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A Regional Distribution Network Coordinated Optimization Strategy for Electric Vehicle Clusters Based on Parametric Deep Reinforcement Learning
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作者 Lei Su Wanli Feng +4 位作者 Cao Kan Mingjiang Wei Jihai Wang Pan Yu Lingxiao Yang 《Energy Engineering》 2026年第3期195-214,共20页
To address the high costs and operational instability of distribution networks caused by the large-scale integration of distributed energy resources(DERs)(such as photovoltaic(PV)systems,wind turbines(WT),and energy s... To address the high costs and operational instability of distribution networks caused by the large-scale integration of distributed energy resources(DERs)(such as photovoltaic(PV)systems,wind turbines(WT),and energy storage(ES)devices),and the increased grid load fluctuations and safety risks due to uncoordinated electric vehicles(EVs)charging,this paper proposes a novel dual-scale hierarchical collaborative optimization strategy.This strategy decouples system-level economic dispatch from distributed EV agent control,effectively solving the resource coordination conflicts arising from the high computational complexity,poor scalability of existing centralized optimization,or the reliance on local information decision-making in fully decentralized frameworks.At the lower level,an EV charging and discharging model with a hybrid discrete-continuous action space is established,and optimized using an improved Parameterized Deep Q-Network(PDQN)algorithm,which directly handles mode selection and power regulation while embedding physical constraints to ensure safety.At the upper level,microgrid(MG)operators adopt a dynamic pricing strategy optimized through Deep Reinforcement Learning(DRL)to maximize economic benefits and achieve peak-valley shaving.Simulation results show that the proposed strategy outperforms traditional methods,reducing the total operating cost of the MG by 21.6%,decreasing the peak-to-valley load difference by 33.7%,reducing the number of voltage limit violations by 88.9%,and lowering the average electricity cost for EV users by 15.2%.This method brings a win-win result for operators and users,providing a reliable and efficient scheduling solution for distribution networks with high renewable energy penetration rates. 展开更多
关键词 Power system regional distributed energy electric vehicle deep reinforcement learning collaborative optimization
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Synergistic machine learning and DFT screening strategy:Accelerating discovery of efficient perovskite passivators
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作者 Jianghao Liu Hongyan Lv +4 位作者 Pengyang Wang Guofu Hou Ying Zhao Xiaodan Zhang Qian Huang 《Journal of Energy Chemistry》 2026年第1期56-63,I0003,共9页
Efficient surface passivation is critical for achieving high-performance perovskite solar cells(PSCs),yet the discovery of optimal passivators remains a time-consuming,trial-and-error process.Here,we report a synergis... Efficient surface passivation is critical for achieving high-performance perovskite solar cells(PSCs),yet the discovery of optimal passivators remains a time-consuming,trial-and-error process.Here,we report a synergistic machine learning(ML)and density functional theory(DFT)approach that enables predictive and rapid identification of effective passivation materials.By training an XGBoost model(91.3%accuracy)with DFT-derived molecular descriptors and activity calculations,we identify 2-(4-aminophenyl)-3H-benzimidazol-5-amine(APBIA)as a promising passivator.Experimental validation demonstrates that APBIA effectively removes surface impurities and passivates defects within perovskite films,leading to a significant increase in power conversion efficiency(PCE)from 22.48%to 25.55%(certified as 25.02%).This ML-DFT framework provides a generalizable pathway for accelerating the development of advanced functional materials for photovoltaic applications. 展开更多
关键词 Perovskite solar cells Machine learning(ML) Density functional theory(DFT) Passivators Organic molecule
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FedCPS:A Dual Optimization Model for Federated Learning Based on Clustering and Personalization Strategy 被引量:1
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作者 Zhen Yang Yifan Liu +2 位作者 Fan Feng Yi Liu Zhenpeng Liu 《Computers, Materials & Continua》 2025年第4期357-380,共24页
Federated learning is a machine learning framework designed to protect privacy by keeping training data on clients’devices without sharing private data.It trains a global model through collaboration between clients a... Federated learning is a machine learning framework designed to protect privacy by keeping training data on clients’devices without sharing private data.It trains a global model through collaboration between clients and the server.However,the presence of data heterogeneity can lead to inefficient model training and even reduce the final model’s accuracy and generalization capability.Meanwhile,data scarcity can result in suboptimal cluster distributions for few-shot clients in centralized clustering tasks,and standalone personalization tasks may cause severe overfitting issues.To address these limitations,we introduce a federated learning dual optimization model based on clustering and personalization strategy(FedCPS).FedCPS adopts a decentralized approach,where clients identify their cluster membership