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Advanced Techniques for Precision Assessment in UAV LiDAR Systems
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作者 Hany Abdel-MAKSOUD Tarek Abdel AZIZ +1 位作者 Ahmed S.ELSHARKAWY OsamaMOURSY 《Journal of Geodesy and Geoinformation Science》 2025年第2期90-107,共18页
The increasing use of UAV-based LiDAR systems for high-resolution mapping highlights the need for reliable,field-validated accuracy assessment methods.This study presents a practical technique for evaluating geometric... The increasing use of UAV-based LiDAR systems for high-resolution mapping highlights the need for reliable,field-validated accuracy assessment methods.This study presents a practical technique for evaluating geometric and radiometric performance using georeferenced,high-reflectivity foil targets.The method enables precise extraction of target centers and correction of systematic georeferencing errors through 3D transformation.The approach was applied at the Tora Cement Factory in Cairo,Egypt—an industrial site with complex topography—using a DJI Matrice 300 RTK UAV equipped with the Zenmuse L1 LiDAR sensor and Zenmuse P1 photogrammetric camera.Three test flights were performed at altitudes of 50 m(nadir and oblique)and 70 m(oblique),with a high-resolution Structure-from-Motion(SfM)point cloud generated for reference.After transformation,the global RMSE of the LiDAR dataset was reduced to approximately 2.8∼3.2 cm,improving upon the raw uncorrected accuracy of up to 4.6 cm.Surface-wise comparisons showed RMSEs of 3.1 cm on flat areas,3.8 cm on rugged terrain,and 4.5 cm on vertical structures.Additionally,the RGB data embedded in the LiDAR point cloud exhibited a systematic spatial offset between 18 and 43 cm,with an average internal standard deviation near 5 cm,indicating a potential limitation for radiometric applications.The proposed method offers a cost-effective,accurate,and repeatable solution for UAV LiDAR validation and supports operational deployment,quality assurance,and system calibration in real-world scenarios. 展开更多
关键词 UAV LIDAR precision ACCURACY
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Precision Synchronous Control of Multiple Motion Systems:A Tube-Based MPC Approach
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作者 Shuaiqi Chen Fazhi Song +3 位作者 Yue Dong Ning Cui Yang Liu Xinkai Chen 《IEEE/CAA Journal of Automatica Sinica》 2025年第5期974-988,共15页
Lithography machines operate in scanning mode for the fabrication of large-scale integrated circuits(ICs),requiring high-precision synchronous motion between the reticle and wafer stages.Disturbances generated by each... Lithography machines operate in scanning mode for the fabrication of large-scale integrated circuits(ICs),requiring high-precision synchronous motion between the reticle and wafer stages.Disturbances generated by each stage during high-acceleration movements are transmitted through the base frame,resulting in degradation of synchronization performance.To address this challenge,this paper proposes a tube-based model predictive control(tube-MPC)approach for synchronization in lithography machines.First,the proposed modeling method accurately characterizes the coupling disturbances and synchronization dynamics.Subsequently,a tube-MPC approach is developed to ensure that the states of the nominal system are constrained within the terminal constraint set.To reduce the complexity of online computations,an approach is employed to transform online optimization problems into offline problems by creating an online lookup table.This enables the determination of optimal control inputs via a simplified online optimization algorithm.The robustness and trajectory tracking performance of the proposed approach are verified through simulation experiments,demonstrating its effectiveness in enhancing the synchronization performance of multiple motion systems. 展开更多
关键词 Coupled disturbance model predictive control multiple systems precision motion control(PMC) robust control wafer scanner
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Reshaping“Cerebellar Inhibition”:Mechanistic Insights and Precision Medicine Perspectives for rTMS in Machado-Joseph Disease
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作者 HAN Ya-Zhen ZHOU Jie +2 位作者 CHEN Yu-Chao GAO Zhong-Ming CHE Xian-Wei 《生物化学与生物物理进展》 北大核心 2026年第2期505-510,共6页
Machado-Joseph disease,or spinocerebellar ataxia type 3(SCA3),represents the most common autosomal dominant cerebellar ataxia worldwide.Despite its progressive and debilitating nature,disease-modifying therapies remai... Machado-Joseph disease,or spinocerebellar ataxia type 3(SCA3),represents the most common autosomal dominant cerebellar ataxia worldwide.Despite its progressive and debilitating nature,disease-modifying therapies remain elusive.Repetitive transcranial magnetic stimulation(rTMS)has emerged as a promising non-invasive intervention;however,its clinical application has been hindered by inconsistent protocols and a lack of mechanistic understanding.A recent landmark study published in Brain Stimulation by Chen et al.addressed these challenges by combining a high-dose intermittent theta-burst stimulation(iTBS)protocol with concurrent transcranial magnetic stimulation-electroencephalography(TMS-EEG).This commentary provides an in-depth analysis of their findings,highlighting the restoration of cerebello-cortical inhibition(CBI)as a key therapeutic mechanism.Furthermore,we discuss the broader implications of this work,proposing that future translational research should integrate accelerated iTBS(aiTBS)paradigms,cortical response measurements(CRM),and individualized neuro-navigation to establish a new era of precision neuromodulation for ataxia. 展开更多
