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αSetup-PCTL:An Adaptive Setup-Based Two-Level Preconditioner for Sequence of Linear Systems of Three-Temperature Energy Equations

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Communications in Computational Physics 2022年第10期32卷 1287-1309页

作者： Silu Huang xiaoqiang yue Xiaowen Xu Laboratory of Computational Physics Institute of Applied Physics and ComputationalMathematicsBeijing 100088China National Center for Applied Mathematics in Hunan Key Laboratory of Intelligent Computing and Information Processing of Ministry of EducationHunan Key Laboratory for Computation and Simulation in Science and EngineeringXiangtan UniversityXiangtan 411105China

The iterative solution of the sequence of linear systems arising from threetemperature(3-T)energy equations is an essential component in the numerical simulation of radiative hydrodynamic(RHD)problem.However,due to the complicated application features of the RHD problems,solving 3-T linear systems with classical preconditioned iterative techniques is challenging.To address this difficulty,a physicalvariable based coarsening two-level(PCTL)preconditioner has been proposed by dividing the fully coupled system into four individual easier-to-solve subsystems.Despite its nearly optimal complexity and robustness,the PCTL algorithm suffers from poor efficiency because of the overhead associatedwith the construction of setup phase and the solution of subsystems.Furthermore,the PCTL algorithm employs a fixed strategy for solving the sequence of 3-T linear systems,which completely ignores the dynamically and slowly changing features of these linear systems.To address these problems and to efficiently solve the sequence of 3-T linear systems,we propose an adaptive two-level preconditioner based on the PCTL algorithm,referred to as αSetup-PCTL.The adaptive strategies of the αSetup-PCTL algorithm are inspired by those of αSetup-AMG algorithm,which is an adaptive-setup-based AMG solver for sequence of sparse linear systems.The proposed αSetup-PCTL algorithm could adaptively employ the appropriate strategies for each linear system,and thus increase the overall efficiency.Numerical results demonstrate that,for 36 linear systems,the αSetup-PCTL algorithm achieves an average speedup of 2.2,and a maximum speedup of 4.2 when compared to the PCTL algorithm.

关键词： Sequence of linear systems sparse linear solver preconditioning methods radiation hydrodynamics simulation

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An Algebraic Multigrid-Based Physical Factorization Preconditioner for the Multi-Group Radiation Diffusion Equations in Three Dimensions

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Numerical Mathematics(Theory,Methods and Applications) 2023年第2期16卷 410-432页

作者： xiaoqiang yue Zekai Zhang Xiaowen Xu Shuying Zhai Shi Shu National Center for Applied Mathematics in Hunan Key Laboratory of Intelligent Computing&Information Processing of Ministry of EducationHunan Key Laboratory for Computation and Simulation in Science and EngineeringXiangtan UniversityXiangtan 411105China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100094China School of Mathematical Sciences Huaqiao UniversityQuanzhou 362021China.

The paper investigates the robustness and parallel scaling properties of a novel physical factorization preconditioner with algebraic multigrid subsolves in the iterative solution of a cell-centered finite volume discretization of the threedimensional multi-group radiation diffusion equations.The key idea is to take advantage of a particular kind of block factorization of the resulting system matrix and approximate the left-hand block matrix selectively spurred by parallel processing considerations.The spectral property of the preconditioned matrix is then analyzed.The practical strategy is considered sequentially and in parallel.Finally,numerical results illustrate the numerical robustness,computational efficiency and parallel strong and weak scalabilities over the real-world structured and unstructured coupled problems,showing its competitiveness with many existing block preconditioners.

