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Petrogenetic and geochemical characteristics of some auriferous granitoids in the Kumasi Basin, Ghana: Implications for geodynamic settings and controls of orogenic gold mineralization in the Edikan Gold Mine
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作者 Emmanuel D.Sunkari Obed Oppong Theophilus K.Agbenyezi 《Deep Underground Science and Engineering》 2025年第3期406-421,共16页
The Edikan Mine,which consists of Fobinso and Esuajah gold deposits,lies within the Asankrangwa Gold Belt of the Birimian Supergroup in the Kumasi Basin.The metasedimentary rocks in the Basins and the faulted metavolc... The Edikan Mine,which consists of Fobinso and Esuajah gold deposits,lies within the Asankrangwa Gold Belt of the Birimian Supergroup in the Kumasi Basin.The metasedimentary rocks in the Basins and the faulted metavolcanic rocks in the Belts that make up the Birimian Supergroup were intruded by granitoids during the Eburnean Orogeny.This research aims to classify granitoids in the Edikan Mine and ascertain the petrogenetic and geochemical characteristics of some auriferous granitoids in the wider Kumasi Basin,Ghana,to understand the implications for geodynamic settings.A multi-methods approach involving field studies,petrographic studies,and whole-rock geochemical analysis was used to achieve the goal of the study.Petrographic studies revealed a relatively high abundance of plagioclase and a low percentage of K-feldspars(anorthoclase and orthoclase)in the Fobinso samples,suggesting that the samples are granodioritic in nature,while the Esuajah samples showed relatively low plagioclase abundance and a high percentage in K-feldspars,indicating that they are granitic.The granitoids from the study areas are co-magmatic.The granitoids in Esuajah and Fobinso are generally enriched in large ion lithophile elements and light rare earth elements than high field strength elements,middle rare earth elements,and heavy rare earth elements,indicating mixing with crustal sources during the evolution of the granitoids.The granitoids were tectonically formed in a syn-collisional+VAG setting,which implies that they were formed in the subduction zone setting.Fobinso granodiorites showed S-type signatures with evidence of extensive crustal contamination,while the Esuajah granites showed I-type signatures with little or no crustal contamination and are peraluminous.Gold mineralization in the study area is structurally and lithologically controlled with shear zones,faulting,and veining as the principal structures controlling the mineralization.The late-stage vein,V3,in the Edikan Mine is characterized by a low vein angle and is mineralized. 展开更多
关键词 Edikan Mine geodynamic setting GRANITOIDS lithologically controlled structurally controlled subduction zone
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A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury
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作者 Qi Liu Jianye Xie +5 位作者 Runxue Zhou Jin Deng Weihong Nie Shuwei Sun Haiping Wang Chunying Shi 《Neural Regeneration Research》 SCIE CAS 2025年第2期503-517,共15页
Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug deliv... Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury. 展开更多
关键词 angiogenesis biomaterial blood-brain barrier cerebral ischemia/reperfusion injury control release drug delivery inflammation QK peptides matrix metalloproteinase-2 NEUROPROTECTION self-assembling nanofiber hydrogel
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Generative Artificial Intelligence in Judicial Applications:Functions,Risks,and Controls
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作者 Hong Wenxiao 《Contemporary Social Sciences》 2025年第1期142-155,共14页
The application of generative artificial intelligence(GAI)in the judicial domain represents an innovative approach to achieving digital justice.GAI’s functionalities are primarily exhibited in the enhancement of judi... The application of generative artificial intelligence(GAI)in the judicial domain represents an innovative approach to achieving digital justice.GAI’s functionalities are primarily exhibited in the enhancement of judicial efficiency,improving the accuracy and fairness of adjudications,promoting the uniform application of the law,and enhancing transparency and engagement in judicial processes.However,these advancements are accompanied by potential risks and challenges in technology,adjudication,and ethics.It is thus essential to strengthen privacy protection during the processing and transmission of data,ensure data security and confidentiality,and establish and refine clear legal norms regarding the roles,responsibilities,and legal obligations of GAI in judicial settings.In addition,ethical guidelines that delineate the behavioral boundaries and value orientations of GAI need to be formulated.Collectively,these elements can form a trinary model of technical controls,legal norms,and ethical constraints,to facilitate the modernization and intelligent development of the judicial system. 展开更多
