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Science Bulletin 2017年第15期62卷 1035-1038页

作者： Shuguang song Liming Yang Yuqi Zhang Yaoling Niu chao Wang Li Su Yanlin Gao MOE Key Laboratory of Orogenic Belt and Crustal Evolution School of Earth and Space Sciences Peking University Beijing 100871China Department of Earth Sciences Durham University Durham DHI 3LE UK Institute of Oceanology Chinese Academy of Science Qingdao 266071 China School of Scientific Research and State Key Laboratory of Geological Processes and Mineral Resources Chinese University of Geosciences Beijing 100083 China qinghai Science & Technology Department Xining 810000 China

Most orogenic belts have experienced a complex accretionary process with multiple episodes of sea?oor subduction and trench *** accretionary process is important in continenta development and growth[1,2].Three giant orogens extend in China,e.g.,the Central Asian Orogen in the north,the Central China Orogen in the middle and the Himalayan Orogen in the *** are keys for the formation of the Eurasian continent(Fig.1a).The Central China Orogen

关键词：中央造山带增生带早古生代堵塞沟槽弧形高原海洋

Research on the Bit Synchronization Algorithm and Multiplexing Technology in GNSS Receiver

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China Communications 2014年第A02期11卷 30-36页

作者： qi Jianzhong song Peng School of Computer and Communication Engineering University of Science and Technology Beijing Beijing 100083 ER. China North China University of Technology Beijing 100041 P. R. China

In this paper, the bit synchronization algorithms in GNSS receiver are introduced, including the traditional histogram method, K-P algorithm and Viterbi algorithm. The FPGA implementation is also included. A novel time division multiplexing technology （TDM） based on multi-channel shared synchronizer is proposed in this paper to solve the constrained hardware resource problem of multi-system satellite navigation receiver. Through the using of control state machine and data register structure, we realize the multiplexing of bit synchronizer of navigation receiver, which saves the hardware resource. After the experiment, it can be verified that the receiver based on the bit synchronization and multiplexing technology can correctly restore the navigation information.

关键词： bit synchronization carrier-to-noiseratio multiplexing GNSS

Positive eigenvalue-eigenvector of nonlinear positive mappings

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Frontiers of Mathematics in China 2014年第1期9卷 181-199页

作者： Yisheng song Liqun qi Department of Applied Mathematics The Hong Kong Polytechnic University Hong Kong China College of Mathematics and Information Science Henan Normal University Xinxiang 453007 China

We show that an （eventually） strongly increasing and positively homogeneous mapping T defined on a Banach space can be turned into an Edelstein contraction with respect to Hilbert＇s projective metric. By applying the Edelstein contraction theorem, a nonlinear version of the famous Krein- Rutman theorem is presented, and a simple iteration process {T^kx/｜｜T^kx｜｜} （ x ∈ P^＋） is given for finding a positive eigenvector with positive eigenvalue of T. In particular, the eigenvalue problem of a nonnegative tensor A can be viewed as the fixed point problem of the Edelstein contraction with respect to Hilbert＇s projective metric. As a result, the nonlinear Perron-Frobenius property of a nonnegative tensor A is reached easily.

关键词： Nonnegative tensor Edelstein contraction strongly increasing homogeneous mapping eigenvalue-eigenvector

Wavefield solutions from machine learned functions constrained by the Helmholtz equation

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Artificial Intelligence in Geosciences 2021年第1期2卷 11-19页

作者： Tariq Alkhalifah chao song Umair bin Waheed qi Hao Physical Sciences and Engineering Division King Abdullah University of Science and TechnologyThuwal23955Saudi Arabia Department of Geosciences King Fahd University of Petroleum and MineralsDhahran31261Saudi Arabia Center for Integrated Petroleum Research King Fahd University of Petroleum and MineralsDhahran31261Saudi Arabia

