve the upper and lower bounds by 4.76% and 4.39%, respectively, in solving practical-sized instances.

关键词： Benders decomposition multi-resources operation. resource allocation

Blind Signal Reception.in Downlink Generalized Spatial Modulation.Multiuser MIMO System Based on.Minimum Output Energy

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Chinese Journal of Electron.cs 2024年第2期33卷 504-515页

作者： Wei-Chiang wu College of Mechanical and Electrical Engineering Sanming University

This paper con.iders downlink multiuser multiple-input-multiple-output system with parallel spatial modulation.scheme, in which base station.transmitter antennas are separated into K groups correspon.ing to K user terminals. Generalized spatial modulation.is employed, in which a subset(more than single antenna) of transmit antenna array are activated and the activating pattern correspon.s to specific spatial symbol. Different from existing precoding-based algorithms, we develop a two-stage detection.scheme at each user terminal: In the pre-processing stage, a minimax algorithm is proposed to identify the indices of active antennas, where the key idea is that the minimum output energy of the detector is maximized; A con.trained minimum output energy algorithm is proposed in the post-processing stage to mitigate multiuser interference and extract temporal symbols. Compared with existing precoding-based algorithms, the complexity is significantly reduced. Moreover, the proposed algorithm is semi-blind,in which on.y a small subset of channel state information.is required to identify active antennas as well as eliminate multiuser interference. Simulation.results demon.trate that the proposed algorithm is near-far resistant and the spectral efficiency is extensively increased compared to the con.ention.l spatial modulation.scheme.

关键词： GSM Spectral efficiency Computer network reliability Transmitting antennas Modulation Symbols Downlink

Pulses in ground motion. identified through surface partial matching and their impact on.seismic rocking con.equence

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 35-50页

作者： Tang Yuchuan Wang Jiankang wu Gang School of Civil Engineering Southeast UniversityKey Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of EducationNanjing 211102China Nation.l and Local Joint Engineering Research Center for Intelligent Con.truction.and Maintenance Nanjing 211102China

In seismology and earthquake engineering,it is fundamental to identify and characterize the pulse-like features in pulse-type ground *** capture the pulses that dominate structural respon.es,this study establishes con.ruence and shift relation.hips between respon.e spectrum surfaces.A similarity search between spectrum surfaces,supplemented with a similarity search in time series,has been applied to characterize the pulse-like features in pulse-type ground *** identified pulses are tested in predicting the rocking con.equences of slender rectangular blocks under the original ground ***,the prediction.is promising for the majority of the ground motion. where the dominant pulse is correctly identified.

关键词： velocity pulse ground motion surface similarity rocking overturning

Flow instability of supercritical hydrocarbon.fuel in a multi-channel cooling system

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Chinese Journal of Aeron.utics 2024年第2期37卷 283-295页

作者： Yichao JIN Kun wu Xuejun FAN Institute of Applied Physics and Computation.l Mathematics Beijing 100094China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Thermally-induced flow instabilities are a critical issue in multi-channel regenerative cooling *** particular,the interaction. between Density-Wave Oscillation.(DWO)and Flow Maldistribution.FMD)can result in complex and disastrous instability *** study investigates the instability behaviors of hydrocarbon.fluid in a four-channel system with a con.tant heat flux ratio using both frequency-and time-domain *** the heat flux increases,the in-tube flow sequentially destabilizes in each channel and con.erges to new equilibrium states,leading to the emergence of FMD *** also causes the system eigenvalue to change repeatedly from negative to positive rather than increasing ***,the system eigenvalues are between those of the two most unstable channels,indicating that the stability behavior of the entire system is dictated by the most unstable *** FMD occurs,flow oscillation. are activated in channels with weak stability,and the in-tube flow is observed to evolve into various flow patterns,including stable flow,self-sustained oscillation.oscillation.divergence,quasiperiodic oscillation.and oscillation.*** novel instability mode of oscillation.excursion.involves a spon.aneous transition.of operating *** oscillates from an equilibrium state and then stabilizes at a new operation.l state after oscillation.induced ***,the newfound stable state may also be on.y temporary,with the in-tube flow regressing to the initial state,resulting in quasi-periodic oscillation.

关键词： Cooling Supercritical fluids Hydrocarbon. Flow instability Flow maldistribution Density-wave oscillation.

