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Learning discrete adaptive receptive fields for graph convolutional networks

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Science China(Information Sciences) 2023年第12期66卷 5-15页

作者： Xiaojun MA Ziyao LI Guojie SONG chuan shi School of Intelligence Science and Technology Peking University School of Computer Science Beijing University of Posts and Telecommunications

Different nodes in a graph neighborhood generally yield different importance. In previous work of graph convolutional networks(GCNs), such differences are typically modeled with attention ***, as we prove in our paper, soft attention weights suffer from undesired smoothness large neighborhoods(not to be confused with the oversmoothing effect in deep GCNs). To address this weakness, we introduce a novel framework of conducting graph convolutions, where nodes are discretely selected among multi-hop neighborhoods to construct adaptive receptive fields(ARFs). ARFs enable GCNs to get rid of the smoothness of soft attention weights, as well as to efficiently explore long-distance dependencies in *** further propose GRARF(GCN with reinforced adaptive receptive fields) as an instance, where an optimal policy of constructing ARFs is learned with reinforcement learning. GRARF achieves or matches state-of-theart performances on public datasets from different domains. Our further analysis corroborates that GRARF is more robust than attention models against neighborhood noises.

关键词： graph neural networks receptive field reinforcement learning

Using interacting multiple model particle filter to track airborne targets hidden in blind Doppler

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第8期8卷 1277-1282页

作者： DU shi-chuan shi Zhi-guo ZANG Wei CHEN Kang-sheng Department of Information and Electronie Engineering Zhejiang University Hangzhou 310027 China

In airborne tracking,the blind Doppler makes the target undetectable,resulting in tracking difficulties. In this paper,we studied most possible blind-Doppler cases and summed them up into two types:targets' intentional tangential flying to radar and unintentional flying with large tangential speed. We proposed an interacting multiple model(IMM) particle filter which combines a constant velocity model and an acceleration model to handle maneuvering motions. We compared the IMM particle filter with a previous particle filter solution. Simulation results showed that the IMM particle filter outperforms the method in previous works in terms of tracking accuracy and continuity.

关键词： Interacting multiple model Particle filter Blind Doppler

Autonomic discovery of subgoals in hierarchical reinforcement learning

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The Journal of China Universities of Posts and Telecommunications 2014年第5期21卷 94-104页

作者： XIAO Ding LI Yi-tong shi chuan School of Computer Science Beijing University of Posts and Telecommunications

Option is a promising method to discover the hierarchical structure in reinforcement learning （RL） for learning acceleration. The key to option discovery is about how an agent can find useful subgoals autonomically among the passing trails. By analyzing the agent＇s actions in the trails, useful heuristics can be found. Not only does the agent pass subgoals more frequently, but also its effective actions are restricted in subgoals. As a consequence, the subgoals can be deemed as the most matching action-restricted states in the paths. In the grid-world environment, the concept of the unique-direction value reflecting the action-restricted property was introduced to find the most matching action-restricted states. The unique-direction-value （UDV） approach is chosen to form options offline and online autonomically. Experiments show that the approach can find subgoals correctly. Thus the Q-learning with options found on both offline and online process can accelerate learning significantly.

关键词： hierarchical reinforcement learning option Q-learning subgoal UDV

Research Status and Strategies for Cognitive Function in Schizophrenia

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上海精神医学 2018年第3期30卷 199-201页

作者： Ke MA chuan shi Peking University Sixth Hospital Beijing China

Cognition is divided into neurocognition and social cognition,both of which are interconnected with each other and yet are mutually ***,which is based on neuroanatomical structures,function connections,neuroelectrophy... 详细信息

关键词：精神分裂症认知功能神经解剖学神经功能认知过程生物学社会大脑

Arabidopsis Plants Having Defects in Nonsense-mediated mRNA Decay Factors UPF1, UPF2, and UPF3 Show Photoperiod-dependent Phenotypes in Development and Stress Responses

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Journal of Integrative Plant Biology 2012年第2期54卷 99-114页

作者： chuan shi Ian T. Baldwin Jianqiang WU Department of Medical Engineering and Biotechnology University of Applied Sciences Jena 07745 Germany Department of Molecular Ecology Max Planck Institute for Chemical Ecology 07745 Germany

Nonsense-mediated mRNA decay （NMD） is an important mRNA quality surveillance pathway in all eukaryotes that eliminates aberrant mRNAs derived from various sources. Three NMD factor proteins, UPF1, UPF2, and UPF3 are required for the NMD process and were found to be also involved in certain stress responses in mammalian and yeast cells. Using Arabidopsis thaliana mutants of UPF1 and UPF3 and UPF2-silenced lines （irUPF2）, we examined the involvement of UPF1, UPF2, and UPF3 in development and in response to stresses, wounding and infection by Pseudomonas syringae pv. tomato strain DC3000. Under the long （16 h） photoperiod condition, Arabidopsis having a defect in NMD factors exhibited altered morphologies of various organs, disturbed homeostasis of wounding-induced jasmonic acid and pathogen-elicited salicylic acid, and abnormal wounding- and methyl jasmonate-induced changes in the transcript levels of two defense-related genes, LOX2 and VSP2. Importantly, when plants were cultivated under the short （10 h） photoperiod condition, mutants of UPF1 and UPF3 and irUPF2 showed smaller differences from the wild-type plants in growth and stress-induced responses. These data suggest a complex regulatory network, likely composed of light signaling and NMD factor-mediated pathways, in influencing plant development and adaption to environmental stresses.