关键词 Machado-Joseph disease(spinocerebellar ataxia type 3 SCA3) transcranial magnetic stimulationelectroencephalography(TMS-EEG) cerebello-cortical inhibition NEUROMODULATION precision medicine
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Synthetic biology and metabolomics-driven precision crop design
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作者 Shuangxia Jin Qinlong Zhu +1 位作者 Qiao Zhao Shouchuang Wang 《The Crop Journal》 2026年第1期4-7,共4页
1.Introduction Crop breeding is transitioning to engineering by synthetic biology.Conventional breeding,constrained by limited genetic variation and lengthy development cycles,cannot meet the challenges of micronutrie... 1.Introduction Crop breeding is transitioning to engineering by synthetic biology.Conventional breeding,constrained by limited genetic variation and lengthy development cycles,cannot meet the challenges of micronutrient malnutrition and yield reductions from climate change with sufficient speed or precision[1].Consequently,agriculture is transitioning from selection-based breeding to designbased engineering.Synthetic biology enables the precision modification of metabolic pathways and the construction of novel trait combinations[1,2].This special issue,Synthetic Biology for Crop Improvement,brings together 26 articles that showcase the field’s transition from laboratory curiosity to field-validated agricultural technology.The collection spans 13 plant species,from staple grains and major industrial crops to horticultural and medicinal plants,demonstrating the universal applicability of metabolic engineering.These studies reveal maturation toward field readiness:independent groups achieving reproducible results in identical pathways,greenhouse concepts advancing to multi-season field trials,and engineered traits delivering measurable agronomic value.This progression answers the central question in crop synthetic biology,shifting the paradigm from asking“can it work?”to demonstrating“how it works,and here are the yields”.This transformation is grounded in understanding and manipulating plant metabolism at molecular resolution[3]. 展开更多
关键词 syntheticbiology micronutrient malnutrition metabolomics precisioncropdesign precision modification metabolic pathways yield reductions synthetic biologyconventional construction nove
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Machine Intelligence for Mental Health Diagnosis: A Systematic Review of Methods, Algorithms, and Key Challenges
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作者 Ravita Chahar Ashutosh Kumar Dubey 《Computers, Materials & Continua》 2026年第1期67-131,共65页
Objective:The increasing global prevalence of mental health disorders highlights the urgent need for the development of innovative diagnostic methods.Conditions such as anxiety,depression,stress,bipolar disorder(BD),a... Objective:The increasing global prevalence of mental health disorders highlights the urgent need for the development of innovative diagnostic methods.Conditions such as anxiety,depression,stress,bipolar disorder(BD),and autism spectrum disorder(ASD)frequently arise from the complex interplay of demographic,biological,and socioeconomic factors,resulting in aggravated symptoms.This review investigates machine intelligence approaches for the early detection and prediction of mental health conditions.Methods:The preferred reporting items for systematic reviews and meta-analyses(PRISMA)framework was employed to conduct a systematic review and analysis covering the period 2018 to 2025.The potential impact of machine intelligence methods was assessed by considering various strategies,hybridization of algorithms,tools,techniques,and datasets,and their applicability.Results:Through a systematic review of studies concentrating on the prediction and evaluation of mental disorders using machine intelligence algorithms,advancements,limitations,and gaps in current methodologies were highlighted.The datasets and tools utilized in these investigations were examined,offering a detailed overview of the status of computational models in understanding and diagnosing mental health disorders.Recent research indicated considerable improvements in diagnostic accuracy and treatment effectiveness,particularly for depression and anxiety,which have shown the greatest methodological diversity and notable advancements in machine intelligence.Conclusions:Despite these improvements,challenges persist,including the need for more diverse datasets,ethical issues surrounding data privacy and algorithmic bias,and obstacles to integrating these technologies into clinical settings.This synthesis emphasizes the transformative potential of machine intelligence in enhancing mental healthcare. 展开更多
关键词 Mental health machine intelligence artificial intelligence deep learning mental disorders diagnostic precision
