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人工智能在气象数据集研制中的应用综述

人民长江 2025年第1期56卷 88-96页

作者：李波潘勐孙越中国长江电力股份有限公司湖北宜昌443002 湖北省气象信息与技术保障中心湖北武汉430074

长序列、高时空分辨率气象数据集对气象业务和科研具有重要意义,但是应用过程中存在数据质量低、空间分辨率不足等问题。随着人工智能的发展,机器学习以及深度学习算法在气象领域逐步开展应用。针对气象数据集研制中的技术难点问题,梳... 详细信息

长序列、高时空分辨率气象数据集对气象业务和科研具有重要意义,但是应用过程中存在数据质量低、空间分辨率不足等问题。随着人工智能的发展,机器学习以及深度学习算法在气象领域逐步开展应用。针对气象数据集研制中的技术难点问题,梳理了人工智能技术的4个关键应用场景,即观测数据的质量控制、缺测数据的插补和重构、多源数据的融合以及低分辨网格数据的降尺度,对各类机器学习模型在上述场景应用中的优势和不足进行了综述,并采用文献计量方法对研究前沿及发展趋势进行了定量分析。研究表明:相比传统方法,人工智能算法在计算效率、结果准确性、应用灵活性等方面更具竞争力。建议从建立高质量训练数据集、加强多源数据和异构数据的应用以及探索基于气象数据物理机制的建模等多个方面,进一步推动人工智能在气象数据产品研制中的应用。

关键词：气象数据集人工智能机器学习深度学习质量控制降尺度

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Precise determination of the pole position of the exotic z_(c)(3900)

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Science china(Physics,Mechanics & Astronomy) 2024年第9期67卷 84-90页

作者： Yun-Hua chen meng-Lin Du Feng-Kun Guo School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China School of Physics University of Electronic Science and Technology of ChinaChengdu 611731China cAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Peng Huanwu collaborative center for Research and Education Beihang UniversityBeijing 100191China

We perform a unified description of the experimental data of the π^(+)π^(-)and J/ψπ^(±)invariant mass spectra for e^(+)e^(-)→J/ψπ^(+)π^(-)and the D^(0)D^(*-)mass spectrum for e^(+)e^(-)→D^(0)D^(*-)π^(+)at e^(+)e^(-)center-of-mass energies 4.23 and 4.26 *** analysis takes into account open-charm meson loops that contain triangle singularities,the J/ψπ-DD^(*)coupled-channel interaction respecting unitarity,and the strong ππ-KK final state interaction using dispersion *** analysis leads to a precise determination of the z_(c)(3900)pole with the pole mass and width(3880.7±1.7_(stat)±22.4_(syst))MeV and(35.9±1.4_(stat)±15.3_(syst))MeV,respectively,and hints at that the DD^(*)molecular and non-molecular components are of similar importance in the z_(c)(3900)formation.

关键词： exotic hadrons dispersion relations final state interaction triangle singularity

Grids of stellar models including second harmonic and colors:solar composition(z = 0.0172,X = 0.7024)

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Research in Astronomy and Astrophysics 2015年第12期15卷 2244-2262页

作者： Mutlu Y?ld?z Ege University Department of Astronomy and Space Sciences

Grids of stellar evolution omy/astrophysics, such as planet hosting are required in many fields of astron- stars, binaries, clusters, chemically peculiar stars, etc. In this study, a grid of stellar evolution models with updated ingredients and recently determined solar abundances is presented. The solar values for the initial abundances of hydrogen, heavy elements and mixing-length parameter are 0.0172, 0.7024 and 1.98, respectively. The mass step is small enough （0.01 M） that interpolation for a given star mass is not required. The range of stellar mass is 0.74 to 10.00M. We present results in different forms of tables for easy and general appli- cation. The second stellar harmonic, required for analysis of apsidal motion of eclips- ing binaries, is also listed. We also construct rotating models to determine the effect of rotation on stellar structure and derive fitting formulae for luminosity, radius and the second harmonic as a function of rotational parameter. We also compute and list colors and bolometric corrections of models required for transformation between theo- retical and observational results. The results are tested for the Sun, the Hyades cluster, the slowly rotating chemically peculiar Am stars and eclipsing binaries with apsidal motion. The theoretical and observational results along isochrones are in good agree- ment. The grids are also applicable to rotating stars provided that equatorial velocity is given.