locally without relying on a centralized clustering algorithm.Building on this,FedCPS introduces personalized training tasks locally,adding a regularization term to control deviations between local and cluster models.This improves the generalization ability of the final model while mitigating overfitting.The use of weight-sharing techniques also reduces the computational cost of central machines.Experimental results on MNIST,FMNIST,CIFAR10,and CIFAR100 datasets demonstrate that our method achieves better personalization effects compared to other personalized federated learning methods,with an average test accuracy improvement of 0.81%–2.96%.Meanwhile,we adjusted the proportion of few-shot clients to evaluate the impact on accuracy across different methods.The experiments show that FedCPS reduces accuracy by only 0.2%–3.7%,compared to 2.1%–10%for existing methods.Our method demonstrates its advantages across diverse data environments. 展开更多
关键词 Federated learning CLUSTER PERSONALIZATION OVERFITTING
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Multi-Objective Parallel Human-machine Steering Coordination Control Strategy of Intelligent Vehicles Path Tracking Based on Deep Reinforcement Learning 被引量:1
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作者 Hongbo Wang Lizhao Feng +2 位作者 Shaohua Li Wuwei Chen Juntao Zhou 《Chinese Journal of Mechanical Engineering》 2025年第3期393-411,共19页
In the parallel steering coordination control strategy for path tracking,it is difficult to match the current driver steering model using the fixed parameters with the actual driver,and the designed steering coordinat... In the parallel steering coordination control strategy for path tracking,it is difficult to match the current driver steering model using the fixed parameters with the actual driver,and the designed steering coordination control strategy under a single objective and simple conditions is difficult to adapt to the multi-dimensional state variables’input.In this paper,we propose a deep reinforcement learning algorithm-based multi-objective parallel human-machine steering coordination strategy for path tracking considering driver misoperation and external disturbance.Firstly,the driver steering mathematical model is constructed based on the driver preview characteristics and steering delay response,and the driver characteristic parameters are fitted after collecting the actual driver driving data.Secondly,considering that the vehicle is susceptible to the influence of external disturbances during the driving process,the Tube MPC(Tube Model Predictive Control)based path tracking steering controller is designed based on the vehicle system dynamics error model.After verifying that the driver steering model meets the driver steering operation characteristics,DQN(Deep Q-network),DDPG(Deep Deterministic Policy Gradient)and TD3(Twin Delayed Deep Deterministic Policy Gradient)deep reinforcement learning algorithms are utilized to design a multi-objective parallel steering coordination strategy which satisfies the multi-dimensional state variables’input of the vehicle.Finally,the tracking accuracy,lateral safety,human-machine conflict and driver steering load evaluation index are designed in different driver operation states and different road environments,and the performance of the parallel steering coordination control strategies with different deep reinforcement learning algorithms and fuzzy algorithms are compared by simulations and hardware in the loop experiments.The results show that the parallel steering collaborative strategy based on a deep reinforcement learning algorithm can more effectively assist the driver in tracking the target path under lateral wind interference and driver misoperation,and the TD3-based coordination control strategy has better overall performance. 展开更多
关键词 Path tracking Human-machine co-driving Parallel steering coordination Deep reinforcement learning
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Endo-atmospheric maneuver penetration strategy based on generative adversarial reinforcement learning
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作者 Yaoluo HUI Xiumin LI +2 位作者 Chen LIANG Junzheng SUN Zheng DU 《Chinese Journal of Aeronautics》 2025年第4期394-407,共14页
An intelligent endo-atmospheric penetration strategy based on generative adversarialreinforcement learning is proposed in this manuscript.Firstly,attack and defense adversarial mod-els are established,and missile mane... An intelligent endo-atmospheric penetration strategy based on generative adversarialreinforcement learning is proposed in this manuscript.Firstly,attack and defense adversarial mod-els are established,and missile maneuver penetration problem is transformed into an optimal con-trol problem,considering penetration,handover position and mid-terminal guidance velocityconstraints.Then,Radau Pseudospectral method is adopted to generate data samples consideringrandom perturbations.Furthermore,Generative Adversarial Imitation Learning Combined withDeep Deterministic Policy Gradient method(GAIL-DDPG)is designed,with internal processreward signals constructed to tackle long-term sparse reward in missile manuver penetration prob-lem.Finally,penetration strategy is trained and verified.Simulation shows that using generativeadversarial reinforcement learning,with sample library to learn expert experience in training earlystage,the proposed method can quickly converge.Also,performance is further optimized with rein-forcement learning exploration strategy in the later stage of training.Simulation shows that the pro-posed method has better engineering application ability compared with traditional reinforcementlearning method. 展开更多
