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In-flight calibration of the fluxgate magnetometer on Macao Science Satellite-1 被引量:1
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作者 YiXin Qiu Ying Zhang +8 位作者 YaSong Ge AiMin Du ShuQuan Sun Lin Zhao Hao Luo Lei Wang Lin Tian Zhi Li Xiao Feng 《Earth and Planetary Physics》 2025年第3期511-520,共10页
High-precision magnetic field measurements are crucial for understanding Earth’s internal structure,space environment,and dynamic geomagnetic variations.Data from the Fluxgate Magnetometer (FGM) on the Macao Science ... High-precision magnetic field measurements are crucial for understanding Earth’s internal structure,space environment,and dynamic geomagnetic variations.Data from the Fluxgate Magnetometer (FGM) on the Macao Science Satellite-1A (MSS-1A),added to data from other space-based magnetometers,should increase significantly the ability of scientists to observe changes in Earth’s magnetic field over time and space.Additionally,the MSS-1A’s FGM is intended to help identify magnetic disturbances affecting the spacecraft itself.This report focuses on the in-flight calibration of the MSS-1 FGM.A scalar calibration,independent of geomagnetic field models,was performed to correct offsets,sensitivities,and misalignment angles of the FGM.Using seven months of data,we find that the in-flight calibration parameters show good stability.We determined Euler angles describing the rotational relationship between the FGM and the Advanced Stellar Compass (ASC) coordinate system using two approaches:calibration with the CHAOS-7 geomagnetic field model,and simultaneous estimation of Euler angles and Gaussian spherical harmonic coefficients through self-consistent modeling.The accuracy of Euler angles describing the rotation was better than 18 arcsec.The calibrated FGM data exhibit good agreement with the calibrated data of the Vector Field Magnetometer (VFM),which is the primary vector magnetometer of the satellite.These calibration efforts have significantly improved the accuracy of the FGM measurements,which are now providing reliable data for geomagnetic field studies that promise to advance our understanding of the Earth’s magnetic environment. 展开更多
关键词 Macao Science Satellite-1(MSS-1) in-flight calibration Euler angles estimation geomagnetic fields model fluxgate magnetometer
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Simulation-based parameter optimization and development of a split-core fluxgate DC current sensor
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作者 YANG Dechao SHI Junjiang +3 位作者 ZHAO Zhengang HOU Yingjie YANG Kuisong JIANG Xin 《Journal of Measurement Science and Instrumentation》 2025年第4期588-602,共15页
Fluxgate current sensors(FGCSs)are increasingly employed in power systems due to their high-precision characteristics,yet their measurement flexibility remains constrained by conventional closed-core designs.To addres... Fluxgate current sensors(FGCSs)are increasingly employed in power systems due to their high-precision characteristics,yet their measurement flexibility remains constrained by conventional closed-core designs.To address this limitation,we proposed a split-core sensor structure comprising four magnetic core strips,which achieved non-intrusive current measurement while maintaining detection accuracy.An analytical model of the induced electromotive force was established based on the probe’s geometric configuration,followed by finite element simulations to optimize key parameters including core radius,core width,excitation coil turns,and sensing coil configuration.A complete prototype integrating the measurement probe,excitation circuit,and signal processing circuitry was developed and experimentally validated.The experimental results show a sensitivity of 0.1099 V/A,a hysteresis error of 0.559%,and a repeatability error of 1.574%over a measurement range of±10 A.After polynomial fitting-based error compensation,the nonlinearity error was reduced to 0.208%,achieving performance comparable to closed-core sensors.This work provided a practical solution for applications demanding both high measurement accuracy and installation flexibility. 展开更多