关键词 GAI application functions RISKS technical controls legal norms ethical constraints
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Analysis of key therapeutic elements in acupuncture therapy and placebo acupuncture controls
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作者 Jian-fei NIU Guan-qun WANG +3 位作者 Xiao-long XIE Shuo DU Bi-hui PENG Ji-ping ZHAO 《World Journal of Acupuncture-Moxibustion》 2025年第2期145-151,共7页
Identifying key acupuncture elements is essential for optimizing sham acupuncture controls.Based on the characteristics and current state of acupuncture therapy,this paper categorizes key acupuncture elements into typ... Identifying key acupuncture elements is essential for optimizing sham acupuncture controls.Based on the characteristics and current state of acupuncture therapy,this paper categorizes key acupuncture elements into types and contents.Taking the former as a clue,it examines the current understanding of key acupuncture elements and underscores the need for further refinement to ensure that sham acupuncture controls more closely approximate physiological inertness.Additionally,it explores strategies and methodologies for advancing the understanding of key acupuncture elements from both the type and content perspectives.Key acupuncture elements should expand the number of included element types.Elements such as acupuncture needles,point selection,point combination,needle insertion,needle manipulation,and needle withdrawal should all be included,and they should be reported in a standardized manner in the trials.Regarding element content,improvements should be made in three key areas to enhance selection accuracy:1.Strengthening the comprehensiveness of relevant theoretical frameworks.2.Emphasizing the role of Traditional Chinese Medicine(TCM)diagnosis and acupoint palpation methods in trial application and reporting.3.Continuously investigating the mechanisms underlying both the specific efficacy and the placebo efficacy of acupuncture. 展开更多
关键词 Key acupuncture elements Placebo acupuncture Sham acupuncture Explanatory randomized controlled trials
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Osteocytic vinculin controls bone mass by modulating Mef2c-driven sclerostin expression in mice
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作者 Yishu Wang Jianmei Huang +7 位作者 Sixiong Lin Lei Qin Dingyu Hao Peijun Zhang Shaochuan Huo Xuenong Zou Di Chen Guozhi Xiao 《Bone Research》 2025年第5期1282-1294,共13页
The focal adhesion(FA)is the structural basis of the cell-extracellular matrix crosstalk and plays important roles in control of organ formation and function.Here we show that expression of FA protein vinculin is dram... The focal adhesion(FA)is the structural basis of the cell-extracellular matrix crosstalk and plays important roles in control of organ formation and function.Here we show that expression of FA protein vinculin is dramatically reduced in osteocytes in patients with aging-related osteoporosis.Vinculin loss severely impaired osteocyte adhesion and dendrite formation.Deleting vinculin using the mouse 10-kb Dmp1-Cre transgenic mice causes dramatic bone loss in the weight-bearing long bones and spine,but not in the skull,in both young and aged mice by impairing osteoblast formation and function without markedly affecting bone resorption.Vinculin loss impairs the anabolic response of skeleton to mechanical loading in mice.Vinculin knockdown increases,while vinculin overexpression decreases,sclerostin expression in osteocytes without impacting expression of Mef2c,a major transcriptional regulator of the Sost gene,which encodes sclerostin.Vinculin interacts with Mef2c and retains the latter in the cytoplasm.Thus,vinculin loss enhances Mef2c nuclear translocation and binding to the Sost enhancer ECR5 to promote sclerostin expression in osteocytes and reduces bone formation.Consistent with this notion,deleting Sost expression in osteocytes reverses the osteopenic phenotypes caused by vinculin loss in mice.Finally,we find that estrogen is a novel regulator of vinculin expression in osteocytes and that vinculin-deficient mice are resistant to ovariectomy-induced bone loss.Thus,we demonstrate a novel mechanism through which vinculin inhibits the Mef2c-driven sclerostin expression in osteocytes to promote bone formation. 展开更多
关键词 focal adhesion fa mef c driven sclerostin expression aging related osteoporosis osteocytic vinculin osteocyte adhesion bone loss control organ formation functionhere focal adhesion
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Coordinated Control Strategy of New Energy Power Generation System with Hybrid Energy Storage Unit 被引量:1