关键词 Hypersonic glide vehicle Endo-atmospheric penetration strategy Deep reinforcement learning GUIDANCE GAIL-DDPG
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Personalized Aggregation Strategy for Hierarchical Federated Learning in Internet of Vehicles
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作者 Shi Yan Liu Yujia +1 位作者 Tong Xiaolu Zhou Shukui 《China Communications》 2025年第8期314-331,共18页
In Internet of Vehicles,VehicleInfrastructure-Cloud cooperation supports diverse intelligent driving and intelligent transportation applications.Federated Learning(FL)is the emerging computation paradigm to provide ef... In Internet of Vehicles,VehicleInfrastructure-Cloud cooperation supports diverse intelligent driving and intelligent transportation applications.Federated Learning(FL)is the emerging computation paradigm to provide efficient and privacypreserving collaborative learning.However,in Io V environment,federated learning faces the challenges introduced by high mobility of vehicles and nonIndependently Identically Distribution(non-IID)of data.High mobility causes FL clients quit and the communication offline.The non-IID data leads to slow and unstable convergence of global model and single global model's weak adaptability to clients with different localization characteristics.Accordingly,this paper proposes a personalized aggregation strategy for hierarchical Federated Learning in Io V environment,including Fed SA(Special Asynchronous Federated Learning with Self-adaptive Aggregation)for low-level FL between a Road Side Unit(RSU)and the vehicles within its coverage,and Fed Att(Federated Learning with Attention Mechanism)for high-level FL between a cloud server and multiple RSUs.Agents self-adaptively obtain model aggregation weight based on Advantage Actor-Critic(A2C)algorithm.Experiments show the proposed strategy encourages vehicles to participate in global aggregation,and outperforms existing methods in training performance. 展开更多
关键词 aggregation strategy Internet of Vehicles non-IID personalized federated learning vehicle mobility
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Parameterized evasion strategy for hypersonic glide vehicles against two missiles based on reinforcement learning
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作者 Zeming HAO Ran ZHANG Huifeng LI 《Chinese Journal of Aeronautics》 2025年第4期450-468,共19页
In practical combat scenarios,Hypersonic Glide Vehicles(HGV)face the challenge of evading Successive Pursuers from the Same Direction while satisfying the Homing Constraint(SPSDHC).To address this problem,this paper p... In practical combat scenarios,Hypersonic Glide Vehicles(HGV)face the challenge of evading Successive Pursuers from the Same Direction while satisfying the Homing Constraint(SPSDHC).To address this problem,this paper proposes a parameterized evasion guidance algorithm based on reinforcement learning.The three-player optimal evasion strategy is firstly analyzed and approximated by parametrization.The switching acceleration command of HGV optimal evasion strategy considering the upper limit of missile acceleration command is analyzed based on the optimal control theory.The terminal miss of HGV in the case of evading two missiles is analyzed,which means that the three-player optimal evasion strategy is a linear combination of two one-toone strategies.Then,a velocity control algorithm is proposed to increase the terminal miss by actively controlling the flight speed of the HGV based on the parametrized evasion strategy.The reinforcement learning method is used to implement the strategy in real time and a reward function is designed by deducing homing strategy for the HGV to approach the target,which ensures that the HGV satisfies the homing constraint.Experimental results demonstrate the feasibility and robustness of the proposed parameterized evasion strategy,which enables the HGV to generate maximum terminal miss and satisfy homing constraint when facing single or double missiles. 展开更多
关键词 Hypersonic glide vehicle Optimal control theory Evasion strategy Three players Reinforcement learning
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Optimization of Robotic Arm Grasping Strategy Based on Deep Reinforcement Learning
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作者 Dongjun He 《计算机科学与技术汇刊(中英文版)》 2025年第2期1-7,共7页
In recent years,robotic arm grasping has become a pivotal task in the field of robotics,with applications spanning from industrial automation to healthcare.The optimization of grasping strategies plays a crucial role ... In recent years,robotic arm grasping has become a pivotal task in the field of robotics,with applications spanning from industrial automation to healthcare.The optimization of grasping strategies plays a crucial role in enhancing the effectiveness,efficiency,and reliability of robotic systems.This paper presents a novel approach to optimizing robotic arm grasping strategies based on deep reinforcement learning(DRL).Through the utilization of advanced DRL algorithms,such as Q-Learning,Deep Q-Networks(DQN),Policy Gradient Methods,and Proximal Policy Optimization(PPO),the study aims to improve the performance of robotic arms in grasping objects with varying shapes,sizes,and environmental conditions.The paper provides a detailed analysis of the various deep reinforcement learning methods used for grasping strategy optimization,emphasizing the strengths and weaknesses of each algorithm.It also presents a comprehensive framework for training the DRL models,including simulation environment setup,the optimization process,and the evaluation metrics for grasping success.The results demonstrate that the proposed approach significantly enhances the accuracy and stability of the robotic arm in performing grasping tasks.The study further explores the challenges in training deep reinforcement learning models for real-time robotic applications and offers solutions for improving the efficiency and reliability of grasping strategies. 展开更多
