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compact Interlaced Dual Circularly Polarized Sequentially Rotated Dielectric-Resonator Antenna Array

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Computers, Materials & Continua 2022年第9期72卷 4631-4643页

作者： Yazeed Qasaymeh Department of Electrical Engineering College of EngineeringMajmaah UniversityAL-Majmaah11952Saudi Arabia

In this study,a compact 2×2 interlaced sequentially rotated dual-polarized dielectric-resonator antenna array is proposed for 5.8 GHz applications.The array is composed of a novel unit elements that are made of rectangular dielectric resonator(RDR)coupled to an eye slot for generating the orthogonal modes,TEδx 21 and TE1yδ1 to acquire circular polarization(CP)radiation.For the purpose of miniaturization and achieving dual polarized resonance,the array is fed by two interlaced ports and each port excites two radiating elements.The first port feeds horizontal elements to obtain left hand circular polarization(LHCP).The second port feeds vertical elements to obtain right hand circular polarization(RHCP).A quarter-wave length transformer is employed to reduce the attenuation and consequently increase the array gain performance.The 35×35 mm2(0.676λ0×0.676λ0)gains were 8.4 and 8.2 dBi for port 1 and port 2,respectively,with port isolations of−33.51 dB.The design achieves a voltage standing-wave ratio(VSWR)<−10 dB and an axial ratio(AR)<−3 dB bandwidth of 2.48%(5.766 to 5.911 GHz)for LHCP at port 1 and a VSWR<−10 dB and AR<−3 dB bandwidth of 2.28%(5.788 to 5.922 GHz)for RHCP at port 2.The findings of the proposed design validate its use for ISM band applications.

关键词： Antenna array compact dielectric resonator antenna dual polarized interlaced sequential rotation

Alternatingly stacked thin film electrodes-based compact aqueous hybrid electrochemical capacitors for hundred-volts AC line filtering

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Journal of Energy Chemistry 2023年第3期78卷 158-168,I0005页

作者： Lixia Wang Lingyu Zhao Meirong Song Lixia Xie Xiaopeng Wang Xin Li Yanjie Huang Min Wei Qiu Jin Xianglong Meng Yang Zhao College of Science Henan Agricultural UniversityZhengzhou 450002HenanChina Key Laboratory of Cluster Science Ministry of Education of ChinaBeijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

Filtering capacitor with compact configuration and a wide range of operating voltage has been attracting increasing attention for the smooth conversion of the electric signal in modern circuits.Lossless integration of capacitor units can be regarded as one of the efficient ways to achieve a wider voltage range,which has not yet been fully conquered due to the lack of rational designs of the electrode structure and integration technology.This study presents an alternatingly stacked assemble technology to conveniently fabricate compact aqueous hybrid integrated filtering capacitors on a large scale,in which a unit consists of rGO/MXene composite film as a negative electrode and PEDOT:PSS based film as a positive electrode.Benefiting from the synergistic effect of rGO and MXene components,and morphological characteristics of PEDOT:PSS,the capacitor unit exhibits outstanding AC line filtering with a large areal specific energy density of 1,015 μF V^(2)cm^(-2)(0.28 μW h cm^(-2)) at 120 Hz.After rational integration,the assembled capacitors present compact/lightweight configuration and lossless frequency response,as reflected by almost constant resistor-capacitor time constant of 0.2 ms and dissipation factor of 15% at120 Hz,identical to those of the single capacitor unit.Apart from standing alone steadily on a flower,a small volume(only 8.1 cm^(3)) of the integrated capacitor with 70 units connected in series achieves hundred-volts alternating current line filtering,which is superior to most reported filtering capacitors with sandwich configuration.This study provides insight into the fabrication and application of compact/ultralight filtering capacitors with lossless frequency response,and a wide range of operating voltage.

