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Clinical efficacy of Angong Jiangya pill (安宫降压丸) for grade 2 hypertension with liver-fire hyperactivity syndrome:a randomized,double-blind,placebo-controlled,multicenter trial
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作者 LAI Xiaolei SHANG Juju +4 位作者 LIU Hongxu HU Jing LI Xiang ZHANG Zhenmin XING Wenlong 《Journal of Traditional Chinese Medicine》 2025年第2期422-429,共8页
OBJECTIVE:To investigate the efficacy and safety of Angong Jiangya pill(AGJY,安宫降压丸)in the treatment of grade 2 hypertension with liver-fire hyperactivity syndrome.METHODS:This multicenter,randomized,double-blind,... OBJECTIVE:To investigate the efficacy and safety of Angong Jiangya pill(AGJY,安宫降压丸)in the treatment of grade 2 hypertension with liver-fire hyperactivity syndrome.METHODS:This multicenter,randomized,double-blind,placebo-controlled trial was conducted in eight medical institutions.Eligible patients with grade 2 hypertension were randomly allocated to receive AGJY or a placebo for 12 weeks.The primary outcome was the change in blood pressure(BP).The secondary outcomes were BP compliance rate,Traditional Chinese Medicine(TCM)symptoms,and Duchenne Hypertension Quality of Life Scale score.RESULTS:Data were analyzed for 117 participants in the AGJY group and 118 participants in the placebo group.After 12 weeks of treatment,AGJY compared with placebo resulted in a higher and significant reduction in systolic/diastolic BP(-15.58±10.16/-9.72±7.41 vs-8.13±8.28/-4.86±5.68 mm Hg,P<0.0001,<0.0001,respectively).BP compliance rate(31.86%vs 19.13%,P=0.027)was significantly higher in the AGJY group than in the placebo group.The AGJY group showed a significant reduction in TCM symptom score compared with the placebo group(10.82±2.03 vs 7.83±1.24,P<0.0001).Single TCM syndrome clinical control rates of the primary symptoms(dizziness,headache,and irritability)were superior in the AGJY group(71.95%,94.62%,72.53%,respectively)compared with the placebo group(48.39%,68.00%,30.52%,respectively).Scores on the Duchenne Hypertension Quality of Life Scale showed a significant increase in the AGJY group compared with the placebo group(30.65±21.06 vs 9.96±10.72,P=0.000).No serious adverse events occurred.CONCLUSION:AGJY demonstrated efficacy in lowering BP,increasing the rate of BP compliance,and improving TCM symptoms and quality of life in patients with grade 2 hypertension liver-fire hyperactivity syndrome.However,further in-depth studies are required to determine the mechanism of TCM in treating hypertension. 展开更多
关键词 HYPERTENSION multicenter study randomized controlled trial liver-fire hyperactivity syndrome Angong Jiangya
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PID Steering Control Method of Agricultural Robot Based on Fusion of Particle Swarm Optimization and Genetic Algorithm
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作者 ZHAO Longlian ZHANG Jiachuang +2 位作者 LI Mei DONG Zhicheng LI Junhui 《农业机械学报》 北大核心 2026年第1期358-367,共10页
Aiming to solve the steering instability and hysteresis of agricultural robots in the process of movement,a fusion PID control method of particle swarm optimization(PSO)and genetic algorithm(GA)was proposed.The fusion... Aiming to solve the steering instability and hysteresis of agricultural robots in the process of movement,a fusion PID control method of particle swarm optimization(PSO)and genetic algorithm(GA)was proposed.The fusion algorithm took advantage of the fast optimization ability of PSO to optimize the population screening link of GA.The Simulink simulation results showed that the convergence of the fitness function of the fusion algorithm was accelerated,the system response adjustment time was reduced,and the overshoot was almost zero.Then the algorithm was applied to the steering test of agricultural robot in various scenes.After modeling the steering system of agricultural robot,the steering test results in the unloaded suspended state showed that the PID control based on fusion algorithm reduced the rise time,response adjustment time and overshoot of the system,and improved the response speed and stability of the system,compared with the artificial trial and error PID control and the PID control based on GA.The actual road steering test results showed that the PID control response rise time based on the fusion algorithm was the shortest,about 4.43 s.When the target pulse number was set to 100,the actual mean value in the steady-state regulation stage was about 102.9,which was the closest to the target value among the three control methods,and the overshoot was reduced at the same time.The steering test results under various scene states showed that the PID control based on the proposed fusion algorithm had good anti-interference ability,it can adapt to the changes of environment and load and improve the performance of the control system.It was effective in the steering control of agricultural robot.This method can provide a reference for the precise steering control of other robots. 展开更多
关键词 agricultural robot steering PID control particle swarm optimization algorithm genetic algorithm
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A New Inversion-free Iterative Method for Solving the Nonlinear Matrix Equation and Its Application in Optimal Control
