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Trace formula of the integro-differential operator on a quantum graph

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applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 311-318页

作者： WEI Li-xiao YANG Chuan-fu school of Mathematics and Statistics Nanjing University of Science and TechnologyNanjing 210094China.

In this paper we study the eigenvalue problem for integro-differential operators on a lasso *** trace formula of the operator is established by applying the residual technique in complex analysis.

关键词： integro-differential operators eigenvalue trace formula

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将混沌序列变换成均匀伪随机序列的普适算法

物理学报 2008年第7期57卷 4007-4013页

作者：盛利元肖燕予盛喆中南大学物理科学与技术学院长沙410083 Department of applied Mathematics science College University of Western Ontario London ON Canada N6A 5B7 中南大学数学与统计学院长沙410075

提出了一种将混沌序列变换成均匀伪随机序列的普适算法.这种算法基于计算机浮点数表示的bit位操作,不针对任何具体对象,可将任意连续或分段连续分布的实型随机变量转换成均匀分布的随机变量.理论分析表明,这种算法源于实型随机变量中普... 详细信息

提出了一种将混沌序列变换成均匀伪随机序列的普适算法.这种算法基于计算机浮点数表示的bit位操作,不针对任何具体对象,可将任意连续或分段连续分布的实型随机变量转换成均匀分布的随机变量.理论分析表明,这种算法源于实型随机变量中普遍存在着的沿bit位以指数规律增强的均匀化趋势.任何实型的混沌序列,不论来自混沌映射系统还是混沌微分动力系统,都可以在同一个标准算法下变换成均匀分布的伪随机序列,因而是混沌伪随机数发生器标准化模块设计和硬件实现的关键技术基础.

关键词：混沌伪随机序列均匀分布函数

A CELL-CENTERED GODUNOV METHOD BASED ON STAGGERED DATA DISTRIBUTION,PART Ⅰ:ONE-DIMENSIONAL CASE

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Journal of Computational Mathematics 2024年第4期42卷 1172-1196页

作者： Jiayin Zhai xiao Li Zhijun Shen Institute of applied Physics and Computational Mathematics LCPP.O.Box 8009-26Beijing 100088China College of Big Data and Internet Shenzhen Technology UniversityShenzhen 518118China Center for applied Physics and technology HEDPSPeking UniversityChina

This paper presents a cell-centered Godunov method based on staggered data distribu-tion in Eulerian *** motivation is to reduce the intrinsic entropy dissipation of classical Godunov methods in the calculation of an isentropic or rarefaction *** the same time,the property of accurate shock capturing is also *** analyzing the factors that cause nonphysical entropy in the conventional Godunov methods,we introduce two velocities rather than a single velocity in a cell to reduce kinetic energy dissipation.A series of redistribution strategies are adopted to update subcell quantities in order to improve *** examples validate that the present method can dramatically reduce nonphysical entropy *** subject classification:3.Q3.,76N15,76M12.

关键词： Godunov method Riemann solver Rarefaction wave Nonphysical entropy increase.

Resilience assessment and optimization method of city road network in the post-earthquake emergency period

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 765-779页

作者： Wang Haoran xiao Jia Li Shuang Zhai Changhai Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information TechnologyHarbin Institute of TechnologyHarbin 150090China

The post-earthquake emergency period,which is a sensitive time segment just after an event,mainly focuses on saving life and restoring social *** improve the seismic resilience of city road networks,a resilience evaluation method used in the post-earthquake emergency period is *** road seismic damage index of a city road network can consider the influence of roads,bridges and buildings along the roads,*** road capacity after an earthquake.A function index for a city road network is developed,which reflects the connectivity,redundancy,traffic demand and traffic function of the *** optimization model for improving the road repair order in the post-earthquake emergency period is also developed according to the resilience evaluation,to enable decision support for city emergency management and achieve the best seismic resilience of the city road *** optimization model is applied to a city road network and the results illustrate the feasibility of the resilience evaluation and optimization method for a city road network in the post-earthquake emergency period.

