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Exploring the sources of p-mode frequency shifts in the CoRoT target HD 49933

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Research in Astronomy and Astrophysics 2014年第6期14卷 683-692页

作者： zhi-E Liu Shao-Lan Bi Wu-Ming Yang Tan-Da Li Kang Liu zhi-Jia Tian zhi-shuai ge Jie Yu Department of Astronomy Beijing Normal University Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Science

Oscillations of the solar-like star HD 49933 have been thoroughly observed by CoRot. Two dozen frequency shifts, which are closely related to the change in magnetic activity, have been measured. To explore the effects of magnetic activity on frequency shifts, we calculate frequency shifts for the radial and l=1 p-modes of HD 49933 with the general variational method, which evaluates the shifts using a spa- tial integral of the product of a kernel and some sources. The theoretical frequency shifts reproduce the observation well. The magnitudes and positions of the sources are determined according to a χ2 criterion. We predict the source that contributes to both the l = 0 and l= 1 modes is located 0.48 - 0.62 Mm below the surface of the star. In addition, based on the assumption that A0 is proportional to the change in the MglI activity index △iMgⅡ, we obtain that the change in MgⅡ index between the minimum and maximum of the cycle during the period of HD 49933 is about 0.665. The magnitude of the frequency shifts compared to the Sun already demonstrates that HD 49933 is much more active than the Sun, which is further confirmed in this pa- per. Furthermore, our calculation of the frequency shifts for l = 1 modes indicates the variation of turbulent velocity in the stellar convective zone may be an important source for the l = 1 shifts.

关键词： stars: individual (HD 49933) -- stars: evolution -- stars: oscillation --stars: modeling

Stellar parameters of main sequence turn-off star candidates observed with LAMOST and Kepler

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Research in Astronomy and Astrophysics 2017年第1期17卷 55-70页

作者： Ya-Qian Wu Mao-Sheng Xiang Xian-Fei Zhang Tan-Da Li Shao-Lan Bi Xiao-Wei Liu Jian-Ning Fu Yang Huang zhi-Jia Tian Kang Liu zhi-shuai ge Xin He Jing-Hua Zhang Department of Astronomy Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Department of Astronomy Peking University

Main sequence turn-off （MSTO） stars since their ages can be robustly estimated from have advantages as indicators of Galactic evolution atmospheric parameters. Hundreds of thousands of MSTO stars have been selected from the LAMOST Galactic survey to study the evolution of the Galaxy, and it is vital to derive accurate stellar parameters. In this work, we select 150 MSTO star candidates from the MSTO star sample of Xiang that have asteroseismic parameters and determine accurate stellar parameters for these stars by combining asteroseismic parameters deduced from Kepler photometry and atmospheric parameters deduced from LAMOST spectra. With this sample, we examine the age determination as well as the contamination rate of the MSTO star sample. A comparison of age between this work and Xiang shows a mean difference of 0.53 Gyr （7%） and a dispersion of 2.71 Gyr （28%）. The results show that 79 of the candidates are MSTO stars, while the others are contaminations from either main sequence or sub-giant stars. The contamination rate for the oldest stars is much higher than that for younger stars. The main cause for the high contamination rate is found to be the relatively large systematic bias in the LAMOST surface gravity estimates.

关键词： stars: fundamental parameters - stars evolution - stars asteroseismology

Production of exotic neutron-deficient isotopes near N, Z=50 in multinucleon transfer reactions

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Chinese Physics C 2019年第6期43卷 51-58页

作者： Xin-Xin Xu gen Zhang Jing-Jing Li Bing Li Cheikh A.T.Sokhna1 Xin-Rui Zhang Xiu-Xiu Yang Shi-Hui Cheng Yu-Hai Zhang zhi-shuai ge Cheng Li Zhong Liu Feng-Shou Zhang Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and Technology Beijing Normal University Beijing 100875 China Beijing Radiation Center Beijing 100875 China Institute of Modem Physics Chinese Academy of Sciences Lanzhou 730000 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