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作者 GAO Xiangyu XIE Weiwei ZHANG Lina 《应用数学》 北大核心 2026年第1期143-150,共8页
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ... In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method. 展开更多
关键词 Nonlinear matrix equation Maximal positive definite solution Inversion-free iterative method Optimal control
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Conceptual design and preliminary feasibility study of fluid‑driven suspended control rods for molten salt reactors
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作者 Jin‑Tong Cao Gui‑Feng Zhu +4 位作者 Chang‑Qing Yu Ya‑Fen Liu Yang Zou Rui Yan Hong‑Jie Xu 《Nuclear Science and Techniques》 2026年第1期225-243,共19页
Molten salt reactors,being the only reactor type among Generation Ⅳ advanced nuclear reactors that utilize liquid fuels,offer inherent safety,high-temperature,and low-pressure operation,as well as the capability for ... Molten salt reactors,being the only reactor type among Generation Ⅳ advanced nuclear reactors that utilize liquid fuels,offer inherent safety,high-temperature,and low-pressure operation,as well as the capability for online fuel reprocessing.However,the fuel-salt flow results in the decay of delayed neutron precursors(DNPs)outside the core,causing fluctuations in the effective delayed neutron fraction and consequently impacting the reactor reactivity.Particularly in accident scenarios—such as a combined pump shutdown and the inability to rapidly scram the reactor—the sole reliance on negative temperature feedback may cause a significant increase in core temperature,posing a threat to reactor safety.To address these problems,this paper introduces an innovative design for a passive fluid-driven suspended control rod(SCR)to dynamically compensate for reactivity fluctuations caused by DNPs flowing with the fuel.The control rod operates passively by leveraging the combined effects of gravity,buoyancy,and fluid dynamic forces,thereby eliminating the need for an external drive mechanism and enabling direct integration within the active region of the core.Using a 150 MWt thorium-based molten salt reactor as the reference design,we develop a mathematical model to systematically analyze the effects of key parameters—including the geometric dimensions and density of the SCR—on its performance.We examine its motion characteristics under different core flow conditions and assess its feasibility for the dynamic compensation of reactivity changes caused by fuel flow.The results of this study demonstrate that the SCR can effectively counteract reactivity fluctuations induced by fuel flow within molten salt reactors.A sensitivity analysis reveals that the SCR’s average density exerts a profound impact on its start-up flow threshold,channel flow rate,resistance to fuel density fluctuations,and response characteristics.This underscores the critical need to optimize this parameter.Moreover,by judiciously selecting the SCR’s length,number of deployed units,and the placement we can achieve the necessary reactivity control while maintaining a favorable balance between neutron economy and heat transfer performance.Ultimately,this paper provides an innovative solution for the passive reactivity control in molten salt reactors,offering significant potential for practical engineering applications. 展开更多
关键词 Molten salt reactor DNP flow-induced reactivity Passive control Suspended control rod
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Adaptive Grid-Interface Control for Power Coordination in Multi-Microgrid Energy Networks
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作者 Sk.A.Shezan 《Energy Engineering》 2026年第1期91-114,共24页
Modern power systems increasingly depend on interconnected microgrids to enhance reliability and renewable energy utilization.However,the high penetration of intermittent renewable sources often causes frequency devia... Modern power systems increasingly depend on interconnected microgrids to enhance reliability and renewable energy utilization.However,the high penetration of intermittent renewable sources often causes frequency deviations,voltage fluctuations,and poor reactive power coordination,posing serious challenges to grid stability.Conventional Interconnection FlowControllers(IFCs)primarily regulate active power flowand fail to effectively handle dynamic frequency variations or reactive power sharing in multi-microgrid networks.To overcome these limitations,this study proposes an enhanced Interconnection Flow Controller(e-IFC)that integrates frequency response balancing and an Interconnection Reactive Power Flow Controller(IRFC)within a unified adaptive control structure.The proposed e-IFC is implemented and analyzed in DIgSILENT PowerFactory to evaluate its performance under various grid disturbances,including frequency drops,load changes,and reactive power fluctuations.Simulation results reveal that the e-IFC achieves 27.4% higher active power sharing accuracy,19.6% lower reactive power deviation,and 18.2% improved frequency stability compared to the conventional IFC.The adaptive controller ensures seamless transitions between grid-connected and islanded modes and maintains stable operation even under communication delays and data noise.Overall,the proposed e-IFCsignificantly enhances active-reactive power coordination and dynamic stability in renewable-integrated multi-microgrid systems.Future research will focus on coupling the e-IFC with tertiary-level optimization frameworks and conducting hardware-in-the-loop validation to enable its application in large-scale smart microgrid environments. 展开更多
