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A Weak∞-Functor in Morse Theory

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Acta Mathematica Sinica,English Series 2024年第11期40卷 2571-2614页

作者： shan zhong SUN Chen Xi WANG Department of Mathematics Capital Normal UniversityBeijing100048P.R.China Academy for Multidisciplinary Studies Capital Normal UniversityBeijing100048P.R.China

In the spirit of Morse homology initiated by Witten and Floer,we construct two∞-categories A and *** weak one A comes out of the Morse-Smale pairs and their higher homotopies,and the strict one B concerns the chain complexes of the Morse *** on the boundary structures of the compactified moduli space of gradient flow lines of Morse functions with parameters,we build up a weak∞-functor F:A→*** algebraic structures behind Morse homology are revealed with the perspective of defects in topological quantum field theory.

关键词： Morse function moduli space of gradient flow lines compactifications weak n/∞-category higher morphism homotopy

Efficient reinforcement learning in continuous state and action spaces with Dyna and policy approximation

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Frontiers of Computer Science 2019年第1期13卷 106-126页

作者： shan zhong Quan LIU Zongzhang ZHANG Qiming FU School of Computer Science and Technology Soochow UniversitySuzhou 215000China School of Computer Science and Engineering Changshu Institute of TechnologyChangshu 215500China Jiangsu Province Key Laboratory of Intelligent Building Energy Efficiency Suzhou University of Science and TechnologySuzhou 215006China Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education Jilin University Changchun 130012China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing 210000China College of Electronic &Information Engineering Suzhou University of Science and TechnologySuzhou 215000China

Dyna is an effective reinforcement learning (RL) approach that combines value function evaluation with model ***,existing works on Dyna mostly discuss only its efficiency in RL problems with discrete action *** paper proposes a novel Dyna variant,called Dyna-LSTD-PA,aiming to handle problems with continuous action ***-LSTD-PA stands for Dyna based on least-squares temporal difference (LSTD)and policy ***-LSTD-PA consists of two simultaneous,interacting *** learning process determines the probability distribution over action spaces using the Gaussian distribution;estimates the underlying value function,policy,and model by linear representation;and updates their parameter vectors online by LSTD(,t).The planning process updates the parameter vector of the value function again by using ofttine LSTD(2).Dyna-LSTD-PA also uses the Sherman-Morrison formula to improve the efficiency of LSTD(,t),and weights the parameter vector of the value function to bring the two processes ***,the global error bound is derived by considering approximation,estimation,and model ***,Dyna-LSTD-PA outperforms two representative methods in terms of convergence rate,success rate,and stability performance on four benchmark RL problems.

关键词： problem solving control methods heuristic search methods dynamic programming

Strategies for reopening in the forthcoming COVID-19 era in China

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National Science Review 2022年第3期9卷 5-6页

作者： Wei-jie Guan Nan-shan zhong State Key Laboratory of Respiratory Disease National Clinical Research Center for Respiratory Disease Guangzhou Institute of Respiratory Health The First Affiliated Hospital of Guangzhou Medical University Guangzhou Medical University Department of Thoracic Surgery Guangzhou Institute for Respiratory Health The First Affiliated Hospital of Guangzhou Medical University Guangzhou Medical University Department of Respiratory and Critical Care Medicine Foshan Second People's HospitalAffiliated Foshan Hospital of Southern Medical University

The transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the culprit pathogen of coronavirus disease 2019 (COVID-19), has resulted in more than 0.43 billion cases and 6 million deaths globally. Compared with other existing variants of concern, the Omicron variant is characterized by significantly greater infectivity (Ro≈6),greater tropism of the upper respiratory tract and lower severity of human infections [1].These characteristics of the Omicron variant are the basis upon which several developed countries are considering reopening.

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Immobilizing palladium nanoparticles on boron-oxygen-functionalized carbon nanospheres towards efficient hydrogen generation from formic acid

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Nano Research 2019年第12期12卷 2966-2970页

作者： shan zhong Nobuko Tsumori Mitsunori Kitta Qiang Xu Research Institute of Electrochemical Energy National Institute of Advanced Industrial Science and Technology(AIST)IkedaOsaka 563-8577Japan Graduate School of Engineering Kobe UniversityKobeHyogo 657-8501Japan Department of Applied Chemistry and Chemical Engineering Toyama National College of Technology13 Hongo-machiToyama 939-8630Japan AIST-Kyoto University Chemical Energy Materials Open Innovation Laboratory(ChEM-OIL) National Institute of Advanced Industrial Science and Technology(AIST)Kyoto 606-8501Japan

Carb on nanospheres(XC-72R)were functionalized by boron-oxygen(B-O)through coannealing with boric acid,to which highly dispersed palladium nanoparticles(Pd NPs)(-1.7 nm)were immobilized by a wet chemical reduction for the first *** resultant Pd/OB-C catalystexhibits significantly improved activity for the dehydrogenation from formic acid(FA)compared to pristine XC-72R supported Pd NPs(Pd/C).Impressively,by adding melamine precursor,the B-0 and nitrogen(N)-functionalized product OB-C-N displays an extremely high B content,ca.34 times higher than *** Pd/OB-C-N catalyst with an ultrafine Pd particle size of-1.4 nm shows a superb activity,with a turnoverfrequency(TOF)as high as 5,354 h^-1 at 323 K,owing to the uniform ultrafine Pd NPs and the effect from B-0 and N functionalities.

