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Metabolites of Icariin in the Gastrointestine of Rats Following Oral Administration

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Chinese Chemical Letters 1998年第10期9卷 957-959页

作者： Qiu, F Gu, MZ Tan, QS Chen, yJ Kano, y.yao, XS Shenyang Pharmaceut Univ Shenyang 110015 Peoples R China Hokkaido Coll Pharm Otaru Hokkaido Japan

Further investigation of the metabolites of orally administered icariin in rats was made. Two minor metabolites, icariside I and icariside II, were identified in gastric content, and two metabolites, icariside II and ... 详细信息

关键词： icariin icariside I icariside II icaritin metabolite

Robust Control for Static Loading of Electro-hydraulic Load Simulator with Friction Compensation

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Chinese Journal of Aeronautics 2012年第6期25卷 954-962页

作者： yao Jianyong JIAO Zongxia yao Bin School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 China Science and Technology on Aircraft Control Laboratory Beihang University Beijing 100191 China School of Mechanical Engineering Purdue University West Lafayette IN 47907 USA

Load simulator is a key test equipment for aircraft actuation systems in hardware-in-the-loop-simulation. Static loading is an essential function of the load simulator and widely used in the static/dynamic stiffness test of aircraft actuation systems. The tracking performance of the static loading is studied in this paper. Firstly, the nonlinear mathematical models of the hydraulic load simulator are derived, and the feedback linearization method is employed to construct a feed-forward controller to improve the force tracking performance. Considering the effect of the friction, a LuGre model based friction compensation is synthesized, in which the unmeasurable state is estimated by a dual state observer via a controlled learning mechanism to guarantee that the estimation is bounded. The modeling errors are attenuated by a well-designed robust controller with a control accuracy measured by a design parameter. Employing the dual state observer is to capture the different effects of the unmeasured state and hence can improve the friction compensation accuracy. The tracking performance is summarized by a derived theorem. Experimental results are also obtained to verify the high performance nature of the proposed control strategy.

关键词： electro-hydraulic load simulator robust control friction compensation feedback linearization LuGre model nonlinear control state estimation

A systematic framework to understand central bank digital currency

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Science China(Information Sciences) 2018年第3期61卷 206-213页

作者： Qian yao Institute of Digital Money of the People’s Bank of China

The ongoing research and development of digital fiat currency(DFC) have triggered attention of policy makers, regulators and the industrial and academic communities. But there is not yet a clear idea and blueprint of what DFC looks like. This paper establishes a systematic framework to analyze the essence and connotation of DFC from four dimensions: currency value, technical aspects, means of implementation and application scenarios. It is argued that DFC is a credit-based currency in terms of value, a crypto-currency from a technical perspective, an algorithm-based currency in terms of implementation and a smart currency in application scenarios. Compared with existing private digital currencies and electronic currencies, DFC will be equipped with brand new and higher qualities. The goal of Chinese DFC is to contribute to more stable value, more secure data, more powerful regulation, stronger empowerment of individuals in payment activities and smarter application. Chinese DFC should have qualities that enable it to provide better service for the public, to offer effective tools for macroeconomic control and to lay a solid foundation for Reg Tech development.

关键词： digital fiat currency credit-based currency crypto-currency algorithm-based currency smart currency central bank digital currency

Sheaves on non-reduced curves in a projective surface

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Science China Mathematics 2023年第2期66卷 237-250页

作者： yao yuan Beijing National Center for Applied Mathematics Academy for Multidisciplinary StudiesCapital Normal UniversityBeijing 100048China

Sheaves on non-reduced curves can appear in moduli spaces of 1-dimensional semistable sheaves over a surface and moduli spaces of Higgs bundles as *** estimate the dimension of the stack M_(X)(nC,χ)of pure sheaves supported at the non-reduced curve nC(n≥2)with C an integral curve on *** prove that the Hilbert-Chow morphism h_(L,χ):M_(X)^(H)(L,χ)→|L|sending each semistable 1-dimensional sheaf to its support has all its fibers of the same dimension for X Fano or with the trivial canonical line bundle and|L|contains integral curves.

关键词： 1-dimensional pure sheaves on projective surfaces Hilbert-Chow morphism Hitchin fibration stack

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Ablation behavior of(ZrC/SiC)_(3)alternate coating prepared on sharp leading edge C/C composites by CVD

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Journal of Materials Science & Technology 2022年第20期115卷 129-139页

作者： B.Li H.J.Li X.y.yao X.F.Tian y.J.Jia G.H.Feng State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi׳an 710072China

A(ZrC/SiC)_(3)alternate coating was deposited on sharp leading edge(SLE)C/C composites by chemical vapor deposition(CVD).The ablation behavior was examined via oxyacetylene torch with heat flux of 2.38 MW/m^*** results indicated that the alternate coating exhibited great ablation resistance,providing an effective protection for C/C *** initial rapid heating stage,the(ZrC/SiC)_(3) alternate coating can relieve thermal stress,avoiding the peeling of coating and keeping an intact coating *** subsequent ablation,the Si C layers in central region were consumed rapidly,leaving layered *** stacked ZrO_(2) layers were reserved with the assistance of the release of thermal stress by interspaces,offering a great anti-scouring *** transition and border regions,the alternate Si C layers can delay oxygen erosion of inner coating and C/C substrate by the formation of SiO_(2).It is believed that the results would be helpful for the design and application of anti-ablation coatings on SLE C/C composites.

