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SAD-YOLOv5:基于YOLOv5的铝合金表面缺陷检测方法
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作者 袁俊森 凌六一 《重庆工商大学学报(自然科学版)》 2025年第3期77-83,共7页
目的铝合金铸件表面缺陷检测是工业中的一个重要应用,正确且快速地检测出铸件表面的缺陷可以大大提高产量和质量。针对图像中缺陷目标较小,缺陷类别易混淆,定位不精准等问题,提出了一种在一级检测器基础上改进的SAD-YOLOv5模型。方法针... 目的铝合金铸件表面缺陷检测是工业中的一个重要应用,正确且快速地检测出铸件表面的缺陷可以大大提高产量和质量。针对图像中缺陷目标较小,缺陷类别易混淆,定位不精准等问题,提出了一种在一级检测器基础上改进的SAD-YOLOv5模型。方法针对一般卷积神经网络中由于跨步卷积和池化层导致网络训练过程中信息丢失的问题,通过引入空间到深度(space-to-depth,SPD)模块避免细粒度信息的丢失,提高对小目标的特征学习能力;为进一步提升网络模型精度,在网络的Head中引入自适应空间特征融合(adaptively spatial feature fusion,ASFF)和Decoupled Head,其中ASFF通过实现不同特征之间的自适应融合,抑制了不同尺度特征之间的不一致性,保留更有鉴别性的信息,从而提升网络学习能力;使用Decoupled Head替换原先的耦合头,将分类和回归进行解耦,使分类更加关注纹理信息,回归更加关注边缘信息,二者各司其职,进一步提升网络判断能力。结果在自己拍摄的铸件缺陷检测数据集中的测试结果表明,SAD-YOLOv5的mAP@0.5和mAP@0.5:0.95分别为95.1%和68%,较基线模型(YOLOv5)分别提升了1%和3.3%。结论SAD-YOLO5能更准确地完成铝合金铸件的表面缺陷检测任务。 展开更多
关键词 铝合金铸件 表面缺陷检测 YOLOv5 SPD ASFF Decoupled Head
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Two Second-Order Ecient Numerical Schemes for the Boussinesq Equations
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作者 LIU Fang WANG Danxia ZHANG Jianwen 《应用数学》 北大核心 2025年第1期114-129,共16页
In this paper,we construct two fully decoupled,second-order semi-discrete numerical schemes for the Boussinesq equations based on the scalar auxiliary variable(SAV)approach.By introducing a scalar auxiliary variable,t... In this paper,we construct two fully decoupled,second-order semi-discrete numerical schemes for the Boussinesq equations based on the scalar auxiliary variable(SAV)approach.By introducing a scalar auxiliary variable,the original Boussinesq system is transformed into an equivalent one.Then we discretize it using the second-order backward di erentiation formula(BDF2)and Crank-Nicolson(CN)to obtain two second-order time-advanced schemes.In both numerical schemes,a pressure-correction method is employed to decouple the velocity and pressure.These two schemes possess the desired property that they can be fully decoupled with satisfying unconditional stability.We rigorously prove both the unconditional stability and unique solvability of the discrete schemes.Furthermore,we provide detailed implementations of the decoupling procedures.Finally,various 2D numerical simulations are performed to verify the accuracy and energy stability of the proposed schemes. 展开更多
关键词 Scalar auxiliary variable approach Pressure-correction method Fully decoupled Unconditional stability Boussinesq equations
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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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Two Efficient Numerical Algorithms for the Thermally Coupled Incompressible MHD Equations
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作者 LIAO Mingliang WANG Danxia 《应用数学》 北大核心 2025年第4期932-951,共20页
In this work,we construct two efficient fully decoupled,linear,unconditionally stable numerical algorithms for the thermally coupled incompressible magnetohydrodynamic equations.Firstly,in order to obtain the desired ... In this work,we construct two efficient fully decoupled,linear,unconditionally stable numerical algorithms for the thermally coupled incompressible magnetohydrodynamic equations.Firstly,in order to obtain the desired algorithm,we introduce a scalar auxiliary variable(SAV)to get a new equivalent system.Secondly,by combining the pressure-correction method and the explicit-implicit method,we perform semi-discrete numerical algorithms of first and second order,respectively.Then,we prove that the obtained algorithms follow an unconditionally stable law in energy,and we provide a detailed implementation process,which we only need to solve a series of linear differential equations with constant coefficients at each time step.More importantly,with some powerful analysis,we give the order of convergence of the errors.Finally,to illustrate theoretical results,some numerical experiments are given. 展开更多
关键词 Magnetohydrodynamic equation Fully decoupled Unconditionally stability Scalar auxiliary variable Error analysis
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Error Analysis of MSAV Scheme for Two Phase Magnetohydrodynamic Diffuse Interface Model
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作者 HU Kun WANG Danxia +1 位作者 ZHANG Jianwen JIA Hongen 《应用数学》 北大核心 2025年第2期348-371,共24页
In this paper,we develop a multi-scalar auxiliary variables(MSAV)scheme for the Cahn-Hilliard Magnetohydrodynamics system by introducing two scalar auxiliary variables(SAV).This scheme is linear,fully decoupled and un... In this paper,we develop a multi-scalar auxiliary variables(MSAV)scheme for the Cahn-Hilliard Magnetohydrodynamics system by introducing two scalar auxiliary variables(SAV).This scheme is linear,fully decoupled and unconditionally stable in energy.Subsequently,we provide a detailed implementation procedure for full decoupling.Thus,at each time step,only a series of linear differential equations with constant coefficients need to be solved.To validate the effectiveness of our approach,we conduct an error analysis for this first-order scheme.Finally,some numerical experiments are provided to verify the energy dissipation of the system and the convergence of the proposed approach. 展开更多