关键词 Active power flow control interconnection flow controller(IFC) frequency response micro grid stability reactive power management
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Robust Sensor—Less PR Controller Design for 15-PUC Multilevel Inverter Topology with Low Voltage Stress for Renewable Energy Applications
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作者 K.Naga Venkata Siva Damodhar Reddy +3 位作者 P.Krishna Murthy Kiran Kumar Pulamolu M.Dharani T.Venkatakrishnamoorthy 《Energy Engineering》 2026年第1期221-242,共22页
Conventional multilevel inverters often suffer from high harmonic distortion and increased design complexity due to the need for numerous power semiconductor components,particularly at elevated voltage levels.Addressi... Conventional multilevel inverters often suffer from high harmonic distortion and increased design complexity due to the need for numerous power semiconductor components,particularly at elevated voltage levels.Addressing these shortcomings,thiswork presents a robust 15-level PackedUCell(PUC)inverter topology designed for renewable energy and grid-connected applications.The proposed systemintegrates a sensor less proportional-resonant(PR)controller with an advanced carrier-based pulse width modulation scheme.This approach efficiently balances capacitor voltage,minimizes steady-state error,and strongly suppresses both zero and third-order harmonics resulting in reduced total harmonic distortion and enhanced voltage regulation.Additionally,a novel switching algorithm simplifies the design and implementation,further lowering voltage stress across switches.Extensive simulation results validate the performance under various resistive and resistive-inductive load conditions,demonstrating compliance with IEEE-519 THD standards and robust operation under dynamic changes.The proposed sensorless PR-controlled 15-PUC inverter thus offers a compelling,cost-effective solution for efficient power conversion in next-generation renewable energy systems. 展开更多
关键词 PUC packed U cell MLI multilevel inverter SLC sensorless controller PR proportional resonant controller PD phase disposition THD total harmonic distortion
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Distributed robust data-driven event-triggered control for QUAVs under stochastic disturbances
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作者 Chao Song Hao Li +2 位作者 Bo Li Jiacun Wang Chunwei Tian 《Defence Technology(防务技术)》 2026年第1期155-171,共17页
To address the issue of instability or even imbalance in the orientation and attitude control of quadrotor unmanned aerial vehicles(QUAVs)under random disturbances,this paper proposes a distributed antidisturbance dat... To address the issue of instability or even imbalance in the orientation and attitude control of quadrotor unmanned aerial vehicles(QUAVs)under random disturbances,this paper proposes a distributed antidisturbance data-driven event-triggered fusion control method,which achieves efficient fault diagnosis while suppressing random disturbances and mitigating communication conflicts within the QUAV swarm.First,the impact of random disturbances on the UAV swarm is analyzed,and a model for orientation and attitude control of QUAVs under stochastic perturbations is established,with the disturbance gain threshold determined.Second,a fault diagnosis system based on a high-gain observer is designed,constructing a fault gain criterion by integrating orientation and attitude information from QUAVs.Subsequently,a model-free dynamic linearization-based data modeling(MFDLDM)framework is developed using model-free adaptive control,which efficiently fits the nonlinear control model of the QUAV swarm while reducing temporal constraints on control data.On this basis,this paper constructs a distributed data-driven event-triggered controller based on the staggered communication mechanism,which consists of an equivalent QUAV controller and an event-triggered controller,and is able to reduce the communication conflicts while suppressing the influence of random interference.Finally,by incorporating random disturbances into the controller,comparative experiments and physical validations are conducted on the QUAV platforms,fully demonstrating the strong adaptability and robustness of the proposed distributed event-triggered fault-tolerant control system. 展开更多
关键词 DATA-DRIVEN QUAV control Fault diagnosis Event-triggered Non-conflicting communication
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A Coordinated Multi-Loop Control Strategy for Fault Ride-Through in Grid-Forming Converters
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作者 Zhuang Liu Mingwei Ren +1 位作者 Kai Shi Peifeng Xu 《Energy Engineering》 2026年第1期115-135,共21页
