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Few-shot working condition recognition of a sucker-rod pumping system based on a 4-dimensional time-frequency signature and meta-learning convolutional shrinkage neural network

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Petroleum Science 2023年第2期20卷 1142-1154页

作者： Yun-Peng He chuan.Zhi Zang Peng Zeng Ming-Xin wang Qing-Wei Dong Guang-Xi wan Xiao-Ting Dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyangLiaoning 110016China Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyangLiaoning 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyangLiaoning 110169China University of Chinese Academy of Sciences Beijing100049China Shenyang University of Technology ShenyangLiaoning 110870China School of Automation and Electrical Engineering Shenyang Ligong UniversityShenyangLiaoning 110159China

The accurate and intelligent identification of the working conditions of a sucker-rod pumping system is necessary. As onshore oil extraction gradually enters its mid-to late-stage, the cost required to train a deep learning working condition recognition model for pumping wells by obtaining enough new working condition samples is expensive. For the few-shot problem and large calculation issues of new working conditions of oil wells, a working condition recognition method for pumping unit wells based on a 4-dimensional time-frequency signature (4D-TFS) and meta-learning convolutional shrinkage neural network (ML-CSNN) is proposed. First, the measured pumping unit well workup data are converted into 4D-TFS data, and the initial feature extraction task is performed while compressing the data. Subsequently, a convolutional shrinkage neural network (CSNN) with a specific structure that can ablate low-frequency features is designed to extract working conditions features. Finally, a meta-learning fine-tuning framework for learning the network parameters that are susceptible to task changes is merged into the CSNN to solve the few-shot issue. The results of the experiments demonstrate that the trained ML-CSNN has good recognition accuracy and generalization ability for few-shot working condition recognition. More specifically, in the case of lower computational complexity, only few-shot samples are needed to fine-tune the network parameters, and the model can be quickly adapted to new classes of well conditions.

关键词： Few-shot learning Indicator diagram Meta-learning Soft thresholding Sucker-rod pumping system Time–frequency signature Working condition recognition

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Electrosynthesis,Characterization and Optical Sensing Application of Amino Acid Functionalized Polyfluorene

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Chinese Journal of Polymer Science 2016年第2期34卷 229-241页

作者： Hui Zhang Ge Zhang 徐景坤文阳平 wan-chuan.Ding Jie Zhang Shou-li Ming Shi-jie Zhen Jiangxi Key Laboratory of Organic Chemistry Jiangxi Science and Technology Normal UniversityNanchang 330013China Key Laboratory of Applied Chemistry Jiangxi Agricultural UniversityNanchang 330045China

An amino acid side chain functionalized polyfluorene derivative poly[N-（9-fluorenylmethoxycarbonyl）-glycine] （P9FG） was facilely electrosynthesized and characterized, and the structure, properties and optical sensing application of the obtained polymer were described and discussed. The electropolymerization occurred at C2 and C7 positions of fluorene units, and amino acid side chain groups were not cleaved from polyfluorene backbone in mixed electrolytes of boron trifluoride diethyl etherate and dichloromethane. Thermal analysis demonstrated good thermal stability of P9FG. Fluorescent spectra indicated that P9FG was a good blue light emitting material that could be employed as optical sensors. The soluble P9FG as a turn-off fluorescent sensor could realize the detection of Fe^3＋, Cu^2＋ and Cr2O7^2-, respectively. In addition, P9FG as a turn-off ultraviolet sensor could realize the detection of Cu^2＋ while as turn-on ultraviolet sensors could also realize the determination of Fe^3＋ and Cr2072-, respectively. All results indicate that P9FG is a promising candidate for optical sensing.

关键词： Conjugated polymers Polyfluorene derivatives Electropolymerization Optical sensors Metal ions.

