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Anionically-Reinforced Nanocellulose Separator Enables Dual Suppression of Zinc Dendrites and Polyiodide Shuttle for Long-Cycle Zn-I_(2) Batteries
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作者 Wenhui Liu Hong Ma +4 位作者 Lingli Zhao Weiwei Qian Bo Liu Jizhang Chen Yagang Yao 《Nano-Micro Letters》 2026年第2期569-583,共15页
Zn-I_(2) batteries have emerged as promising next-generation energy storage systems owing to their inherent safety,environmental compatibility,rapid reaction kinetics,and small voltage hysteresis.Nevertheless,two crit... Zn-I_(2) batteries have emerged as promising next-generation energy storage systems owing to their inherent safety,environmental compatibility,rapid reaction kinetics,and small voltage hysteresis.Nevertheless,two critical challenges,i.e.,zinc dendrite growth and polyiodide shuttle effect,severely impede their commercial viability.To conquer these limitations,this study develops a multifunctional separator fabricated from straw-derived carboxylated nanocellulose,with its negative charge density further reinforced by anionic polyacrylamide incorporation.This modification simultaneously improves the separator’s mechanical properties,ionic conductivity,and Zn^(2+)ion transfer number.Remarkably,despite its ultrathin 20μm profile,the engineered separator demonstrates exceptional dendrite suppression and parasitic reaction inhibition,enabling Zn//Zn symmetric cells to achieve impressive cycle life(>1800 h at 2 m A cm^(-2)/2 m Ah cm^(-2))while maintaining robust performance even at ultrahigh areal capacities(25 m Ah cm^(-2)).Additionally,the separator’s anionic characteristic effectively blocks polyiodide migration through electrostatic repulsion,yielding Zn-I_(2) batteries with outstanding rate capability(120.7 m Ah g^(-1)at 5 A g^(-1))and excellent cyclability(94.2%capacity retention after 10,000 cycles).And superior cycling stability can still be achieved under zinc-deficient condition and pouch cell configuration.This work establishes a new paradigm for designing high-performance zinc-based energy storage systems through rational separator engineering. 展开更多
关键词 Zinc-iodine batteries Nanocellulose separators Carboxyl functional groups Polyiodide shuttle effect Dendrite suppression
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Prelaunch rolling suppression for maritime rockets using RF-AdaBoost
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作者 WANG Deng XIAO Wenhao +1 位作者 SHAO Jianshuai JIANG Yi 《Journal of Systems Engineering and Electronics》 2026年第1期197-210,共14页
Prelaunch rolling of maritime rockets threatens the reliability of launch in rough sea conditions.In order to suppress the prelaunch rolling,this study introduces advanced smart prediction designed especially for mari... Prelaunch rolling of maritime rockets threatens the reliability of launch in rough sea conditions.In order to suppress the prelaunch rolling,this study introduces advanced smart prediction designed especially for maritime rockets.The suggested approach introduces a hybrid model that combines random forest(RF)and Adaptive boosting(Ada Boost)methods to describe the coupling mechanism of factors affecting rocket rolling and to suppress the rolling.This combination improves forecast accuracy.Thereafter,the dimensionality reduced response surfaces are used to visually present the coupling between rocket rolling and influencing factors,which reveals the prelaunch rolling mechanism.When angle between the launch device and the ship's bow is within 80°-100°,the dynamic friction coefficient between adapters and guideways is 0.4,and the dynamic friction coefficient between the rocket and launchpad is within 0-0.15 or0.5-0.7,the prelaunch rolling of rocket during one motion cycle of the ship is less than 0.065°,originally 0.27°,reduced by 75.93%,effectively suppressing the prelaunch rolling.This study improves the prelaunch stability of maritime rockets in rough sea conditions and establishes a mapping relationship between the factors affecting rocket rolling and the structure of the sea launch system,guiding the optimization of future sea launch systems. 展开更多
关键词 prelaunch rolling maritime rocket maritime dynamic platform rolling suppression random forest(RF)-AdaBoost
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Enhancing SS-OCT 3D image reconstruction:A real-time system with stripe artifact suppression and GPU parallel acceleration
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作者 Dandan LIU 《虚拟现实与智能硬件(中英文)》 2026年第1期115-130,共16页
