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Nano-Micro Letters 2025年第2期17卷 376-386页

作者： Wei-Min Qin Zhongliang Li Wen‑Xia Su Jia‑Min Hu Hanqin Zou Zhixuan Wu Zhiqin Ruan Yue‑peng cai Kang Li Qifeng Zheng School of Chemistry South China Normal UniversityGuangzhou 510006People’s Republic of China Key Laboratory of Functional Metal‑Organic Compounds of Hunan Province College of Chemistry and Material ScienceHengyang Normal UniversityHengyang 421008People’s Republic of China Guangzhou Key Laboratory of Energy Conversion and Energy Storage Materials Guangzhou 510006People’s Republic of China

Porous organic cages(POCs)with permanent porosity and excellent host–guest property hold great potentials in regulating ion transport behavior,yet their feasibility as solid-state electrolytes has never been testified in a practical ***,we design and fabricate a quasi-solid-state electrolyte(QSSE)based on a POC to enable the stable operation of Li-metal batteries(LMBs).Benefiting from the ordered channels and cavity-induced anion-trapping effect of POC,the resulting POC-based QSSE exhibits a high Li+transference number of 0.67 and a high ionic conductivity of 1.25×10^(−4) S cm^(−1) with a low activation energy of 0.17 *** allow for homogeneous Li deposition and highly reversible Li plating/stripping for over 2000 *** a proof of concept,the LMB assembled with POC-based QSSE demonstrates extremely stable cycling performance with 85%capacity retention after 1000 ***,our work demonstrates the practical applicability of POC as SSEs for LMBs and could be extended to other energy-storage systems,such as Na and K batteries.

关键词： Porous organic cage Cavity-induced anion-trapping Quasi-solid-state electrolyte Homogeneous Li+flux Lithium metal battery

Research on optimal guaranteed cost control of flexible spacecraft

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Journal of Systems Engineering and Electronics 2008年第5期19卷 988-995页

作者： Wang Qingchao cai peng School of Astronautics Harbin Inst. of Technology Harbin 150001 P. R. China

This article is concerned with the modeling and control problems of the flexible spacecraft. First, the state observer is designed to estimate the vibration mode on the basis of free vibration models, Then, an optimal guaranteed cost controller is proposed to stabilize system attitude and damp the vibration of the flexible beam at the same time. Numerical simulation examples show the feasibility and validity of the proposed method.

关键词： spacecraft attitude control Euler-Bernoulli beam optimal guaranteed cost control.

Efficient and stable quorum-based log replication and replay for modern cluster-databases

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Frontiers of Computer Science 2022年第5期16卷 143-158页

作者： Donghui WANG peng cai Weining QIAN Aoying ZHOU School of Data Science and Engineering East China Normal UniversityShanghai 200062China

The modern in-memory database(IMDB)can support highly concurrent on-line transaction processing(OLTP)workloads and generate massive transactional logs per ***-based replication protocols such as Paxos or Raft have been widely used in the distributed databases to offer higher availability and ***,it is non-trivial to replicate IMDB because high transaction rate has brought new ***,the leader node in quorum replication should have adaptivity by considering various transaction arrival rates and the processing capability of follower ***,followers are required to replay logs to catch up the state of the leader in the highly concurrent setting to reduce visibility ***,modern databases are often built with a cluster of commodity machines connected by low configuration networks,in which the network anomalies often *** this case,the performance would be significantly affected because the follower node falls into the long-duration exception handling process(e.g.,fetch lost logs from the leader).To this end,we build QuorumX,an efficient and stable quorum-based replication framework for IMDB under heavy OLTP *** combines critical path based batching and pipeline batching to provide an adaptive log propagation scheme to obtain a stable and high performance at various ***,we propose a safe and coordination-free log replay scheme to minimize the visibility gap between the leader and follower *** further carefully design the process for the follower node in order to alleviate the influence of the unreliable network on the replication *** evaluation results with the YCSB,TPC-C and a realistic microbenchmark demonstrate that QuorumX achieves the performance close to asynchronous primary-backup replication and could always provide a stable service with data consistency and a low-level visibility gap.