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Artificial intelligence and machine learning-driven advancements in gastrointestinal cancer:Paving the way for precision medicine
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作者 Chahat Suri Yashwant K Ratre +2 位作者 Babita Pande LVKS Bhaskar Henu K Verma 《World Journal of Gastroenterology》 2026年第1期14-36,共23页
Gastrointestinal(GI)cancers remain a leading cause of cancer-related morbidity and mortality worldwide.Artificial intelligence(AI),particularly machine learning and deep learning(DL),has shown promise in enhancing can... Gastrointestinal(GI)cancers remain a leading cause of cancer-related morbidity and mortality worldwide.Artificial intelligence(AI),particularly machine learning and deep learning(DL),has shown promise in enhancing cancer detection,diagnosis,and prognostication.A narrative review of literature published from January 2015 to march 2025 was conducted using PubMed,Web of Science,and Scopus.Search terms included"gastrointestinal cancer","artificial intelligence","machine learning","deep learning","radiomics","multimodal detection"and"predictive modeling".Studies were included if they focused on clinically relevant AI applications in GI oncology.AI algorithms for GI cancer detection have achieved high performance across imaging modalities,with endoscopic DL systems reporting accuracies of 85%-97%for polyp detection and segmentation.Radiomics-based models have predicted molecular biomarkers such as programmed cell death ligand 2 expression with area under the curves up to 0.92.Large language models applied to radiology reports demonstrated diagnostic accuracy comparable to junior radiologists(78.9%vs 80.0%),though without incremental value when combined with human interpretation.Multimodal AI approaches integrating imaging,pathology,and clinical data show emerging potential for precision oncology.AI in GI oncology has reached clinically relevant accuracy levels in multiple diagnostic tasks,with multimodal approaches and predictive biomarker modeling offering new opportunities for personalized care.However,broader validation,integration into clinical workflows,and attention to ethical,legal,and social implications remain critical for widespread adoption. 展开更多
关键词 Artificial intelligence Gastrointestinal cancer precision medicine Multimodal detection Machine learning
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MEMS gyroscope technology in defence systems:An application-oriented perspective with new analytical results
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作者 Behzad Ahi 《Defence Technology(防务技术)》 2026年第1期389-406,共18页
Microelectromechanical systems(MEMS)technology has gained significant attention over the past decade for measuring inertial angular velocity.However,due to inherent complexity,MEMS gyroscopes typically feature up to t... Microelectromechanical systems(MEMS)technology has gained significant attention over the past decade for measuring inertial angular velocity.However,due to inherent complexity,MEMS gyroscopes typically feature up to ten times more parameters than traditional sensors,making selection a challenging task even for experts.This study addresses this challenge,focusing on defensive guidance,navigation,and control(GNC)systems where precise and reliable angular velocity measurement is critical to overall performance.A comprehensive mathematical model is introduced to encapsulate all key MEMS parameters,accompanied by discussions on calibration and Allan variance interpretation.For six leading MEMS gyroscope applications,namely inertial navigation,integrated navigation,autopilot systems,rotating projectiles,homing guidance,and north finding,the most critical parameters are identified,distinguishing suitable and unsuitable sensor choices.Special emphasis is placed on inertial navigation systems,where practical rules of thumb for error evaluation are derived using six degrees of freedom motion equations.Rigorous simulations demonstrate the influence of various sensor parameters through real-world case studies,including static navigation,multi-rotor attitude estimation,gimbal stabilization,and north finding via a turntable.This work aims to be a beacon for practitioners across diverse fields,empowering them to make more informed design decisions. 展开更多
关键词 Micro-electromechanical system Inertial measurement unit Calibration Sensor fusion GUIDANCE precision navigation Active disturbance rejection control Attitude and heading reference system
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AI-driven integration of multi-omics and multimodal data for precision medicine
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作者 Heng-Rui Liu 《Medical Data Mining》 2026年第1期1-2,共2页
High-throughput transcriptomics has evolved from bulk RNA-seq to single-cell and spatial profiling,yet its clinical translation still depends on effective integration across diverse omics and data modalities.Emerging ... High-throughput transcriptomics has evolved from bulk RNA-seq to single-cell and spatial profiling,yet its clinical translation still depends on effective integration across diverse omics and data modalities.Emerging foundation models and multimodal learning frameworks are enabling scalable and transferable representations of cellular states,while advances in interpretability and real-world data integration are bridging the gap between discovery and clinical application.This paper outlines a concise roadmap for AI-driven,transcriptome-centered multi-omics integration in precision medicine(Figure 1). 展开更多
