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西藏羊八井中日合作ASγ实验进展与前景展望

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西藏大学学报（社会科学版） 2011年第2期26卷 103-111页

作者：陈天禄刘茂元单增罗布厉海金胡海冰袁爱芳雷文华次仁尼玛扎西桑珠丁晓红扎西次仁拉巴次仁孟宪茹西藏大学宇宙线教育部重点实验室西藏拉萨850000

文章简要介绍了西藏羊八井中日合作ASγ实验及发展历史,重点概述了该实验自1990年稳定运行以来取得的重要成果,对正在进行的实验升级计划进行了较为详细的介绍,展望了升级后的实验在宇宙线和甚高能γ天文领域中的前景。

关键词：宇宙线 “膝”区各向异性甚高能γ天文羊八井Asγ实验

Machine learning in polymer informatics

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InfoMat 2021年第4期3卷 353-361页

作者： Wuxin Sha Yan Li Shun Tang Jie tian Yuming Zhao Yaqing Guo Weixin Zhang Xinfang Zhang Songfeng lu Yuan-Cheng Cao Shijie Cheng State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhanChina Shenzhen Power Supply Col.Ltd. ShenzhenChina School of Computer Science and Technology Huazhong University of Science and TechnologyWuhanChina

Polymers have been widely used in energy storage,construction,medicine,aerospace,and so ***,the complexity of chemical composition and morphology of polymers has brought challenges to their *** to the integration of machine leaming algorithms and large data resources,the data-driven methods have opened up a new road for the development of poly-mer science and *** emerging polymer informatics attempts to accelerate the performance prediction and process optimization of new poly-mers by using machine learning models based on reliable *** the grad-ual supplement of currently available databases,the emergence of new databases and the continuous improvement of machine learning algorithms,the research paradigm of polymer informatics will be more efficient and widely *** on these points,this paper reviews the development trends of machine learning assisted polymer informatics and provides a simple introduc-tion for researchers in materials,artificial intelligence,and other fields.

关键词： polymer learning artificial

Extracting mineral alteration information using WorldView-3 data

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Geoscience Frontiers 2017年第5期8卷 1051-1062页

作者： Yaqin Sun Shufang tian Baogang Di School of Earth Science and Resources China University of Geosciences Beijing 100083 China

The multispectral commercial satellite-WorldView-3(WV-3) has the highest spatial, spectral and radiation resolutions among the satellites currently and can generate good data in the shortwave infrared(SWIR). The study area is located in the Pobei area of Xinjiang Uygur Autonomous Region, which is rich in mineral resources. The spectral analyses of some typical altered hydroxy-bearing, iron-bearing, and carbonate-bearing minerals could establish several Principal Component Analysis(PCA) models and mineral indices, using the visible and near infrared(VNIR) and the shortwave infrared(SWIR) subsystems of WV-3 data. In addition, the Spectral Angle Method and the spectrum index tool of ENVI software were used to extract the relevant alteration information. The WV-3 data is well suited for identifying hydroxy-bearing alteration with rich SWIR bands which distinguish Al-OH-bearing from MgOH-bearing alteration. Hence, this study provides a basis for the prediction of mineral resources in the Pobei area and sets the foundation for WV-3 data to be used as an important tool in extracting alteration information and prospecting practices.

关键词： WorldView-3 Alteration information Principal Component Analysis (PCA) Mineral indices Pobei Xinjiang

The distribution of the large partial quotients in continued fraction expansions

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Science China Mathematics 2023年第5期66卷 935-956页

作者： Bo Tan Chen tian Baowei Wang School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074China

The existence of large partial quotients destroys many limit theorems in the metric theory of continued *** achieve some variant forms of limit theorems,a common approach mostly used in practice is to discard the largest partial quotient,while this approach works in obtaining limit theorems only when there cannot exist two terms of large partial quotients in a metric *** by this,we are led to consider the metric theory of points with at least two large partial *** precisely,denoting by[a1(x),a2(x),...]the continued fraction expansion of x∈[0,1)and lettingψ:N→R+be a positive function tending to in nity as n→∞,we present a complete characterization on the metric properties of the set,i.e.,E(ψ)={x∈[0,1):∃16 k̸=ℓ6 n,ak(x)>ψ(n),aℓ(x)>ψ(n)for in nitely many n∈N}in the sense of the Lebesgue measure(the Borel-Bernstein type result)and the Hausdor dimension(the Jarnik type result).The main result implies that any nite deletion from a1(x)+……+an(x)cannot result in a law of large numbers.

关键词： continued fraction Hausdor dimension Borel-Bernstein theorem

Wake Numerical Simulation of Wind Field Based on Two Modified Wind Engineering Models

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第1期33卷 53-59页

作者： Yang Xiangsheng Zhao Ning tian Linlin Jiangsu Key Laboratory of Hi-Tech Research for Wind Turbine Design Nanjing University of Aeronautics & Astronautics

With the assumption of the Park model that the wake region is in linear expansion and the cross-wind is in multinomial and Gaussian distribution in wake region,one develops the Park-polynomial model and the ParkGaussian model to numerically simulate the wake flow field for a single wind *** with the measured data of wind farm and the wind tunnel test,it shows that the prediction precision of wake field has been improved obviously under the modified initial wake ***,both of the newly modified two models could well simulate the wind velocity in wake region,because the predicted results is approximately consistent with the test result,and the cross-wind distribution conforms to that of the real flow *** two models have still inherited many advantages of engineering models,such as simple form,easy-to-code,and high computational ***,the Park-Gaussian model is the best in overall performance among them.