关键词 Robotic Arm Grasping strategy Deep Reinforcement learning Q-learning DQN Policy Gradient PPO OPTIMIZATION Simulation Robotics
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Machine learning-based investigation of uplift resistance in special-shaped shield tunnels using numerical finite element modeling 被引量:1
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作者 ZHANG Wengang YE Wenyu +2 位作者 SUN Weixin LIU Zhicheng LI Zhengchuan 《土木与环境工程学报(中英文)》 北大核心 2026年第1期1-13,共13页
The uplift resistance of the soil overlying shield tunnels significantly impacts their anti-floating stability.However,research on uplift resistance concerning special-shaped shield tunnels is limited.This study combi... The uplift resistance of the soil overlying shield tunnels significantly impacts their anti-floating stability.However,research on uplift resistance concerning special-shaped shield tunnels is limited.This study combines numerical simulation with machine learning techniques to explore this issue.It presents a summary of special-shaped tunnel geometries and introduces a shape coefficient.Through the finite element software,Plaxis3D,the study simulates six key parameters—shape coefficient,burial depth ratio,tunnel’s longest horizontal length,internal friction angle,cohesion,and soil submerged bulk density—that impact uplift resistance across different conditions.Employing XGBoost and ANN methods,the feature importance of each parameter was analyzed based on the numerical simulation results.The findings demonstrate that a tunnel shape more closely resembling a circle leads to reduced uplift resistance in the overlying soil,whereas other parameters exhibit the contrary effects.Furthermore,the study reveals a diminishing trend in the feature importance of buried depth ratio,internal friction angle,tunnel longest horizontal length,cohesion,soil submerged bulk density,and shape coefficient in influencing uplift resistance. 展开更多
关键词 special-shaped tunnel shield tunnel uplift resistance numerical simulation machine learning
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Investigation and Strategy Research on the Causes of Middle School Students’Learning Difficulties in the Context of the Leading Country in Education
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作者 Jun-Jie Yan Xiao-Nan Luo +2 位作者 Qun-Fang Zeng Hui-Lin Zhang Jian-Nan Wu 《教育技术与创新》 2025年第2期1-10,共10页
The purpose of this research is to analyze the causal mechanisms of learning difficulties of middle school students and use them to propose strategies to help them.This research is particularly valuable for its focus ... The purpose of this research is to analyze the causal mechanisms of learning difficulties of middle school students and use them to propose strategies to help them.This research is particularly valuable for its focus on middle school students.Research on this critical transition period is often lacking compared to primary and high school.Therefore,this research establishes a structured equation model and analyzes the data from the survey using the partial least squares method.The data were obtained from a 13,900 Wenzhou City,China students’questionnaire.The research found that learning strategies were the most significant influences on learning effectiveness,followed by learning motivation and learning relationships.Meanwhile,learning relationships had a significant impact on learning pressure.Therefore,this research proposes targeted support strategies.It aims to enhance learning motivation(Set achievable learning goals for each student with learning difficulties based on their actual situation),optimize learning strategies(Encourage students with learning difficulties to learn self-regulatory strategies such as goal setting,time management,and self-reflection),and improve learning relationships(Establish a good social network to promote positive interaction between students with learning difficulties and their peers).At the same time,it reduces students’learning pressure.Ultimately,the learning effectiveness of students with learning difficulties is improved. 展开更多
关键词 support strategies leading country in education students with learning difficulties middle school students
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Unpacking the Role of Grammarly in Iterative Continuation Tasks to Develop L2 Grammar Learning Strategies,Grit,and Competence
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作者 Jianling Zhan Chuyi Zhou 《Chinese Journal of Applied Linguistics》 2026年第1期112-132,161,共22页