关键词： log replication log replay consensus protocol high performance high availability quorum unreliable network packet loss

Accurate and efficient follower log repair for Raft-replicated database systems

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Frontiers of Computer Science 2021年第2期15卷 91-103页

作者： Jinwei GUO peng cai Weining QIAN Aoying ZHOU School of Data Science and Engineering East China Normal UniversityShanghai200062China

State machine replication has been widely used in modern cluster-based database *** commonly deployed configurations adopt the Raft-like consensus protocol,which has a single strong leader which replicates the log to other *** the followers can handle read requests and many real workloads are usually read-intensive,the recovery speed of a crashed follower may significantly impact on the *** from traditional database recovery,the recovering follower needs to repair its local log *** Raft protocol takes many network round trips to do log comparison between leader and the crashed *** reduce network round trips,an optimization method is to truncate the follower’s uncertain log entries behind the latest local commit point,and then to directly fetch all committed log entries from the leader in one round ***,if the commit point is not persisted,the recovering follower has to get the whole log from the *** this paper,we propose an accurate and efficient log repair(AELR)algorithm for follower *** is more robust and resilient to follower failure,and it only needs one network round trip to fetch the least number of log entries for follower *** approach is implemented in the open source database system *** experimentally show that the system adopting AELR has a good performance in terms of recovery time.

关键词： Raft high availability log replication log repair

FBCRI Based Real-time Path Planning for Unmanned Aerial Vehicles in Unknown Environments with Uncertainty

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机器人 2013年第6期35卷 641-650页

作者： LIU Wei HAO peng ZHENG Zheng cai Kaiyuan School of Automation Science and Electrical Engineering Beihang University Science and Technology on Aircraft Control Laboratory High-Tech Institute of Xi'an

This paper presents an FBCRI(feedback based compositional rule of inference)based novel path planning method to satisfy the requirements of real-time navigation,smoothness optimization and probabilistic obstacle *** local path-searching behaviors in regional ranges and global goal-seeking behaviors in holistic ranges,the method infers behavior weights using fuzzy reasoning embedded with feedback,and then coordinates the behaviors to generate new reference *** view of the deterministic decisions and the uncertain states of a UAV(unmanned air vehicle),chance constraints are adopted to probabilistically guarantee the UAV’s safety at a required *** results in representative scenes prove that the method is able to rapidly generate convergent paths in obstacle-rich environments,as well as highly improve the path quality with respect to smoothness and probabilistic safety.

关键词： unmanned aerial vehicle path planning fuzzy reasoning FBCRI(feedback based compositional rule of inference) uncertainty

What emotion dimensions can affect working memory performance in healthy adults?A review

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World Journal of Clinical Cases 2022年第2期10卷 401-411页

作者： Tian-Ya Hou Wen-peng cai Faculty of Psychology The Second Military Medical UniversityShanghai 200433China

Due to the critical roles of emotion and working memory in our daily activities,a great deal of attention has been given to how emotion influences working memory *** the association between emotion and working memory is relatively well established,whether mood enhances or impairs working memory performance remains *** present review provides a relatively representative overview of the research on the effect of different dimensions of emotion on working memory among healthy adults spanning a 30-year *** findings show that the valence,arousal and motivational dimensions of emotion could all exert an impact on working memory *** impact of emotion on working memory might be modulated by task relevance,emotion type,working memory paradigms and individual *** vast majority of the studies regarding the effect of emotion on working memory performance focused on the impact of negatively valenced affect and yielded highly contradictory *** impacts of arousal and motivation on working memory have been less explored,and inconsistent findings have also been *** explanations are *** research on the effect of certain dimensions of emotion on working memory has suffered from a lack of control of other emotional dimensions,and different aspects of working memory have been investigated by various *** for further studies should include the exploration of specific dimensions of emotion on different aspects of working memory,with the other dimensions being well controlled.

