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Science China Mathematics 2024年第11期67卷 2485-2514页

作者： Zefu feng Guangyi Hong Changjiang Zhu School of Mathematical Sciences Chongqing Normal University School of Mathematics South China University of Technology

In this paper,we consider 3D compressible magneto-micropolar fluids without resistivity and spin viscosity in a strip *** prominent character of the governing model is the presence of the microstructure,a linear coupling structure involving derivatives of the velocity fields,which along with the lack of spin viscosity brings several challenges to the *** exploiting the two-tier energy method developed in Guo and Tice(Arch Ration Mech Anal,2013),we prove the global existence of classical solutions to the governing model around a uniform magnetic field that is non-parallel to the horizontal ***,we show that the solution converges to the steady state at an almost exponential rate as time goes to *** of the main ingredients in our analysis,compared with previous works on micropolar fluids,is that we deal with the microstructure by establishing some delicate estimates based on the analysis of the div-curl decomposition,and the coupling between the fluid velocity and the vorticity of angular velocity.

关键词： magneto-micropolar fluids compressible global existence large-time behavior

Role of A-sites in pyrochlore lanthanide ruthenate for electrocatalysis of oxygen evolution reaction

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Journal of Materiomics 2024年第6期10卷 1234-1242页

作者： Hengyu Guo Zhengping Zhang feng Wang State Key Laboratory of Chemical Resource Engineering Beijing Key Laboratory of Electrochemical Process and Technology for MaterialsBeijing University of Chemical TechnologyBeijing100029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing100029China

Developing highly stable and efficient catalysts for oxygen evolution reaction(OER)is extremely important to sustainable energy conversion and storage,but improved efficiency is largely hindered by sluggish reaction *** and bimetal ruthenates have emerged as one of the promising substitutes to replace single-metal ruthenium or iridium oxides,but the fundamental understanding the role of A-site cations is still ***,a family of lanthanides(Ln=all the lanthanides except Pm)are applied to synthesize pyrochlore lanthanide ruthenates(Ln_(2)Ru_(2)O_(7)),and only Ln_(2)Ru_(2)O_(7)(Ln=Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,or Lu)with pure phase can be obtained by the ambient-pressure *** with the perovskite ruthenates(SrRuO_(3))and rutile RuO_(2),the[RuO_(6)]units in these Ln_(2)Ru_(2)O_(7) present the largely distorted configurations and different energy level splitting to prevent the excessive Ru oxidation and dissolution,which leads the primary improvement in the electrocatalytic OER *** the similar crystalline field split states,the charge transfer between[RuO6]units and Ln^(3+)cations also affect catalytic activities,even in the Ln_(2)Ru_(2)O_(7) surface reconstruction during the OER ***,Tb_(2)Ru_(2)O_(7) showed the highest OER performance among all the prepared Ln_(2)Ru_(2)O_(7) with similar morphologies and *** systematic work gives fundamental cognition to rational design of high-performance OER electrocatalysts in proper water electrolysis technologies.

关键词： Pyrochlores Lanthanides Ruthenates Electrocatalysts Oxygen evolution reaction

A Random Fusion of Mix 3D and Polar Mix to Improve Semantic Segmentation Performance in 3D Lidar Point Cloud

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 845-862页

作者： Bo Liu Li feng Yufeng Chen School of Computer Science and Engineering Macao University of Science and TechnologyMacao999078China School of Computer Science and Artificial Intelligence Chaohu UniversityChaohu238000China Institute of Vehicle Information Control and Network Technology Hubei University of Automotive TechnologyShiyan442002China

This paper focuses on the effective utilization of data augmentation techniques for 3Dlidar point clouds to enhance the performance of neural network *** point clouds,which represent spatial information through a collection of 3D coordinates,have found wide-ranging *** augmentation has emerged as a potent solution to the challenges posed by limited labeled data and the need to enhance model generalization *** of the existing research is devoted to crafting novel data augmentation methods specifically for 3D lidar point ***,there has been a lack of focus on making the most of the numerous existing augmentation *** this deficiency,this research investigates the possibility of combining two fundamental data augmentation *** paper introduces PolarMix andMix3D,two commonly employed augmentation techniques,and presents a new approach,named *** of using a fixed or predetermined combination of augmentation methods,RandomFusion randomly chooses one method from a pool of options for each instance or *** innovative data augmentation technique randomly augments each point in the point cloud with either PolarMix or *** crux of this strategy is the random choice between PolarMix and Mix3Dfor the augmentation of each point within the point cloud data *** results of the experiments conducted validate the efficacy of the RandomFusion strategy in enhancing the performance of neural network models for 3D lidar point cloud semantic segmentation *** is achieved without compromising computational *** examining the potential of merging different augmentation techniques,the research contributes significantly to a more comprehensive understanding of how to utilize existing augmentation methods for 3D lidar point *** data augmentation technique offers a simple yet effective method to leverage the diversity of augmentation techniques and boost the ro

