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A Corpus-Based Analysis of Verb Collocations in Human and AI-Generated IELTS Writing
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作者 Meirong Du Min Lu +1 位作者 Yi Dai Fan Wang 《教育技术与创新》 2025年第2期67-80,共14页
In this study,it aims at examining the differences between humangenerated and AI-generated texts in IELTS Writing Task 2.It especially focuses on lexical resourcefulness,grammatical accuracy,and contextual appropriate... In this study,it aims at examining the differences between humangenerated and AI-generated texts in IELTS Writing Task 2.It especially focuses on lexical resourcefulness,grammatical accuracy,and contextual appropriateness.We analyzed 20 essays,including 10 human written ones by Chinese university students who have achieved an IELTS writing score ranging from 5.5 to 6.0,and 10 ChatGPT-4 Turbo-generated ones,using a mixed-methods approach,through corpus-based tools(NLTK,SpaCy,AntConc)and qualitative content analysis.Results showed that AI texts exhibited superior grammatical accuracy(0.4%–3%error rates for AI vs.20–26%for university students)but higher lexical repetition(17.2%to 23.25%for AI vs.17.68%for university students)and weaker contextual adaptability(3.33/10–3.69/10 for AI vs.3.23/10 to 4.14/10 for university students).While AI’s grammatical precision supports its utility as a corrective tool,human writers outperformed AI in lexical diversity and task-specific nuance.The findings advocate for a hybrid pedagogical model that leverages AI’s strengths in error detection while retaining human instruction for advanced lexical and contextual skills.Limitations include the small corpus and single-AI-model focus,suggesting future research with diverse datasets and longitudinal designs. 展开更多
关键词 ai-generated writing IELTS Writing Task 2 verb collocations
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Upholding Academic Integrity amidst Advanced Language Models: Evaluating BiLSTM Networks with GloVe Embeddings for Detecting AI-Generated Scientific Abstracts
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作者 Lilia-Eliana Popescu-Apreutesei Mihai-Sorin Iosupescu +1 位作者 Sabina Cristiana Necula Vasile-Daniel Pavaloaia 《Computers, Materials & Continua》 2025年第8期2605-2644,共40页
The increasing fluency of advanced language models,such as GPT-3.5,GPT-4,and the recently introduced DeepSeek,challenges the ability to distinguish between human-authored and AI-generated academic writing.This situati... The increasing fluency of advanced language models,such as GPT-3.5,GPT-4,and the recently introduced DeepSeek,challenges the ability to distinguish between human-authored and AI-generated academic writing.This situation is raising significant concerns regarding the integrity and authenticity of academic work.In light of the above,the current research evaluates the effectiveness of Bidirectional Long Short-TermMemory(BiLSTM)networks enhanced with pre-trained GloVe(Global Vectors for Word Representation)embeddings to detect AIgenerated scientific Abstracts drawn from the AI-GA(Artificial Intelligence Generated Abstracts)dataset.Two core BiLSTM variants were assessed:a single-layer approach and a dual-layer design,each tested under static or adaptive embeddings.The single-layer model achieved nearly 97%accuracy with trainable GloVe,occasionally surpassing the deeper model.Despite these gains,neither configuration fully matched the 98.7%benchmark set by an earlier LSTMWord2Vec pipeline.Some runs were over-fitted when embeddings were fine-tuned,whereas static embeddings offered a slightly lower yet stable accuracy of around 96%.This lingering gap reinforces a key ethical and procedural concern:relying solely on automated tools,such as Turnitin’s AI-detection features,to penalize individuals’risks and unjust outcomes.Misclassifications,whether legitimate work is misread as AI-generated or engineered text,evade detection,demonstrating that these classifiers should not stand as the sole arbiters of authenticity.Amore comprehensive approach is warranted,one which weaves model outputs into a systematic process supported by expert judgment and institutional guidelines designed to protect originality. 展开更多
关键词 AI-GA dataset bidirectional LSTM GloVe embeddings ai-generated text detection academic integrity deep learning OVERFITTING natural language processing
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AI-Generated Content Tools and Chain of Thought:Revolutionizing Pragmatics and Translation Education for MTI Students
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作者 Mengyao Liu 《Journal of Contemporary Educational Research》 2025年第8期72-77,共6页
