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Factorization method for inverse obstacle scattering problem in three-dimensional planar acoustic waveguides

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Chinese Physics B 2018年第10期27卷 130-140页

作者： xue Qin School of Mathematical Sciences Peking UniversityBeijing 100871China

In this paper, we consider the inverse scattering problem of reconstructing a bounded obstacle in a three-dimensional planar waveguide from the scattered near-field data measured on a finite cylindrical surface containing the obstacle and corresponding to infinitely many incident point sources also placed on the measurement surface. The obstacle is allowed to be an impenetrable scatterer or a penetrable scatterer. We establish the validity of the factorization method with the nearfield data to characterize the obstacle in the planar waveguide by constructing an outgoing-to-incoming operator which is an integral operator defined on the measurement surface with the kernel given in terms of an infinite series.

关键词： factorization method planar waveguide inverse scattering problem

Character Sheaves for Classical Graded Lie Algebras

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Acta Mathematica Sinica,English Series 2024年第3期40卷 870-884页

作者： Ting xue School of Mathematics and Statistics University of MelbourneVIC 3010Australia Department of Mathematics and Statistics University of HelsinkiHelsinki 00014Finland

In this note we study character sheaves for graded Lie algebras arising from inner automorphisms of special linear groups and Vinberg’s type Ⅱ classical graded Lie algebras.

关键词： Graded Lie algebras character sheaves Fourier transform nilpotent orbits

Study of the material removal mechanism of glass-ceramics based on consecutive incremental loading in ductile-regime grinding

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Nanotechnology and Precision Engineering 2020年第2期3卷 88-95页

作者： xue Li State Key Laboratory of Precision Measuring Technology&Instruments Tianjin UniversityTianjin 300072China

Glass-ceramics have many excellent properties and are widely used in various fields. During the grinding process,the workpiece surface is typically subject to material removal by grit of incremental heights, which has rarely been the focus of research. As such, it is necessary to study the material removal mechanism of glass-ceramics under consecutive incremental loading, which more closely reflects the actual grinding process. In this paper,to analyze the plastic deformation and residual stress of lithium aluminosilicate(LAS) glass-ceramics, a finite element model is established based on the Drucker–Prager yield criterion for ductile regimes. A nano-scratch test was also conducted and the test results show that both the residual depth and residual stress increase with an increase in the number of increments, and that consecutive incremental loading promotes the plastic deformation of glass-ceramics and increases the residual stress of the material in the ductile-regime process. These findings provide guidance for achieving higher dimensional accuracy in the actual grinding of glass-ceramics parts.

关键词： Grinding Glass-ceramics Scratch tests Material removal mechanism Consecutive incremental loading

Current-carrying friction in carbon coated ball bearing

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Friction 2023年第11期11卷 2008-2020页

作者： Peidong xue Cheng CHEN xue FAN Dongfeng DIAO Institute of Nanosurface Science and Engineering(INSE) Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics EngineeringShenzhen UniversityShenzhen 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China

In this work,we proposed a method for coating the whole surfaces of bearing balls uniformly by carbon film with a rotatable ball *** studied the carbon/carbon friction with a self-designed currentcarrying ball bearing friction test system.A notable and instant friction force drop of 28%and significant carbon film wear alleviation were found when currents were *** using TEM-,SEM-,and EDS-analysis,special carbon stacks with a mixture of large wear particles and oxide were found in the wear areas under current applied *** elucidated the current-carrying friction mechanisms as follows:(1)wear particles formation;(2)wear particles charged by tribomicroplasma;(3)formation of surface passivated carbon stacks under electric force;(4)sliding between passivated carbon *** work may facilitate the development of novel solid-lubricated ball bearings and lay some foundations for current-carrying rolling friction.

关键词： current-carrying friction carbon film ball bearing carbon stack

Multiple optimal solutions to a sort of nonlinear optimization problem

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Journal of Systems Engineering and Electronics 2007年第1期18卷 63-67页

作者： xue Shengjia Management School Jinan Univ. Guangzhou 510632 P. R. China

The optimization problem is considered in which the objective function is pseudolinear（both pseudoconvex and pseudoconcave） and the constraints are linear. The general expression for the optimal solutions to the problem is derived with the representation theorem of polyhedral sets, and the uniqueness condition of the optimal solution and the computational procedures to determine all optimal solutions （if the uniqueness condition is not satisfied ） are provided. Finally, an illustrative example is also given.

