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DEVELOPMENT AND MOTION ANALYSIS OF MINIATURE WHEEL-TRACK-LEGGED MOBILE ROBOT

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Chinese Journal of Mechanical Engineering 2007年第3期20卷 24-28页

作者： duan Xingguang HUANG Qiang XU Yan RAHMAN N zheng Change School of Mechatronics Engineering Beijing Institute of Technology Beijing 100081 China School of Vocational Technology Hebei Normal University Shijiazhuang 050031 China

A miniature wheel-track-legged mobile robot to carry out military and civilian missions in both indoor and outdoor environments is presented. Firstly, the mechanical design is discussed, which consists of four wheeled and four independently controlled tracked arms, embedded control system and teleoperation. Then the locomotion modes of the mobile robot and motion analysis are analyzed. The mobile robot can move using wheeled, tracked and legged modes, and it has the characteristics of posture-recovering, high mobility, small size and light weight. Finally, the effectiveness of the deve-loped mobile robot is confirmed by experiments such as posture recovering when tipped over, climb-ing stairs and traversing the high step.

关键词： Mobile robot Locomotion modes Stair-climbing Posture recovery

Agent-based Simulation Systems for Emergency Management

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International Journal of Automation and computing 2016年第2期13卷 89-98页

作者： Zhi-Chao Song Yuan-zheng Ge Hong duan Xiao-Gang Qiu College of Information System and Management National University of Defense Technology Hunan 410073 China Aeronautical University of China People Liberation Airforce Jilin 130012 China

Emergencies, which are very difficult to be forecasted, would always bring about huge harm to people. Therefore, to find ways to reduce such devastating effects, researches on emergency management have turned to be paramount. Nowadays, the rapid development of computer technology has supplied a new and effective idea for the researches of emergency management, namely that the researches can be done in computers by performing simulation experiments according to the artificial societies, computational experiments, parallel execution （ACP） approach. Guided by this approach, this paper has proposed one agent-based prototype simulation system to research emergency management. Firstly, structure of the simulation system oriented to emergency management was analyzed and designed. Then a simulation system oriented to public health emergency management was constructed to study the transmission of infectious diseases. Finally, several experiments were carried out based on the system, with several significant conclusions having also been obtained.

关键词： Agent-based simulation emergency management artificial societies computational experiments parallel execution (ACP) simulation system public health transmission of infectious diseases.

Synthesis of 3,3,5,5-tetrabenzyl-1,2,4-trithiol and 1,2-dis(1,3-arylpropan-2-yl)disulfane

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Chinese Chemical Letters 2013年第10期24卷 909-911页

作者： Fu Feng Meng Huang zheng-Chao duan Wei-Bing Hu School of Chemistry and Environmental Engineering Hubei Institute for Nationalities

Novel sulfur-containing compounds （3a-3c, 4a-4c） were obtained in ethanol with 1,3-diphenyl-2- propanone as the starting material. The advantages of this procedure were mild reaction conditions, simple protocol, and high yields. The structures of the products were characterized by IR, 1H NMR, MS and elementary analysis. The crystal of the new compound 4a belongs to monoclinic, space group C2 with a=18.727（3）, b=6.5179（9）, c=13.7576（18） A, fl=131.0610（10）°, V=I266.2（3）A3, Z=2, Dc=2.136g/cm3, μ=1.078mm 1, F（000）=843, R=0.0490 and wR=0.1247 for 3211 observed reflection with I 〉 2σ（I）. X-ray analysis reveals that the molecule is not symmetrical, the molecular structure is stabilized by weak π-π stacking interactions, and no classical hydrogen bonds can be observed.

关键词： 1 3-Diphenyl-2-propanone Synthesis Sulfur-containing compounds

Generative Adversarial Networks:Introduction and Outlook

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IEEE/CAA Journal of Automatica Sinica 2017年第4期4卷 588-598页

作者： Kunfeng Wang Chao Gou Yanjie duan Yilun Lin Xinhu zheng Fei-Yue Wang IEEE State Key Laboratory of Management and Control for Complex Systems Institute of Automation Chinese Academy of Sciences Qingdao Academy of Intelligent Industries State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of Sciences University of Chinese Academy of Sciences Department of Computer Science and Engineering University of Minnesota Research Center for Computational Experiments and Parallel Systems Technology National University of Defense Technology