This conceptual study proposes a pedagogical framework that integrates Generative Artificial Intelligence tools(AIGC)and Chain-of-Thought(CoT)reasoning,grounded in the cognitive apprenticeship model,for the Pragmatics... This conceptual study proposes a pedagogical framework that integrates Generative Artificial Intelligence tools(AIGC)and Chain-of-Thought(CoT)reasoning,grounded in the cognitive apprenticeship model,for the Pragmatics and Translation course within Master of Translation and Interpreting(MTI)programs.A key feature involves CoT reasoning exercises,which require students to articulate their step-by-step translation reasoning.This explicates cognitive processes,enhances pragmatic awareness,translation strategy development,and critical reflection on linguistic choices and context.Hypothetical activities exemplify its application,including comparative analysis of AI and human translations to examine pragmatic nuances,and guided exercises where students analyze or critique the reasoning traces generated by Large Language Models(LLMs).Ethically grounded,the framework positions AI as a supportive tool,thereby ensuring human translators retain the central decision-making role and promoting critical evaluation of machine-generated suggestions.Potential challenges,such as AI biases,ethical concerns,and overreliance,are addressed through strategies including bias-awareness discussions,rigorous accuracy verification,and a strong emphasis on human accountability.Future research will involve piloting the framework to empirically evaluate its impact on learners’pragmatic competence and translation skills,followed by iterative refinements to advance evidence-based translation pedagogy. 展开更多
关键词 ai-generated Content(AIGC) Chain of Thought(CoT) Pragmatics and translation course MTI students Cognitive apprenticeship
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An Analysis of the Copyrightability of AI-Generated Images
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作者 Zheng Xianfang Xing Ziran 《Contemporary Social Sciences》 2024年第6期100-114,共15页
AI-generated images are a prime example of AI-generated content,and this paper discusses the controversy over their copyrightability.Starting with the general technical principles that lie behind AI’s deep learning f... AI-generated images are a prime example of AI-generated content,and this paper discusses the controversy over their copyrightability.Starting with the general technical principles that lie behind AI’s deep learning for model training and the generation and correction of AI-generated images according to an AI users’instructions to the AI prompt and their parameter settings,the paper analyzes the initial legal viewpoint that as AI-generated images do not have a human creator,they cannot apply for copyright.It goes on to examine the rapid development of AI-generated image technology and the gradual adoption of more open attitudes towards the copyrightability of AI-generated images due to the influence of the promoting technological advancement approach.On the basis of this,the paper further analyzes the criteria for assessing the copyrightability of AI-generated images,by using measures such as originality,human authorship,and intellectual achievements,aiming to clarify the legal basis for the copyrightability of AI-generated images and enhancing the copyright protection system. 展开更多
关键词 ai-generated content ai-generated image AIGC copyrightability COPYRIGHT
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HybridGAD: Identification of AI-Generated Radiology Abstracts Based on a Novel Hybrid Model with Attention Mechanism
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作者 TugbaÇelikten Aytug Onan 《Computers, Materials & Continua》 SCIE EI 2024年第8期3351-3377,共27页
Class Title:Radiological imaging method a comprehensive overview purpose.This GPT paper provides an overview of the different forms of radiological imaging and the potential diagnosis capabilities they offer as well a... Class Title:Radiological imaging method a comprehensive overview purpose.This GPT paper provides an overview of the different forms of radiological imaging and the potential diagnosis capabilities they offer as well as recent advances in the field.Materials and Methods:This paper provides an overview of conventional radiography digital radiography panoramic radiography computed tomography and cone-beam computed tomography.Additionally recent advances in radiological imaging are discussed such as imaging diagnosis and modern computer-aided diagnosis systems.Results:This paper details the differences between the imaging techniques the benefits of each and the current advances in the field to aid in the diagnosis of medical conditions.Conclusion:Radiological imaging is an extremely important tool in modern medicine to assist in medical diagnosis.This work provides an overview of the types of imaging techniques used the recent advances made and their potential applications. 展开更多
关键词 Generative artificial intelligence ai-generated text detection attention mechanism hybrid model for text classification
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A Verification Theorem for Feedback Nash Equilibrium in Multiple-Player Nonzero-Sum Impulse Game 被引量:1
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作者 Ruihai Li Yaoyao Tan +1 位作者 Xiaojie Su Jiangshuai Huang 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期648-650,共3页