关键词 fluxgate current sensor second harmonic method finite element simulation parameter optimization circuit design DC measurement
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In-flight calibration of the spaceborne fluxgate magnetometer in the Martian magnetosheath 被引量:1
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作者 GuoQiang Wang 《Earth and Planetary Physics》 EI CSCD 2022年第6期592-600,共9页
In-flight calibration of the ze ro offset is crucial for ensuring high-precision measure ment of the spaceborne fluxgate magnetomete r.Tianwen-1 is China’s first Mars mission,and its orbiter will re main out of the s... In-flight calibration of the ze ro offset is crucial for ensuring high-precision measure ment of the spaceborne fluxgate magnetomete r.Tianwen-1 is China’s first Mars mission,and its orbiter will re main out of the solar wind for tens of days each year.Previous in-flight calibration methods might not be suitable for this orbiter during such a period.Recently,a new method was proposed by Wang GQ(2022 b),which we refer to as the Wang method Ⅱ for ease of description.Here,we test the performance of this method in the Martian magnetosheath by using magnetic field data measured by the Mars Atmosphere and Volatile EvolutioN(MAVEN) spacecraft.We find that the accuracy of the Wang method Ⅱ is affected by the number of magnetic field subinterval events,the eigenvalues of the minimum variance analysis for each event,and the position of the spacecraft in the magnetosheath.The estimated zero offset varies over a period of~27 days and has a 57.3% probability of accuracy within 2.0 nT.After being smoothed with a temporal window of 27 days,the ze ro offset has a 48.4%(99.3%) probability of accuracy within 1.0(2.0) nT.Our tests suggest that the Wang method Ⅱ provides an option for the Tianwen-1 orbiter to perform in-flight calibration when the orbiter remains out of the solar wind for an extended pe riod of time. 展开更多
关键词 fluxgate magnetometer in-flight calibration zero offset Martian magnetosheath
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Soft sensory-neuromorphic system for closed-loop neuroprostheses
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作者 Jaehyon Kim Sungjun Lee +1 位作者 Jiyong Yoon Donghee Son 《International Journal of Extreme Manufacturing》 2025年第4期2-33,共32页
Prosthetic devices designed to assist individuals with damaged or missing body parts have made significant strides,particularly with advancements in machine intelligence and bioengineering.Initially focused on movemen... Prosthetic devices designed to assist individuals with damaged or missing body parts have made significant strides,particularly with advancements in machine intelligence and bioengineering.Initially focused on movement assistance,the field has shifted towards developing prosthetics that function as seamless extensions of the human body.During this progress,a key challenge remains the reduction of interface artifacts between prosthetic components and biological tissues.Soft electronics offer a promising solution due to their structural flexibility and enhanced tissue adaptability.However,achieving full integration of prosthetics with the human body requires both artificial perception and efficient transmission of physical signals.In this context,synaptic devices have garnered attention as next-generation neuromorphic computing elements because of their low power consumption,ability to enable hardware-based learning,and high compatibility with sensing units.These devices have the potential to create artificial pathways for sensory recognition and motor responses,forming a“sensory-neuromorphic system”that emulates synaptic junctions in biological neurons,thereby connecting with impaired biological tissues.Here,we discuss recent developments in prosthetic components and neuromorphic applications with a focus on sensory perception and sensorimotor actuation.Initially,we explore a prosthetic system with advanced sensory units,mechanical softness,and artificial intelligence,followed by the hardware implementation of memory devices that combine calculation and learning functions.We then highlight the importance and mechanisms of soft-form synaptic devices that are compatible with sensing units.Furthermore,we review an artificial sensory-neuromorphic perception system that replicates various biological senses and facilitates sensorimotor loops from sensory receptors,the spinal cord,and motor neurons.Finally,we propose insights into the future of closed-loop neuroprosthetics through the technical integration of soft electronics,including bio-integrated sensors and synaptic devices,into prosthetic systems. 展开更多