关键词 high throughput transcriptomics multi omics single cell multimodal learning frameworks foundation models omics data modalitiesemerging ai driven precision medicine
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Harnessing CD146-positive mesenchymal stromal cells for precision therapy in acute respiratory distress syndrome
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作者 Özlem Tomsuk 《World Journal of Stem Cells》 2026年第1期1-7,共7页
Acute respiratory distress syndrome(ARDS)is a life-threatening condition that is characterized by high mortality rates and limited therapeutic options.Notably,Zhang et al demonstrated that CD146+mesenchymal stromal ce... Acute respiratory distress syndrome(ARDS)is a life-threatening condition that is characterized by high mortality rates and limited therapeutic options.Notably,Zhang et al demonstrated that CD146+mesenchymal stromal cells(MSCs)exhibited greater therapeutic efficacy than CD146-MSCs.These cells enhance epithelial repair through nuclear factor kappa B/cyclooxygenase-2-associated paracrine signaling and secretion of pro-angiogenic factors.We concur that MSCs hold significant promise for ARDS treatment;however,the heterogeneity of cell products is a translational barrier.Phenotype-aware strategies,such as CD146 enrichment,standardized potency assays,and extracellular vesicle profiling,are essential for improving the consistency of these studies.Further-more,advanced preclinical models,such as lung-on-a-chip systems,may provide more predictive insights into the therapeutic mechanisms.This article underscores the importance of CD146+MSCs in ARDS,emphasizes the need for precision in defining cell products,and discusses how integrating subset selection into translational pipelines could enhance the clinical impact of MSC-based therapies. 展开更多
关键词 Acute respiratory distress syndrome Mesenchymal stromal cells CD146 Nuclear factor kappa B/cyclooxygenase-2 signaling pathway Extracellular vesicles Endothelial barrier repair precision medicine
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PRECISION OF HSK TOOLING SYSTEM IN HIGH SPEED MACHINING 被引量:1
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作者 王贵成 吴卫国 +2 位作者 王树林 裴宏杰 沈春根 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第2期129-133,共5页
Based on the theory of elastic mechanics and material mechanics, the orientation precision of the hohl schaft kegel(HSK) tooling system in static and dynamic states is theoretically and experimentally studied. The r... Based on the theory of elastic mechanics and material mechanics, the orientation precision of the hohl schaft kegel(HSK) tooling system in static and dynamic states is theoretically and experimentally studied. The relation between the clamping force and the shank taper is obtained. And a proper clamping force is found to be essential to assure the axial and radial orientation precisions of the HSK tooling system in high speed machining (HSM). Analytical results show that the reason why the HSK tooling system can keep high precision at the high rotational speed is that the actual axial clamping force keeps the two surfaces of the shank and the spindle in contact all the time. 展开更多
关键词 high speed machining HSK tooling system orientation precision
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Research and Application of Maize Precision Intelligence Spatial Decision Support System
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作者 王国伟 陈桂芬 +1 位作者 姚玉霞 闫丽 《Agricultural Science & Technology》 CAS 2010年第6期147-151,188,共6页
In order to solve the problem of the maze precision fertilizer,soil fertility evaluation,soil fertility classify and yield projections,the geographic information system with spatial information processing functions,sp... In order to solve the problem of the maze precision fertilizer,soil fertility evaluation,soil fertility classify and yield projections,the geographic information system with spatial information processing functions,spatial data mining techniques with spatial information analysis capabilities,expert system technology in the field of artificial intelligence,traditional information management systems and decision support system were effectively integrated in this study,and the statistical analysis method of GIS and data visualization were combined to design and implement the maize precise intelligent space decision-making system.This system had greatly improved the decision-making ability in agricultural production carried out by agricultural management. 展开更多
关键词 Maize precision operation Space data mining Decision support system Geographic information system VISUALIZATION
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Pesticide Deinsectization System in Precision Agriculture Based on ARM-Linux
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作者 万厚冲 《Plant Diseases and Pests》 CAS 2010年第3期28-30,共3页