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Structure Evolution and Electrochemical Performance of Al_2O_3-coated LiNi_(0.4)Co_(0.2)Mn_(0.4)O_2 During Charge-discharge Cycling

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Chemical Research in Chinese Universities 2012年第4期28卷 686-690页

作者： LIU Hao-han ZHANG Jian LOU Yu-wan YANG chuan.zheng XIE Xiao-hua XIA Bao-jia Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 200050P.R.China

Several lithium-ion batteries of 18650-type were assembled with pristine or Al2O3-coated LiNi0.4Co0.2Mn0.4O2（NCM） as cathode material and mesocarbon microbeads（MCMB） as anode *** cycling performance of the batteries was examined under 25 °C at a 2C rate within a potential range of 2.75―4.20 *** changes of the crystal structure,the lattice parameter,the mean crystallite size,and the mean micro-strain of pristine NCM and Al2O3-coated NCM during the charge-discharge cycling were determined by X-ray diffraction（XRD）.The results indicate that the bulk structure of Al2O3-coated NCM is more stable than that of pristine NCM,which leads to the better cycling performance of Al2O3-coated NCM compared to that of pristine NCM.

关键词： LiNi0.4Co0.2Mn0.4O2 Al2O3-coated Cycling performance Bulk structure

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Effective VTeO/SBA-15 Catalyst Prepared by Precursor Method for the Selective Oxidation of Propane to Acrolein

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Chemical Research in Chinese Universities 2008年第6期24卷 793-797页

作者： FENG Mao-ying HUANG chuan.jing WENG Wei-zheng wan Hui-lin XU Qin ZHOU Zhao-hui College of Chemistry and Chemical Engineering State Key Laboratory for Physical Chemistry of Solid Surface National Engineering Laboratory for Green Chemical Productions of Alcohols Ethers and Esters Xiamen University Xiamen 361005 P. R. China

Precursor decomposition was used for the preparation of VTeO/SBA-15 catalyst for the selective oxidation of propane to acrolein. The catalyst shows a better performance compared with those prepared by conventional impregnant method. A yield of 9.3% of acrolein was achieved with 2% V loadings at 500 ℃. XRD, N2-adsorption, H2-TPR, Py-IR and XPS measurements were used to unclose the relationship between the structure and performance of the catalyst.

关键词： Acrolein Propane Vanadium catalyst Precursor decomposition

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A Lattice Study of the Glueball Spectrum

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Chinese Physics Letters 2001年第2期18卷 187-189页

作者： LIU chuan Department of Physics Peking UniversityBeijing 100871

The glueball spectrum is studied using an improved gluonic action on asymmetric lattices in the pure SU(3)lattice gauge *** smallest spatial lattice spacing is about 0.08fm which makes the extrapolation to the continuum limit more *** our lattice results to physical units using the scale set by the static quark potential,We obtain the following results for the glueball masses:MG(0^(++))=1730(90)MeV for the scalar glueball and MG(2^(++))=2400(95)MeV for the tensor glueball.

关键词： theory lattice smallest

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DEM simulations of die filling during pharmaceutical tabletting

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Particuology 2008年第6期6卷 412-418页

作者： chuan.Yu Wu School of Chemical Engineering University of Birmingham Edgbaston Birmingham B15 2TT UK

The flow behaviour of powders from a stationary shoe into a moving die, which mimics the die filling process in a rotary tablet press, was analysed using a discrete element method （DEM）, in which 2D irregular shaped particles were considered. The influence of the particle shape, size and size distribution, the number of particles used in the simulation, the initial height of powder bed in the shoe, and the filling speed on the average mass flow rate and the critical filling speed （the highest speed at which the die can be completely filled） were explored. It has been found that a maximum flow rate is obtained at the critical filling speed for all systems investigated and poly-disperse systems have higher mass flow rates and higher critical filling speeds than mono-disperse systems. In addition, the powder with particles which can tessellate generally has a lower filling rate and a lower critical titling speed.

关键词： DEM Die filling Tabletting Powder compaction Mass flow rate Critical filling speed

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Symmetry Breaking in Finite Volume

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Chinese Physics Letters 2000年第3期17卷 180-181页

作者： LIU chuan Department of Physics Peking UniversityBeijing 100871

Spontaneous symmetry breaking is a cooperative phenomenon for systems with inGnitely many degrees of freedom and it plays an essential role in quantum Held *** O(N)model is studied within the Hamiltonian approach using an adiabatic *** is shown that the low-lying spectrum of the system in the broken phase can be understood by using the adiabatic^or Born-Oppenheimer approximation,which turns out to become an expansion in the inverse power of *** the infinite volume limit,the symmetry is broken while in the finite volume the slow rotation of the zero-momGntum mode restores the symmetry and gives rise to the rotator spectrumf which has been observed in realistic Monte Carlo simulations.