Recently, generative adversarial networks(GANs)have become a research focus of artificial intelligence. Inspired by two-player zero-sum game, GANs comprise a generator and a discriminator, both trained under the adversarial learning *** goal of GANs is to estimate the potential distribution of real data samples and generate new samples from that *** their initiation, GANs have been widely studied due to their enormous prospect for applications, including image and vision computing, speech and language processing, etc. In this review paper, we summarize the state of the art of GANs and look into the future. Firstly, we survey GANs' proposal background,theoretic and implementation models, and application ***, we discuss GANs' advantages and disadvantages, and their development trends. In particular, we investigate the relation between GANs and parallel intelligence,with the conclusion that GANs have a great potential in parallel systems research in terms of virtual-real interaction and integration. Clearly, GANs can provide substantial algorithmic support for parallel intelligence.

关键词： ACP approach adversarial learning generative adversarial networks(GANs) generative models parallel intelligence zero-sum game

Stabilities and Dynamics of Protein Folding Nuclei by Molecular Dynamics Simulation

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Communications in Theoretical Physics 2017年第7期67卷 137-148页

作者： Yong-Shun Song Xin Zhou Wei-mou zheng Yan-Ting Wang School of Physical Sciences University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China

To understand how the stabilities of key nuclei fragments affect protein folding dynamics, we simulate by molecular dynamics （MD） simulation in aqueous solution four fragments cut out of a protein G, including one a-helix （seqB： KVFKQYAN）, two -turns （seqA： LNGKTLKG and seqC： YDDATKTF）, and one -strand （seqD： DGEWTYDD）. The Markov State Model clustering method combined with the coarse-grained conformation letters method are employed to analyze the data sampled from 2-#s equilibrium MD simulation trajectories. We find that seqA and seqB have more stable structures than their native structures which become metastable when cut out of the protein structure. As expected, seqD alone is flexible and does not have a stable structure. Throughout our simulations, the native structure of seqC is stable but cannot be reached if starting from a structure other than the native one, implying a funnel-shape free energy landscape of seqC in aqueous solution. All the above results suggest that different nuclei have different formation dynamics during protein folding, which may have a major contribution to the hierarchy of protein folding dynamics.

关键词： protein folding molecular dynamics simulation structure prediction

Cycloadditions of 1-iminylphosphirane complexes with allenes

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Chinese Chemical Letters 2021年第1期32卷 449-452页

作者： Juan Li Mingyue Cui Rongqiang Tian zheng duan François Mathey College of Chemistry Green Catalysis CenterInternational Phosphorus LaboratoryInternational Joint Research Laboratory for Functional Organophosphorus Materials of Henan ProvinceZhengzhou UniversityZhengzhou 450001China

A cascade carbonylative ring expansion and [2+2]/[4+2] cycloaddition of strained 1-iminylphosphirane complexes with aryl allenes were *** carbonylative ring expansion of 1-iminylphosphirane complexes provides an azaphosphacyclohexone complex intermediate with a C=P double *** following [2+2] or dearomatic [4+2] cycloaddition of this intermediate with allenes is modulated by the aryl substituents on the imino *** regioselective [2+2] cycloaddition with 1,1-diarylallene provides an entry to bicyclo[4.2.0]octan-4-one skeletons featuring a four-membered phosphacyclobutane *** dearomatic [4+2] cycloaddition was preferred with less aromatic naphthalene and yielded octahydrochrysene skeleton containing heteroatoms.

关键词： Phosphirane Allene Ring expansion Cycloaddition Carbonylative Heterocycle

Quantifying freeze-melt dynamics of lakes on the Tibetan Plateau using Sentinel-1 synthetic aperture radar imagery

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Journal of mountain Science 2024年第3期21卷 805-819页

作者： JIN Lu CHEN Jun CAI Yu KONG Yecheng WANG Yongfeng duan zheng School of Environment and Energy Engineering Anhui Jianzhu UniversityHefei 230601China Anhui Engineering and Technology Research Center for Smart City Anhui Jianzhu UniversityHefei 230601China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210023China Department of Physical Geography and Ecosystem Science Lund UniversityLund 22362Sweden