With precision agriculture as the base line, using embedded system as technical support, a set of ideas is proposed for solving the serious pesticide poisoning problem, including farmland information collection, exper... With precision agriculture as the base line, using embedded system as technical support, a set of ideas is proposed for solving the serious pesticide poisoning problem, including farmland information collection, experts database analysis and variable pesticide spraying, etc. 展开更多
关键词 precision agriculture ARM-LINUX PESTICIDE PEST SPRAYING
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Auto-normalization algorithm for robotic precision drilling system in aircraft component assembly 被引量:37
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作者 Tian Wei Zhou Weixue +2 位作者 Zhou Wei Liao Wenhe Zeng Yuanfan 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第2期495-500,共6页
A novel approach is proposed to detect the normal vector to product surface in real time for the robotic precision drilling system in aircraft component assembly, and the auto-normalization algorithm is presented base... A novel approach is proposed to detect the normal vector to product surface in real time for the robotic precision drilling system in aircraft component assembly, and the auto-normalization algorithm is presented based on the detection system. Firstly, the deviation between the normal vector and the spindle axis is measured by the four laser displacement sensors installed at the head of the multi-function end effector. Then, the robot target attitude is inversely solved according to the auto-normalization algorithm. Finally, adjust the robot to the target attitude via pitch and yaw rotations about the tool center point and the spindle axis is corrected in line with the normal vector simultaneously. To test and verify the auto-normalization algorithm, an experimental platform is established in which the laser tracker is introduced for accurate measurement. The results show that the deviations between the corrected spindle axis and the normal vector are all reduced to less than 0.5°, with the mean value 0.32°. It is demonstrated the detection method and the autonormalization algorithm are feasible and reliable. 展开更多
关键词 Aircraft assembly Auto-normalization Industrial robots Normal vector detection Robotic precision drilling
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Precision phenotyping of contrasting potato(Solanum tuberosum L.) varieties in a novel aeroponics system for improving nitrogen use efficiency: In search of key traits and genes 被引量:3
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作者 Jagesh K.TIWARI Sapna DEVI +5 位作者 Tanuja BUCKSETH Nilofer ALI Rajesh K.SINGH Rasna ZINTA Vijay K.DUA Swarup K.CHAKRABARTI 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第1期51-61,共11页
With increasing population, degrading soil health, limited arable land area, and high cost of nitrogen(N) fertilizers, improving nitrogen use efficiency(NUE) of potato is an inevitable approach to save the environment... With increasing population, degrading soil health, limited arable land area, and high cost of nitrogen(N) fertilizers, improving nitrogen use efficiency(NUE) of potato is an inevitable approach to save the environment and achieve sufficient tuber yields with less N fertilizer supply. Recently, we have developed an aeroponics system to study NUE in potato using genomics, physiology, and breeding approaches. This study aims on precision phenotyping of plants of two distinct potato varieties(Kufri Gaurav, N efficient;Kufri Jyoti, N inefficient) in the novel aeroponics system. Plants were grown in aeroponics under controlled conditions with low N(0.75 mmol L^-1NO3^-) and high N(7.5 mmol L^-1NO3^-) levels. Plant biomass, root traits, total chlorophyll content, and plant N were increased with increasing N supply, whereas higher NUE parameters namely NUE, agronomic NUE(Ag NUE), N uptake efficiency(NUp E), harvest index(HI), and N harvest index(NHI) were observed at low N. An NUE efficient cv. Kufri Gaurav showed higher tuber dry weight, fresh tuber yield, tuber number per plant, early start of tuber harvesting, root traits, stolon traits, NUE parameters, and higher amino acid(aspartic acid and asparagine) content at low N supply. Higher expression of nitrate reductase(NR), nitrite reductase(NIR), and asparagine synthetase(AS) genes was observed in the leaf tissues of Kufri Gaurav at high N. Thus, aeroponics-based precision phenotyping enables identification of NUE efficient genotypes based on key traits and genes involved in improving NUE in potato. Further, this study suggests that the potential of aeroponics can be utilized to investigate N biology in potato under different N regimes. 展开更多
关键词 AEROPONICS precision phenotyping POTATO nitrogen use efficiency
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Real-Time Iterative Compensation Framework for Precision Mechatronic Motion Control Systems 被引量:2
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作者 Chuxiong Hu Ran Zhou +2 位作者 Ze Wang Yu Zhu Masayoshi Tomizuka 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第7期1218-1232,共15页