Optical coherence tomography(OCT),particularly Swept-Source OCT,is widely employed in medical diagnostics and industrial inspections owing to its high-resolution imaging capabilities.However,Swept-Source OCT 3D imagin... Optical coherence tomography(OCT),particularly Swept-Source OCT,is widely employed in medical diagnostics and industrial inspections owing to its high-resolution imaging capabilities.However,Swept-Source OCT 3D imaging often suffers from stripe artifacts caused by unstable light sources,system noise,and environmental interference,posing challenges to real-time processing of large-scale datasets.To address this issue,this study introduces a real-time reconstruction system that integrates stripe-artifact suppression and parallel computing using a graphics processing unit.This approach employs a frequency-domain filtering algorithm with adaptive anti-suppression parameters,dynamically adjusted through an image quality evaluation function and optimized using a convolutional neural network for complex frequency-domain feature learning.Additionally,a graphics processing unit integrated 3D reconstruction framework is developed,enhancing data processing throughput and real-time performance via a dual-queue decoupling mechanism.Experimental results demonstrate significant improvements in structural similarity(0.92),peak signal-to-noise ratio(31.62 dB),and stripe suppression ratio(15.73 dB)compared with existing methods.On the RTX 4090 platform,the proposed system achieved an end-to-end delay of 94.36 milliseconds,a frame rate of 10.3 frames per second,and a throughput of 121.5 million voxels per second,effectively suppressing artifacts while preserving image details and enhancing real-time 3D reconstruction performance. 展开更多
关键词 Stripe artifact suppression 3D reconstruction GPU parallel computing Adaptive frequency domain filtering Convolutional neural network
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Chirality-Induced Suppression of Singlet Oxygen in Lithium-Oxygen Batteries with Extended Cycle Life
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作者 Kyunghee Chae Youngbi Kim +11 位作者 Yookyeong Oh Hosik Hahn Jaehyun Son Youngsin Kim Hyuk‑Joon Kim Hyun Jeong Lee Dohyub Jang Jooho Moon Kisuk Kang Jeong Woo Han Filipe Marques Mota Dong Ha Kim 《Nano-Micro Letters》 2026年第2期124-137,共14页
Lithium-oxygen(Li-O2)batteries are perceived as a promising breakthrough in sustainable electrochemical energy storage,utilizing ambient air as an energy source,eliminating the need for costly cathode materials,and of... Lithium-oxygen(Li-O2)batteries are perceived as a promising breakthrough in sustainable electrochemical energy storage,utilizing ambient air as an energy source,eliminating the need for costly cathode materials,and offering the highest theoretical energy density(~3.5 k Wh kg^(-1))among discussed candidates.Contributing to the poor cycle life of currently reported Li-O_(2)cells is singlet oxygen(1O_(2))formation,inducing parasitic reactions,degrading key components,and severely deteriorating cell performance.Here,we harness the chirality-induced spin selectivity effect of chiral cobalt oxide nanosheets(Co_(3)O_(4)NSs)as cathode materials to suppress 1O_(2)in Li-O_(2)batteries for the first time.Operando photoluminescence spectroscopy reveals a 3.7-fold and 3.23-fold reduction in 1O_(2)during discharge and charge,respectively,compared to conventional carbon paperbased cells,consistent with differential electrochemical mass spectrometry results,which indicate a near-theoretical charge-to-O_(2)ratio(2.04 e-/O_(2)).Density functional theory calculations demonstrate that chirality induces a peak shift near the Fermi level,enhancing Co 3d-O 2p hybridization,stabilizing reaction intermediates,and lowering activation barriers for Li_(2)O_(2)formation and decomposition.These findings establish a new strategy for improving the stability and energy efficiency of sustainable Li-O_(2)batteries,abridging the current gap to commercialization. 展开更多
关键词 Singlet oxygen suppression Chirality-induced spin selectivity effect Lithium–oxygen batteries Oxygen evolution reaction Battery stability
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Suppression of Dry-Coupled Rubber Layer Interference in Ultrasonic Thickness Measurement:A Comparative Study of Empirical Mode Decomposition Variants
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作者 Weichen Wang Shaofeng Wang +4 位作者 Wenjing Liu Luncai Zhou Erqing Zhang Ting Gao Grigory Petrishin 《Structural Durability & Health Monitoring》 2026年第1期302-316,共15页
