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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

Mechanical property of cylindrical sandwich shell with gradient core of entangled wire mesh

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Defence Technology（防务技术） 2024年第1期31卷 510-522页

作者： Xin xue Chao Zheng Fu-qiang Lai xue-qian Wu Institute of Metal-rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou350116China Fujian Metallurgical Industry Design Institute Fuzhou350116China

To explore the wide-frequency damping and vibration-attenuation performances in the application of aerospace components,the cylindrical sandwich shell structure with a gradient core of entangled wire mesh was proposed in this ***,the gradient cores of entangled wire mesh in the axial and radial directions were prepared by using an in-house Numerical Control weaving machine,and the metallurgical connection between skin sheets and the gradient core was performed using vacuum ***,to investigate the mechanical properties of cylindrical sandwich shells with axial or radial gradient cores,quasi-static and dynamic mechanical experiments were carried *** primary evaluations of mechanical properties include secant stiffness,natural frequency,Specific Energy Absorption(SEA),vibration acceleration level,and so *** results suggest that the vibration-attenuation performance of the sandwich shell is remarkable when the high-density core layer is at the end of the shell or abuts the inner *** axial gradient material has almost no influence on the vibration frequencies of the shell,whereas the vibration frequencies increase dramatically when the high-density core layer approaches the ***,compared to the conventional sandwich shells,the proposed functional grading cylindrical sandwich shell exhibits more potential in mass reduction,stiffness designing,and energy dissipation.

关键词： Entangled wire mesh Gradient cylindrical sandwich shell Vacuum brazing Secant stiffness Damping

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数字化线上音频对大学生英语听力能力的影响

昌吉学院学报 2021年第1期 121-124页

作者：薛振红南通大学杏林学院江苏南通226000

此实证研究旨于探究数字化线上音频对大学生英语听力能力的影响。通过选择我校2018级大学英语学习者50名作为研究对象,开展数字化线上音频英语听力训练,拟解决数字化线上音频对大学生英语听力准确性和质量有何影响、对不同水平学生英语... 详细信息

此实证研究旨于探究数字化线上音频对大学生英语听力能力的影响。通过选择我校2018级大学英语学习者50名作为研究对象,开展数字化线上音频英语听力训练,拟解决数字化线上音频对大学生英语听力准确性和质量有何影响、对不同水平学生英语听力有何影响两个问题。研究结果显示不同水平学生听力训练质量均得到提升,错误率降低,其中低水平改善情况更为显著。在此基础上,该文章对我国网络环境下大学生听力实证研究现状作了总结分析,提出了目前此研究领域的主要问题和后续研究方向,为听力实证研究更趋科学化提供建议,以期更好地指导听力研究与教学。

关键词：数字化听力能力网络环境研究设计

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浅析研究性学习

邵阳学院学报（社会科学版） 2002年第1期1卷 147-149页

作者：薛振红南通师范学院外文系，江苏南通226007

研究性学习已被正式纳入新的《课程标准》。我们可以从自身生话和社会生活中或者直接从教材中选择课题。我们也从图书馆、网络等方面获得一些有力的参考资料。在研究性学习中，教师还能够对研究性学习作一定的指导，学生间也可以互相合... 详细信息

研究性学习已被正式纳入新的《课程标准》。我们可以从自身生话和社会生活中或者直接从教材中选择课题。我们也从图书馆、网络等方面获得一些有力的参考资料。在研究性学习中，教师还能够对研究性学习作一定的指导，学生间也可以互相合作，共同讨论。但我们也清楚地看到学校领导、学生本身、家庭、社会等多方面的错误观念也制约着研究性学习的发展。教师素质、研究设备等多方面硬、软件的限制也在制约着研究性学习的进展，而且当前的评价标准还有待提高。

关键词：研究性学习观念问题教师素质设备限制评价标准

Doubled Hecke Algebras and Related Quantum Schur Duality

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Algebra Colloquium 2024年第3期31卷 417-428页

作者： Chenliang xue An Zhang School of Mathematical Sciences East China Normal University Shanghai 200241China

introduce the doubled Hecke algebra,which is an infinite-dimensional algebra generated by two Hecke *** concept originates from the degenerate doubled Hecke algebra in the theory of Schur-Weyl duality related to enhanced reductive algebraic *** study the finite-dimensional natural representation of the doubled Hecke algebra on tensor space and prove that the doubled Hecke algebra forms a duality with the quantum group of Levi type.

关键词： quantum group doubled Hecke algebra quantum q-Schur duality double centralizer

Evolution of pore systems in low-maturity oil shales during thermal upgrading--Quantified by dynamic SEM and machine learning

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Petroleum Science 2024年第3期21卷 1739-1750页

作者： Jun Liu xue Bai Derek Elsworth Key Laboratory of Deep Underground Science and Engineering(Ministry of Education) Institute of New Energy and Low-Carbon TechnologySichuan UniversityChengdu610065SichuanChina International Quantum Academy Shenzhen518048GuangdongChina Shenzhen Institute of Advanced Electronic Materials Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen518055GuangdongChina Department of Energy and Mineral Engineering Pennsylvania State University ParkPA 16802USA

In-situ upgrading by heating is feasible for low-maturity shale oil,where the pore space dynamically *** characterize this response for a heated substrate concurrently imaged by *** systematically follow the evolution of pore quantity,size(length,width and cross-sectional area),orientation,shape(aspect ratio,roundness and solidity)and their anisotropy—interpreted by machine *** indicate that heating generates new pores in both organic matter and inorganic ***,the newly formed pores are smaller than the original pores and thus reduce average lengths and widths of the bedding-parallel pore ***,the average pore lengths and widths are increased in the bedding-perpendicular ***,heating increases the cross-sectional area of pores in low-maturity oil shales,where this growth tendency fluctuates at300℃.In addition,the orientation and shape of the newly-formed heating-induced pores follow the habit of the original pores and follow the initial probability distributions of pore orientation and ***,limited anisotropy is detected in pore direction and shape,indicating similar modes of evolution both bedding-parallel and *** propose a straightforward but robust model to describe evolution of pore system in low-maturity oil shales during heating.