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作者 Yun Zhang Zifen Han +2 位作者 Biao Tian Ning Chen Yi Fan 《Energy Engineering》 EI 2025年第1期167-184,共18页
The new energy power generation is becoming increasingly important in the power system.Such as photovoltaic power generation has become a research hotspot,however,due to the characteristics of light radiation changes,... The new energy power generation is becoming increasingly important in the power system.Such as photovoltaic power generation has become a research hotspot,however,due to the characteristics of light radiation changes,photovoltaic power generation is unstable and random,resulting in a low utilization rate and directly affecting the stability of the power grid.To solve this problem,this paper proposes a coordinated control strategy for a newenergy power generation system with a hybrid energy storage unit based on the lithium iron phosphate-supercapacitor hybrid energy storage unit.Firstly,the variational mode decomposition algorithm is used to separate the high and low frequencies of the power signal,which is conducive to the rapid and accurate suppression of the power fluctuation of the energy storage system.Secondly,the fuzzy control algorithm is introduced to balance the power between energy storage.In this paper,the actual data is used for simulation,and the simulation results show that the strategy realizes the effective suppression of the bus voltage fluctuation and the accurate control of the internal state of the energy storage unit,effectively avoiding problems such as overshoot and over-discharge,and can significantly improve the stability of the photovoltaic power generation systemand the stability of the Direct Current bus.It is of great significance to promote the development of collaborative control technology for photovoltaic hybrid energy storage units. 展开更多
关键词 Photovoltaic power suppression hybrid energy storage unit variationalmodal decomposition fuzzy control power distribution control
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Structural Controls Analysis and Its Correlation with Geothermal Occurrence at Barrier Volcanic Complex (BVC), Turkana, Kenya
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作者 Philip Lomorukai Emekwi Nicholas O. Mariita Patrick Chege Kariuki 《International Journal of Geosciences》 CAS 2024年第3期231-245,共15页
Geothermal is a clean energy source that is freely available in the subsurface. The exploitation of this vital resource needs intensive exploration in order to identify and quantify its occurrence. The three parameter... Geothermal is a clean energy source that is freely available in the subsurface. The exploitation of this vital resource needs intensive exploration in order to identify and quantify its occurrence. The three parameters considered when assessing the viability of a geothermal system include;heat source, fractures and fluids. Geological structures are important in transportation of fluids to and from the heat source aiding in recharge of the geothermal system and enhancing productivity. Remote sensing method was applied in mapping the structures at Barrier Volcanic Complex (BVC) by using hill shading technique which utilized four illumination angles of the sun (azimuth) i.e. 45°, 90°, 150°, and 315°, constant elevation of 45° and exaggeration of 10. The data used was Shuttle Radar Topographic Mission (SRTM) Satellite Imagery. ArcGIS Software was used for lineaments delineation and density mapping, PCI Geomatica was used to generate major faults, while Georose and Rockworks 17 were used to generate the rose diagrams. Geological structural analysis was done by delineating lineaments, determining the density distribution of lineaments and finally determining the structural trends of lineaments. The generated major faults in the area and the location of the occurrence of surface manifestations were compared with the generated lineaments. A total of 260 lineaments were generated whereby at 45° there was a total of 60 lineaments, at 90° 95 lineaments, at 150° 61 lineaments, and at 315° 44 lineaments. The results of structural analysis in the area as shown by the rose diagrams indicate an NNE-SSW and N-S trending of structures. In conclusion, the study area is highly fractured as indicated by the presence of numerous lineaments. These lineaments provide good recharge to the geothermal system and enhance the geothermal reservoir in the area. 展开更多
关键词 Geothermal Resource LINEAMENTS Lineaments Density Structural controls
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Effects of dust controls on respirable coal mine dust composition and particle sizes:case studies on auxiliary scrubbers and canopy air curtain
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作者 F.Animah C.Keles +1 位作者 W.R.Reed E.Sarver 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期86-101,共16页
