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Distributed optimal consensus control for multiagent systems based on event-triggered and prioritized experience replay strategies

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Science China(Information Sciences) 2025年第1期68卷 306-321页

作者： Cuijuan ZHANG Lianghao JI Shasha YANG Xing guo Huaqing LI Chongqing Key Laboratory of Image Cognition Chongqing University of Posts and Telecommunications Key Laboratory of Intelligent Perception and Computing of Anhui Province Anqing Normal University College of Electronic and Information Engineering Southwest University

This study uses event-triggered(ET) and reinforcement learning methods to investigate the optimal consensus control problem for cooperative-competitive multiagent systems. It proposes a novel distributed ET control strategy, which relies on a prioritized experience replay(PER) policy. This strategy not only conserves communication resources but also ensures acceptable system performance. To implement the proposed method, actor-critic(AC) dual-structured neural networks(NNs) are used to approximate the value function and control policy. In the AC NNs, the weight estimates for the NNs are updated at the moment of event triggering, resulting in a nonperiodic weight adjustment pattern. This approach decreases the computational cost in comparison with the traditional ET mechanism. The PER-based ET mechanism makes full use of valid historical data and effectively establishes a balance between system performance and communication resource ***, it does not require the following two conditions in most existing studies:(1) requirement of the system dynamics model to be known, and(2) persistent excitation. In addition, Zeno behavior is excluded from this study. Finally, a simulation is conducted to confirm the validity of the suggested approach.

关键词： multiagent systems event-triggered mechanism prioritized experience replay dual-structured neural networks optimal consensus control

Enantioselective reductive conjugate alkenylation of α,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第1期68卷 157-162页

作者： Rong-De he Yun-Lei Luo Qiu-Quan Pan Qi-Wei Yao Xing-Zhong Shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis, yet their asymmetric variant remains elusive. Concurrently, asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–M. This manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl acetates. The method facilitates the enantioselective addition of keto alkenyl groups to α,β-enones, resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access otherwise. The use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

The effects of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents:a meta-analysis

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Neural Regeneration Research 2025年第5期20卷 1513-1520页

作者： Xueyun Shao Longfei he Yangyang Liu Physical Education School Shenzhen UniversityShenzhenGuangdong ProvinceChina Shenzhen Institute of Neuroscience ShenzhenGuangdong ProvinceChina

Brain-derived neurotrophic factor is a crucial neurotrophic factor that plays a significant role in brain health. Although the vast majority of meta-analyses have confirmed that exercise interventions can increase brain-derived neurotrophic factor levels in children and adolescents, the effects of specific types of exercise on brain-derived neurotrophic factor levels are still controversial. To address this issue, we used meta-analytic methods to quantitatively evaluate, analyze, and integrate relevant studies. Our goals were to formulate general conclusions regarding the use of exercise interventions, explore the physiological mechanisms by which exercise improves brain health and cognitive ability in children and adolescents, and provide a reliable foundation for follow-up research. We used the Pub Med, Web of Science, Science Direct, Springer, Wiley Online Library, Weipu, Wanfang, and China National Knowledge Infrastructure databases to search for randomized controlled trials examining the influences of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents. The extracted data were analyzed using Review Manager 5.3. According to the inclusion criteria, we assessed randomized controlled trials in which the samples were mainly children and adolescents, and the outcome indicators were measured before and after the intervention. We excluded animal experiments, studies that lacked a control group, and those that did not report quantitative results. The mean difference(MD;before versus after intervention) was used to evaluate the effect of exercise on brain-derived neurotrophic factor levels in children and adolescents. Overall, 531 participants(60 children and 471 adolescents, 10.9–16.1 years) were included from 13 randomized controlled trials. heterogeneity was evaluated using the Q statistic and I^(2) test provided by Review Manager software. The meta-analysis showed that there was no heterogeneity among the studies(P = 0.67,

关键词： adolescents brain-derived neurotrophic factor children exercise meta-analysis randomized controlled trials

Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期7卷 152-160页

作者： Zhi-Jun Xie Jia-Lin Li Ling Gong xiang-Li Zhong Hong-Jia Song Jin-Bin Wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance

Morphological Mechanism and Experimental Verification of Self-healing of Basalt-fiber Modified Water-soaked Asphalt

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 171-186页

作者： XIAO Minmin DONG Jinyong LI Chunyan guo Xu REN Jianguo School of Urban Construction and Safety Engineering Shanghai Institute of TechnologyShanghai 201418China

This study investigates the mechanism of action of representative molecules of basalt fibers on the healing of water-soaked *** parameters,morphological characteristics,interfacial healing energy,and interfacial healing strength were analyzed using molecular dynamics and macroscopic tests under different time,temperature,and water conditions to evaluate the specific states and critical conditions involved in *** results indicate that basalt-fiber molecules can induce rearrangement and a combination of water-soaked asphalt at the healing *** groups with different bonding states increase the interfacial adsorption capacity of water-soaked *** interaction between basalt fiber molecules and water molecules leads to a"hoop"phenomenon,while aromatics-2 molecules exhibit a"ring band aggregation"*** former reduces the miscibility of water and asphalt molecules,while the latter causes slow diffusion of the ***,a micro-macro dual-scale comparison of interfacial healing strength was conducted at temperatures of 297.15 and 312.15 K to identify the strength transition point and critical temperature of 299.4 K during the self-healing process of basalt-fiber modified water-soaked asphalt.

