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Prescribed fast tracking control for flexible air-breathing hypersonic vehicles:An event-triggered case

Chinese Journal of Aeronautics 2021年第11期34卷 200-215页

作者： Xingling shao Yi shi Wendong ZHANG Jiang ZHAO The Key Laboratory of Instrumentation Science&Dynamic Measurement Ministry of EducationNorth University of ChinaTaiyuan 030051China School of Instrument and Electronics North University of ChinaTaiyuan 030051China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

In this paper,a prescribed fast tracking control scheme is proposed for Flexible Airbreathing Hypersonic Vehicles(FAHV)subject to lumped disturbances and limited *** maintain tracking errors of velocity and altitude converge to a predefined region with a prescribed time and release the transient intense fluctuations encountered in classical Prescribed Performance Control(PPC)using a fast decaying rate,a tracking differentiator-based PPC is presented,where the reaching time and the maximum time differentiation of preselected envelopes can be regulated as a prior via fixing an acceleration factor,so that a guaranteed fast convergence speed can be realized with reduced ***,to avoid the excessive occupation of limited resources(energy and communication)and guarantee a remarkable tracking accuracy,switching event-triggered mechanisms are constructed for FAHV control realization,which provide a promising way to pursue a desired level of tracking performance with a low energy ***,Uncertainty and Disturbance Estimators(UDE)and Sigmoid function-based Tracking Differentiators(STD)are employed to provide disturbance estimation and reference derivation with a low computational ***,robust control laws are designed to compensate for the sampling error induced by event-triggered conditions,meanwhile Zeno phenomena can be effectively *** simulation results and comparisons validate the effectiveness of the proposed scheme.

关键词： Flexible air-breathing hypersonic vehicle Prescribed performance control Switching event-triggered Tracking differentiator Uncertainty and disturbance estimator

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On a composition of subfactors with group subfactors

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Science China Mathematics 2021年第2期64卷 373-384页

作者： Xiaoyu Hu rui shi Feng Xu School of Mathematical Sciences Dalian University of TechnologyDalian 116024China Department of Mathematics Foshan UniversityFoshan 528225China Department of Mathematics University of California at RiversideRiversideCA 92521USA

Let M be a typeⅡ1 factor,G be a finite group,and N■M be an irreducible subfactor of finite *** prove that the composed lattice of the intermediate subfactor lattice for the inclusion N■M and the subgroup lattice of G can be realized as an intermediate subfactor lattice of a certain composed subfactor of finite index,and this subfactor also has finite depth when N■M has finite depth.

关键词： subfactor typeⅡ1 factor lattice

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Structural evolution and high-temperature sensing performance of polymer-derived SiAlBCN ceramics

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Journal of Advanced Ceramics 2024年第4期13卷 478-485页

作者： Chao Ma Kun Liu Pengfei shao Daoyang Han Kang Wang Mengmeng Yang rui Zhao Hailong Wang rui Zhang Gang shao School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Zhongyuan Critical Metal Laboratory Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentZhengzhou UniversityZhengzhou 450002China

In situ temperature monitoring has become extremely imperative in high-temperature harsh environments and polymer-derived ceramics(PDCs)as sensing materials have attracted great ***,the stability and oxidation/corrosion resistance of PDCs cannot be simultaneously achieved at the moment,limiting their practical ***,polymer-derived SiAlBCN ceramics were synthesized via polymer conversion method under different pyrolysis *** microstructure evolution,high temperature sensing properties,and stability were investigated in *** results show that the amorphous SiAlBCN phase grows more orderly and the size of the free carbon phase enlarges with the increasing *** defect concentration displays a decreasing ***,the SiAlBCN ceramics as sensing materials exhibit a good temperature-resistance property from roo temperature to 1100℃.The fabricated SiAlBCN temperature sensor possesses excellent stability,repeatability,and ***,SiAlBCN ceramics exhibit distinguished oxidation/corrosion resistance after 100 h treatment at 1200℃in a water/oxygen environment,which is attributed to their low corrosive rate constant(0.57 mg/(cm^(2)·h))and oxidative rate constant(3.43 mg^(2)/(cm^(4)·h)).Therefore,polymer-derived SiAlBCN ceramics as sensing materials,which possess outstanding stability and oxidation/corrosion resistance,have great potential for in-situ monitoring of extreme environmental temperatures in the future.