Control of dust in underground coal mines is critical for mitigating both safety and health hazards.For decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the effective... Control of dust in underground coal mines is critical for mitigating both safety and health hazards.For decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the effectiveness of various dust control technologies in coal mines.Recent studies have included the evaluation of auxiliary scrubbers to reduce respirable dust downstream of active mining and the use of canopy air curtains(CACs)to reduce respirable dust in key operator positions.While detailed dust characterization was not a focus of such studies,this is a growing area of interest.Using preserved filter samples from three previous NIOSH studies,the current work aims to explore the effect of two different scrubbers(one wet and one dry)and a roof bolter CAC on respirable dust composition and particle size distribution.For this,the preserved filter samples were analyzed by thermogravimetric analysis and/or scanning electron microscopy with energy dispersive X-ray.Results indicate that dust composition was not appreciably affected by either scrubber or the CAC.However,the wet scrubber and CAC appeared to decrease the overall particle size distribution.Such an effect of the dry scrubber was not consistently observed,but this is probably related to the particular sampling location downstream of the scrubber which allowed for significant mixing of the scrubber exhaust and other return air.Aside from the insights gained with respect to the three specific dust control case studies revisited here,this work demonstrates the value of preserved dust samples for follow-up investigation more broadly. 展开更多
关键词 Respirable dust Dust control SEM–EDX SCRUBBER Canopy air curtain SILICA
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Model-free Predictive Control of Motor Drives:A Review 被引量:2
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作者 Chenhui Zhou Yongchang Zhang Haitao Yang 《CES Transactions on Electrical Machines and Systems》 2025年第1期76-90,共15页
Model predictive control(MPC)has been deemed as an attractive control method in motor drives by virtue of its simple structure,convenient multi-objective optimization,and satisfactory dynamic performance.However,the s... Model predictive control(MPC)has been deemed as an attractive control method in motor drives by virtue of its simple structure,convenient multi-objective optimization,and satisfactory dynamic performance.However,the strong reliance on mathematical models seriously restrains its practical application.Therefore,improving the robustness of MPC has attained significant attentions in the last two decades,followed by which,model-free predictive control(MFPC)comes into existence.This article aims to reveal the current state of MFPC strategies for motor drives and give the categorization from the perspective of implementation.Based on this review,the principles of the reported MFPC strategies are introduced in detail,as well as the challenges encountered in technology realization.In addition,some of typical and important concepts are experimentally validated via case studies to evaluate the performance and highlight their features.Finally,the future trends of MFPC are discussed based on the current state and reported developments. 展开更多
关键词 Model predictive control Motor drives Parameter robustness Model-free predictive control
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Cooperative maximum adhesion tracking control for multi-motor electric locomotives 被引量:1
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作者 Leiting Zhao Yongxiang Wang +3 位作者 Kan Liu Liran Li Jingyuan Zhan Qingliang Liu 《Railway Sciences》 2025年第1期22-36,共15页
Purpose–This study aims to propose a cooperative adhesion control method for trains with multiple motors electric locomotives.The method is intended to optimize the output torque of each motor,maximize the utilizatio... Purpose–This study aims to propose a cooperative adhesion control method for trains with multiple motors electric locomotives.The method is intended to optimize the output torque of each motor,maximize the utilization of train adhesion within the total torque command,reduce the train skidding/sliding phenomenon and achieve optimal adhesion utilization for each axle,thus realizing the optimal allocation of the multi-motor electric locomotives.Design/methodology/approach–In this study,a model predictive control(MPC)-based cooperative maximum adhesion tracking control method for multi-motor electric locomotives is presented.Firstly,train traction system with multiple motors is constructed in accordance with Newton’s second law.These equations include the train dynamics equations,the axle dynamics equations,and the wheel-rail adhesion coefficient equations.Then,a new MPC-based multi-axle adhesion co-optimization method is put forward.This method