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Co-production of hydrogen, oxygen, and electricity via an integrated solar-driven system with decoupled water electrolyzer and Na-Zn ion battery
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作者 Fei Lv Longjie Liu +4 位作者 Jiazhe Wu Pengfei Wang Lixia Pan Dengwei Jing Yubin Chen 《Journal of Energy Chemistry》 2025年第1期621-627,共7页
Combining water electrolysis and rechargeable battery technologies into a single system holds great promise for the co-production of hydrogen (H_(2)) and electricity.However,the design and development of such systems ... Combining water electrolysis and rechargeable battery technologies into a single system holds great promise for the co-production of hydrogen (H_(2)) and electricity.However,the design and development of such systems is still in its infancy.Herein,an integrated hydrogen-oxygen (O_(2))-electricity co-production system featuring a bipolar membrane-assisted decoupled electrolyzer and a Na-Zn ion battery was established with sodium nickelhexacyanoferrate (NaNiHCF) and Zn^(2+)/Zn as dual redox electrodes.The decoupled electrolyzer enables to produce H_(2)and O_(2)in different time and space with almost 100%Faradaic efficiency at 100 mA cm^(-2).Then,the charged NaNiHCF and Zn electrodes after the electrolysis processes formed a Na-Zn ion battery,which can generate electricity with an average cell voltage of 1.75 V at 10 m A cm^(-2).By connecting Si photovoltaics with the modular electrochemical device,a well-matched solar driven system was built to convert the intermittent solar energy into hydrogen and electric energy with a solar to hydrogen-electricity efficiency of 16.7%,demonstrating the flexible storage and conversion of renewables. 展开更多
关键词 HYDROGEN ELECTRICITY decoupled water electrolyzer Na-Zn ion battery Solar energy
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Advanced approaches to decoupled sensory signal monitoring in human interface systems
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作者 Se Gi Lee Ki Jun Yu +1 位作者 Sang Min Won Jae-Young Yoo 《International Journal of Extreme Manufacturing》 2025年第4期56-76,共21页
Real-time sensory signal monitoring systems are crucial for continuous health tracking and enhancing human-interface technologies in virtual reality/augmented reality applications.Recent advancements in micro/nanofabr... Real-time sensory signal monitoring systems are crucial for continuous health tracking and enhancing human-interface technologies in virtual reality/augmented reality applications.Recent advancements in micro/nanofabrication technologies have enabled wearable and implantable sensors to achieve sufficient sensitivity for measuring subtle sensory signals,while integration with wireless communication technologies allows for real-time monitoring and closed-loop user feedback.However,highly sensitive sensing materials face challenges,as their detection results can easily be altered by external factors such as bending,temperature,and humidity.This review discusses methods for decoupling various stimuli and their applications in human interfaces.We cover the latest advancements in decoupled systems,including the design of sensing materials using micro/nanostructured materials,3-dimensional(3D)sensory system architectures,and Artificial intelligence(AI)-based signal decoupling processing techniques.Additionally,we highlight key applications in robotics,wearable,and implantable health monitoring made possible by these decoupled systems.Finally,we suggest future research directions to address the remaining challenges of developing decoupled artificial sensory systems that are resilient to external stimuli. 展开更多
关键词 decoupled sensory systems micro/nanostructured material 3D sensory system architectures AI-based signal decoupling
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Power System State Estimation Solution With Zero Injection Constraints Using Modified Newton Method and Fast Decoupled Method in Polar Coordinate 被引量:12
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作者 GUO Ye ZHANG Boming +1 位作者 WU Wenchuag SUN Hongbin 《中国电机工程学报》 EI CSCD 北大核心 2012年第22期I0015-I0015,11,共1页
In actual power systems,most of the high-voltage buses of the transformers are zero injection buses without load or generation.Power injections into these buses are strictly 0,so based on Kirchhoff's current law(K... In actual power systems,most of the high-voltage buses of the transformers are zero injection buses without load or generation.Power injections into these buses are strictly 0,so based on Kirchhoff's current law(KCL),equality constraints should be used to handle these buses in a state estimation model.It is a challenge to ensure that these zero injection constraints can be strictly satisfied without losing computational efficiency. 展开更多
