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Hubbard model on an anisotropic checkerboard lattice at finite temperatures: Magnetic and metal–insulator transitions

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Chinese Physics B 2019年第10期28卷 498-503页

作者： hai-Di liu State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of Sciences

We study magnetic and Mott transitions of the Hubbard model on the geometrically frustrated anisotropic checkerboard lattice at half filling using cellular dynamical mean-field theory. Phase diagrams over a wide area of the parameter space are obtained by varying the interparticle interaction strength, geometric frustration strength, and temperature. Our results show that frustration and thermal fluctuations play a competing role against the interactions and in general favor a metallic phase without antiferromagnetic order. Due to their interplay, the system exhibits competition between antiferromagnetic insulator, antiferromagnetic metal, paramagnetic insulator, and paramagnetic metal phases in the intermediateinteraction regime. In the strong-interaction limit, which reduces to the Heisenberg model, our result is consistent with previous studies.

关键词： geometrical frustration checkerboard lattice Hubbard model

The Boundedness of Maximal Operators and Singular Integrals via Fourier Transform Estimates

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Acta Mathematica Sinica,English Series 2012年第11期28卷 2227-2242页

作者： Hong hai liu School of Mathematics and Information Science He'nan Polytechnic University

In this paper, the author studies the mapping properties for some general maximal op- erators and singular integrals on certain function spaces via Fourier transform estimates. Also, some concrete maximal operators an... 详细信息

关键词： Maximal operators singular integrals Triebel-Lizorkin spaces vector-valued inequality

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Acta Mathematica Sinica,English Series 2017年第7期33卷 1011-1020页

作者： Hong hai liu School of Mathematics and information Science He'nan Polytechnic UniversityJiaozuo 454003P.R.China

Abstract In this paper, we give counterexamples to show that variation and oscillation operators related to rough truncations of the Hilbert transform are not bounded from H1 to L1, and prove variation, oscillation an... 详细信息

关键词： Variation operator oscillation operator A-jump operator the Hilbert transform Hardyspace

On Discreteness of the Hopf Equation

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Acta Mathematicae Applicatae Sinica 2008年第3期24卷 423-440页

作者： hai-liang liu Iowa State University USA

The principle aim of this essay is to illustrate how different phenomena is captured by different discretizations of the Hopf equation and general hyperbolic conservation laws. This includes dispersive schemes, shock capturing schemes as well as schemes for computing multi-valued solutions of the underlying equation. We introduce some model equations which describe the behavior of the discrete equation more accurate than the original equation. These model equations can either be conveniently discretized for producing novel numerical schemes or further analyzed to enrich the theory of nonlinear partial differential equations.

关键词： Hopf equation dispersive scheme shock capturing schemes multi-valued solutions level set equation

Holomorphic Deformations of the Ricci-flat ?-manifolds

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Acta Mathematica Sinica,English Series 2016年第6期32卷 643-658页

作者： hai Sheng liu Center of Mathematical Sciences Zhejiang University Hangzhou 310027 P. R. China

We present a construction of globally convergent power series of integrable Beltrami differentials on the Ricci-flat -manifolds and also a construction of global canonical family of holomorphic （n, 0）-forms on the... 详细信息

关键词： Deformations of complex structures Ricci-flat -manifold

Artemisinin, GABA signaling and cell reprogramming： when an old drug meets modern medicine

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Science Bulletin 2017年第6期62卷 386-387页

作者： hai-Kun liu Division of Molecular Neurogenetics German Cancer Research Center (DI(FZ) DKFZ-ZMBH Alliance Heidelberg 69120 Germany

The hormone-secreting endocrine cells(α,β,δ,ε and PP cells)form pancreatic islets,which are strongly involved in regulation of *** of insulin-producingβcells is the major cause of type 1 *** progress in cell reprogramming demonstrates the feasibility of generating functionalβcells to treat type 1 diabetes[1].However,a non-invasive in vivo approach forβcell reprogramming is still ***,two reports in

关键词： GABA cell Artemisinin,GABA signaling and cell reprogramming:when an old drug meets modern medicine

A federated learning scheme meets dynamic differential privacy

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CAAI Transactions on Intelligence Technology 2023年第3期8卷 1087-1100页