关键词： city road network post-earthquake emergency period traffic demand resilience evaluation optimization model

Investigation of high rate mechanical flow followed by ignition for high-energy propellant under dynamic extrusion loading

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Defence technology（防务技术） 2024年第2期32卷 336-347页

作者： Liying Dong Yanqing Wu Kun Yang xiao Hou State Key Laboratory of Explosion science and technology Beijing Institute of TechnologyBeijing 100081China school of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

Investigating the ignition response of nitrate ester plasticized polyether(NEPE) propellant under dynamic extrusion loading is of great significant at least for two cases. Firstly, it helps to understand the mechanism and conditions of unwanted ignition inside charged propellant under accident ***, evaluates the risk of a shell crevice in a solid rocket motor(SRM) under a falling or overturning scene. In the present study, an innovative visual crevice extrusion experiment is designed using a dropweight apparatus. The dynamic responses of NEPE propellant during extrusion loading, including compaction and compression, rapid shear flow into the crevice, stress concentration, and ignition reaction, have been firstly observed using a high-performance high-speed camera. The ignition reaction is observed in the triangular region of the NEPE propellant sample above the crevice when the drop weight velocity was 1.90 m/s. Based on the user material subroutine interface UMAT provided by finite element software LS-DYNA, a viscoelastic-plastic model and dual ignition criterion related to plastic shear dissipation are developed and applied to the local ignition response analysis under crevice extrusion conditions. The stress concentration occurs in the crevice location of the propellant sample, the shear stress is relatively large, the effective plastic work is relatively large, and the ignition reaction is easy to occur. When the sample thickness decreases from 5 mm to 2.5 mm, the shear stress increases from 22.3.MPa to 28.6 MPa, the critical value of effective plastic work required for ignition is shortened from 1280 μs to 73. μs, and the triangular area is easily triggering an ignition reaction. The propellant sample with a small thickness is more likely to stress concentration, resulting in large shear stress and effective work, triggering an ignition reaction.

关键词： NEPE propellant Crevice extrusion Shear flow Sample thickness Ignition reaction

Exploring the Pathogenesis of Autoimmune Liver Diseases from the Heterogeneity of Target Cells

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Journal of Clinical and Translational Hepatology 2024年第7期12卷 659-666页

作者： Zi-Xuan Qiu Lin-Xiang Huang xiao-xiao Wang Zi-Long Wang xiao-He Li Bo Feng Peking university People’s Hospital Peking University Hepatology InstituteBeijing Key Laboratory of Hepatitis C and Immunotherapy for Liver DiseasesBeijing International Cooperation Base for Science and Technology on NAFLD DiagnosisBeijingChina

The incidence of autoimmune liver diseases(ALDs)and research on their pathogenesis are increasing ***,except for autoimmune hepatitis,which responds well to immunosuppression,primary biliary cholangitis and primary sclerosing cholangitis are insensitive to immunosuppressive *** the known effects of the environment,genetics,and immunity on ALDs,the heterogeneity of target cells provides new insights into their *** review started by exploring the heterogeneity in the development,structures,and functions of hepatocytes and epithelial cells of the small and large bile *** example,cytokeratin(CK)8 and CK18 are primarily expressed in hepatocytes,while CK7 and CK19 are primarily expressed in intrahepatic ***,emerging technologies of single-cell RNA sequencing and spatial transcriptomic are being applied to study *** review offered a new perspective on understanding the pathogenic mechanisms and potential treatment strategies for ALDs.

关键词： Autoimmune hepatitis Primary biliary cholangitis Primary sclerosing cholangitis Disease heterogeneity Single-cell RNA sequencing Pathogenesis

Statistical assessment of H/A target decomposition theorems in radar polarimetry

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science China(Information sciences) 2010年第2期53卷 355-366页

作者： LIU Tao 1,2 , HUANG GaoMing 1 , WANG XueSong 2 & xiao ShunPing 2 1 school of Electronic Engineering, Naval university of Engineering, Wuhan 43.03., China 2 school of Electronic science and Engineering, National university of Defense technology, Changsha 410073. China 1. school of Electronic Engineering Naval University of Engineering Wuhan 430033 China2. School of Electronic Science and Engineering National University of Defense Technology Changsha 410073 China