Dear Editor,This letter addresses the impulse game problem for a general scope of deterministic,multi-player,nonzero-sum differential games wherein all participants adopt impulse controls.Our objective is to formulate... Dear Editor,This letter addresses the impulse game problem for a general scope of deterministic,multi-player,nonzero-sum differential games wherein all participants adopt impulse controls.Our objective is to formulate this impulse game problem with the modified objective function including interaction costs among the players in a discontinuous fashion,and subsequently,to derive a verification theorem for identifying the feedback Nash equilibrium strategy. 展开更多
关键词 impulse game feedback Nash equilibrium multiple player feedback nash equilibrium strategy impulse game problem nonzero sum modified objective function impulse controlsour
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An Empirical Study on the Reflective Feedback Model Based on Pedagogical Agents to Improve Students’ Problem-Solving Ability 被引量:1
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作者 Hui-Lin Zhang Jun-Jie Yan +4 位作者 Jing Liu Zhuo-Cen Zou Qun-Fang Zeng Yu-Lu Jin Jian-Nan Wu 《教育技术与创新》 2025年第1期66-75,共10页
This study constructs a reflective feedback model based on a pedagogical agent(PA)and explores its impact on students’problem-solving ability and cognitive load.A quasi-experimental design was used in the study,with ... This study constructs a reflective feedback model based on a pedagogical agent(PA)and explores its impact on students’problem-solving ability and cognitive load.A quasi-experimental design was used in the study,with 84 students from a middle school selected as the research subjects(44 in the experimental group and 40 in the control group).The experimental group used the reflective feedback model,while the control group used the factual feedback model.The results show that,compared with factual feedback,the reflective feedback model based on the pedagogical agent significantly improves students’problem-solving ability,especially at the action and thinking levels.In addition,this model effectively reduces students’cognitive load,especially in terms of internal and external load. 展开更多
关键词 pedagogical agent problem-solving ability reflective feedback
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A Research on Written Feedback in English Writing Course of English Majors
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作者 LIU Jun 《Sino-US English Teaching》 2025年第3期87-91,共5页
Written feedback in English writing classes serves as the primary mode of feedback.By comparing direct corrective feedback and indirect corrective feedback in addressing content and form,this paper argues that indirec... Written feedback in English writing classes serves as the primary mode of feedback.By comparing direct corrective feedback and indirect corrective feedback in addressing content and form,this paper argues that indirect corrective feedback better aligns with the needs of English majors.Multiple factors influence the choice of written feedback methods,and teachers should carefully select the most appropriate approach based on student characteristics to maximize the effectiveness of feedback. 展开更多
关键词 English writing written feedback indirect feedback corrective feedback
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The Efficacy of Written Corrective Feedback Explicitness on the Grammatical Accuracy of Passive Voice Tenses
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作者 Syed Muhammad Mujtaba Manjet Kaur Mehar Singh 《Chinese Journal of Applied Linguistics》 2025年第2期183-206,320,共25页
Although substantial research shows the effectiveness of written corrective feedback(WCF)in treating simple grammar structures,more research is still needed to refute Truscott’s claim that WCF may not work on complex... Although substantial research shows the effectiveness of written corrective feedback(WCF)in treating simple grammar structures,more research is still needed to refute Truscott’s claim that WCF may not work on complex grammar structures.Similarly,a previous body of research has shown that the degree of explicitness of feedback moderates the efficacy of WCF.However,most WCF studies have systematically manipulated only direct corrective feedback.The current study was therefore conducted to fill these gaps in the literature.To this end,five intact classes of Functional English were recruited and later randomly assigned to four treatment groups:DCF,DCF+ME,ICF,and ICF+ME,and one control group that received no feedback.All the groups took part in three WCF treatment sessions,during which they wrote two different pieces:a news report and a picture description.Later,only the treatment groups received the WCF.The WCF’s effectiveness was measured by writing tests and grammaticality judgment tasks(GJT).The results demonstrated that WCF helped L2 learners improve their grammatical accuracy of passive voice tenses.The study further showed that the group that received the most explicit type of WCF fared better than the ones that received the least explicit type of WCF.Important pedagogical implications for ESL/EFL teachers are discussed. 展开更多