The iterative continuation task(ICT)requires English as a foreign language(EFL)learners to read a segment and write a continuation that aligns with the preceding segment of an English novel with successive turns,offer... The iterative continuation task(ICT)requires English as a foreign language(EFL)learners to read a segment and write a continuation that aligns with the preceding segment of an English novel with successive turns,offering exposure to diverse grammatical structures and opportunities for contextualized usage.Given the importance of integrating technology into second language(L2)writing and the critical role that grammar plays in L2 writing development,automated written corrective feedback provided by Grammarly has gained significant attention.This study investigates the impact of Grammarly on grammar learning strategies,grammar grit,and grammar competence among EFL college students engaged in ICT.This study employed a mixed-methods sequential exploratory design;56 participants were divided into an experimental group(n=28),receiving Grammarly feedback for ICT,and a control group(n=28),completing ICT without Grammarly feedback.Quantitative results revealed that both groups showed improvements in L2 grammar learning strategies,grit and competence.For the experimental group,significant differences were observed across all variables of L2 grammar learning strategies,grit,and competence between pre-and post-tests.For the control group,significant differences were only observed in the affective dimension of grammar learning strategies,Consistency of Interest(COI)of grammar grit,and grammar competence.However,the control group presented a significantly higher improvement in grammar competence.Qualitative analysis showed both positive and negative perceptions of Grammarly.The pedagogical implications of integrating Grammarly and ICT for L2 grammar development are discussed. 展开更多
关键词 grammar learning strategies grammar grit grammar competence iterative continuation tasks Grammarly
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Machine learning-based design strategy for weak vibration pipes conveying fluid
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作者 Tianchang DENG Hu DING +1 位作者 SKITIPORNCHAI Jie YANG 《Applied Mathematics and Mechanics(English Edition)》 2025年第7期1215-1236,共22页
Multi-constrained pipes conveying fluid,such as aircraft hydraulic control pipes,are susceptible to resonance fatigue in harsh vibration environments,which may lead to system failure and even catastrophic accidents.In... Multi-constrained pipes conveying fluid,such as aircraft hydraulic control pipes,are susceptible to resonance fatigue in harsh vibration environments,which may lead to system failure and even catastrophic accidents.In this study,a machine learning(ML)-assisted weak vibration design method under harsh environmental excitations is proposed.The dynamic model of a typical pipe is developed using the absolute nodal coordinate formulation(ANCF)to determine its vibrational characteristics.With the harsh vibration environments as the preserved frequency band(PFB),the safety design is defined by comparing the natural frequency with the PFB.By analyzing the safety design of pipes with different constraint parameters,the dataset of the absolute safety length and the absolute resonance length of the pipe is obtained.This dataset is then utilized to develop genetic programming(GP)algorithm-based ML models capable of producing explicit mathematical expressions of the pipe's absolute safety length and absolute resonance length with the location,stiffness,and total number of retaining clips as design variables.The proposed ML models effectively bridge the dataset with the prediction results.Thus,the ML model is utilized to stagger the natural frequency,and the PFB is utilized to achieve the weak vibration design.The findings of the present study provide valuable insights into the practical application of weak vibration design. 展开更多
关键词 pipe conveying fluid machine learning(ML) pipe design strategy RESONANCE genetic programming(GP) inverse design preserved frequency band(PFB)
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Quantifying Global Black Carbon Aging Responses to Emission Reductions Using a Machine Learning-based Climate Model 被引量:1
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作者 Wenxiang SHEN Minghuai WANG +5 位作者 Junchang WANG Yawen LIU Xinyi DONG Xinyue SHAO Man YUE Yaman LIU 《Advances in Atmospheric Sciences》 2026年第2期361-372,I0004-I0009,共18页
Countries around the world have been making efforts to reduce pollutant emissions. However, the response of global black carbon(BC) aging to emission changes remains unclear. Using the Community Atmosphere Model versi... Countries around the world have been making efforts to reduce pollutant emissions. However, the response of global black carbon(BC) aging to emission changes remains unclear. Using the Community Atmosphere Model version 6 with a machine-learning-integrated four-mode version of the Modal Aerosol Module, we quantify global BC aging responses to emission reductions for 2011–2018 and for 2050 and 2100 under carbon neutrality. During 2011–18, global trends in BC aging degree(mass ratio of coatings to BC, R_(BC)) exhibited marked regional disparities, with a significant increase in China(5.4% yr^(-1)), which contrasts with minimal changes in the USA, Europe, and India. The divergence is attributed to opposing trends in secondary organic aerosol(SOA) and sulfate coatings, driven by regional changes in the emission ratios of corresponding coating precursors to BC(volatile organic compounds-VOCs/BC and SO_(2)/BC). Projections under carbon neutrality