calculates the optimal output torque through real-time iteration based on the known reference slip speed to achieve multi-axle co-optimization under different circumstances.Findings–This paper presents a MPC system designed for the cooperative control of multi-axle adhesion.The results indicate that the proposed control system is able to optimize the adhesion of multiple axles under numerous different conditions and achieve the optimal power distribution based on the reduction of train skidding/sliding.Originality/value–This study presents a novel cooperative adhesion tracking control scheme.It is designed for multi-motor electric locomotives,which has rarely been studied before.And simulations are carried out in different conditions,including variable surfaces and motor failing. 展开更多
关键词 Cooperative control Adhesion control Model predictive control Slip prevent
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BB Controlwave控制器运行状态监测系统设计
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作者 张向京 贺杰 +3 位作者 海显莲 张金玲 李丹 刘慧 《软件》 2025年第7期146-148,共3页
本文面向BB Controlwave控制器运行监测,设计了基于B/S架构的系统,采集CPU繁忙时间、闪存占用、RAM使用率等参数,采用星型工业以太网并行监测54台设备,设定多级预警并推送告警信息。系统三个月内预警准确率达95.3%,成功识别15次故障隐患... 本文面向BB Controlwave控制器运行监测,设计了基于B/S架构的系统,采集CPU繁忙时间、闪存占用、RAM使用率等参数,采用星型工业以太网并行监测54台设备,设定多级预警并推送告警信息。系统三个月内预警准确率达95.3%,成功识别15次故障隐患,避免8次停机,有效支撑了预防性维护。 展开更多
关键词 控制器状态监测 预警机制 数据采集
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An asymmetrically variable wingtip anhedral angles morphing aircraft based on incremental sliding mode control:Improving lateral maneuver capability 被引量:1
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作者 Xiaodong LIU Yong XU Jianqiao LUO 《Chinese Journal of Aeronautics》 2025年第1期455-470,共16页
This paper presents the design of an asymmetrically variable wingtip anhedral angles morphing aircraft,inspired by biomimetic mechanisms,to enhance lateral maneuver capability.Firstly,we establish a lateral dynamic mo... This paper presents the design of an asymmetrically variable wingtip anhedral angles morphing aircraft,inspired by biomimetic mechanisms,to enhance lateral maneuver capability.Firstly,we establish a lateral dynamic model considering additional forces and moments resulting during the morphing process,and convert it into a Multiple Input Multiple Output(MIMO)virtual control system by importing virtual inputs.Secondly,a classical dynamics inversion controller is designed for the outer-loop system.A new Global Fast Terminal Incremental Sliding Mode Controller(NDO-GFTISMC)is proposed for the inner-loop system,in which an adaptive law is implemented to weaken control surface chattering,and a Nonlinear Disturbance Observer(NDO)is integrated to compensate for unknown disturbances.The whole control system is proven semiglobally uniformly ultimately bounded based on the multi-Lyapunov function method.Furthermore,we consider tracking errors and self-characteristics of actuators,a quadratic programmingbased dynamic control allocation law is designed,which allocates virtual control inputs to the asymmetrically deformed wingtip and rudder.Actuator dynamic models are incorporated to ensure physical realizability of designed allocation law.Finally,comparative experimental results validate the effectiveness of the designed control system and control allocation law.The NDO-GFTISMC features faster convergence,stronger robustness,and 81.25%and 75.0%reduction in maximum state tracking error under uncertainty compared to the Incremental Nonlinear Dynamic Inversion Controller based on NDO(NDO-INDI)and Incremental Sliding Mode Controller based on NDO(NDO-ISMC),respectively.The design of the morphing aircraft significantly enhances lateral maneuver capability,maintaining a substantial control margin during lateral maneuvering,reducing the burden of the rudder surface,and effectively solving the actuator saturation problem of traditional aircraft during lateral maneuvering. 展开更多
关键词 Morphing aircraft Lateral maneuver capability Incremental sliding mode control Multi-Lyapunov function method control theory control allocation law
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Passive activity enhances residual control ability in patients with complete spinal cord injury 被引量:2
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作者 Yanqing Xiao Mingming Gao +6 位作者 Zejia He Jia Zheng Hongming Bai Jia-Sheng Rao Guiyun Song Wei Song Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS 2025年第8期2337-2347,共11页
Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these... Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface electromyography.In this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord injury.Eleven patients with chronic complete thoracic spinal cord injury were recruited.Surface electromyography data from eight major leg muscles were acquired and compared before and after the passive activity protocol.The results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of activation.Although the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically significant.These findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury. 展开更多