关键词 soft electronics synaptic devices sensory-neuromorphic system closed-loop neuroprosthetics
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Design and Implementation of Closed-Loop Control of Vector Force in Static Push-the-bit Rotary Steering System
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作者 Liang Yao Kang Hong-bo +4 位作者 Liu Yue Chen wen Sun Yan Ma Li Zhao Yan-Wei 《Applied Geophysics》 2025年第3期796-803,896,共9页
Rotary steering systems(RSSs)have been increasingly used to develop horizontal wells.A static push-the-bit RSS uses three hydraulic modules with varying degrees of expansion and contraction to achieve changes in the p... Rotary steering systems(RSSs)have been increasingly used to develop horizontal wells.A static push-the-bit RSS uses three hydraulic modules with varying degrees of expansion and contraction to achieve changes in the pushing force acting on the wellbore in different sizes and directions within a circular range,ultimately allowing the wellbore trajectory to be drilled in a predetermined direction.By analyzing its mathematical principles and the actual characteristics of the instrument,a vector force closed-loop control method,including steering and holding modes,was designed.The adjustment criteria for the three hydraulic modules are determined to achieve rapid adjustment of the vector force.The theoretical feasibility of the developed method was verified by comparing its results with the on-site application data of an imported rotary guidance system. 展开更多
关键词 Static push-the-bit hydraulic modules closed-loop control vector force working mode
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Optimized PID neural network closed-loop control for basal ganglia network in Parkinson's disease
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作者 Hengxi Zhang Honghui Zhang +1 位作者 Shuang Liu Lin Du 《Chinese Physics B》 2025年第12期193-206,共14页
Conventional open-loop deep brain stimulation(DBS)systems with fixed parameters fail to accommodate interindividual pathological differences in Parkinson's disease(PD)management while potentially inducing adverse ... Conventional open-loop deep brain stimulation(DBS)systems with fixed parameters fail to accommodate interindividual pathological differences in Parkinson's disease(PD)management while potentially inducing adverse effects and causing excessive energy consumption.In this paper,we present an adaptive closed-loop framework integrating a Yogi-optimized proportional–integral–derivative neural network(Yogi-PIDNN)controller.The Yogi-augmented gradient adaptation mechanism accelerates the convergence of general PIDNN controllers in high-dimensional nonlinear control systems while reducing control energy usage.In addition,a system identification method establishes input–output dynamics for pre-training stimulation waveforms,bypassing real-time parameter-tuning constraints and thereby enhancing closed-loop adaptability.Finally,a theoretical analysis based on Lyapunov stability criteria establishes a sufficient condition for closed-loop stability within the identified model.Computational validations demonstrate that our approach restores thalamic relay reliability while reducing energy consumption by(81.0±0.7)%across multi-frequency tests.This study advances adaptive neuromodulation by synergizing data-driven pre-training with stability-guaranteed real-time control,offering a novel framework for energy-efficient and personalized Parkinson's therapy. 展开更多
关键词 Parkinson's disease closed-loop deep brain stimulation PID neural network adaptive control