关键词 written corrective feedback direct corrective feedback indirect corrective feedback metalinguistic explanation passive voice
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Coherent feedback ground-state cooling of mechanical resonators assisted by a quantum well
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作者 Qinghong Liao Songyun Ouyang +1 位作者 Shaoping Cheng Yiping Cheng 《Chinese Physics B》 2025年第4期405-411,共7页
We theoretically investigate a cooling scheme assisted by a quantum well(QW)and coherent feedback within a hybrid optomechanical system.Although the exciton mode in the QW and the mechanical resonator(MR)are initially... We theoretically investigate a cooling scheme assisted by a quantum well(QW)and coherent feedback within a hybrid optomechanical system.Although the exciton mode in the QW and the mechanical resonator(MR)are initially uncoupled,their interaction via the microcavity field leads to an indirect exciton-mode–mechanical-mode coupling.The coherent feedback loop is applied by feeding back a fraction of the output field of the cavity through a controllable beam splitter to the cavity’s input mirror.It is shown that the cooling capability is enhanced by effectively suppressing the Stokes process through coupling with the QW.Furthermore,the effect of the anti-Stokes process is enhanced through the application of the coherent feedback loop.This particular system configuration enables cooling of the mechanical resonator even in the unresolved sideband regime(USR).This study has some important guiding significance in the field of quantum information processing. 展开更多
关键词 ground-state cooling quantum well coherent feedback optomechanical system
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A haptic feedback glove for virtual piano interaction
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作者 Yifan FU Jialin LIU +1 位作者 Xu LI Xiaoying SUN 《虚拟现实与智能硬件(中英文)》 2025年第1期95-110,共16页
Background Haptic feedback plays a crucial role in virtual reality(VR)interaction,helping to improve the precision of user operation and enhancing the immersion of the user experience.Instrumental haptic feedback in v... Background Haptic feedback plays a crucial role in virtual reality(VR)interaction,helping to improve the precision of user operation and enhancing the immersion of the user experience.Instrumental haptic feedback in virtual environments is primarily realized using grounded force or vibration feedback devices.However,improvements are required in terms of the active space and feedback realism.Methods We propose a lightweight and flexible haptic feedback glove that can haptically render objects in VR environments via kinesthetic and vibration feedback,thereby enabling users to enjoy a rich virtual piano-playing experience.The kinesthetic feedback of the glove relies on a cable-pulling mechanism that rotates the mechanism and pulls the two cables connected to it,thereby changing the amount of force generated to simulate the hardness or softness of the object.Vibration feedback is provided by small vibration motors embedded in the bottom of the fingertips of the glove.We designed a piano-playing scenario in the virtual environment and conducted user tests.The evaluation metrics were clarity,realism,enjoyment,and satisfaction.Results A total of 14 subjects participated in the test,and the results showed that our proposed glove scored significantly higher on the four evaluation metrics than the nofeedback and vibration feedback methods.Conclusions Our proposed glove significantly enhances the user experience when interacting with virtual objects. 展开更多
关键词 Wearable device Human-computer interaction Virtual reality Haptic feedback
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Control Structures and Algorithms for Force Feedback Bilateral Teleoperation Systems: A Comprehensive Review
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作者 Jiawei Tian Yu Zhou +5 位作者 Lirong Yin Salman A.AlQahtani Minyi Tang Siyu Lu Ruiyang Wang Wenfeng Zheng 《Computer Modeling in Engineering & Sciences》 2025年第2期973-1019,共47页
Force feedback bilateral teleoperation represents a pivotal advancement in control technology,finding widespread application in hazardous material transportation,perilous environments,space and deep-sea exploration,an... Force feedback bilateral teleoperation represents a pivotal advancement in control technology,finding widespread application in hazardous material transportation,perilous environments,space and deep-sea exploration,and healthcare domains.This paper traces the evolutionary trajectory of force feedback bilateral teleoperation from its conceptual inception to its current complexity.It elucidates the fundamental principles underpinning interaction forces and tactile exchanges,with a specific emphasis on the crucial role of tactile devices.In this review,a quantitative analysis of force feedback bilateral teleoperation development trends from 2011 to 2024 has been conducted,utilizing published journal article data as the primary source of information.The review accentuates classical control frameworks and algorithms,while also delving into existing research advancements