关键词 complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task
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Fault-observer-based iterative learning model predictive controller for trajectory tracking of hypersonic vehicles 被引量:1
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作者 CUI Peng GAO Changsheng AN Ruoming 《Journal of Systems Engineering and Electronics》 2025年第3期803-813,共11页
This work proposes the application of an iterative learning model predictive control(ILMPC)approach based on an adaptive fault observer(FOBILMPC)for fault-tolerant control and trajectory tracking in air-breathing hype... This work proposes the application of an iterative learning model predictive control(ILMPC)approach based on an adaptive fault observer(FOBILMPC)for fault-tolerant control and trajectory tracking in air-breathing hypersonic vehicles.In order to increase the control amount,this online control legislation makes use of model predictive control(MPC)that is based on the concept of iterative learning control(ILC).By using offline data to decrease the linearized model’s faults,the strategy may effectively increase the robustness of the control system and guarantee that disturbances can be suppressed.An adaptive fault observer is created based on the suggested ILMPC approach in order to enhance overall fault tolerance by estimating and compensating for actuator disturbance and fault degree.During the derivation process,a linearized model of longitudinal dynamics is established.The suggested ILMPC approach is likely to be used in the design of hypersonic vehicle control systems since numerical simulations have demonstrated that it can decrease tracking error and speed up convergence when compared to the offline controller. 展开更多
关键词 hypersonic vehicle actuator fault tracking control iterative learning control(ILC) model predictive control(MPC) fault observer
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A Comprehensive Review of Torque and Speed Control Strategies for Switched Reluctance Motor Drives 被引量:1
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作者 Sreeram K Preetha P K +1 位作者 Javier Rodríguez-García Carlosálvarez-Bel 《CES Transactions on Electrical Machines and Systems》 2025年第1期46-75,共30页
Switched Reluctance Motors(SRMs),outfitted with rugged construction,good speed range,high torque density,and rare earth-free nature that outweigh induction motors(IM)and permanent magnet synchronous motor(PMSM),afford... Switched Reluctance Motors(SRMs),outfitted with rugged construction,good speed range,high torque density,and rare earth-free nature that outweigh induction motors(IM)and permanent magnet synchronous motor(PMSM),afford a broad range of applications in the domain of electric vehicles(EVs).Standard copper magnetic wire and low-carbon steel laminations are used to construct SRMs,which give them high efficiency in the range of 85-95%.Despite SRM's desirable features over traditional motor-speed drives,high torque ripples and radial distortions constrain their deployment in EVs.Precise rotor position is imperative for effective management of the speed and torque of SRMs.This paper provides an illustrative compendium on review of the torque-speed control and ripple mitigation techniques using design enhancements and control methods for SRM drives for EV applications.The various schemes were evaluated on their performance metricsoperational speed range,control complexity,practical realization,need for pre-stored parameters(look-up tables of current,inductance and torque profiles)and motor controller memory requirements.The findings provide valuable insights into balancing the gains and trade-offs associated with EV applications.Furthermore,they pinpoint opportunities for enhancement by analyzing the cost and technical aspects of different SRM controllers. 展开更多
关键词 Electric vehicles Switched reluctance motor Speed control Torque control Traction motor Torque ripple
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Modeling and control of automatic voltage regulation for a hydropower plant using advanced model predictive control 被引量:1
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作者 Ebunle Akupan Rene Willy Stephen Tounsi Fokui 《Global Energy Interconnection》 2025年第2期269-285,共17页
