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g-Besselian Frames in Hilbert Spaces

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Acta Mathematica Sinica,English Series 2010年第11期26卷 2117-2130页

作者： Ming ling DING yu Can ZHU College of Computer and Information Fujian Agriculture and Forestry University Fuzhou 350002 P. R. China Department of Mathematics Fuzhou University Fuzhou 350108 P. R. China

In this paper, we introduce the concept of a g-Besselian frame in a Hilbert space and discuss the relations between a g-Besselian frame and a Besselian frame. We also give some characterizations of g-Besselian frames. In the end of this paper, we discuss the stability of g-Besselian frames. Our results show that the relations and the characterizations between a g-Besselian frame and a Besselian frame are different from the corresponding results of g-frames and frames.

关键词： g-frame Besselian frame g-Besselian frame stability

A Levenberg–Marquardt Method for Solving the Tensor Split Feasibility Problem

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Journal of the Operations Research Society of China 2021年第4期9卷 797-817页

作者： yu-Xuan Jin Jin-ling Zhao School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China

This paper considers the tensor split feasibility *** C and Q be non-empty closed convex set and A be a semi-symmetric *** tensor split feasibility problem is to find x∈C such that Axm−1∈*** we simply take this problem as a special case of the nonlinear split feasibility problem,then we can directly get a projection method to solve ***,applying this kind of projection method to solve the tensor split feasibility problem is not so *** we propose a Levenberg–Marquardt method to achieve higher *** analyses are conducted,and some preliminary numerical results show that the Levenberg–Marquardt method has advantage over the common projection method.

关键词： Tensor Split feasibility problem Semi-symmetric Projection Levenberg-Marquardt method

Longitudinal dispersion coefficients of pollutants in compound channels with vegetated floodplains

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Journal of Hydrodynamics 2019年第4期31卷 740-749页

作者： Li Gu Xin-xin Zhao ling-hang Xing Zi-nan Jiao zu-lin Hua Xiao-dong Liu Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education College of Environment Hohai University Nanjing 210098 China National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University Nanjing 210098 China Nanjing Guohuan Science and Technology Co. Ltd. Nanjing 210001 China Changjiang River Scientific Research Institute Wuhan 430010 China

The characteristics of the longitudinal dispersion of pollutants in compound channels remain unclear. This study examines the relationships among the vegetation density, the width of the floodplain, the water depth ratio, the cross-sectional mean velocity, and the longitudinal dispersion coefficient of a symmetrical compound channel with a rigid non-submerged vegetated floodplain. The longitudinal dispersion coefficient is found to increase significantly with the presence of vegetation on floodplains, and is positively correlated with the plant density. When the density of the vegetation on the floodplains exceeds a certain value, the dispersion coefficient no longer changes with the vegetation density. The longitudinal dispersion coefficient is found to increase with the increase of the width of the floodplain. Moreover, the combined effects of the mean velocity and the water depth ratio have a positive correlation with the dispersion coefficient. The effects of the vegetation on the longitudinal dispersion coefficient in the channels with various cross-sections are also compared. The compound channels with a vegetated floodplain are found to differ significantly from the channels with a rectangular cross-section.

关键词： Compound channel longitudinal dispersion coefficient relationship vegetated floodplain

The correlation between gut microbiome and atrial fibrillation: pathophysiology and therapeutic perspectives

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Military Medical Research 2024年第5期11卷 697-716页

作者： Na Li ling Wang Lei Li Meng-Zhao Yang Qing-Xiang Wang Xi-Wen Bai Feng Gao Yi-Qiang yuan zu-Jiang yu Zhi-Gang Ren Department of Infectious Diseases the First Affiliated Hospital of Zhengzhou UniversityZhengzhou450052China Jinan Microecological Biomedicine Shandong Laboratory Jinan250000China Department of Cardiovascular Medicine Henan Provincial Chest HospitalZhengzhou450008China Department of Blood Collection Xuchang Blood CenterXuchang461000HenanChina Nanchang University Queen Marry School Nanchang330036China

