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Mitigating the Dynamic Load Altering Attack on Load Frequency Control with Network Parameter Regulation
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作者 Yunhao Yu Boda Zhang +4 位作者 Meiling Dizha Ruibin Wen Fuhua Luo Xiang Guo Zhenyong Zhang 《Computers, Materials & Continua》 2026年第2期1561-1579,共19页
Load frequency control(LFC)is a critical function to balance the power consumption and generation.Thegrid frequency is a crucial indicator for maintaining balance.However,the widely used information and communication ... Load frequency control(LFC)is a critical function to balance the power consumption and generation.Thegrid frequency is a crucial indicator for maintaining balance.However,the widely used information and communication infrastructure for LFC increases the risk of being attacked by malicious actors.The dynamic load altering attack(DLAA)is a typical attack that can destabilize the power system,causing the grid frequency to deviate fromits nominal value.Therefore,in this paper,we mathematically analyze the impact of DLAA on the stability of the grid frequency and propose the network parameter regulation(NPR)to mitigate the impact.To begin with,the dynamic LFC model is constructed by highlighting the importance of the network parameter.Then,we model the DLAA and analyze its impact on LFC using the theory of second-order dynamic systems.Finally,we model the NPR and prove its effect in mitigating the DLAA.Besides,we construct a least-effort NPR considering its infrastructure cost and aim to reduce the operation cost.Finally,we carry out extensive simulations to demonstrate the impact of the DLAA and evaluate the mitigation performance of NPR.The proposed cost-benefit NPR approach can not only mitigate the impact of DLAA with 100%and also save 41.18$/MWh in terms of the operation cost. 展开更多
关键词 Smart grid cybersecurity dynamic load altering attack load frequency control network parameter modification
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Dynamical analysis and nonlinear vibration control of integrated composite beam structure in thermal environment
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作者 Donghui LI Faming ZHANG +4 位作者 Qunfang LI Shang GAO Jian ZANG Yewei ZHANG Fengtian YANG 《Chinese Journal of Aeronautics》 2026年第1期278-300,共23页
Traditional dynamic analysis of mechanical structures,often limited to individual beams or plates,fails to fully capture their dynamic behaviors.In systems where space and mass are constrained,such as the battery supp... Traditional dynamic analysis of mechanical structures,often limited to individual beams or plates,fails to fully capture their dynamic behaviors.In systems where space and mass are constrained,such as the battery support structures in electric aircraft,conventional absorbers and isolators are insufficient for effective vibration control.This study simplifies the battery support structure of electric aircraft as an integrated composite beam consisting of three interconnected beams,and investigated its structural dynamics properties and nonlinear vibration control under thermal conditions caused by battery heat.The nonlinear vibration control is performed using the Nitinol steel wire ropes(Ni Ti-ST),with nonlinear damping properties.The natural frequencies of system are determined using the Rayleigh-Ritz technique.Theoretical results are validated through both Finite Element Method(FEM)and hammer tests.Moreover,the dynamic equations are derived using the Lagrange method and discretized via the Galerkin Truncation Method(GTM).The Harmonic Balance Method(HBM)is used to evaluate the vibration responses of the integrated model,with further verification through the Runge-Kutta Method(RKM).The experiments are conducted to corroborate the theoretical analysis.The results show that the system frequency changes in stages with the increase of the stiffness of the integrated composite beam connection.Especially in the case of varying environments,as the temperature increases,the frequency of system will first increase to a certain maximum value and then gradually decrease.Furthermore,the NiTi-ST effectively reduces vibration in the integrated composite beam,particularly under varying temperatures and external excitations. 展开更多
关键词 Composite laminated beam dynamics characteristic Integrated composite beam Modal experiment NiTiNOL steel wire rope Nonlinear vibration control
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Dynamic virtual power plants:A comprehensive review of architectures,control strategies,and grid support capabilities
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作者 Navid Vafamand Abbas Rabiee Innocent Kamwa 《iEnergy》 2026年第1期7-21,共15页
