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A convergent mean shift algorithm to select targets for LAMOST

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Research in Astronomy and Astrophysics 2009年第7期9卷 803-811页

作者： guang-wei li Gang Zhao National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

This paper firstly finds that the Mean Shift Algorithm used by the Observation Control System （OCS） Research Group of the University of Science and Technology of China in Survey Strategy System 2.10 （SSS2.10） to select targets for the Large Sky Area Multi-Object Fiber Spectroscopic Telescope （LAMOST） is not convergent in theory. By carefully studying the mathematical formulation of the Mean Shift Algorithm, we find that it tries to find a point where some objective function achieves its maximum value; the Mean Shift Vector can be regarded as the ascension direction for the objective function. If we regard the objective function as the numerical description for the imaging quality of all targets covered by the focal panel, then the Mean Shift Algorithm can find the place where the imaging quality is the best. So, the problem of selecting targets is equal to the problem of finding the place where the imaging quality is the best. In addition, we also give some effective heuristics to improve computational speed and propose an effective method to assign point sources to the respective fibers. As a result, our program runs fast, and it costs only several seconds to generate an observation.

关键词： methods: data analysis - methods: statistical

Emerging approaches to probing ion channel structure and function

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Neuroscience Bulletin 2012年第4期28卷 351-374页

作者： wei-guang li Tian-Le Xu Neuroscience Division Department of Biochemistry and Molecular Cell BiologyInstitute of Medical SciencesShanghaiJiao Tong University School of MedicineShanghai 200025China

Ion channels,as membrane proteins,are the sensors of the *** act as the first line of communication with the world beyond the plasma membrane and transduce changes in the external and internal environments into unique electrical signals to shape the responses of excitable *** of their importance in cellular communication,ion channels have been intensively studied at the structural and functional ***,we summarize the diverse approaches,including molecular and cellular,chemical,optical,biophysical,and computational,used to probe the structural and functional rearrangements that occur during channel activation（or sensitization）,inactivation（or desensitization）,and various forms of *** emerging insights into the structure and function of ion channels by multidisciplinary approaches allow the development of new pharmacotherapies as well as new tools useful in controlling cellular activity.

关键词： ion channel structure and function mutagenesis covalent modification voltage-clamp fluorometry computational chemistry

Pyrolysis Characteristics and Kinetics of the Preparation Process of Sludge-Based Activated Carbon by ZnCl_2 Activation Method

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Journal of Harbin Institute of Technology(New Series) 2013年第6期20卷 29-36页

作者： Xin li guang-Zhi Wang wei-guang li Ping Wang School of Municipal and Environmental Engineering Harbin Institute of Technology State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology

To obtain the pyrolysis characteristics and kinetics of preparation process of sludge-based activated carbon by ZnCl2 activation method （*** pyrolysis process of the sludge with ZnCl2 activation）,the characteristic of mass loss and gas products generated during pyrolysis of the sludge with ZnCl2 activation were analyzed by thermogravimetric analysis coupled with Fourier Transform Infrared Spectroscopy （TG-FTIR）.The kinetic parameters were calculated by the Coats-Redfem method and the mechanism models were *** role of ZnCl2 in the pyrolysis process of the sludge with ZnCl2 activation was also illustrated through the comparison of the pyrolysis characteristics and kinetics of the sludge with and without ZnCl2 *** results showed that the pyrolysis process of the sludge with ZnCl2 activation can be divided into four stages including the dehydration of sludge and initial depolymerization of a small portion of organics matters,the decomposition of large molecular organic matters into small molecular intermediates,the further degradation of intermediates and volatilization of ZnCl2,and the decomposition of inorganic minerals and undecomposed organic ***2,CO,CH4,H2O,some aldehydes and carboxylic acids are the major pyrolysis gaseous *** activation energies and pre-exponential factors are in the range of 28.84-206.42 kJ/mol and 9885.16-8.08× 1011 min-1,*** the pyrolysis of sludge,ZnC12 not only can function as a dehydration agent and inhibit the formation of tar,but also can peptize the organic matters in the sludge,making them easier to be decomposed.

