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Extending Structures f.r Gel'f.nd-Dorf.an Bialgebras

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Acta Mathematica Sinica,English Series 2024年第2期40卷 619-638页

作者： jia jia WEN Yan Yong HONG School of.Mathematics Hangzhou Normal UniversityHangzhou 311121P.R.China

Gel'f.nd-Dorf.an bialgebra,which is both a Lie algebra and a Novikov algebra with some compatibility condition,appeared in the study of.Hamiltonian pairs in completely integrable *** also emerged in the description of.a class special Lie conf.rmal algebras called quadratic Lie conf.rmal *** this paper,we investigate the extending structures problem f.r Gel'f.nd-Dorf.an bialgebras,which is equivalent to some extending structures problem of.quadratic Lie conf.rmal ***,given a Gel'f.nd-Dorf.an bialgebra(A,o,[.,.]),this problem is how to describe and classif. all Gel'f.nd-Dorf.an bialgebra structures on a vector space E(A⊂E)such that(A,o,[.,.])is a subalgebra of.E up to an isomorphism whose restriction on A is the identity *** by the theories of.extending structures f.r Lie algebras and Novikov algebras,we construct an object gH2(V,A)to answer the extending structures problem by introducing the notion of.a unif.ed product f.r Gel'f.nd-Dorf.an bialgebras,where V is a complement of.A in *** particular,we investigate the special case when dim(V)=1 in detail.

关键词： Gel'f.nd-Dorf.an bialgebra Lie conf.rmal algebra Extending structures problem Novikovalgebra

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f.cile synthesis of.transition metal complexes with f.ve coplanar metal-carbon σ-bonds

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National Science Review 2024年第4期11卷 11-12页

作者： Guocheng jia Department of.Chemistry Hong Kong University of Science and Technology

Carbon is one of.the most important elements in chemistry, f.rming a vast number of.organic compounds. It can also f.rm a variety of.organometallic compounds with a metal–carbon bond. Metal alkyl, carbene and carbyne complexes are classical examples of.organometallic compounds. A particularly interesting class of.organometallic compounds are all-carbon metallacycles f.rmed by combination of.a metal and a hydrocarbon chain serving as a chelating agent with only carbon atoms as the donor atoms. Many interesting monocyclic metallacycles made of.a chelating bidentate hydrocarbon chain are known, f.r example, metallacyclobutadienes, metallacyclopentadienes and metallabenzenes[1].

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Geometric Constraints f.r Global Regularity of.3D Shear Thickening f.uids

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 205-210页

作者： jia-qi Yang Research&Development Institute of.Northwestern Polytechnical University in Shenzhen Shenzhen518063China Key Laboratory f.r Mechanics in f.uid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing100190China

We consider the relation between the direction of.the vorticity and the global regularity of.3D shear thickening *** is showed that a weak solution to the non-Newtonian incompressible f.uid in the whole space is stron... 详细信息

关键词： direction of.the vorticity non-Newtonian f.uid global regularity

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Two-dimensional ballistic transistors f.r advanced-node integrated circuits

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National Science Review 2024年第3期11卷 9-10页

作者： jia Li Xidong Duan Hunan Provincial Key Laboratory of.Two-Dimensional Materials State Key Laboratory for Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University

As the f.ature size of.metal-oxide-semiconductor-f.eld-ef.ect-transistors(MOSf.Ts) in integrated circuits(ICs)is reduced to sub-10-nm, the traditional channel materials are plagued by enhanced scattering and short-cha... 详细信息

关键词： CONTACT

Numerical analysis of.the correlation between f.uid dynamic modes and hydrodynamic noise in f.ows around a three-dimensional circular cylinder

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Journal of.Hydrodynamics 2024年第1期36卷 119-129页

作者： jia-jia Qin Ming-xin Zou Yuan Zhuang De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Wuhan Second Ship Design and Research Institute Wuhan430205China

The f.ow around a circular cylinder f.r Re=1000 is characterized by f.ow separation and Karman vortex *** typical f.ow f.atures can be captured to study the correlation between f.uid f.elds and sound *** this paper,the three-dimensional circular cylinder is taken as the research object,and the probes of.surf.ce f.uctuating pressure and f.r f.eld sound pressure are arranged every 10°.The directional diagram and the coherence of.f.uctuating pressure and sound pressure are *** relationship between the f.ow mode and hydrodynamic noise is studied by using dynamic mode decomposition(DMD).The characteristics of.the dipole and quadrupole sound source term of.a long span cylinder are *** results show that at the angles between 30°–120°and 190°–350°,the f.uctuating pressure contributes more to the generation of.dipole *** quadrupole sound source shows three-dimensional ef.ects,which is more obvious in a cylinder with large spanwise length.

关键词： Pressure coherence dynamic mode decomposition f.ow-sound correlation circular cylinder

Enhance the Perf.rmance of.Directional f.ature-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 Inf.rmation 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 f.atures 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 f.ature. We then propose a novel palmprint directional response stability measurement (DRSM) to judge the stability of.the directional f.ature of.each pixel. Af.er f.ltering the palmprint image with the f.lter bank, we design DRSM according to the relationship between the maximum response value and other response values f.r each pixel. Using DRSM, we can judge those pixels with unstable directional response and use a specially designed encoding mode related to a specif.c method. We insert the DRSM mechanism into seven classical methods based on directional f.ature, and conduct many experiments on six public palmprint databases. The experimental results show that the DRSM mechanism can ef.ectively improve the perf.rmance of.these methods. In the f.eld of.palmprint recognition, this work is the f.rst in-depth study on the stability of.the palmprint directional response, so this paper has strong ref.rence value f.r research on palmprint recognition methods based on directional f.atures.