Solving the wave equation is one of the most(if not the most)fundamental problems we face as we try to illuminate the Earth using recorded seismic *** Helmholtz equation provides wavefield solutions that are dimensionally reduced,per frequency,compared to the time domain,which is useful for many applications,like full waveform ***,our ability to attain such wavefield solutions depends often on the size of the model and the complexity of the wave ***,we use here a recently introduced framework based on neural networks to predict functional solutions through setting the underlying physical equation as a loss function to optimize the neural network(NN)*** an input given by a location in the model space,the network learns to predict the wavefield value at that location,and its partial derivatives using a concept referred to as automatic differentiation,to fit,in our case,a form of the Helmholtz *** specifically seek the solution of the scattered wavefield considering a simple homogeneous background model that allows for analytical solutions of the background *** the NN with a reasonable number of random points from the model space will ultimately train a fully connected deep NN to predict the scattered wavefield *** size of the network depends mainly on the complexity of the desired wavefield,with such complexity increasing with increasing frequency and increasing model ***,smaller networks can provide smoother wavefields that might be useful for inversion *** tests on a two-box-shaped scatterer model with a source in the middle,as well as,the Marmousi model with a source at the surface demonstrate the potential of the NN for this *** tests on a 3D model demonstrate the potential versatility of the approach.

关键词： Helmholtz equation Wavefields Modeling Neural networks Deep learning

应用FFIITTC系统建立非均衡竞争游离甲状腺素化学发光法

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武警医学院学报 2012年第3期21卷 153-157页

作者：刘萍孔海霞张影田云霞宋启超涂值光重庆医科大学检验医学院重庆400016 博奥赛斯(天津)生物科技有限公司天津300162

【目的】制备抗人甲状腺素多克隆抗体并应用异硫氰酸荧光素（fluorescein isothiocyanate,FITC）系统建立非均衡竞争FT4化学发光法。【方法】以T4-牛血清白蛋白（bovin serum albumin,BSA）为抗原免疫新西兰兔,制备抗人T4多克隆抗体,亲... 详细信息

【目的】制备抗人甲状腺素多克隆抗体并应用异硫氰酸荧光素（fluorescein isothiocyanate,FITC）系统建立非均衡竞争FT4化学发光法。【方法】以T4-牛血清白蛋白（bovin serum albumin,BSA）为抗原免疫新西兰兔,制备抗人T4多克隆抗体,亲和层析法吸附掉与3-碘-L-甲状腺原氨酸（3-iodo-L-tyrosine）、3,5-二碘-L-甲状腺原氨酸（3,5-diiodo-L-tyrosine）、D-三碘甲状腺原氨酸（D-T3）、L-三碘甲状腺原氨酸（L-T3）、反三碘甲状腺原氨酸（rT3）有交叉反应多抗,纯化特异性的抗人T4多克隆抗体并用FITC标记T4类似物,用抗FITC抗体包被微孔板。反应时,将FT4校准品或样品、FITC-T4类似物、T4抗体-HRP依次加入包被有抗FITC抗体的化学发光板中,FITC-T4类似物与FT4校准品或样品,非均衡竞争结合T4抗体-HRP,从而在微孔板上形成免疫反应复合物T4类似物-T4抗体-HRP,通过酶促化学发光反应,就可以显示出与样品FT4浓度负相关的相对光单位（relative light unit,RLU）,建立FT4化学发光检测方法。【结果】抗体经酶联免疫吸附实验证明对T4具有高度特异性,与3-iodo-L-tyrosine、3,5-diiodo-L-tyrosine、L-T3、D-T3、rT3无交叉反应。该方法建立的试剂盒标准曲线的线性相关系数不小于0.9900;分析灵敏度为0.9 pmol/L;线性检测范围0.9~130 pmol/L;精密度测试批内变异系数CV〈10%;与进口发光免疫分析系统做线性相关比较,线性回归系数为1.0852,相关系数为0.9673,临床符合率良好;本方法建立的试剂盒经加速稳定性试验37℃放置7 d与2~8℃放置7 d无异。【结论】综上所述,应用FITC系统建立的非均衡竞争FT4化学发光免疫分析灵敏度高、特异性好适于临床诊断应用。