Grid-Forming(GFM)converters are prone to fault-induced overcurrent and power angle instability during grid fault-induced voltage sags.To address this,this paper develops a multi-loop coordinated fault ridethrough(FRT)... Grid-Forming(GFM)converters are prone to fault-induced overcurrent and power angle instability during grid fault-induced voltage sags.To address this,this paper develops a multi-loop coordinated fault ridethrough(FRT)control strategy based on a power outer loop and voltage-current inner loops,aiming to enhance the stability and current-limiting capability of GFM converters during grid fault conditions.During voltage sags,the GFM converter’s voltage source behavior is maintained by dynamically adjusting the reactive power reference to provide voltage support,thereby effectively suppressing the steady-state component of the fault current.To address the active power imbalance induced by voltage sags,a dynamic active power reference correction method based on apparent power is designed to mitigate power angle oscillations and limit transient current.Moreover,an adaptive virtual impedance loop is implemented to enhance dynamic transient current-limiting performance during the fault initiation phase.This approach improves the responsiveness of the inner loop and ensures safe system operation under various fault severities.Under asymmetric fault conditions,a negative-sequence reactive current compensation strategy is incorporated to further suppress negative-sequence voltage and improve voltage symmetry.The proposed control scheme enables coordinated operation of multiple control objectives,including voltage support,current suppression,and power angle stability,across different fault scenarios.Finally,MATLAB/Simulink simulation results validate the effectiveness of the proposed strategy,showcasing its superior performance in current limiting and power angle stability,thereby significantly enhancing the system’s fault ride-through capability. 展开更多
关键词 Grid-forming converter multi-loop coordination negative-sequence control fault ride-through
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Hydrochemical characteristics,evolution,and controlling factors of a karstic river with reservoirs:Insights from spatial-temporal analysis
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作者 Jiang Wu Ting Wang +4 位作者 Tang Liu Jia-Ju Liu Nan Xu Hui Zeng Ling-Yan He 《Journal of Environmental Sciences》 2026年第1期108-119,共12页
Understanding water chemistry in karst regions is crucial for improving global water resource management and deepening our knowledge of the biogeochemical cycles shaping these sensitive environments.Despite advance-me... Understanding water chemistry in karst regions is crucial for improving global water resource management and deepening our knowledge of the biogeochemical cycles shaping these sensitive environments.Despite advance-ments in karst hydrology,significant gaps remain in long-term trends,underlying processes,and quantitative effects of environmental changes.This is especially true in areas like the Wujiang River(WJ)in China,where human activities such as reservoir construction and land use/cover changes have accelerated hydrochemical changes.We combined recent and historical monitoring data to provide a detailed analysis of the spatial and temporal characteristics,evolution,and controlling factors of major ions in WJ.These findings are important for local water management and contribute to global efforts to manage similar karst systems facing human-induced pressures.Our research shows clear seasonal differences in solute concentrations,with higher levels during the dry season.WJ’s water is rich in calcium,with Ca-HCO_(3) ion pairs being the most common.Reservoir monitor-ing stations show much higher levels of NO_(3)^(−)and SO_(4)^(2−)compared to river-type stations,likely due to longer hydraulic retention time and increased acid deposition.The study confirms the significant role of pH and water temperature in rock weathering processes.Land use/cover changes were identified as the primary drivers of solute variations(46.37%),followed by lithology(13.92%)and temperature(8.35%).Over the past two decades,in-tense carbonate weathering has been observed,especially during wet seasons.Among karstic provinces,Guizhou Province stands out with the highest ion concentrations,indicative of its extensive karst coverage and heightened weathering processes. 展开更多
关键词 Wujiang river Karst Reservoir Major ion controlling factor
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Coordinated Source-Network-Storage Inertia Control Strategy Based on Wind Power Transmission via MMC-HVDC System
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作者 Mengxuan Shi Lintao Li +3 位作者 Dejun Shao Xiaojie Pan Xingyu Shi Yuxun Wang 《Energy Engineering》 2026年第1期493-510,共18页