Regulation of gut microbiota and its impact on human health is the theme of intensive *** incidence and prevalence of atrial fibrillation(AF)are continuously escalating as the global population ages and chronic disease survival rates increase;however,the mechanisms are not entirely *** is gaining awareness that alterations in the assembly,structure,and dynamics of gut microbiota are intimately engaged in the AF *** to advancements in next-generation sequencing technologies and computational strategies,researchers can explore novel linkages with the genomes,transcriptomes,proteomes,and metabolomes through parallel meta-omics approaches,rendering a panoramic view of the culture-independent microbial *** this review,we summarized the evidence for a bidirectional correlation between AF and the gut ***,we proposed the concept of“gut-immune-heart”axis and addressed the direct and indirect causal roots between the gut microbiome and *** intricate relationship was unveiled to generate innovative microbiota-based preventive and therapeutic interventions,which shed light on a definite direction for future experiments.

关键词： Atrial fibrillation(AF) Gut microbiome Meta-omics Metabolites Immunity

Solvent-driven reversible transformation between electrically neutral thiolate protected Ag_(25)and Ag_(26)clusters

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Science China Chemistry 2021年第6期64卷 948-952页

作者： yu-ling Tan ling Yang Tian-Chen yu Hong yu Xin-Yao Wang Ying-Lin Song Zheng Niu Jian-Ping Lang College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Physical Science and Technology Soochow UniversitySuzhou 215006China

Two atom-precise silver nanoclusters[Ag_(25)Cl_2(Tab)_(14)(Ph COO)_(11)(DMF)_4](PF_6)_(12)(Ag_(25),DMF=N,N-dimethylformamide)and[Ag_(26)Cl_2(Tab)_(14)(Ph COO)_(13)(DMAc)_4](PF_6)_(11)(Ag_(26),DMAc=N,N-dimethylacetamide)were synthesized based on the electrically neutral thiolate protective ligand,4-(trimethylammonio)benzenethiolate(Tab).The weak Ag–S interaction in Tab-protected silver nanoclusters allows to insert or leave a single silver atom in the Ag–S skeleton through solvent-trigger core fragmentation and re-arrangement,thereby realizing the reversible conversion of Ag_(25)and Ag_(26)for the first time.

关键词： silver nanocluster electrically neutral thiolate reversible transformation

A power conversion system for PMSG-based WECS operating with fully-controlled current-source converters

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第3期15卷 232-240页

作者： Jian-yu BAO Wei-bing BAO yu-ling LI Ningbo Institute of Technology Zhejiang University Zhijiang College Zhejiang University of Technology College of Electrical Engineering Zhejiang University

We propose a new power conversion system for a permanent magnet synchronous generator(PMSG) based grid-connected wind energy conversion system(WECS) operating with fully-controlled back-to-back current-source converters. On the generator side, two independent current-source rectifiers(CSRs) with space-vector pulse width modulation(SVPWM) are employed to regulate and stabilize DC-link currents. Between DC-link and the electrical grid, a direct-type three-phase five-level current-source inverter(CSI) is inserted as a buffer to regulate real and reactive power fed to the grid and thus adjusts the grid side power-factor. We also present a current-based maximum power point tracking(MPPT) scheme, which helps the generator extract the maximum power through closed-loop regulation of the generator speed. By applying the multilevel modulation and control strategies to the grid-side five-level CSI, a multilevel output current waveform with less distortion is produced, and the bulk requirement of the output capacitor filter to eliminate the harmonic current is reduced. All the proposed concepts are verified by simulation models built in a PSIM environment.