作者： Shengnan Guo Xibin Wang Shigong Long hai liu liu hai Toong hai Sam State Key Laboratory of Public Big Data College of Computer Science and TechnologyGuizhou UniversityGuiyangChina School of Big Data Key Laboratory of Electric Power Big Data of Guizhou ProvinceGuizhou Institute of TechnologyGuiyangChina School of Information Guizhou University of Finance and EconomicsGuiyangChina Faculty of Business and Communication INTI International UniversityNilaiMalaysia

Federated learning is a widely used distributed learning approach in recent years,however,despite model training from collecting data become to gathering parameters,privacy violations may occur when publishing and sharing models.A dynamic approach is pro-posed to add Gaussian noise more effectively and apply differential privacy to federal deep ***,it is abandoning the traditional way of equally distributing the privacy budget e and adjusting the privacy budget to accommodate gradient descent federation learning dynamically,where the parameters depend on computation derived to avoid the impact on the algorithm that hyperparameters are created *** also incorporates adaptive threshold cropping to control the sensitivity,and finally,moments accountant is used to counting the∈consumed on the privacy‐preserving,and learning is stopped only if the∈_(total)by clients setting is reached,this allows the privacy budget to be adequately explored for model *** experimental results on real datasets show that the method training has almost the same effect as the model learning of non‐privacy,which is significantly better than the differential privacy method used by TensorFlow.

关键词： data privacy machine learning security of data

Ground states of a nonlinear Schrodinger system with nonconstant potentials

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Science China Mathematics 2015年第2期58卷 257-278页

作者： liu hai Dong liu Zhao Li College of Mathematics Physics and Information Engineering Jiaxing University School of Mathematical Sciences Capital Normal University

In the case where either the potentials Vj,μj andβare periodic or Vj are well-shaped andμj andβare anti-well-shaped,existence of a positive ground state of the Schrdinger system -Δu1+V1(x)u1=μ1(x)u31+β(x)u1u22in RN,-Δu2+V2(x)u2=β(x)u21u2+μ2(x)u32in RN,uj∈H1(RN),j=1,2,where N=1,2,3,is proved provided thatβis either small or large in terms of Vj andμ*** system with constant coefficients has been studied extensively in the last ten years,and the nonconstant coefficients case has seldom been *** turns out that new technical machineries in the setting of variational methods are needed in dealing with the nonconstant coefficients case.

关键词：薛定谔非恒定系统非线性基态变分方法 U31 常系数

Analysis of the 3' ends of tRNA as the cause of insertion sites of foreign DNA in Prochlorococcus

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第9期11卷 708-718页

作者： hai-lan liu Jun ZHU Institute of Bioinformaties College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China Institute of Maize Research College of Agriculture Sichuan Agricultural University Ya'an 625014 China

The purpose of this study was to investigate the characteristics of transfer RNA(tRNA) responsible for the association between tRNA genes and genes of apparently foreign origin(genomic islands) in five high-light adapted Prochlorococcus *** bidirectional best BLASTP(basic local alignment search tool for proteins) search and the conservation of gene order against each other were utilized to identify genomic islands,and 7 genomic islands were found to be immediately adjacent to tRNAs in Prochlorococcus marinus AS9601,11 in *** MIT9515,8 in *** MED4,6 in *** MIT9301,and 6 in *** *** Carlo simulation showed that tRNA genes are hotspots for the integration of genomic islands in Prochlorococcus *** tRNA genes associated with genomic islands showed the following characteristics:(1) the association was biased towards a specific subset of all iso-accepting tRNA genes;(2) the codon usages of genes within genomic islands appear to be unrelated to the codons recognized by associated tRNAs;and,(3) the majority of the 3' ends of associated tRNAs lack CCA *** findings contradict previous hypotheses concerning the molecular basis for the frequent use of tRNA as the insertion site for foreign genetic *** analysis of a genomic island associated with a tRNA-Asn gene in *** MIT9301 suggests that foreign genetic material is inserted into the host genomes by means of site-specific recombination,with the 3' end of the tRNA as the target,and during the process,a direct repeat of the 3' end sequence of a boundary tRNA(namely,a scar from the process of insertion) is formed elsewhere in the genomic *** the analysis of the sequences of these targets,it can be concluded that a region characterized by both high GC content and a palindromic structure is the preferred insertion site.

关键词： Genomic islands Prochlorococcus Transfer RNA(tRNA) Palindromic structure Codon usage