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Fishing Ship Trajectory Tracking Control Based on the Closed-Loop Gain Shaping Algorithm Under Rough Sea
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作者 SONG Chun-yu GUO Te-er SUI Jiang-hua 《China Ocean Engineering》 2025年第2期365-372,共8页
This paper proposes a separated trajectory tracking controller for fishing ships at sea state level 6 to solve the trajectory tracking problem of a fishing ship in a 6-level sea state,and to adapt to different working... This paper proposes a separated trajectory tracking controller for fishing ships at sea state level 6 to solve the trajectory tracking problem of a fishing ship in a 6-level sea state,and to adapt to different working environments and safety requirements.The nonlinear feedback method is used to improve the closed-loop gain shaping algorithm.By introducing the sine function,the problem of excessive control energy of the system can be effectively solved.Moreover,an integral separation design is used to solve the influence of the integral term in conventional PID controllers on the transient performance of the system.In this paper,a common 32.98 m large fiberglass reinforced plastic(FRP)trawler is adopted for simulation research at the winds scale of Beaufort No.7.The results show that the track error is smaller than 3.5 m.The method is safe,feasible,concise and effective and has popularization value in the direction of fishing ship trajectory tracking control.This method can be used to improve the level of informatization and intelligence of fishing ships. 展开更多
关键词 trajectory tracking control nonlinear feedback control fishing ship closed-loop gain shaping algorithm rough sea
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MEMS磁通门传感器有限元仿真方法
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作者 马朝祥 吕阳 +2 位作者 陆玲霞 于淼 朱格民 《传感器与微系统》 北大核心 2026年第2期48-54,共7页
针对MEMS场景下磁通门仿真建模过于简化的问题,提出考虑各向异性磁芯耦合特性的系统性仿真方法。通过采用非线性Jiles-Atherton(J-A)模型和基于张量能量运算的磁滞回线建模方法,得到耦合了磁材料复杂特性的磁芯模型。并探究不同参数对... 针对MEMS场景下磁通门仿真建模过于简化的问题,提出考虑各向异性磁芯耦合特性的系统性仿真方法。通过采用非线性Jiles-Atherton(J-A)模型和基于张量能量运算的磁滞回线建模方法,得到耦合了磁材料复杂特性的磁芯模型。并探究不同参数对传感器性能的影响。结果显示:该仿真方法可有效反映各向异性磁芯材料对磁通门工作特性的影响,验证了激励电流、磁芯厚度和线圈截面积与传感器性能的关系,可为MEMS场景下的磁通门传感器有限元仿真研究及实物制作提供有效参考。 展开更多
关键词 磁通门 有限元仿真 MEMS Jiles-Atherton模型
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高灵敏磁传感器:从经典到量子传感
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作者 柴国志 《物理》 北大核心 2026年第1期19-29,共11页
从古代就用于导航的指南针和罗盘,到地球物理勘探中磁场异常探测,到心、脑磁图中捕捉的生物电活动磁信号,再到物质微观结构与宏观物理现象研究,磁测量的精度直接决定了相关科学发现的深度与技术应用的广度。高灵敏磁传感器是磁测量器件... 从古代就用于导航的指南针和罗盘,到地球物理勘探中磁场异常探测,到心、脑磁图中捕捉的生物电活动磁信号,再到物质微观结构与宏观物理现象研究,磁测量的精度直接决定了相关科学发现的深度与技术应用的广度。高灵敏磁传感器是磁测量器件的核心,其精度已成为磁传感技术发展的核心驱动力与关键评判标准。文章对各种高灵敏度磁传感器进行了梳理总结,以期对磁传感器在不同领域的应用提供参考。 展开更多
关键词 磁传感器 磁通门 磁电阻 磁阻抗 量子磁力仪
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A novel closed-loop vacuum silicon microgyroscope
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作者 夏敦柱 王寿荣 周百令 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期63-67,共5页
A novel closed-loop control strategy of a silicon microgyroscope (SMG) is proposed. The SMG is sealed in metal can package in drive and sense modes and works under the air pressure of 10 Pa. Its quality factor reach... A novel closed-loop control strategy of a silicon microgyroscope (SMG) is proposed. The SMG is sealed in metal can package in drive and sense modes and works under the air pressure of 10 Pa. Its quality factor reaches greater than l0 000. Self-oscillating and closed-loop methods based on electrostatic force feedback are adopted in both measure and control circuits. Both single side driving and sensing methods are used to simplify the drive circuit. These dual channel decomposition and reconstruction closed loops are applied in sense modes. The testing results demonstrate that useful signals and guadrature signals do not interact with each other because of the decoupling of their phases. Under the condition of a scale factor of 9. 6 mV/((°) .s), in a full measurement range of±300 (°)/s, the zero bias stability reaches 28 (°)/h with a nonlinear coefficient of 400 × 10^-6 and a simulated bandwidth of more than 100 Hz. The overall performance is improved by two orders of magnitude in comparison to that at atmospheric pressure. 展开更多