关键词： Radiation diffusion equations physical factorization preconditioning algebraic multigrid parallel and distributed computing

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Two Physics-Based Schwarz Preconditioners for Three-Temperature Radiation Diffusion Equations in High Dimensions

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Communications in Computational Physics 2022年第8期32卷 829-849页

作者： xiaoqiang yue Jianmeng He Xiaowen Xu Shi Shu Libo Wang National Center for Applied Mathematics in Hunan Key Laboratory of Intelligent Computing&Information Processing of Ministry of EducationHunan Key Laboratory for Computation and Simulation in Science and EngineeringXiangtan UniversityXiangtan 411105P.R.China Laboratory of Computational Physics Institute of Applied Physics and ComputationalMathematicsBeijing 100094P.R.China College of Information Science and Technology JinanUniversityGuangzhou 510632P.R.China

We concentrate on the parallel,fully coupled and fully implicit solution of the sequence of 3-by-3 block-structured linear systems arising from the symmetrypreserving finite volume element discretization of the unsteady three-temperature radiation diffusion equations in high dimensions.In this article,motivated by[M.J.Gander,S.Loisel,D.B.Szyld,SIAM J.Matrix Anal.Appl.33(2012)653–680]and[S.Nardean,M.Ferronato,A.S.Abushaikha,J.Comput.Phys.442(2021)110513],we aim to develop the additive and multiplicative Schwarz preconditioners subdividing the physical quantities rather than the underlying domain,and consider their sequential and parallel implementations using a simplified explicit decoupling factor approximation and algebraic multigrid subsolves to address such linear systems.Robustness,computational efficiencies and parallel scalabilities of the proposed approaches are numerically tested in a number of representative real-world capsule implosion benchmarks.

关键词： Radiation diffusion equations Schwarz methods algebraic multigrid parallel and distributed computing

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多群辐射扩散问题特征驱动的并行AMG法

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计算物理 2024年第1期41卷 87-97页

作者：舒适岳孝强何剑萌徐小文莫则尧湘潭大学数学与计算科学学院湖南湘潭411105 北京应用物理与计算数学研究所北京100094

对求解多群辐射扩散(MGRD)方程组的大规模离散系统的已有快速算法进行分类,给出相应的综述。基于近年来所设计的关于并行代数多重网格(AMG)方面的工作,形成基于物理量的近似Schur补型与基于物理和代数特征的组合型预条件算法和理论框架... 详细信息

对求解多群辐射扩散(MGRD)方程组的大规模离散系统的已有快速算法进行分类,给出相应的综述。基于近年来所设计的关于并行代数多重网格(AMG)方面的工作,形成基于物理量的近似Schur补型与基于物理和代数特征的组合型预条件算法和理论框架,并对这些工作在该框架下的要素进行了刻画。利用上述框架,设计一种具有基本逼近性和低计算复杂度的近似Schur补型预条件子,并建立相应的谱等价理论;对比数值实验表明:新预条件子具有更好的稳健性和计算效率。最后提出需要进一步解决的若干问题。

关键词：多群辐射扩散方程组特征驱动并行代数多重网格法预条件子近似Schur补

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代谢组学在肝病中医证候研究中的应用述要

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上海中医药杂志 2024年第3期58卷 97-100页

作者：刘海亮洪靖潘波严诏贤岳小强翟笑枫上海中医药大学中西医结合学院上海201203 海军军医大学第一附属医院中医肿瘤科上海200433 海军军医大学中医系上海200433 北京大学基础医学院北京100083 海军军医大学附属长征医院中医科上海200003

证候是中医临床诊断和治疗的核心内容,是机体在疾病发展过程中某一阶段的病理概括。代谢组学可以反映机体在不同生理病理状态下代谢物水平的变化情况,其整体性、综合性、动态性等特点与中医证候的特性高度契合。通过综述代谢组学在肝癌... 详细信息

证候是中医临床诊断和治疗的核心内容,是机体在疾病发展过程中某一阶段的病理概括。代谢组学可以反映机体在不同生理病理状态下代谢物水平的变化情况,其整体性、综合性、动态性等特点与中医证候的特性高度契合。通过综述代谢组学在肝癌、肝硬化、肝炎等肝病中医证候研究中的应用情况,探讨肝病中医证候的内在机制及物质基础,助力中医客观化研究,进而指导中医临床决策。

关键词：肝癌肝硬化肝炎代谢组学中医证候研究进展

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中药青蒿抗氧化活性的谱效关系研究

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药学实践与服务 2024年第5期42卷 203-210,216页