In dry-coupled ultrasonic thickness measurement,thick rubber layers introduce high-amplitude parasitic echoes that obscure defect signals and degrade thickness accuracy.Existing methods struggle to resolve overlap-pin... In dry-coupled ultrasonic thickness measurement,thick rubber layers introduce high-amplitude parasitic echoes that obscure defect signals and degrade thickness accuracy.Existing methods struggle to resolve overlap-ping echoes under variable coupling conditions and non-stationary noise.This study proposes a novel dual-criterion framework integrating energy contribution and statistical impulsivity metrics to isolate specimen re-flections from coupling-layer interference.By decomposing A-scan signals into Intrinsic Mode Functions(IMFs),the framework employs energy contribution thresholds(>85%)and kurtosis indices(>3)to autonomously select IMFs containing valid specimen echoes.Hybrid time-frequency thresholding further suppresses interference through amplitude filtering and spectral focusing.Experimental results demonstrate the framework’s robustness,achieving 92.3%thickness accuracy for 5 mm steel specimens with 5 mm rubber coupling,outperforming conventional methods by up to 18.7%.The dual-criterion approach reduces operator dependency by 37%and maintainsΔT<0.03 mm under surface roughness up to 6.3μm,offering a practical solution for industrial nondestructive testing with thick dry-coupled interfaces. 展开更多
关键词 Empirical mode decomposition complete ensemble EMD with adaptive noise(CEEMDAN) dry-coupled ultrasonic testing thickness measurement signal interference suppression
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Nonuniform Three-dimensional Configuration Distributed SAR Signal Reconstruction Clutter Suppression 被引量:4
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作者 LIU Mei ZHANG Lei LI Chenlei 《Chinese Journal of Aeronautics》 SCIE EI CSCD 2012年第3期423-429,共7页
This paper deals with the problem of clutter suppression in spaceborne distributed synthetic aperture radar (D-SAR) with nonuniform three-dimensional (3D) configuration geometry. In order to make a breakthrough of... This paper deals with the problem of clutter suppression in spaceborne distributed synthetic aperture radar (D-SAR) with nonuniform three-dimensional (3D) configuration geometry. In order to make a breakthrough of the configuration limitation of the traditional space time adaptive processing (STAP) based on uniform array and improve the inhomogeneous clutter suppres- sion performance, this paper considers signal reconstrtiction technique using array interpolation to process the D-SAR signal. An array interpolation signal reconstruction method based on pitching-partition is derived then a signal reconstruction 3D-STAP clutter suppression method applied to nonuniform 3D configuration is proposed. In particular, the proposed method is compared with conventional methods and the performance analysis is carried out based on simulations. The improvement factor (IF) for clutter suppression is imported and reported as a benchmark on the clutter suppression effect. 展开更多
关键词 distributed synthetic aperture radar nonunitform 3D configuration clutter suppression signal reconstruction STAP
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Clutter suppression for hypersonic vehicle-borne radar with frequency diverse array 被引量:3
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作者 Xuzi Wu Zheng Liu Rong Xie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第3期481-492,共12页
The seriously range-ambiguous clutter is one of the main problems in clutter suppression for hypersonic vehicle-borne forward-looking radar. An approach based on the frequency diverse array (FDA) technique is proposed... The seriously range-ambiguous clutter is one of the main problems in clutter suppression for hypersonic vehicle-borne forward-looking radar. An approach based on the frequency diverse array (FDA) technique is proposed to mitigate the range ambiguous clutter. The frequency increment is designed to distinguish the clutter at ambiguous ranges and suppress the clutter by using a subspace projection algorithm. On the platform with high altitude or limited array antennas, the proposed method performs better for its independence of the elevation degrees-of-freedom (DOF). Finally, simulation results verify the effectiveness of the proposed method. 展开更多
关键词 hypersonic vehicle forward-looking array radar clutter suppression frequency diverse array
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CLUTTER SUPPRESSION METHOD IN GPR USING PARTICLE CLUSTERING 被引量:3