关键词 silicon micro-gyroscope (SMG) self oscillating dual-channel closed-loop detection scale factor zero bias stability
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基于双磁芯检测技术的自激振荡磁通门电流传感器研究
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作者 辛明勇 谭则杰 +2 位作者 徐长宝 王秀境 田兵 《传感器与微系统》 北大核心 2026年第1期72-77,共6页
提出了一种基于双磁芯检测技术和自激振荡技术的新型磁通门电流传感器,该传感器在开环配置下具有较高的测量精度和线性度,并具有高灵敏度和分辨力的特点。该传感器的输出电压是将磁芯C_(1)和C_(2)的激磁电流信号线性叠加后,再滤波解调... 提出了一种基于双磁芯检测技术和自激振荡技术的新型磁通门电流传感器,该传感器在开环配置下具有较高的测量精度和线性度,并具有高灵敏度和分辨力的特点。该传感器的输出电压是将磁芯C_(1)和C_(2)的激磁电流信号线性叠加后,再滤波解调得到的,与传统单磁芯传感器相比,不仅利用第二个磁芯的电流检测能力,提高了灵敏度和分辨力;同时构造互补或者相同的激磁信号,有效抑制传导调制纹波。此研究有助于设计新型闭环自激振荡磁通门电流传感器,实现传导和感应调制纹波同时抑制,从而显著提高测量精度。 展开更多
关键词 双磁芯检测 自激振荡 磁通门电流传感器 调制纹波抑制 高灵敏度
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Wearable Ultrasound Devices for Therapeutic Applications
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作者 Sicheng Chen Qunle Ouyang +5 位作者 Xuanbo Miao Feng Zhang Zehua Chen Xiaoyan Qian Jinwei Xie Zheng Yan 《Nano-Micro Letters》 2026年第2期260-287,共28页
Wearable ultrasound devices represent a transformative advancement in therapeutic applications,offering noninvasive,continuous,and targeted treatment for deep tissues.These systems leverage flexible materials(e.g.,pie... Wearable ultrasound devices represent a transformative advancement in therapeutic applications,offering noninvasive,continuous,and targeted treatment for deep tissues.These systems leverage flexible materials(e.g.,piezoelectric composites,biodegradable polymers)and conformable designs to enable stable integration with dynamic anatomical surfaces.Key innovations include ultrasound-enhanced drug delivery through cavitation-mediated transdermal penetration,accelerated tissue regeneration via mechanical and electrical stimulation,and precise neuromodulation using focused acoustic waves.Recent developments demonstrate wireless operation,real-time monitoring,and closed-loop therapy,facilitated by energy-efficient transducers and AI-driven adaptive control.Despite progress,challenges persist in material durability,clinical validation,and scalable manufacturing.Future directions highlight the integration of nanomaterials,3D-printed architectures,and multimodal sensing for personalized medicine.This technology holds significant potential to redefine chronic disease management,postoperative recovery,and neurorehabilitation,bridging the gap between clinical and home-based care. 展开更多
关键词 Wearable ultrasound devices Drug delivery Tissue regeneration closed-loop therapy NEUROREHABILITATION
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Lexical-Prior-Free Planning:A Symbol-Agnostic Pipeline that Enables LLMs and LRMs to Plan under Obfuscated Interfaces
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作者 Zhendong Du Hanliu Wang Kenji Hashimoto 《Computers, Materials & Continua》 2026年第4期416-451,共36页
Planning in lexical-prior-free environments presents a fundamental challenge for evaluating whether large language models(LLMs)possess genuine structural reasoning capabilities beyond lexical memorization.When predica... Planning in lexical-prior-free environments presents a fundamental challenge for evaluating whether large language models(LLMs)possess genuine structural reasoning capabilities beyond lexical memorization.When predicates and action names are replaced with semantically irrelevant random symbols while preserving logical structures,existing direct generation approaches exhibit severe performance degradation.This paper proposes a symbol-agnostic closed-loop planning pipeline that enables models to construct executable plans through systematic validation and iterative refinement.The system implements a complete generate-verify-repair cycle through six core processing components:semantic comprehension extracts structural constraints,language planner generates text plans,symbol translator performs structure-preserving mapping,consistency checker conducts static screening,Stanford Research Institute Problem Solver(STRIPS)simulator executes step-by-step validation,and VAL(Validator)provides