关键词 Cahn-Hilliard Magnetohydrodynamics system Fully decoupled Stability in energy Error analysis
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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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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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Decouple the intermolecular interaction by encapsulating an insulating sheath
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作者 Saisai Yuan Yiming Chen +6 位作者 Xijuan Wang Degui Zhao Tengyang Gao Caiyun Wei Chuanxiang Chen Yang Yang Wenjing Hong 《Chinese Chemical Letters》 2025年第6期495-499,共5页
Single-molecule junctions are building blocks for constructing molecular devices.However,intermolecular interactions like winding bring additional interference among the surrounding molecules,which inhibits the intrin... Single-molecule junctions are building blocks for constructing molecular devices.However,intermolecular interactions like winding bring additional interference among the surrounding molecules,which inhibits the intrinsic coherent transport through single-molecule junctions.Here,we employed a nanocavity(dimethoxypillar[5]arene,DMP[5]),which is analogous to electric cables,to confine the conformation of flexible chains(1,8-diaminooctane,DAO)via host-vip interaction.Single-molecule conductance measurements indicate that the conductance of DAO encapsulated with DMP[5]is as high as that of pure DAO,as reproduced by theoretical simulations.Intriguingly,the molecular lengths of the DAO encapsulated with DMP[5]increase from 1.13 nm to 1.46 nm compared with the pure DAO,indicating that DMP[5]keeps DAO upright-standing via the confinement effect.This work provides a new strategy to decouple the intermolecular interaction by employing an insulating sheath,enabling the high-density integration of single-molecule devices. 展开更多
关键词 SINGLE-MOLECULE Molecule devices Host-vip interaction Confinement effect Decouple
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Accuracy and Consistency of the Explicit-Invariant Energy Quadratization Approach for the Cahn-Hilliard Equation
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作者 Jun ZHANG Fangying SONG Yu ZHANG 《Journal of Mathematical Research with Applications》 2025年第1期84-104,共21页
It is well known that the explicit-invariant energy quadratization(EIEQ)approach can generate fully decoupled,linear and unconditionally energy-stable numerical schemes,so it is favored by many researchers.However,the... It is well known that the explicit-invariant energy quadratization(EIEQ)approach can generate fully decoupled,linear and unconditionally energy-stable numerical schemes,so it is favored by many researchers.However,the undeniable fact is that the numerical method obtained by EIEQ approach preserves the“modified”energy law instead of the original energy.This is mainly due to the introduction of some auxiliary variables in EIEQ scheme,and the truncation error will make the auxiliary variables deviate from the original definition in the process of numerical calculation.The primary objective of this paper is to address this gap by providing the accuracy and consistency of the EIEQ method in the context of the CahnHilliard equation.We introduce a relaxation technique for auxiliary variables and construct two numerical schemes based on EIEQ.The analysis results show that the newly constructed schemes are not only unconditionally energy stable,linear and fully decoupled,but also can effectively correct the errors introduced by auxiliary variables and follow the original energy law.Finally,several 2D and 3D numerical examples illustrate the accuracy and efficiency of the newly constructed numerical schemes. 展开更多
关键词 Cahn-Hilliard equation EIEQ unconditionally energy stable fully decoupled Relaxation technique
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Decoupling control for tailless aircraft based fractional-order error extended state observer
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作者 Yunlong Hu Mingfei Zhao +2 位作者 Jia Song Wenling Li Yang Liu 《Control Theory and Technology》 2025年第3期397-409,共13页
