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光滑核紧积分算子特征值的多尺度Galerkin快速算法

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中山大学学报（自然科学版） 2011年第3期50卷 27-30,34页

作者：陈剑曾泰山佛山科学技术学院理学院数学系广东佛山528000 华南师范大学数学科学学院广东广州510631

考虑一类积分算子特征值问题的多尺度Galerkin逼近格式,给出了相应的截断策略,大大减少了计算量,证明了收敛阶和计算复杂度达到几乎最优。

关键词：紧算子特征值多尺度Galerkin算法

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时间分数阶次扩散方程的多层扩充算法

华南师范大学学报（自然科学版） 2020年第3期52卷 106-110页

作者：陈剑曾泰山佛山科学技术学院数学与大数据学院佛山528000 华南师范大学数学科学学院广州510631

基于L1公式和多尺度Galerkin方法,对具有α阶Caputo导数的时间分数阶次扩散方程建立了全离散格式;证明了全离散格式存在唯一解和具有最优收敛阶O(hr+2-α),r为分片多项式的次数;在每个时间层,对全离散格式所得线性方程组,设计了多层扩... 详细信息

基于L1公式和多尺度Galerkin方法,对具有α阶Caputo导数的时间分数阶次扩散方程建立了全离散格式;证明了全离散格式存在唯一解和具有最优收敛阶O(hr+2-α),r为分片多项式的次数;在每个时间层,对全离散格式所得线性方程组,设计了多层扩充算法进行高效求解,并保持着最优收敛阶;最后,给出数值算例来验证理论分析的正确性.

关键词： L1逼近多尺度正交基多层扩充法分数阶次扩散方程收敛阶

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多尺度全变差图像去噪算法

华南师范大学学报（自然科学版） 2013年第4期45卷 42-44页

作者：曾泰山鲁春元华南师范大学数学科学学院广东广州510631 广东药学院医药信息工程学院广东广州510006

结合小波和全变差方法,提出了一种多尺度全变差去噪算法.该算法结合了小波的多尺度结构,并通过对多层小波分解后的高低频施加不同的正则化参数,在频率域上实行多尺度全变差去噪.实验结果证明,所提出的算法相对于全变差去噪方法和小波去... 详细信息

结合小波和全变差方法,提出了一种多尺度全变差去噪算法.该算法结合了小波的多尺度结构,并通过对多层小波分解后的高低频施加不同的正则化参数,在频率域上实行多尺度全变差去噪.实验结果证明,所提出的算法相对于全变差去噪方法和小波去噪方法,能够更好地抑制噪声、保持边缘和消除阶梯效应.

关键词：图像去噪全变差模型多尺度保边缘

求解大规模线性时不变系统的最优H_2模型降阶问题的共轭梯度法

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中山大学学报（自然科学版） 2011年第2期50卷 1-5页

作者：曾泰山鲁春元陈剑中山大学数学与计算科学学院广东广州510275 广东药学院医药信息工程学院广东广州510006 佛山科学技术学院数学系广东佛山528000

针对最优H2模型降阶问题,提出了适合大规模多输入多输出系统的共轭梯度法。该方法仅需利用一阶导数信息,存储量少,计算复杂度低,且具有超线性收敛性。实验结果显示了算法的有效性。

关键词：模型降阶共轭梯度法 Grassmann流形线性时+不变系统

二维Helmholtz方程的改进六阶紧致差分法

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华南师范大学学报（自然科学版） 2022年第2期54卷 90-100页

作者：王肇君吴亭亭曾泰山山东师范大学数学与统计学院济南250358 华南师范大学数学科学学院广州510631 广东省大数据分析与处理重点实验室广州510006

为得到求解二维Helmholtz方程的高精度差分法,构造了一种改进六阶紧致差分格式:首先,给出一种带优化参数的六阶紧致差分格式的截断误差;然后,对此截断误差的部分项进行二阶紧致逼近,得到一种改进紧致差分格式;其次,对该格式进行了收敛... 详细信息

为得到求解二维Helmholtz方程的高精度差分法,构造了一种改进六阶紧致差分格式:首先,给出一种带优化参数的六阶紧致差分格式的截断误差;然后,对此截断误差的部分项进行二阶紧致逼近,得到一种改进紧致差分格式;其次,对该格式进行了收敛性分析,证明其为六阶收敛的;最后,基于极小化数值频散的思想,给出该格式优化参数的加细选取策略。与带优化参数的六阶紧致差分格式相比,数值实验说明改进六阶紧致差分格式的数值精度有了显著提高,且其误差对波数k的依赖性更低。