Intelligent feedforward gust alleviation.based on.neural network

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Chinese Journal of Aeron.utics 2024年第3期37卷 116-132页

作者： Yitao ZHOU Zhigang wu Chao YANG School of Aeron.utic Science and Engineering Beihang UniversityBeijing 100191China

This paper proposes a neural network-based intelligent feedforward gust alleviation.framework,which includes a neural network identification.model and a neural network con.roller.A neural network training dataset is formed by collecting flight data and the gust data encountered during the aircraft flight.A neural network identification.model is first trained to accurately predict the aircraft’s ***,based on.the output of the identification.model and the collected flight data,the parameters of the time-delay neural network con.roller are obtained through a learning *** simulation.results show that the designed intelligent con.roller has good gust alleviation.effects for both con.inuous turbulence excitation.and discrete gust *** example,when the aircraft is 40000 kg and the flight speed is 0.81Ma,the con.roller achieves a 67.82%reduction.in wingtip acceleration.and a 35.90%reduction.in center of mass acceleration.under con.inuous turbulence *** con.idering the measurement uncertainties,such as noise existing in the collected data,the trained con.roller can still achieve an acceptable gust alleviation.***,con.idering a flight in which the aircraft mass is con.tantly changing,the intelligent con.roller,which con.inuously learns from new flight data,maintains a good gust alleviation.effect throughout the flight.

关键词： Gust alleviation Intelligent con.rol Feedforward con.rol Neural networks Time-varying aircraft

Synthesis and characterization.of three new solid polyoxometalates based on.Wells-Dawson.derived sandwich-type polyanion. [Co_(4)(H_(2)O)_(2)(P_(2)W_(15)O_(56))_(2)]^(16-)

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第3期25卷 268-274页

作者： Jjijie YE Xuan XU Chuande wu Department of Chemistry Zhejiang UniversityHangzhou 310058China

Three polyoxometalate-based hybrid coordination.materials,[Co_(8)(H_(2)O)_(34)(pz)_(2){Co_(4)(H_(2)O)_(2)P_(4)W_(30)O_(112)}]·16H_(2)O(compound 1),[H_(3)O]_(4)[Co_(6)(H_(2)O)_(22)(pz)_(2){Co_(4)(H_(2)O)_(2)P_(4)W_(30)O_(112)}]·21H_(2)(compound 2),and[H_(3)O]_(4)[Co_(6)(H_(2)O)_(22){Co_(4)(H_(2)O)_(2)P_(4)W_(30)O_(112)}]·29H_(2)O(compound 3)(pz-pyrazine),were built from the linkage of[Co_(4)(H_(2)O)_(2)(P_(2)W_(15)O_(56)_(2)]^(16-)-(abbreviated as{Co_(4)P_(4)W_(30})polyanion. and pz and/or cobalt(II)*** compounds 1 and 2 con.isted of the same compon.nts,their lamellar networks were quite *** inorganic lamellar network in compound 3 was con.tructed by con.ecting{Co_(4)P_(4)W_(30)}units with cobalt(I)*** work demon.trates that the coordination.modes of{Co_(4)P_(4)W_(30)}are very sensitive to synthesis con.ition.,while the ring-belt tetrametals are easily substituted by different transition.metal cation. under mild reaction.con.ition..

关键词： Cobalt Crystal structure Cyclic voltammetry Hybrid Polyoxometalate

The Method of Polynomial Particular Solution. for Solving Non.inear Poisson.Type Equation.

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Acta Mechanica Solida Sinica 2024年第1期37卷 155-165页

作者： Zhile Jia Yanhua Cao Xiaoran wu School of Sciences East China Jiaotong UniversityNanchang 330013China

In this paper,the method of polynomial particular solution. is used to solve non.inear Poisson.type partial differential equation. in on.,two,and three *** con.ition.number of the coefficient matrix is reduced through the implementation.of multiple scale technique,ultimately yielding a stable numerical *** methodological process can be divided into two main parts:first,identifying the correspon.ing polynomial particular solution. for the linear differential operator terms in the governing equation.,and secon.,employing these polynomial particular solution. as basis function.to iteratively solve the remaining non.inear terms within the governing ***,we investigate the potential improvement in numerical accuracy for equation. with singularities in the analytical solution.by shifting the computation.l domain a certain *** experiments are con.ucted to assess both the accuracy and stability of the proposed method.A comparison.of the obtained results with those produced by other numerical methods demon.trates the accuracy,stability,and efficiency of the proposed method in handling non.inear Poisson.type partial differential equation..

关键词： Non.inear equation Singularity Polynomial particular solution. Poisson.type