关键词： water-soaked asphalt basalt-fibers self-healing properties moisture status molecular characterization

Mn-Fe普鲁士蓝类似物制备费托合成催化剂及其性能研究

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现代化工 2022年第2期42卷 204-209页

作者：郭祥贺刘广波李冰爽杨胜男李琢于建强青岛大学化学化工学院山东青岛266000 中国科学院青岛生物能源与过程研究所山东青岛266000

锰是铁基费托合成催化剂的常用助剂,其引入方式是影响催化剂性能的重要因素。以Mn-Fe普鲁士蓝类似物为前驱体,经简单焙烧制备了核壳型Mn-FeC_(x)@C催化剂,通过考察助剂锰质量分数对催化剂结构性质及催化性能的影响,研究锰质量分数对催... 详细信息

锰是铁基费托合成催化剂的常用助剂,其引入方式是影响催化剂性能的重要因素。以Mn-Fe普鲁士蓝类似物为前驱体,经简单焙烧制备了核壳型Mn-FeC_(x)@C催化剂,通过考察助剂锰质量分数对催化剂结构性质及催化性能的影响,研究锰质量分数对催化剂结构变化规律和催化剂构效关系的影响。结果表明,锰的引入改变了催化剂FeC_(x)活性相的生成和表面性质,并在一定程度上降低了催化剂活性,增加了产物低碳烃的烯烷比,当锰质量分数为2%时,低碳产物烯烷比可达4.8。锰的引入对催化剂FeC_(x)活性相结构的影响是引起反应性能变化的主要原因。

关键词：费托合成铁碳化合物普鲁士蓝类似物低碳烯烃烯烷比

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Personalized federated few-shot node classification

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Science China(Information Sciences) 2025年第1期68卷 204-218页

作者： Yunfeng ZHAO Xintong he guoxian YU Jun WANG Yongqing ZheNG Carlotta DOMENICONI School of Software Shandong University Joint SDU-NTU Centre for Artificial Intelligence Research Shandong University Department of Mathematics National University of Singapore Department of Computer Science George Mason University

Personalized federated learning(PFL) aims to train customized models for individual clients in a decentralized setting, with the account of non-independent and identically distributed data across clients. However, most PFL methods adopt uniform classification layers for diverse clients and give rise to error-prone predictions, due to the task heterogeneity notably prominent in decentralized graph data scenarios. Although some PFL solutions setup client-specific classification layers for each client and optimize them only locally, they are corrupted with limited local training data. We propose an innovative solution called federated parameter decoupling and node augmentation(Fed PANo) to address these problems and to achieve personalized federated few-shot node classification, which is a prevalent and challenging but unexplored topic. Specifically, Fed PANo first separates the local model into the GNN and classifier to handle unique client-specific task variations. The GNN is trained through federated learning to capture shared knowledge of graph nodes across clients, while the classifier is custom-designed and trained individually for each client. Additionally, a generic classifier shared among clients is adopted to encourage the GNN's grasp of shared information. Then Fed PANo further proposes the node generator along with its local and collaborative training strategies to deal with the node scarcity of clients. Extensive experimental results on benchmark datasets confirm that Fed PANo outperforms eight competitive baselines across different settings.

关键词： personalized federated learning few-shot learning node classification task heterogeneity parameter decoupling node augmentation

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柔性微服务监控框架

计算机系统应用 2017年第10期26卷 139-143页

作者：刘一田刘士进郭伟何翔南瑞集团公司(国网电力科学研究院) 南京210003

微服务细化了服务的粒度,针对微服务的监控是微服务管理需要面对的核心问题,以可扩展全链路应用服务监控为目标,在已有服务管理层之上设计实现了一种柔性微服务监控框架,用于监控微服务状态和不断变化的服务负载,与已有的分布式监控架... 详细信息

微服务细化了服务的粒度,针对微服务的监控是微服务管理需要面对的核心问题,以可扩展全链路应用服务监控为目标,在已有服务管理层之上设计实现了一种柔性微服务监控框架,用于监控微服务状态和不断变化的服务负载,与已有的分布式监控架构相比,这种监控框架灵活度更高,对服务变化的感知能力更强,使用Raft算法增强了数据一致性,避免了单点故障的情况,经试验分析,代价更小,在实际项目中验证了框架及方法的有效性.

关键词：柔性微服务监控智能分析告警

Catalytic Performance of Carbon Smoke over Ag-LSCF Composite Catalysts

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 30-34页

作者： guo Guanlun HAN Ming LU Shaomin YU Jing JU Hongling 无 Hubei Key Laboratory of Advanced Technology for Automotive Components&Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of TechnologyWuhan 430070China College of Mechanical and Transportation Southwest Forestry UniversityKunming 650000China

To improve the catalytic performance of La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3)(LSCF)towards carbon soot,we utilized the impregnation method to incorporate Ag into the prepared LSCF *** conducted a series of characterization tests and evaluated the soot catalytic activity of the composite catalyst by comparing it with the LaCoO_(3) group,LaFeO_(3) group,and catalyst-free *** results indicate that the Ag-LSCF composite catalyst exhibits the highest soot catalytic activity,with the characteristic temperature values of 376.3,431.1,and 473.9℃at 10%,50%,and 90%carbon soot conversion,*** values are 24.8,20.2,and 23.1℃lower than those of the LSCF *** also shows that LSCF can improve the catalytic activity of soot after compounding with Ag,and reflects the necessity of using catalysts in soot combustion *** characterization and BET test show that Ag-LSCF has more abundant surface-adsorbed oxygen species,larger specific surface area and pore volume than LSCF,which also proves that Ag-LSCF has higher soot catalytic activity.

关键词： metallic composites carbon smoke oxidation perovskite catalyst soot