关键词： Park-polynomial model Park-Gaussian model wind turbine wake

Data-driven parametric soliton-rogon state transitions for nonlinear wave equations using deep learning with Fourier neural operator

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Communications in Theoretical Physics 2023年第2期75卷 5-17页

作者： Ming Zhong Zhenya Yan Shou-Fu tian KLMM Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Mathematics China University of Mining and TechnologyXuzhou 221116China

In this paper,we develop the deep learning-based Fourier neural operator(FNO)approach to find parametric mappings,which are used to approximately display abundant wave structures in the nonlinear Schr?dinger(NLS)equation,Hirota equation,and NLS equation with the generalized PT-symmetric Scarf-II ***,we analyze the state transitions of different types of solitons(*** solitons,breathers,peakons,rogons,and periodic waves)appearing in these complex nonlinear wave *** checking the absolute errors between the predicted solutions and exact solutions,we can find that the FNO with the Ge lu activation function can perform well in all cases even though these solution parameters have strong influences on the wave ***,we find that the approximation errors via the physics-informed neural networks(PINNs)are similar in magnitude to those of the ***,the FNO can learn the entire family of solutions under a given distribution every time,while the PINNs can only learn some specific solution each *** results obtained in this paper will be useful for exploring physical mechanisms of soliton excitations in nonlinear wave equations and applying the FNO in other nonlinear wave equations.

关键词： deep learning Fourier neural operator solitonrogon state transition nonlinear Schrödinger equation hirota equation

Prospective Roles of Scanning Photoelectrochemical Microscopy in Microbial Hybrid Photosynthesis

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Chinese Journal of Chemistry 2022年第24期40卷 3013-3016页

作者： Xiaochun tian Rui Bai Feng Zhao CAS Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamenFujian361021 China

Microbial hybrid photosynthesis has attracted great interests in recent years since it integrates the advantages of natural and artificial photosynthesis for solar-to-chemical conversion. Coupling a light source with scanning electrochemical microscopy, scanning photoelectrochemical microscopy (SPECM) shows great potential in investigating the interfacial reactions of microbial hybrid photosynthesis. In this Emerging Topic, the potential roles of SPECM in revealing biotic–abiotic interfacial electron transfer mechanisms and calculating electrode process kinetics are proposed for hybrid photosynthesis, and this will also inspire the applications of SPECM in the fields including biomineralization, photocatalytic-biodegradation and microbial photoelectrochemical systems.

关键词： Electron transfer Interfaces Photosynthesis Scanning electrochemical microscopy Scanning photoelectrochemical microscopy Semi-artificial photosynthesis

ERROR ESTIMATION FOR NUMERICAL METHODS USING THE ULTRA WEAK VARIATIONAL FORMULATION IN MODEL OF NEAR FIELD SCATTERING PROBLEM

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Journal of Computational Mathematics 2014年第5期32卷 491-506页

作者： tian luan Fuming Ma Minghui Liu School of Mathematics and Statistics Beihua University Jilin 132013 China Institute of Mathematics Jilin University Changchun 130012 China

In this paper, we investigate the use of ultra weak variational formulation to solve a wave scattering problem in near field optics. In order to capture the sub-scale features of waves, we utilize evanescent wave functions together with plane wave functions to approximate the local properties of the field. We analyze the global convergence and give an error estimation of the method. Numerical examples are also presented to demonstrate the effectiveness of the strategy.

关键词： Helmholtz equation Ultra weak variational formulation Plane wave function,Evanescent wave function Absorbing boundary condition.

Ideal Strengths and Bonding Properties of PuO_(2)under Tension

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Chinese Physics Letters 2011年第4期28卷 178-181页

作者： WANG Bao-tian ZHANG Ping Institute of Theoretical Physics and the Department of Physics Shanxi UniversityTaiyuan 030006 LCP Institute of Applied Physics and Computational MathematicsBeijing 100088

We perform a first-principles computational tensile test on PuO_(2)based on density-functional theory within a local density approximation(LDA)+U formalism to investigate its structural,mechanical,magnetic and intrinsic bonding properties in four representative directions:[001],[100],[110]and[111].The stress-strain relations show that the ideal tensile strengths in the four directions are 81.2,80.5,28.3 and 16.8 GPa at strains of 0.36,0.36,0.22 and 0.18,***[001]and[100]directions are prominently stronger than the other two directions since more Pu-0 bonds participate in the pulling *** charge and density of state analysis along the[001]direction,we find that the strong mixed ioni%ovalent character of the Pu-0 bond is weakened by tensile strain and PuO_(2)will exhibit an insulator-to-metal transition after tensile stresses exceeding about 79 GPa.

关键词： process strain directions