The multinucleon transfer reaction in the collisions of 40 Ca+^124 Sn at Ec.m.= 128.5 MeV is investigated using the improved quantum molecular dynamics model. The measured angular distributions and isotopic distributions of the products are reproduced reasonably well by the calculations. The multinucleon transfer reactions of 40 Ca+^112 Sn, 58 Ni+^112 Sn, 106 Cd+^112 Sn, and 48 Ca+^112 Sn are also studied. This demonstrates that the combinations of neutron-deficient projectile and target are advantageous for the production of exotic neutron-deficient nuclei near N,Z =50. The charged particles’ emission plays an important role at small impact parameters in the de-excitation processes of the system. The production cross sections of the exotic neutron-deficient nuclei in multinucleon transfer reactions are much larger than those measured in the fragmentation and fusion-evaporation reactions. Several new neutron-deficient nuclei can be produced in the 106 Cd+^112 Sn reaction. The corresponding production cross sections for the new neutron-deficient nuclei,101,112 Sb,103 Te,and 106,107) I,are 2.0 nb,4.1 nb,6.5 nb,0.4 μb and 1.0 μb,respectively.

关键词： production cross-sections exotic neutron-deficient nuclei production cross sections

图像处理中CNN与视觉Transformer混合模型研究综述

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计算机科学与探索 2025年第1期19卷 30-44页

作者：郭佳霖智敏殷雁君葛湘巍内蒙古师范大学计算机科学技术学院

卷积神经网络（CNN）与视觉Transformer是目前图像处理领域中两大重要的深度学习模型，两者经过多年来不断的研究与进步，已在该领域取得了非凡的成就。近些年来，CNN与视觉Transformer的混合模型正在逐步兴起，广泛的研究不断克服两种... 详细信息

卷积神经网络（CNN）与视觉Transformer是目前图像处理领域中两大重要的深度学习模型，两者经过多年来不断的研究与进步，已在该领域取得了非凡的成就。近些年来，CNN与视觉Transformer的混合模型正在逐步兴起，广泛的研究不断克服两种模型存在的弱项，高效地发挥出各自的亮点，在图像处理任务中表现出优异的效果。基于CNN与视觉Transformer混合模型进行深入阐述。总体概述了CNN与Vision Transformer模型的架构和优缺点，并总结混合模型的概念及优势。围绕串行结构融合方式、并行结构融合方式、层级交叉结构融合方式以及其他融合方式等四个方面全面回顾梳理了混合模型的研究现状和实际进展，并针对各种融合方式的主要代表模型进行总结与剖析，从多方面对典型混合模型进行评价对比。多角度叙述了混合模型在图像识别、图像分类、目标检测和图像分割等实际图像处理特定领域中应用研究，展现出混合模型在具体实践中的适用性和高效性。深入分析混合模型未来研究方向，并为后续该模型在图像处理中的研究与应用提出展望。

关键词：卷积神经网络(CNN) 视觉Transformer 混合模型图像处理深度学习

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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第01期 288-296页

作者： shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

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Batch process monitoring based on multilevel ICA-PCA

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第8期9卷 1061-1069页

作者： zhi-qiang ge zhi-huan SONG State Key Lab of Industrial Control Technology Institute of Industrial Process Control Zhejiang University Hangzhou 310027 China

In this paper, we describe a new batch process monitoring method based on multilevel independent component analysis and principal component analysis (MLICA-PCA). Unlike the conventional multi-way principal component analysis (MPCA) method, MLICA-PCA provides a separated interpretation for multilevel batch process data. Batch process data are partitioned into two levels: the within-batch level and the between-batch level. In each level, the Gaussian and non-Gaussian components of process information can be separately extracted. I2, T2 and SPE statistics are individually built and monitored. The new method facilitates fault diagnosis. Since the two variation levels are decomposed, the variables responsible for faults in each level can be identified and interpreted more easily. A case study of the Dupont benchmark process showed that the proposed method was more efficient and interpretable in fault detection and diagnosis, compared to the alternative batch process monitoring method.

