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Numerical simulation of a complex moving rigid body under the impingement of a shock wave in 3D

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Advances in Aerodynamics 2022年第1期4卷 147-175页

作者： Shihao Liu Ziqiang Cheng Yan Jiang jianfang lu Mengping Zhang Shuhai Zhang School of Mathematical Sciences University of Science and Technology of ChinaHefei230026AnhuiChina School of Mathematics Hefei University of TechnologyHefei230000AnhuiChina School of Mathematics South China University of TechnologyGuangzhou510641GuangdongChina State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang621000SichuanChina

In this paper,we take a numerical simulation of a complex moving rigid body under the impingement of a shock wave in three-dimensional space.Both compressible inviscid fluid and viscous fluid are considered with suitable boundary conditions.We develop a high order numerical boundary treatment for the complex moving geometries based on finite difference methods on fixed Cartesian meshes.The method is an extension of the inverse Lax-Wendroff(ILW)procedure in our works(Cheng et al.,Appl Math Mech(Engl Ed)42:841-854,2021;Liu et al.)for 2D problems.Different from the 2D case,the local coordinate rotation in 3D required in the ILW procedure is not unique.We give a theoretical analysis to show that the boundary treatment is independent of the choice of the rotation,ensuring the method is feasible and valid.Both translation and rotation of the body are taken into account in this paper.In particular,we reformulate the material derivative for inviscid fluid on the moving boundary with no-penetration condition,which plays a key role in the proposed algorithm.Numerical simulations on the cylinder and sphere are given,demonstrating the good performance of our numerical boundary treatments.

关键词： Inverse Lax-Wendroff procedure High order accuracy Complex moving boundary treatment Compressible inviscid fluid Compressible viscous fluid 3D

A Discontinuous Galerkin Method with Penalty for One-Dimensional Nonlocal Diffusion Problems

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Communications on Applied Mathematics and Computation 2020年第1期2卷 31-55页

作者： Qiang Du Lili Ju jianfang lu Xiaochuan Tian Department of Applied Physics and Applied Mathematics Columbia UniversityNew YorkNY 10027USA Department of Mathematics University of South CarolinaColumbiaSC 29208USA South China Research Center for Applied Mathematics and Interdisciplinary Studies South China Normal UniversityGuangzhou 510631China Department of Mathematics University of Texas at AustinAustinTX 78712USA

There have been many theoretical studies and numerical investigations of nonlocal diffusion(ND)problems in recent years.In this paper,we propose and analyze a new discontinuous Galerkin method for solving one-dimensional steady-state and time-dependent ND problems,based on a formulation that directly penalizes the jumps across the element interfaces in the nonlocal sense.We show that the proposed discontinuous Galerkin scheme is stable and convergent.Moreover,the local limit of such DG scheme recovers classical DG scheme for the corresponding local diff usion problem,which is a distinct feature of the new formulation and assures the asymptotic compatibility of the discretization.Numerical tests are also presented to demonstrate the eff ectiveness and the robustness of the proposed method.

关键词： Nonlocal diff usion Discontinuous Galerkin method Interior penalty Asymptotic compatibility Strong stability preserving

区域协调发展与交通强国建设--全国经济地理研究会第二十六届年会综述

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区域经济评论 2024年第2期 156-160页

作者：李鲁李剑芳首都经济贸易大学城市经济与公共管理学院北京100070 南京农业大学经济管理学院南京210095

2023年10月28日,第二十六届全国经济地理研究会在湖南长沙举办。年会以“深入实施区域协调发展战略和加快建设交通强国”为主题展开研讨,与会专家围绕区域经济协调发展与区域重大战略、区域经济发展与交通强国建设、长江经济带高质量发... 详细信息

