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Composition Operators on α-Bloch Spaces of the Unit Ball

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Acta Mathematica Sinica,English Series 2007年第11期23卷 1991-2002页

作者： Min zhu ZHANG wen XU Department of Mathematics Nanjing Normal University Nanjing 210097 P. R. China Department of Mathematics Southeast University Nanjing 210096 P. R. China Department of Physics and Mathematics University of Joensuu Fin-80101 Joensuu Finland

The authors characterize the boundedness and compactness of composition operators between α-Bloch spaces of the unit ball.

关键词： α-Bloch space composition operator boundedness compactness

Comparison of three filters in asteroid-based autonomous navigation

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Research in Astronomy and Astrophysics 2014年第3期14卷 329-344页

作者： wen Cui Kai-Jian zhu State Key Laboratory of Astronautic Dynamics Xi’an Satellite Control Center

At present, optical autonomous navigation has become a key technologyin deep space exploration programs. Recent studies focus on the problem of orbit de-termination using autonomous navigation, and the choice of filter is one of the mainissues. To prepare for a possible exploration mission to Mars, the primary emphasisof this paper is to evaluate the capability of three filters, the extended Kalman filter（EKF）, unscented Kalman filter （UKF） and weighted least-squares （WLS） algorithm,which have different initial states during the cruise phase. One initial state is assumedto have high accuracy with the support of ground tracking when autonomous navi-gation is operating; for the other state, errors are set to be large without this *** addition, the method of selecting asteroids that can be used for navigation fromknown lists of asteroids to form a sequence is also presented in this study. The simula-tion results show that WLS and UKF should be the first choice for optical autonomousnavigation during the cruise phase to Mars.

关键词： celestial mechanics asteroids equation of state methods: data analysis techniques: image processing

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao Yu-Gui Peng Peng Wu Zong-Lin Li Xue-Feng zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

Constructing Donor–Acceptor‑Linked COFs Electrolytes to Regulate Electron Density and Accelerate the Li^(+)Migration in Quasi‑Solid‑State Battery

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Nano-Micro Letters 2025年第1期17卷 456-471页

作者： Genfu Zhao Hang Ma Conghui Zhang Yongxin Yang Shuyuan Yu Haiye zhu Yongjiang Sun Hong Guo School of Materials and Energy International Joint Research Center for Advanced Energy Materials of Yunnan ProvinceYunnan UniversityKunming 650091People’s Republic of China Yunnan Yuntianhua Co. LtdR&D CenterKunming 650228People’s Republic of China Southwest United Graduate School Kunming 650091People’s Republic of China

Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective Li^(+)transportation and conduction in solid-state Li metal *** study reports a high-performance solid-state electrolyte thorough D–A-linked covalent organic frameworks(COFs)based on intramolecular charge transfer *** other reported COFbased solid-state electrolyte,the developed concept with D–A-linked COFs not only achieves electronic modulation to promote highly-selective Li^(+)migration and inhibit Li dendrite,but also offers a crucial opportunity to understand the role of electronic density in solid-state Li metal *** introduced strong electronegativity F-based ligand in COF electrolyte results in highlyselective Li^(+)(transference number 0.83),high ionic conductivity(6.7×10^(-4)S cm^(−1)),excellent cyclic ability(1000 h)in Li metal symmetric cell and high-capacity retention in Li/LiFePO_(4)cell(90.8%for 300 cycles at 5C)than substituted C-and N-based *** is ascribed to outstanding D–A interaction between donor porphyrin and acceptor F atoms,which effectively expedites electron transferring from porphyrin to F-based ligand and enhances Li^(+)***,we anticipate that this work creates insight into the strategy for accelerating Li^(+)conduction in high-performance solid-state Li metal batteries through D–A system.

关键词： Electronic modulation engineering Donor-acceptor-linked covalent organic frameworks Quasi-solid-state Li metal battery

UAV-assisted cooperative offloading energy efficiency system for mobile edge computing

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Digital Communications and Networks 2024年第1期10卷 16-24页

作者： Xue-Yong Yu wen-Jin Niu Ye zhu Hong-Bo zhu Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Nanjing210003China Engineering Research Centerof Health Service System Based on Ubiquitous Wireless Networks Ministry of EducationNanjng Universityof Posts and Telecommunications Nanjing210003China

Reliable communication and intensive computing power cannot be provided effectively by temporary hot spots in disaster areas and complex terrain ground *** this has greatly developed the application and integration of UAV and Mobile Edge Computing(MEC)to the Internet of Things(loT).However,problems such as multi-user and huge data flow in large areas,which contradict the reality that a single UAV is constrained by limited computing power,still *** to allowing UAV collaboration to accomplish complex tasks,cooperative task offloading between multiple UAVs must meet the interdependence of tasks and realize parallel processing,which reduces the computing power consumption and endurance pressure of *** the computing requirements of the user terminal,delay constraint of a computing task,energy constraint,and safe distance of UAV,we constructed a UAV-Assisted cooperative offloading energy efficiency system for mobile edge computing to minimize user terminal energy ***,the resulting optimization problem is originally nonconvex and thus,difficult to solve *** tackle this problem,we developed an energy efficiency optimization algorithm using Block Coordinate Descent(BCD)that decomposes the problem into three convex ***,we jointly optimized the number of local computing tasks,number of computing offloaded tasks,trajectories of UAV,and offloading matching relationship between multi-UAVs and multiuser *** results show that the proposed approach is suitable for different channel conditions and significantly saves the user terminal energy consumption compared with other benchmark schemes.