semantic verification.A repair controller orchestrates four targeted strategies addressing typical failure patterns including first-step precondition errors andmid-segment statemaintenance issues.Comprehensive evaluation on PlanBench Mystery Blocksworld demonstrates substantial improvements over baseline approaches across both language models and reasoning models.Ablation studies confirm that each architectural component contributes non-redundantly to overall effectiveness,with targeted repair providing the largest impact,followed by deep constraint extraction and stepwise validation,demonstrating that superior performance emerges from synergistic integration of these mechanisms rather than any single dominant factor.Analysis reveals distinct failure patterns betweenmodel types—languagemodels struggle with local precondition satisfaction while reasoning models face global goal achievement challenges—yet the validation-driven mechanism successfully addresses these diverse weaknesses.A particularly noteworthy finding is the convergence of final success rates across models with varying intrinsic capabilities,suggesting that systematic validation and repair mechanisms play a more decisive role than raw model capacity in lexical-prior-free scenarios.This work establishes a rigorous evaluation framework incorporating statistical significance testing and mechanistic failure analysis,providingmethodological contributions for fair assessment and practical insights into building reliable planning systems under extreme constraint conditions. 展开更多
关键词 LLM planning PDDL symbol obfuscation lexical-prior-free evaluation closed-loop verification validation-driven repair structural reasoning mystery domain
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基于三轴磁通门传感器的衬胶结构缺陷检测分析
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作者 高超 蒲晶菁 +2 位作者 廖雪波 李乾武 杨广宇 《无损检测》 2026年第1期24-29,共6页
衬胶管道因良好的防腐性能与优异的经济性,被广泛应用于核电厂三回路系统。但是衬胶管道在长期服役后易出现破损、脱落和鼓泡等问题,导致金属基体发生腐蚀穿孔,目前尚缺少一种合适的无损检测方法检测其结构缺陷。基于三轴磁通门传感器,... 衬胶管道因良好的防腐性能与优异的经济性,被广泛应用于核电厂三回路系统。但是衬胶管道在长期服役后易出现破损、脱落和鼓泡等问题,导致金属基体发生腐蚀穿孔,目前尚缺少一种合适的无损检测方法检测其结构缺陷。基于三轴磁通门传感器,分析了带缺陷衬胶钢板的表面磁通密度分布,并基于COMSL仿真研究了衬胶缺陷处的磁感应强度分布。试验结果表明,三轴磁通门传感器对衬胶破损具有一定的响应,且在衬胶缺陷处的磁感应强度分布特征明显区别于无缺陷处的。对磁通门传感器测量的数据进行处理,结果表明有效的数据处理可增加缺陷信号的识别度。 展开更多
关键词 磁通门 无损检测 衬胶 缺陷检测
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Defect-engineered gradient reconstruction for the upcycling of spent LiFePO_(4)to generate high-value LiFe_(1−x)Mn_(x)PO_(4)/C cathodes
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作者 Shuaijing Ji Yanqiong Tan +6 位作者 Junwei Wang Fengqian Wang Danpeng Cheng Zhenxing Wang Zhongwen Ouyang Shun Tang Yuancheng Cao 《Journal of Energy Chemistry》 2026年第1期306-316,I0008,共12页
Recycling spent lithium-ion(Li+)batteries is critical for achieving environmental conservation and the strategic recovery of essential resources.Compared with conventional methods for recovering cathode materials,whic... Recycling spent lithium-ion(Li+)batteries is critical for achieving environmental conservation and the strategic recovery of essential resources.Compared with conventional methods for recovering cathode materials,which are energy-intensive and prone to secondary pollution,the direct regeneration approach has emerged as a rapid and highly efficient method,gaining widespread attention in recent years.However,this approach faces major challenges,including degraded electrochemical performances and limited economic value.This study,therefore,proposes a high-value direct regeneration strategy to convert degraded spent LiFePO_(4)(S-LFP)into a gradient manganese(Mn)-doped regenerated LiFe_(0.7)Mn_(0.3)PO_(4)/C(R-LFMP)composite.This method leverages the inherent microcracks and Li vacancies present in S-LFP,likely acting as diffusion channels for the Mn^(2+)/Li^(+)ions.Through a two-step mechanochemical ball-milling and carbothermal reduction process,this approach achieves simultaneous Li replenishment and surface-localised Mn gradient doping with enhanced structural control.Notably,the R-LFMP exhibits an exceptional electrochemical performance.At 0.1 C,it delivers a discharge capacity of 161.4 mA h g^(−1)and