and prospec-tive breakthrough directions.Moreover,it explores specific practical scenarios ranging from intricate surgeries to hazardous environment exploration,underscoring the technology’s potential to revolutionize industries by augmenting human manipulation of remote systems.This underscores the pivotal role of force feedback bilateral teleoperation as a transformative human-machine interface,capable of shaping flexible control strategies and addressing technological bottlenecks.Future research endeavors in force feedback bilateral teleoperation are expected to prioritize the creation of more immersive experiences,overcoming technical hurdles,fortifying human-machine collaboration,and broadening application domains,particularly within the realms of medical intervention and hazardous environments.With the continuous progression of technology,the integration of human intelligence and robotic capabilities is expected to produce more innovations and breakthroughs in the field of automatic control. 展开更多
关键词 Force feedback bilateral teleoperation ROBOT development history APPLICATION PROSPECT
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Limited Feedback in RIS-Assisted Wireless Communications: Use Cases, Challenges, and Future Directions
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作者 Chen Weicong Guo Jiajia +2 位作者 Cui Yiming Li Xiao Jin Shi 《China Communications》 2025年第10期238-250,共13页
Channel state information(CSI)is essen-tial to unlock the potential of reconfigurable intelli-gent surfaces(RISs)in wireless communication sys-tems.Since massive RIS elements are typically imple-mented without baseban... Channel state information(CSI)is essen-tial to unlock the potential of reconfigurable intelli-gent surfaces(RISs)in wireless communication sys-tems.Since massive RIS elements are typically imple-mented without baseband signal processing capabili-ties,limited CSI feedback is necessary when design-ing the reflection/refraction coefficients of the RIS.In this article,the unique RIS-assisted channel features,such as the RIS position-dependent channel fluctua-tion,the ultra-high dimensional sub-channel matrix,and the structured sparsity,are distilled from recent advances in limited feedback and used as guidelines for designing feedback schemes.We begin by il-lustrating the use cases and the corresponding chal-lenges associated with RIS feedback.We then discuss how to leverage techniques such as channel customiza-tion,structured-sparsity,autoencoders,and others to reduce feedback overhead and complexity when de-vising feedback schemes.Finally,we identify poten-tial research directions by considering the unresolved challenges,the new RIS architecture,and the integra-tion with multi-modal information and artificial intel-ligence. 展开更多
关键词 channel characteristic limited feedback reconfigurable intelligent surface
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Differential Vegetation Feedback on the Global Land Monsoon System during the Mid-Holocene and Last Interglacial
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作者 Zhenqian WANG Qiong ZHANG +1 位作者 Jie CHEN Zixuan HAN 《Advances in Atmospheric Sciences》 2026年第1期103-119,共17页
This study investigates the impact of vegetation-climate feedback on the global land monsoon system during the Last Interglacial(LIG,127000 years BP)and the mid-Holocene(MH,6000 years BP)using the earth system model E... This study investigates the impact of vegetation-climate feedback on the global land monsoon system during the Last Interglacial(LIG,127000 years BP)and the mid-Holocene(MH,6000 years BP)using the earth system model EC-Earth3.Our findings indicate that vegetation changes significantly influence the global monsoon area and precipitation patterns,especially in the North African and Indian monsoon regions.The North African monsoon region experienced the most substantial increase in vegetation during both the LIG and MH,resulting in significant increases in monsoonal precipitation by 9.8%and 6.0%,respectively.The vegetation feedback also intensified the Saharan Heat Low,strengthened monsoonal flows,and enhanced precipitation over the North African monsoon region.In contrast,the Indian monsoon region exhibited divergent responses to vegetation changes.During the LIG,precipitation in the Indian monsoon region decreased by 2.2%,while it increased by 1.6%during the MH.These differences highlight the complex and region-specific impacts of vegetation feedback on monsoon systems.Overall,this study demonstrates that vegetation feedback exerts distinct influences on the global monsoon during the MH and LIG.These findings highlight the importance of considering vegetation-climate feedback in understanding past monsoon variability and in predicting future climate change impacts on monsoon systems. 展开更多
关键词 Last Interglacial MID-HOLOCENE global land monsoon vegetation feedback
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Nonlinear Resonance Response of Suspended Cables Under Multi-Frequency Excitations and Time-Delayed Feedback