In wind power transmission via modular multilevel converter based high voltage direct current(MMCHVDC)systems,under traditional control strategies,MMC-HVDCcannot provide inertia support to the receiving-end grid(REG)d... In wind power transmission via modular multilevel converter based high voltage direct current(MMCHVDC)systems,under traditional control strategies,MMC-HVDCcannot provide inertia support to the receiving-end grid(REG)during disturbances.Moreover,due to the frequency decoupling between the two ends of the MMCHVDC,the sending-end wind farm(SEWF)cannot obtain the frequency variation information of the REG to provide inertia response.Therefore,this paper proposes a novel coordinated source-network-storage inertia control strategy based on wind power transmission via MMC-HVDC system.First,the grid-side MMC station(GS-MMC)maps the frequency variations of the REG to direct current(DC)voltage variations through the frequency mapping control,and uses submodule capacitor energy to provide inertial power.Then,the wind farm-side MMC station(WF-MMC)restores the DC voltage variations to frequency variations through the frequency restoration control and power loss compensation,providing real-time frequency information for the wind farm.Finally,based on real-time frequency information,thewind farmutilizes the rotor kinetic energy and energy storage to provide fast and lasting power support through the wind-storage coordinated inertia control strategy.Meanwhile,when the wind turbines withdraw from the inertia response phase,the energy storage can increase the power output to compensate for the power deficit,preventing secondary frequency drops.Furthermore,this paper uses small-signal analysis to determine the appropriate values for the key parameters of the proposed control strategy.A simulation model of the wind power transmission via MMCHVDC system is built in MATLAB/Simulink environment to validate and evaluate the proposed method.The results show that the proposed coordinated control strategy can effectively improve the system inertia level and avoid the secondary frequency drop under the load sudden increase condition. 展开更多
关键词 Wind and storage coordination modular multilevel converter inertia response coordinated control
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Virtual Synchronous Generator Control Strategy Based on Parameter Self-Tuning
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作者 Jin Lin BinYu +3 位作者 Chao Chen Jiezhen Cai Yifan Wu Cunping Wang 《Energy Engineering》 2026年第1期181-203,共23页
With the increasing integration of renewable energy,microgrids are increasingly facing stability challenges,primarily due to the lack of inherent inertia in inverter-dominated systems,which is traditionally provided b... With the increasing integration of renewable energy,microgrids are increasingly facing stability challenges,primarily due to the lack of inherent inertia in inverter-dominated systems,which is traditionally provided by synchronous generators.To address this critical issue,Virtual Synchronous Generator(VSG)technology has emerged as a highly promising solution by emulating the inertia and damping characteristics of conventional synchronous generators.To enhance the operational efficiency of virtual synchronous generators(VSGs),this study employs smallsignal modeling analysis,root locus methods,and synchronous generator power-angle characteristic analysis to comprehensively evaluate how virtual inertia and damping coefficients affect frequency stability and power output during transient processes.Based on these analyses,an adaptive control strategy is proposed:increasing the virtual inertia when the rotor angular velocity undergoes rapid changes,while strengthening the damping coefficient when the speed deviation exceeds a certain threshold to suppress angular velocity oscillations.To validate the effectiveness of the proposed method,a grid-connected VSG simulation platform was developed inMATLAB/Simulink.Comparative simulations demonstrate that the proposed adaptive control strategy outperforms conventional VSGmethods by significantly reducing grid frequency deviations and shortening active power response time during active power command changes and load disturbances.This approach enhances microgrid stability and dynamic performance,confirming its viability for renewable-dominant power systems.Future work should focus on experimental validation and real-world parameter optimization,while further exploring the strategy’s effectiveness in improvingVSG low-voltage ride-through(LVRT)capability and power-sharing applications in multi-parallel configurations. 展开更多
关键词 New power system grid-connected inverter virtual synchronous generator(VSG) virtual inertia damping coefficient adaptive control
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Diverse methods and practical aspects in controlling single semiconductor qubits:a review
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作者 Jia-Ao Peng Chu-Dan Qiu +1 位作者 Wen-Long Ma Jun-Wei Luo 《Journal of Semiconductors》 2026年第1期6-22,共17页