关键词： Computation offloading Internet of things(IoT) Mobile edge computing(MEC) Block coordinate descent(BCD)

Hyperbranched Polyurethane Acrylate Applied to UV Curable Flame Retardant Coatings

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Chemical Research in Chinese Universities 2001年第3期17卷 331-333页

作者： zhu Sheng-Wu SHI wen-Fang State Key Laboratory of Fire Science Department of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026P.R.China

UV curable hyperbranched prepolymers based on amine-ester, ester-amide and ether-amide started with AB_2-type monomers have been prepared by the authors. A series of work on allyl ether maleate hyperbranched polyesters for UV curing coatings by Hult and his colleagues has been reported. However, the UV cured films from those materials are all flammable when attached to fire without addition of flame retardants.

关键词： Flame retardant Polyurethane acrylate Phosphorus UV curing

Estimating Restricted Common Structural Changes for Panel Data

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Acta Mathematicae Applicatae Sinica 2019年第4期35卷 893-908页

作者： Li-wen ZHANG Zhong-yi zhu School of Statistics and Management Shanghai University of Finance and Economics Shanghai 200444 China Department of Statistics School of Management Fudan University Shanghai 200433 China

We consider estimating multiple structural changes occurring at unknown common dates in a panel data regression model with restrictions imposed on the coefficients. We establish the consistency and rate of convergence of the structural change estimates and the asymptotic distribution of the parameter *** is shown that the efficiency of the parameter estimators is increased using the restrictions. An efficient dynamic algorithm is proposed to obtain the break date estimates and the parameter estimates. In addition, we propose a testing procedure for the existence of the change points with the restrictions and derive the asymptotic distribution under the null hypothesis of the test statistics. Simulation studies are presented to investigate the performance of the proposed method in finite samples.

关键词： common structural changes panel data consistency

Design of Fault Detection Observer Based on Hyper Basis Function

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Tsinghua Science and Technology 2015年第2期20卷 200-204页

作者： Xin wen Xingwang Zhang Yaping zhu Faculty of Aerospace Engineering Shenyang Aerospace University College Astronautics Nanjing University of Aeronautics and Astronautics College Astronautics Nanjing University of Aeronautics and Astronautics

In this paper, we propose the Hyper Basis Function （HBF） neural network on the basis of Radial Basis Function （RBF） neural network. Compared with RBF, HBF neural networks have a more generalized ability with different activation functions. A decision tree algorithm is used to determine the network center. Subsequently, we design an adaptive observer based on HBF neural networks and propose a fault detection and diagnosis method based on the observer for the nonlinear modeling ability of the neural network. Finally, we apply this method to nonlinear systems. The sensitivity and stability of the observer for the failure of the nonlinear systems are proved by simulation, which is beneficial for real-time online fault detection and diagnosis.

关键词： observer fault detection hyper basis function neural networks

Consumer confidence and consumers’ preferences for infant formulas in China

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Journal of Integrative Agriculture 2019年第8期18卷 1793-1803页

作者： LI sai-wei zhu Chen CHEN Qi-hui LIU Yu-mei College of Economics and Management China Agricultural University Beijing 100083 P.R.China Center for Food and Health Economic Research College of Economics and Management China Agricultural University Beijing100083 P.R.China

A series of safety incidents related to domestically-produced infant formulas(DIFs) almost destroyed Chinese consumer confidence in domestic dairy products. Understanding consumer confidence and its effect on consumption behavior is important to restore consumer confidence and enhance the competitiveness of domestic dairy industry. This article first measures Chinese consumer confidence in DIFs safety using a two-dimension scale(optimism and pessimism) and then investigates its effect on consumers’ preferences for DIFs through a choice experiment. Involving 450 consumers residing in Beijing, Tianjin and Shijiazhuang, the experiment elicited information on their preferences for DIFs with six attributes(organic raw milk, farm-to-table traceability, region of origin, quality certification, animal welfare, and price). Our analysis yields four findings. First, Chinese consumers still lack confidence in DIFs safety. Second, quality certification is the most preferred product characteristic, followed by organic raw milk and farm-to-table traceability. Third, serving as a signal of high quality, price exerts a positive impact on choices of DIFs for pessimistic consumers. Finally, consumer preferences for farm-to-table traceability and region of origin are significantly influenced by consumer confidence.

关键词： consumer confidence food safety infant formula choice experiment willingness to pay China