2023年10月28日,第二十六届全国经济地理研究会在湖南长沙举办。年会以“深入实施区域协调发展战略和加快建设交通强国”为主题展开研讨,与会专家围绕区域经济协调发展与区域重大战略、区域经济发展与交通强国建设、长江经济带高质量发展、区域发展与经济韧性、数字经济与碳排放、区域经济发展的热点问题等进行深入交流,为中国区域经济地理的发展提供了新颖的研究视角,并提出了相关对策建议。

关键词：经济地理区域协调发展交通强国区域韧性

A high order boundary scheme to simulate complex moving rigid body under impingement of shock wave

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Applied Mathematics and Mechanics(English Edition) 2021年第6期42卷 841-854页

作者： Ziqiang CHENG Shibao LIU Yan JIANG jianfang lu Mengping ZHANG Shuhai ZHANG School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China South China Research Center for Applied Mathematics and Interdisciplinary Studies South China Normal UniversityGuangzhou 510631Chins State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000Sichuan ProvinceChina

In the paper, we study a high order numerical boundary scheme for solving the complex moving boundary problem on a fixed Cartesian mesh, and numerically investigate the moving rigid body with the complex boundary under the impingement of an inviscid shock wave. Based on the high order inverse Lax-Wendroff(ILW) procedure developed in the previous work(TAN, S. and SHU, C. W. A high order moving boundary treatment for compressible inviscid flows. Journal of Computational Physics, 230(15),6023–6036(2011)), in which the authors only considered the translation of the rigid body,we consider both translation and rotation of the body in this paper. In particular, we reformulate the material derivative on the moving boundary with no-penetration condition, and the newly obtained formula plays a key role in the proposed algorithm. Several numerical examples, including cylinder, elliptic cylinder, and NACA0012 airfoil, are given to indicate the effectiveness and robustness of the present method.

关键词： inverse Lax-Wendroff(ILW)procedure complex moving boundary scheme Cartesian mesh high order accuracy compressible inviscid shock wave

养殖户对强制免疫“先打后补”政策满意度及影响因素分析

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中国农业大学学报 2024年第3期29卷 274-286页

作者：周勋章李建芳李增友常芳楠丛林路剑河北农业大学经济管理学院河北保定071000 河北省农业农村厅石家庄050035

为探究养殖户对强制免疫“先打后补”政策的满意度及影响因素,以重大动物疫病强制免疫“先打后补”政策试点省份之一的河北省生猪产业为例,基于1 115份生猪养殖户调研数据,借助顾客满意度(CSI)模型,构建养殖户强制免疫政策满意度理论分... 详细信息

为探究养殖户对强制免疫“先打后补”政策的满意度及影响因素,以重大动物疫病强制免疫“先打后补”政策试点省份之一的河北省生猪产业为例,基于1 115份生猪养殖户调研数据,借助顾客满意度(CSI)模型,构建养殖户强制免疫政策满意度理论分析框架,运用多元有序Logistic、多元有序Probit和Heckman模型,深入研究了养殖户对强制免疫“先打后补”政策满意度评价的影响因素。结果表明:1)当前我国强制免疫补贴政策的规制作用大于激励作用。2)养殖户强制免疫政策满意度评价受到多种因素影响,且不同规模养殖户强制免疫政策满意度评价影响因素存在一定差异。鉴于此,要提高养殖户对强制免疫“先打后补”政策认知水平,完善强制免疫政策的规制和激励机制,提高养殖户组织化程度和创新“先打后补”政策宣传方式。

关键词：强制免疫 “先打后补”政策顾客满意度模型生猪产业影响因素

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男性血液透析患者性功能障碍现状及影响因素

中国男科学杂志 2024年第3期38卷 70-74页

作者：吴陆飞周建芳陆晓艳胡婷杭州市中医院血透室

目的调查男性血液透析患者性功能障碍现状及其影响因素，为提高男性血液透析患者生活质量提供依据。方法选取2022年5月至2023年5月在我院接受规律性、维持性血液透析治疗的102例男性患者作为研究对象，应用一般资料调查表、汉密尔顿... 详细信息