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作者 Lu Cewu Liu Xiaojun Zhao Bo Fang Guangyou 《Journal of Electronics(China)》 2009年第5期584-587,共4页
In this paper, a novel clutter suppression method in Ground Penetrating Radar (GPR) is proposed. Time segments of hill are represented by their corresponding particle in B-scan. Those particles in B-scan are clustered... In this paper, a novel clutter suppression method in Ground Penetrating Radar (GPR) is proposed. Time segments of hill are represented by their corresponding particle in B-scan. Those particles in B-scan are clustered to represent reflectors (such as buried targets, air-soil interface). The clusters of buried target have a particle sequence with single peak. Therefore, if the particles donot belong to the cluster of buried target, time segment they represent will be suppressed. Experimental results and simulation are provided to demonstrate that the new algorithm outperforms existing approaches. 展开更多
关键词 Ground Penetrating Radar (GPR) clutter suppression CLUSTERING
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Short-range clutter suppression method combining oblique projection and interpolation in airborne CFA radar 被引量:1
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作者 HU Yili ZHAO Yongbo +1 位作者 PANG Xiaojiao CHEN Sheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第1期92-102,共11页
The airborne conformal array(CFA)radar's clutter ridges are range-modulated,which result in a bias in the estimation of the clutter covariance matrix(CCM)of the cell under test(CUT),further,reducing the clutter su... The airborne conformal array(CFA)radar's clutter ridges are range-modulated,which result in a bias in the estimation of the clutter covariance matrix(CCM)of the cell under test(CUT),further,reducing the clutter suppression performance of the airborne CFA radar.The clutter ridges can be effectively compensated by the space-time separation interpolation(STSINT)method,which costs less computation than the space-time interpolation(STINT)method,but the performance of interpolation algorithms is seriously affected by the short-range clutter,especially near the platform height.Location distributions of CFA are free,which yields serious impact that range spaces of steering vector matrices are non-orthogonal complement and even no longer disjoint.Further,a new method is proposed that the shortrange clutter is pre-processed by oblique projection with the intersected range spaces(OPIRS),and then clutter data after being pre-processed are compensated to the desired range bin through the STSINT method.The OPIRS also has good compatibility and can be used in combination with many existing methods.At the same time,oblique projectors of OPIRS can be obtained in advance,so the proposed method has almost the same computational load as the traditional compensation method.In addition,the proposed method can perform well when the channel error exists.Computer simulation results verify the effectiveness of the proposed method. 展开更多
关键词 airborne conformal arrays(CFA)radar oblique projection intersected range space short-range clutter suppression
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Clutter Suppression Method in GPR Using the Convergence of Matrix Entropy 被引量:1
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作者 Ce-Wu Lu Xiao-Jun Liu +1 位作者 Bo Zhao Guang-You Fang 《Journal of Electronic Science and Technology》 CAS 2010年第4期333-336,共4页
A novel clutter suppression method in ground penetrating radar (GPR) is proposed. The preliminary result is obtained by using target resolution improved processing (TRIP). The preliminary result will be used as an... A novel clutter suppression method in ground penetrating radar (GPR) is proposed. The preliminary result is obtained by using target resolution improved processing (TRIP). The preliminary result will be used as an initial input for TRIP iteration. All TRIP iteration steps are the adaptive linear combination of the previous TRIP result and the preliminary result. This adaptive combination strategy can balance clutter suppression and target information protection, which is considered as a troublesome contradiction and a chronic problem in clutter suppression research. When the matrix entropy of iteration result converges, the algorithm can achieve a good result both in clutter suppression and target protection. Experimental results demonstrate that the new algorithm outperforms the existing approaches. 展开更多
关键词 clutter suppression ground penetrating radar signal processing.
