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Bi-Lyapunov St able Homoclinic Classes for C^(1)Generic Flows

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Acta Mathematica Sinica,English Series 2021年第7期37卷 1023-1040页

作者： Ru song zheng School of Innovation and Entrepreneur ship Southern University of Science and TechnologyShenzhen 518055P.R.China

We study bi-Lyapunov stable homoclinic classes for a C^(1)generic flow on a closed Rieman-nian manifold and prove that such a homoclinic class contains no *** enables a parallel study of bi-Lyapunov stable dynamics for flows and for *** example,we can then show tha t a bi-Lyapunov st able homoclinic class for a C^(1)generic flow is hyperbolic if and only if all periodic orbits in the class have the same stable index.

关键词： Bi-Lyapunov stable homoclinic class singularity dominated splitting linear cocycle

ESO-based robust predictive control of lunar module with fuel sloshing dynamics

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Journal of Central South University 2017年第3期24卷 589-598页

作者： song zheng-yu College of Electrical Engineering Zhejiang UniversityHangzhou 310058China Beijing Aerospace Automatic Control Institute(BAACI) Beijing 100854China School of Aeronautics and Astronautics Central South UniversityChangsha 410083China

An extended-state-observer(ESO) based predictive control scheme is proposed for the autopilot of lunar *** slosh fuel masses exert forces and torques on the rigid body of lunar module(LM),such disturbances will dramatically undermine the stability of autopilot *** fuel sloshing dynamics and uncertainties due to the time-varying parameters are considered as a generalized disturbance which is estimated by an ESO from the measured attitude signals and the control input *** a continuous-time predictive controller driven by the estimated states and disturbances is designed to obtain the virtual control input,which is allocated to the real control actuators according to a deadband *** 6-DOF simulation results reveal the effectiveness of the proposed method when dealing with the fuel sloshing dynamics and parameter perturbations.

关键词： extended state observer predictive controller parameter perturbation fuel sloshing lunar module

Experimental Study of Kinetic Properties of Pyrolysis for Conveyor Belt in Coal Mine

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Journal of China University of Mining and Technology 2005年第4期15卷 314-316页

作者： song zheng-chang School of Mechanical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

The combustion of conveyor belt is a leading factor of mine fire. In this paper, the pyrolysis properties of ordinary conveyor belt and fire-resistant belt were studied experimentally with thermo-gravimetric analysis and derivative thermo-gravimetric analysis, and the curves of pyrolysis properties were achieved. On this basis, the activation energy and reaction order of pyrolysis were obtained in combination with theoretical analysis, aiming to provide data for further numerical simulation and simulating experiment of mine fire.

关键词： conveyor belt combustion pyrolysis mine fire

Emerging topics and new perspectives on regulatory and effector T cells

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Journal of Molecular Cell Biology 2012年第1期4卷 1-2页

作者： song Guo zheng Division of Rheumatology and Immunology Department of MedicineUniversity of Southern CaliforniaKeck School of MedicineLos AngelesCA 90033USA East Immunology Institute Tongji UniversityShanghai 200120Chin

It is well accepted that the balance of immunity between effector and regulatory T cells determines the outcome of autoimmune and chronic inflammatory *** the topic of‘Regulatory and Effector T Cells’as published in... 详细信息

关键词： immunity autoimmune cells

Optimization of CO_2 separation technologies for Chinese refineries based on a fuzzy comprehensive evaluation model

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Petroleum Science 2015年第1期12卷 197-206页

作者： Qian-Qian song Qing-Zhe Jiang Zhao-zheng song State Key Laboratory of Heavy Oil Processing China University of Petroleum

This study aims at determining the optimal CO2 separation technology for Chinese refineries, based on current available technologies, by the method of comprehensive evaluation. Firstly, according to the characteristics of flue gas from Chinese refineries, three feasible CO2 separation technologies are selected. These are pressure swing adsorption （PSA）, chemical absorption （CA）, and membrane absorption （MA）. Secondly, an economic assessment of these three techniques is carried out in accordance with cash flow analysis. The results show that these three techniques all have economic feasibility and the PSA technique is the best. Finally, to further optimize the three techniques, a two-level fuzzy comprehensive evaluation model is established, including economic, technological, and environmental factors. Considering all the factors, PSA is optimal for Chinese refineries, followed by CA and MA. Therefore, to reduce Chinese refineries carbon emission, it is suggested that CO2 should be captured from off-gases using PSA.

关键词： Chinese refineries CO2 emission Separation technique Economic evaluation AHP-entropy method Fuzzy comprehensive evaluation model

Absolute stabilization of singular systems with ferromagnetic hysteresis nonlinearity

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Science China(Information Sciences) 2013年第7期56卷 259-272页

作者： ZHANG HuaGuang WANG YingChun song zheng School of Information Science and Engineering Northeastern University Stake Key Laboratory of Synthetical Automation of Process Industies (Northeasten University) Beijing Institute of Spacecraft System Engineering

This paper is concerned with the absolute stabilization problem of a class of singular systems with feedback connected ferromagnetic hysteresis nonlinearities. Firstly, a novel differential-integral loop transformation framework is developed to achieve an augmented singular system model. Secondly, by constructing a new passive output derivative operator of hysteresis nonlinearity and establishing the bound condition of the solution of ferromagnetic hysteresis model, the equivalent absolute stability criterion of singular systems with hysteresis feedback is derived based on KYP method and LMIs technique. Furthermore, the strict LMIs conditions for absolute stabilization are obtained, which can easily be checked by the LMI toolbox in MATLAB. Finally, two examples are given to illustrate the effectiveness of the proposed method.

