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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

Pure spin polarized transport based on Rashba spin orbit interaction through the Aharonov Bohm interferometer embodied four-quantum-dot ring

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Chinese Physics B 2013年第4期22卷 420-428页

作者：吴丽君韩宇 School of Science Shenyang Ligong University Department of Physics Liaoning University

The spin-polarized linear conductance spectrum and current–voltage characteristics in a four-quantum-dot ring embodied into Aharonov–Bohm （AB） interferometer are investigated theoretically by considering a local Rashba spin–orbit interaction. It shows that the spin-polarized linear conductance and the corresponding spin polarization are each a function of magnetic flux phase at zero bias voltage with a period of 2π, and that Hubbard U cannot influence the electron transport properties in this case. When adjusting appropriately the structural parameter of inter-dot coupling and dot-lead coupling strength, the electronic spin polarization can reach a maximum value. Furthermore, by adjusting the bias voltages applied to the leads, the spin-up and spin-down currents move in opposite directions and pure spin current exists in the configuration space in appropriate situations. Based on the numerical results, such a model can be applied to the design of a spin filter device.

关键词： quantum dot ring Rashba spin–orbit interaction spin-polarized transport "bound states in the continuum" phenomena bias voltage Aharonov–Bohm interferometer

Phase field modeling of dendrite growth

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Acta Metallurgica Sinica(English Letters) 2009年第3期22卷 197-201页

作者： Yutuo ZHANG Chengzhi WANG Dianzhong LI Yiyi LI shenyang ligong university Shenyang 110168 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Single dendrite and multi-dendrite growth for Al-2 mol pct Si alloy during isothermal solidification are simulated by phase field method. In the case of single equiaxed dendrite growth, the secondary and the necking phenomenon can be observed. For multi-dendrite growth, there exists the competitive growth among the dendrites during solidification. As solidification proceeds, growing and coarsening of the primary arms occurs, together with the branching and coarsening of the secondary arms. When the diffusion fields of dendrite tips come into contact with those of the branches growing from the neighboring dendrites, the dendrites stop growing and being to ripen and thicken.

关键词： Phase field modeling Dendrite growth Al-Si alloy Isothermal solidification

Nanocarbon-based metal-free and non-precious metal bifunctional electrocatalysts for oxygen reduction and oxygen evolution reactions

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Journal of Energy Chemistry 2021年第7期30卷 610-628页

作者： Yansong Zhu Bingsen Zhang Faculty of Pharmacy Shenyang Pharmaceutical UniversityShenyang 110016LiaoningChina shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016LiaoningChina

The oxygen reduction/evolution reactions(ORR/OER) are a key electrode process in the development of electrochemical energy conversion and storage devices,such as metal-air batteries and reversible fuel *** search for low-cost high-performance nanocarbon-based metal-free and non-precious metal bifunctional electrocatalysts for ORR/OER alternatives to the widely-used noble metal-based catalysts is a research *** review aims to outline the opportunities and available options for these nanocarbon-based bifunctional *** discussion of some current scientific issues,we summarize the development and breakthroughs of these *** we provide our perspectives on these issues and suggestions for some areas in the further *** hope that this review can improve the interest in nanocarbon-based metal-free and non-precious metal bifunctional electrocatalysts for ORR/OER.

关键词： Nanocarbon-based Oxygen reduction/evolution Bifunctional electrocatalyst Metal-free Non-precious metal

Carbon nanotube prepared from carbon monoxide by CVD method and its application as electrode materials

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Rare Metals 2006年第z2期25卷 73-76页

作者： AN Yuliang YUAN Xia CHENG Shinan GEN Xin Materials Science and Engineering College Shenyang Ligong University Shenyang 110168 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Materials Science and Engineering College Shenyang Ligong University Shenyang 110168 China Materials Science and Engineering College Shenyang Ligong University Shenyang 110168 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Carbon nanotubes with larger inner diameter were synthesized by the chemical vapor deposition of carbon monoxide (CO) on iron catalyst using H2S as promoting agent. It is found that the structure and morphology of carbon nanotubes can be tailored, to some degree, by varying the experimental conditions such as precursor components and process parameters. The results show that the presence of H2S may play key role for growing Y-branched carbon nanotubes. The products were characterized by SEM, TEM, and Raman spectroscopy, respectively. Furthermore, the obtained carbon nanotubes were explored as electrode materials for supercapacitor.

关键词： CNTs preparation CVD CO supercapacitor

Alkaloid Dimers Isolated from Thalictrum baicalense Have Antitumor Activities

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Chinese Journal of Chemistry 2022年第15期40卷 1831-1841页

作者： Jingjing Xue Yuetong Wang Fangshen Liu Hangao Yang Bin Lin Zhanlin Li Yongkui Jing Dahong Li Huiming Hua Key Laboratory of Structure-Based Drug Design&Discovery Ministry of EducationShenyang Pharmaceutical UniversityShenyangLiaoning 110016China School of Traditional Chinese Materia Medica Shenyang Pharmaceutical UniversityShenyangLiaoning 110016China School of Pharmaceutical Engineering Shenyang Pharmaceutical UniversityShenyangLiaoning 110016China Wuya College of Innovation Shenyang Pharmaceutical UniversityShenyangLiaoning 110016China

Comprehensive Summary A pair of heterodimeric isoquinoline alkaloid enantiomers,(+)thaliberberine A,five new thalifaberine-type aporphine-benzylisoquinoline(ABl)alkaloids,thalicultratines M-Q,and thirteen known analogues were isolated from the roots of Thalictrum baicalense *** *** structures were determined by extensive spectroscopic methods and ECD *** A featuring a novel carbon skeleton coupled by two different classes of isoquinoline alkaloids,protoberberine and phthalidoisoquinoline,represents the first natural product with the berberine skeleton substituted at *** biosynthetic routes of 1 are proposed.