reveal that R_(BC) will increase globally by 47%(118%) in 2050(2100), with strong convergent increases expected across major source regions. The R_(BC) increase, primarily driven by enhanced SOA coatings due to sharper BC reductions relative to VOCs, will enhance the global BC mass absorption cross-section(MAC) by 11%(17%) in 2050(2100).Consequently, although the global BC burden will decline sharply by 60%(76%), the enhanced MAC partially offsets the magnitude of the decline in the BC direct radiative effect, resulting in the moderation of global BC DRE decreases to 88%(92%) of the BC burden reductions in 2050(2100). This study highlights the globally enhanced BC aging and light absorption capacity under carbon neutrality, thereby partly offsetting the impact of BC direct emission reductions on future changes in BC radiative effects globally. 展开更多
关键词 black carbon aging trend emission reduction carbon neutrality machine learning
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PowerVLM:基于Federated Learning与模型剪枝的电力视觉语言大模型
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作者 欧阳旭东 雒鹏鑫 +3 位作者 何绍洋 崔艺林 张中超 闫云凤 《全球能源互联网》 北大核心 2026年第1期101-111,共11页
智能电网的快速发展衍生出多模态、多源异构的海量电力数据,给人工智能模型在复杂电力场景感知带来了挑战,同时行业数据的敏感性和隐私保护需求进一步限制了通用模型在电力领域的跨场景迁移能力。对此,提出了一种基于Federated Learnin... 智能电网的快速发展衍生出多模态、多源异构的海量电力数据,给人工智能模型在复杂电力场景感知带来了挑战,同时行业数据的敏感性和隐私保护需求进一步限制了通用模型在电力领域的跨场景迁移能力。对此,提出了一种基于Federated Learning与模型剪枝的电力视觉语言大模型。提出了一种基于类别引导的电力视觉语言大模型PowerVLM,设计了类别引导增强模块,增强模型对电力图文数据的理解和问答能力;采用FL的强化学习训练策略,在满足数据隐私保护下,降低域间差异对模型性能的影响;最后,提出了一种基于信息决议的模型剪枝算法,可实现低训练参数的模型高效微调。分别在变电巡检、输电任务、作业安监3种典型电力场景开展实验,结果表明,该方法在电力场景多模态问答任务中的METEOR、BLEU和CIDEr等各项指标均表现优异,为电力场景智能感知提供了新的技术思路和方法支撑。 展开更多
关键词 智能电网 人工智能 视觉语言大模型 Federated learning 模型剪枝
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A Systematic Review of Anxiety, Motivation, and Strategy in Learning Chinese as a Second Language From 2008 to 2022
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作者 Xinya Lan 《Chinese Journal of Applied Linguistics》 2025年第3期325-351,480,共28页
Anxiety,motivation,and strategy have long been seen as critical in second language acquisition.This study presents a systematic review of the literature on these variables in terms of their relationship with one anoth... Anxiety,motivation,and strategy have long been seen as critical in second language acquisition.This study presents a systematic review of the literature on these variables in terms of their relationship with one another,their effects on learning outcomes,and how they are affected by technology-assisted tools in the teaching of Chinese as a second language.This study includes 24 articles for the review study based on the criteria and process of the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocol(PRISMA-P)and the clustering techniques of VOSviewer.It is found that 1)anxiety,motivation,and strategy were interrelated,that is,motivation was negatively associated with anxiety but positively related to strategy,while strategy could positively predict anxiety;2)anxiety could both positively and negatively affect learning outcomes,while motivation and strategy could both positively and insignificantly influence learning outcomes;3)the technology-assisted tools used in the classroom could both positively and negatively affect the levels of these variables and learning outcomes in the L2 Chinese context.The need to explore more complicated relationships between language-specific individual variables themselves and other possible factors that affect these variables,such as cultural ones,are also discussed for future research. 展开更多
关键词 ANXIETY MOTIVATION strategy technology-assisted tools Chinese as a second language
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A DDPG-based Path Following Control Strategy for Autonomous Vehicles by Integrated Imitation Learning and Feedforward Exploration
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作者 Qianjie Liu Peixiang Xiong +4 位作者 Qingyuan Zhu Wei Xiao Kejie Wang Guoliang Hu Gang Li 《Chinese Journal of Mechanical Engineering》 2025年第5期207-223,共17页
Autonomous driving technology is constantly developing to a higher level of complex scenes,and there is a growing demand for the utilization of end-to-end data-driven control.However,the end-to-end path tracking proce... Autonomous driving technology is constantly developing to a higher level of complex scenes,and there is a growing demand for the utilization of end-to-end data-driven control.However,the end-to-end path tracking process often encounters challenges in learning efficiency and generalization.To address this issue,this paper designs a deep deterministic policy gradient(DDPG)-based reinforcement learning strategy that integrates imitation learning and feedforward exploration in the path following process.In imitation learning,the path tracking control data generated by the model predictive control(MPC)method is used to train an end-to-end steering control model of a deep neural network.Another feedforward exploration behavior is predicted by road curvature and vehicle speed,and adds it and imitation learning to the DDPG reinforcement learning to obtain decision-making experience and action prediction behavior of the path tracking process.In the reinforcement learning process,imitation learning is used to update the pre-training parameters of the actor network,and a feedforward steering technique with random noise is adopted for strategy exploration.In the reward function,a hierarchical progressive reward form and a constrained objective reward function referring to MPC are designed,and the actor-critic network architecture is determined.Finally,the path tracking performance of the designed method is verified by comparing various training results,simulations,and HIL tests.The results show that the designed method can effectively utilize pre-training and feedforward prior experience to obtain optimal path tracking performance of an autonomous vehicle,and has better generalization ability than other methods.This study provides an efficient control scheme for improving the end-to-end control performance of autonomous vehicles. 展开更多