关键词： stars: interior -- stars: evolution -- binaries: eclipsing -- stars: chemi-cally peculiar

Numerical investigation on the flowfield of “swallowtail” cavity for supersonic mixing enhancement

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Acta Mechanica Sinica 2009年第1期25卷 37-44页

作者： c. Wang z. Jiang z. Hu J. Lu Institute or Mechanics. chinese Academy of Sciences 100190 Beijing China RecAPT Gyeongsang National University JinjuKyeongnam 660-701 South Korea

A ＂swallowtail＂ cavity for the supersonic combustor was proposed to serve as an efficient flame holder for scramjets by enhancing the mass exchange between the cavity and the main flow. A numerical study on the ＂swallow- tail＂ cavity was conducted by solving the three-dimensional Reynolds-averaged Navier-Stokes equations implemented with a k-e turbulence model in a multi-block mesh. Turbu- lence model and numerical algorithms were validated first, and then test cases were calculated to investigate into the mechanism of cavity flows. Numerical results demonstrated that the certain mass in the supersonic main flow was sucked into the cavity and moved spirally toward the combustor walls. After that, the flow went out of the cavity at its lateral end, and finally was efficiently mixed with the main flow. The comparison between the ＂swallowtail＂ cavity and the conventional one showed that the mass exchanged between the cavity and the main flow was enhanced by the lateral flow that was induced due to the pressure gradient inside the cavity and was driven by the three-dimensional vortex ring generated from the ＂swallowtail＂ cavity structure.

关键词： Supersonic mixing - Flame holder "Swallowtail" cavity - combustion ignition Numerical simulation

Advances in centrifugal Separators for Particulate Matter control from Stationary Sources

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Journal of Thermal Science 2002年第3期11卷 283-288页

作者： z.c.Tan University of Illinois Urbana USA

This paper summarized recent developments in centrifugal separators for particulate matter (PM) emission control. Airborne particulate matter, which is responsible for many health and environmental problems, is generated mostly from combustion processes in stationary sources such as house burners and power plants and other production facilities, except field dust. Reverse flow cyclones are centrifugal separators having been widely used for industrial particulate matter removal. Typical pressure drops of these cyclones for air cleaning are 500 Pa or higher, and were believed to be only able to separate particles larger than 10 μm. An aerodynamic deduster that could separate particles as small as 1μm at a pressure drop of 200 Pa was recently developed. Field evaluation showed that the deduster can be effectively used in reducing particulate matter emission from stationary sources.

关键词： particulate matter emission control centrifugal separator cyclones aerodynamic deduster particle cut size.

Experimental investigation of hypersonic flight-duplicated shock tunnel characteristics

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Acta Mechanica Sinica 2021年第3期37卷 422-433,I0002页

作者： c K.Yuan z.L.Jiang Institute of Mechanics Chinese Academy of SciencesBeijing 100190China University of chinese Academy of Sciences Beijing 100190China

Hypersonic air-breathing propulsion is one of the key techniques for future aviation and the ground aerodynamic testing for full scale test models with sufficient test time at flight conditions is of fundamental importance for verifying hypersonic air-breathing *** on the backward detonation-driven concept,the hypersonic flight-duplicated shock tunnel(or JF-12 shock tunnel)has been successfully constructed and *** facility is capable of reproducing airflow for Mach numbers ranging from 5 to 9 at an altitude of 25-50 km,with a test duration of more than 100 *** quantify the performance of the shock tunnel,experiments were conducted to investigate the aerodynamic characteristics of the test flows and the effects of several critical techniques that play important roles in the operation of the shock *** stagnation pressure was constant within士5%and the average stagnation pressure varied by less than 0.048%/*** variation of the stagnation pressure in repeated experiments is less than 2.0%,indicating the good repeatability of the wind *** non-uniformity of the Mach number in the core flow field at the nozzle exit was within士2.5%.Additional,a uniform flow field is established upstream of the nozzle *** axial gradients of the flow field are small since the Mach number varies less than 1.7%/*** regarding the ignition technology,diaphragm ruptures,detonation driver capacity,incident shock-wave decay,and tunnel operation mode are also *** findings of this study are not only helpful for operating the shock tunnel,but can also assist the future development of hypersonic wind tunnels.