关键词： ferromagnetic hysteresis singular systems absolute stability extended Popov criterion

Particle Image Velocimetry Measurement of the Flow Field in the Play of the Drilling Pump Valve

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Chinese Journal of Mechanical Engineering 2010年第1期23卷 27-37页

作者： YANG Guoan YIN Xin song zheng HUANG Cong Diagnosis ＆ Self-recovery Engineering Research Center Beo＇ing University of Chemical Technology Beijing 100029 China Production Operations Center PetroChina Guangxi Petrochemical Company Qinzhou 535008 China

The failure of a drilling pump is always due to the break of the drilling pump valve, which is one of the most important but also the weakest parts of the drilling pump. Over the decades, the degradation of drilling pump valves has been investigated extensively and various failure mechanisms have been proposed. However, no experimental test on the fluid has been successfully performed to support some of these mechanisms. In this paper, tests of the flow within the valve play are carried out to investigate the factors resulting in the failure of the valve. In the tests, particle image velocimetry（PIV） technology is employed to measure the flow field distribution of the valve play in the model. From these tests, the distributions of velocity and vorticity of fluid in ＇various valves with different valve angles and different valve lifts are obtained, from which the features of flow fields are derived and generalized. Subsequently, a general rule of the influence of valve angles and valve lifts on the flow velocity is concluded according to chart analyses of maximal velocities and mean velocities. Finally, an analysis is made on the possibility of valve failure caused by erosion and abrasion in a working valve, with the application of the failure mechanisms of drilling pump valves. PIV measurement improves the study on the failure of the drilling pump valve, and the results show good agreement with previous computational fluid dynamics（CFD） simulations.

关键词： drilling pump valve flow field particle image velocimetry(PIV) valve failure

Antigen-non-specific regulation centered on CD25^(+)Foxp3^(+) Treg cells

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Cellular & Molecular Immunology 2010年第6期7卷 414-418页

作者： Gangzheng Hu Zhongmin Liu Changqing zheng song Guo zheng Key Laboratory of Stem Cell Biology Institute of Health SciencesShanghai Institutes for Biological SciencesChinese Academy of Sciences/Shanghai Jiao Tong University School of MedicineShanghaiChina Department of Gastroenterology Shengjing HospitalChina Medical UniversityShenyangChina Immune Tolerance and Regulation Center Shanghai East Hospital at Tongji UniveristyShanghaiChina Division of Rheumatology/Immunology Department of MedicineKeck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA

CD25^(+)Foxp3^(+) regulatory T cells(Tregs)are of special interest in immunology because of their potent inhibitory *** fundamental aspects of Tregs,including their antigenic profile,development and peripheral homeostasis,remain highly ***,we propose a Treg-centered antigen-non-specific immunoregulation model focused on the T-cell system,particularly on CD41 T *** T-cell pool consists of naive T cells(Tnais),Tregs and effector T cells(Teffs).Regardless of antigen specificity,the ratio of the activated T-cell subsets(Treg/Teff/Tnai)and their temporal and spatial uniformity dictate the differentiation of *** Tregs inhibit the activation,proliferation,induction and activity of Teffs;in contrast,activated Teffs inhibit the induction of Tregs from Tnais but cooperate with Treg-specific antigens to promote the proliferation and activity of *** many cases,these interactions are antigen-non-specific,whereas the activation of both Tregs and Teffs is *** T-cell subsets are essential for the maintenance of adaptive immune responses,but the antigen-non-specific interactions among T-cell subsets may be more important during the establishment of the adaptive immune system to a newly encountered *** is especially important when new and memory antigens are presented closely—both temporally and spatially—to T cells,because there are always baseline levels of activated Tregs,which are usually higher than levels of memory T cells for new *** on this hypothesis,we further infer that,under physiological conditions,Tregs in lymph nodes mainly recognize antigens frequently released from draining tissues,and that these self-reactive Tregs are commonly involved in the establishment of adaptive immunity to new antigens and in the feedback control of excessive responses to pathogens.

关键词： antigen immune regulation tolerance Treg

Rhodium(III)-Catalyzed Atroposelective C-H Indolylization of 1-Aryl Isoquinolines with 3-Indolylphenyliodonium Salts

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Chinese Journal of Chemistry 2023年第20期41卷 2684-2690页

作者： Dong-song zheng Jun zheng Qiang Wang Qing Gu Shu-Li You Chang-Kung Chuang Institute East China Normal University3663 N.Zhongshan RoadShanghai200062 China New Cornerstone Science Laboratory State Key Laboratory of Organometallic ChemistryShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling LuShanghai200032 China

Rhodium(III)-catalyzed enantioselective C-H indolylization of isoquinolines was *** C-H coupling reactions between 1-aryl isoquinoline derivatives and 3-indolylphenyliodonium salts proceeded smoothly in the presence of a modified chiral cyclopentadienyl-Rh(III)complex,affording a series of axially chiral indolylated biaryl products in excellent yields and enantioselectivity(up to 98%yield and 95%ee).

关键词： Asymmetric catalysis Axially chiral biaryl compounds C-H indolization Cross-coupling Enantioselectivity Rh catalysis