关键词： symmetry adiabatic spectrum

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Simulating Strongly Correlated Electron Systems with Hybrid Monte Carlo

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Chinese Physics Letters 2000年第8期17卷 547-548页

作者： LIU chuan Department of Physics Peking UniversityBeijing 100871

Using the path integral representation,the Hubbard and the periodic Anderson model on D-dimensional cubic lattice are transformed into field theories of fermions in D+1 *** theories at half-filling possess a positive ... 详细信息

关键词： method Strongly theories

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Sunspot rotation and magnetic transients associated with flares in NOAAAR 11429

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Research in Astronomy and Astrophysics 2017年第8期17卷 47-56页

作者： Jian-chuan.Zheng Zhi-Liang Yang Jian-Peng Guo Kai-Ming Guo Hui Huang Xuan Song Wei-Xing wan Department of Astronomy Beijing Normal University Beijing 100875 China Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy ofSciences Beijing 100029 China College of Earth Sciences University of Chinese Academy of Sciences Beijing 100049 China

We analyze sunspot rotation and magnetic transients in NOAA AR 11429 during two X-class(X5.4 and X1.3)flares using data from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory.A large leading sunspot with positive magnetic polarity rotated *** expected,the rotation was significantly affected by the two *** transients induced by the flares were clearly evident in the sunspots with negative *** were moving across the sunspots with speed of order 3-7 km ***,the trend of magnetic flux evolution in these sunspots exhibited changes associated with the *** results may shed light on understanding the evolution of sunspots.

关键词： sunspots—Sun rotation—Sun magnetic fields

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Zircon and Monazite Ages Constraints on Devonian Magmatism and Granulite-Facies Metamorphism in the Southern Qaidam Block:Implications for Evolution of Proto-and Paleo-Tethys in East Asia

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Journal of Earth Science 2018年第5期29卷 1132-1150页

作者： Jin Ba Lu Zhang chuan.He Neng-Song Chen Timothy M.Kusky Qinyan wang Yusheng wan Xiaoming Liu School of Earth Sciences China University of GeosciencesWuhan 430074China College of Earth Science Chengdu University of TechnologyChengdu 610059China Sichuan.Institute of Geological Survey Chengdu 610081China Center for Global Tectonics China University of GeosciencesWuhan 430074China Beijing SHRIMP Center Beijing 100037China State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069China

High-temperature magma generation process and granulite-facies metamorphism can provide important information about mantle-crustal interaction and tectonic evolution. The strongly peralu- minous monzonite pluton, the Jinshuikou cordierite granite on the southern margin of the Qaidam Block, can provide important information about the mantle-crustal interaction and constraints on tectonic tran- sition from Proto-Tethys to Paleo-Tethys. This pluton develops enclaves of mafic granulite, amphibolite and quartzofeldspathic rocks, and is cut by massive monzonitic leuco-granite veins. Zircon and monazite U-Pb dating for the cordierite granite, the granulite enclaves and a massive monzonitic leuco-granite vein reveal that the cordierite granitic magma was generated from Mesoproterozoic continental crust with protolith derived from a provenanee that was composed of 〉2.8 Ga old recycled crustal materials and re- corded a -1.7 Ga magmatic event. The continental crust underwent low-pressure granulite-facies metamorphism at -380 Ma ago, whereas the cordierite granite magmas was generated and emplaced during 380 Ma, followed by intrusion of the massive monzonitic leuco-granite vein at circa 370-330 Ma. These data suggest that after the final closure of Proto-Tethys Ocean spreading along the southern Qaidam Block at -420 Ma, break-off of the subducted slab or delamination of the lower crustal base and upwelling of the asthenospheric mantle beneath the southern Qaidam Block occurred before the Mid-Devonian, and that the initiation of the Paleo-Tethys tectonics might initiate near the end of Early-Carboniferous in the East Kunlun-Qaidam region, East Asia.

关键词： zircon and monazite U-Pb geochronology cordierite peraluminous granite low pressure granulite Proto- and Paleo-Tethys evolution East Kunlun-Qaidam.

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