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作者 Jian Peng Hui Xia +2 位作者 Lianhua Wang Xiaoyu Zhang Xianzhong Xie 《Acta Mechanica Solida Sinica》 2025年第4期689-700,共12页
This study investigates the nonlinear resonance responses of suspended cables subjected to multi-frequency excitations and time-delayed feedback.Two specific combinations and simultaneous resonances are selected for d... This study investigates the nonlinear resonance responses of suspended cables subjected to multi-frequency excitations and time-delayed feedback.Two specific combinations and simultaneous resonances are selected for detailed examination.Initially,utilizing Hamilton’s variational principle,a nonlinear vibration control model of suspended cables under multi-frequency excitations and longitudinal time-delayed velocity feedback is developed,and the Galerkin method is employed to obtain the discrete model.Subsequently,focusing solely on single-mode discretization,analytical solutions for the two simultaneous resonances are derived using the method of multiple scales.The frequency response equations are derived,and the stability analysis is presented for two simultaneous resonance cases.The results demonstrate that suspended cables exhibit complex nonlinearity under multi-frequency excitations.Multiple solutions under multi-frequency excitation can be distinguished through the frequency–response and the detuning-phase curves.By adjusting the control gain and time delay,the resonance range,response amplitude,and phase of suspended cables can be modified. 展开更多
关键词 Suspended cables Multi-frequency excitation Time-delayed feedback Nonlinear resonance response
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Design and verification of a new multiharmonic feedback control system for CSNS-II RCS
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作者 Jian Wu Xiang Li +8 位作者 Bin Wu Yang Liu Chun-Lin Zhang Wei Long Jun-Yu Zhu Sheng-Hua Liu Zhi-Jun Lu Sheng-Yi Chen Xiao Li 《Nuclear Science and Techniques》 2025年第4期82-91,共10页
A dual-harmonic acceleration system is utilized to mitigate the space-charge effect in the rapid-cycling synchrotron of the China Spallation Neutron Source upgrade project(CSNS-II).A magnetic alloy(MA)-loaded cavity w... A dual-harmonic acceleration system is utilized to mitigate the space-charge effect in the rapid-cycling synchrotron of the China Spallation Neutron Source upgrade project(CSNS-II).A magnetic alloy(MA)-loaded cavity with a high accelerating gradient is developed to satisfy the requirements of dual-harmonic acceleration and provide the necessary second-harmonic cavity voltage.However,the MA-loaded cavity exhibits a wideband frequency response,resulting in numerous higher harmonics in the radio-frequency(RF)voltage.These higher harmonics are caused by both the beam-loading effect and distorted amplifier current,which distort the RF bucket,increase the power dissipation in the cavity,and lower the gradient.To address these issues,a multiharmonic independent feedback-control approach is implemented to compensate for higher harmonics.The effectiveness of this control strategy is validated experimentally.This study provides details regarding the feedback-control design and presents the commissioning results. 展开更多
关键词 MA-loaded cavity Beam-loading effect Multiharmonic independent feedback control
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Identification and compensation of friction and force ripple in PMSLM based on the time-domain analysis of relay feedback
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作者 Xiang Zhang Fuzhao Chen +3 位作者 Qian Chen Yongjing Ma Xiuwei Tong Zhenhong Wang 《Railway Sciences》 2025年第4期475-493,共19页
Purpose–This study aims to propose a novel identification method to accurately estimate linear and nonlinear dynamics in permanent magnet synchronous linear motor(PMSLM)based on the time-domain analysis of relay feed... Purpose–This study aims to propose a novel identification method to accurately estimate linear and nonlinear dynamics in permanent magnet synchronous linear motor(PMSLM)based on the time-domain analysis of relay feedback.Design/methodology/approach–A mathematical model of the PMSLM-based servo-mechanical system was first established,incorporating the aforementioned nonlinearities.The model’s velocity response was derived by analyzing its behavior as a first-order system under arbitrary input.To induce oscillatory dynamics,an ideal relay with artificially introduced dead-time components was then integrated into the servo-mechanism.Depending on the oscillations and the time-domain analysis,nonlinear formulas were deduced according to the velocity response of the servo-mechanism.Afterwards,the unknown model parameters can be solved on account of the cost function which utilizes the discrepancy between nominal position characteristics and temporary position characteristics,both of which are extracted from the oscillations.The proposed recognition method was validated through a twostage process:(1)numerical simulation and calculation,followed by(2)real-time experimental verification on a direct-drive servo platform.Subsequently,leveraging the identification results,a novel control