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A Novel Clutter Suppression Algorithm for Low-Slow-Small Targets Detecting Based on Sparse Adaptive Filtering 被引量:5
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作者 Zeqi Yang Shuai Ma +2 位作者 Ning Liu Kai Chang Xiaode Lyu 《Journal of Beijing Institute of Technology》 EI CAS 2024年第1期54-64,共11页
Passive detection of low-slow-small(LSS)targets is easily interfered by direct signal and multipath clutter,and the traditional clutter suppression method has the contradiction between step size and convergence rate.I... Passive detection of low-slow-small(LSS)targets is easily interfered by direct signal and multipath clutter,and the traditional clutter suppression method has the contradiction between step size and convergence rate.In this paper,a frequency domain clutter suppression algorithm based on sparse adaptive filtering is proposed.The pulse compression operation between the error signal and the input reference signal is added to the cost function as a sparsity constraint,and the criterion for filter weight updating is improved to obtain a purer echo signal.At the same time,the step size and penalty factor are brought into the adaptive iteration process,and the input data is used to drive the adaptive changes of parameters such as step size.The proposed algorithm has a small amount of calculation,which improves the robustness to parameters such as step size,reduces the weight error of the filter and has a good clutter suppression performance. 展开更多
关键词 passive radar interference suppression sparse representation adaptive filtering
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Sea clutter suppression via cuttable encoder-decoderaugmentation network
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作者 ZANG Chuanfei WANG Yumiao +2 位作者 WANG Xiang XU Congan CUI Guolong 《Journal of Systems Engineering and Electronics》 CSCD 2024年第6期1428-1440,共13页
This paper considers the problem of sea clutter sup-pression.We propose the cuttable encoder-decoder-augmenta-tion network(CEDAN)to improve clutter suppression perfor-mance by enriching the contrast information betwee... This paper considers the problem of sea clutter sup-pression.We propose the cuttable encoder-decoder-augmenta-tion network(CEDAN)to improve clutter suppression perfor-mance by enriching the contrast information between the target and clutter.Specifically,the plug-and-play residual U-block(ResUblock)is proposed to augment the feature representation ability of the clutter suppression model.The CEDAN first extracts and fuses the multi-scale features using the encoder and the decoder composed of the ResUblocks.Then,the fused features are processed by the contrast information augmenta-tion module(CIAM)to enhance the diversity of target and clutter,resulting in encouraging sea clutter suppression results.In addi-tion,we propose the result-consistency loss to further improve the suppression performance.The result-consistency loss enables CEDAN to cut some blocks of decoder and CIAM to reduce the inference time without significantly degrading the suppression performance.Experimental results on measured and simulated data show that the CEDAN outperforms state-of-the-art sea clutter suppression methods in sea clutter suppres-sion performance and computation efficiency. 展开更多
关键词 RADAR sea clutter suppression deep learning
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Suppression of Log-Normal Distributed Weather Clutter Observed by an S-Band Radar
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作者 Shuji Sayama Seishiro Ishii 《Wireless Engineering and Technology》 2013年第3期125-133,共9页
We have observed weather clutter containing targets (ships) using an S-band radar with a frequency 3.05 GHz, a beam width 1.8°, and a pulsewidth 0.5 μs. To investigate the weather clutter amplitude statistics, w... We have observed weather clutter containing targets (ships) using an S-band radar with a frequency 3.05 GHz, a beam width 1.8°, and a pulsewidth 0.5 μs. To investigate the weather clutter amplitude statistics, we introduce the Akaike Information Criterion (AIC). We have found that the weather clutter amplitudes obey the log-normal, Weibull, and log-Weibull distributions with the shape parameters of 0.308 to 0.470, 4.42 to 4.51, and 15.91 to 16.44, respectively, for small data within the beam width of an antenna. We have proposed the log-normal/CFAR circuit modified a Cell-Averaging (CA) LOG/CFAR circuit. It is found that weather clutter is suppressed with improvement of 51.58 dB by log-normal/CFAR. As a result, we have showed that weather clutter observed by S-band radar does not obey the Rayleigh distribution and our log-normal/CFAR circuit has an effect on suppression of clutter and detection of target, while conventional LOG/CFAR circuit does not. In addition, if our circuit can be realized, we will have an advantage economically. 展开更多
关键词 CFAR S-BAND RADAR WEATHER clutter Log-Normal Distribution
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Experimental and Numerical Study on Vortex-Induced Vibration Suppression by Helical Strakes on Subsea Pipelines 被引量:1
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作者 Jinhong Yu Chen An +3 位作者 Yu Zhang Junkai Feng Zexin Xu Frank Lim 《哈尔滨工程大学学报(英文版)》 2025年第3期580-592,共13页
