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On the Pathwise Uniqueness of Solutions of One-dimensional Reflected Stochastic Differential Equations with Jumps

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 149-163页

作者： Hua zhang School of Statistics and Data Science&Key Laboratory of Data Science in Finance and Economics Jiangxi University of Finance and EconomicsNanchang330013China

In this paper, we are concerned with the problem of the pathwise uniqueness of one-dimensional reflected stochastic differential equations with jumps under the assumption of non-Lipschitz continuous coefficients whose... 详细信息

关键词： reflected diffusion processes with jumps pathwise uniqueness local time Meyer It?'s formula

Accumulated-state-error-based event-triggered sampling scheme and its application to H∞ control of sampled-data systems

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Science China(Information Sciences) 2024年第6期67卷 328-341页

作者： Xian-Ming zhang Qing-Long HAN Bao-Lin zhang Xiaohua GE Dawei zhang School of Science Computingand Engineering TechnologiesSwinburne University of Technology College of Automation and Electronic Engineering Qingdao University of Science & Technology School of Mathematics Shandong University

This paper is concerned with event-triggered H∞control of sampled-data systems. Its novelties lie in three aspects:（i） A novel accumulated-state-error-based event-triggered scheme is introduced by comparing the integral of the state error from tk to t with the system state sampled at tk. This condition works well due to the fact that the so-called Zeno behaviour does not occur.（ii） A novel Lyapunov functional is constructed to establish a criterion to ensure some certain H∞performance of the closed-loop system. This Lyapunov functional is dependent on the integral of the state error involved in the event-triggered scheme.（iii） Under the event-triggered sampling scheme, suitable state-feedback controllers can be designed rather than be given a priori. Moreover, a self-triggered implementation of the proposed event-triggered sampling scheme is presented as well. Finally, a batch reactor model and an inverted pendulum system are given to demonstrate the effectiveness of the proposed method.

关键词： event-triggered sampling self-triggered implementation $H_\infty$ control looped-functional

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基于脉冲变压器的快前沿固态触发器

强激光与粒子束 2024年第2期36卷 22-27页

作者：叶明天张迎鹏龙天骏王真中国工程物理研究院核物理与化学研究所四川绵阳621900

结合理论求解、仿真分析与实验验证,确定了影响脉冲变压器型触发器输出前沿的主要因素,并研制了一台能可靠触发真空沿面闪络开关导通的快前沿固态触发器。研究结果表明:影响触发器输出脉冲前沿的关键因素为脉冲变压器漏感、匝数比和半... 详细信息

结合理论求解、仿真分析与实验验证,确定了影响脉冲变压器型触发器输出前沿的主要因素,并研制了一台能可靠触发真空沿面闪络开关导通的快前沿固态触发器。研究结果表明:影响触发器输出脉冲前沿的关键因素为脉冲变压器漏感、匝数比和半导体开关开通速度;不同绕制方式的脉冲变压器漏感差异很大,最小漏感绕法的变压器漏感值低1个数量级;选用开通速度优于15 ns的碳化硅金属氧化物半导体场效应晶体管(SiC MOSFET)、绕制低漏感(小于0.5μH)的脉冲变压器,实现了前沿为20.4 ns(10%~90%)、幅值为16.5 kV的快前沿输出;控制SiC MOSFET的驱动脉宽在35~55 ns变化可以控制触发电流峰值在35~55 A范围内变化。

关键词：固态触发源脉冲变压器快前沿输出真空沿面闪络开关

Dynamics of a Reaction-diffusion-ODE System in a Heterogeneous Media

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 275-301页

作者： Cong-hui zhang Hai-feng zhang Mei-rong zhang School of Science Beijing University of Civil Engineering and ArchitectureBeijing 102616China Institute of Applied System Analysis Jiangsu UniversityZhenjiang 212013China Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

The existence and stability of stationary solutions for a reaction-diffusion-ODE system are investigated in this *** first show that there exist both continuous and discontinuous stationary *** a good understanding of the stability of discontinuous stationary solutions is gained under an appropriate *** addition,we demonstrate the influences of the diffusion coefficient on stationary *** results we obtained are based on the super-/sub-solution method and the generalized mountain pass ***,some numerical simulations are given to illustrate the theoretical results.

关键词： reaction-diffusion-ODE system discontinuous stationary solutions stability asymptotic behavior monotone solutions

“体医结合”方式下高校校园运动风险管理路径探寻

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当代体育科技 2021年第27期11卷 236-238页

作者：王亚萱章天军浙江海洋大学浙江舟山316004 浙江舟山群岛新区旅游与健康职业学院浙江舟山306004

为响应国家新课改的教学要求,各个高校都在不断发展体育运动,越来越多的学生参与到了运动之中,但运动也具有一定的风险,学生在了解运动的好处同时也要清晰地认识到运动风险的高发性。在校园中更要注意运动风险的管理,尽量避免学生在运... 详细信息

为响应国家新课改的教学要求,各个高校都在不断发展体育运动,越来越多的学生参与到了运动之中,但运动也具有一定的风险,学生在了解运动的好处同时也要清晰地认识到运动风险的高发性。在校园中更要注意运动风险的管理,尽量避免学生在运动过程中受伤,高校校园的运动管理者应学会在“体医结合”的方式下进行运动风险管理,进而确保学生的安全。

关键词：体医结合高校校园运动风险管理路径探寻

Structure characterization of the oxide film on FGH96 superalloy powders with various oxidation degrees

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International Journal of Minerals,Metallurgy and Materials 2024年第9期31卷 2037-2047页