The elimination of the vertical tail in tailless aircraft results in a significant decrease in heading static stability,causing substantial coupling among the three control channels.In addition,in specific operational... The elimination of the vertical tail in tailless aircraft results in a significant decrease in heading static stability,causing substantial coupling among the three control channels.In addition,in specific operational scenarios,the tailless aircraft is prone to electromagnetic interference,leading to the generation of high-frequency noise and consequently compromising their control performance.To address these issues,a decoupling control method based on a fractional-order error extended state observer(FOEESO)is proposed.A nonlinear model of a tailless aircraft with thrust vectoring capabilities is first developed.The decoupling control design for the three control channels is then implemented using FOEESO,with the asymptotic convergence conditions outlined.The proposed method is evaluated through simulations and compared to coupled control and linear extended state observer(LESO)techniques.Numerical simulations demonstrate that the FOEESO-based control methodology achieves effective decoupling,exhibiting 6.9%and 11.7%reductions in integral absolute error(IAE)relative to LESO under nominal operational conditions and critical fault scenarios,respectively.These improvements thereby highlight FOEESO’s capability to enhance closed-loop stability and tracking precision in tailless aircraft control systems. 展开更多
关键词 Tailless aircraft Decoupling control ADRC High-frequency noise
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WEAPONIZING TRADE, UNDERMINING TRUST The Trump administration’s politicization of global economics threatens international stability and damages China-U.S. relations
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作者 Hamzah Rifaat Hussain 《China Report ASEAN》 2025年第5期64-64,共1页
If there were any doubts about the Trump administration’s inherent obsession with decoupling,polarization and jolting of global trade,they can be laid to rest.A series of statements and measures have been made by the... If there were any doubts about the Trump administration’s inherent obsession with decoupling,polarization and jolting of global trade,they can be laid to rest.A series of statements and measures have been made by the U.S.government on economic relations with China including administrative decision to hit Chinese goods with additional tariffs despite China. 展开更多
关键词 global trade economic relations trade decoupling international stability tariffs polarization TRUST china u s relations
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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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Hysteresis compensation and decoupling control of an XYΘ-type flexure-based mechanism via inverse hysteresis-coupling hybrid modeling
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作者 Yanding Qin Jie Yuan +2 位作者 Yunpeng Zhang Hui Tang Jianda Han 《Nanotechnology and Precision Engineering》 2025年第2期1-12,共12页
Planar positioning systems are widely utilized in micro and nano applications.The challenges in modeling and control of XYΘflexure-based mechanisms include hysteresis of the piezoelectric actuators,couplings among th... Planar positioning systems are widely utilized in micro and nano applications.The challenges in modeling and control of XYΘflexure-based mechanisms include hysteresis of the piezoelectric actuators,couplings among the input axes,and coupled linear and angular motions of the end effector.This paper presents an inverse hysteresis-coupling hybrid model to account for such hysteresis and couplings.First,a specially designed kinematic chain is adopted to transfer the pose of the end effector into the linear motions at three prismatic joints.Second,an inverse hysteresis-coupling hybrid model is developed to linearize and decouple the system via a multilayer feedforward neural network.A fractional-order PID controller is also integrated to improve the motion accuracy of the overall system.Experimental results demonstrate that the proposed method can accurately control the motion of the end effector with improved accuracy and robustness. 展开更多
关键词 Flexure-based mechanism Micro-vision-aided measurement Hysteresis compensation Decoupling control
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Synergetic monitoring of pressure and temperature stimulations in multisensory electronic skin based on time decoupling effect
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作者 Zhiyi Gao Ye Zhang +10 位作者 Zhenyu Hu Dongdong Zhang Shengbin Li Huiyun Xiao Ziyin Xiang Dan Xu Haifeng Zhang Yuanzhao Wu Yiwei Liu Jie Shang Runwei Li 《Carbon Energy》 2025年第1期52-63,共12页
The progress from intelligent interactions requires electronic skin(E-skin)to shift from single-functional perception to multisensory capabilities.However,the intuitive and interference-free reading of multiple sensor... The progress from intelligent interactions requires electronic skin(E-skin)to shift from single-functional perception to multisensory capabilities.However,the intuitive and interference-free reading of multiple sensory signals without involving complex algorithms is a critical challenge.Herein,we propose a flexible multisensory E-skin by developing a highly homogeneous dispersion of BaTiO_(3)nanoparticles in polydimethylsiloxane dielectric layer.The E-skin is sensitive to externally applied pressure as well as temperature and can distinguish dual synergetic stimuli by the time decoupling effect.The pressure and temperature perception was achieved in an individual device,which greatly reduced the structural complexity compared with multifunctional integrated devices.The sensitivity of E-skin for pressure detection is as high as 0.0724 kPa^(−1)and the detection range reaches as wide as 15.625-10 MPa.The sensitivity to temperature detection is as high as−1.34℃^(−1)and the detection range reaches 20-200℃.More importantly,by equipping with a multilayer neural network,the evolution from tactile perception to advanced intelligent tactile cognition is demonstrated. 展开更多