The increasing penetration of inverter-based resources(IBRs)and renewable energy resources poses significant challenges to the stability and controllability of modern power systems.Dynamic virtual power plants(DVPPs)h... The increasing penetration of inverter-based resources(IBRs)and renewable energy resources poses significant challenges to the stability and controllability of modern power systems.Dynamic virtual power plants(DVPPs)have emerged as a transformative solution for aggregating and controlling heterogeneously distributed energy resources(DERs)flexibly and dynamically.This paper presents a comprehensive review of DVPPs,covering their conceptual evolution—from microgrids to virtual power plants(VPPs)and fast-acting VPPs—culminating in the dynamic DVPP paradigm.This review explores key architectural frameworks,including grid-forming and grid-following roles,as well as AC/DC interfacing strategies.Emphasis is placed on secondary frequency and voltage control mechanisms,dynamic-based and market-based disaggregation,and control methodologies tailored to DERs. 展开更多
关键词 dynamic virtual power plants(DVPPs) Inverter-based resources(IBRs) Distributed energy resources(DERs) Disaggregation techniques control of DERs
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Dynamic Neural-Model-Based Predictive Control for Autonomous Wheel-Legged Robot System
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作者 Jiehao Li Junzheng Wang +2 位作者 Hongbo Gao Xiwen Luo C.L.Philip Chen 《CAAI Transactions on Intelligence Technology》 2026年第1期83-97,共15页
Mobile wheel-legged robots exhibiting mobility,stability and reliability have garnered heightened research attention in demanding real-world scenarios,especially in material transport,emergency response and space expl... Mobile wheel-legged robots exhibiting mobility,stability and reliability have garnered heightened research attention in demanding real-world scenarios,especially in material transport,emergency response and space exploration.The kinematics model merely delineates the geometric relationship of the controlled objective,disregarding force feedback.This study investigates model predictive trajectory tracking control utilising the robot dynamic model(DRMPC)in the context of unpredictable interactions.The predictive tracking controller for the wheel-legged robot is introduced in the context of position tracking.A dynamic approximator is employed to address the uncertain interactions in the tracking process.Ultimately,cosimulation and empirical tests are conducted to demonstrate the efficacy of the devised control methodology,which achieves high precision and dependable robustness.This work can elucidate the technical and practical oversight of autonomous movement in complicated environments and enhance the manoeuverability and flexibility. 展开更多
关键词 intelligent control predictive control ROBOTICS
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Impacts of Reactive Power Control Dynamics on Transient Stability of Grid-forming Converters Considering Current Saturation:Analysis and Enhancement
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作者 Jinming Xu Hanxu Diao +3 位作者 Zihan Ling Jiarong Kan Yunhu Luo Shaojun Xie 《CSEE Journal of Power and Energy Systems》 2026年第1期56-70,共15页
The transient synchronization stability of grid-forming converters(GFMCs)is significantly challenged under grid voltage sags.Continuous efforts have been devoted to analyzing the GFMC transient stability,with limited ... The transient synchronization stability of grid-forming converters(GFMCs)is significantly challenged under grid voltage sags.Continuous efforts have been devoted to analyzing the GFMC transient stability,with limited attention paid to the impacts of control loop dynamics.However,the complex control dynamics,especially the interactions between the active/reactive power control loops and the current saturation process(CSP),are crucial for accurately describing the transient behavior and evaluating the stability.Thus,in this study,a new large-signal GFMC model is established,considering the reactive power control(RPC)with different kinds of controllers and the CSP simultaneously.It is revealed that GFMC does not switch to the current-limited mode immediately,and the dynamics of RPC further affect the transient behavior before the current limiting significantly.Hence,the complex control dynamics can alter the mode switching point of current saturation,thereby increasing the risk of loss of synchronization(LOS).Based on the above findings,comprehensive comparisons of typical RPC controllers are presented to facilitate practical engineering applications.A unified stability enhancement method is proposed for solving the problem of LOS.Finally,experiments validate the correctness of the analysis and the effectiveness of the proposed control strategy. 展开更多
关键词 Current limit grid-forming converter reactive power control transient stability
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Nematode-fungus interactions in agriculture:Elucidating the dynamics of pathogenic and biocontrol relationships and their prospects
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作者 Lukman AHAMAD Sudeepta PATTANAYAK +4 位作者 Arshad KHAN Aasha RANA Syeda N.BEGUM Sanwei YANG Xin XIE 《Pedosphere》 2026年第1期186-199,共14页
