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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1410-1423页

作者： Xiangmin Tan Chunyan Hu Guanzhen Cao Qinglai wei wei Li Bo Han Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190 School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing 100049China Institute of Automation Chinese Academy of SciencesBeijing 100190 School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China IEEE

In this paper,fixed-time consensus tracking for mul-tiagent systems(MASs)with dynamics in the form of strict feed-back affine nonlinearity is addressed.A fixed-time antidistur-bance consensus tracking protocol is proposed,which consists of a distributed fixed-time observer,a fixed-time disturbance observer,a nonsmooth antidisturbance backstepping controller,and the fixed-time stability analysis is conducted by using the Lyapunov theory *** paper includes three main ***,a distributed fixed-time observer is developed for each follower to obtain an estimate of the leader’s output by utilizing the topology of the communication ***,a fixed-time disturbance observer is given to estimate the lumped disturbances for feedforward ***,a nonsmooth antidisturbance backstepping tracking controller with feedforward compensation for lumped disturbances is *** order to mitigate the“explosion of complexity”in the tradi-tional backstepping approach,we have implemented a modified nonsmooth command filter to enhance the performance of the closed-loop *** simulation results show that the pro-posed method is effective.

关键词： Antidisturbance backstepping consensus tracking fixed-time stability multiagent system(MASs) strict feedback affine nonlinear systems.

CRABP1-mediated non-canonical retinoic acid signaling in motor neurons and neural stem cells

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Neural Regeneration Research 2024年第6期19卷 1169-1170页

作者： Li-Na wei Department of Pharmacology University of Minnesota Medical SchoolMinneapolisMNUSA

Retinoic acid(RA),the active metabolite of vitamin A(the retinoids),elicits a wide spectrum of biological activities critical to the development and health of most of the organ systems including the nervous systems(Corcoran et al.,2002).The effects of RA are mediated by two very distinct pathways;the first is manifested in the nucleus by binding to a large family of nuclear RA receptors(RARs)to regulate proper expression of RAtargeted genes.

关键词： canonical spectrum critical

A novel cascaded H-bridge photovoltaic inverter with flexible arc suppression function

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Global Energy Interconnection 2024年第4期7卷 513-527页

作者： Junyi Tang wei Gao College of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108P.R.China

This paper presents a novel approach that simultaneously enables photovoltaic(PV)inversion and flexible arc suppression during single-phase grounding *** compensate for ground currents through an arc-elimination function,while outputting a PV direct current(DC)power *** method effectively reduces the residual grounding *** reduce the dependence of the arc-suppression performance on accurate compensation current-injection models,an adaptive fuzzy neural network imitating a sliding mode controller was *** online adaptive adjustment law for network parameters was developed,based on the Lyapunov stability theorem,to improve the robustness of the inverter to fault and connection ***,a new arc-suppression control exit strategy is proposed to allow a zerosequence voltage amplitude to quickly and smoothly track a target value by controlling the nonlinear decrease in current and reducing the regulation *** results showed that the proposed method can effectively achieve fast arc suppression and reduce the fault impact current in single-phase grounding *** to other methods,the proposed method can generate a lower residual grounding current and maintain good arc-suppression performance under different transition resistances and fault locations.

关键词： Photovoltaic inverter Flexible arc suppression Adaptive control Fuzzy neural network Sliding mode control Exit strategy

Enhance the Performance of Directional Feature-based Palmprint Recognition by Directional Response Stability Measurement

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Machine Intelligence Research 2024年第3期21卷 597-614页

作者： Haitao Wang wei Jia School of Computer Science and Information Engineering Hefei University of TechnologyHefei230009China