关键词：异硫氰酸荧光素非均衡竞争游离甲状腺素多克隆抗体化学发光法

Recent Advances on Neural Headline Generation

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Journal of Computer Science & Technology 2017年第4期32卷 768-784页

作者： Ayana Shi-qi Shen Yan-Kai Lin Cun-chao Tu Yu Zhao Zhi-Yuan Liu Mao-song Sun Department of Computer Science and Technology Tsinghua University Beijing 100084 China State Key Laboratory of Intelligent Technology and Systems Tsinqhua University Beijinq 100084 China Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing 100083 China Department of Computer Information Management Inner Mongolia University of Finance and Economics Hohhot 010000 China Jiangsu Collaborative Innovation Center for Language Ability Jiangsu Normal University Xuzhou 221009 China

Recently, neural models have been proposed for headline generation by learning to map documents to headlines with recurrent neural network. In this work, we give a detailed introduction and comparison of existing work and recent improvements in neural headline generation, with particular attention on how encoders, decoders and neural model training strategies alter the overall performance of the headline generation system. Furthermore, we perform quantitative analysis of most existing neural headline generation systems and summarize several key factors that impact the performance of headline generation systems. Meanwhile, we carry on detailed error analysis to typical neural headline generation systems in order to gain more comprehension. Our results and conclusions are hoped to benefit future research studies.

关键词： neural network headline generation data analysis

Atomically dispersed calcium as solid strong base catalyst with high activity and stability

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Green Energy & Environment 2024年第10期9卷 1619-1626页

作者： Xiang-Bin Shao Zhi-Wei Xing Si-Yu Liu Ke-Xin Miao Shi-chao qi song-song Peng Xiao-qin Liu Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech University30 South Puzhu RoadNanjing211816China

Solid strong base catalysts are highly attractive for diverse reactions owing to their advantages of neglectable corrosion,facile separation,and environmental ***,their widespread applications are impeded by basic components aggregation and low *** this work,we fabricate single calcium atoms on graphene(denoted as Ca1/G)by use of a redox strategy for the first time,producing solid strong base catalyst with high activity and *** precursor Ca(NO_(3))_(2)is first reduced to CaO at 400℃ by the support graphene,forming CaO/G with conventional basic sites,and the subsequent reduction at 850℃results in the generation of Ca1/G with atomically dispersed *** characterizations reveal that Ca single atoms are anchored on graphene in tetra-coordination(Ca-C_(2)-N_(2))where N is in situ doped from Ca(NO_(3))_(2).The atomically dispersed Ca,along with their anchoring on the support,endow Ca1/G with high activity and stability toward the transesterification reaction of ethylene carbonate with *** turnover frequency value reaches 128.0 h^(-1)on Ca1/G,which is much higher than the traditional counterpart CaO/G and various reported solid strong bases(2.9-46.2 h^(-1)).Moreover,the activity of Ca1/G is well maintained during 5 cycles,while 60%of activity is lost for the conventional analogue CaO/G due to the leaching of Ca.

关键词： Solid strong base Single Ca atoms Heterogeneous catalysts Transesterification Reaction

Seismic performance of a rectangular subway station with earth retaining system

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Earthquake Engineering and Engineering Vibration 2022年第1期21卷 221-236页

作者： Ma chao Lu Dechun Du Xiuli qi Chengzhi Beijing Advanced Innovation Center for Future Urban Design Beijing University of Civil Engineering andArchitectureBeijingChina Institute of Geotechnical and Underground Engineering Beijing University of TechnologyBeijingChina

Much effort has been made in investigating the seismic response and failure mechanism of rectangular subway stations,however,the influence of earth retaining systems has generally been ignored in previous *** paper presents a numerical study on the seismic performance of a rectangular subway station with/without earth retaining systems by taking fender piles as the example,and aims to illustrate how the existence of fender piles affects seismic responses on subway *** loading conditions of subway stations and their surrounding soils prior to earthquakes are ***,seismic responses of subway stations with or without fender piles were ***,earthquake-induced deformations of stations and surrounding soils,as well as the internal forces and damage modes of the structural components,were systematically ***,the seismic performance of the stations was affected by the existence of fender *** addition,earthquake intensity is *** study showed that deformation modes of surrounding soils and damage modes of stations were different with regard to the existence of fender ***,earthquake intensity influencing the seismic performance of stations with or without fender piles were found to be opposite.

