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Neural Dynamics for Distributed Collaborative Control of Manipulators With Time Delays

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IEEE/CAA Journal of Automatica Sinica 2022年第5期9卷 854-863页

作者： Long Jin xin zheng xin Luo School of Information Science and Engineering Lanzhou UniversityLanzhou 730000 IEEE State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China School of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqing 400065 Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China

Time-delay phenomena extensively exist in practical systems,e.g.,multi-agent systems,bringing negative impacts on their *** work analyzes a collaborative control problem of redundant manipulators with time delays and proposes a time-delayed and distributed neural dynamics *** assumptions that the network topology is fixed and connected and the existing maximal time delay is no more than a threshold value,it is proved that all manipulators in the distributed network are able to reach a desired *** proposed distributed scheme with time delays considered is converted into a time-variant optimization problem,and a neural dynamics solver is designed to solve it ***,the proposed neural dynamics solver is proved to be stable,convergent and ***,the allowable threshold value of time delay that ensures the proposed scheme’s stability is *** examples and comparisons are provided to intuitively prove the validity of the proposed neural dynamics scheme and solver.

关键词： Distributed collaborative control neural dynamics redundancy resolution repetitive motion planning(RMP) time delay

Super-resolution processing of passive millimeter-wave images based on adaptive projected Landweber algorithm

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Journal of Systems Engineering and Electronics 2008年第4期19卷 709-716页

作者： zheng xin Yang Jianyu School of Electronic and Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

Passive millimeter wave （PMMW） images inherently have the problem of poor resolution owing to limited aperture dimension. Thus, efficient post-processing is necessary to achieve resolution improvement. An adaptive projected Landweber （APL） super-resolution algorithm using a spectral correction procedure, which attempts to combine the strong points of all of the projected Landweber （PL） iteration and the adaptive relaxation parameter adjustment and the spectral correction method, is proposed. In the algorithm, the PL iterations are implemented as the main image restoration scheme and a spectral correction method is included in which the calculated spectrum within the passband is replaced by the known low frequency component. Then, the algorithm updates the relaxation parameter adaptively at each iteration. A qualitative evaluation of this algorithm is performed with simulated data as well as actual radiometer image captured by 91.5 GHz mechanically scanned radiometer. From experiments, it is found that the super-resolution algorithm obtains better results and enhances the resolution and has lower mean square error （MSE）. These constraints and adaptive character and spectral correction procedures speed up the convergence of the Landweber algorithm and reduce the ringing effects that are caused by regularizing the image restoration problem.

关键词： passive millimeter wave imaging super-resolution Landweber algorithm inverse problems spectral extrapolation.

Monocular camera and 3D lidar joint calibration

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The Journal of China Universities of Posts and Telecommunications 2020年第4期27卷 91-98页

作者： zheng xin Wu Xiaojun School of Software Engineering Xi'an Jiaotong UniversityXi'an 710049China

Joint calibration of sensors is an important prerequisite in intelligent driving scene retrieval and recognition. A simple and efficient solution is proposed for solving the problem of automatic joint calibration registration between the monocular camera and the 16-line lidar. The study is divided into two parts: single-sensor independent calibration and multi-sensor joint registration, in which the selected objective world is used. The system associates the lidar coordinates with the camera coordinates. The lidar and the camera are used to obtain the normal vectors of the calibration plate and the point cloud data representing the calibration plate by the appropriate algorithm. Iterated closest points(ICP) is the method used for the iterative refinement of the registration.

关键词： calibration registration monocular camera 16-line lidar multi-sensor ICP

Finite-time control of formation system for multiple flight vehicles subject to actuator saturation

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Journal of Systems Engineering and Electronics 2020年第5期31卷 1019-1030页

作者： ZHAO Enjiao ZHONG Zenan zheng xin School of Automation Harbin Engineering UniversityHarbin 150001China Shanghai Academy of Spaceflight Technology Shanghai 200233China

This paper investigates the problem of formation tracking control for multiple flight vehicle(MFV) system considering actuator saturation constraints. First, the formation tracking control model is established. Then, the problem of formation control of the MFV system is converted to the convergence of a dynamical system, which is obtained by using the differential geometry theory.A class of saturation functions is introduced, and on this basis a second-order finite-time formation control protocol is *** the help of the homogeneous theory and Lasalle's invariance principle, it is theoretically proved that the designed formation protocol could complete the formation task in finite time, and the control inputs are shown to remain within their available actuating limits. Finally, simulations are performed to verify the effectiveness of the scheme.

关键词： formation control multiple flight vehicle(MFV) finite-time actuator saturation

Dynamic phase transition theory

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Science China(Physics,Mechanics & Astronomy) 2023年第2期66卷 102-108页

作者： Qi-Jun Ye xin-zheng Li State Key Laboratory for Artificial Microstructure and Mesoscopic Physics Frontier Science Center for Nano-optoelectronics and School of PhysicsPeking UniversityBeijing 100871China Interdisciplinary Institute of Light-Element Quantum Materials Research Center for Light-Element Advanced Materialsand Collaborative Innovation Center of Quantum MatterPeking UniversityBeijing 100871China Peking University Yangtze Delta Institute of Optoelectronics Nantong 226010China

Thermodynamic conventions suffer from describing dynamical distinctions,especially when the structural and energetic changes induced by rare events are *** using the ensemble theory in the trajectory space,we present a statistical approach to address this *** than spatial particle-particle interaction which dominates thermodynamics,the temporal correlation of events dominates the *** zeros of dynamic partition function mark phase transitions in the space-time,i.e.,dynamic phase transition(DPT),as Yang and Lee formulate traditional phase transitions,and hence determine dynamic phases on both sides of the *** to the role of temperature(pressure) as thermal(mechanical) potential,we interpret the controlling variable of DPT,i.e., dynamic field,as the dynamical *** findings offer possibility towards a unified picture of phase and phase transition.