The ice phenology of alpine lakes on the Tibetan Plateau(TP)is a rapid and direct responder to climate changes,and the variations in lake ice exhibit high temporal frequency *** and passive microwave data are widely used to monitor lake ice changes with high temporal ***,the low spatial resolutions make it difficult to effectively quantify the freeze-melt dynamics of *** work used Sentinel-1 synthetic aperture radar(SAR)data to derive high-resolution ice maps(about 6 days),then with the aid of Sentinel-2 optical images to quantify freeze-melt processes in three typical lakes on the TP(*** Co,Ayakekumu Lake,and Nam Co).The results showed that three lakes had an average annual ice period of 125-157 days and a complete ice cover period of 72-115 days,from 2018 to *** exhibit different ice phenology *** Co is characterized by repeated episodes of freezing,melting,and refreezing,resulting in a prolonged freeze-up ***,the break-up period of Nam Co lasts for a longer duration(about 19 days),and the break-up exhibits a smooth ***,Ayakekumu Lake showed more significant inter-annual fluctuations in the freeze-up period,with deviations of up to 28 days observed among different *** to the other two lakes,Selin Co experienced a relatively short freeze-up and break-up *** short,Sentinel-1 SAR data can effectively monitor the weekly and seasonal variations in lake ice on the ***,this data facilitates quantification of the freeze-melt dynamics.

关键词： Lake ice Sentinel-1 SAR Tibetan Plateau Climate change

Selective C-C bonds formation,N-alkylation and benzo[d]imidazoles synthesis by a recyclable zinc composite

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Chinese Chemical Letters 2022年第1期33卷 266-270页

作者： Guanxin Zhu zheng-Chao duan Haiyan Zhu Dongdong Ye Dawei Wang The Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhou 510640China School of Chemical and Environmental Engineering Hubei Minzu UniversityEnshi 445000China

Earth abundant metals are much less expensive,promising,valuable metals and could be served as catalysts for the borrowing hydrogen reaction,dehydrogenation and heterocycles synthesis,instead of noble *** uniformly dispersed zinc composites were designed,synthesized and carefully characterized by means of XPS,EDS,TEM and *** resulting zinc composite showed good catalytic activity for the N-alkylation of amines with amines,ketones with alcohols in water under base-free conditions,while unsaturated carbonyl compounds could also be synthesized by tuning the reaction ***,it was the first time to realize the synthesis of 2-aryl-1H-benzo[d]imidazole derivatives by using this zinc composite under green ***,this zinc catalyst could be easily recovered and reused for at least five times.

关键词： Unsymmetrical Zinc Borrowing hydrogen Recyclability Selective

Learning from Spiropyrans:How to Make Further Developments of Donor-Acceptor Stenhouse Adducts

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Chinese Journal of Chemistry 2021年第4期39卷 985-998页

作者： Yongli duan Haiquan Zhao Chaoyue Xiong Lijun Mao Dongsheng Wang Yonghao zheng School of Optoelectronic Science and Engineering University of Electronic Science and Technology of ChinaJianshe North Road Section 2 No.4ChengduSichuan 610054China Institute of Electronic and Information Engineering of UESTC in Guangdong Zongbu Second Road No.17DongguanGuangdong523808 China

Donor-acceptor Stenhouse adducts(DASAs)as a species of novel photochromic molecules,have been developing rapidly and attracting broad researchers’sights since *** show visible/near-infrared(NIR)light induced linear-to-cyclic isomerization and heat induced cyclic-to-linear isomerization,therefore they are attractive in photoresponsive hydrogels,drug delivery,cell culturing and tissue *** a series of well-known photoresponsive molecules,spiropyrans(SPs)show similar molecular properties and comparable photoswitching with *** light triggers closed-to-open(also known as spirocyclic(SC)-to-merocyanine(MC))isomerization of SPs,while the reversed open-to-closed isomerization occurs under visible light or *** irradiation switches the molecular color,scale,geometry,and polarity of SPs and DASAs *** the researches on DASAs are still in the infancy,the chemical structures,isomerization mechanisms and potential applications need to be further investigated and *** well-studied SPs have important reference values to the comprehensive developments of *** the present review,we summarized,compared and discussed SPs and DASAs with regards to their molecular structures,synthesis,photoswitching and *** also make our perspective on the developments of DASA in future.

关键词： Photoresponsive Donor-acceptor Stenhouse adducts Spiropyrans Applications Isomerization