关键词 E-skin intelligent tactile cognition machine learning multifunctional sensing time decoupling effect
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A High-Order Numerical Method Based on Legendre Polynomial Approximation for Fourth-Order Eigenvalue Problem in Cylinder Domain
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作者 Jun ZHANG Jihui ZHENG Fangying SONG 《Journal of Mathematical Research with Applications》 2025年第2期195-219,共25页
In this work, an efficient spectral method is proposed to solve the fourth-order eigenvalue problem in cylinder domain. Firstly, the key point of this method is to decompose the original model into a kind of decoupled... In this work, an efficient spectral method is proposed to solve the fourth-order eigenvalue problem in cylinder domain. Firstly, the key point of this method is to decompose the original model into a kind of decoupled two-dimensional eigenvalue problem by cylindrical coordinate transformation and Fourier series expansion, and deduce the crucial essential pole conditions. Secondly, we define a kind of weighted Sobolev spaces, and establish a suitable variational formula and its discrete form for each two-dimensional eigenvalue problem. Furthermore, we derive the equivalent operator formulas and obtain some prior error estimates of spectral theory of compact operators. More importantly, we further obtained error estimates for approximating eigenvalues and eigenfunctions by using two newly constructed projection operators. Finally,some numerical experiments are performed to validate our theoretical results and algorithm. 展开更多
关键词 fourth-order equation decoupled reduced-dimension formulation Legendre-Galerkin method error estimate cylinder domain
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Decoupling economic growth from industrial SO_(2)emissions in China:A two-stage decomposition approach
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作者 Yuanna Tian Yizhong Wang +3 位作者 Ye Hang Dequn Zhou Xiurong Hu Qunwei Wang 《Chinese Journal of Population,Resources and Environment》 2025年第1期49-61,共13页
Exploring the factors driving the decoupling of China’s sulfur dioxide(SO_(2))emissions from economic growth(DEI)is crucial for achieving sustainable development.By analyzing the decoupling indicators and driving fac... Exploring the factors driving the decoupling of China’s sulfur dioxide(SO_(2))emissions from economic growth(DEI)is crucial for achieving sustainable development.By analyzing the decoupling indicators and driving factors at both the generation and treatment stages of SO_(2),more effective targeted mitigation strategies can be developed.We employ the Tapio decoupling model and propose a two-stage method to examine the decoupling issues related to SO_(2).Our findings indicate that:①DEI shows a steady and significant improvement,with SO_(2)emission intensity identified as the primary driver.②for the decoupling of economic growth and SO_(2)generation,energy scale serves as the largest stimulator,while the effect of energy intensity changes from negative to positive,and pollution intensity is first positive and then negative.③For the decoupling of SO_(2)generation and SO_(2)removal,treatment efficiency leads as the largest promoter,followed by treatment intensity.Based on these results,this study recommends that China focuses more on enhancing clean energy utilization and the effectiveness of treatment processes. 展开更多
关键词 Driving factors Tapio decoupling indicator LMDI decomposition Two-stage method
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Minimally deformed anisotropic version of Tolman-Finch-Skea stellar model in Einstein-Gauss-Bonnet gravity
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作者 Hina Azmat Rafia Khalid +2 位作者 M Zubair Emre Demir Ertan Gudekli 《Communications in Theoretical Physics》 2025年第6期133-148,共16页