关键词： transition phase transition

Effect on the Emergence of Cultural School of the Diversity of British Novel in the Renaissance

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学术界 2015年第10期 276-281页

作者： zheng xin School of Music Jinan University Jinan Shandong 250100

The diversified development of British novels in the Renaissance mainly displays in several aspects,that is,lateral reflection of the social development background,specific expression of forming complex psychology of developing social mission,and macro manifestation of the basic needs of the *** is the important factor of contemporary cultural school to find the innovative development road,and also the crucial effect to explore and excavate the development characteristics of contemporary cultural school,expressing the time promoting effect of the development of the diversified development of British novels in the *** from the development characteristics of the C ultural School,the development direction between the social characteristics of times and the basic demand of social groups on social culture agrees with the diversified development of British novels in the Renaissance,and fully demonstrates the effect and value of the latter on the overall development of social cultural school.

关键词：文艺复兴时期社会文化小说英国学派多元化发展社会发展心理发展

Remark on Mild Solution to the 3D Incompressible Micropolar System in Fourier–Herz Framework

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Acta Mathematica Sinica,English Series 2019年第10期35卷 1595-1616页

作者： Yao NIE Xiao xin zheng School of Mathematics and Systems Science Beihang University

This paper is devoted to investigating the existence and uniqueness of mild solution to the 3D incompressible micropolar fluid system in the Fourier–Herz framework. By taking advantage of microlocal analysis and the mutual effect in the same frequency range of convection term, we give a special initial data(u0,ω0) whose norm of FB1,q^-1(q>2) is arbitrarily small, however, the couple(u0,ω0) produces a solution which is arbitrarily large in FB1,q^-1 after an arbitrarily short time. This implies the system is ill-posed in the sense of "norm inflation" as q>2.

关键词： Ill-posedness micropolar system Fourier-Herz space norm inflation

The humoral and cellular immune evasion of SARS-CoV-2 Omicron and sub-lineages

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Virologica Sinica 2022年第6期37卷 786-795页

作者： Tiandan Xiang Junzhong Wang xin zheng Department of Infectious Diseases Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Joint International Laboratory of Infection and Immunity Huazhong University of Science and TechnologyWuhan 430022China

The recently discovered SARS-CoV-2 variant Omicron(B.1.1.529) has rapidly become a global public health *** substantial mutations in the spike protein in this new variant have raised concerns about its ability to escape from pre-existing immunity established by natural infection or vaccination. In this review, we give a summary of current knowledge concerning the antibody evasion properties of Omicron and its subvariants(BA.2, BA.2.12.1,BA.4/5, and BA.2.75) from therapeutic monoclonal antibodies and the sera of SARS-CoV-2 vaccine recipients or convalescent patients. We also summarize whether vaccine-induced cellular immunity(memory B cell and T cell response) can recognize Omicron specifically. In brief, the Omicron variants demonstrated remarkable antibody evasion, with even more striking antibody escape seen in the Omicron BA.4 and BA.5 sub-lineages. Luckily, the third booster vaccine dose significantly increased the neutralizing antibodies titers, and the vaccine-induced cellular response remains conserved and provides second-line defense against the Omicron.

关键词： SARS-CoV-2 Omicron Vaccine Antibody evasion Cellular immunity

Experimental Study of the Removal of Fine Particulate Matter and Moisture from Flue Gas

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Journal of Thermal Science 2023年第6期32卷 2273-2283页

作者： zheng xin LU Yuan WANG Bo ZHAO Lifeng CAS Key Laboratory of Advanced Energy and Power Institute of Engineering ThermophysicsBeijing100190China University of Chinese Academy of Sciences Beijing100049China

Liquid desiccant systems are promising methods to recover water and waste heat simultaneously from flue *** research found that the reduction of particulate matter could occur during the absorption *** the present paper,experiments were carried out to explore the effect of removing fine particulate matter(PM_(2.5))in a liquid desiccant *** calcium chloride(CaCl_(2))was used as the desiccant in the *** discrepancies in mass and energy conservation were within±10%and±15%,respectively,which showed the good reliability of the experimental ***,23.5%–46.0%of the PM_(2.5)and 23.9%–45.1%of the moisture in the flue gas were *** comparing the desiccant solution and water,it was found that they could minimally remove PM_(2.5)through washing the flue *** of whether the flue gas was dehumidified by water or the solution,the removal fractions of PM_(2.5)of these two methods could be very close if they achieve the same fraction of moisture *** the results of a parameter analysis,it was found that the removal fraction of PM_(2.5)was nearly proportional to the removal fraction of moisture within the experimental range.

关键词： flue gas fine particulate matter removal dehumidification