关键词： Grid-connected Wind energy conversion Current-source rectifier Multilevel current-source inverter

Battery aging-minimal speed control of autonomous heavy-duty electric trucks in adaptation to highway topography and traffic

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Science China(Technological Sciences) 2023年第10期66卷 2942-2957页

作者： ZHANG YongZhi WANG Chun yu QuanQing ZHENG ling College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China School of Mechanical Engineering Sichuan University of Science and EngineeringZigong 643000China School of Automotive Engineering Harbin Institute of TechnologyWeihai 264209China

The development of battery electric(BE)heavy-duty trucks(HDTs)is highly limited to the short cycling life of *** this paper,we propose a battery aging-conscious control strategy for extended battery life by optimizing the speed trajectory of BE HDT.A state-space model is constructed by connecting the vehicle dynamics and battery state of charge,and a mechanism-based aging model of battery is then introduced to formulate the optimization problem for minimal battery aging and energy *** optimization problem is solved within a model predictive control framework for the real-time speed control of the vehicle.A non-cooperative platooning controller is further developed for the vehicle in adaptation to the traffic,where the intervehicular distance is controlled for reducing the air drag coefficient so that both the energy consumption and battery aging are *** results show that for the single-vehicle controller,the battery degradation and energy consumption are,respectively,reduced by up to 25.7%and 3.2%compared with the cruise control *** on the non-cooperative controller,the HDT is able to follow preceding vehicles with different parameters with battery aging and energy consumption further,respectively,reduced by 2%–5%and 9%–10%compared with those of the single-vehicle controller.

关键词： electric trucks speed trajectory planning battery aging model predictive control non-cooperative platooning

Exploring the potential of constructing a hybrid supercapacitor with FeCoNi-LDH porous material containing oxygen vacancies for high-performance energy storage applications

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Nano Research 2024年第9期17卷 8134-8144页

作者： Jihao Su ling Yang Dengbin yu Shaojun Dong State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China College of Chemistry Jilin UniversityChangchun 130022China University of Science and Technology of China Hefei 230026China

A significant challenge in developing high-performance hybrid supercapacitors(HSCs)is the need to reasonably construct advanced architectures that consist of various components and exhibit superior electrochemical capacitance *** FeCoNi-layered double hydroxide(FeCoNi-LDH)porous material has a specific capacitance of 1960 F·g^(-1)when used as the anode material at 1 A·g^(-1).The FeCoNi-LDH material exhibits nanoplates with a distinct spindle morphology on their *** to the combined action of the three metals and abundant oxygen vacancies,they exhibit unique rate performance and cycle *** electronic structure of LDH and the regulation of oxygen vacancy were confirmed by density functional theory(DFT)*** suggests that the strength of hydroxide can reduce the energy required for oxygen vacancy formation in FeCoNi-LDH nanosheets and enhance ion and charge transfer,as well as electrolyte adsorption on the electrode *** FeCoNi-LDH//activated carbon(AC)HSC has an energy density of 53.2 Wh·kg^(-1)at a power density of 800 W·kg^(-1),surpassing other devices composed of comparable materials during the same *** study made significant advances in the design and synthesis of a ternary LDH porous structure with distinct oxygen vacancies,as well as its potential application in electrochemical energy storage.

关键词： oxygen vacancy FeCoNi-layered double hydroxide(FeCoNi-LDH) theory calculation electrode material hybrid supercapacitor

A nonlocal dispersal and time delayed HIV infection model with general incidences

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 448-457页

作者： WU Peng ZHANG yu-huai WANG ling School of Sciences Hangzhou Dianzi UniversityHangzhou 310018China School of Humanities and Management Zhejiang Chinese Medical UniversityHangzhou 311402China Public Foundational Courses Department Nanjing Vocational University of Industry TechnologyNanjing 210023China

Biologically,because of the impact of reproduction period and nonlocal dispersal of HIV-infected cells,time delay and spatial heterogeneity should be *** this paper,we establish an HIV infection model with nonlocal dispersal and infection ***,applying the theory of Fourier transformation and von Foerster rule,we transform the model to an integrodifferential equation with nonlocal time delay and *** well-posedness,positivity,and boundedness of the solution for the model are studied.

关键词： HIV model nonlocal dispersal time delay general incidences