an energy density of 563.5 Wh kg^(−1)(representing a 60.5%improvement over S-LFP).Additionally,it maintains 83%capacity retention after 900 cycles at 0.5C,a considerable enhancement compared to commercial LFMP(62%).Furthermore,the regenerated cathode material generates a net profit of$7.102 kg^(−1),surpassing the profitability of conventional recycling methods by 90%.Overall,this study introduces a transformative and sustainable LFP regeneration technology,achieving breakthroughs in electrochemical restoration and high-value recycling,while paving the way for the closed-loop utilisation of LFP-based energy storage systems. 展开更多
关键词 Spent LiFePO_(4)recycling Defect-guided gradient reconstruction Gradient manganese doping closed-loop recycling Economic viability
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Steps towards a^(229)Th ionic nuclear clock in a linear ion trap
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作者 Wen-Ting Gan Zi Li +2 位作者 Chen Wang Xia Hua Xin Tong 《Chinese Physics B》 2026年第2期141-155,共15页
Owing to the presence of a low-energy,long-lived nuclear isomeric state,^(229)Th is an ideal candidate for developing the next generation clock—the nuclear clock—holding great promise for both applied and fundamenta... Owing to the presence of a low-energy,long-lived nuclear isomeric state,^(229)Th is an ideal candidate for developing the next generation clock—the nuclear clock—holding great promise for both applied and fundamental physics.The^(229)Th ionic nuclear optical clock has garnered considerable attention,attributed to its high precision with a relative uncertainty of≤1.5×10^(-19)and the potential for common-mode noise cancellation via self-comparison between the nuclear transition and the electronic transition of thorium ions.In this article,we focus on Th^(n+)ions(n=1,2,3)and present a comprehensive review of the current progress in the development of ionic nuclear clocks,covering essential steps such as ion generation,trapping,and cooling.Furthermore,we discuss the realization of a closed-loop clock cycle,addressing key aspects including stable isomer excitation and efficient isomer deexcitation. 展开更多
关键词 ^(229)Th ionic nuclear clock ion generation ion trapping and cooling closed-loop clock cycle
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Closed-Loop MIMO系统线性预编码技术
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作者 卢鑫 《中国新通信》 2008年第11期67-70,共4页
本文讨论了Closed-Loop MIMO系统在有限反馈资源下如何进行反馈的方法,即两种发射端线性预编码的思路,特别是其中的反馈码本设计问题。由于需要接收端向发射端反馈信道信息,而上行反馈资源又非常有限,所以发射端线性预编码技术成为解决... 本文讨论了Closed-Loop MIMO系统在有限反馈资源下如何进行反馈的方法,即两种发射端线性预编码的思路,特别是其中的反馈码本设计问题。由于需要接收端向发射端反馈信道信息,而上行反馈资源又非常有限,所以发射端线性预编码技术成为解决把MIMO技术应用于新一代蜂窝系统或无线局域网的关键问题之一,具有无限广阔的发展前景。 展开更多
关键词 closed-loop MIMO 系统 预编码 波束赋形 信道状态信息
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Closed-loop cobalt recycling from spent lithium-ion batteries based on a deep eutectic solvent (DES) with easy solvent recovery 被引量:10
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作者 Taibai Li Yige Xiong +4 位作者 Xiaohui Yan Tao Hu Siqi Jing Zhongjie Wang Xiang Ge 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第9期532-538,I0015,共8页
Efficient recycling technology for the rapid growth of spent lithium-ion batteries(LIBs)is essential to tackle the resources and environmental crisis.Hydrometallurgical approach has attracted extensive research due to... Efficient recycling technology for the rapid growth of spent lithium-ion batteries(LIBs)is essential to tackle the resources and environmental crisis.Hydrometallurgical approach has attracted extensive research due to its potential to reduce the consumption of energy and threat to the environment.However,the simultaneous realization of green,efficient and closed-loop recycling is still challenging.Herein,we report a closed-loop and highly efficient approach to recycle lithium cobalt oxide from spent LIBs based on a choline chloride:oxalic acid(ChCl:OA)type deep eutectic solvent(DES).An ultrafast leaching process is observed at 180°C for 10 s with no observable residues.The energy barrier during leaching is calculated to be 113.9 kJ/mol.Noteworthy,the solubility of cobalt ions can be reversibly tuned by simply adding/evaporating deionized water,thus avoiding the addition of precipitant and enabling the easy recovery of the leaching solvent for realizing a closed-loop recycling process.The simultaneous realization of high efficiency,green and closed-loop process is expected to push the DES into practical application for recycling the electrodes of LIBs. 展开更多