关键词： Hypersonics Shock tunnels Flow characteristics

Primary dendrite growth kinetics and rapid solidification mechanism of highly undercooled Ti-Al alloys

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Journal of Materials Science & Technology 2020年第5期40卷 47-53页

作者： z.c.Luo H.P.Wang Department of Applied Physics Northwestern Polytechnical UniversityXi’an 710072China

The rapid solidification processes of undercooled Ti-(47,50,54)at.%Al alloys were investigated by electromagnetic levitation(EML)method combined with a high-speed photoelectric *** maximum undercoolings of the three liquid alloys were 376 K,352 K and 316 K,*** processes corresponding to the primary dendrite growth and subsequent phase transition were recorded at various *** primary dendrite growth velocity V meets a double exponential relationship with the undercooling ***,a novel formula with physical meaning is proposed to explain that the more ordered liquid metal atoms accelerate the primary dendrite *** recalescences are found at all undercoolings for Ti-47 at.%Al alloy and at high undercoolings for Ti-50 at.%Al *** microstructures of solidified Ti-47 at.%Al alloys successively appear as coarse lamellar dendrites and finally evolve to refined parallel lamellar dendrites with the increasing *** T rises,the microstructures of solidified Ti-50 at.%Al alloys appear from coarse primary dendrites and interdendritic dendrites to refined lamellar *** the process from low undercooling to high undercooling,the primary phase of undercooled Ti-54 at.%Al alloys changes from r-Ti(r)to r-TiAl(r)and the microstructures of solidified alloys evolve from spherical primary dendrites and matrix phases to cellular dendrite ***,for the Ti-(47,50)at.%Al,the transformation temperature of metastable intermediateγphase decreases with the increase of ***,the microhardness of the three solidified alloys reaches the maximum when the undercoolings are 185 K,270 K and 316 K,respectively.

关键词： Electromagnetic levitation Rapid solidification Dendrite growth Microstructure Microhardness

Ion-modulation optoelectronic neuromorphic devices:mechanisms,characteristics,and applications

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Journal of Semiconductors 2025年第2期46卷 24-36页

作者： Xiaohan meng Runsheng Gao Xiaojian zhu Run-Wei Li cAS Key Laboratory of Magnetic Materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of Sci-encesNingbo 315201China zhejiang Province Key Laboratory of Magnetic Materials and Application Technology Ningbo Institute of Materials Technology andEn gineer-ingChinese Academy of SciencesNingbo 315201China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

The traditional von Neumann architecture faces inherent limitations due to the separation of memory and computa-tion,leading to high energy consumption,significant latency,and reduced operational *** computing,inspired by the architecture of the human brain,offers a promising alternative by integrating memory and computational func-tions,enabling parallel,high-speed,and energy-efficient information *** various neuromorphic technologies,ion-modulated optoelectronic devices have garnered attention due to their excellent ionic tunability and the availability of multi-dimensional control *** review provides a comprehensive overview of recent progress in ion-modulation optoelec-tronic neuromorphic *** elucidates the key mechanisms underlying ionic modulation of light fields,including ion migra-tion dynamics and capture and release of charge through ***,the synthesis of active materials and the proper-ties of these devices are analyzed in *** review also highlights the application of ion-modulation optoelectronic devices in artificial vision systems,neuromorphic computing,and other bionic ***,the existing challenges and future direc-tions for the development of optoelectronic neuromorphic devices are discussed,providing critical insights for advancing this promising field.

关键词： ion migration optoelectronic modulation optoelectronic device neuromorphic computing artificial vision system

A cellulose-based lithium-ion battery separator with regulated ionic transport and high thermal stability for extreme environments

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Nano Research 2025年第1期18卷 315-322页

作者： Kun-Peng Yang Song Xie zi-meng Han Hao-cheng Liu chong-Han Yin Wen-Bin Sun zhang-chi Ling Huai-Bin Yang De-Han Li Qing-Fang Guan Shu-Hong Yu Department of chemistry New Cornerstone Science LaboratoryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsDivision of Nanomaterials&ChemistryHefei National Research Center for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Institute of Innovative Materials Department of Materials Science and EngineeringDepartment of ChemistrySouthern University of Science and TechnologyShenzhen 518055China

Separators play a critical role in lithium-ion ***,the restrictions of thermal stability and inferior electrical performance in commercial polyolefin separators significantly limit their applications under harsh ***,we report a cellulose-assisted self-assembly strategy to construct a cellulose-based separator massively and *** an ultrahigh ionic conductivity in electrolytes of 3.7 mS·cm^(-1) and the ability to regulate ion transport,the obtained separator is a promising alternative for high-performance lithium-ion *** addition,integrated with high thermal stability,the cellulose-based separator endows batteries with high safety at high temperatures,greatly expanding the application scenarios of energy storage devices in extreme environments.

关键词： lithium-ion batteries bio-inspired materials battery separators cellulose nanofiber ultrahigh ionic conductivity high safety