Plant-parasitic nematodes(PPNs)(Meloidogyne sp.,Globodera sp.,and Pratylenchus sp.)and fungi are two of the most economically important groups of organisms affecting agricultural productivity worldwide.The interaction... Plant-parasitic nematodes(PPNs)(Meloidogyne sp.,Globodera sp.,and Pratylenchus sp.)and fungi are two of the most economically important groups of organisms affecting agricultural productivity worldwide.The interactions among PPNs,biocontrol fungi,and soil ecosystem can significantly impact plant health,disease management,and ecosystem functioning.We aimed to provide a comprehensive overview of the complex relationships between PPNs and biocontrol fungi,including pathogenic and biocontrol interactions.We summarized the molecular and ecological mechanisms underlying these interactions,highlighting the key players,signaling pathways,and environmental factors that influence the interactions.We also reviewed current knowledge on fungus-based biocontrol strategies against PPNs,including the development of novel management approaches.Furthermore,we explored the prospects of nematode-fungus interactions in agriculture,including the potential applications and technologies,precision agriculture,and integrated pest management approaches.This review highlights the need for further research on nematode-fungus interactions and their impact on plant infection and productivity,with an emphasis on the development of sustainable and effective strategies for managing PPNs and enhancing plant health in agricultural ecosystems. 展开更多
关键词 agricultural ecosystems biocontrol fungi biological control disease management pathogenic fungus plant health plant-parasitic nematodes
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Dynamic improvement and reliability enhancement of a high speed on/off valve based on pre-excitation soft switching control
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作者 Qi ZHONG Weihang ZHOU +3 位作者 Enguang XU Junxian WANG Xiaohang SHAN Huayong YANG 《Chinese Journal of Aeronautics》 2026年第2期582-592,共11页
High Speed on/off Valve(HSV)is an essential component in Aerospace Digital Hydraulic Systems(ADHS),which impose stringent requirements on the dynamic performance and reliability of HSV due to the extreme application e... High Speed on/off Valve(HSV)is an essential component in Aerospace Digital Hydraulic Systems(ADHS),which impose stringent requirements on the dynamic performance and reliability of HSV due to the extreme application environments.However,the faster dynamic leads to increased impact between the spool and valve body,causing severe vibration and wear,which creates a conflict between rapid dynamic and high reliability.To address this problem,a Pre-Excitation Soft Switching Control(PESSC)with both pre-excitation and reverse deceleration functionalities is proposed.The initial current is optimized through pre-excitation to accelerate the opening time,while the application of reverse voltage hastens the decline of electromagnetic force,thereby reducing the spool velocity.The PESSC simultaneously achieves both faster dynamic performance and smaller impact velocity.Moreover,the optimal deceleration voltage parameters are obtained through multi-objective optimization.Experimental results demonstrate that the optimized PESSC shortens the opening time from 2.22 ms to 1.65 ms,reduces the impact velocity by 58.3%,and lowers wear by 55.4%.These findings underline the huge potential of PESSC in enhancing the dynamic performance and reliability of HSVs,offering promising applications in aerospace. 展开更多
关键词 dynamic response High speed on/off valve Impact velocity Multi-objective optimization Pre-excitation Soft switching
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Coordination Thermodynamic Control of Magnetic Domain Configuration Evolution toward Low‑Frequency Electromagnetic Attenuation
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作者 Tong Huang Dan Wang +9 位作者 Xue He Zhaobo Feng Zhiqiang Xiong Yuqi Luo Yuhui Peng Guangsheng Luo Xuliang Nie Mingyue Yuan Chongbo Liu Renchao Che 《Nano-Micro Letters》 2026年第3期860-875,共16页
The precise tuning of magnetic nanoparticle size and magnetic domains,thereby shaping magnetic properties.However,the dynamic evolution mechanisms of magnetic domain configurations in relation to electromagnetic(EM)at... The precise tuning of magnetic nanoparticle size and magnetic domains,thereby shaping magnetic properties.However,the dynamic evolution mechanisms of magnetic domain configurations in relation to electromagnetic(EM)attenuation behavior remain poorly understood.To address this gap,a thermodynamically controlled periodic coordination strategy is proposed to achieve precise modulation of magnetic nanoparticle spacing.This approach unveils the evolution of magnetic domain configurations,progressing from individual to coupled and ultimately to crosslinked domain configurations.A unique magnetic coupling phenomenon surpasses the Snoek limit in low-frequency range,which is observed through micromagnetic simulation.The crosslinked magnetic configuration achieves effective low-frequency EM wave absorption at 3.68 GHz,encompassing nearly the entire C-band.This exceptional magnetic interaction significantly enhances radar camouflage and thermal insulation properties.Additionally,a robust gradient metamaterial design extends coverage across the full band(2–40 GHz),effectively mitigating the impact of EM pollution on human health and environment.This comprehensive study elucidates the evolution mechanisms of magnetic domain configurations,addresses gaps in dynamic magnetic modulation,and provides novel insights for the development of high-performance,low-frequency EM wave absorption materials. 展开更多