A numerical simulation analysis is conducted to examine the unsteady hydrodynamic characteristics of vortex-induced vibration(VIV)and the suppression effect of helical strakes on VIV in subsea pipelines.The analysis u... A numerical simulation analysis is conducted to examine the unsteady hydrodynamic characteristics of vortex-induced vibration(VIV)and the suppression effect of helical strakes on VIV in subsea pipelines.The analysis uses the standard k−εturbulence model for 4.5-and 12.75-inch pipes,and its accuracy is verified by comparing the results with large-scale hydrodynamic experiments.These experiments are designed to evaluate the suppression efficiency of VIV with and without helical strakes,focusing on displacement and drag coefficients under different flow conditions.Furthermore,the influence of important geometric parameters of the helical strakes on drag coefficients and VIV suppression efficiency at different flow rates is compared and discussed.Numerical results agree well with experimental data for drag coefficient and vortex shedding frequency.Spring-pipe self-excited vibration experimental tests reveal that the installation of helical strakes substantially reduces the drag coefficient of VIV within a certain flow rate range,achieving suppression efficiencies exceeding 90%with strake heights larger than 0.15D.Notably,the optimized parameter combination of helical strakes,with a pitch of 15D,a fin height of 0.2D,and 45°edge slopes,maintains high suppression efficiency,thereby exhibiting superior performance.This study provides a valuable reference for the design and application of helical strakes and VIV suppression in subsea engineering. 展开更多
关键词 Subsea pipeline Helical strakes Vortex-induced vibration Lift-drag coefficient suppression
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Staged dendrite suppression for high safe and stable lithium-sulfur batteries 被引量:1
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作者 Jun Jiang Zhenjie Lu +12 位作者 Yanwen Ding Shujun Liu Zhijie Qi Tian Tang Yunfan Zhang Zhiyuan Ma Jingwen Sun Liang Xue Wenyao Zhang Pan Xiong Xin Wang Junwu Zhu Yongsheng Fu 《Journal of Energy Chemistry》 2025年第1期674-683,共10页
The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur batteries.Herein,we propose a dual-action strategy to address the lithiu... The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur batteries.Herein,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene (PP) separator.The uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition stage.Most importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance(145.88 MPa) of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium dendrite.The Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm^(-2)with a polarization voltage of only 29.3 mV.Additionally,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity attenuation.The improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect. 展开更多
关键词 Lithium-sulfur batteries Staged dendrite suppression Shuttle effect Surface-negatively-charged nanodiamond
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Improved algorithm of multi-mainlobe interference suppression under uncorrelated and coherent conditions 被引量:1
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作者 CAI Miaohong CHENG Qiang +1 位作者 MENG Jinli ZHAO Dehua 《Journal of Southeast University(English Edition)》 2025年第1期84-90,共7页
A new method based on the iterative adaptive algorithm(IAA)and blocking matrix preprocessing(BMP)is proposed to study the suppression of multi-mainlobe interference.The algorithm is applied to precisely estimate the s... A new method based on the iterative adaptive algorithm(IAA)and blocking matrix preprocessing(BMP)is proposed to study the suppression of multi-mainlobe interference.The algorithm is applied to precisely estimate the spatial spectrum and the directions of arrival(DOA)of interferences to overcome the drawbacks associated with conventional adaptive beamforming(ABF)methods.The mainlobe interferences are identified by calculating the correlation coefficients between direction steering vectors(SVs)and rejected by the BMP pretreatment.Then,IAA is subsequently employed to reconstruct a sidelobe interference-plus-noise covariance matrix for the preferable ABF and residual interference suppression.Simulation results demonstrate the excellence of the proposed method over normal methods based on BMP and eigen-projection matrix perprocessing(EMP)under both uncorrelated and coherent circumstances. 展开更多
关键词 mainlobe interference suppression adaptive beamforming spatial spectral estimation iterative adaptive algorithm blocking matrix preprocessing
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Laser additive manufacturing of Ti and Ce co-modified 2195 difficult-to-process aluminum alloy:Grain refinement,cracking suppression and enhanced mechanical properties 被引量:1
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作者 Lixia XI Jiaxing HOU +3 位作者 Juncan XU He LIU Keyu SHI Dongdong GU 《Chinese Journal of Aeronautics》 2025年第8期604-621,共18页
