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A CLASS Of fACTORIZED QUASI-NEWTON METHODS fOR NONLINEAR LEAST SQUARES PROBLEMS

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Journal of Computational mathematics 1996年第2期14卷 143-158页

作者： C.x. xu x.f. ma M.Y. Kong(Department of mathematics, xi’an Jiaotong University, xi’an, China) 西安交通大学数学系陕西西安

This paper gives a class of descent methods for nonlinear least squares solution. A class of updating formulae is obtained by using generalized inverse matrices. These formulae generate an approximation to the second part of the Hessian matrix of the objective function, and are updated in such a way that the resulting approximation to the whole Hessian matrix is the convex class of Broyden-like up-dating formulae. It is proved that the proposed updating formulae are invariant under linear transformation and that the class of factorized quasi-Newton methods are locally and superlinearly convergent. Numerical results are presented and show that the proposed methods are promising.

关键词： BfGS A CLASS Of fACTORIZED QUASI-NEWTON METHODS fOR NONLINEAR LEAST SQUARES PROBLEMS

mafHEmafICAL MODEL fOR MELTING PROCESSES Of SOLID ARTICLES IMMERSED IN METAL BATHS

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Acta Metallurgica Sinica(English Letters) 1999年第3期12卷 259-266页

作者： B.K. Li x.f. ma x.R. Zhang and J.C. He (Northeastern University, Shenyang 110006, China)(Northeastern University, Shenyang 110006, China)(Northeastern University, Shenyang 110006, China)(Northeastern University, Shenyang 110006, China) Northeastern University Shengyang China

A mathematical model for melting processes of solid particles immersed in metal baths has been develOPed, which includes the cases with the melting point of solid particles greater than, equal to, and lower than freezing point of the bath. Experiments are performed on the melting of ice spheres in water at different temperature. The model is validated by experimental data for melting of ice spheres submerged in water and aluminum spheres immersed in aluminum melt. finally, the parometers affecting particles melting time such as particle size, bath temperature, and slip velocity are analyzed.

关键词： mathematical model phase change solid particle

Ka-band thin film lithium niobate photonic integrated optoelectronic oscillator

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Photonics Research 2024年第6期12卷 1283-1293页

作者： RUI ma ZIJUN HUANG SHENGQIAN GAO JINGYI WANG xICHEN WANG xIAN ZHANG PENG HAO x.STEVE YAO xINLUN CAI State Key Laboratory of Optoelectronic materials and Technologies School of Electronics and Information TechnologySun Yat-sen UniversityGuangzhou 510275China Photonics Information Innovation Center and Hebei Provincial Center for Optical Sensing College of Physics Science and TechnologyHebei UniversityBaoding 071002China NuVison Photonics Inc.Las VegasNevada 89109USA

Photonics integration of an optoelectronic oscillator(OEO)on a chip is attractive for fabricating low cost,compact,low power consumption,and highly reliable microwave sources,which has been demonstrated recently in silicon on insulator(SOI)and indium phosphide(InP)platforms at x-band around 8 *** we demonstrate the first integration of OEOs on the thin film lithium niobate(TfLN)platform,which has the advantages of lower Vπ,no chirp,wider frequency range,and less sensitivity to *** have successfully realized two different OEOs operating at Ka-band,with phase noises even lower than those of the x-band OEOs on SOI and InP *** is a fixed frequency OEO at 30 GHz realized by integrating a mach–Zehnder modulator(MZM)with an add-drop microring resonator(MRR),and the other is a tunable frequency OEO at 20–35 GHz realized by integrating a phase modulator(PM)with a notch *** work marks the first step of using TfLN to fabricate integrated OEOs with high frequency,small size,low cost,wide range tunability,and potentially low phase noise.