关键词： Helmholtz方程紧致差分格式数值频散

Data Quality Control Method of a New Drifting Observation Technology Named Drifting Air-Sea Interface Buoy

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Journal of Ocean University of China 2024年第1期23卷 11-22页

作者： LI Shuo WANG Bin DENG zeng’an WU Baoqin ZHU Xiande CHEN Zhaohui National Ocean Technology Center Tianjin 300112China School of Marine Science and Technology Tianjin UniversityTianjin 300072China Key Laboratory of Ocean Observation Technology Ministry of Natural ResourcesTianjin 300112China People’s Liberation Army 92859 Tianjin 300061China Physical Oceanography Laboratory Ocean University of ChinaQingdao 266100China

An integral quality control(QC)procedure that integrates various QC methods and considers the design indexes and operational status of the instruments for the observations of drifting air-sea interface buoy was developed in the order of basic in-spection followed by targeted *** innovative method of combining a moving Hampel filter and local anomaly detection com-plies with statistical laws and physical processes,which guarantees the QC performance of meteorological *** sets of observation data were used to verify the applicability and effectiveness of the QC procedure,and the effect was evaluated using the observations of the Kuroshio Extension Observatory buoy as the *** results showed that the outliers in the time series can be correctly identified and processed,and the quality of data improved *** linear correlation between the quality-controlled observations and the reference increased,and the difference *** correlation coefficient of wind speed before and after QC increased from 0.77 to 0.82,and the maximum absolute error decreased by approximately 2.8ms^(-1).In addition,air pressure and relative humidity were optimized by 10^(-3)–10^(-2) orders of *** the sea surface temperature,the weight of coefficients of the continuity test algorithm was optimized based on the sea area of data acquisition,which effectively expanded the applicability of the algorithm.

关键词： drifting air-sea interface buoy quality control oceanic variables meteorological variables continuity test

The Performance of Downward Shortwave Radiation Products from Satellite and Reanalysis over the Transect of Zhongshan Station to Dome A, East Antarctica

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Advances in Atmospheric Sciences 2024年第8期41卷 1574-1588,1671-1675页

作者： Jiajia JIA Zhaoliang zeng Wenqian ZHANG Xiangdong ZHENG Yaqiang WANG Minghu DING State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China

The downward shortwave radiation(DSR) is an important part of the Earth's energy balance, driving Earth's system's energy, water, and carbon cycles. Due to the harsh Antarctic environment, the accuracy of DSR derived from satellite and reanalysis has not been systematically evaluated over the transect of Zhongshan station to Dome A, East ***, this study aims to evaluate DSR reanalysis products(ERA5-Land, ERA5, MERRA-2) and satellite products(CERES and ICDR) in this area. The results indicate that DSR exhibits obvious monthly and seasonal variations, with higher values in summer than in winter. The ERA5-Land(ICDR) DSR product demonstrated the highest(lowest) accuracy,as evidenced by a correlation coefficient of 0.988(0.918), a root-mean-square error of 23.919(69.383) W m^(–2), a mean bias of –1.667(–28.223) W m^(–2) and a mean absolute error of 13.37(58.99) W m^(–2). The RMSE values for the ERA5-Land reanalysis product at seven stations, namely Zhongshan, Panda 100, Panda 300, Panda 400, taishan, Panda 1100, and Kunlun, were 30.938, 29.447, 34.507, 29.110, 20.339, 17.267, and 14.700 W m^(-2), respectively;with corresponding bias values of 9.887, –12.159, –19.181, –15.519, –8.118, 6.297, and 3.482 W m^(–2). Regarding seasonality, ERA5-Land, ERA5,and MERRA-2 reanalysis products demonstrate higher accuracies during spring and summer, while ICDR products are least accurate in autumn. Cloud cover, water vapor, total ozone, and severe weather are the main factors affecting DSR. The error of DSR products is greatest in coastal areas(particularly at the Zhongshan station) and decreases towards the inland areas of Antarctica.