关键词： Thalictrum baicalense Heterodimeric isoquinoline alkaloid Thalifaberine-type ABI alkaloids Antitumor activity Apoptosis

Design, Synthesis and Antifungal Activity of Benzofuran and Its Analogues

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Chinese Journal of Chemistry 2019年第12期37卷 1245-1250页

作者： Hang Xu Zhuang Hou Zhen Liang Meng-Bi Guo Xin Su Chun Guo School of Pharmaceutical Engineering Shenyang Pharmaceutical UniversityShenyangLiaoning 110016China School of life sciences and biological pharmacy Shenyang Pharmaceutical UniversityShenyangLiaoning 110016China

Summary of main observation and conclusion Benzofuran has antifungal activity as the inhibitor of ***-nine novel benzofuran-semicarbazide hybrids were designed and synthesized by principle of drug *** this basis,the benzofuran ring was simplified to a resorcinol structure,and sixteen novel 1,3-dialkoxybenzene-semicarbazide hybrids were designed and *** structures of the target compounds were characterized by HRMS and *** in vitro antifungal activity of target compounds was evaluated using the microdilution broth method against eight strains of pathogenic fungi with fluconazole as positive *** to the results of the target compounds,structure-activity relationship(SAR)is *** inhibitory activity against the tested strains of simplified compounds(K01-K16)has different levels improvement compared with compounds Z01-Z29.K01-K16 showed significant antifungal activities against ***,***,and sensitive *** ***,compounds Z20,Z22,K10,K11 and K16 also displayed different activities against two fluconazole-resistance strains that were isolated from AIDS *** minimal inhibitory concentration(MIC)values against fluconazole-resistant strains were in the range of 2-8μg/mL and 4-32μg/mL,***,molecular docking was performed to investigate the binding affinities and interaction modes between the target compound and N-myristoyltransferase.

关键词： simplified furan azide

Macro Meso Response and Stress Wave Propagation Characteristics of MCT High-Voltage Switch Under Shock load

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Defence Technology（防务技术） 2024年第2期32卷 317-335页

作者： Yuyang Guo Chuang Chen Ruizhi Wang Enling Tang Key Laboratory of Transient Physical Mechanics and Energy Conversion Materials of liaoning Province Shenyang Ligong UniversityShenyang110159LiaoningChina

In order to study the dynamic and electrical coupling response characteristics of Metal Oxide Semiconductor Controlled Thyristor(MCT)high-voltage switch under the synergic action of mechanical load and high voltage,the separated Hopkinson pressure bar(SHPB)test system was used to simulate different impact load environments,and combined with the multi-layer high-voltage ceramic capacitor charging and discharging system,the instantaneous electrical signals of MCT high-voltage switch were *** with numerical simulation and theoretical analysis,the failure mode and stress wave propagation characteristics of MCT high voltage switch were *** mechanical and electrical coupling response characteristics and failure mechanism of MCT high voltage switch under dynamic load were revealed from macroscopic and microscopic *** results show that the damage modes of MCT high-voltage switches can be divided into non-functional damage,recoverable functional damage,non-recoverable damage and structural *** to the gap between the metal gate and the oxide layer,the insulating oxide layer was *** placing for a period of time,the elastic deformation of the metal gate partially recovered and the accumulated charge disappeared,which induced the recoverable functional damage failure of the *** addition,obvious cracks appeared on both sides of the monocrystalline silicon inside the MCT high-voltage switch,leading to unrecoverable damage of the device.

关键词： MCT Impact load Failure analysis Stress wave Numerical simulation

Microstructural features and precipitation behavior of Ti,Nb and V microalloyed steel during isothermal processing

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Journal of Iron and Steel Research International 2019年第1期26卷 102-111页

作者： Qi Zhou Zhuang Li Zhan-shan Wei Di Wu Jin-yu Li Zhen-yao Shao School of Environment and Chenlical Engineering Shenyang Ligong UniversityShenyang 110159LiaoningChina College of Materials Science and Engineering Shenyang Aerospace UniversityShenyang 110136LiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110004LiaoningChina

Thermal simulations of Ti,Nb and V microalloyed steel were conducled using a thermomechanical simulator,and the microstructural evolution and the precipitation behavior during isothermal processing were *** results show that with increasing holding time,the microstructural constituents change from the martensite and bainitic ferrites to granular bainite and polygonal *** maximum hardness is obtained for the specimen after isothermal holding for 5s due to the martensite strengthening *** hardness of the specimen decreases after isothermal holding for 10s,because the strengthening contribution of fine dispersed precipitates becomes *** hardness values of the specimens increase and then remain high after isothermal holding for 60 and *** is attributed to the contribution of the interphase precipitation hardening to the hardness of the studied *** precipitates in the specimen are coarsened after isothermal holding for 3600s,even though the coarsening is not *** precipitates are fee(***)(N.C)particles and belong to the MX-type *** beneficial effects of precipitation strengthening are *** hardness decreases to a minimum hardness value due to the presence of large amounts of polygonal ferrite after isothermal holding for *** coarse precipitates are the primary origin of the hardness decrease.

关键词： Microalloyed steel Isothermal holding time Microstructural constituent Precipitation Hardness