Palmprint recognition is an emerging biometrics technology that has attracted increasing attention in recent years. Many palmprint recognition methods have been proposed, including traditional methods and deep learning-based methods. Among the traditional methods, the methods based on directional features are mainstream because they have high recognition rates and are robust to illumination changes and small noises. However, to date, in these methods, the stability of the palmprint directional response has not been deeply studied. In this paper, we analyse the problem of directional response instability in palmprint recognition methods based on directional feature. We then propose a novel palmprint directional response stability measurement (DRSM) to judge the stability of the directional feature of each pixel. After filtering the palmprint image with the filter bank, we design DRSM according to the relationship between the maximum response value and other response values for each pixel. Using DRSM, we can judge those pixels with unstable directional response and use a specially designed encoding mode related to a specific method. We insert the DRSM mechanism into seven classical methods based on directional feature, and conduct many experiments on six public palmprint databases. The experimental results show that the DRSM mechanism can effectively improve the performance of these methods. In the field of palmprint recognition, this work is the first in-depth study on the stability of the palmprint directional response, so this paper has strong reference value for research on palmprint recognition methods based on directional features.

关键词： Biometrics palmprint recognition directional response stability directional coding-based methods directional feature

SOLVING SYSTEMS OF PHASELESS EQUATIONS VIA RIEMANNIAN OPTIMIZATION WITH OPTIMAL SAMPLING COMPLEXITY

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Journal of Computational Mathematics 2024年第3期42卷 755-783页

作者： Jianfeng Cai ke wei Department of Mathematics Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARChina School of Data Science Fudan UniversityShanghaiChina

A Riemannian gradient descent algorithm and a truncated variant are presented to solve systems of phaseless equations|Ax|^(2)=*** algorithms are developed by exploiting the inherent low rank structure of the problem based on the embedded manifold of rank-1 positive semidefinite *** recovery guarantee has been established for the truncated variant,showing that the algorithm is able to achieve successful recovery when the number of equations is proportional to the number of *** key ingredients in the analysis are the restricted well conditioned property and the restricted weak correlation property of the associated truncated linear *** evaluations show that our algorithms are competitive with other state-of-the-art first order nonconvex approaches with provable guarantees.

关键词： Phaseless equations Riemannian gradient descent Manifold of rank-1 and positive semidefinite matrices Optimal sampling complexity

Is the Cape Stone Forest in Shantou City formed by wave erosion? A comparison of the pedestal rocks on the coasts and the mountains of Queshi in eastern Guangdong, China

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Journal of Mountain Science 2024年第5期21卷 1447-1463页

作者： CHEN Min WANG wei School of Geography South China Normal UniversityGuangzhou 510631China

Cape Stone Forest is a group of granite rock pillars(pedestal rocks) towering over Shilin Lake, on the southern shore of Shantou Bay in eastern Guangdong, China. The rock pillars were previously identified as sea stacks because they have marine notch-like concave sidewalls at their base, and more importantly, the lake is immediately adjacent to the bay, which is exposed to the open sea. However, rock pillars similar in shape and size can also be found at the top of Queshi Mountain, which is only about 300 meters northwest of the lake and about 85 meters above sea level. Therefore, the marine origin of Cape Stone Forest is seriously questioned. In this study, 3D imagery and drone technology were used to collect data in the investigations without direct manual measurements in the water or on the mountain. It shows that the concave sidewalls of the rock pillars in the lake and on the mountains occur at different heights and are exposed to different directions, while a natural sea stack on Mayu Island at the mouth of Shantou Bay has a horizontal notch parallel to the sea level, although the granite rock of the sea stack is the same as that of the lake and the mountains. The eastern side of the island, where the sea stack is located, is exposed to the open sea but blocks large waves for the rock pillars in the lake. Therefore, the origin of Cape Stone Forest cannot be explained by wave-based mechanisms. The only satisfactory explanation that takes into account all the field evidence is that the narrow rock pillars of the lake and mountain were formed by chemical weathering that penetrated closely the spaced joints of the granite rock, and the notch-like concave sidewalls were formed by more effective chemical weathering at the base of the pillars.