With regard to precision/ultra-precision motion systems,it is important to achieve excellent tracking performance for various trajectory tracking tasks even under uncertain external disturbances.In this paper,to overc... With regard to precision/ultra-precision motion systems,it is important to achieve excellent tracking performance for various trajectory tracking tasks even under uncertain external disturbances.In this paper,to overcome the limitation of robustness to trajectory variations and external disturbances in offline feedforward compensation strategies such as iterative learning control(ILC),a novel real-time iterative compensation(RIC)control framework is proposed for precision motion systems without changing the inner closed-loop controller.Specifically,the RIC method can be divided into two parts,i.e.,accurate model prediction and real-time iterative compensation.An accurate prediction model considering lumped disturbances is firstly established to predict tracking errors at future sampling times.In light of predicted errors,a feedforward compensation term is developed to modify the following reference trajectory by real-time iterative calculation.Both the prediction and compen-sation processes are finished in a real-time motion control sampling period.The stability and convergence of the entire control system after real-time iterative compensation is analyzed for different conditions.Various simulation results consistently demonstrate that the proposed RIC framework possesses satisfactory dynamic regulation capability,which contributes to high tracking accuracy comparable to ILC or even better and strong robustness. 展开更多
关键词 precision motion control prediction model real-time iterative compensation trajectory tracking
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Design of Machine Learning Based Smart Irrigation System for Precision Agriculture 被引量:2
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作者 Khalil Ibrahim Mohammad Abuzanouneh Fahd N.Al-Wesabi +6 位作者 Amani Abdulrahman Albraikan Mesfer Al Duhayyim M.Al-Shabi Anwer Mustafa Hilal Manar Ahmed Hamza Abu Sarwar Zamani K.Muthulakshmi 《Computers, Materials & Continua》 SCIE EI 2022年第7期109-124,共16页
Agriculture 4.0,as the future of farming technology,comprises numerous key enabling technologies towards sustainable agriculture.The use of state-of-the-art technologies,such as the Internet of Things,transform tradit... Agriculture 4.0,as the future of farming technology,comprises numerous key enabling technologies towards sustainable agriculture.The use of state-of-the-art technologies,such as the Internet of Things,transform traditional cultivation practices,like irrigation,to modern solutions of precision agriculture.To achieve effectivewater resource usage and automated irrigation in precision agriculture,recent technologies like machine learning(ML)can be employed.With this motivation,this paper design an IoT andML enabled smart irrigation system(IoTML-SIS)for precision agriculture.The proposed IoTML-SIS technique allows to sense the parameters of the farmland and make appropriate decisions for irrigation.The proposed IoTML-SIS model involves different IoT based sensors for soil moisture,humidity,temperature sensor,and light.Besides,the sensed data are transmitted to the cloud server for processing and decision making.Moreover,artificial algae algorithm(AAA)with least squares-support vector machine(LS-SVM)model is employed for the classification process to determine the need for irrigation.Furthermore,the AAA is applied to optimally tune the parameters involved in the LS-SVM model,and thereby the classification efficiency is significantly increased.The performance validation of the proposed IoTML-SIS technique ensured better performance over the compared methods with the maximum accuracy of 0.975. 展开更多
关键词 Automatic irrigation precision agriculture smart farming machine learning cloud computing decision making internet of things
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Data-driven Nonparametric Model Adaptive Precision Control for Linear Servo Systems 被引量:2
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作者 Rong-Min Cao Zhong-Sheng Hou Hui-Xing Zhou 《International Journal of Automation and computing》 EI CSCD 2014年第5期517-526,共10页
Nowadays, high-precision motion controls are needed in modern manufacturing industry. A data-driven nonparametric model adaptive control(NMAC) method is proposed in this paper to control the position of a linear servo... Nowadays, high-precision motion controls are needed in modern manufacturing industry. A data-driven nonparametric model adaptive control(NMAC) method is proposed in this paper to control the position of a linear servo system. The controller design requires no information about the structure of linear servo system, and it is based on the estimation and forecasting of the pseudo-partial derivatives(PPD) which are estimated according to the voltage input and position output of the linear motor. The characteristics and operational mechanism of the permanent magnet synchronous linear motor(PMSLM) are introduced, and the proposed nonparametric model control strategy has been compared with the classic proportional-integral-derivative(PID) control algorithm. Several real-time experiments on the motion control system incorporating a permanent magnet synchronous linear motor showed that the nonparametric model adaptive control method improved the system s response to disturbances and its position-tracking precision, even for a nonlinear system with incompletely known dynamic characteristics. 展开更多