关键词 state estimation zero injection equality constraints polar coordinate modified Newton method modified fast decoupled state estimation
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Decoupled Wiener state fuser for descriptor systems 被引量:1
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作者 Chenjian RAN Zili DENG 《控制理论与应用(英文版)》 EI 2008年第4期365-371,共7页
By the modem time series analysis method, based on the autoregressive moving average (ARMA) innovation models and white noise estimation theory, using the optimal fusion rule weighted by diagonal matrices, a distrib... By the modem time series analysis method, based on the autoregressive moving average (ARMA) innovation models and white noise estimation theory, using the optimal fusion rule weighted by diagonal matrices, a distributed descriptor Wiener state fuser is presented by weighting the local Wiener state estimators for the linear discrete stochastic descriptor systems with multisensor. It realizes a decoupled fusion estimation for state components. In order to compute the optimal weights, the formulas of computing the cross-covariances among local estimation errors are presented based on cross-covariances among the local innovation processes, input white noise, and measurement white noises. It can handle the fused filtering, smoothing, and prediction problems in a unified framework. Its accuracy is higher than that of each local estimator. A Monte Carlo simulation example shows its effectiveness and correctness. 展开更多
关键词 Multisensor information fusion Weighted fusion decoupled fusion Descriptor system Wiener statefuser White noise estimator ARMA innovation model Modern time series analysis method
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Decoupled estimation of frequency-dependent IQI and channel for OFDM systems with direct-conversion transceivers 被引量:1
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作者 Yan Liang Rongfang Song +2 位作者 Fei Li Xueyun He Lihua Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第3期435-441,共7页
The in-phase and quadrature-phase imbalance (IQI) is one of the major radio frequency impairments existing in orthogonal frequency division multiplexing (OFDM) systems with direct-conversion transceivers. During the t... The in-phase and quadrature-phase imbalance (IQI) is one of the major radio frequency impairments existing in orthogonal frequency division multiplexing (OFDM) systems with direct-conversion transceivers. During the transmission of the communication signal, the impact of IQI is coupled with channel impulse responses (CIR), which makes the traditional channel estimation schemes ineffective. A decoupled estimation scheme is proposed to separately estimate the frequency-dependent IQI and wireless channel. Firstly, the generalized channel model is built to separate the parameters of IQI and wireless channel. Then an iterative estimation scheme of frequency-dependent IQI is designed at the initial stage of communication. Finally, based on the estimation result of IQI, the least square algorithm is utilized to estimate the channel-related parameters at each time of channel variation. Compared with the joint estimation schemes of IQI and channel, the proposed decoupled estimation scheme requires much lower training overhead at each time of channel variation. Simulation results demonstrate the good estimation performance of the proposed scheme. 展开更多
关键词 direct-conversion transceivers frequency-dependent in-phase and quadrature-phase imbalance (IQI) orthogonal frequency division multiplexing (OFDM) decoupled estimation
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Decoupled Ce-Nd Isotopic Systematics of the Neoproterozoic Huangling Intrusive Complex and Its Geological Significance, Eastern Three Gorges, South China 被引量:1
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作者 Yongjuan Gao Wenli Ling +7 位作者 Xiaofei Qiu Ziwan Chen Shansong Lu Xiao Bai Xiujuan Bai Junbo Zhang Hongmei Yang Ruichun Duan 《Journal of Earth Science》 SCIE CAS CSCD 2016年第5期864-873,共10页