关键词 Thermodynamically controlled coordination strategy Magnetic domain configuration Low-frequency electromagnetic wave absorption Electrical/magnetic coupling MULTIFUNCTION
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Dynamics Modeling and Control of Vertical/Short Take-Off and Landing Aircraft During Take-Off and Landing Phases
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作者 Shiqiang Guo Xiaming Yuan Jihong Zhu 《Journal of Beijing Institute of Technology》 2026年第1期127-136,共10页
This paper proposes a trajectory tracking control scheme for vertical/short take-off and landing(V/STOL)vehicles.Owing to their high number of controllable degrees of freedom and strong nonlinearity,the design of flig... This paper proposes a trajectory tracking control scheme for vertical/short take-off and landing(V/STOL)vehicles.Owing to their high number of controllable degrees of freedom and strong nonlinearity,the design of flight control systems for such vehicles presents considerable challenges,particularly in developing controllers capable of accurately tracking specified trajectories.Building on existing control strategies for various vehicle types,this study introduces an extended control framework tailored for V/STOL systems.The proposed scheme consists of two nested loops:an outer position control loop and an inner attitude control loop.The position loop employs a proportional-integral-derivative(PID)control algorithm,whereas the attitude loop utilizes an anti-saturation integral sliding mode control algorithm.This approach effectively alleviates the integral oversaturation issue inherent in conventional sliding mode methods and suppresses buffeting through a boundary layer technique.Simulation results demonstrate the efficacy of the proposed control strategy. 展开更多
关键词 vertical/short take-off and landing(V/STOL) trajectory tracking integral sliding mode control
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Synthesis of Dynamic Virtual Impedance for Grid-forming Converters to Improve Self-stability and Stabilizing Ability
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作者 Hangyu Chen Verena Häberle +3 位作者 Ying Yang Kehao Zhuang Huanhai Xin Linbin Huang 《CSEE Journal of Power and Energy Systems》 2026年第1期44-55,共12页
In the future power-electronics-dominated power systems,grid-forming(GFM)converters have been regarded as important devices to actively establish frequency and voltage,so as to provide essential grid support.However,d... In the future power-electronics-dominated power systems,grid-forming(GFM)converters have been regarded as important devices to actively establish frequency and voltage,so as to provide essential grid support.However,due to their voltage source behavior and emulated swing dynamics,GFM converters may encounter low-frequency oscillations(LFOs)when connected to strong grids,which belongs to the self-stability problem of GFM converters.Moreover,GFM converters will also interact with grid-following(GFL)converters and thus impact the mid-frequency oscillations(MFOs)induced by phase-locked loops(PLLs).It has been preliminarily shown in the literature that GFM converters can help stabilize the PLL-induced MFOs,but currently,there is a lack of systematic design methods to coordinate the self-stability and stabilizing ability of GFM converters.This paper addresses this gap by revisiting the impedance model of a typical GFM converter and briefly analyze the oscillations caused by converters.Based on our analysis,we propose a frequency-partitioned synthesis design framework to enable dynamic virtual impedance(DVI)in GFM converters,aiming to enhance their self-stability and stabilizing ability simultaneously.Particularly,a self-stabilizing module is designed to ensure robust device-level damping,with control parameters auto-tuned using H∞methods.In parallel,a stabilizing module is introduced to stabilize GFL converters and enhance the system-level stability,which utilizes a perceive-and-optimize tuning strategy.Simulation results validate the effectiveness of the proposed synthesis DVI framework. 展开更多
关键词 control synthesis dynamic virtual impedance grid-forming converters self-stability stabilizing ability
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Hierarchical Demand Response Considering Dynamic Competing Interaction Based on Multi-agent Deep Deterministic Policy Gradient
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作者 Wenhao Wang Jiehui Zheng +3 位作者 Zhaoxi Liu Jiakun Fang Zhigang Li Q.H.Wu 《CSEE Journal of Power and Energy Systems》 2026年第1期162-174,共13页