Fluctuating voltage levels in power grids necessitate automatic voltage regulators(AVRs)to ensure stability.This study examined the modeling and control of AVR in hydroelectric power plants using model predictive cont... Fluctuating voltage levels in power grids necessitate automatic voltage regulators(AVRs)to ensure stability.This study examined the modeling and control of AVR in hydroelectric power plants using model predictive control(MPC),which utilizes an extensive mathe-matical model of the voltage regulation system to optimize the control actions over a defined prediction horizon.This predictive feature enables MPC to minimize voltage deviations while accounting for operational constraints,thereby improving stability and performance under dynamic conditions.Thefindings were compared with those derived from an optimal proportional integral derivative(PID)con-troller designed using the artificial bee colony(ABC)algorithm.Although the ABC-PID method adjusts the PID parameters based on historical data,it may be difficult to adapt to real-time changes in system dynamics under constraints.Comprehensive simulations assessed both frameworks,emphasizing performance metrics such as disturbance rejection,response to load changes,and resilience to uncertainties.The results show that both MPC and ABC-PID methods effectively achieved accurate voltage regulation;however,MPC excelled in controlling overshoot and settling time—recording 0.0%and 0.25 s,respectively.This demonstrates greater robustness compared to conventional control methods that optimize PID parameters based on performance criteria derived from actual system behavior,which exhibited settling times and overshoots exceeding 0.41 s and 5.0%,respectively.The controllers were implemented using MATLAB/Simulink software,indicating a significant advancement for power plant engineers pursuing state-of-the-art automatic voltage regulations. 展开更多
关键词 Automatic voltage regulation Artificial bee colony Evolutionary techniques Model predictive control PID controller HYDROPOWER
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Constrained Networked Predictive Control for Nonlinear Systems Using a High-Order Fully Actuated System Approach 被引量:1
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作者 Yi Huang Guo-Ping Liu +1 位作者 Yi Yu Wenshan Hu 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期478-480,共3页
Dear Editor,In this letter,a constrained networked predictive control strategy is proposed for the optimal control problem of complex nonlinear highorder fully actuated(HOFA)systems with noises.The method can effectiv... Dear Editor,In this letter,a constrained networked predictive control strategy is proposed for the optimal control problem of complex nonlinear highorder fully actuated(HOFA)systems with noises.The method can effectively deal with nonlinearities,constraints,and noises in the system,optimize the performance metric,and present an upper bound on the stable output of the system. 展开更多
关键词 optimal control problem constrained networked predictive control strategy Performance Optimization present upper bound Nonlinear Systems NOISES Constrained Networked Predictive control High Order Fully Actuated Systems
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Psychological effects of virtual reality intervention on breast cancer patients with different personalities: A randomized controlled trial 被引量:4
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作者 Shanshan Wu Guodu Liu +9 位作者 Jie Yang Xinxin Xie Mei-E Wu Lili Wang Yanhui Zhang Jinmei Chen Xiaowei Wang Wanjiao Li Yihong Qiu Jie Chen 《International Journal of Nursing Sciences》 2025年第2期107-114,共8页
Objectives:To explore the efficacy and safety of virtual reality(VR)in relieving negative emotions in patients with breast cancer with different personalities.Methods:A randomized controlled trial was conducted.Betwee... Objectives:To explore the efficacy and safety of virtual reality(VR)in relieving negative emotions in patients with breast cancer with different personalities.Methods:A randomized controlled trial was conducted.Between April 2023 and October 2023,we enrolled patients with breast cancer treated in the Department of Breast Cancer and Oncology at Sun Yat-Sen Memorial Hospital,Sun Yat-Sen University,Guangdong Province.The patients were randomly divided into an intervention group(n=118)and a control group(n=119)using block randomization.The intervention group received the VR intervention 3-5 times over 5±2 weeks using natural landscapes with music or relaxation guidance,and the duration of each VR intervention was 15±3 min.The control group received routine nursing care,including disease education and psychological counseling.Patients were assessed using the Type D Scale,Positive and Negative Affect Scale,and Distress Thermometer,and adverse events during the intervention were recorded.Results:Overall,85 patients completed the study(44 in the intervention group and 41 in the control group).Patients with Type D personalities showed more negative emotions[25.0(21.5,27.5)vs.19.0(16.0,24.0),P=0.001]and distressed attitudes[4.0(2.0,5.0)vs.3.0(1.0,4.0),P=0.020]with fewer positive emotions(27.2±5.6 vs.31.0±5.9,P=0.014)than those with non-Type D personalities.Total population analysis revealed no significant differences between the groups.However,in the subgroup analysis,patients with Type D personalities in the intervention group showed greater relief from negative emotions than those in the control group[median difference,-5.0(-9.0,-2.5)vs.-2.0(-4.0,2.0),P=0.046].No significant differences were found between groups of patients with non-Type D personality traits.The proportion of adverse events was not significantly different between groups(P=0.110).Conclusions:Breast cancer patients with Type D personalities suffer more severe negative emotions and distress,and more attention should be paid to them.VR intervention significantly and safely reduced negative emotions in patients with Type D personalities. 展开更多