Cerium is one of multivalent rear earth elements, which can transfer from trivalence to tretavalence at oxidizing environment. This process may cause variable degrees of fractionation of Ce from other trivalent rear e... Cerium is one of multivalent rear earth elements, which can transfer from trivalence to tretavalence at oxidizing environment. This process may cause variable degrees of fractionation of Ce from other trivalent rear earth elements, and thus may provide specific insight into the geological processes associated with marked redoxomorphism. Multiple geochemical tracing of Sr-Nd-Ce isotopes are performed on the felsic and mafic intrusives of the Neoproterozoic(~800 Ma) Huangling complex located at the eastern Three Gorges, South China. The intrusive rocks exclusively show various extents of negative Ce anomalies. On the εCe-εNd plot, most samples from the mafic intrusions scatter within the second quadrant, whereas those from the felsic intrusions within the fourth Quadrant. Both of the two groups exhibit relatively large range of ?Ce(t) variation but limited ?Nd(t) range, which cause a deviation from the "crustal array" and reveal a decoupled Nd-Ce isotope correlation. The intermediate-felsic suite have varied Ce/Ce* ratios but broadly proximate εCe(t) values, indicating that their negative Ce anomalies were generated during the magmatism; on the contrary, a positive correlation between εCe(t) and Ce/Ce* is observed for the intermediate-mafic suite, an indication of an origin of post-magmatic alteration or metamorphism for their Ce anomalies. Calculation of model age, the occurrence age of negative Ce anomalies(TCe) for the intermediate-mafic samples infers that the alteration events took place 〉350 Ma. Data showed that negative Ce anomalies of the felsic intrusions may reflect an increase of oxygen fugacity during magma ascending, rather than an inheritance from their source rocks. This explanation implies that the Neoproterozoic magmatism occurred at the continental nucleus of the Yangtze block were developing at a geodynamic context of rapidly regional uplifting. 展开更多
关键词 negative Ce anomalies Ce-Nd isotopic decoupling ALTERATION oxidation environment.
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Understanding the Decoupled Effects of Cations and Anions Doping for High-Performance Perovskite Solar Cells 被引量:1
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作者 Tianxiang Hu Yixi Wang +16 位作者 Kai Liu Jia Liu Haoyang Zhang Qudrat Ullah Khan Shijie Dai Weifan Qian Ruochen Liu Yanyan Wang Chongyuan Li Zhenru Zhang Mingxiang Luo Xiaofei Yue Chunxiao Cong Yuan Yongbo Anran Yu Jia Zhang Yiqiang Zhan 《Nano-Micro Letters》 2025年第6期411-426,共16页
The past decade has witnessed the rapid increasement in power conversion efficiency of perovskite solar cells(PSCs).However,serious ion migration hampers their operational stability.Although dopants composed of varied... The past decade has witnessed the rapid increasement in power conversion efficiency of perovskite solar cells(PSCs).However,serious ion migration hampers their operational stability.Although dopants composed of varied cations and anions are introduced into perovskite to suppress ion migration,the impact of cations or anions is not individually explored,which hinders the evaluation of different cations and further application of doping strategy.Here we report that a special group of sulfonic anions(like CF_(3)SO_(3)^(-))successfully introduce alkaline earth ions(like Ca^(2+))into perovskite lattice compared to its halide counterparts.Furthermore,with effective crystallization regulation and defect passivation of sulfonic anions,perovskite with Ca(CF_(3)SO_(3))_(2)shows reduced PbI2 residue and metallic Pb0 defects;thereby,corresponding PSCs show an enhanced PCE of 24.95%.Finally by comparing the properties of perovskite with Ca(CF_(3)SO_(3))_(2)and FACF_(3)SO_(3),we found that doped Ca^(2+)significantly suppressed halide migration with an activation energy of 1.246 eV which accounts for the improved operational stability of Ca(CF_(3)SO_(3))_(2-)doped PSCs,while no obvious impact of Ca^(2+)on trap density is observed.Combining the benefits of cations and anions,this study presents an effective method to decouple the effects of cations and anions and fabricate efficient and stable PSCs. 展开更多
关键词 Perovskite solar cells Interstitial doping Effect decoupling Ion migration
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Tunable reflective spin-decoupled encoding metasurface based on Dirac semimetals
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作者 HAO Xiao-yu ZHENG Si-yu +6 位作者 WANG Yu LIU Yang LIU Meng ZHANG Yu-ping ZHANG Jin-juan ZHAN Yi ZHANG Hui-yun 《中国光学(中英文)》 北大核心 2025年第4期968-978,共11页