关键词： optoelectronic modulator resonator

Supported Recyclable Metal-free frustrated Lewis Pair Catalyst for Catalytic Hydrogenation of Substituted Pyridines to Piperidines

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Chemical Research in Chinese Universities 2024年第4期40卷 682-689页

作者： ma Shaohua TANG Zhiyong CAS Key Laboratory for Nanosystem and Hierarchical fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing100190P.R.China University of Chinese Academy of Sciences Beijing100049P.R.China

The construction of heterogeneous frustrated Lewis pairs(fLPs)catalysts is crucial for realizing highly efficient and recyclable pyridines catalytic *** this work,we prepared a recyclable heterogenous fLPs catalyst CMP-Bf with conjugated microporous polymer CMP-ethynyl as the support via self-catalyzed 1,1-carboboration reaction with commercial Lewis acid B(C_(6)f_(5))_(3).The as-synthesized CMP-Bf demonstrates superior heterogenous catalytic hydrogenation performance(conversion>99%),and considerable stability(84%conversion after three cycles)in recyclable hydrogenation of 2,*** work provides insights into the fabrication and catalytic application of recyclable heterogenous fLP catalysts.

关键词： Pyridine hydrogenation frustrated Lewis pair Conjugated microporous polymer

Bioinspired nanomaterials for the treatment of bacterial infections

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Nano Research 2024年第2期17卷 691-714页

作者： xiaojing ma Wenjing Tang Rong Yang Robert f.Smith School of Chemical&Biomolecular Engineering Cornell UniversityIthacaNY 14853USA

Infectious diseases pose a serious threat to global *** immunizations can control most viral infections,bacterial infections,particularly those caused by drug-resistant strains,continue to cause high rates of illness and ***,the creation of new antibiotics has come to a grinding halt in the last ten *** response to this crisis,nanotechnology has emerged as a hopeful solution to tackle drug resistance and enhance treatment results.A large variety of biomimetic nanomaterials,termed nanozymes,have demonstrated strong antimicrobial *** the inherent toxicity of nanomaterials is a concern,recent studies have harnessed the stimuli-responsiveness of nanomaterials to enable local and/or targeted delivery to reduce the treatment side ***,the physicochemical versatility of nanomaterials affords many degrees of freedom that enable rational design of smart or autonomous therapeutics,which cannot be achieved using conventional *** design straddles the fields of catalysis,nanoscience,microbiology,and translational *** provide an overview of this interdisciplinary landscape,this review is organized based on composition into lipid,metal,metal oxide,and non-metallic *** as a delivery vehicle enhance bioavailability and reduce ***-and metal oxide-based nanomaterials inhibit bacterial growth by mimicking natural enzymatic activities such as peroxidase(POD)and ***,carbon-,polymer-,and cell membrane-based nanomaterials are combined into a discussion on non-metallic *** the end of this review,potentially fruitful directions for future bioinspired nanomaterials in infectious disease treatment are included.

关键词： bioinspired nanomaterial bacteria infectious disease antimicrobial liposome nanozyme

Partial regularity and nonlinear potential estimates for Stokes systems with super-quadratic growth

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Science China mathematics 2024年第7期67卷 1525-1554页

作者： Lingwei ma Zhenqiu Zhang School of mathematical Sciences Tianjin Normal UniversityTianjin300387China School of mathematical Sciences and LPMC Nankai UniversityTianjin300071China

This paper builds a bridge between partial regularity theory and nonlinear potential theory for the following generalized stationary Stokes system with super-quadratic growth and continuous coefficients:-div A(x,Du)+■π=f,div u=0,where Du is the symmetric part of the gradient■*** first establish anε-regularity criterion involving both the excess functional of the symmetric gradient Du and Wolff potentials of the nonhomogeneous term f to guarantee the local vanishing mean oscillation(VMO)-regularity of Du in an open subset Ω_(u) of Ω with full *** anε-regularity criterion leads to a pointwise Wolff potential estimate of Du,which immediately infers that Du is partially C^(0)-regular under appropriate ***,we give a local continuous modulus estimate of Du.