To maximize the profits of power grid operators(GOs),load aggregators(LAs)and electricity customers(ECs),this paper proposes a hierarchical demand response(HDR)framework that considers competing interaction based on m... To maximize the profits of power grid operators(GOs),load aggregators(LAs)and electricity customers(ECs),this paper proposes a hierarchical demand response(HDR)framework that considers competing interaction based on multiagent deep deterministic policy gradient(MaDDPG).The ECs are divided into conventional ECs and the electric vehicles(EVs)which are managed by ECs agent(ECA)and EV agent(EVA)to exploit the flexibility of the HDR framework.Thus,the HDR is a tri-layer model determined by five types of agents engaging in competing interaction to maximize their own profits.To address the limitations of mathematical expression and participation scale in the Stackelberg game within the HDR model,a dynamic interaction mechanism is adopted.Moreover,to tackle the HDR involving various entities,the MaDDPG develops multiple agents to simulation the dynamic competing interactions between each subject as well as solve the problem of continuous action control.Furthermore,MaDDPG adopts soft target update and priority experience replay method to ensure stable and effective training,and makes the exploration strategy comprehensive by using exploration noise.Simulation studies are conducted to verify the performance of the MaDDPG with dynamic interaction mechanism in dealing with multilayer multi-agent continuous action control,compared to the double deep Q network(DDQN),deep Q network(DQN)and dueling DQN.Additionally,comparisons among the proposed HDR with the price based DR(PBDR)and incentive based DR(IBDR)are analyzed to investigate the flexibility of the HDR. 展开更多
关键词 Continuous action control deep reinforcement learning demand response dynamic interaction mechanism MULTI-AGENT
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Molecular Simulations of Dynamic Heterogeneity of Segment Motion and Bond Exchange in Polymer Vitrimers
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作者 Lang Shuai Jiang-Long Li +4 位作者 Jian-Long Wen Ying-Ying Xu Shui Yu Bo-Yu Ding Yi-Jing Nie 《Chinese Journal of Polymer Science》 2026年第1期242-255,I0017,共15页
Vitrimers belong to a class of polymeric materials capable of bond exchange reactions,showing great promise for environmental protection and sustainable development.However,studies on the coupling mechanism between th... Vitrimers belong to a class of polymeric materials capable of bond exchange reactions,showing great promise for environmental protection and sustainable development.However,studies on the coupling mechanism between the bond exchange kinetics and segmental dynamics near the glass transition temperature(T_(g))remain scarce.Herein,we employed molecular dynamics simulations to investigate the dynamic heterogeneity of the segment motion and bond exchange in vitrimers.The simulation results revealed that the bond exchange energy barrier exerts a much stronger influence on the bond exchange kinetics than on the segmental dynamics.At lower temperatures,slower segmental relaxation further constraind the bond exchange rate.Additionally,increasing the bond exchange energy barrier markedly enhanced the dynamic heterogeneity of segment motion.A close correlation was observed between heterogeneity and bond exchange.This study elucidated the coupling mechanism between bond exchange and segmental dynamics at the molecular scale,thereby providing a theoretical basis for designing vitrimer materials with tunable dynamic properties. 展开更多
关键词 Molecular dynamics simulations Vitrimers dynamic heterogeneity
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Fluid migration in calcite nanopores under salinity gradients:Insights from molecular dynamics
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作者 Yi Chen Yan Zhang +1 位作者 Run-Sheng Han Lei Wang 《Acta Geochimica》 2026年第1期185-203,共19页
The migration mechanisms of ore-forming fluids have long been a focus in the field of ore deposit studies.Calcite is ubiquitously present in various types of rocks in the lithosphere,and the underlying mechanisms of i... The migration mechanisms of ore-forming fluids have long been a focus in the field of ore deposit studies.Calcite is ubiquitously present in various types of rocks in the lithosphere,and the underlying mechanisms of its influence on fluid migration are of crucial importance.While previous studies have revealed that salinity changes can modulate fluid migration,the underlying mechanisms remain poorly understood.We employ molecular dynamics simulations to elucidate how salinity variations in ore-forming fluids modulate the adsorption onto calcite nanopore walls,thereby revealing the microscopic mechanisms governing ore fluid transport through calcite nano-fractures.The results show that the adsorption energy Eint of the solution on the calcite surface increased from -14,948.84±182.48 kcal/mol to -12,144.08±118.2 kcal/mol as salinity increased,which is conducive to the long-range transport of the fluid in the calcite nanopore. 展开更多