Quantum control allows a wide range of quantum operations employed in molecular physics,nuclear magnetic resonance and quantum information processing.Thanks to the existing microelectronics industry,semiconducting qub... Quantum control allows a wide range of quantum operations employed in molecular physics,nuclear magnetic resonance and quantum information processing.Thanks to the existing microelectronics industry,semiconducting qubits,where quantum information is encoded in spin or charge degree freedom of electrons or nuclei in semiconductor quantum dots,constitute a highly competitive candidate for scalable solid-state quantum technologies.In quantum information processing,advanced control techniques are needed to realize quantum manipulations with both high precision and noise resilience.In this review,we first introduce the basics of various widely-used control methods,including resonant excitation,adabatic passage,shortcuts to adiabaticity,composite pulses,and quantum optimal control.Then we review the practical aspects in applying these methods to realize accurate and robust quantum gates for single semiconductor qubits,such as Loss–DiVincenzo spin qubit,spinglet-triplet qubit,exchange-only qubit and charge qubit. 展开更多
关键词 quantum information with solid state qubits quantum control quantum dots quantum gate
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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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Construction of MMC-CLCC Hybrid DC Transmission System and Its Power Flow Reversal Control Strategy
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作者 Yechun Xin Xinyuan Zhao +3 位作者 Dong Ding Shuyu Chen Chuanjie Wang Tuo Wang 《Energy Engineering》 2026年第1期460-474,共15页
To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current(HVDC)links and multi-infeed DC systems in load-center regions,this paper proposes a hyb... To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current(HVDC)links and multi-infeed DC systems in load-center regions,this paper proposes a hybrid modular multilevel converter–capacitor-commutated line-commutated converter(MMC-CLCC)HVDC transmission system and its corresponding control strategy.First,the system topology is constructed,and a submodule configuration method for the MMC—combining full-bridge submodules(FBSMs)and half-bridge submodules(HBSMs)—is proposed to enable direct power flow reversal.Second,a hierarchical control strategy is introduced,includingMMCvoltage control,CLCC current control,and a coordinationmechanism,along with the derivation of the hybrid system’s power flow reversal characteristics.Third,leveraging the CLCC’s fast current regulation and theMMC’s negative voltage control capability,a coordinated power flow reversal control strategy is developed.Finally,an 800 kV MMC-CLCC hybrid HVDC system is modeled in PSCAD/EMTDC to validate the power flow reversal performance under a high proportion of full-bridge submodule configuration.Results demonstrate that the proposed control strategy enables rapid(1-s transition)and smooth switching of bidirectional power flow without modifying the structure of primary equipment:the transient fluctuation ofDC voltage from the rated value(UdcN)to themaximumreverse voltage(-kUdcN)is less than 5%;the DC current strictly follows the preset characteristic curve with a deviation of≤3%;the active power reverses continuously,and the system maintains stable operation throughout the reversal process. 展开更多
关键词 Hybrid HVDC transmission modular multilevel converter(MMC) controllable line commutated converter(CLCC) online power flow reversal full-bridge and half-bridge submodules new energy through dc transmission system
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Application of Large-Scale Systems Theory in Fire Control Systems
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作者 史天运 何广存 《Journal of Beijing Institute of Technology》 EI CAS 1995年第1期21+17-21,共6页
According the to the model of single tank fire control system, this paper makes use of decomposition-coordination theory of large-scale systems to discuss the shooting problem of multiple tank the control systems, and... According the to the model of single tank fire control system, this paper makes use of decomposition-coordination theory of large-scale systems to discuss the shooting problem of multiple tank the control systems, and alalyzes specifically the three-tank the control systems and models.the process was imitated in computer, and the optimal shooting element of 3TS system was got. In addition, probability of hitting the target was calculated. 展开更多
关键词 large-scale systems fire control systems coordination/shooting error probability of hitting the target
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Fire-needle acupuncture for upper limb spastic paralysis after stroke:Study protocol for a randomized controlled trial 被引量:12
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作者 Xin-yu Yue Zhuo-qi Feng +3 位作者 Xi-yi Yu Jia-min Hu Xiao-Jing He Shi Shu 《Journal of Integrative Medicine》 SCIE CAS CSCD 2019年第3期167-172,共6页