关键词： 3D lidar point cloud data augmentation RandomFusion semantic segmentation

Human brain computing and brain-inspired intelligence

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National Science Review 2024年第5期11卷 8-9页

作者： Jianfeng feng Viktor Jirsa Wenlian Lu Institute of Science and Technology for Brain-Inspired Intelligence Fudan University Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence(Fudan University) Ministry of Education Shanghai Center for Mathematical Sciences Fudan University Department of Computer Science University of Warwick Zhangjiang Fudan International Innovation Center Institut de Neurosciences des Systèmes Faculté de Medécine

The relationship between structure, neural activity dynamics and intelligent human brain function is complex and multifaceted with deep roots in several academic disciplines. Its understanding is a fundamental goal of brain research [1] and may indicate the way towards the next generation of artificial intelligence [2]. There are major challenges on the way, several of which are addressed in this Special Topic of National Science Review.

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Asymmetric Partial Hydrosilylation of 2,2-Difluoro-1,3-diketones with Chiral Frustrated Lewis Pairs

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Chinese Journal of Chemistry 2024年第8期42卷 853-857页

作者： Ting Liu Xiangqing feng Haifeng Du Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190 China University of Chinese Academy of Sciences Beijing100049 China

Comprehensive Summary,The asymmetric partial reduction of 1,3-diketones stands as a straightforward pathway to access optically active β-hydroxyketones. In this paper, an asymmetric Piers-type hydrosilylation of 2,2-difluoro-1,3-diketones was successfully realized by using a frustrated Lewis pair of chiral borane and tricyclohexylphosphine as a catalyst, delivering a variety of α,α-difluoro-β-hydroxyketones in high yields with up to 99% ee. Significantly, no over-reduced diol products were observed even with an excess amount of silanes. The product can be conveniently converted to α,α-difluoro-β-hydroxyester or 1,3-anti-diol via an oxidation with m-CPBA or a reduction with DIBAL-H without obvious loss of ee.

关键词： Asymmetric catalysis Hydrosilylation Ketones Frustrated Lewis pairs Chiral boranes

SMSTracker:A Self-Calibration Multi-Head Self-Attention Transformer for Visual Object Tracking

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Computers, Materials & Continua 2024年第7期80卷 605-623页

作者： Zhongyang Wang Hu Zhu feng Liu School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing210003China

Visual object tracking plays a crucial role in computer *** recent years,researchers have proposed various methods to achieve high-performance object *** these,methods based on Transformers have become a research hotspot due to their ability to globally model and contextualize ***,current Transformer-based object tracking methods still face challenges such as low tracking accuracy and the presence of redundant feature *** this paper,we introduce self-calibration multi-head self-attention Transformer(SMSTracker)as a solution to these *** employs a hybrid tensor decomposition self-organizing multihead self-attention transformermechanism,which not only compresses and accelerates Transformer operations but also significantly reduces redundant data,thereby enhancing the accuracy and efficiency of ***,we introduce a self-calibration attention fusion block to resolve common issues of attention ambiguities and inconsistencies found in traditional trackingmethods,ensuring the stability and reliability of tracking performance across various *** integrating a hybrid tensor decomposition approach with a self-organizingmulti-head self-attentive transformer mechanism,SMSTracker enhances the efficiency and accuracy of the tracking *** results show that SMSTracker achieves competitive performance in visual object tracking,promising more robust and efficient tracking systems,demonstrating its potential to providemore robust and efficient tracking solutions in real-world applications.