Multiple functional metasurfaces with high information capacity have attracted considerable attention from researchers.This study proposes a 2-bit tunable spin-decoupled coded metasurface designed for the terahertz ba... Multiple functional metasurfaces with high information capacity have attracted considerable attention from researchers.This study proposes a 2-bit tunable spin-decoupled coded metasurface designed for the terahertz band,which utilizes the tunable properties of Dirac semimetals(DSM)to create a novel multilayer structure.By incorporating both geometric and propagating phases into the metasurface design,we can effectively control the electromagnetic wave.When the Fermi level(EF)of the DSM is set at 6 meV,the electromagnetic wave is manipulated by the gold patch embedded in the DSM film,operating at a frequency of 1.3 THz.When the EF of the DSM is set at 80 meV,the electromagnetic wave is manipulated by the DSM patch,operating at a frequency of 1.4 THz.Both modes enable independent control of beam splitting under left-rotating circularly polarized(LCP)and rightrotating circularly polarized(RCP)wave excitation,resulting in the generation of vortex beams with distinct orbital angular momentum(OAM)modes.The findings of this study hold significant potential for enhancing information capacity and polarization multiplexing techniques in wireless communications. 展开更多
关键词 coding metasurface dirac semimetal spin decoupling circular polarization TUNABLE
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Simultaneous imposition of initial and boundary conditions via decoupled physics-informed neural networks for solving initialboundary value problems
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作者 K.A.LUONG M.A.WAHAB J.H.LEE 《Applied Mathematics and Mechanics(English Edition)》 2025年第4期763-780,共18页
Enforcing initial and boundary conditions(I/BCs)poses challenges in physics-informed neural networks(PINNs).Several PINN studies have gained significant achievements in developing techniques for imposing BCs in static... Enforcing initial and boundary conditions(I/BCs)poses challenges in physics-informed neural networks(PINNs).Several PINN studies have gained significant achievements in developing techniques for imposing BCs in static problems;however,the simultaneous enforcement of I/BCs in dynamic problems remains challenging.To overcome this limitation,a novel approach called decoupled physics-informed neural network(d PINN)is proposed in this work.The d PINN operates based on the core idea of converting a partial differential equation(PDE)to a system of ordinary differential equations(ODEs)via the space-time decoupled formulation.To this end,the latent solution is expressed in the form of a linear combination of approximation functions and coefficients,where approximation functions are admissible and coefficients are unknowns of time that must be solved.Subsequently,the system of ODEs is obtained by implementing the weighted-residual form of the original PDE over the spatial domain.A multi-network structure is used to parameterize the set of coefficient functions,and the loss function of d PINN is established based on minimizing the residuals of the gained ODEs.In this scheme,the decoupled formulation leads to the independent handling of I/BCs.Accordingly,the BCs are automatically satisfied based on suitable selections of admissible functions.Meanwhile,the original ICs are replaced by the Galerkin form of the ICs concerning unknown coefficients,and the neural network(NN)outputs are modified to satisfy the gained ICs.Several benchmark problems involving different types of PDEs and I/BCs are used to demonstrate the superior performance of d PINN compared with regular PINN in terms of solution accuracy and computational cost. 展开更多
关键词 decoupled physics-informed neural network(dPINN) decoupled formulation Galerkin method initial-boundary value problem(IBVP) machine learning
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Dual-branch spatial-temporal decoupled fusion transformer for safety action recognition in smart grid substation
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作者 HAO Yu ZHENG Hao +3 位作者 WANG Tongwen WANG Yu SUN Wei ZHANG Shujuan 《Optoelectronics Letters》 2025年第8期507-512,共6页
Smart grid substation operations often take place in hazardous environments and pose significant threats to the safety of power personnel.Relying solely on manual supervision can lead to inadequate oversight.In respon... Smart grid substation operations often take place in hazardous environments and pose significant threats to the safety of power personnel.Relying solely on manual supervision can lead to inadequate oversight.In response to the demand for technology to identify improper operations in substation work scenarios,this paper proposes a substation safety action recognition technology to avoid the misoperation and enhance the safety management.In general,this paper utilizes a dual-branch transformer network to extract spatial and temporal information from the video dataset of operational behaviors in complex substation environments.Firstly,in order to capture the spatial-temporal correlation of people's behaviors in smart grid substation,we devise a sparse attention module and a segmented linear attention module that are embedded into spatial branch transformer and temporal branch transformer respectively.To avoid the redundancy of spatial and temporal information,we fuse the temporal and spatial features using a tensor decomposition fusion module by a decoupled manner.Experimental results indicate that our proposed method accurately detects improper operational behaviors in substation work scenarios,outperforming other existing methods in terms of detection and recognition accuracy. 展开更多