关键词： boron-oxygen function alization palladium formic acid heterogeneous catalysis hydrogen generation carbon nanosphere

Novel Method for the Enantioselective Synthesis of β-Lactams

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Chemical Research in Chinese Universities 2008年第1期24卷 58-64页

作者： YUAN Qing JIAN shan-zhong WANG Yan-guang Department of Chemistry Zhejiang University Hangzhou 310027 P. R. China

A novel method for the enantioselective synthesis of β-lactams is described in this study. 2,3-Dihydrobenzooxazin-4-one derived from salicylamide and L-menthone was used as the chiral auxiliary, which reacted with a-bromo-acyl bromides in the presence of pyridine to give carboximides 2. The stereo-controlled Reformatsky-type reactions of carboximides with imines yielded the corresponding trans β-lactams with high enantioselectivities（e.e. 75%-86%） and high chemical yields（63%-85%）, meanwhile, the chiral auxiliary dihydrobenzooxazin-4-one was released and recovered.

关键词： β-Lactams Enantioselective Chiralauxiliary Reformatskyreaction

Improved filtered-ε adaptive inverse control and its application on nonlinear ship maneuvering

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Journal of Systems Engineering and Electronics 2006年第4期17卷 788-792页

作者： Du Gang Zhan Xingqun Zhang Weiming zhong shan Inst. of Aerospace Science & Technology Shanghai Jiaotong Univ. Shanghai 200030 P. R. China The Second Academy of China Aerospace Science and Industry Corporation Beijing 100854 P. R. China

The drawbacks of common nonlinear Filtered-ε adaptive inverse control （AIC） method, such as the unreliability due to the change of delay time and the faultiness existing in its disturbance control loop, are discussed. Based on it, the diagram of AIC is amended to accommodate with the characteristic of nonlinear object with time delay. The corresponding Filtered-ε adaptive algorithm based on RTRL is presented to identify the parameters and design the controller. The simulation results on a nonlinear ship model of ＂The R.O.V Zeefakker＂ show that compared with the previous scheme and adaptive PID control, the improved method not only keeps the same dynamic response performance, but also owns higher robustness and disturbance rejection ability, and it is suitable for the control of nonlinear objects which have higher requirement to the maneuverability under complex disturbance environment.

关键词： adaptive inverse control nonlinear control RTRL ship maneuvering NARX network.

Study of nonlinear filter methods: particle filter

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Journal of Systems Engineering and Electronics 2006年第1期17卷 1-5页

作者： Zhang Weiming Du Gang zhong shan Zhang Yanhua Dept. of Information Measurement Technology and Instruments Shanghai Jiaotong Univ. Shanghai 200030 P.R. China The Second Academy China Aerospace Science and Industry Corporation Beijing 100854 P.R. China

Extended Kalman filter （EKF） is one of the most widely used methods for nonlinear system estimation. A new filtering algorithm, called particle filtering （PF） is introduced. PF can yield better performance than that of EKF, because PF does not involve the linearization approximating to nonlinear systems, that is required by the EKF. PF has been shown to be a superior alternative to the EKF in a variety of applications. The base idea of PF is the approximation of relevant probabifity distributions using the concepts of sequential importance sampling and approximation of probability distributions using a set of discrete random samples with associated weights. PF methods still need to be improved in the aspects of accuracy and calculating speed.

关键词： nonlinear extended Kalman filter particle filter Monte Carlo methods.

Photon sphere and phase transition of ddimensional(d≥5) charged Gauss–Bonnet AdS black holes

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Communications in Theoretical Physics 2020年第10期72卷 131-138页

作者： shan-zhong Han Jie Jiang Ming Zhang Wen-Biao Liu Department of Physics Beijing Normal UniversityBeijing 100875China College of Physics and Communication Electronics Jiangxi Normal UniversityNanchang 330022China Perimeter Institute for Theoretical Physics WaterlooOntario N2L 2Y5Canada Department of Physics and Astronomy University of WaterlooOntario N2L 3G1Canada

Motivated by recent work,nonmonotonic behaviors of photon sphere radius can be used to reflect black hole phase transition for Reissner–Nordstr?m–AdS(RN–AdS)black holes,we study the case of five-dimensional charged Gauss–Bonnet–AdS black holes in the reduced parameter *** find that the nonmonotonic behaviors of photon sphere radius still *** the coexistence line calculated from P–V plane,we capture the photon sphere radius of saturated small and large black holes(the boundary of the coexistence phase),then illustrate the reduced coexistence *** results show that,reduced coexistence region decreases with charge Q but increases with Gauss–Bonnet coefficientα.When the charge vanishes,reduced coexistence region does not vary with Gauss–Bonnet coefficientαany *** this case,the Gauss–Bonnet coefficientαplays the same role as the charge of five-dimensional RN–AdS black ***,the situation of higher dimension is studied in the end.

关键词： Gauss–Bonnet AdS black hole phase transition photon sphere black hole thermodynamics

Research on elevated temperature deformation behavior of Ti-6Al-4V sheets

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Rare Metals 2009年第6期28卷 550-553页

作者： SUN Shengdi GUO Bin shan Debin zhong Yingying School of Materials Science ＆ Engineering Harbin Institute of Technology Harbin 150001 China

Hot deformation behaviors were studied by means of scanning electron microscopy （SEM） and uniaxial thermal tension. The effect of deformation temperature and strain rate on flow stress was evaluated, and deformation mechanism was analyzed. The results show that the stress-strain curves of Ti-6Al-4V （TC4） alloy sheet and TC4 alloy bar at elevated temperatures have different forms and rules. Flow stress of TC4 is controlled by both strain rate and deformation temperature. The flow stress decreases with the increase of high temperature. Deformation mechanisms exhibit dynamic recovery and recrystallization feature within high temperature region and grain boundary slip behaviors at low temperature.

关键词： titanium alloys hot tension strain rate deformation temperature