关键词： Alternatingly stacked assembly Lossless integration Aqueous hybrid electrochemical capacitor Synergistic effect Morphological characteristics compact Hundred-volts AC lineﬁltering

On Some Topological Properties of Normed Boolean Algebras

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Advances in Pure Mathematics 2024年第5期14卷 367-387页

作者： Vesna Gotovac Đogaš Faculty of Science University of Split Split Croatia

This paper concerns the compactness and separability properties of the normed Boolean algebras (N.B.A.) with respect to topology generated by a distance equal to the square root of a measure of symmetric difference between two elements. The motivation arises from studying random elements talking values in N.B.A. Those topological properties are important assumptions that enable us to avoid possible difficulties when generalising concepts of random variable convergence, the definition of conditional law and others. For each N.B.A., there exists a finite measure space ( E,ℰ,μ ) such that the N.B.A. is isomorphic to ( ℰ ˜ , μ ˜ ) resulting from the factorisation of initial σ-algebra by the ideal of negligible sets. We focus on topological properties ( ℰ ˜ , μ ˜ ) in general setting when μ can be an infinite measure. In case when μ is infinite, we also consider properties of ℰ ˜ fin ⊆ ℰ ˜ consisting of classes of measurable sets having finite measure. The compactness and separability of the N.B.A. are characterised using the newly defined terms of approximability and uniform approximability of the corresponding measure space. Finally, conditions on ( E,ℰ,μ ) are derived for separability and compactness of ℰ ˜ and ℰ ˜ fin .

关键词： compact Locally compact Polish Space Separable

Active,compact,wideband,receiving filtenna with power adaptation for space-limited wireless platforms

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Chinese Journal of Aeronautics 2022年第8期35卷 7-11页

作者： LI Daotong YU Yaqing TANG Ming-Chun LI Dajiang MU Dongmei LI Mei School of Microelectronics and Communication Engineering Chongqing UniversityChongqing 400044China Institute of Wireless Mobile Information Technology School of Electronic Engineering of Beijing UniversityPosts and TelecommunicationsBeijing 100876China

An active,compact,wideband,receiving filtenna with power adaptation for space-limited wireless platforms is presented.By organically combining a filtering antenna and a Variable Gain Amplifier(VGA),the proposed co-designed active filtenna is achieved.Its power adaptation is empowered by controlling gain of the VGA unit.A demonstrated prototype with a compact overall size is fabricated,assembled and measured.Good performances are achieved.Furthermore,in any condition,the proposed active filtenna displays outstanding impedance matching(|S_(11)|<−10 dB)and high passband skirt selectivity at upper and lower stopbands(Selectivity≥170 dB/GHz).

关键词： Amplifier compact Power adaptation VGA Wideband

compact Wavelength Demultiplexer Structure Based on Side-Coupled Cavities

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Chinese Physics Letters 2012年第10期29卷 73-76页

作者：陈召宋钢于丽陈建军肖井华 State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876 School of Science Beijing University of Posts and TelecommunicationsBeijing 100876

A novel structure based on a side-coupled cavity for optical wavelength demultiplexing is proposed and demonstrated numerically by using the two-dimensional finite element method.It is found that the transmission wavelength of each channel can be tuned by adjusting the geometrical parameters of the structure and the material filling the side-coupled cavity.Moreover,by introducing a reflection nanocavity,the value of the transmitted-peak can be improved significantly.The results of theoretical analysis and simulation are well consistent with each other.

关键词： cavity structure compact

compact representations of microstructure images using triplet networks

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npj Computational Materials 2020年第1期6卷 369-379页

作者： Michiel Larmuseau Michael Sluydts Koenraad Theuwissen Lode Duprez Tom Dhaene Stefaan Cottenier Center for Molecular Modeling Ghent UniversityTechnologiepark 46B-9052 ZwijnaardeBelgium Department of Electrical Energy MetalsMechanical Constructions and SystemsGhent UniversityTechnologiepark 46B-9052 ZwijnaardeBelgium IDLab Department of Information TechnologyGhent University-IMECTechnologiepark 126B-9052 ZwijnaardeBelgium OCAS NV/ArcelorMittal Global R&D Gent Pres.J.F.Kennedylaan 3B-9060 ZelzateBelgium

The microstructure of a material,typically characterized through a set of microscopy images of two-dimensional cross-sections,is a valuable source of information about the material and its properties.Every pixel of the image is a degree of freedom causing the dimensionality of the information space to be extremely high.This makes it difficult to recognize and extract all relevant information from the images.Human experts circumvent this by manually creating a lower-dimensional representation of the microstructure.However,the question of how a microstructure image can be best represented remains open.From the field of deep learning,we present triplet networks as a method to build highly compact representations of the microstructure,condensing the relevant information into a much smaller number of dimensions.We demonstrate that these representations can be created even with a limited amount of example images,and that they are able to distinguish between visually very similar microstructures.We discuss the interpretability and generalization of the representations.Having compact microstructure representations,it becomes easier to establish processing–structure–property links that are key to rational materials design.