关键词 Data-driven control nonparametric model adaptive control precision motion control permanent magnet synchronous linear motor ROBUSTNESS
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Precision motion control for electro-hydraulic axis systems under unknown time-variant parameters and disturbances 被引量:1
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作者 Xiaowei YANG Yaowen GE +1 位作者 Wenxiang DENG Jianyong YAO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第1期463-471,共9页
This article focuses on asymptotic precision motion control for electro-hydraulic axis systems under unknown time-variant parameters,mismatched and matched disturbances.Different from the traditional adaptive results ... This article focuses on asymptotic precision motion control for electro-hydraulic axis systems under unknown time-variant parameters,mismatched and matched disturbances.Different from the traditional adaptive results that are applied to dispose of unknown constant parameters only,the unique feature is that an adaptive-gain nonlinear term is introduced into the control design to handle unknown time-variant parameters.Concurrently both mismatched and matched disturbances existing in electro-hydraulic axis systems can also be addressed in this way.With skillful integration of the backstepping technique and the adaptive control,a synthesized controller framework is successfully developed for electro-hydraulic axis systems,in which the coupled interaction between parameter estimation and disturbance estimation is avoided.Accordingly,this designed controller has the capacity of low-computation costs and simpler parameter tuning when compared to the other ones that integrate the adaptive control and observer/estimator-based technique to dividually handle parameter uncertainties and disturbances.Also,a nonlinear filter is designed to eliminate the“explosion of complexity”issue existing in the classical back-stepping technique.The stability analysis uncovers that all the closed-loop signals are bounded and the asymptotic tracking performance is also assured.Finally,contrastive experiment results validate the superiority of the developed method as well. 展开更多
关键词 Adaptive control Asymptotic convergence Electro-hydraulic axis system precision motion control Unknown time-variant parameters and disturbances
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A Large Range Flexure-Based Servo System Supporting Precision Additive Manufacturing 被引量:1
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作者 Zhen Zhang Peng Yan Guangbo Hao 《Engineering》 SCIE EI 2017年第5期708-715,共8页
This paper presents the design, development, and control of a large range beam flexure-based nano servo system for the micro-stereolithography (MSL) process. As a key enabler of high accuracy in this process, a comp... This paper presents the design, development, and control of a large range beam flexure-based nano servo system for the micro-stereolithography (MSL) process. As a key enabler of high accuracy in this process, a compact desktop-size beam flexure-based nanopositioner was designed with millimeter range and nanometric motion quality. This beam flexure-based motion system is highly suitable for harsh operation conditions, as no assembly or maintenance is required during the operation. From a mechanism design viewpoint, a mirror-symmetric arrangement and appropriate redundant constraints are crucial to reduce undesired parasitic motion. Detailed finite element analysis (FEA) was conducted and showed satisfactory mechanical features. With the identified dynamic models of the nanopositioner, real-time control strategies were designed and implemented into the monolithically fabricated prototype system, demonstrating the enhanced tracking capability of the MSL process. The servo system has both a millimeter operating range and a root mean square (RMS) tracking error of about 80 nm for a circular traiectorv. 展开更多
关键词 precision additive manufacturing Micro-stereolithography NANOPOSITIONING Beam flexure
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Error compensation on precision machine tool servo control system based on digital concave filter 被引量:1
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作者 王立松 苏宝库 +1 位作者 张晶 董申 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第4期389-393,共5页
It is concluded from the results of testing the frequency characteristics of the sub micron precision machine tool servo control system, that the existence of several oscillating modalities is the main factor that aff... It is concluded from the results of testing the frequency characteristics of the sub micron precision machine tool servo control system, that the existence of several oscillating modalities is the main factor that affects the performance of the control system. To compensate for this effect,several concave filters are utilized in the system to improve the control accuracy. The feasibility of compensating for several oscillating modalities with a single concave filter is also studied. By applying a modified Butterworth concave filter to the practical system, the maximum stable state output error remains under ±10 nm in the closed loop positioning system. 展开更多
关键词 precision machine tool concave filter oscillating modality
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