关键词： Pseudolinear optimization problem Polyhedral set Representation theorem Multiple optimal solutions Convex simplex method

Approach for Obtaining Material Mechanical Properties in Local Region of Structure Based on Accurate Analysis of Micro-indentation Test

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Chinese Journal of Mechanical Engineering 2021年第6期34卷 147-158页

作者： He xue Jinxuan He Jianlong Zhang Yuxuan xue School of Mechanical Engineering Xi’an University of Science and TechnologyXi’an710054China Xi’an Special Equipment Inspection Institute Xi’an710065China Department of Industrial and Manufacturing Systems Engineering The University of Hong KongHong Kong999077China

The hot or cold processing would induce the change and the inhomogeneous of the material mechanical properties in the local processing region of the structure,and it is difficult to obtain the specific mechanical properties in these regions by using the traditional material tensile *** accurately get actual material mechanical properties in the local region of structure,a micro-indentation test system incorporated by an electronic universal material test device has been *** indenter displacement sensor and a group of special micro-indenter assemblies are estab-lished.A numerical indentation inversion analysis method by using ABAQUS software is also proposed in this *** on the above test system and analysis platform,an approach to obtaining material mechanical properties in the local region of structures is proposed and *** ball indentation test is performed and combined with the energy method by using various changed mechanical properties of 316L austenitic stainless steel under differ-ent *** investigated results indicate that the material mechanical properties and the micro-indentation morphological changes have evidently *** with the tensile test results,the deviations of material mechanical parameters,such as hardness H,the hardening exponent n,the yield strength σy and others are within 5%obtained through the indentation test and the finite element *** provides an effective and convenient method for obtaining the actual material mechanical properties in the local processing region of the structure.

关键词： Structural integrity assessment Micro-indentation test Numerical testing inversion analysis Local material mechanical property

A Controlled Phase Gate with Nitrogen-Vacancy Centers in Nanocrystal Coupled to a Silica Microsphere Cavity

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Chinese Physics Letters 2010年第6期27卷 5-8页

作者： xue Peng Department of Physics Southeast University Nanjing 211189

We show how a controlled phase gate, induced by adiabatic passage of dark states, can be implemented with the nitrogen-vacancy defects in nanocrystal coupled to the optical whispering gallery mode in a silica microsphere cavity. The gate presented is robust to the fluctuations of the experimental parameters compared to the dynamical and geometric phases gates. The feasibility of this scheme is characterized by exact numerical simulations that incorporate various sources of experiment noise. The results demonstrate the practicality by way of current experimental technologies.

关键词： Gates Experimentation

Overcoming drug efflux-based multidrug resistance in cancer with nanotechnology

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Chinese Journal of Cancer 2012年第2期31卷 100-109页

作者： xue, xue Liang, Xing-Jie Natl Ctr Nanosci & Technol China CAS Key Lab Biomed Effects Nanomat & Nanosafety Beijing 100190 Peoples R China

Multidrug resistance(MDR),which significantly decreases the efficacy of anticancer drugs and causes tumor recurrence,has been a major challenge in clinical cancer treatment with chemotherapeutic drugs for *** mechanisms of overcoming drug resistance have been *** known P-glycoprotein(P-gp) and other drug efflux transporters are considered to be critical in pumping anticancer drugs out of cells and causing chemotherapy *** theranostic(therapeutic and diagnostic) strategies with nanoparticles are rapidly evolving and are anticipated to offer opportunities to overcome these *** this review,we discuss the mechanisms of drug efflux-mediated resistance and the application of multiple nanoparticle-based platforms to overcome chemoresistance and improve therapeutic outcome.

关键词：抗癌药物多药耐药纳米技术外排癌症 P-糖蛋白临床治疗化疗药物

超前钻孔直径对高应力巷道卸压及掏槽爆破效果影响研究

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华北理工大学学报（自然科学版） 2025年第1期47卷 53-61页

作者：黄斌胡学龙安徽理工大学安徽省煤矿安全采掘装备制造业创新中心安徽淮南232001 中国矿业大学煤炭精细勘探与智能开发全国重点实验室江苏徐州221116 安徽理工大学矿业工程学院安徽淮南232001

随着煤炭开采逐步向深部推进,巷道开挖过程中应力集中问题日益突显,亟需有效解决。本文采用Ansys/Ls-Dyna数值模拟软件,针对高应力环境下不同超前钻孔直径对巷道卸压效果及掏槽爆破效果的影响进行了系统研究。利用ImageJ图像处理软件对... 详细信息

随着煤炭开采逐步向深部推进,巷道开挖过程中应力集中问题日益突显,亟需有效解决。本文采用Ansys/Ls-Dyna数值模拟软件,针对高应力环境下不同超前钻孔直径对巷道卸压效果及掏槽爆破效果的影响进行了系统研究。利用ImageJ图像处理软件对巷道掏槽爆破损伤云图进行了详细分析。结果表明,随着超前钻孔直径的增加,钻孔孔底至岩石内部区域的有效应力逐渐降低,有效实现了卸压作用;随着超前钻孔直径的增大,掏槽爆破岩石块度逐渐减少,小块度占比显著增加,且在大直径钻孔爆破中岩石块度的分布更为均匀。研究成果对提升高应力巷道掏槽爆破效果具有重要指导意义。

关键词：高应力超前钻孔掏槽爆破数值模拟

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