关键词： sludge ZnCl2 activation pyrolysisCLC number:X705 Document code:AArticle ID:1005-9113(2013)06-0029-08

Radar target recognition based on micro-Doppler effect

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Optoelectronics Letters 2008年第6期4卷 456-459页

作者： DONG wei-guang li Yan-jun College of Astronautics Northwestern Polytechnical University Xi ＇an 710072 China

Mechanical vibration of target structures will modulate the phase function of radar backscattering,and will induce the frequency modulation of returned signals from the target. It generates a side bands of the target body Doppler frequency shift,which is helpful for target recognition. Based on this,a micro-Doppler atomic storehouse is built for the target recognition,and four kinds of common classifiers are used separately to perform the classified recognition. The simulation experimental results show that this method has high recognition rate above 90%.

关键词：雷达目标显微多普勒效应信息处理后向散射

Molecular and functional characterization of three odorant-binding proteins from the wheat blossom midge,Sitodiplosis mosellana

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Insect Science 2020年第4期27卷 721-734页

作者： wei-Ning Cheng Yu-Dong Zhang wei liu guang-wei li Keyan Zhu-Salzman Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau Ministry of AgricultureNorthwest A&F UniversityYang lingShaanxiChina Shaanxi Key Laboratory of Chinese Jujube Van'an UniversityVan'anShaanxiChina Department of Entomology Texas A&M UniversityCollege StationTXUSA

Sitodiplosis mosellana,a periodic but devastating wheat pest,relies on wheat spike volatiles as a cue in sclecing hosts for *** odorant-binding proteins(OBPs)are thought to play essential roles in filtering,binding and transporting hydropho-bic odorant molecules to specific *** date,the molecular mechanisms underlying *** olfaction are poorly ***,three *** antenna-specific OBP genes,SmosOBPII,16 and 21,were cloned and bacterially *** properties of the recombinant proteins to 28 volatiles emitted from wheat spikes were in-vestigated using fluorescence competitive binding *** analysis suggested that these SmosOBPs belong to the Classic OBP ***-binding analysis showed that all three SmosOBPs preferentially bound alcohol,ester and ketone com-pounds,and SmosOBP11 and 16 also selectively bound terpenoid *** par-ticular,the three SmosOBPs had high binding affinities(Kilicited strong electroantennogram(EAG)response fromfemale *** addition,SmosOBP11 displayed significantly higher binding(Kilicited significant EAG response,suggesting that SmosOBP11 plays a ma-jor role in recognition and transportation of these *** findings have provided important insight into the molecular mechanism by which *** specifically rec-ognizes plant volatiles for host selection,and have facilitated identification of effective volatile attractants that are potentially useful for pest monitoring and trapping.

关键词： binding assay electroantennogram response host selection odorant-binding protein Sitodiplosis mosellana wheat spike violates

Segregating memories: targeting microenvironment of neuronal ensembles

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Signal Transduction and Targeted Therapy 2022年第11期7卷 3995-3997页

作者： Ying liu Miao Xu wei-guang li Department of Rehabilitation Medicine Huashan HospitalInstitute for Translational Brain ResearchState Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain ScienceFudan University200032ShanghaiChina

A recent study by Shen et *** that a delayed augmentation in the neuronal expression of C–C chemokine receptor type 5(CCR5)—a well-known immune molecule in the peripheral inflammatory microenvironment—after the acquisition of a contextual memory determines the duration of the temporal window for linking with another memory,effectively elucidating mechanisms that shape the memory linking timescales.

关键词： linking ensemble dating

Effects of PAHs on Biotransformation Enzymatic Activities in Fish

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Chemical Research in Chinese Universities 2011年第3期27卷 413-416页

作者： LU guang-hua CHEN wei li Ying ZHU Zhi Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes Ministry of Education College of Environment Hohai University Nanjing 210098 P. R. China

Biotransformation and detoxification responses to the exposure to five polycyclic aromatic hydrocarbons were investigated in crucian（Carassius auratus）. Juvenile crucian were treated with a single intraperitoneal injection of each compound at dosages of 0.1, 1.0, 2.0, 5.0 and 8.0（or 10.0） mg/kg and sacrificed 15 d later to determine 7-ethoxyresorufin-O-deethylase（EROD） and glutathione S-transferases（GST） activities in gill S9 fractions. EROD activity is significantly increased by benzo（b）fluoranthene and indeno（1,2,3-cd）pyrene at all the doses. High dosages of PAHs induced GST activity and the inducing ability of them increased in the following order： fluorene fluorantheneindeno（1,2,3-cd）pyrenebenzo（g,h,i）perylenebenzo（b）fluoranthene. In all the cases, dose dependence appeared to exist. The gill EROD and GST in Carassius auratus are useful biomarkers to estimate sub-acute toxicity of both polycyclic aromatic hydrocarbons（PAHs） and PAHs-like compounds.