Background: Fire-needle acupuncture, an important kind of acupuncture therapy, has been clinically used to treat upper limb spastic paralysis(ULSP) after stroke. Clinical experience has indicated that fire-needle acup... Background: Fire-needle acupuncture, an important kind of acupuncture therapy, has been clinically used to treat upper limb spastic paralysis(ULSP) after stroke. Clinical experience has indicated that fire-needle acupuncture treatment takes less time, requires fewer visits, and has more rapid results and fewer side effects compared to chemical medicine alternatives. This study will evaluate the effects of fire-needle acupuncture for ULSP in the context of standardized clinical research and provide high-quality data to inform clinical procedures and future study design.Methods/Design: A randomized controlled trial will be carried out to evaluate the effects of fire-needle acupuncture therapy in patients with ULSP from stroke. ULSP patients(n = 120) will be recruited at Changhai Hospital in Shanghai, China. Patients will be randomly divided into three groups, including fire-needle acupuncture group(FAG), filiform-needle acupuncture group(FFAG) and rehabilitation treatment group(RTG). During the 3-week treatment, the FAG will be treated every two days, while FFAG and RTG will be treated 5 d in a row and then rest for 2 d. The Simplified Fugl-Meyer Motor Function Scale and Modified Ashworth Scale will be used as the primary outcome measures. Statistical analysis will be conducted by an independent statistician.Discussion: Through this study, the utility of fire-needle acupuncture in treating ULSP after stroke will be tested, and some specific claims of fire-needle acupuncture therapy will be evaluated, such as relieving spasm and muscular tension, improving activities of daily living, rapidity of response and less frequency of treatment compared with other treatments. 展开更多
关键词 fire-needle ACUPUNCTURE Upper limb SPASTIC PARALYSIS STROKE Randomized controlled trial Study protocol
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Design of a Proportional-Integral-Derivative Controller for an Automatic Generation Control of Multi-area Power Thermal Systems Using Firefly Algorithm 被引量:8
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作者 K.Jagatheesan B.Anand +3 位作者 Sourav Samanta Nilanjan Dey Amira S.Ashour Valentina E.Balas 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第2期503-515,共13页
Essentially, it is significant to supply the consumer with reliable and sufficient power. Since, power quality is measured by the consistency in frequency and power flow between control areas. Thus, in a power system ... Essentially, it is significant to supply the consumer with reliable and sufficient power. Since, power quality is measured by the consistency in frequency and power flow between control areas. Thus, in a power system operation and control,automatic generation control(AGC) plays a crucial role. In this paper, multi-area(Five areas: area 1, area 2, area 3, area 4 and area 5) reheat thermal power systems are considered with proportional-integral-derivative(PID) controller as a supplementary controller. Each area in the investigated power system is equipped with appropriate governor unit, turbine with reheater unit, generator and speed regulator unit. The PID controller parameters are optimized by considering nature bio-inspired firefly algorithm(FFA). The experimental results demonstrated the comparison of the proposed system performance(FFA-PID)with optimized PID controller based genetic algorithm(GAPID) and particle swarm optimization(PSO) technique(PSOPID) for the same investigated power system. The results proved the efficiency of employing the integral time absolute error(ITAE) cost function with one percent step load perturbation(1 % SLP) in area 1. The proposed system based FFA achieved the least settling time compared to using the GA or the PSO algorithms, while, it attained good results with respect to the peak overshoot/undershoot. In addition, the FFA performance is improved with the increased number of iterations which outperformed the other optimization algorithms based controller. 展开更多
关键词 Automatic generation control(AGC) fireFLY ALGORITHM GENETIC algorithm(GA) particle SWARM optimization(PSO) proportional-integral-derivative(PID) controller
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Multi-model Predictive Control of Ultra-supercritical Coal-fired Power Unit 被引量:6
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作者 王国良 阎威武 +2 位作者 陈世和 张曦 邵惠鹤 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第7期782-787,共6页
The control of ultra-supercritical(USC) power unit is a difficult issue for its characteristic of the nonlinearity, large dead time and coupling of the unit. In this paper, model predictive control(MPC) based on multi... The control of ultra-supercritical(USC) power unit is a difficult issue for its characteristic of the nonlinearity, large dead time and coupling of the unit. In this paper, model predictive control(MPC) based on multi-model and double layered optimization is introduced for coordinated control of USC unit. The linear programming(LP) combined with quadratic programming(QP) is used in steady optimization for computation of the ideal value of dynamic optimization. Three inputs(i.e. valve opening, coal flow and feedwater flow) are employed to control three outputs(i.e. load, main steam temperature and main steam pressure). The step response models for the dynamic matrix control(DMC) are constructed using the three inputs and the three outputs. Piecewise models are built at selected operation points. Double-layered multi-model predictive controller is implemented in simulation with satisfactory performance. 展开更多
关键词 Ultra-supercritical power unit Coordinated control Multi-model constrained predictive control