目的调查男性血液透析患者性功能障碍现状及其影响因素，为提高男性血液透析患者生活质量提供依据。方法选取2022年5月至2023年5月在我院接受规律性、维持性血液透析治疗的102例男性患者作为研究对象，应用一般资料调查表、汉密尔顿抑郁量表、国际勃起功能指数-5量表为调查工具进行问卷调查，采用单因素分析、有序Logistic回归分析男性血液透析患者勃起功能指数的影响因素。结果勃起功能正常患者7例，轻度障碍25例，中度障碍16例，重度障碍54例；对不同程度勃起障碍患者年龄、血清肌酐、血清尿酸、抑郁指数等进行对比，有统计学差异(P<0.05);有序Logistic回归分析结果显示，抑郁指数(OR=1.39)、年龄(OR=1.14)、文化程度(OR=7.29)、睡眠时间(OR=32.84)、工作状态(OR=0.08)是男性血液透析患者勃起功能障碍的影响因素(P<0.05)。结论男性血液透析患者勃起功能障碍发生率较高，且以中重度为多。抑郁、年龄、文化程度、睡眠时间及工作状态为勃起功能障碍的独立影响因素，临床应针对抑郁、年龄、文化程度、睡眠时间等因素采取相关措施，以降低其发生率，提高患者生活质量。

关键词：肾透析男性性功能障碍影响因素分析

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基因重配对B型流感病毒生长特性的影响

中国生物制品学杂志 2024年第4期37卷 426-432页

作者：张瑶周剑芳鲁健李希妍曾晓旭王大燕北京市东城区疾病预防控制中心检验科北京100050 中国疾病预防控制中心病毒病预防控制所世界卫生组织流感参比和研究合作中心北京102206

目的利用反向遗传学方法研究流感病毒各基因节段对其生长特性的影响。方法挑选系间重配病毒B/福建同安/1565/2013及B/北京怀柔/11764/2013进行生长曲线测定。提取病毒核酸,扩增病毒各基因节段,并利用pHW2000载体构建重组质粒。对构建... 详细信息

目的利用反向遗传学方法研究流感病毒各基因节段对其生长特性的影响。方法挑选系间重配病毒B/福建同安/1565/2013及B/北京怀柔/11764/2013进行生长曲线测定。提取病毒核酸,扩增病毒各基因节段,并利用pHW2000载体构建重组质粒。对构建的重组质粒在两病毒间进行单一及不同组合基因节段的替换后,构建新的重配病毒,检测重配病毒的生长特性,推测基因节段的影响作用。结果 2株系间重配病毒生长特性差异显著,B/福建同安/1565/2013比B/北京怀柔/11764/2013生长曲线的峰值点高约2倍log值,但将B/北京怀柔/11764/2013单一节段分别替换至B/福建同安/1565/2013重配出的8株病毒与B/福建同安/1565/2013的生长特性差异不明显,而在同时替换HA和NA(表面蛋白)或PB2、PB1和PA(聚合酶)或PB2、PB1、PA和NP(核糖核蛋白,RNP)3种基因组合时,重配病毒的生长特性下降显著。结论 B型流感病毒生长特性受单一节段影响可能性较小,多个节段的协同作用对其影响更为显著,在监测过程中应加强对重配变异病毒的监测。

关键词： B型流感病毒基因重配反向遗传生长特性

Roles of Multisourced Fluids in the Formation of Sandstone-Hosted Uranium Deposits in the SW Songliao Basin, NE China

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Journal of Earth Science 2023年第1期34卷 54-69页

作者： Zhibing Feng Fengjun Nie Li Jiang Fei Xia jianfang Cai Bocheng Zhang Yayun lu Liangliang Zhang State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang330013China Jiangxi Engineering Laboratory on Radioactive Geoscience and Big Data Technology East China University of TechnologyNanchang330013China Radioactive Geology and Exploration Technology Laboratory East China University of TechnologyNanchang330013China No.243 Geological Party China National Nuclear CorporationChifeng024000China Airborne Survey and Remote Sensing Center of Nuclear Industry China National Nuclear CorporationShijiazhuang050002China

