检索结果-南通市图书馆

Wideband Millimeter Wave Antenna with Cavity Backed Slotted Patch and Magneto-Electric Dipole

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2024年第5期33卷 1234-1244页

作者： Yang cheng Yuandan DONG School of Electronic Science and Engineering University of Electronic Science and Technology of China

This paper proposes a wideband cavity-backed slotted patch antenna, loaded with a magneto-electric（ME）-dipole and fed by a microstrip line, for millimeter wave（mm-Wave） applications. The coupled-feed cavitybacked slotted patch antenna is loaded with the ME-dipole. The slotted patch antenna serves as both a radiator and a ground for the ME-dipole. The combination of the ME-dipole antenna and the slotted patch antenna realizes a –10 dB impedance bandwidth covering over 22.86–44.35 GHz（63.9%）. The pattern of the antenna element remains stable throughout this bandwidth. The proposed broadband antenna unit not only realizes single linearly polarized（LP）radiation but also can be designed for dual-LP radiation. The dual-polarized radiation can be achieved by changing the slot of the patch antenna to a crossed slot and altering the ME-dipole antenna to a dual-polarization form. A 2 × 2 dual-polarized array has been designed, fabricated, and tested. A novel dual-polarized feeding network is *** achieve higher isolation, broadband in-phase feed and differential feed are adopted, respectively. A low-loss single to the differential structure is proposed for differential feeding. The simulated isolation of the array is higher than 40 d *** results show that the dual-polarized 2 × 2 array has an overlapping bandwidth of 52.3%(|S11| < –10 dB and |S21| < –30 dB) with a peak gain of 14 dBi. The proposed antenna, featuring a wide overall bandwidth, low cost,and good radiation performance, is well suited for mm-Wave applications.

关键词： Slot antennas Costs Dipole antennas Patch antennas Magnetoelectric effects Broadband communication Broadband antennas Array antenna Dual-polarized antenna Feeding network Magneto-electric dipole Millimeter-wave (mm-Wave) Patch BROAD-BAND POLARIZED ANTENNA ARRAY PLANAR BALUN

Cohomology groups of a new class of Kadison-Singer algebras

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Mathematics 2024年第3期67卷 593-606页

作者： Guangyu An Xing cheng Jun Sheng School of Mathematics and Data Science Shaanxi University of Science and TechnologyXi’an 710021China

Let N be a maximal discrete nest on an infinite-dimensional separable Hilbert space H,ξ=∑^(∞)_(n=1)en/2n be a separating vector for the commutant N',E_(ξ)be the projection from H onto the subspace[Cξ]spanned by the vectorξ,and Q be the projection from K=H⊕H⊕H onto the closed subspace{(η,η,η)^(T):η∈H}.Suppose that L is the projection lattice generated by the projections(E_(ξ) 0 0 0 0 0 0 0 0),{(E 0 0 0 0 0 0 0 0):E∈N},(I 0 0 0 I 0 0 0 0) and *** show that L is a Kadison-Singer lattice with the trivial ***,we prove that every n-th bounded cohomology group H~n(AlgL,B(K))with coefficients in B(K)is trivial for n≥1.

关键词： Kadison-Singer algebra Kadison-Singer lattice derivation cohomology group

Rational Schur Superalgebras

在线全文

学校读者我要写书评

暂无评论

Algebra Colloquium 2024年第2期31卷 209-220页

作者： Andrew Riesen Shun-Jen cheng Department of Mathematical and Statistical Sciences University of Alberta 1132489 Ave NWEdmontonAlbertaCanada 不详

We develop and study the generalization of rational Schur algebras to the super *** to the classical case,this provides a new method for studying rational supermodules of the general linear supergroup GL(m|n).Furthermore,we establish a Schur-Weyl duality result for rational Schur superalgebras and conclude that under certain conditions these objects will be semisimple.

关键词： Schur algebra supermathematics general linear supergroup

Elastic wave insulation and propagation control based on the programmable curved-beam periodic structure

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第10期45卷 1791-1806页

作者： Jiajia MAO Hong cheng Tianxue MA Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures Department of MechanicsSchool of MathematicsStatistics and MechanicsBeijing University of TechnologyBeijing 100124China Department of Mechanics School of Physical Science and EngineeringBeijing Jiaotong UniversityBeijing 100044China

Curved-beams can be used to design modular multistable metamaterials(MMMs)with reprogrammable material properties,i.e.,programmable curved-beam periodic structure(PCBPS),which is promising for controlling the elastic wave *** PCBPS is theoretically equivalent to a spring-oscillator system to investigate the mechanism of bandgap,analyze the wave propagation mechanisms,and further form its geometrical and physical criteria for tuning the elastic wave *** the equivalent model,we calculate the analytical solutions of the dispersion relations to demonstrate its adjustability,and investigate the wave propagation characteristics through the *** validate the equivalent system,the finite element method(FEM)is *** is revealed that the bandgaps of the PCBPS can be turned on-and-off and shifted by varying its physical and geometrical *** findings are highly promising for advancing the practical application of periodic structures in wave insulation and propagation control.