关键词： Multilevel Independent component analysis (ICA) Principal component analysis (PCA) Batch process monitoring Non-Gaussian

3D coarse-grained DPM simulation of the MIP reaction-regeneration loop

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Particuology 2024年第6期89卷 57-66页

作者： Yanhao Ye shuai Zhang Ji Xu Wei ge State Key Laboratory of Mesoscience and Engineering(formerly State Key Laboratory of Multiphase Complex Systems) Institute of Process EngineeringChinese Academy of SciencesBeijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China

The reactor-regenerator loop is the core facility of the maximizing iso-paraffin(MIP)*** the discrete particle method(DPM)simulation can provide detailed information at the particle scale,it has been unable to simulate such a complex loop system due to limitations of coarse-grained(CG)models,computing software,and *** this study,a newly proposed soft-shell CG-DPM model with a CG ratio of up to 800 is used to simulate a 3.5 Mt/a industrial-scale MIP reactor-regenerator *** solid fraction distribution obtained is found to agree well with in-situ *** properties including the distribution of solid fraction,gas and solid velocity,standard derivation of solid fraction with time,temporal distribution of the flow field,and particle residence time distribution are measured in the simulation,which are meaningful to better design and operate such systems in the future.

关键词： Discrete particle method Coarse-grain Maximizing iso-paraffins Full-loop Reaction-regeneration system

Preparation of a novel composite electrode based on N-doped TiO_2-coated Na Y zeolite membrane and its photoelectrocatalytic performance

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Chinese Chemical Letters 2016年第3期27卷 467-470页

作者： zhi-Lin Cheng shuai Han College of Chemistry and Chemical Engineering Yangzhou University

For the first time the preparation of the N-doped TiO2-coated NaY zeolite membrane（N-doped TiO2/NaY zeolite membrane） as an electrode material for photoelectrocatalysis has been achieved and *** XRD, SEM, UV–vis and XPS techniques were used to characterize the structure of the N-doped TiO2/NaY zeolite membrane. The results verified that the surface of the N-doped TiO2/NaY zeolite membrane was coated by TiO2 nanoparticles of ca. 20 nm size and exhibited a distinct red-shift in the UV–vis spectra compared to N-doped TiO2. The photoelectrocatalysis performance of the N-doped TiO2/NaY zeolite membrane electrode was evaluated by phenol degradation. The results revealed it is a promising novel electrode material for application of photoelectrocatalysis in the removal of organic contaminants in waste water.

关键词： Zeolite membrane Nanocomposites Photoelectrocatalysis NaY TiO2

Inversion of the three-dimensional temperature structure of mesoscale eddies in the Northwest Pacific based on deep learning

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Acta Oceanologica Sinica 2021年第10期40卷 176-186页

作者： Fangjie Yu Zeyuan Wang shuai Liu ge Chen College of Marine Technology Faculty of Information Science and EngineeringOcean University of ChinaQingdao 266100China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China School of Marine Science and Technology Tianjin UniversityTianjin 300072China

Mesoscale eddies,which are mainly caused by baroclinic effects in the ocean,are common oceanic phenomena in the Northwest Pacific Ocean and play very important roles in ocean circulation,ocean dynamics and material energy *** temperature structure of mesoscale eddies will lead to variations in oceanic baroclinity,which can be reflected in the sea level anomaly(SLA).Deep learning can automatically extract different features of data at multiple levels without human intervention,and find the hidden relations of ***,combining satellite SLA data with deep learning is a good way to invert the temperature structure inside *** paper proposes a deep learning algorithm,eddy convolution neural network(ECN),which can train the relationship between mesoscale eddy temperature anomalies and sea level anomalies(SLAs),relying on the powerful feature extraction and learning abilities of convolutional neural *** obtaining the temperature structure model through ECN,according to climatic temperature data,the temperature structure of mesoscale eddies in the Northwest Pacific is retrieved with a spatial resolution of 0.25°at depths of 0–1000 *** overall accuracy of the ECN temperature structure is verified using Argo profiles at the locations of cyclonic and anticyclonic eddies during 2015–*** 10%error as the acceptable threshold of accuracy,89.64%and 87.25%of the cyclonic and anticyclonic eddy temperature structures obtained by ECN met the threshold,respectively.

关键词： mesoscale eddies temperature structure convolutional neural network Northwest Pacific Ocean