关键词： Alternate coating ZrC/SiC Sharp leading edge Chemical vapor deposition C/C composites

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异构无人系统协同控制研究进展

工程科学学报 2025年第1期47卷 66-78页

作者：郭兴李擎姚其家鲁小雅北京科技大学自动化学院北京100083 工业过程知识自动化教育部重点实验室北京100083

面对复杂化、多样化和立体化的任务需求,异构无人系统将空、地、海跨域优势互补,最大化提升系统各方面能力,为未来协同作战和智慧民生提供有力的技术保障.首先,梳理了国内外在跨域协同领域出台的推动性文件,介绍了异构无人系统在军用、... 详细信息

面对复杂化、多样化和立体化的任务需求,异构无人系统将空、地、海跨域优势互补,最大化提升系统各方面能力,为未来协同作战和智慧民生提供有力的技术保障.首先,梳理了国内外在跨域协同领域出台的推动性文件,介绍了异构无人系统在军用、科研院所和民用等三方面的实际应用.其次,针对异构无人系统关键技术之一的协同控制,分别阐述了异构无人系统协同控制在一致性、轨迹跟踪和编队‒合围等三方面的最新进展.此外,还特别讨论了在不同通信条件下协同控制所面临的挑战和解决方案.其中,由于一致性和轨迹跟踪存在上层控制理论性和下层控制可行性的区别,进一步从滑模控制、自适应控制、反步控制和自适应动态规划等四方面对轨迹跟踪研究展开阐述.然后,为了更好地促进异构无人系统协同控制在实际中的应用,通过总结前人相关工作,讨论了其在多约束控制与实时性、多任务切换控制和跨域通信下稳定性等三方面亟需解决的技术瓶颈.最后,综合异构无人系统协同控制研究现状和实际需求来看,指出了其在深度强化学习与分布式博弈、人机交互以及反群体智能等三方面的发展趋势.

关键词：异构无人系统协同控制跨域协同任务需求技术瓶颈

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WAVEFORM RELAXATION METHODS OF NONLINEAR INTEGRAL-DIFFERENTIAL-ALGEBRAIC EQUATIONS

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Journal of Computational Mathematics 2005年第1期23卷 49-66页

作者： yao-linJiang DepartmentofMathematicalSciences Xi'anJiaotongUniversityXi'an710049China

In this paper we consider continuous-time and discrete-time waveform relaxation meth-ods for general nonlinear integral-differential-algebraic equations. For the continuous-time case we derive the convergence condition of the iterative methods by invoking the spec-tral theory on the resulting iterative operators. By use of the implicit difference forms,namely the backward-differentiation formulae, we also yield the convergence condition of the discrete waveforms. Numerical experiments are provided to illustrate the theoretical work reported here.

关键词： nonlinear integral-differential-algebraic equations waveform relaxation parallel solutions convergence of iterative methods engineering applications

Loading-unloading judgement for advanced plastic UH model

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Acta Mechanica Sinica 2020年第4期36卷 827-839页

作者： X.Feng y.P.yao R.N.Li Z.Wan X.Dai College of Airport Civil Aviation University of ChinaTianjin 300300China School of Transportation Science and Engineering Beihang UniversityBeijing 100191China School of Automobile and Transportation Tianjin University of Technology and EducationTianjin 300222China Research Institute of Base and Foundation China Academy of Building ResearchBeijing 100013China

The unified hardening(UH)model proposed by.yao et al.(Geotechnique 2009)is the constitutive model which can consider the influence of the complex stress path and stress history on the deformation and strength of clays ***,the loading-unloading criterion of material model is defined as the change law of the intersection of current yield surface and the p axis,which makes the loading-unloading in the process of hardening and softening can be unified considered in UH ***,the Newton-Raphson method is adopted to attain the nonlinear problems solution in the finite element method of UH model,and the semi-implicit return mapping method is adopted to update *** application of the UH model in the finite element is *** then,the analyses of triaxial test are performed using the unit prediction and finite element *** results of the unit prediction method are compared with the experimental results to illustrate the rationality of the UH *** the results with the unit prediction method and the finite element method,the correctness of the finite element program of the UH model is ***,Ae three-dimensional firdte element andysis of embankment on soft soil is performed by the *** comparison between the results calculated by the UH model and the modified Cam-clay(MCC)model and the experimental data shows that the UH model is rational in analyzing the actual embankment engineering on soft soil.

关键词： Over-consolidated clay Unified hardening model Loading-unloading judgement Finite element method Stress-strain

Kerosene-fueled supersonic combustion modeling based on skeletal mechanisms

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Acta Mechanica Sinica 2019年第6期35卷 1155-1177页

作者： Wei yao Key Laboratory of High-Temperature Gas Dynamics Institute of MechanicsChinese Academy of ScienceBeijing 100190China School of Engineering Science University of Chinese Academy of ScienceBeijing 100049China

A brief review of the recent advances in kerosene-fueled supersonic combustion modeling is present by comparing the fuels,reviewing the kinetic mechanisms,and introducing recent modeling *** advantages and disadvantages of hydrogen and kerosene for the scramjet combustor are compared to show that kerosene is a more viable fuel option for a Mach number range of ***,detailed kinetic mechanisms for kerosene,which usually contain thousands of elementary reactions,must be significantly reduced for use in *** of this writing,the smallest skeletal kerosene mechanism has only 19 species and 53 reversible *** contrast to pioneer models based on global chemistry,the current kerosene-fueled supersonic combustion models based on reduced/skeletal chemistry are classified as *** influence of kinetic mechanisms,global equivalence ratios,inlet Mach number,geometric shape,and domain symmetry are reviewed based on high-fidelity models and available *** the advances in computational technology,models with accurate descriptions of both flow and chemistry are becoming a promising,indispensable approach for the study of supersonic combustion.

关键词： Kerosene Supersonic combustion Large eddy simulation Skeletal mechanism Scramjet