作者： Yang Liu Yufeng Liu Sha zhang Lin zhang Peng zhang Shaorong zhang Na Liu Zhou Li Xuanhui Qu Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China Science and Technology on Advanced High Temperature Structural Materials Laboratory AECC Beijing Institute of Aeronautical MaterialsBeijing 100095China

The structure of the oxide film on FGH96 alloy powders significantly influences the mechanical properties of *** this study,FGH96 alloy powders with various oxygen contents were investigated using high-resolution transmission electron microscopy and atomic probe technology to elucidate the structure evolution of the oxide *** dispersive spectrometer analysis revealed the presence of two distinct components in the oxide film of the alloy powders:amorphous oxide layer covering the γ matrix and amorphous oxide particles above the *** alloying elements within the oxide layer showed a laminated distribution,with Ni,Co,Cr,and Al/Ti,which was attributed to the decreasing oxygen equilibrium pressure as oxygen diffused from the surface into the γ *** the other hand,Ti enrichment was observed in the oxide particles caused by the oxidation and decomposition of the carbide *** analysis of the oxide film with oxygen contents of 140,280,and 340 ppm showed similar element distributions,while the thickness of the oxide film varies approximately at 9,14,and 30 nm,*** findings provide valuable insights into the structural analysis of the oxide film on FGH96 alloy powders.

关键词： Ni-based superalloys surface structure oxide layer thickness oxidation behavior element distribution

A design and manufacturing methodology for encoded soft-textile robots

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 212-213页

作者： Yihui zhang Applied Mechanics Laboratory Department of Engineering MechanicsTsinghua UniversityBeijing 100084China

The development of programmable soft robots with bioinspired morphing capabilities has attracted considerable *** mode and complexity of morphing capabilities are essential to the manipulation and movement abilities o... 详细信息

关键词： environments robots manipulation

厚煤层采动覆岩裂隙分布特征及卸压瓦斯抽采技术

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煤矿安全 2020年第1期51卷 150-155页

作者：徐刚王云龙张天军潘红宇西安科技大学安全科学与工程学院陕西西安710054 西部矿井开采及灾害防治教育部重点实验室陕西西安710054 西安科技大学理学院陕西西安710054

针对崔家沟煤矿2303综放工作面瓦斯涌出量高易造成瓦斯超限的安全难题,应用采动裂隙椭抛带理论,在分析特厚煤层综放开采覆岩破坏特征的基础上,采用物理相似模拟和UDEC数值模拟试验研究了采空区覆岩"三带"演化规律,建立了采动裂隙椭抛带... 详细信息

针对崔家沟煤矿2303综放工作面瓦斯涌出量高易造成瓦斯超限的安全难题,应用采动裂隙椭抛带理论,在分析特厚煤层综放开采覆岩破坏特征的基础上,采用物理相似模拟和UDEC数值模拟试验研究了采空区覆岩"三带"演化规律,建立了采动裂隙椭抛带数学模型,确定出了覆岩裂隙瓦斯抽采有利区,提出了低-中-高位钻孔相组合的瓦斯抽采方案,并进行了工程应用。结果表明:2303综放工作面垮落带高度为33 m,断裂带高度为110 m,距离煤层底板35 m以上55 m以下与外椭抛面交集的范围为瓦斯抽采的有利区域;通过低-中-高位钻孔抽采方案的实施,上隅角瓦斯浓度小于0.6%,回风巷瓦斯浓度小于0.5%,有力保障了工作面的安全高效回采。

关键词：综放工作面采动覆岩裂隙 UDEC软件高位钻孔瓦斯抽采

Heterostructure Cu_(3)P-Ni_(2)P/CP catalyst assembled membrane electrode for high-efficiency electrocatalytic nitrate to ammonia

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Nano Research 2024年第6期17卷 4872-4881页

作者： Meng Jin Jiafang Liu Xian zhang Shengbo zhang Wenyi Li Dianding Sun Yunxia zhang Guozhong Wang Haimin zhang Laboratory of Materials Physics Centre for Environmental and Energy NanomaterialsAnhui Key Laboratory of Nanomaterials and NanotechnologyCAS Center for Excellence in NanoscienceInstitute of Solid State PhysicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Anhui Contango New Energy Technology Co. Ltd.Hefei 230031China

Electrochemical nitrate reduction reaction(NO_(3)RR)is a promising means for generating the energy carrier ***,we report the synthesis of heterostructure copper-nickel phosphide electrocatalysts via a simple vapor-phase hydrothermal *** resultant catalysts were evaluated for electrocatalytic nitrate reduction to ammonia(NH_(3))in three-type electrochemical *** detail,the regulation mechanism of the heterogeneous Cu_(3)P-Ni_(2)P/CP-x for NO_(3)RR performance was systematically studied through the H-type cell,rotating disk electrode setup,and membrane-electrode-assemblies(MEA)*** a result,the Cu_(3)P-Ni_(2)P/CP-0.5 displays the practicability in an MEA system with an anion exchange membrane,affording the largest ammonia yield rate(RNH_(3))of 1.9 mmol·h^(−1)·cm^(−2),exceeding most of the electrocatalytic nitrate reduction electrocatalysts reported to *** theoretical calculations and in-situ spectroscopy characterizations uncover that the formed heterointerface in Cu_(3)P-Ni_(2)P/CP is beneficial for promoting nitrate adsorption,activation,and conversion to ammonia through the successive hydrodeoxygenation pathway.

关键词： electrocatalytic nitrate reduction to ammonia three-type reactors membrane-electrode-assemblies system operando ATR-IRRAS successive hydrodeoxygenation pathway