关键词： Development nonsense-mediated mRNA decay pathogen photoperiod wounding

Graph foundation model

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Frontiers of Computer Science 2024年第6期18卷 291-293页

作者： chuan shi Junze CHEN Jiawei LIU Cheng YANG School of Computer Science Beijing University of Posts and TelecommunicationsBeijing 100876China

1 *** learning,dedicated to uncovering and discovering information within graph data,has continually evolved and transformed its learning paradigms since its ***,shallow learning methods like random walk[1]and matrix ... 详细信息

关键词： transformed foundation factorization

Molecular modulating of cobalt phthalocyanines on aminofunctionalized carbon nanotubes for enhanced electrocatalytic CO_(2)conversion

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Nano Research 2023年第3期16卷 3649-3657页

作者： Huajian Xu Huizhu Cai Linxia Cui Limei Yu Rui Gao chuan shi State Key Laboratory of Fine Chemicals College of Chemical EngineeringDalian University of TechnologyDalian 116024China College of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhot 010021China

Metal porphyrins and metal phthalocyanines(Pc)constitute a promising class of metal molecular catalysts(MMCs)for efficient CO_(2)-to-CO electrocatalytic conversion due to their well-defined molecular *** to adjust the local coordination and electronic environment of the metal center and enhance the molecular-level dispersion of the active components remains as great challenges for further improving the ***,a cobalt(II)Pc(CoPc)-COOH/carbon nanotube(CNT)-NH_(2)hybrid catalyst was rationally designed by clicking the CoPc-COOH molecules onto the surface of CNT-NH_(2)through amidation *** novel hybrid catalyst exhibited the enhanced current density of 22.4 mA/cm2 and CO selectivity of 91%at−0.88 V *** hydrogen electrode(RHE)in the CO_(2)electroreduction,as compared with CoPc-COOH/CNT and CoPc/CNT *** superior activity was ascribed to the charge transfer induced by introduction of-COOH and-NH_(2)functional groups to CoPc and CNT,respectively,facilitating the active centers of CoI being generated at lower potentials,and leading to the highest turnover frequency(TOF)being obtained over the CoPc-COOH/CNT-NH_(2)hybrid *** inherent directivity and saturability of covalent bonds formed via the amidation reaction ensure not only a higher density of Co active centers,but also an improved stability for CO_(2)reduction reaction(CO_(2)RR).The present study represents an effective strategy for improving MMCs performance by molecular modulating of metal phthalocyanines on functionalized carbon substrates directed by click confinement chemistry.

关键词： electrocatalytic CO_(2)reduction cobalt tetracarboxylphthalocyanine amino functionalized carbon nanotubes amidation

Entity set expansion in knowledge graph:a heterogeneous information network perspective

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Frontiers of Computer Science 2021年第1期15卷 127-138页

作者： chuan shi Jiayu DING Xiaohuan CAO Linmei HU Bin WU Xiaoli LI School of Computer Science Beijing University of Posts and TelecommunicationsBeijing 100876China Institute for Infocomm Research Agency for ScienceTechnology and ResearchSingapore 138632Singapore

Entity set expansion(ESE)aims to expand an entity seed set to obtain more entities which have common *** is important for many applications such as dictionary con-struction and query *** ESE methods relied heavily on the text and Web information of ***,some ESE methods employed knowledge graphs(KGs)to extend ***,they failed to effectively and fficiently utilize the rich semantics contained in a KG and ignored the text information of entities in *** this paper,we model a KG as a heterogeneous information network(HIN)containing multiple types of objects and ***-grained multi-type meta paths are proposed to capture the hidden relation among seed entities in a KG and thus to retrieve candidate *** we rank the entities according to the meta path based structural ***,to utilize the text description of entities in Wikipedia,we propose an extended model CoMeSE++which combines both structural information revealed by a KG and text information in Wikipedia for *** experiments on real-world datasets demonstrate that our model achieves better performance by combining structural and textual information of entities.

关键词： entity set expansion knowledge graph heterogeneous information network multi-type meta path

Bismuth Mediated Organic Reaction: A Convenient Method for the Synthesis of Allylic (Benzylic) Selenides and α-Organylselenocarbonyl Compounds in Aqueous Media

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Chinese Chemical Letters 2000年第12期11卷 1037-1040页

作者： Pei Pei SUN Ya Ping XIAO Bao chuan shi Department of Chemistry Nanjing Normal UniversityNanjing 210097

In the presence of BiCl3/Al or BiCl3/Fe, in THF-H2O, allylic (benzylic) bromides or α-bromoketones react with diorganyl diselenides to give allylic (benzylic) selenides orα-organylselenocarbonyl compounds respective... 详细信息

关键词： Bismuth allylic ( benzylic) selenides,α-organylselenocarbonyl compounds synthesis.