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Sliding Mode Predictive Control of Main Steam Pressure in Coal-fired Power Plant Boiler 被引量:4
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作者 史元浩 王景成 章云锋 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第6期1107-1112,共6页
Since the combustion system of coal-fired boiler in thermal power plant is characterized as time varying, strongly coupled, and nonlinear, it is hard to achieve a satisfactory performance by the conventional proportio... Since the combustion system of coal-fired boiler in thermal power plant is characterized as time varying, strongly coupled, and nonlinear, it is hard to achieve a satisfactory performance by the conventional proportional integral derivative (PID) control scheme. For the characteristics of the main steam pressure in coal-fired power plant boiler, the sliding mode control system with Smith predictive structure is proposed to look for performance and robustness improvement. First, internal model control (IMC) and Smith predictor (SP) is used to deal with the time delay, and sliding mode controller (SMCr) is designed to overcome the model mismatch. Simulation results show the effectiveness of the proposed controller compared with conventional ones. 展开更多
关键词 coal fired power plant boiler combustion system main steam pressure sliding mode control Smith predictor internal model control
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Electroacupuncture combined with thunder-fire moxibustion for knee osteoarthritis of cold-damp type:A randomized controlled trial 被引量:5
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作者 Kai-feng DENG Fu-fang SHENG +4 位作者 Xing-cheng WEI Ying JIANG Ying ZHU Zi-long LIAO Ri-lan CHEN 《World Journal of Acupuncture-Moxibustion》 CSCD 2020年第1期33-38,共6页
Objective:To observe the clinical effect differences of knee osteoarthritis(KOA)with cold-damp type between electroacupuncture(EA)combined with thunder-fire moxibustion and medication.Methods:A total of 72 cases of KO... Objective:To observe the clinical effect differences of knee osteoarthritis(KOA)with cold-damp type between electroacupuncture(EA)combined with thunder-fire moxibustion and medication.Methods:A total of 72 cases of KOA patients with cold-damp type were randomly divided into a combined treatment group of EA and thunder-fire moxibustion(combined treatment group)and a medication group,36 cases in each group.In the combined treatment group,the acupoints for EA were Dubi(犊鼻ST35),Neixiyan(内膝眼EX-LE4),Zusanli(足三里ST36),Yanglingquan(阳陵泉GB34),Yinlingquan(阴陵泉SP9),Xuehai(血海SP10),Liangqiu(梁丘ST34)and Heding(鹤顶EX-LE2).During the period of EA,the suspending thunder-fire moxibustion was applied to Shenque CV8)and Guanyuan(关元CV4).In the medication group,diclofenac sodium double release intestine-sol capsule and Fugui gutong capsules were prescribed for oral administration.The treatment for 14 days was taken as one course and the consecutive 2 courses of treatment were required in each group.Before and after treatment,as well as in the follow-up visit,the pain score(visual analogue scale,VAS),the knee function score(Western Ontario and McMaster University,WOMAC,the expressions of interleukin 6(IL-6)and transforming growth factorβ1(TGF-β1)in the joint fluid as well as the difference in the clinical therapeutic effect were observed in the two groups separately.Results:(1)The pain score:compared with those before treatment,the VAS scores were all reduced after treatment and in the follow-up in the two groups(all P<0.05).After treatment and in the follow-up,VAS scores in the combined treatment group were lower than those in the medication group(both P<0.05).(2)The knee function score:WOMAC score of each item,i.e.pain,stiffness and function,as well as the total score after treatment and the follow-up were all lower than those before treatment in the patients of the two groups(all P<0.05).The score of each item,i.e.pain and function,as well as the total score in the combined treatment group were all lower than those in the medication group after treatment and the follow-up respectively(all P<0.05).(3)The expressions of IL-6 and TGF-β1:the level of IL-6 in the joint fluid was reduced after treatment as compared with that before treatment in either group and the level of TGF-β1 was increased,indicating the statistical differences(all P<0.05).After treatment,the level of IL-6 in the combined treatment group was lower than that in the medication group and the level of TGF-β1 was higher than that of the medicating group,indicating the statistical significance(both P<0.05).(4)The total effective rate in the combined treatment group was 97.1%,higher than 78.8%in the medication group,indicating the statistical significance(P<0.05).Conclusion:The clinical effect of the combined treatment of electroacupuncture and the thunder-fire moxibustion is remarkable on knee osteoarthritis of cold-damp type.The combined treatment presents a more advantageous at the sustainability of the therapeutic effect as compared with medication. 展开更多
关键词 Knee OSTEOARTHRITIS Thunder-fire MOXIBUSTION Electroacupuncture(EA) Randomized controlled trial(RCT)
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