High cracking susceptibility of Al-Li alloys with Ti/Ce B6addition is thoroughly suppressed in laser powder bed fusion(LPBF)processing of Ti/Ce co-modified 2195 alloys at relatively high scan speeds,while the cracking... High cracking susceptibility of Al-Li alloys with Ti/Ce B6addition is thoroughly suppressed in laser powder bed fusion(LPBF)processing of Ti/Ce co-modified 2195 alloys at relatively high scan speeds,while the cracking suppression mechanism and phase formation in these composites are not clarified.In this work,microstructure evolution and mechanical performance of the LPBF-fabricated Ti/Ce co-modified 2195 are investigated to reveal their cracking suppression and strengthening mechanisms.The results show that apparent grain refinement of the composites is ascribed to high supercooling from rapid formation of constitutional supercooling zone in front of solid–liquid interfaces by high-Q-value Ti solute,and heterogeneous nucleation of in situ formed Al3Ti and Al11Ce3precipitates.Their synergistic interactions promote formation of fine equiaxed grains and thus inhibit crack initiation.The composites exhibit high microhardness of 100±5HV0.2,nano-hardness of 1.6±0.1 GPa and elastic modulus of 97±3 GPa,where the elastic modulus increases by 27%and 31%compared to those of LPBF-processed and conventionally manufactured 2195 alloys,respectively.A tensile strength of 336 MPa and an elongation of 3%are obtained from in-situ synchrotron X-ray diffraction measurement.The improved properties are derived from grain refinement and Orowan strengthening.Based on the optimal processing parameter and composition,a bracket component filled with lattice structures is designed and manufactured with good manufacturing quality and processing accuracy. 展开更多
关键词 Laser powder bed fusion Ti/Ce co-modified 2195 alloy Grain refinement Cracking suppression Mechanical property
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Occluded Gait Emotion Recognition Based on Multi-Scale Suppression Graph Convolutional Network
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作者 Yuxiang Zou Ning He +2 位作者 Jiwu Sun Xunrui Huang Wenhua Wang 《Computers, Materials & Continua》 SCIE EI 2025年第1期1255-1276,共22页
In recent years,gait-based emotion recognition has been widely applied in the field of computer vision.However,existing gait emotion recognition methods typically rely on complete human skeleton data,and their accurac... In recent years,gait-based emotion recognition has been widely applied in the field of computer vision.However,existing gait emotion recognition methods typically rely on complete human skeleton data,and their accuracy significantly declines when the data is occluded.To enhance the accuracy of gait emotion recognition under occlusion,this paper proposes a Multi-scale Suppression Graph ConvolutionalNetwork(MS-GCN).TheMS-GCN consists of three main components:Joint Interpolation Module(JI Moudle),Multi-scale Temporal Convolution Network(MS-TCN),and Suppression Graph Convolutional Network(SGCN).The JI Module completes the spatially occluded skeletal joints using the(K-Nearest Neighbors)KNN interpolation method.The MS-TCN employs convolutional kernels of various sizes to comprehensively capture the emotional information embedded in the gait,compensating for the temporal occlusion of gait information.The SGCN extracts more non-prominent human gait features by suppressing the extraction of key body part features,thereby reducing the negative impact of occlusion on emotion recognition results.The proposed method is evaluated on two comprehensive datasets:Emotion-Gait,containing 4227 real gaits from sources like BML,ICT-Pollick,and ELMD,and 1000 synthetic gaits generated using STEP-Gen technology,and ELMB,consisting of 3924 gaits,with 1835 labeled with emotions such as“Happy,”“Sad,”“Angry,”and“Neutral.”On the standard datasets Emotion-Gait and ELMB,the proposed method achieved accuracies of 0.900 and 0.896,respectively,attaining performance comparable to other state-ofthe-artmethods.Furthermore,on occlusion datasets,the proposedmethod significantly mitigates the performance degradation caused by occlusion compared to other methods,the accuracy is significantly higher than that of other methods. 展开更多
关键词 KNN interpolation multi-scale temporal convolution suppression graph convolutional network gait emotion recognition human skeleton
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Nonperiodic interrupted sampling repeater jamming suppression for inverse synthetic aperture radar 被引量:1
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作者 WU Qihua ZHAO Feng +3 位作者 ZHAO Tiehua LIU Xiaobin XU Zhiming XIAO Shunping 《Journal of Systems Engineering and Electronics》 2025年第4期940-950,共11页
Nonperiodic interrupted sampling repeater jamming(ISRJ)against inverse synthetic aperture radar(ISAR)can obtain two-dimensional blanket jamming performance by joint fast and slow time domain interrupted modulation,whi... Nonperiodic interrupted sampling repeater jamming(ISRJ)against inverse synthetic aperture radar(ISAR)can obtain two-dimensional blanket jamming performance by joint fast and slow time domain interrupted modulation,which is obviously dif-ferent from the conventional multi-false-target deception jam-ming.In this paper,a suppression method against this kind of novel jamming is proposed based on inter-pulse energy function and compressed sensing theory.By utilizing the discontinuous property of the jamming in slow time domain,the unjammed pulse is separated using the intra-pulse energy function diffe-rence.Based on this,the two-dimensional orthogonal matching pursuit(2D-OMP)algorithm is proposed.Further,it is proposed to reconstruct the ISAR image with the obtained unjammed pulse sequence.The validity of the proposed method is demon-strated via the Yake-42 plane data simulations. 展开更多
关键词 jamming suppression compressed sensing(CS) interrupted sampling repeater jamming(ISRJ) energy function inverse synthetic aperture radar(ISAR).