关键词： polymer-derived SiAlBCN ceramics temperature sensor harsh environments oxidation and corrosion resistance

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Optimization of equimolar reverse constant-temperature mass-diffusion process for minimum entransy dissipation

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Science China(Technological Sciences) 2016年第12期59卷 1867-1873页

作者： XIA shao Jun CHEN Lin Gen SUN Feng rui Institute of Thermal Science and Power Engineering Naval University of Engineering Military Key Laboratory for Naval ship Power Engineering Naval University of Engineering College of Power Engineering Naval University of Engineering

The mass entransy describes the mass-diffusion ability of the solution system, and the mass-diffusion process with the finite concentration difference always leads to the mass-entransy dissipation. This paper studies the equimolar reverse constant-temperature mass-diffusion process with Fick's law( g∝Δ(c)). The optimal concentration paths for the MED(Minimum Entransy Dissipation) are derived and compared with those for the MEG(Minimum Entropy Generation) and CCR(Constant Concentration Ratio) operations. It is indicated that the strategy of the MED is equivalent to that of the CCD(Constant Concentration Difference) of the same component; whether the MED or the MEG is selected as the optimization objective, the strategy of the CCD is much better than that of the CCR.

关键词： mass entransy finite time thermodynamics equimolar reverse mass-diffusion Fick's mass-diffusion law optimal concentration path generalized thermodynamic optimization

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Metal phosphides and borides as the catalytic host of sulfur cathode for lithium–sulfur batteries

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International Journal of Minerals,Metallurgy and Materials 2022年第5期29卷 990-1002页

作者： rui Gao Zhenyu Wang Sheng Liu Guangjie shao Xueping Gao College of Environmental and Chemical Engineering Yanshan UniversityQinhuangdao 066004China School of Materials Science and Engineering Nankai UniversityTianjin 300350China

Lithium−sulfur batteries are one of the most competitive high-energy batteries due to their high theoretical energy density of _(2)600 W·h·kg^(−1).However,their commercialization is limited by poor cycle stability mainly due to the low intrinsic electrical conductivity of sulfur and its discharged products(Li_(2)S_(2)/Li_(2)S),the sluggish reaction kinetics of sulfur cathode,and the“shuttle effect”of soluble intermediate lithi-um polysulfides in ether-based *** address these challenges,catalytic hosts have recently been introduced in sulfur cathodes to en-hance the conversion of soluble polysulfides to the final solid products and thus prevent the dissolution and loss of active-sulfur *** this review,we summarize the recent progress on the use of metal phosphides and borides of different dimensions as the catalytic host of sulfur cathodes and demonstrate the catalytic conversion mechanism of sulfur cathodes with the help of metal phosphides and borides for high-en-ergy and long-life lithium-sulfur ***,future outlooks are proposed on developing advanced catalytic host materials to improve battery performance.

关键词： lithium–sulfur batteries sulfur cathode catalytic host metal phosphides metal borides

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An M-VCUT level set-based data-driven model of microstructures and optimization of two-scale structures

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Frontiers of Mechanical Engineering 2024年第4期19卷 73-86页

作者： Minjie shao Tielin shi Qi XIA State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

The optimization of two-scale structures can adapt to the different needs of materials in various regions by reasonably arranging different microstructures at the macro scale,thereby considerably improving structural ***,a multiple variable cutting(M-VCUT)level set-based data-driven model of microstructures is presented,and a method based on this model is proposed for the optimal design of two-scale *** geometry of the microstructure is described using the M-VCUT level set method,and the effective mechanical properties of microstructures are computed by the homogenization ***,a database of microstructures containing their geometric and mechanical parameters is *** two sets of parameters are adopted as input and output datasets,and a mapping relationship between the two datasets is established to build the data-driven model of *** the optimization of two-scale structures,the data-driven model is used for macroscale finite element and sensitivity *** efficiency of the analysis and optimization of two-scale structures is improved because the computational costs of invoking such a data-driven model are much smaller than those of homogenization.

关键词： two-scale structure structural optimization M-VCUT level set homogenization radial basis function data-driven

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Porous hydrogel arrays for hepatoma cell spheroid formation and drug resistance investigation

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Bio-Design and Manufacturing 2021年第4期4卷 842-850页

作者： Xin Lei Changmin shao Xin Shou Keqing shi Liang shi Yuanjin Zhao Translational Medicine Laboratory The First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325035China Wenzhou Institute University of Chinese Academy of SciencesWenzhou 325001China State Key Laboratory of Bioelectronics School of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China Department of Laboratory Medicine The Eighth Affiliated HospitalSun Yat-Sen UniversityShenzhen 518033China