In this article,a well-known anisotropic solution,the Tolman-Finch-Skea(TFS)solution,is studied using the gravitational decoupling approach within the framework of 4D Einstein-Gauss-Bonnet(EGB)gravity.The radial metri... In this article,a well-known anisotropic solution,the Tolman-Finch-Skea(TFS)solution,is studied using the gravitational decoupling approach within the framework of 4D Einstein-Gauss-Bonnet(EGB)gravity.The radial metric potential is modified linearly through the minimal geometric deformation approach,while the temporal component of the metric remains unchanged.The system of EGB field equations is decomposed into two distinct sets of field equations:one corresponding to the standard energy-momentum tensor and the other associated with an external gravitational source.The first system is solved using the aforementioned known solution,while the second is closed by imposing the mimic constraint on pressure.Moreover,the junction conditions at the inner and outer surfaces of the stellar object are examined,considering the Boulware-Deser 4D space-time as the external geometry.The physical properties of the stellar model are analyzed using parameters such as energy conditions,causality conditions,compactness,and redshift. 展开更多
关键词 Einstein-Gauss-Bonnet gravity stellar model Tolman-Finch-Skea solution gravitational decoupling
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Factors Affecting CO_(2)Emissions from Direct Energy Household Consumption in Vietnam
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作者 Huu Nguyen Xuan Nguyen Valeriy Mikhailovich Koshelev 《Journal of Environmental & Earth Sciences》 2025年第3期178-194,共17页
The energy sector is pivotal in Vietnam’s commitment to achieving net-zero emissions by 2050.This study employs a combination of Structural Decomposition Analysis(SDA)and decoupling approaches based on data from Viet... The energy sector is pivotal in Vietnam’s commitment to achieving net-zero emissions by 2050.This study employs a combination of Structural Decomposition Analysis(SDA)and decoupling approaches based on data from Vietnam’s energy statistics and the Vietnam Living Standards Survey(VHLSS)for 2016,2018,and 2020.The primary aim is to elucidate the effects of direct energy consumption by household groups on CO_(2)emissions,examine factors affecting emissions,and clarify the relationship between CO_(2)emissions from household energy consumption and economic growth in Vietnam.Research results underscore that household groups make considerable use of electricity and Liquefied Petroleum Gas(LPG),simultaneously reducing the proportion of firewood,rice husk,sawdust,agricultural by-products and other fuels.The decrease in energy intensity emerges as the primary factor in lowering household emissions,while population growth and economic efficiency exert the opposite effect.Additionally,the research reveals disparities in emissions between urban and rural areas,similarly among household groups within the given location.Despite maintaining a robust decoupling status between emissions from household consumption and economic growth,unsustainable risks persist,particularly with the increase in electricity demand.The study also highlights the uneven impact of the COVID-19 epidemic on CO_(2)emissions across household groups.Drawing upon these findings,several recommendations are proposed to control CO_(2)emissions from direct energy household consumption to facilitate the most effective household decarbonisation process while ensuring sustainable economic growth in Vietnam. 展开更多
关键词 CO_(2)Emissions ENERGY Household Consumption SDA Decoupling Analysis COVID Epidemic Economic Growth VIETNAM
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Understanding the Decoupled Effects of Cations and Anions Doping for High-Performance Perovskite Solar Cells
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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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Multi-Objective optimization for stable and efficient cargo transportation of partial space elevator
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作者 Gefei Shi Zheng H.Zhu 《Defence Technology(防务技术)》 2025年第2期17-29,共13页
This paper proposed a new libration decoupling analytical speed function(LD-ASF)in lieu of the classic analytical speed function to control the climber's speed along a partial space elevator to improve libration s... This paper proposed a new libration decoupling analytical speed function(LD-ASF)in lieu of the classic analytical speed function to control the climber's speed along a partial space elevator to improve libration stability in cargo transportation.The LD-ASF is further optimized for payload transportation efficiency by a novel coordinate game theory to balance competing control objectives among payload transport speed,stable end body's libration,and overall control input via model predictive control.The transfer period is divided into several sections to reduce computational burden.The validity and efficacy of the proposed LD-ASF and coordinate game-based model predictive control are demonstrated by computer simulation.Numerical results reveal that the optimized LD-ASF results in higher transportation speed,stable end body's libration,lower thrust fuel consumption,and more flexible optimization space than the classic analytical speed function. 展开更多
关键词 Partial space elevator Stable transportation Libration decoupling analytical speed function Coordinate game Model predictive control Pareto optimization
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