关键词： networks compact microstructure

Erratum to:compact object candidates with K/M-dwarf companions from LAMOST low-resolution survey[Sci.China-Phys.Mech.Astron.65,229711(2022)]

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Science China(Physics,Mechanics & Astronomy) 2022年第10期65卷 157-158页

作者： Hui-Jun Mu Wei-Min Gu Tuan Yi Ling-Lin Zheng Hao Sou Zhong-Rui Bai Hao-Tong Zhang Ya-Juan Lei Cheng-Ming Li International Laboratory for Quantum Functional Materials of Henan and School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450001China Department of Astronomy Xiamen UniversityXiamen 361005China CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China

The paper“compact object candidates with K/M-dwarf com-panions from LAMOST low-resolution survey”[1]was pub-lished in SCIENCE CHINA Physics,Mechanics&Astronomy(65,229711(2022).doi:10.1007/s11433-021-1809-8).Due to an oversight on our part,some errors were made in the originally published paper.We apologize for these errors and offer the corresponding explanations and corrections for the readers.

关键词： compact dwarf survey

compact, submilliwatt, 2 × 2 silicon thermo-optic switch based on photonic crystal nanobeam cavities

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Photonics Research 2017年第2期5卷 108-112页

作者： HUANYING ZHOU CIYUAN QIU XINHONG JIANG QINGMING ZHU YU HE YONG ZHANG YIKAI SU RICHARD SOREF State Key Lab of Advanced Optical Communication Systems and Networks Department of Electronic Engineering Shanghai Jiao Tong University Engineering Department University of Massachusetts

We propose and experimentally demonstrate a 2×2 thermo-optic(TO) crossbar switch implemented by dual photonic crystal nanobeam(PCN)cavities within a silicon-on-insulator(SOI)platform.By thermally tuning the refractive index of silicon,the resonance wavelength of the PCN cavities can be red-shifted.With the help of the ultrasmall mode volumes of the PCN cavities,only～0.16 mW power is needed to change the switching state.With a spectral passband of 0.09 nm at the 1583.75 nm operation wavelength,the insertion loss(IL)and crosstalk(CT)performances were measured as IL(bar)=-0.2 dB,CT(bar)=-15 dB,IL(cross)=-1.5 dB,and CT(cross)=-15 dB.Furthermore,the thermal tuning efficiency of the fabricated device is as high as1.23 nm/mW.

关键词： PCN compact silicon thermo-optic switch based on photonic crystal nanobeam cavities submilliwatt mode SOI

Pseudoconformal equation of state in compact-star matter from topology change and hidden symmetries of QCD

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Science China(Physics,Mechanics & Astronomy) 2019年第11期62卷 87-92页

作者： Yong-Liang Ma Hyun Kyu Lee Won-Gi Paeng Mannque Rho Center for Theoretical Physics and College of Physics Jilin UniversityChangchun 130012China Department of Physics Hanyang UniversitySeoul 133-791Korea Rare Isotope Science Project Institute for Basic ScienceDaejeon 305-811Korea Institut de Physique Theorique CEA Saclay91191 Gif-sur-Yvette cedexFrance

We construct a new effective field theory approach to the equation of state(EoS), dubbed pseudo-confomal model 'PCM', for nuclear and compact star matter entirely in terms of effective hadron degrees of freedom. The possible transition at n ^(2-4)n0(where n0 is the normal nuclear matter density) from hadron degrees of freedom to strongly-coupled quark degrees of freedom,giving rise to a soft-to-hard changeover in the EoS that can accommodate the massive stars observed, is effectuated by the topology change at n1/2>~ 2n0 from skyrmions to half-skyrmions without involving local order-parameter fields. The mechanism exploits possible emergence of hidden scale and local symmetries of QCD at high density, leading to a precocious 'pseudo-conformal'sound velocity vs2= 1/3(in unit of c = 1) for n>~ 3n0. The resulting prediction signals a drastic departure from standard nuclear many-body theory in the density regime involved in the massive stars. We suggest that the tidal deformability implemented in gravitational waves coming from coalescing neutron stars in LIGO/Virgo-type observations could pin down the location of the topology change density n1/2.

关键词： equation of state compact star tidal deformability conformal sound velocity