关键词 Autonomous vehicle Path following Feedforward exploration Reinforcement learning
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CASBA:Capability-Adaptive Shadow Backdoor Attack against Federated Learning
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作者 Hongwei Wu Guojian Li +2 位作者 Hanyun Zhang Zi Ye Chao Ma 《Computers, Materials & Continua》 2026年第3期1139-1163,共25页
Federated Learning(FL)protects data privacy through a distributed training mechanism,yet its decentralized nature also introduces new security vulnerabilities.Backdoor attacks inject malicious triggers into the global... Federated Learning(FL)protects data privacy through a distributed training mechanism,yet its decentralized nature also introduces new security vulnerabilities.Backdoor attacks inject malicious triggers into the global model through compromised updates,posing significant threats to model integrity and becoming a key focus in FL security.Existing backdoor attack methods typically embed triggers directly into original images and consider only data heterogeneity,resulting in limited stealth and adaptability.To address the heterogeneity of malicious client devices,this paper proposes a novel backdoor attack method named Capability-Adaptive Shadow Backdoor Attack(CASBA).By incorporating measurements of clients’computational and communication capabilities,CASBA employs a dynamic hierarchical attack strategy that adaptively aligns attack intensity with available resources.Furthermore,an improved deep convolutional generative adversarial network(DCGAN)is integrated into the attack pipeline to embed triggers without modifying original data,significantly enhancing stealthiness.Comparative experiments with Shadow Backdoor Attack(SBA)across multiple scenarios demonstrate that CASBA dynamically adjusts resource consumption based on device capabilities,reducing average memory usage per iteration by 5.8%.CASBA improves resource efficiency while keeping the drop in attack success rate within 3%.Additionally,the effectiveness of CASBA against three robust FL algorithms is also validated. 展开更多
关键词 Federated learning backdoor attack generative adversarial network adaptive attack strategy distributed machine learning
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Dual-strategy approach for fungicide discovery: Machine learning-based activity prediction and fragment co-occurrence network construction
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作者 Binyan Jin Jialin Cui +4 位作者 Qi He Huan Xu Xinpeng Sun Ziyao Chai Li Zhang 《Advanced Agrochem》 2025年第4期373-381,共9页
The development of fungicides is time-consuming and costly.Introducing a fungicide-likeness assessment strategy at the early screening stage can help reduce development risks and improve the success rate.However,exist... The development of fungicides is time-consuming and costly.Introducing a fungicide-likeness assessment strategy at the early screening stage can help reduce development risks and improve the success rate.However,existing assessment methods are often plagued by low accuracy and poor generalization,while fragment-based design strategies commonly fail to account for synergistic effects between structural units.Therefore,based on a small-scale sample set,this study developed a more efficient global predictive model for fungicidal activity—-named APPf—by integrating multi-scale feature screening methods and machine learning algorithms,which also accounts for synergistic effects among different structural fragments.We utilized three independent external test sets for model validation:External Test Set 1 for general validation,External Test Set 2 for comparison with existing models,and External Test Set 3 for disease-specific fungicide evaluation.On External Test Set 1,the APPf model achieved a precision of 0.6454,a recall of 0.8535,and an F1 score of 0.7350,demonstrating its robust predictive performance.It also exhibited strong enrichment capability for positive samples in External Test Set 2.For External Test Set 3,APPf achieved a prediction accuracy exceeding 80%for each disease,suggesting its promising potential in practical fungicide development.Furthermore,we quantified the contribution of molecular descriptors to the model predictions using SHAP value analysis and identified nHdNH and NssssNp as strong indicative features for predicting fungicidal activity,thereby enhancing the interpretability of the model.APPf has been deployed on a public web server(http://pesticides.cau.edu.cn/APPf),providing a user-friendly online prediction service to support the discovery of novel fungicides.Meanwhile,we employed a molecular fragmentation strategy to analyze the co-occurrence relationships between fragments in fungicides and constructed a network map of fragment co-occurrence associated with fungicidal activity.This study provides both an active fragment library and a global fungicide-likeness assessment tool for AI-based de novo molecular generation aimed at discovering novel fungicidal leads,which is expected to enhance the efficiency of developing new fungicides. 展开更多