关键词： nonlinear Stokes system partial regularity Wolff potential estimates continuous modulus estimates

Lifetime-tunable circularly polarized luminescent system based on triplet-to-singlet förster resonance energy transfer

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Science China Chemistry 2024年第9期67卷 2918-2922页

作者： Zhenyi He Zizhao Huang xiang ma Key Laboratory for Advanced materials and feringa Nobel Prize Scientist Joint Research Center Institute of Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Circularly polarized luminescence(CPL)materials have received widespread attention due to their remarkable performance and broad ***,current CPL material research primarily focuses on tunable color,intensity,and *** CPL with adjustable lifetime remains a significant ***,a series of CPL polymeric materials with tunable lifetime were obtained by employing phosphorescent terephthalic acid and chiral organic small molecule R/S-BNAf(a luminescent binaphthol derivative)to copolymerize with acrylamide in different *** was verified that this performance results from the different energy transfer efficiency between luminophores with varying ratios of the monomers for *** strategy to realize CPL with tunable lifetime by modulating the energy transfer efficiency will provide a new perspective to broaden the applications of CPL materials.

关键词： circularly polarized luminescence tunable lifetime förster resonance energy transfer room temperature phosphorescence

Self-attention Guidance Based Crowd Localization and Counting

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machine Intelligence Research 2024年第5期21卷 966-982页

作者： Zhouzhou ma Guanghua Gu Wenrui Zhao School of Information Science and Engineering Yanshan UniversityQinhuangdao066000China Hebei Key Laboratory of Information Transmission and Signal Processing Qinhuangdao066000China

Most existing studies on crowd analysis are limited to the level of counting,which cannot provide the exact location of *** paper proposes a self-attention guidance based crowd localization and counting network(SA-CLCN),which can simultaneously locate and count *** take the form of object detection,using the original point annotations of crowd datasets as supervision to train the ***,the center point coordinate of each head as well as the number of crowds are ***,to cope with the spatial and positional variations of the crowd,the proposed method introduces transformer to construct a globallocal feature extractor(GLfE)together with the convolutional *** establishes the near-to-far dependency between elements so that the global context and local detail features of the crowd image can be extracted ***,this paper designs a pyramid feature fusion module(PffM)to fuse the global and local information from high level to low level to obtain a multiscale feature *** downstream tasks,this paper predicts candidate point offsets and confidence scores by a simple regression header and classification *** addition,the Hungarian algorithm is used to match the predicted point set and the labelled point set to facilitate the calculation of *** proposed network avoids the errors or higher costs associated with using traditional density maps or bounding box ***,we have conducted extensive experiments on several crowd datasets,and the proposed method has produced competitive results in both counting and localization.

关键词： Crowd localization crowd counting transformer point supervision object detection

Genetic characteristics of H1N1 influenza virus outbreak in China in early 2023

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Virologica Sinica 2024年第3期39卷 520-523页

作者： xuanxuan Li Zefeng Dong Jiaming Li Chuanran Dou Deyu Tian Zhenghai ma Wenjun Liu George f.Gao Yuhai Bi College of Life Science and Technology Xinjiang UniversityUrumchi830046China CAS Key Laboratory of Pathogen Microbiology and Immunology Institute of MicrobiologyCenter for Influenza Research and Early-warning(CASCIRE)CAS-TWAS Center of Excellence for Emerging Infectious Diseases(CEEID)Chinese Academy of SciencesBeijing100101China Suzhou Center for Disease Control and Prevention Suzhou215004China Lafayette College EastonPA 18042USA University of Chinese Academy of Sciences Beijing100049China D.H.Chen School of Universal Health Zhejiang UniversityHangzhou 310058China

Dear Editor,Influenza A virus(IAV)exhibits rapid mutability and antigenic *** the 20th century,IAV has caused at least four pandemics(Yang et al.,2022).Presently,seasonal H_(3)N_(2)and H1N1 are the prevailing human-adaptive IAV subvariants responsible for human *** implementation of public health interventions since the commencement of the COVID-19 pandemic has effectively curtailed global influenza circulation(Olsen et al.,2021).following the downregulation of the prevention and control strategies against COVID-19,global influenza activity is showing a recovery.

关键词： influenza prevention H1N1