关键词： curved-beam based periodic structure equivalent stiffness spring-oscillator system dispersion relation wave propagation

Construction of conservation laws for the Gardner equation,Landau-Ginzburg-Higgs equation,and Hirota-Satsuma equation

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2024年第5期76卷 49-57页

作者： cheng Chen Faiza Afzal Yufeng Zhang School of Mathematics China University of Mining and TechnologyXuzhou221116China Jiangsu Center for Applied Mathematics(CUMT) XuzhouJiangsu 221116China

In this paper,two different methods for calculating the conservation laws are used,these are the direct construction of conservation laws and the conservation theorem proposed by *** these two methods,we obtain the co... 详细信息

关键词： conservation laws Landau-Ginzburg-Higgs equation Hirota-Satsuma equation Gardner equation

Ternary superhydrides for high-temperature superconductivity at low pressures

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第7期11卷 12-14页

作者： Pengfei Shan Liang Ma Jinguang cheng Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences School of Physical Sciences University of Chinese Academy of Sciences Key Laboratory of Materials Physics Ministry of Education School of Physics and Microelectronics Zhengzhou University

The quest for room-temperature superconductivity(RTSC) has been a longstanding pursuit in physics since the discovery of superconductivity in *** to the conventional Bardeen-Cooper-Schrieffer theory, atomic metallic hydrogen holds great promise for achieving this goal due to its high Debye temperature and strong electron-phonon coupling.

关键词：

Friction Characteristics Between Marine Clay and Construction Materials

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2024年第2期23卷 427-437页

作者： KOU Hailei HUANG Jiaming cheng Yang College of Engineering Ocean University of ChinaQingdao 266100China Fourth Division Organization Department of the CPC Qingdao Municipal CommitteeQingdao 266100China

Structure-soil interface friction characteristics is of importance to investigate the interaction between engineering structures and soils,especially for offshore *** interface friction behavior between marine clay and structural materials with different roughness was studied in this paper by using 3D optical scanning tests,a modified direct shear device and numerical *** between the surface roughness of structures,water content and interface friction angle were presented by model *** increase of water contents decreased the interface friction *** interfaces with different roughness,the interface friction angles will be smaller than that of the soil when the water content exceeds a certain *** roughness of the interface and the water content of the soil are mutually coupled to influence the coefficient of friction(COF).This paper proposed a Finite Element Method(FEM)to simulate the interface direct shear tests of structures with different *** surface models with different roughness are established based on the structure data obtained by 3D *** Coupled Eulerian-Lagrangian(CEL)approach was employed to analyse soils sheared by irregular *** interface behavior for interfaces with different roughness under cyclic shear stresses was analyzed by FEM.

关键词： marine clay construction material interface friction behavior surface roughness Finite Element Method

Continuous Orbit Equivalence of Semigroup Actions

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第6期40卷 1581-1598页

作者： Xiang Qi QIANG cheng Jun HOU School of Mathematical Science Yangzhou UniversityYangzhou 225002P.R.China

We introduce notions of continuous orbit equivalence and its one-sided version for countable left Ore semigroup actions on compact spaces by surjective local homeomorphisms,and characterize them in terms of the corresponding transformation groupoids and their operator *** particular,we show that two essentially free semigroup actions on totally disconnected compact spaces are continuously orbit equivalent if and only if there is a canonical abelian subalgebra preserving C^(∗)-isomorphism between the associated transformation groupoid C^(∗)-*** also give some examples of orbit equivalence,consider the special case of semigroup actions by homeomorphisms and relate continuous orbit equivalence of semigroup actions to that of the associated group actions.

关键词： Semigroup action continuous one-sided orbit equivalence continuous orbit equivalence groupoid C^(∗)-algebras

On the global smooth solutions of 3D incompressible Hall-MHD equations

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 319-327页

作者： YUE Gao-cheng SUN Wen-da School of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211106China

The present paper is devoted to the well-posedness issue for the 3D incompressible Hall-MHD system obtained from kinetic models. Our analysis strongly relies on the use of the Fourier analysis. We establish the global existence of smooth solutions for a class of large initial data, this result implies the initial velocity and magnetic field can be arbitrarily large.

关键词： 3D Hall-MHD well-posedness Fourier analysis