关键词 Fluid transport dynamics Salinity gradient regulation Calcite nanopores Molecular dynamics simulation
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From Static and Dynamic Perspectives:A Survey on Historical Data Benchmarks of Control Performance Monitoring 被引量:1
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作者 Pengyu Song Jie Wang +1 位作者 Chunhui Zhao Biao Huang 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期300-316,共17页
In recent decades,control performance monitoring(CPM)has experienced remarkable progress in research and industrial applications.While CPM research has been investigated using various benchmarks,the historical data be... In recent decades,control performance monitoring(CPM)has experienced remarkable progress in research and industrial applications.While CPM research has been investigated using various benchmarks,the historical data benchmark(HIS)has garnered the most attention due to its practicality and effectiveness.However,existing CPM reviews usually focus on the theoretical benchmark,and there is a lack of an in-depth review that thoroughly explores HIS-based methods.In this article,a comprehensive overview of HIS-based CPM is provided.First,we provide a novel static-dynamic perspective on data-level manifestations of control performance underlying typical controller capacities including regulation and servo:static and dynamic properties.The static property portrays time-independent variability in system output,and the dynamic property describes temporal behavior driven by closed-loop feedback.Accordingly,existing HIS-based CPM approaches and their intrinsic motivations are classified and analyzed from these two perspectives.Specifically,two mainstream solutions for CPM methods are summarized,including static analysis and dynamic analysis,which match data-driven techniques with actual controlling behavior.Furthermore,this paper also points out various opportunities and challenges faced in CPM for modern industry and provides promising directions in the context of artificial intelligence for inspiring future research. 展开更多
关键词 control performance monitoring(CPM) datadriven method historical data benchmark(HIS) industrial process performance index static and dynamic analysis.
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Short-chain Length Dependence of Equilibrium Dynamics and Nonlinear Rheology in Unentangled Long-chain/Short-chain Polymer Blends
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作者 Xiao-Yang Wang Bo Liu +2 位作者 Li-Jia An Zhen-Hua Wang Yu-Yuan Lu 《Chinese Journal of Polymer Science》 2026年第2期525-535,I0016,共12页
The equilibrium dynamics and nonlinear rheology of unentangled polymer blends remain inadequately understood,especially regarding the influence of short-chain matrix length N_(S) on the structure and rheological behav... The equilibrium dynamics and nonlinear rheology of unentangled polymer blends remain inadequately understood,especially regarding the influence of short-chain matrix length N_(S) on the structure and rheological behavior of dispersed long chains.Using molecular dynamics simulations based on the Kremer-Grest model,we systematically explore the N_(S)-dependence of static conformations,equilibrium dynamics,and nonlinear shear responses in unentangled long-chain/short-chain polymer blends.Our results demonstrate a decoupling between the static and dynamic sensitivity to N_(S):while the static chain size,R_g,follows Flory theory with slight swelling at small N_(S) due to incomplete excluded volume screening,the diffusion coefficient,D,and the relaxation time,τ_(0),exhibit a strong,non-monotonic N_(S)-dependence,transitioning from monomeric friction dominance at small N_(S) to collective segmental rearrangement at large N_(S).Additionally,we observe partial decoupling between the viscous and normal stress responses:while the zero-shear viscosity,η,is strongly N_(S)-dependent,the first and second normal stress coefficients,Ψ_(1) and Ψ_(2),collapse onto universal curves when scaled by the dimensionless shear rate,γτ_(0),suggesting a common mechanism of orientation and stretching.Under shear,long chains compress in the vorticity direction λ_(z)~Wi^(-0.2),which reduces collision frequency and contributes to shear thinning,while the scaling of weaker orientation resistance m_(G)~Wi^(0.35)reflects hydrodynamic screening by the short-chain matrix.These findings highlight the limitations of single-chain models and emphasize the necessity of considering N_(S)-dependent matrix dynamics and flow-induced structural changes in understanding the rheology of unentangled polymer blends. 展开更多
关键词 Unentangled polymer blend Nonlinear rheology Equilibrium dynamics Hydrodynamic interaction screening Molecular dynamics simulation
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MDGET-MER:Multi-Level Dynamic Gating and Emotion Transfer for Multi-Modal Emotion Recognition
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作者 Musheng Chen Qiang Wen +2 位作者 Xiaohong Qiu Junhua Wu Wenqing Fu 《Computers, Materials & Continua》 2026年第3期872-893,共22页