关键词： Working memory Emotion Valence Arousal Motivation Review

COOPERATIVE CLUSTERING BASED ON GRID AND DENSITY

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Chinese Journal of Mechanical Engineering 2006年第4期19卷 544-547页

作者： HU Ruifei YIN Guofu TAN Ying cai peng School of Manufacturing Science and Engineering Sichuan University Chengdu 610065 China

Based on the analysis of features of the grid-based clustering method-clustering in quest （CLIQUE） and density-based clustering method-density-based spatial clustering of applications with noise （DBSCAN）, a new clustering algorithm named cooperative clustering based on grid and density （CLGRID） is presented. The new algorithm adopts an equivalent rule of regional inquiry and density unit identification. The central region of one class is calculated by the grid-based method and the margin region by a density-based method. By clustering in two phases and using only a small number of seed objects in representative units to expand the cluster, the frequency of region query can be decreased, and consequently the cost of time is reduced. The new algorithm retains positive features of both grid-based and density-based methods and avoids the difficulty of parameter searching. It can discover clusters of arbitrary shape with high efficiency and is not sensitive to noise. The application of CLGRID on test data sets demonstrates its validity and higher efficiency, which contrast with tradi- tional DBSCAN with R tree.

关键词： Data mining Clustering Seed object

Experimental and theoretical study of coupled influence of flow velocity increment and particle size on particle retention and release in porous media

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Water Science and Engineering 2017年第3期10卷 236-245页

作者： Xing-xin Chen Qi-peng cai Zhong-han Wu School of Transportation Southeast University School of Civil Engineering Huaqiao University School of Civil Engineering Beijing Jiaotong University

Experimental and theoretical studies were carried out to investigate the coupled influence of flow velocity increment and particle size on the retention and release of particles in porous media. Particle release was examined through measurement of changes in effluent particle concentrations, and particle retention was assessed through measurement of the final spatial distribution of particles remaining in the soil columns after the experiments. Particle release curves were simulated using a convection-dispersion model that includes the instantaneous release of the line source. Fitted model parameters were used to gain insights into the mechanisms that control particle retention and release. When the flow velocity increment was 0.0435 cm/s, the peak concentration of particles decreased with increasing flow velocity until the latter approached a critical level, beyond which the particle concentration increased. Particle wedging and fouling were considered the primary mechanisms that controlled particle retention and release beyond the critical particle velocity. In experiments with large flow velocity increments, small particles exhibited lower particle mass fraction than large particles as particle wedging and fouling increased with particle size. The range of longitudinal dispersivity decreased with an increasing particle size and flow velocity increment. Moreover, the mean particle velocity increased with the mean interstitial fluid velocity. The mean particle velocity profile was highly sensitive to the particle size at low velocity increments. In general,particle release rates increased with both flow velocity and velocity increment. The mass of the released particles provides further evidence that particle wedging and fouling are the major factors that control particle release in sand columns.

关键词： Particle Porous media Retention Release Hydrodynamic force

A Note on Harnack Type Inequality for the Gaussian Curvature Flow

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Acta Mathematicae Applicatae Sinica 2022年第1期38卷 1-4页

作者： cai-peng CHEN Hong-xin GUO Cheng-zhe ZHU Department of mathematics Wenzhou UniversityWenzhou 325035China

In this short note we present a new Harnack expression for the Gaussian curvature flow, which is modeled from the shrinking self similiar solutions. As applications we give alternate proofs of Chow’s Harnack inequali... 详细信息

关键词： Gaussian Curvature flow Harnack inequality

Motion speed modulates walking direction discrimination: The role of the feet in biological motion perception

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Chinese Science Bulletin 2011年第19期56卷 2025-2030页

作者： cai peng YANG XiaoYing CHEN Lin JIANG Yi State Key Laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China Key Laboratory of Mental Health Institute of Psychology Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The human visual system is tuned to the motions of biological entities, which provide potentially vital information for survival. The current study examines the interplay between motion speed and motion direction perception. Following a brief presentation of a point-light walker walking straight ahead or slightly leftward or rightward, observers were asked to quickly judge the walking direction (left or right). Participants showed better direction discrimination when the walker walked at a fast pace compared to a natural or slow pace, and this was not simply due to a difference in motion cycles. Moreover, walking direction sensitivity could be enhanced by increasing the feet motion speed alone, so long as the direction of feet movement was consistent with that of the other body parts. These findings demonstrate that our perception of walking direction is influenced by local motion speed, and highlight the role of the feet in biological motion perception.

关键词：行走方向运动知觉速度调节生物运动速度运动方向视觉系统相互作用