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A New Sparse Recovery Method for the Inverse Acoustic Scattering Problem

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Acta Mathematicae Applicatae Sinica 2020年第1期36卷 49-66页

作者： Chang-long WANG Jun-xiong jiA ji-gen PENG Shou-jin LIN Ministry Key Laboratory of Electronic Information Countermeasure and Simulation Xidian UniversityXi'an 710049China School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049China School of Mathematics and Information Science Guangzhou UniversityGuangzhou 510006China LMTOR Intellignet Equipment Co. LtdNo.5 Fengsheng RoadZhongshanChina

Based on sparse information recovery,we develop a new method for locating multiple multiscale acoustic ***,with the prior information of the scatterers’shape,we reformulate the location identification problem into a sparse information recovery model which brought the power of sparse recovery method into this type of inverse scattering ***,the new model can advance the judgment of the existence of alternative scatterers and,in the meantime,conclude the number and locating of each existing ***,as well known,the core model(l0-minimization)in sparse information recovery is an NP-hard *** to the characteristics of the proposed sparse model,we present a new substitute method and give a detailed theoretical analysis of the new substitute *** on the properties of the new model,we construct a basic algorithm and an improved ***,we verify the validity of the proposed method through two numerical experiments.

关键词： sparse recovery acoustic scatterer l0-minimization substitute function

Molten salt synthesis of porous carbon and its application in supercapacitors: A review

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Journal of Energy Chemistry 2021年第10期30卷 622-640,I0016页

作者： Zhongya Pang Guangshi Li Xiaolu xiong Li ji Qian Xu Xingli Zou xionggang Lu State Key Laboratory of Advanced Special Steel&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai University99#Shangda RoadShanghai 200444China State Key Laboratory of ASIC and System School of MicroelectronicsFudan University825#Zhangheng RoadShanghai 200433China

Carbon materials have taken an important role in supercapacitor applications due to their outstanding features of large surface area,low price,and stable physicochemical *** research efforts have been devoted to the development of novel synthesis strategy for the preparation of porous carbon materials in recent *** particular,molten salt strategy represents an emerging and promising method,whereby it has shown great potential in achieving tailored production of porous *** has been proved that the molten salt-assisted production of carbon via the direct carbonization of carbonaceous precursors is an effective ***,with the incorporation of electrochemical technology,molten salt synthesis of porous carbon has become flexible and ***,this review focuses on the mainstream molten salt synthesis strategies for the production of porous carbon materials,which includes direct molten salt carbonization process,capture and electrochemical conversion of CO_(2)to value-added carbon,electrochemical exfoliation of graphite to graphene-based materials,and electrochemical etching of carbides to new-type carbide-derived carbon *** reaction mechanisms and recent advances for these strategies are reviewed and discussed *** morphological and structural properties and capacitive performances of the obtained carbon materials are summarized to reveal their appealing points for supercapacitor ***,the opportunities and challenges of the molten salt synthesis strategy for the preparation of carbon materials are also discussed in this review to provide inspiration to the future researches.

关键词： Molten salt synthesis Porous carbon CO_(2)conversion Graphene Carbide-derived carbon

Chaotic microlasers caused by internal mode interaction for random number generation

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Light(Science & Applications) 2022年第7期11卷 1565-1574页

作者： chun-Guang Ma jin-Long Xiao Zhi-xiong Xiao Yue-De Yang Yong-Zhen Huang State Key Laboratory of Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Material Science and Optoelectronic Engineering University of Chinese Academy of SciencesBeijing 100049China

Chaotic semiconductor lasers have been widely investigated for generating unpredictable random numbers,especially for lasers with external optical ***,chaotic lasers under external feedback are hindered by external feedback loop time,which causes correlation peaks for chaotic ***,we demonstrate the first self-chaotic microlaser based on internal mode interaction for a dual-mode microcavity laser,and realize random number generation using the self-chaotic laser *** adjusting mode frequency interval close to the intrinsic relaxation oscillation frequency,nonlinear dynamics including self-chaos and period-oscillations are predicted and realized numerically and experimentally due to internal mode *** internal mode interaction and corresponding carrier spatial oscillations pave the way of mode engineering for nonlinear dynamics in a solitary *** findings provide a novel and easy method to create controllable and robust optical chaos for high-speed random number generation.

关键词： mode random chaotic

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德昂族春节的兴起与中华文化认同

中国非物质文化遗产 2025年第1期 64-71页

作者：熊威华中师范大学文学院

改革开放以来,春节在德昂族聚居区兴起,并逐渐成为德昂族节日体系的重要组成部分。德昂族春节的兴起,本质上是礼俗互动的结果,形成了既符合传统春节习俗,又带有德昂族文化特征的节日文化,表征出中华文化的多元一体性。德昂族春节的发展... 详细信息

改革开放以来,春节在德昂族聚居区兴起,并逐渐成为德昂族节日体系的重要组成部分。德昂族春节的兴起,本质上是礼俗互动的结果,形成了既符合传统春节习俗,又带有德昂族文化特征的节日文化,表征出中华文化的多元一体性。德昂族春节的发展过程与实践,彰显出德昂族的中华文化认同。春节在德昂族聚居区的深化发展,进一步强化了德昂族的中华文化认同。因此,应该高度重视传统节日的文化价值,夯实铸牢中华民族共同体意识的文化基础。

关键词：德昂族春节中华文化认同铸牢中华民族共同体意识

Seismic study of solar convection and overshooting: results of nonlocal convection

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Research in Astronomy and Astrophysics 2013年第9期13卷 1127-1140页

作者： chun-Guang Zhang Li-Cai Deng Da-Run xiong Jrgen Christensen-Dalsgaard Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences Purple Mountain Observatory Chinese Academy of Sciences Stellar Astrophysics Centre Department of Physics and Astronomy Aarhus University

Local mixing-length theory is incapable of describing nonlocal phenom- ena in stellar convection, such as overshooting. Therefore standard solar models con- structed with local mixing-length theory significantly deviate from the Sun at the boundaries of the convection zone, where convection becomes less efficient and nonlo- cal effects are important. The differences between observed and computed frequencies mainly come from the region near the surface, while the localized difference in sound speed is just below the convective envelope. We compute a solar envelope model using xiong＇s nonlocal convection theory, and carry out helioseismic analysis. The nonlocal model has a smooth transition at the base of the convection zone, as revealed by helio- seismology. It reproduces solar frequencies more accurately, and reduces the localized difference in sound speed between the Sun and standard solar models.