关键词 Breast neoplasms Rehabilitation research Randomized controlled trial Type D personality Virtual reality
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A review of superplastic magnesium alloys:Focusing on alloying strategy,grain structure control and deformation mechanisms 被引量:2
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作者 Siqing Wang Min Zha +5 位作者 Hailong Jia Yajie Yang Dawei Wang Cheng Wang Yipeng Gao Hui-Yuan Wang 《Journal of Materials Science & Technology》 2025年第8期303-319,共17页
In response to the urgent demand for lightweight,magnesium(Mg)alloys have garnered considerable attention owing to their low density.Nonetheless,the intrinsic poor room-temperature formability of Mg alloys remains a m... In response to the urgent demand for lightweight,magnesium(Mg)alloys have garnered considerable attention owing to their low density.Nonetheless,the intrinsic poor room-temperature formability of Mg alloys remains a major obstacle in shaping precise complex components,necessitating the development of superplastic Mg alloys.Excellent superplasticity is usually acquired in high-alloyed Mg alloys with enhanced microstructural thermal stability facilitated by abundant optimized second-phase particles.While for cost-effective low-alloyed Mg alloys lacking particles,regulating solute segregation has emerged as a promising approach to achieve superplasticity recently.Moreover,the potential of bimodal-grained Mg alloys for superplastic deformation has been revealed,expanding the options for designing superplastic materials beyond the conventional approach of fine-grained microstructures.This study reviews significant developments in superplastic Mg alloys from the view of alloying strategies,grain structure control and deformation mechanisms,with potential implications for future research and industrial applications of superplastic Mg alloys. 展开更多
关键词 Mg alloys SUPERPLASTICITY Second-phase particles Solute segregation Microstructure control
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Robust Backstepping Control of a Quadrotor Unmanned Aerial Vehicle under Colored Noises
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作者 Mehmet Karahan 《Computers, Materials & Continua》 SCIE EI 2025年第1期777-798,共22页
Advances in software and hardware technologies have facilitated the production of quadrotor unmanned aerial vehicles(UAVs).Nowadays,people actively use quadrotor UAVs in essential missions such as search and rescue,co... Advances in software and hardware technologies have facilitated the production of quadrotor unmanned aerial vehicles(UAVs).Nowadays,people actively use quadrotor UAVs in essential missions such as search and rescue,counter-terrorism,firefighting,surveillance,and cargo transportation.While performing these tasks,quadrotors must operate in noisy environments.Therefore,a robust controller design that can control the altitude and attitude of the quadrotor in noisy environments is of great importance.Many researchers have focused only on white Gaussian noise in their studies,whereas researchers need to consider the effects of all colored noises during the operation of the quadrotor.This study aims to design a robust controller that is resistant to all colored noises.Firstly,a nonlinear quadrotormodel was created with MATLAB.Then,a backstepping controller resistant to colored noises was designed.Thedesigned backstepping controller was tested under Gaussian white,pink,brown,blue,and purple noises.PID and Lyapunov-based controller designswere also carried out,and their time responses(rise time,overshoot,settling time)were compared with those of the backstepping controller.In the simulations,time was in seconds,altitude was in meters,and roll,pitch,and yaw references were in radians.Rise and settling time values were in seconds,and overshoot value was in percent.When the obtained values are examined,simulations prove that the proposed backstepping controller has the least overshoot and the shortest settling time under all noise types. 展开更多
关键词 Backstepping control colored noises Gaussian noise Lyapunov stability QUADROTOR ROBUSTNESS PID control
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