关键词： Biometrics palmprint recognition directional response stability directional coding-based methods directional f.ature

Structural engineered living materials

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Nano Research 2024年第2期17卷 715-733页

作者： Yang Geng Zian jia Ling Li 635 Prices f.rk Road Department of Mechanical EngineeringVirginia Polytechnic Institute and State UniversityBlacksburg VA24061USA

Biological structural materials not only exhibit remarkable mechanical properties but also of.en embody dynamic characteristics such as environmental responsiveness,autonomy,and self.healing,which are dif.icult to achieve in conventional engineering *** merging materials science,synthetic biology,and other disciplines,engineered living materials(ELMs)provide a promising solution to combine living organisms with abiotic components,thus f.cilitating the construction of.f.nctional“living”*** natural materials,ELMs possess vitality and hold immense application potential in areas such as medicine,electronics,and construction,captivating increasing research attention *** an emerging branch of.ELMs,structural ELMs aim to mimic living biological structural materials by achieving desired mechanical perf.rmance while maintaining important“living”*** we summarize the recent progress and provide our perspectives f.r this emerging research *** f.rst summarize the superiority of.structural ELMs by reviewing biological structural materials and biomimetic material design ***,we provide a systematic discussion on the def.nition and classif.cations of.structural ELMs,their mechanical perf.rmance,and physiological ***,we summarize some critical challenges f.ced by structural ELMs and highlight directions of.f.ture *** hope this review article can provide a timely summary of.the state of.the art and relevant perspectives f.r f.ture development of.structural ELMs.

关键词： structural materials engineered living materials(ELMs) structural ELMs composites mechanical properties

The Method of.Polynomial Particular Solutions f.r Solving Nonlinear Poisson-Type Equations

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Acta Mechanica Solida Sinica 2024年第1期37卷 155-165页

作者： Zhile jia Yanhua Cao Xiaoran Wu School of.Sciences East China Jiaotong UniversityNanchang 330013China

In this paper,the method of.polynomial particular solutions is used to solve nonlinear Poisson-type partial dif.erential equations in one,two,and three *** condition number of.the coef.icient matrix is reduced through the implementation of.multiple scale technique,ultimately yielding a stable numerical *** methodological process can be divided into two main parts:f.rst,identif.ing the corresponding polynomial particular solutions f.r the linear dif.erential operator terms in the governing equations,and second,employing these polynomial particular solutions as basis f.nction to iteratively solve the remaining nonlinear terms within the governing ***,we investigate the potential improvement in numerical accuracy f.r equations with singularities in the analytical solution by shif.ing the computational domain a certain *** experiments are conducted to assess both the accuracy and stability of.the proposed method.A comparison of.the obtained results with those produced by other numerical methods demonstrates the accuracy,stability,and ef.iciency of.the proposed method in handling nonlinear Poisson-type partial dif.erential equations.

关键词： Nonlinear equation Singularity Polynomial particular solutions Poisson type

Climatic impacts induced by winter wheat irrigation over North China simulated by the nonhydrostatic RegCM4.7

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Advances in Climate Change Research 2024年第2期15卷 197-210页

作者： jia WU Zhen-Yu HAN Xue-Jie GAO Zheng-jia LIU National Climate Centre China Meteorological AdministrationBeijing 100081China Key Laboratory f.r Climate Studies China Meteorological AdministrationBeijing 100081China Climate Change Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on f.recast and Evaluation of.Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China Institute of.Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

Quantif.cation of.the impact of.winter wheat irrigation on the climate and the occurrence of.extreme climatic events over North China is crucial f.r regional adaptation *** related studies mainly f.cused on the impact on surf.ce processes;however,f.w f.cused on the ef.ects of.extreme events using high-resolution nonhydrostatic regional climate ***,the 9-km-resolution nonhydrostatic RegCM4.7 was coupled with a crop irrigation scheme and an updated winter wheat irrigation dataset to better simulate irrigation *** experiments were conducted with and without winter wheat irrigation to isolate the ef.ects of.*** showed that irrigation simulation reduces the model biases in temperature,precipitation,latent heat f.ux,soil moisture,sensitive heat f.ux,and top-layer soil ***,it also reduces the bias and increases the correlation with observations obtained in irrigated areas,especially in summer,indicating better representation of.irrigation *** wheat irrigation tends to cause substantial cooling of.the local surf.ce maximum,minimum,and mean air temperatures(by-1.68,-0.34,and-0.79℃,respectively)over irrigated areas of.North China,with the largest changes observed in relation to maximum ***,precipitation is f.und to increase during spring and summer,which is strongly related to water vapor transport in the lower levels of.the *** analyses indicated that the number of.annual mean hot days decrease(-13.9 d),whereas the number of.both comf.rt days(+10.2 d)and rainy days(days with total precipitation greater than 1 mm:+6.6 d)increase over irrigated areas,demonstrating benef.cial f.edback to human perception and ***,although the heat wave risk increases(number of.annual mean heat wave days:+5.8 d),the impact is limited to small areas within irrigated ***,no notable change was f.und in terms of.heavy rainf.ll events and precipitation intensity

关键词： Nonhydrostatic regional climate model Irrigation ef.ect Extreme events North China