关键词： rectangular subway station earth retaining system seismic soil-structure interaction damage mode inter-story drift ratio

Dynamic Scene Graph Generation of Point Clouds with Structural Representation Learning

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Tsinghua Science and Technology 2024年第1期29卷 232-243页

作者： chao qi Jianqin Yin Zhicheng Zhang Jin Tang School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing 100876China Standard and Metrology Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China

Scene graphs of point clouds help to understand object-level relationships in the 3D *** graph generation methods work on 2D structured data,which cannot be used for the 3D unstructured point cloud *** point-cloud-based methods generate the scene graph with an additional graph structure that needs labor-intensive manual *** address these problems,we explore a method to convert the point clouds into structured data and generate graphs without given ***,we cluster points with similar augmented features into groups and establish their relationships,resulting in an initial structural representation of the point ***,we propose a Dynamic Graph Generation Network(DGGN)to judge the semantic labels of targets of different *** dynamically splits and merges point groups,resulting in a scene graph with high *** show that our methods outperform other baseline *** output reliable graphs describing the object-level relationships without additional manual labeled data.

关键词： scene graph generation structural representation point cloud

Surface-confined persistent luminescence with amplified FRET efficiency for cell-cell communication monitoring

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Science China Chemistry 2025年

作者： Ziyun Miao Wenjing Dai Yubin Jin Bing qi Jiayi Chen Lingling qiu Yurong Wei Jie Wang The Key Lab of Health Chemistry&Molecular Diagnosis of Suzhou College of ChemistryChemical Engineering&Materials ScienceSoochow University

Microbial communication monitoring is vital for understanding the mechanisms beneath gut microbiota equilibrium, infections,and biomanufacturing. Herein, we reported monitoring bacterial communication by surface-confined persistent ***, we constructed core-shell structured Zn1.4Ga1.2Ge0.4O4@Zn1.4Ga1.2Ge0.4O4:Cr（ZGGO@ZGGO:Cr） persistent luminescence nanoparticles（PLNPs） with amplified FRET efficiency for the detection of azoreductase（AzoR） that participates in bacterial communication. ZGGO@ZGGO:Cr nanoparticles were functionalized with an azo black hole quencher（ZGGO@ZGGO:Cr-BHQ-3）. Due to the proximity of surface-confined persistent luminescence with the surface-bound BHQ-3,ZGGO@ZGGO:Cr-BHQ-3 exhibited a FRET efficiency up to 1.6 times that of traditional ZGGO:Cr-BHQ-3. Further, the specific catalytic reduction of azo bonds in BHQ-3 by bacterial extracellular AzoR recovers the persistent luminescence of ZGGO@ZGGO:Cr. ZGGO@ZGGO:Cr-BHQ-3 displayed superior sensitivity and speed in detecting extracellular AzoR over ZGGO:Cr-BHQ-3, attributed to its surface-confined persistent luminescence. We found that the peak secretion of AzoR occurs during the exponential growth period of bacteria including S. aureus and E. coli based on the persistent luminescence recovery rate of ZGGO@ZGGO:Cr-BHQ-3. Furthermore, ZGGO@ZGGO:Cr-BHQ-3 was used to probe the communication between different bacterial species. R. palustris is a kind of lycopene-production bacteria. We found that the cohabitation of R. palustris and S. putrefaciens boosted both AzoR secretion and lycopene production. Moreover, the secretion and activity of AzoR positively correlated with lycopene production, suggesting that AzoR may participate in the communication between R. palustris and S. putrefaciens to promote lycopene production. This study offers a robust method to enhance PLNP-based biosensing sensitivity and provides a promising strategy for microbial communication monitoring.

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