Target decomposition (TD) theorems have been widely applied in radar polarimetry, serving as the bridge between radar measurements and the physical parameters of a scatterer. The H/A target decomposition is one of the most suitable tools for performing data interpretation in the study and characterization of natural scatters. In this paper, the statistics of the parameters of eigenvalue, eigenvector and H/A have been analyzed via a novel method, and the probability density functions (PDF) have been obtained. It is pointed out that all these parameters can be seen as asymptotically nonbiased with respect to the number of looks. In order to reduce the biases for a small number of looks, a novel estimator for the parameters has been proposed. We give the basic theorems for accurate estimation of parameters.

关键词： target decomposition theorems H/A characteristic parameters statistical analysis MLE

Uniqueness on Difference Operators of Meromorphic Functions of Infinite Order

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Acta Mathematica Sinica,English Series 2024年第2期40卷 511-527页

作者： Hui LI Ming Liang FANG xiao YAO school of science China University of Mining and TechnologyBeijing 100083P.R.China Institute of Mathematics Academy of Mathematics and System SciencesChinese Academy of SciencesBeijing 100190P.R.China school of sciences Hangzhou Dianzi UniversityHangzhou 310012P.R.China school of Mathematical sciences and LPMC Nankai UniversityTianjin 300071P.R.China

We investigate the uniqueness problems of meromorphic functions and their difference operators by using a new *** is proved that if a non-constant meromorphic function f shares a non-zero constant and ∞ counting multiplicities with its difference operators Δcf(z) and Δ_(c)^(2)f(z), thenΔcf(z)≡Δ_(c)^(2)f(z).In particular,we give a difference analogue of a result of *** method has two distinct features:(ⅰ) It converts the relations between functions into the corresponding *** makes it possible to deal with the uniqueness problem by linear algebra and combinatorics.(ⅱ) It circumvents the obstacle of the difference logarithmic derivative lemma for meromorphic functions of infinite order,since this method does not depend on the growth of the ***,the idea in this paper can also be applied to the case for several variables.

关键词： Uniqueness meromorphic functions difference operators infinite order

Cyclic Pulsating Pressure Enhanced Segregating Structuration of Ultra-High Molecular Weight Polyethylene/Graphene Composites as High-performance Light-Weight EMI Shields

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Chinese Journal of Polymer science 2024年第7期42卷 958-967,I0008页

作者： Yun-Zhi Huang xiao-xiao Liu Lan-Wei Li Guang-Ming Huang Zhao-Xia Huang Jin-Ping Qu National Engineering Research Center of Novel Equipment for Polymer Processing Key Laboratory of Polymer Processing EngineeringMinistry of EducationGuangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced ManufacturingSchool of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou 510641China school of Advanced Manufacturing technology Guangdong Mechanical&Electrical PolytechnicGuangzhou 510550China

Currently,the enhancement in electromagnetic interference(EMI)performance of polymeric composite generally relies on either improving electrical conductivity(σ)for stronger electromagnetic(EM)reflections or tailoring structure for higher EM ***,we proposed a novel technique called cyclic pulsating pressure enhanced segregating structuration(CPP-SS),which can reinforce these two factors *** structural information was supplied by optical microscopy(OM)and scanning electron microscopy(SEM),both of which confirmed the formation and evolution of segregate structured ultra-high molecular weight polyethylene(UHMWPE)/graphene ***,the result showed that CPP-SS can significantly improve theσof ***,advanced specific EMI shielding efficiency of 3..1 d B/mm was achieved for UHMWPE/graphene composite at 1-mm thickness and a low graphene loading of 5 wt%.Meanwhile,it also confirmed that the intrinsic disadvantage of poor mechanical properties of conventional segregated structure composites can be *** work is believed to provide a fundamental understanding of the structural and performance evolutions of segregated structured composites prepared under CPPSS,and to bring us a simple and efficient approach for fabricating high-performance,strong and light-weight polymeric EMI shields.

关键词： Cyclic pulsating pressure Segregated structure Ultra-high molecular weight polyethylene Graphene Electromagnetic interface