关键词 Machine learning Activity prediction Fragment co-occurrence Interpretability Online website
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Achieving High Power Density in Paper-based Piezoelectric Nanogenerators through Dual-phase BCZT Doping Strategy
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作者 WANG Siting SUN Zixiong +3 位作者 LIU Xinyingl HAN Peiqiao WANG Xiuli ZHANG Sufeng 《无机材料学报》 北大核心 2026年第1期129-140,共12页
Development of high performance,flexible piezoelectric nanogenerators(PENGs)is critical for advancing self-powered sensing and microelectronic applications.In this study,a hydrogen-bond substitute strategy was employe... Development of high performance,flexible piezoelectric nanogenerators(PENGs)is critical for advancing self-powered sensing and microelectronic applications.In this study,a hydrogen-bond substitute strategy was employed to fabricate a multi-layer PENG based on a cellulose/polyvinylidene fluoride(PVDF)blend film matrix,incorporating multi-phase BCZT(0.1BaZr_(0.2)Ti_(0.8)O_(3)-0.9Ba_(0.7)Ca_(0.3)TiO_(3))ceramic fillers.Structural characterization via SEM and TEM revealed that an intricate hydrogen-bond network facilitated the uniform dispersion of ceramic fillers within the composite film’s sub-layers.In order to study the effect of filler distribution on piezoelectric performance,the single-and double-layer composite films with varying BCZT configurations were produced and evaluated.The results demonstrated that double-layer PENGs exhibit significantly enhanced electrical output compared to their single-layer counterparts,with the D-L_(3)H_(7) configuration achieving an open circuit voltage(V_(OC))of 23.13 V and a short circuit current(I_(SC))of 8.32μA.This enhancement is attributed to increased inter-layer interfaces,which effectively suppressed charge injection and migration,leading to improved charge density.Additionally,the presence of sharp tipped hexagonal tetragonal phase nanoparticles induced an electric field enhancement effect,further optimizing performance. 展开更多
关键词 piezoelectric nanogenerator cellulose BCZT hydrogen bond engineering strategy
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A deep learning strategy for accurate identification of purebred and hybrid pigs across SNP chips
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作者 Zipeng Zhang Zhengwen Fang +6 位作者 Yongwang Du Yilin He Changsong Qian Weijian Ye Ning Zhang Jianan Zhang Xiangdong Ding 《Journal of Animal Science and Biotechnology》 2025年第6期2592-2604,共13页
Background Breed identification plays an important role in conserving indigenous breeds,managing genetic resources,and developing effective breeding strategies.However,researches on breed identification in livestock m... Background Breed identification plays an important role in conserving indigenous breeds,managing genetic resources,and developing effective breeding strategies.However,researches on breed identification in livestock mainly focused on purebreds,and they yielded lower predict accuracy in hybrid.In this study,we presented a Multi-Layer Perceptron(MLP)model with multi-output regression framework specifically designed for genomic breed composition prediction of purebred and hybrid in pigs.Results We utilized a total of 8,199 pigs from breeding farms in eight provinces in China,comprising Yorkshire,Landrace,Duroc and hybrids of Yorkshire×Landrace.All the animals were genotyped with 1K,50K and 100K SNP chips.Comparing with random forest(RF),support vector regression(SVR)and Admixture,our results from five replicates of fivefold cross validation demonstrated that MLP achieved a breed identification accuracy of 100%for both hybrid and purebreds in 50K and 100K SNP chips,SVR performed comparable with MLP,they both outperformed RF and Admixture.In the independent testing,MLP yielded accuracy of 100%for all three pure breeds and hybrid across all SNP chips and panel,while SVR yielded 0.026%–0.121%lower accuracy than MLP.Compared with classification-based framework,the new strategy of multi-output regression framework in this study was helpful to improve the predict accuracy.MLP,RF and SVR,achieved consistent improvements across all six SNP chips/panel,especially in hybrid identification.Our results showed the determination threshold for purebred had different effects,SVR,RF and Admixture were very sensitive to threshold values,their optimal threshold fluctuated in different scenarios,while MLP kept optimal threshold 0.75 in all cases.The threshold of 0.65–0.75 is ideal for accurate breed identification.Among different density of SNP chips,the 1K SNP chip was most cost-effective as yielding 100%accuracy with enlarging training set.Hybrid individuals in the training set were useful for both purebred and hybrid identification.Conclusions Our new MLP strategy demonstrated its high accuracy and robust applicability across low-,medium-,and high-density SNP chips.Multi-output regression framework could universally enhance prediction accuracy for ML methods.Our new strategy is also helpful for breed identification in other livestock. 展开更多
关键词 Breed identification Genomic breed composition HYBRID Machine learning Multi-output regression
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