关键词 identify improper operations manual supervision avoid misoperation spatial temporal substation safety action recognition technology dual branch decoupled fusion enhance safety managementin
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Multi-scale information fusion and decoupled representation learning for robust microbe-disease interaction prediction
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作者 Wentao Wang Qiaoying Yan +5 位作者 Qingquan Liao Xinyuan Jin Yinyin Gong Linlin Zhuo Xiangzheng Fu Dongsheng Cao 《Journal of Pharmaceutical Analysis》 2025年第8期1738-1752,共15页
Research indicates that microbe activity within the human body significantly influences health by being closely linked to various diseases.Accurately predicting microbe-disease interactions(MDIs)offers critical insigh... Research indicates that microbe activity within the human body significantly influences health by being closely linked to various diseases.Accurately predicting microbe-disease interactions(MDIs)offers critical insights for disease intervention and pharmaceutical research.Current advanced AI-based technologies automatically generate robust representations of microbes and diseases,enabling effective MDI predictions.However,these models continue to face significant challenges.A major issue is their reliance on complex feature extractors and classifiers,which substantially diminishes the models’generalizability.To address this,we introduce a novel graph autoencoder framework that utilizes decoupled representation learning and multi-scale information fusion strategies to efficiently infer potential MDIs.Initially,we randomly mask portions of the input microbe-disease graph based on Bernoulli distribution to boost self-supervised training and minimize noise-related performance degradation.Secondly,we employ decoupled representation learning technology,compelling the graph neural network(GNN)to independently learn the weights for each feature subspace,thus enhancing its expressive power.Finally,we implement multi-scale information fusion technology to amalgamate the multi-layer outputs of GNN,reducing information loss due to occlusion.Extensive experiments on public datasets demonstrate that our model significantly surpasses existing top MDI prediction models.This indicates that our model can accurately predict unknown MDIs and is likely to aid in disease discovery and precision pharmaceutical research.Code and data are accessible at:https://github.com/shmildsj/MDI-IFDRL. 展开更多
关键词 Microbe-disease interactions(MDIs) Pharmaceutical research AI-Based technologies decoupled representation learning Multi-scale information fusion
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Phase-modulated dynamical decoupling sequences robust to systematic amplitude error
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作者 Sijie Chen Guanxing Chen +3 位作者 Jiahao Huang Peiliang Liu Min Zhuang Chaohong Lee 《Chinese Physics B》 2025年第7期315-324,共10页
Dynamical decoupling(DD),usually implemented by sophisticated sequences of instantaneous control pulses,is a well-established quantum control technique for quantum information and quantum sensing.In practice,the pulse... Dynamical decoupling(DD),usually implemented by sophisticated sequences of instantaneous control pulses,is a well-established quantum control technique for quantum information and quantum sensing.In practice,the pulses are inevitably imperfect with many systematic errors that may influence the performances of DD.In particular,Rabi error and detuning are primary systemic errors arising from finite pulse duration,incorrect time control,and frequency instability.Here,we propose a phase-modulated DD with staggered global phases for the basic units of the pulse sequences to suppress these systemic errors.By varying the global phases appended to the pulses in the dynamical decoupling unit alternatively with 0 orπ,our protocol can significantly reduce the influences of Rabi error and detuning.Our protocol is general and can be combined with the most existing DD sequences such as universal DD,knill DD,XY,etc.As an example,we further apply our method to quantum lock-in detection for measuring time-dependent alternating signals.Our study paves the way for a simple and feasible way to realize robust dynamical decoupling sequences,which can be applicable for various quantum sensing scenarios. 展开更多