关键词： convection -- Sun: interior -- Sun: helioseismology

Semi-Supervised Clustering Algorithm Based on Deep Feature Mapping

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Intelligent Automation & Soft Computing 2023年第7期37卷 815-831页

作者： xiong Xu chun Zhou Chenggang Wang Xiaoyan Zhang Hua Meng Southwest China Institute of Electronic Technology Chengdu610036China School of Mathematics Southwest Jiaotong UniversityChengdu611756China

Clustering analysis is one of the main concerns in data mining.A common approach to the clustering process is to bring together points that are close to each other and separate points that are away from each ***,measuring the distance between sample points is crucial to the effectiveness of *** features by label information and mea-suring the distance between samples by these features is a common supervised learning method to reconstruct distance ***,in many application scenarios,it is very expensive to obtain a large number of labeled *** this paper,to solve the clustering problem in the few supervised sample and high data dimensionality scenarios,a novel semi-supervised clustering algorithm is proposed by designing an improved prototype network that attempts to reconstruct the distance metric in the sample space with a small amount of pairwise supervised information,such as Must-Link and Cannot-Link,and then cluster the data in the new metric *** core idea is to make the similar ones closer and the dissimilar ones further away through embedding *** experiments on both real-world and synthetic datasets show the effectiveness of this *** clustering metrics on various datasets improved by 8%compared to the comparison algorithm.

关键词： Metric learning semi-supervised clustering prototypical network feature mapping

A magnetic model for low/hard state of black hole binaries

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Research in Astronomy and Astrophysics 2016年第3期16卷 33-42页

作者： Yong-chun Ye Ding-xiong Wang Chang-Yin Huang Xiao-Feng Cao School of Physics Huazhong University of Science and Technology School of Physics and Optoelectronic Engineering Yangtze University School of Physics and Electronic Information Hubei University of Education

A magnetic model for the low/hard state （LHS） of two black hole X-ray binaries （BHXBs）, H1743-322 and GX 339-4, is proposed based on transport of the magnetic field from a companion into an accretion disk around a black hole （BH）. This model consists of a truncated thin disk with an inner advection-dominated accretion flow （ADAF）. The spectral profiles of the sources are fitted in agreement with the data observed at four different dates corresponding to the rising phase of the LHS. In addition, the association of the LHS with a quasi-steady jet is modeled based on transport of magnetic field, where the Blandford-Znajek （BZ） and Blandford-Payne （BP） processes are invoked to drive the jets from BH and inner ADAE It turns out that the steep radio/X-ray correlations observed in H 1743-322 and GX 339-4 can be interpreted based on our model.

关键词： accretion accretion disks -- black hole physics -- magnetic field-- stars: individual (H 1743- 322) -- stars: individual (GX 339-4)

Optical Torque Exerted on a Rotator under Illumination of a Vortex Beam

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Chinese Physics Letters 2012年第6期29卷 145-148页

作者： LI Dong-Hua PU ji-xiong WANG Xi-Qing College of Information Science&Engineering Huaqiao UniversityXiamen 361021 College of Physical Science and Technology Southwest Jiaotong UniversityChengdu 610031

We investigate the torque on a specially shaped rotator produced by a vortex *** formulas for the torque along x,y and z directions axe derived,and numerical calculation is *** is found that for the specially shaped rotator,the torque brought by the Laguerre-Gauss (LG) vortex beam is dependent upon the angle of the facet for each part of the rotator,and the topological charge of the vortex *** is shown that torque is generated from both the light momentum and orbital angular momentum (OAM) of the incident vortex beam,indicating that we can control the rotation of the rotator by modulating the OAM of the incident light beam.

关键词： vortex momentum shaped

Efficient turbulent compressible convection in the deep stellar atmosphere

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Chinese Journal of Astronomy and Astrophysics 2009年第1期9卷 102-114页

作者： chun-Lin Tian Li-Cai Deng Kwing-Lam Chan Da-Run xiong National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Department of Mathematics Hong Kong University of Science and Technology Hong Kong China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

We report on an application of gas-kinetic BGK scheme to the computation of turbulent compressible convection in the stellar interior. After incorporating the Sub-grid Scale （SGS） turbulence model into the BGK scheme, we tested the effects of numerical parameters on the quantitative relationships among the thermodynamic variables, their fluctuations and correlations in a very deep, initially gravity-stratified stellar atmosphere. Comparison indicates that the thermal properties and dynamic properties are dominated by different aspects of numerical models separately. An adjustable Deardorff constant in the SGS model cu, = 0.25 and an amplitude of artificial viscosity in the gas-kinetic BGK scheme C2 = 0 are appropriate for the current study. We also calculated the densityweighted auto- and cross-correlation functions in xiong＇s turbulent stellar convection theory based on which the gradient type of models of the non-local transport and the anisotropy of the turbulence were preliminarily studied. No universal relations or constant parameters were found for these models.

关键词： convection -- hydrodynamic -- turbulence -- method: numerical -- stars atmosphere