关键词： Polycyclic aromatic hydrocarbon Gill 7-Ethoxyresorufin-O-deethylase activity Glutathione S-transferases activity

Predict the evolution of mechanical property of Al-li alloys in a marine environment

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Defence Technology（防务技术） 2024年第1期31卷 557-566页

作者： wei li lin Xiang guang Wu Hongli Si Jinyan Chen Yiming Jin Yan Su Jianquan Tao Chunyang Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100036China Chongqing Innovation Center Beijing Institute of TechnologyChongqing400044China First Research Institute of the Ministry of Public Security for PR China Beijing100036China Southwest Technology and Engineering Research Institute Chongqing400039China

The ocean is one of the essential fields of national defense in the future,and more and more attention is paid to the lightweight research of Marine equipment and *** study it is to develop a Machine learning(ML)-based prediction method to study the evolution of the mechanical properties of Al-li alloys in the marine *** obtained the mechanical properties of Al-li alloy samples under uniaxial tensile deformation at different exposure times through Marine exposure *** obtained the strain evolution by digital image correlation(DIC).The strain field images are voxelized using 2D-Convolutional Neural Networks(CNN)autoencoders as input data for Long Short-Term Memory(LSTM)neural ***,the output data of LSTM neural networks combined with corrosion features were input into the Back Propagation(BP)neural network to predict the mechanical properties of Al-li *** main conclusions are as follows:*** variation law of mechanical properties of2297-T8 in the Marine atmosphere is *** the increase in outdoor exposure test time,the tensile elastic model of 2297-T8 changes slowly,within 10%,and the tensile yield stress changes significantly,with a maximum attenuation of 23.6%.*** prediction model can predict the strain evolution and mechanical response simultaneously with an error of less than 5%.*** study shows that a CNN/LSTM system based on machine learning can be built to capture the corrosion characteristics of Marine exposure *** results show that the relationship between corrosion characteristics and mechanical response can be predicted without considering the microstructure evolution of metal materials.

关键词： Marine environment Al-li alloy Machine learning Corrosion

GPU-based cross-platform Monte Carlo proton dose calculation engine in the framework of Taichi

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Nuclear Science and Techniques 2023年第5期34卷 152-162页

作者： wei-guang li Cheng Chang Yao Qin Zi-Lu Wang Kai-Wen li li-Sheng Geng Hao Wu School of Physics Beihang UniversityBeijing 102206China Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of Radiation OncologyPeking University Cancer Hospital and Institute52 Fucheng RoadBeijing 100142China Medical Management Department CAS Ion Medical Technology Co.Ltd.Beijing 100190China Beijing Key Laboratory of Advanced Nuclear Materials and Physics Beihang UniversityBeijing 102206China School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China Institute of Medical Technology Peking University Health Science Center38 Xueyuan RoadBeijing 100191China

In recent years,graphics processing units(GPUs)have been applied to accelerate Monte Carlo(MC)simulations for proton dose calculation in ***,current GPU platforms,such as Compute Unified Device Architecture(CUDA)and Open Computing Language(OpenCL),suffer from cross-platform limitation or relatively high programming ***,the Taichi toolkit,which was developed to overcome these difficulties,has been successfully applied to high-performance numerical *** on the class II condensed history simulation scheme with various proton-nucleus interactions,we developed a GPU-accelerated MC engine for proton transport using the Taichi *** distributions in homogeneous and heterogeneous geometries were calculated for 110,160,and 200 MeV protons and were compared with those obtained by full MC simulations using *** gamma passing rates were greater than 0.99 and 0.95 with criteria of 2 mm,2%and 1 mm,1%,respectively,in all the benchmark ***,the calculation speed was at least 5800 times faster than that of TOPAS,and the number of lines of code was approximately 10 times less than those of CUDA or *** study provides a highly accurate,efficient,and easy-to-use proton dose calculation engine for fast prototyping,beamlet calculation,and education purposes.

关键词： Proton therapy Monte Carlo dose calculation GPU acceleration Taichi