strategy was developed and its tracking performance was benchmarked against conventional control schemes.Findings–Simulation results demonstrate that the proposed method achieves estimation accuracy within 8%.Building on this,a novel control strategy is developed by incorporating both friction pulsation and force pulsation identification results into the feedforward compensator.Comparative experiments reveal that this strategy significantly enhances tracking and positioning performance over traditional control schemes.In a word,this new identification method can be used in different process control and servo control systems.Moreover,parameter auto-tuning,feed forward compensation or disturbance observer can be investigated based on the obtained information to improve the system stability and control accuracy.Originality/value–It is of great significance for the performance improvement of rail transit motor control equipment,such as electro-mechanical braking systems.By enhancing the efficiency of motor control,the performance of the product will be more outstanding. 展开更多
关键词 Motor control PMSLM Relay feedback Force ripple FRICTION Relay parameters
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Phenological control of vegetation biophysical feedbacks to the regional climate
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作者 Lingxue Yu Ye Liu +4 位作者 Fengqin Yan Lijie Lu Xuan Li Shuwen Zhang Jiuchun Yang 《Geography and Sustainability》 2025年第1期223-237,共15页
Phenology shifts influence regional climate by altering energy,and water fluxes through biophysical processes.However,a quantitative understanding of the phenological control on vegetation’s biophysical feedbacks to ... Phenology shifts influence regional climate by altering energy,and water fluxes through biophysical processes.However,a quantitative understanding of the phenological control on vegetation’s biophysical feedbacks to re gional climate remains elusive.Using long-term remote sensing observations and Weather Research and Fore casting(WRF)model simulations,we investigated vegetation phenology changes from 2003 to 2020 and quan tified their biophysical controls on the regional climate in Northeast China.Our findings elucidated that earlier green-up contributed to a prolonged growing season in forests,while advanced green-up and delayed dormancy extended the growing season in croplands.This prolonged presence and increased maximum green cover in tensified climate-vegetation interactions,resulting in more significant surface cooling in croplands compared to forests.Surface cooling from forest phenology changes was prominent during May’s green-up(-0.53±0.07°C),while crop phenology changes induced cooling throughout the growing season,particularly in June(-0.47±0.15°C),July(-0.48±0.11°C),and September(-0.28±0.09°C).Furthermore,we unraveled the contributions of different biophysical pathways to temperature feedback using a two-resistance attribution model,with aero dynamic resistance emerging as the dominant factor.Crucially,our findings underscored that the land surface temperature(LST)sensitivity,exhibited substantially higher values in croplands rather than temperate forests.These strong sensitivities,coupled with the projected continuation of phenology shifts,portend further growing season cooling in croplands.These findings contribute to a more comprehensive understanding of the intricate feedback mechanisms between vegetation phenology and surface temperature,emphasizing the significance of vegetation phenology dynamics in shaping regional climate pattern and seasonality. 展开更多
关键词 Phenology shifts Biophysical feedback Land-atmosphere interactions Regional climate simulation
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Global adaptive output feedback control of nonlinear time-delay systems with measurement uncertainty
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作者 Weiguo Cai Xianglei Jia Xinxu Ju 《Control Theory and Technology》 2025年第1期145-152,共8页
In this paper,a pair of dynamic high-gain observer and output feedback controller is proposed for nonlinear systems with multiple unknown time delays.By constructing Lyapunov-Krasovskii functionals,it shows that globa... In this paper,a pair of dynamic high-gain observer and output feedback controller is proposed for nonlinear systems with multiple unknown time delays.By constructing Lyapunov-Krasovskii functionals,it shows that global state asymptotic regulation can be ensured by introducing a single dynamic gain;furthermore,global asymptotic stabilization can be achieved by choosing a sufficiently large static scaling gain when the upper bounds of all system parameters are known.Especially,the output coefficient is allowed to be non-differentiable with unknown upper bound.This paper proposes a generalized Lyapunov matrix inequality based dynamic-gain scaling method,which significantly simplifies the design computational complexity by comparing with the classic backstepping method. 展开更多
关键词 Output feedback Measurement uncertainty Nonlinear adaptive control Time delays
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