关键词： Pedestal rock Granite Closely spaced joints Wave erosion Chemical weathering

Global Stability to Steady Supersonic Rayleigh Flows in One-Dimensional Duct

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 279-296页

作者： Fenglun wei Jianli LIU Department of Mathematics Shanghai University Newtouch Center for Mathematics of Shanghai University

Heat exchange plays an important role in hydrodynamical systems,which is an interesting topic in theory and *** this paper,the authors consider the global stability of steady supersonic Rayleigh flows for the one-dimensional compressible Euler equations with heat exchange,under the small perturbations of initial and boundary conditions in a finite rectilinear duct.

关键词： Compressible Euler equations Heat exchange Supersonic Rayleigh fow Steady solution Classical solution

Two Applications of the ■■-Hodge Theory

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Chinese Annals of Mathematics,Series B 2024年第1期45卷 137-150页

作者： Dingchang wei Shengmao ZHU Center of Mathematical Sciences Zhejiang UniversityHangzhou 310027China Department of Mathematics Zhejiang Normal UniversityJinhua 321004ZhejiangChina

Using Hodge theory and Banach fixed point theorem,Liu and Zhu developed a global method to deal with various problems in deformation *** this note,the authors generalize Liu-Zhu's method to treat two deformation problems for non-kahler *** apply the ■■-Hodge theory to construct a deformation formula for(p,q)-forms of compact complex manifold under deformations,which can be used to study the Hodge number of complex manifold under *** the second part of this note,by using the ■■-Hodge theory,they provide a simple proof of the unobstructed deformation theorem for the non-kahler Calabi-Yau ■■-manifolds.

关键词： Complex structures Deformations (p,q)-Forms Non-kahler Calabi-Yaumanifolds

Nest decoration:Black feathers prevent Crested Mynas from nest usurpation

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Avian Research 2024年第2期15卷 292-297页

作者： Jinmei Liu wei Liang Ministry of Education key Laboratory for Ecology of Tropical Islands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou571158China

Nests are important structures for birds to raise their offspring and for *** birds incorporate feathers into the nest,since feathers were traditionally thought to serve the function of *** in recent years have considered that some birds place feathers in conspicuous locations in the nest for decoration to trigger a fear response in the *** this study,we investigated whether decorative feathers could deter nest usurpation by Crested Mynas(Acridotheres cristatellus)by manipulating nest box *** results revealed that Crested Mynas preferred black feathers to white feathers as decorations and occupied nest boxes decorated with black feathers significantly less than those decorated with white feathers,suggesting that black decorative feathers in the nest could be more effective in preventing nest usurpation by Crested Mynas and that white decorative feathers may have other *** black feathers in the nest are prominently placed at the edge of the nest to convey the message that“this nest is occupied”or“the owner of this nest has been preyed upon”to visitor Crested Mynas,thus effectively preventing them from usurping the nest at a later stage.

关键词： Extended phenotype Feathers Nest decoration Nest usurpation

2D all-organic perovskites refine flexible electronics

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Science China Materials 2024年第7期67卷 2365-2366页

作者： wei Zhou Bing Chen College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023China

Recent years have witnessed a paradigm shift with the advent of perovskites,a class of materials with a distinct CaTiO_(3)-type crystalline structure that show remarkable promise across a wide array of applications,including photovoltaics,photodetectors,lighting,lasers,and so *** them,the development of two-dimensional(2D)perovskites has garnered significant attention due to their tunable structures(mainly Dion-Jacobson and Ruddlesden-Popper structures)and enhanced stability in comparison with their 3D counterparts[1].Amidst the burgeoning research on perovskites,on the other side,all-organic perovskites stand out as a particularly intriguing subset[2].Unlike traditional perovskites that typically comprise all-inorganic(e.g.,CsPbBr_(3))or organic-inorganic hybrid components(e.g.,(PEA)_(2)PbI_(4)),all-organic perovskites are composed entirely of carbon-or nitrogen-based molecules.

关键词： perovskite inorganic entirely