关键词 dynamical decoupling quantum sensing quantum lock-in amplifier
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The deflection angle and quasi-periodic oscillations of an extended gravitational decoupled black hole solution
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作者 Farzan Mushtaq Xia Tiecheng +2 位作者 Allah Ditta G Mustafa S K Maurya 《Communications in Theoretical Physics》 2025年第2期130-145,共16页
In weak field limits,we compute the deflection angle of a gravitational decoupling extended black hole(BH)solution.We obtained the Gaussian optical curvature by examining the null geodesic equations with the help of G... In weak field limits,we compute the deflection angle of a gravitational decoupling extended black hole(BH)solution.We obtained the Gaussian optical curvature by examining the null geodesic equations with the help of Gauss-Bonnet theorem(GBT).We also looked into the deflection angle of light by a black hole in weak field limits with the use of the Gibbons-Werner method.We verify the graphical behavior of the black hole after determining the deflection angle of light.Additionally,in the presence of the plasma medium,we also determine the deflection angle of the light and examine its graphical behavior.Furthermore,we compute the Einstein ring via gravitational decoupling extended black hole solution.We also compute the quasi-periodic oscillations and discuss their graphical behavior. 展开更多
关键词 deflection of light Gauss-Bonnet theorem gravitational decoupling
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A decoupled multi-objective optimization algorithm for cut order planning of multi-color garment
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作者 DONG Hui LYU Jinyang +3 位作者 LIN Wenjie WU Xiang WU Mincheng HUANG Guangpu 《High Technology Letters》 2025年第1期53-62,共10页
This work addresses the cut order planning(COP)problem for multi-color garment production,which is the first step in the clothing industry.First,a multi-objective optimization model of multicolor COP(MCOP)is establish... This work addresses the cut order planning(COP)problem for multi-color garment production,which is the first step in the clothing industry.First,a multi-objective optimization model of multicolor COP(MCOP)is established with production error and production cost as optimization objectives,combined with constraints such as the number of equipment and the number of layers.Second,a decoupled multi-objective optimization algorithm(DMOA)is proposed based on the linear programming decoupling strategy and non-dominated sorting in genetic algorithmsⅡ(NSGAII).The size-combination matrix and the fabric-layer matrix are decoupled to improve the accuracy of the algorithm.Meanwhile,an improved NSGAII algorithm is designed to obtain the optimal Pareto solution to the MCOP problem,thereby constructing a practical intelligent production optimization algorithm.Finally,the effectiveness and superiority of the proposed DMOA are verified through practical cases and comparative experiments,which can effectively optimize the production process for garment enterprises. 展开更多
关键词 multi-objective optimization non-dominated sorting in genetic algorithmsⅡ(NSGAII) cut order planning(COP) multi-color garment linear programming decoupling strategy
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From decoupled integrable models to coupled ones via a deformation algorithm
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作者 杜文鼎 孔德兴 楼森岳 《Communications in Theoretical Physics》 SCIE CAS CSCD 2023年第10期38-44,共7页
By using a reconstruction procedure of conservation laws of different models,the deformation algorithm proposed by Lou,Hao and Jia has been used to a new application such that a decoupled system becomes a coupled one.... By using a reconstruction procedure of conservation laws of different models,the deformation algorithm proposed by Lou,Hao and Jia has been used to a new application such that a decoupled system becomes a coupled one.Using the new application to some decoupled systems such as the decoupled dispersionless Korteweg–de Vries(Kd V)systems related to dispersionless waves,the decoupled KdV systems related to dispersion waves,the decoupled KdV and Burgers systems related to the linear dispersion and diffusion effects,and the decoupled KdV and Harry–Dym(HD)systems related to the linear and nonlinear dispersion effects,we have obtained various new types of higher dimensional integrable coupled systems.The new models can be used to describe the interactions among different nonlinear waves and/or different effects including the dispersionless waves(dispersionless KdV waves),the linear dispersion waves(KdV waves),the nonlinear dispersion waves(HD waves)and the diffusion effect.The method can be applied to couple all different separated integrable models. 展开更多