作者：赖立勇夏天爽徐圣焱蒋益萍岳小强辛海量海军军医大学药学系生药学教研室上海200433 海军军医大学中医系上海200433 海军军医大学第二附属医院中医科上海200003

目的通过考察11批青蒿的高效液相色谱(HPLC)指纹图谱与体外抗氧化活性的谱效关系,筛选出青蒿体外抗氧化作用的药效物质基础成分。方法色谱柱为Aglient C_(18)(250 mm×4.6 mm,5μm)色谱柱,流动相为0.2%磷酸水-甲醇,流速为1 ml/min;柱温... 详细信息

目的通过考察11批青蒿的高效液相色谱(HPLC)指纹图谱与体外抗氧化活性的谱效关系,筛选出青蒿体外抗氧化作用的药效物质基础成分。方法色谱柱为Aglient C_(18)(250 mm×4.6 mm,5μm)色谱柱,流动相为0.2%磷酸水-甲醇,流速为1 ml/min;柱温为室温;检测波长为220 nm;进样量为10μl。以异绿原酸A为参照,采用《中药指纹图谱相似度评价系统》(2012版)确定并记录11批青蒿样品的共有峰。检测不同青蒿样品对DPPH自由基和ABTS自由基的清除效率,作为其抗氧化评价,利用SIMCA14.1软件构建PLSR模型并分析谱效关系。结果11批青蒿样品中共检测出48个共有峰,鉴定11个成分,分别为东莨菪内酯、滨蒿内酯、异绿原酸B、异绿原酸A、异绿原酸C、木犀草素、芹菜素、猫眼草黄素、青蒿素、艾黄素和青蒿酸。检测11批青蒿样品的DPPH自由基和ABTS自由基的清除能力,谱效关系显示,异绿原酸A、B、C和滨蒿内酯峰面积与青蒿的DPPH自由基和ABTS自由基清除能力正相关,且变量投影值大于1,表明这些成分在青蒿的体外抗氧化方面有显著贡献。结论本研究考察了青蒿中不同物质的体外抗氧化能力,证明异绿原酸A、B、C和滨蒿内酯为青蒿的体外抗氧化活性的药效物质基础。

关键词：青蒿高效液相色谱法抗氧化谱效关系药效物质基础

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胃癌前病变病证结合动物模型研究进展

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现代中医药 2024年第1期44卷 1-4页

作者：王颖矫健鹏徐晶钰刘煊王晓炜岳小强山东中医药大学山东济南250355 海军军医大学附属长征医院上海200003

中医药在胃癌前病变(precancerous lesions of gastric cancer,PLGC)诊疗中发挥着重要作用,病证结合动物模型是进行PLGC相关实验研究的前提。文章从模型动物选择、胃癌前病变疾病模型和病证结合模型三方面,对近年来PLGC病证结合模型的... 详细信息

中医药在胃癌前病变(precancerous lesions of gastric cancer,PLGC)诊疗中发挥着重要作用,病证结合动物模型是进行PLGC相关实验研究的前提。文章从模型动物选择、胃癌前病变疾病模型和病证结合模型三方面,对近年来PLGC病证结合模型的制备方法进行了归纳分析,介绍了脾胃虚弱、胃阴不足、肝胃气滞、脾胃湿热和胃络瘀血5个常见PLGC病证结合模型的造模方法,并对当前模型制备中存在的问题提出了思考与展望。

关键词：胃癌前病变动物模型病证结合慢性萎缩性胃炎

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Integrating phosphorus management and cropping technology for sustainable maize production

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Journal of Integrative Agriculture 2024年第4期23卷 1369-1380页

作者： Haiqing Gong yue Xiang Jiechen Wu Laichao Luo Xiaohui Chen xiaoqiang Jiao Chen Chen State Key Laboratory of Nutrient Use and Management College of Resources and Environmental SciencesCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China Department of Sustainable Development Environmental Science and Engineering(SEED)KTH Royal Institute of TechnologyStockholm SE-10044Sweden Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention School of Resources and EnvironmentAnhui Agricultural UniversityHefei 230036China Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering National Observations and Research Station for Wetland Ecosystems of the Yangtze EstuaryInstitute of Biodiversity Science and Institute of Eco-ChongmingCollege of Life SciencesFudan UniversityShanghai 200438China