关键词 Lithium-ion batteries recycle Deep eutectic solvent closed-loop High efficiency Solvent recovery
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Dynamics and adaptive control of a dual-arm space robot with closed-loop constraints and uncertain inertial parameters 被引量:22
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作者 Ying-Hong Jia Quan Hu Shi-Jie Xu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第1期112-124,共13页
A dynamics-based adaptive control approach is proposed for a planar dual-arm space robot in the presence of closed-loop constraints and uncertain inertial parameters of the payload. The controller is capable of contro... A dynamics-based adaptive control approach is proposed for a planar dual-arm space robot in the presence of closed-loop constraints and uncertain inertial parameters of the payload. The controller is capable of controlling the po- sition and attitude of both the satellite base and the payload grasped by the manipulator end effectors. The equations of motion in reduced-order form for the constrained system are derived by incorporating the constraint equations in terms of accelerations into Kane's equations of the unconstrained system. Model analysis shows that the resulting equations perfectly meet the requirement of adaptive controller design. Consequently, by using an indirect approach, an adaptive control scheme is proposed to accomplish position/attitude trajectory tracking control with the uncertain parameters be- ing estimated on-line. The actuator redundancy due to the closed-loop constraints is utilized to minimize a weighted norm of the joint torques. Global asymptotic stability is proven by using Lyapunov's method, and simulation results are also presented to demonstrate the effectiveness of the proposed approach. 展开更多
关键词 Space robot Dynamics. Adaptive control closed-loop constraint Parameter uncertainty - Kane's equation
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Efficient and accurate worm grinding of spur face gears according to an advanced geometrical analysis and a closed-loop manufacturing process 被引量:8
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作者 ZHOU Yuan-sheng TANG Zhong-wei +2 位作者 SHI Xian-lin TANG Jin-yuan LI Zheng-min-qing 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第1期1-13,共13页
Worm grinding has been applied to manufacture gears to pursue high accuracy and fine surface finish.When the worm used to grind face gears is manufactured with multi-axis computer numerical control(CNC)machining,the m... Worm grinding has been applied to manufacture gears to pursue high accuracy and fine surface finish.When the worm used to grind face gears is manufactured with multi-axis computer numerical control(CNC)machining,the machining accuracy is usually improved by increasing the number of tool paths with more time cost.Differently,this work proposes a generated method to improve the efficiency by dressing the worm surface with only one path,and a closed-loop manufacturing process is applied to ensure the machining accuracy.According to an advanced geometric analysis,the worm surface is practically approximated as a swept surface generated by a planar curve.Meanwhile,this curve is applied as the profile of a dressing wheel,which is used to dress the worm surface.The practical machining is carried out in a CNC machine tool,which was originally used to grind helical gears.Finally,a closed-loop manufacturing process including machining,measurement,and modification is proposed to compensate the machining errors.The proposed method is validated with simulations and practical experiments. 展开更多
关键词 face gears worm grinding worm dressing geometrical analysis closed-loop manufacturing
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