关键词 integrable systems deformation algorithm KdV equations higher dimensional integrable systems coupled and decoupled systems
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Periodical sparse-assisted decoupling method for local fault detection of spiral bevel gears
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作者 Keyuan LI Yanan WANG +2 位作者 Baijie QIAO Zhibin ZHAO Xuefeng CHEN 《Chinese Journal of Aeronautics》 2026年第1期349-369,共21页
Early fault detection for spiral bevel gears is crucial to ensure normal operation and prevent accidents.The harmonic components,excited by the time-varying mesh stiffness,always appear in measured vibration signal.Ho... Early fault detection for spiral bevel gears is crucial to ensure normal operation and prevent accidents.The harmonic components,excited by the time-varying mesh stiffness,always appear in measured vibration signal.How to extract the periodical impulses that indicate gear localized fault buried in the intensive noise and interfered by harmonics is a challenging task.In this paper,a novel Periodical Sparse-Assisted Decoupling(PSAD)method is proposed as an optimization problem to extract fault feature from noisy vibration signal.The PSAD method decouples the impulsive fault feature and harmonic components based on the sparse representation method.The sparsity within and across groups property and the periodicity of the fault feature are incorporated into the regularizer as the prior information.The nonconvex penalty is employed to highlight the sparsity of fault features.Meanwhile,the weight factor based on2norm of each group is constructed to strengthen the amplitude of fault feature.An iterative algorithm with Majorization-Minimization(MM)is derived to solve the optimization problem.Simulation study and experimental analysis confirm the performance of the proposed PSAD method in extracting and enhancing defect impulses from noisy signal.The suggested method surpasses other comparative methods in extracting and enhancing fault features. 展开更多
关键词 Fault detection Nonconvex optimization Sparse decoupling Sparsity within and across groups Spiral bevel gear
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Type Synthesis and Characteristic Analysis of a Family of 2-DOF Rotational Decoupled Parallel Mechanisms 被引量:14
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作者 ZENG Daxing Hou Yulei +1 位作者 HUANG Zhen LU Wenjuan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第6期833-840,共8页
It is widely used for the rotational parallel mechanism in the field of spatial orientation.While owing to the existence of coupling,the forward kinematic solution and the control of the general rotational parallel me... It is widely used for the rotational parallel mechanism in the field of spatial orientation.While owing to the existence of coupling,the forward kinematic solution and the control of the general rotational parallel mechanism are especially difficult.If decoupling can be realized,the kinematic analysis of the mechanism will be very simple.Presently,the research of the parallel mechanism is focused on the inverse solution and structure optimization,and there is a lack of rotation decoupled parallel mechanisms(DPMs).So this paper proposes a family of 2 degree of freedom(DOF)rotational DPMs based on the four-bar linkage mechanism,and performs a characteristic analysis.This family of DPMs is composed of a moving platform,a fixed base and three limbs.Taking U_RRU SPU DPM as an example,the motion feature of this DPM is analyzed with the constraint screw method,and its mobility is calculated by using the Modified Kutzbach-Grtibler criterion.The inverse and forward displacement problems of the proposed parallel mechanism are solved.The decoupled feature of the proposed parallel mechanism is validated by the deduction of the expression of the Jaeobian matrix.Three kinds of singularity conditions of this DPM are discussed,and the atlases of the output parameter concerning different geometric parameters are plotted with the theory of the physical model of the solution space.The proposition and characteristic analysis of the novel rotational DPMs in this paper should be useful for further research and application of the parallel mechanisms. 展开更多
关键词 parallel mechanism rotational decoupled constraint screw method ATLASES