In multi-modal emotion recognition,excessive reliance on historical context often impedes the detection of emotional shifts,while modality heterogeneity and unimodal noise limit recognition performance.Existing method... In multi-modal emotion recognition,excessive reliance on historical context often impedes the detection of emotional shifts,while modality heterogeneity and unimodal noise limit recognition performance.Existing methods struggle to dynamically adjust cross-modal complementary strength to optimize fusion quality and lack effective mechanisms to model the dynamic evolution of emotions.To address these issues,we propose a multi-level dynamic gating and emotion transfer framework for multi-modal emotion recognition.A dynamic gating mechanism is applied across unimodal encoding,cross-modal alignment,and emotion transfer modeling,substantially improving noise robustness and feature alignment.First,we construct a unimodal encoder based on gated recurrent units and feature-selection gating to suppress intra-modal noise and enhance contextual representation.Second,we design a gated-attention crossmodal encoder that dynamically calibrates the complementary contributions of visual and audio modalities to the dominant textual features and eliminates redundant information.Finally,we introduce a gated enhanced emotion transfer module that explicitly models the temporal dependence of emotional evolution in dialogues via transfer gating and optimizes continuity modeling with a comparative learning loss.Experimental results demonstrate that the proposed method outperforms state-of-the-art models on the public MELD and IEMOCAP datasets. 展开更多
关键词 Multi-modal emotion recognition dynamic gating emotion transfer module cross-modal dynamic alignment noise robustness
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SSA*-PDWA:A Hierarchical Path Planning Framework with Enhanced A*Algorithm and Dynamic Window Approach for Mobile Robots
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作者 Lishu Qin Yu Gao Xinyuan Lu 《Computers, Materials & Continua》 2026年第4期2069-2094,共26页
With the rapid development of intelligent navigation technology,efficient and safe path planning for mobile robots has become a core requirement.To address the challenges of complex dynamic environments,this paper pro... With the rapid development of intelligent navigation technology,efficient and safe path planning for mobile robots has become a core requirement.To address the challenges of complex dynamic environments,this paper proposes an intelligent path planning framework based on grid map modeling.First,an improved Safe and Smooth A*(SSA*)algorithm is employed for global path planning.By incorporating obstacle expansion and cornerpoint optimization,the proposed SSA*enhances the safety and smoothness of the planned path.Then,a Partitioned Dynamic Window Approach(PDWA)is integrated for local planning,which is triggered when dynamic or sudden static obstacles appear,enabling real-time obstacle avoidance and path adjustment.A unified objective function is constructed,considering path length,safety,and smoothness comprehensively.Multiple simulation experiments are conducted on typical port grid maps.The results demonstrate that the improved SSA*significantly reduces the number of expanded nodes and computation time in static environmentswhile generating smoother and safer paths.Meanwhile,the PDWA exhibits strong real-time performance and robustness in dynamic scenarios,achieving shorter paths and lower planning times compared to other graph search algorithms.The proposedmethodmaintains stable performance across maps of different scales and various port scenarios,verifying its practicality and potential for wider application. 展开更多
关键词 dynamic window approach improved A*algorithm dynamic path planning trajectory optimization
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Dynamic behavior of steel post/wood panel railway noise barriers under aerodynamic loads induced by high-speed trains
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作者 Dongyun Liu Chao Wang +3 位作者 Jaime Gonzalez-Libreros Andréas Andersson Lennart Elfgren Gabriel Sas 《Railway Engineering Science》 2026年第1期55-84,共30页
Railway noise barriers are an essential piece of infrastructure for reducing noise propagation.However,these barriers experience aerodynamic loads generated by high-speed trains,leading to dynamic effects that may com... Railway noise barriers are an essential piece of infrastructure for reducing noise propagation.However,these barriers experience aerodynamic loads generated by high-speed trains,leading to dynamic effects that may compromise their fatigue capacity.The most common structural design for railway noise barriers consists of vertical configurations of posts and panels.However,there have been few dynamic analyses of steel post/wood panel noise barriers under train-induced aerodynamic loads.This study used dynamic finite element analysis to assess the dynamic behavior of such noise barriers.Analysis of a 40-m-long noise barrier model and a triangular simplified load model,the latter