Achieving high maize yields and efficient phosphorus(P)use with limited environmental impacts is one of the greatest challenges in sustainable maize production.Increasing plant density is considered an effective approach for achieving high maize yields.However,the low mobility of P in soils and the scarcity of natural P resources have hindered the development of methods that can simultaneously optimize P use and mitigate the P-related environmental footprint at high plant densities.In this study,meta-analysis and substance flow analysis were conducted to evaluate the effects of different types of mineral P fertilizer on maize yield at varying plant densities and assess the flow of P from rock phosphate mining to P fertilizer use for maize production in China.A significantly higher yield was obtained at higher plant densities than at lower plant densities.The application of single superphosphate,triple super-phosphate,and calcium magnesium phosphate at high plant densities resulted in higher yields and a smaller environmental footprint than the application of diammonium phosphate and monoammonium phosphate.Our scenario analyses suggest that combining the optimal P type and application rate with a high plant density could increase maize yield by 22%.Further,the P resource use efficiency throughout the P supply chain increased by 39%,whereas the P-related environmental footprint decreased by 33%.Thus,simultaneously optimizing the P type and application rate at high plant densities achieved multiple objectives during maize production,indicating that combining P management with cropping techniques is a practical approach to sustainable maize production.These findings offer strategic,synergistic options for achieving sustainable agricultural development.

关键词： maize plant density mineral phosphorus fertilizer meta-analysis substance flow analysis

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Toward quantum unmanned systems

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Science China Technological Sciences 2024年第7期67卷 2277-2280页

作者： CHENG ShuMing QI HongSheng SUN yue LIU LiJun XIE ShaoRong REN xiaoqiang Department of Control Science and Engineering Tongji University Academy of Mathematics and Systems Science Chinese Academy of Sciences Cipher Cloud Core Ltd. College of Mathematics and Computer Science Shanxi Normal University School of Computer Engineering and Science Shanghai University School of Mechatronic Engineering and Automation Shanghai University

1 Quantum information technology Quantum information technology utilizes physical systems at the microscopic level, such as photon, atom, ion, and superconducting, to accomplish information-processing tasks that are impossible for the classical macroscopic world. During the past decade, significant process has been achieved in the pursuit of quantum technology into practical applications,generating great research interest from various domains, with the potential to radically change our information infrastructure [1–3].

关键词： quantum information technology unmanned systems quantum unmanned systems

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A JASMIN-based Two-dimensional Adaptive Combined Preconditioner with Applications in Radiation Diffusion Equations

A JASMIN-based Two-dimensional Adaptive Combined Preconditio...

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2016第八届全国计算物理会议

作者： xiaoqiang yue Xiaowen Xu Shi Shu School of Mathematics and Computational Science Xiangtan University Institute of Applied Physics and Computational Mathematics

In this paper we present a JASMIN-based two-dimensional parallel implementation of an adaptive combined preconditioner Ba co,which was developed in[Commun.Comput.Phys.,18（5）（2015）:1313-1335],for the solution of linear problems corresponding to the finite volume discretization of one-and multi-group radiation diffusion equations.We firstly propose the attribute of patch-correlation for cells of two-dimensional monolayer piecewise rectangular structured grid without any suspensions based on the patch hierarchy of JASMIN,classify and reorder these cells via their attributes,and derive the conversion of cell-permutations.Using the two cell-permutations,we next construct parallel incomplete LU factorization and substitution algorithras,and provide the parallel Ba co-GMRES solver with the help of the default BoomerAMG in HYPRE library.Numerical results demonstrate that our proposed parallel incomplete LU preconditioner is of higher efficiency than the one in Euclid library,and the proposed parallel Ba co-GMRES solver is more robust and more efficient than the default BoomerAMG-GMRES solver.

关键词： Radiation diffusion equations combined preconditioner adaptive technology parallel computing JASMIN

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