关键词： downward shortwave radiation East Antarctic reanalysis product satellite product validation

Au-Fe_(3)O_(4) dumbbell-like nanoparticles based lateral flow immunoassay for colorimetric and photothermal dual-mode detection of SARS-CoV-2 spike protein

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Chinese Chemical Letters 2024年第6期35卷 536-540页

作者： Gengchen Guo Tianyu Zhao Ruichang Sun Mingzhe Song Hongyu Liu Sen Wang Jingwen Li Jingbin zeng College of Chemistry and Chemical Engineering and State Key Laboratory of heavy oil processing China University of Petroleum(East China)Qingdao 266580China Huangdao Customs of the People’s Republic of China Qingdao 266580China

Lateral flow immunoassay(LFIA)has become popular in laboratories,at-home testing,and medical diagnostics due to its minimal cost and ***,conventional test strips based on colloidal gold can only obtain qualitative or semi-quantitative results with low *** this work,AuFe_(3)O_(4) dumbbell-like nanoparticles were synthesized and used as the LFIA labelling marker for highly sensitive colorimetric-photothermal dual-mode detection of SARS-CoV-2 spike(S)*** unique dumbbell structure of Au-Fe_(3)O_(4) NPs makes it possible to combine the best features of both Au NPs and Fe_(3)O_(4) *** increased surface area of these NPs enhances their LSPR effect and photothermal effect,which achieves signal amplification to increase *** Au-Fe_(3)O_(4) NPs modified with S protein antibody could identify S protein in samples,which were recognized and accumulated on T-line by another antibody,generating color band for qualitative colorimetric *** T-line was irradiated by laser to obtain temperature change for quantitative detection of *** optimized conditions,the detection limit was 1.22 pg/m L,three orders of magnitude more sensitive than colorimetric ***,the approach was performed on SARS-CoV-2 pseudovirus samples and outperformed traditional colloidal gold *** LFIA platform exhibits significant promise for practical implementation,as it can satisfy the need for low-cost,high-sensitivity,and home-based quantitative detection for respiratory infectious diseases.

关键词： Au-Fe_(3)O_(4) dumbbell-like nanoparticles Photothermal effect LFIA S protein

Enhanced optical imaging and fluorescent labeling for visualizing drug molecules within living organisms

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2428-2446页

作者： Ting Sun Huanxin Zhao Luyao Hu Xintian Shao Zhiyuan Lu Yuli Wang Peixue Ling Yubo Li Kewu zeng Qixin Chen School of Pharmaceutical Sciences National Key Laboratory of Advanced Drug Delivery SystemMedical Science and Technology Innovation CenterShandong First Medical University&Shandong Academy of Medical SciencesJinan 250062China Departments of Diagnostic Radiology SurgeryChemical and Biomolecular Engineeringand Biomedical EngineeringYong Loo Lin School of Medicine and College of Design and EngineeringNational University of SingaporeSingapore 119074Singapore Institute of Biochemical and Biotechnological Drugs School of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityJinan 250012China Key Laboratory of Biopharmaceuticals Postdoctoral Scientific Research WorkstationShandong Academy of Pharmaceutical ScienceJinan 250098China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China School of Life Sciences Science and Technology Innovation CenterShandong First Medical University&Shandong Academy of Medical SciencesJinan 250062China School of Chinese Materia Medica Tianjin University of Traditional Chinese MedicineTianjin 301617China Tianjin Pharmaceutical DA REN TANG Group Corporation Limited Traditional Chinese Pharmacy Research Institute Tianjin 300457China Key Laboratory of Systems Bioengineering(Ministry of Education) School of Chemistry Engineering and TechnologyTianjin UniversityTianjin 300072China

The visualization of drugs in living systems has become key techniques in modern *** advancements in optical imaging technologies and molecular design strategies have revolutionized drug *** the subcellular level,super-resolution microscopy has allowed exploration of the molecular landscape within individual cells and the cellular response to *** beyond subcellular imaging,researchers have integrated multiple modes,like optical near-infrared II imaging,to study the complex spatiotemporal interactions between drugs and their *** combining these visualization approaches,researchers gain supplementary information on physiological parameters,metabolic activity,and tissue composition,leading to a comprehensive understanding of drug *** review focuses on cutting-edge technologies in drug visualization,particularly fluorescence imaging,and the main types of fluorescent molecules ***,we discuss current challenges and prospects in targeted drug research,emphasizing the importance of multidisciplinary cooperation in advancing drug *** the integration of advanced imaging technology and molecular design,drug visualization has the potential to redefine our understanding of pharmacology,enabling the analysis of drug micro-dynamics in subcellular environments from new perspectives and deepening pharmacological research to the levels of the cell and organelles.

关键词： Optical imaging Drug visualization Fluorophore labeling Therapeutics