of which effectively represented the detailed aerodynamic load,were first used to establish the model and input of the moving load during dynamic simulation.Then,the effects of different parameters on the dynamic response of the noise barrier were evaluated,including the damping ratio,the profile of the steel post,the span length of the panel,the barrier height,and the train speed.Gray relational analysis indicated that barrier height exhibited the highest correlations with the dynamic responses,followed by train speed,post profile,span length,and damping ratio.A reduction in the natural frequency and an increase in the train speed result in a higher peak response and more pronounced fluctuations between the nose and tail waves.The dynamic amplification factor(DAF)was found to be related to both the natural frequency and train speed.A model was proposed showing that the DAF significantly increases as the square of the natural frequency decreases and the cube of the train speed rises. 展开更多
关键词 Aerodynamic load dynamic amplification factor dynamic behavior Finite element analysis High-speed train Railway noise barrier
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A Joint Optimization Model for Device Selection and Power Allocation under Dynamic Uncertain Environments
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作者 Bohui Li Bin Wang +2 位作者 Linjie Wu Xingjuan Cai Maoqing Zhang 《Computers, Materials & Continua》 2026年第2期1059-1086,共28页
Federated Learning(FL)provides an effective framework for efficient processing in vehicular edge computing.However,the dynamic and uncertain communication environment,along with the performance variations of vehicular... Federated Learning(FL)provides an effective framework for efficient processing in vehicular edge computing.However,the dynamic and uncertain communication environment,along with the performance variations of vehicular devices,affect the distribution and uploading processes of model parameters.In FL-assisted Internet of Vehicles(IoV)scenarios,challenges such as data heterogeneity,limited device resources,and unstable communication environments become increasingly prominent.These issues necessitate intelligent vehicle selection schemes to enhance training efficiency.Given this context,we propose a new scenario involving FL-assisted IoV systems under dynamic and uncertain communication conditions,and develop a dynamic interval multi-objective optimization algorithm to jointly optimize various factors including training experiments,system energy consumption,and bandwidth utilization to meet multi-criteria resource optimization requirements.For the problem at hand,we design a dynamic interval multi-objective optimization algorithm based on interval overlap detection.Simulation results demonstrate that our method outperforms other solutions in terms of accuracy,training cost,and server utilization.It effectively enhances training efficiency under wireless channel environments while rationally utilizing bandwidth resources,thus possessing significant scientific value and application potential in the field of IoV. 展开更多
关键词 Internet of vehicles edge computing dynamic uncertain environments device selection power allocation dynamic interval multi-objective algorithm
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Dynamic Behaviors of Localized Waves of the(2+1)-Dimensional Yu-Toda-Sasa-Fukuyama Equation
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作者 SUN Xiaoqing XIA Yarong +1 位作者 YAO Ruoxia WANG Weiqing 《应用数学》 北大核心 2026年第2期624-638,共15页
In this article,by employing the Hirota bilinear approach and the long wave limit method,we not only derive soliton solutions,lump solutions,and hybrid solutions for the(2+1)-dimensional Yu-Toda-Sasa-Fukuyama(YTSF)equ... In this article,by employing the Hirota bilinear approach and the long wave limit method,we not only derive soliton solutions,lump solutions,and hybrid solutions for the(2+1)-dimensional Yu-Toda-Sasa-Fukuyama(YTSF)equation,but also analyze the dynamical behaviors of nonlinear local wave propagation in shallow water.Firstly,based on the Hirota bilinear approach,one to four-order soliton solutions of the YTSF equation are obtained,and the effects of different parameters on the amplitude,propagation trajectory,and displacement of solitons are investigated.Secondly,using the long wave limit approach,one to three-order lump solutions and various physical quantities of the YTSF equation are derived.It is found that the real and imaginary parts of the parameter pi dominate the propagation trajectory and the shape of lump waves,respectively.Furthermore,we construct the hybrid solution for the YTSF equation,leading to the conclusion that the interaction between lumps and solitons constitutes an elastic collision.To intuitively understand the dynamic behaviors of these solutions,we conduct numerical simulations to present vivid three-dimensional visualizations. 展开更多
关键词 (2+1)-dimensional Yu-Toda-Sasa-Fukuyama equation Hirota bilinear approach Lump solutions dynamic behaviors
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