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Sustained maternal human immunodeficiency virus viral load suppression and cascade of human immunodeficiency virus testing among exposed infants in Rwanda 被引量:1
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作者 Hafidha Mhando Bakari Jackson Sebeza +6 位作者 Haji Mbwana Ally Hassan Fredrick Fussi Habib Omari Ramadhani Peter Memiah Djemima Umutesi Basile Ikuzo Gallican Rwibasira 《World Journal of Virology》 2025年第2期67-78,共12页
BACKGROUND To prevent mother to child transmission(MTCT)of human immunodeficiency virus(HIV),sustained maternal viral load suppression(VLS)and early HIV testing among HIV exposed infants(HEI)is critical.AIM To investi... BACKGROUND To prevent mother to child transmission(MTCT)of human immunodeficiency virus(HIV),sustained maternal viral load suppression(VLS)and early HIV testing among HIV exposed infants(HEI)is critical.AIM To investigate maternal viral load results and infant HIV testing uptake at 6-weeks,and 9-months and 18-months in Rwanda.METHODS Between 2015 and 2022,VLS(<200 copies/mL)was measured among pregnant women living with HIV(WLHIV)from 38-healthcare facilities.Viral loads(VL)were measured at 6-months,12-months and 24-months,respectively.For maternal VL,the unit of analysis was visit-pair,and the pairs were created to define those with VL<200 copies/mL at two consecutive visits as having sustained VLS,persistent viremia(VL≥200 copies/mL at two consecutive visits),viral rebound(VL<200 copies/mL at prior visit only)and newly suppressed(VL<200 copies/mL at subsequent visit only).HEI were considered to have persistent HIV testing if they had all three HIV tests.Poisson regression models with generalized estimating equations were used to estimate the adjusted incidence rate ratio(aIRR)and 95%CI for factors associated with sustained VLS and persistent HIV testing.RESULTS A total of 1145 mother-infant pairs were analyzed.Infant HIV testing uptake at 6-weeks,9-months and 18-months was 1145(100.0%),1089(95.1%),1006(87.9%)respectively.Nine hundred ninety-nine HEI(87.3%)tested for HIV persistently.At 18-months,the incidence of HIV among HEI was 8(0.7%).Of 1145 mothers,1076(94.0%)had≥2 VL results making a total of 2010 visit-pairs(142-single;934-double visit-pairs).The incidence rate of sustained VLS,persistent viremia,viral rebound and new suppression were 91.0%,1.3%,3.6%and 4.0%respectively.Maternal disclosure of HIV status(aIRR=1.08,95%CI:1.02-1.14)was associated with increased likelihood of sustained VLS.Having peer support(aIRR=1.0595%CI:1.01-1.10)was associated with persistent HIV testing among HEI.CONCLUSION Sustained VLS is high among pregnant WLHIV in Rwanda.The low incidence of HIV among HEI may be attributed to high VLS levels.Targeted interventions,including enhanced HIV disclosure and peer support,are crucial for improving sustained VLS and increasing infant HIV testing uptake to reduce MTCT. 展开更多
关键词 Sustained viral load suppression Mother to child human immunodeficiency virus transmission Women living with human immunodeficiency virus Human immunodeficiency virus exposed infants Human immunodeficiency virus testing Rwanda
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