关键词： Visual object tracking tensor decomposition transformer self-attention

On m-ovoids of finite classical polar spaces with an irreducible transitive automorphism group

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Science China Mathematics 2024年第3期67卷 683-712页

作者： Tao feng Weicong Li Ran Tao School of Mathematical Sciences Zhejiang UniversityHangzhou 310027China Department of Mathematics and National Center for Applied Mathematics Shenzhen Southern University of Science and TechnologyShenzhen 518055China Key Laboratory of Cryptologic Technology and Information Security Ministry of EducationShandong UniversityQingdao 266237China School of Cyber Science and Technology Shandong UniversityQingdao 266237China

In this paper, we classify the m-ovoids of finite classical polar spaces that admit a transitive automorphism group acting irreducibly on the ambient vector space. In particular, we obtain several new infinite familie... 详细信息

关键词： transitive m-ovoids irreducible action finite classical polar spaces primitive divisor

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Improving Diversity with Multi-Loss Adversarial Training in Personalized News Recommendation

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Computers, Materials & Continua 2024年第8期80卷 3107-3122页

作者： Ruijin Xue Shuang feng Qi Wang School of Computer and Cyber Sciences Communication University of ChinaBeijing100024China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China

Users’interests are often diverse and multi-grained,with their underlying intents even more *** captur-ing users’interests and uncovering the relationships between diverse interests are key to news ***,diversity is an important metric for evaluating news recommendation algorithms,as users tend to reject excessive homogeneous information in their recommendation ***,recommendation models themselves lack diversity awareness,making it challenging to achieve a good balance between the accuracy and diversity of news *** this paper,we propose a news recommendation algorithm that achieves good performance in both accuracy and *** most existing works that solely optimize accuracy or employ more features to meet diversity,the proposed algorithm leverages the diversity-aware capability of the ***,we introduce an augmented user model to fully capture user intent and the behavioral guidance they might undergo as a ***,we focus on the relationship between the original clicked news and the augmented clicked ***,we propose an effective adversarial training method for diversity(AT4D),which is a pluggable component that can enhance both the accuracy and diversity of news recommendation *** experiments on real-world datasets confirm the efficacy of the proposed algorithm in improving both the accuracy and diversity of news recommendations.

关键词： News recommendation diversity accuracy data augmentation

Tailoring Iron-Ion Release of Cellulose-Based Aerogel-Coated Iron Foam for Long-Term High-Power Microbial Fuel Cells

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Transactions of Tianjin University 2024年第5期30卷 436-447页

作者： Zhengyang Ni Huitao Yu Haoran Wang Mengmeng Qin feng Li Hao Song Xiangyu Chen Yiyu feng Wei feng School of Material Science and Engineering Tianjin UniversityTianjin 300350China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 100083China

The presence of iron(Fe) has been found to favor power generation in microbial fuel cells(MFCs). To achieve long-term power production in MFCs, it is crucial to effectively tailor the release of Fe ions over extended operating periods. In this study, we developed a composite anode(A/IF) by coating iron foam with cellulose-based aerogel. The concentration of Fe ions in the anode solution of A/IF anode reaches 0.280 μg/mL(Fe^(2+) vs. Fe^(3+) = 61%:39%) after 720 h of aseptic primary cell operation. This value was significantly higher than that(0.198 μg/mL, Fe^(2+) vs. Fe^(3+) = 92%:8%) on uncoated iron foam(IF), indicating a continuous release of Fe ions over long-term operation. Notably, the resulting MFCs hybrid cell exhibited a 23% reduction in Fe ion concentration(compared to a 47% reduction for the IF anode) during the sixth testing cycle(600-720 h). It achieved a high-power density of 301 ± 55 mW/m^(2) at 720 h, which was 2.62 times higher than that of the IF anode during the same period. Furthermore, a sedimentary microbial fuel cell(SMFCs) was constructed in a marine environment, and the A/IF anode demonstrated a power density of 103 ± 3 mW/m^(2) at 3240 h, representing a 75% improvement over the IF anode. These findings elucidate the significant enhancement in long-term power production performance of MFCs achieved through effective tailoring of Fe ions release during operation.

关键词： Microbial fuel cells Coating Fe ions Tailor release Long-term

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On Variational Principles of Metric Mean Dimension on Subsets in Feldman–Katok Metric

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Acta Mathematica Sinica,English Series 2024年第10期40卷 2519-2536页

作者： Kun Mei GAO Rui feng ZHANG School of Mathematics Hefei University of Technology

In this paper, we studied the metric mean dimension in Feldman–Katok(FK for short)metric. We introduced the notions of FK-Bowen metric mean dimension and FK-Packing metric mean dimension on subsets. And we establishe... 详细信息

关键词： 37A35 37B99 Feldman–Katok metric Metric mean dimension variational principle