Drug resistance is one of the major obstacles in the drug therapy of *** in this area in pre-clinical research have focused on developing novel platforms to evaluate and decrease drug *** this paper,inspired by the structure of hives where swarms live and breed,we propose porous hydrogel arrays with a uniform pore structure for the generation of hepatoma cell spheroids and the investigation of drug *** porous hydrogel arrays were fabricated using polyeth-ylene glycol diacrylate(PEGDA)hydrogel to negatively replicate a well-designed *** from the elaborate processing of the template,the prepared porous hydrogel arrays possessed a uniform pore *** to their anti-adhesion properties and the excellent biocompatibility of the PEGDA hydrogel,the hepatoma cells could form well-defined and uni-form hepatoma cell spheroids in the porous hydrogel *** found that the resistant hepatoma cell spheroids showed more significant Lenvatinib resistance and a migratory phenotype compared with a two-dimensional(2D)cell culture,which reveals the reason for the failure of most 2D cell-selected drugs for in vivo *** features give such porous hydrogel arrays promising application prospects in the investigation of tumor cell spheroid culture and in vitro drug resistance.

关键词： Drug resistance Hydrogel Porous Spheroid Hepatoma

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Stereochemistry of Thionation Reaction of 1,3,2-Dioxaphosphorinan-2-ones with Lawessen's Reagent

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Chinese Chemical Letters 1997年第4期8卷 269-270页

作者： rui Lian shao Wei shi MIAO Guang Fu YANG(Institute of Elemento-Orgamc Chemistry, Nankai University, Tianin, 300071) Inst. of Elemento-Organic Chemistry Nankai University Tianjin 300071 China

The stereochemistry of thionation reaction of 2 -substituted 4 -aryl- 5, 5 dimethyl - 1. 3. 2 -dioxaphosphorian-ones 1a-r with Lautssen's reagent (LR ) was reported in this paPer. The results indicated that the thionation reaction of LR proceeded predominantly with retention of *** mechanism leading to retention was proposed by assuming a cyclic pentacoordinated intermidiate.

关键词： ppm

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Weakly Compact Sets and Riesz Representation Theorem in Musielak Sequence Spaces

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Acta Mathematica Sinica,English Series 2024年第2期40卷 467-484页

作者： Wan Zhong GONG Si Yu shi Zhong rui shi Department of Mathematics Anhui Normal UniversityWuhu 241000P.R.China Smeal College of Business Pennsylvania State UniversityUniversity ParkPennsylwania 16802USA Department of Mathematics Shanghai UniversityShanghai 200444P.R.China

In this work,we give some criteria of the weakly compact sets and a representation theorem of Riesz's type in Musielak sequence spaces using the ideas and techniques of sequence spaces and Musielak ***,as an immediate consequence of the criteria considered in this paper,the criteria of the weakly compact sets of Orlicz sequence spaces are deduced.

关键词： Compact set weak topology Banach space dual space Musielak sequence spaces

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Unfolding neutron spectra from water-pumping-injection multilayered concentric sphere neutron spectrometer using self-adaptive differential evolution algorithm

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Nuclear Science and Techniques 2021年第3期32卷 41-51页

作者： rui Li Jian-Bo Yang Xian-Guo Tuo Jie Xu rui shi Chengdu University of Technology Chengdu 610059China Sichuan University of Science and Engineering Zigong 643000China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province Chengdu 610059China

A self-adaptive differential evolution neutron spectrum unfolding algorithm(SDENUA)is established in this study to unfold the neutron spectra obtained from a water-pumping-injection multilayered concentric sphere neutron spectrometer(WMNS).Specifically,the neutron fluence bounds are estimated to accelerate the algorithm convergence,and the minimum error between the optimal solution and input neutron counts with relative uncertainties is limited to 10^(-6)to avoid unnecessary ***,the crossover probability and scaling factor are self-adaptively *** Monte Carlo is used to simulate the readings of the WMNS under(1)a spectrum of Cf-252 and(2)its spectrum after being moderated,(3)a spectrum used for boron neutron capture therapy,and(4)a reactor ***,the measured neutron counts are unfolded using the *** uncertainties of the measured neutron count and the response matrix are considered in the SDENUA,which does not require complex parameter tuning or an a priori default *** results indicate that the solutions of the SDENUA agree better with the IAEA spectra than those of MAXED and GRAVEL in UMG 3.1,and the errors of the final results calculated using the SDENUA are less than 12%.The established SDENUA can be used to unfold spectra from the WMNS.

关键词： Water-pumping-injection multilayered spectrometer Neutron spectrum unfolding Differential evolution algorithm Self-adaptive control

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