关键词： Low-maturity oil shale Pore elongation Organic matter pyrolysis In-situthermal upgrading Scanning electron microscopy(SEM) Machine learning

Thermodynamic property of sandwich cylindrical shell structure with metallic wire mesh:Numerical modeling and experimental analysis

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Chinese Journal of Aeronautics 2024年第1期37卷 138-152页

作者： Xin xue Guojian SHEN Juan LIAO Institute of Metal Rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou 350116China Fujian Shuikou Power Generation Group Co. LTDFuzhou 350000China

As a new addition to lightweight composite structures,the sandwich cylindrical shell with a metallic wire mesh core has emerged as a promising solution for thermodynamic performance analysis at elevated *** intricate interwoven cellular formations within the metallic wire mesh pose difficulties for thermo-mechanical modeling and property ***,the constitutive models employed to characterize hysteresis phenomena were presented,comprising isotropic elasticity,Bergstrom-Boyce model,Ogden hyper-elasticity,and parameter identification through mechanical examinations at varying ***,the finite element modeling of cylindrical shell structures was determined for modal and steady-state dynamic ***,the experimental procedures were carried out,including the preparation of the sandwich cylindrical shell and the dynamic testing *** first-order natural frequency of the cylindrical shell structure is close to the resonance frequency of the dynamic test results,with a maximum error of 6.5%,demonstrating the accuracy of the simulation *** compared to the solid-core cylindrical shell,the average insertion loss of the sandwich cylindrical shell structure within the frequency range of 10–1000 Hz at room temperature is up to 11.09 ***,at elevated temperatures,the average insertion loss of the sandwich cylindrical shell decreases but fluctuates as the temperature changes.

关键词： Energy dissipation Metallic matrix composites Numerical analysis Sandwich structure Thermodynamic properties

Linear Quadratic Optimal Control for Systems Governed by First-Order Hyperbolic Partial Differential Equations

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Journal of Systems Science & Complexity 2024年第1期37卷 230-252页

作者： xue Xiaomin XU Juanjuan ZHANG Huanshui School of Control Science and Engineering Shandong UniversityJinan 250061China College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266000China

This paper focuses on linear-quadratic(LQ)optimal control for a class of systems governed by first-order hyperbolic partial differential equations(PDEs).Different from most of the previous works,an approach of discretization-then-continuousization is proposed in this paper to cope with the infinite-dimensional nature of PDE *** contributions of this paper consist of the following aspects:(1)The differential Riccati equations and the solvability condition of the LQ optimal control problems are obtained via the discretization-then-continuousization method.(2)A numerical calculation way of the differential Riccati equations and a practical design way of the optimal controller are ***,the relationship between the optimal costate and the optimal state is established by solving a set of forward and backward partial difference equations(FBPDEs).(3)The correctness of the method used in this paper is verified by a complementary continuous method and the comparative analysis with the existing operator results is *** is shown that the proposed results not only contain the classic results of the standard LQ control problem of systems governed by ordinary differential equations as a special case,but also support the existing operator results and give a more convenient form of computation.

关键词： Discretization-then-continuousization method first-order hyperbolic partial differential equations forward and backward partial difference equations linear quadratic optimal control.

Pathway Planning of Nuclear Power Development Incorporating Assessment of Nuclear Event Risk

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 500-513页

作者： Xinxin Yang Yusheng xue Bin Cai School of Electrical Engineering Southeast UniversityNanjingChinaand they are also with State Grid Electric Power Research Institute(NARI Group Corporation)NanjingChina State Key Laboratory of Smart Grid Protection and Operation Control NanjingChina State Grid Electric Power Research Institute(NARI Group Corporation) NanjingChina

The nuclear event risk(NER)is an important and disputed factor that should be reasonably considered when planning the pathway of nuclear power development(NPD)to assess the benefits and risks of developing nuclear power more *** paper aims to explore the impact of nuclear events on NPD pathway *** influence of nuclear events is quantified as a monetary risk component,and an optimization model that incorporates the NER in the objective function is *** optimize the pathway of NPD in the lowcarbon transition course of power supply structure evolution,a simulation model is built to deduce alternative NPD pathways and corresponding power supply evolution scenarios under the constraint of an exogenously assigned carbon emission pathway(CEP);moreover,a method is proposed to describe the CEP by superimposing the maximum carbon emission space and each carbon emission reduction(CER)component,and various CER components are clustered considering the emission reduction characteristics and resource endowments of different power generation technologies.A case study is conducted to explore the impact of NER and its risk valuation uncertainty on NPD pathway *** method presented in this paper allows the impact of nuclear events on NPD pathway planning to be quantified and improves the level of coordinated optimization of benefits and risks.

关键词： Low-carbon transition power supply structure evolution nuclear power development(NPD) quantitative analysis nuclear event risk evaluation