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Comparative Analysis of Characteristics of the Coupled and Decoupled Parallel Mechanisms 被引量:18
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作者 ZENG Daxing HOU Yulei LU Wenjuan HUANG Zhen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第4期468-476,共9页
The existence of coupling makes the parallel mechanism possess some special advantages over the serial mechanism, while it is just the coupling that brings about the parallel mechanism some limitations, such as comple... The existence of coupling makes the parallel mechanism possess some special advantages over the serial mechanism, while it is just the coupling that brings about the parallel mechanism some limitations, such as complex workspace, high nonlinear relationship between input and output, difficulties in static and dynamic analysis, and the development of control system, which restricts its application fields. The decoupled parallel mechanism is currently one of the research focuses of the mechanism fields, while the study on the different characteristics between the deeoupled and coupled parallel mechanisms has not been reported. Therefore, this paper performs the systematic comparative analysis of the 3-RPUR and the 3-CPR parallel mechanisms. The features of the two mechanisms are described and their movement forms are analyzed with screw theory. The inverse and forward displacement solutions are solved and the Jacobian matrices are obtained. According to the Jacobian matrices and by using the theory of physical model of the solution space, the workspace, dexterity, velocity, payload capability, and stiffness of the mechanisms are analyzed with plotting the indices atlases. The research results prove that the effects of the coupling on the parallel mechanism are double-side, and then the adoption of the decoupled parallel mechanism should be determined by the requirements of the concrete application situation. The contents of this paper should be useful for the type synthesis and practical application of the parallel mechanism. 展开更多
关键词 parallel mechanism COUPLE decouple screw theory index atlas
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Design and Dynamic Modeling of a 2-DOF Decoupled Flexure-Based Mechanism 被引量:5
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作者 QIN Yanding TIAN Yanling ZHANG Dawei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第4期688-696,共9页
Flexure mechanisms with decoupled characteristics have been widely utilized in precision positioning applications.However,these mechanisms suffer from either slow response or low load capability.Furthermore,asymmetric... Flexure mechanisms with decoupled characteristics have been widely utilized in precision positioning applications.However,these mechanisms suffer from either slow response or low load capability.Furthermore,asymmetric design always leads to thermal error.In order to solve these issues,a novel 2-DOF decoupled mechanism is developed by monolithically manufacturing sets of statically indeterminate symmetric(SIS) flexure structures in parallel.Symmetric design helps to eliminate the thermal error and Finite Element Analysis(FEA) results show that the maximum coupling ratio between X and Y axes is below 0.25% when a maximum pretension force of 200 N is applied.By ignoring the mass effect,all the SIS flexure structures are simplified to "spring-damper" components,from which the static and dynamics model are derived.The relation between the first resonant frequency of the mechanism and the load is investigated by incorporating the load mass into the proposed dynamics model.Analytical results show that even with a load of 0.5 kg,the first resonant frequency is still higher than 300 Hz,indicating a high load capability.The mechanism's static and dynamic performances are experimentally examined.The linear stiffnesses of the mechanism at the working platform and at the driving point are measured to be 3.563 0 N·μm-1 and 3.362 1 N·μm-1,respectively.The corresponding estimation values from analytical models are 3.405 7 N·μm-1 and 3.381 7 N·μm-1,which correspond to estimation errors of-4.41% and 0.6%,respectively.With an additional load of 0.16 kg,the measured and estimated first resonant frequencies are 362 Hz and 365 Hz,respectively.The estimation error is only 0.55%.The analytical and experimental results show that the developed mechanism has good performances in both decoupling ability and load capability;its static and dynamic performance can be precisely estimated from corresponding analytical models.The proposed mechanism has wide potentials in precision positioning applications. 展开更多
关键词 precision positioning flexure hinge DYNAMICS decoupled structure
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