The sandstone-hosted uranium deposits in the SW Songliao Basin differ from typical sandstone-hosted uranium deposits in terms of the geological features of the ore-deposits,including the geometry of the orebodies,mineral assemblage and petrography.Detailed drill core and microscopic observations,scanning electron microscopy(SEM),electron microprobe analysis(EMPA),heavy mineral concentrates,and fluid inclusion studies of the Upper Cretaceous Yaojia Formation,i.e.,the uranium-bearing layer,were integrated to investigate the roles of hydrothermal fluids in the formation of these uranium deposits.We found that the kaolinite alteration is developed in the mineralized zones,but it is less common in the peripheral areas.The fluid inclusions are hydrothermal fluids with a medium-low temperature(67 to 179 ℃) and a high salinity(5.9 wt.% to 20.1 wt.%).According to the analyses,three kinds of hydrothermal fluids,i.e.,the acid fluid,the groundwater heated by the mafic magma,and the alkaline fluid rich in Ca^(2+) and CO_(3)^(2-),were identified.The fluids might have low U content,but they have participated in the formation of the uranium deposits successively.Kaolinite formed by the acid-hydrothermal fluid absorbed large amounts of uranium.Subsequently,the thermal energy from the hydrothermal fluids changed the intrastratal redox environment and increased the solubility of the uranium minerals in the fluid.The alkaline-hydrothermal fluid rich in Ca^(2+) and C0_(3)^(2-) facilitated the formation of stable Ca-U(Ⅵ)-CO_(3) complex,which led to the enrichment of soluble uranium in solution,and final precipitation as pitchblende,brannerite and Ti-bearing uranium minerals in the uranium ores.

关键词： sandstone-hosted uranium deposit hydrothermal fluid uranium mineralization Songliao Basin kaolinite carbonate minerals

赤道印度洋中部沉降颗粒物的季节变化特征及调控机制研究

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应用海洋学学报 2024年第2期43卷 324-332页

作者：余锦萍张静静李宏亮卢阳阳何兴举武则州陈建芳自然资源部第二海洋研究所、自然资源部海洋生态系统动力学重点实验室浙江杭州310012

基于2020年1—12月在赤道印度洋中部海域获取的沉积物捕获器时间序列样品,分析了沉降颗粒物与颗粒有机碳(particulate organic carbon,POC)通量的季节变化特征,并结合卫星遥感、数值模式及再分析数据探究上层物理过程对生物泵输出通量... 详细信息

基于2020年1—12月在赤道印度洋中部海域获取的沉积物捕获器时间序列样品,分析了沉降颗粒物与颗粒有机碳(particulate organic carbon,POC)通量的季节变化特征,并结合卫星遥感、数值模式及再分析数据探究上层物理过程对生物泵输出通量的调控作用。结果表明,2020年赤道印度洋中部海域的沉降颗粒物总通量与颗粒有机碳通量的变化范围分别为4.57~35.75 mg/(m^(2)·d)[(18.94±10.18)mg/(m^(2)·d)]和0.27~2.97 mg/(m^(2)·d)[(1.09±0.66)mg/(m^(2)·d)],两者均呈现显著的季节变化特征。总体上,1—3月、6月和9—11月呈现出3个显著的高通量事件。通过分析发现混合层深度变化与营养盐跃层波动的耦合作用可能是调控中深层通量变化的主要原因。与此同时,西南季风流(Southwest Monsoon Current,SMC)与赤道Wyrtki急流生消也可能通过改变温跃层或营养盐跃层深度对沉降颗粒物通量强度和季节变化起调控作用。

关键词：海洋化学沉降颗粒物沉积物捕获器混合层温跃层赤道印度洋