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基于物理信息神经网络的长距离顶管施工顶力预测

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人民长江 2025年第1期56卷 147-155页

作者：李博刘宇翔陈建国杨耀红张哲河南省水利第一工程局集团有限公司河南郑州450000 华北水利水电大学水利学院河南郑州450046 河南省水圈与流域水安全重点实验室河南郑州450046

长距离顶管施工过程中,准确预测顶力是有效控制施工安全质量及进度的关键问题。基于知识数据融合的机器学习建模方法,将顶力计算物理模型与多层感知机相融合,构建了物理-数据双驱动的物理信息神经网络模型(PINN),用物理机制约束神经网... 详细信息

长距离顶管施工过程中,准确预测顶力是有效控制施工安全质量及进度的关键问题。基于知识数据融合的机器学习建模方法,将顶力计算物理模型与多层感知机相融合,构建了物理-数据双驱动的物理信息神经网络模型(PINN),用物理机制约束神经网络的训练机制,并引入改进的麻雀搜索算法(ISSA)对模型超参数取值进行优化,建立了ISSA-PINN顶管施工顶力预测模型;以河南省郑开同城东部供水工程顶管施工为例,选取524组工程实测数据验证了模型的有效性。计算结果表明:ISSA-PINN模型具有较高的预测精度,相较于单纯数据驱动模型,在测试集和新数据集中的预测性能分别提升了0.07和0.17,说明物理模型的融入对降低机器模型的过拟合风险和提高泛化能力有积极影响;相比于SSA和粒子群算法,ISSA算法寻优速度更快、适应度更好。研究结果可为顶管工程施工顶力控制提供参考。

关键词：顶管施工顶力预测物理信息神经网络(PINN) 改进麻雀搜索算法(ISSA)

Balance control of grid currents for UPQC under unbalanced loads based on matching-ratio compensation algorithm

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Journal of Modern Power Systems and Clean Energy 2018年第6期6卷 1319-1331页

作者： Xiaojun ZHAO Chunjiang zhang Xiuhui CHAI Jinlong zhang Fanqi LIU zhe zhang Department of Electrical Engineering Yanshan University Department of Electrical Engineering Technical University of Denmark

In three-phase four-wire systems, unbalanced loads can cause grid currents to be unbalanced, and this may cause the neutral point potential on the grid side to shift. The neutral point potential shift will worsen the control precision as well as the performance of the threephase four-wire unified power quality conditioner(UPQC),and it also leads to unbalanced three-phase output voltage,even causing damage to electric equipment. To deal with unbalanced loads, this paper proposes a matching-ratio compensation algorithm(MCA) for the fundamental active component of load currents, and by employing this MCA,balanced three-phase grid currents can be realized under 100% unbalanced loads. The steady-state fluctuation and the transient drop of the DC bus voltage can also be restrained. This paper establishes the mathematical model of the UPQC, analyzes the mechanism of the DC bus voltage fluctuations, and elaborates the interaction between unbalanced grid currents and DC bus voltage fluctuations;two control strategies of UPQC under three-phase stationary coordinate based on the MCA are given, and finally, the feasibility and effectiveness of the proposed control strategy are verified by experiment results.

关键词： Unified power quality conditioner(UPQC) Unbalanced loads Matching-ratio compensation Balance control DC bus voltage fluctuations

A Novel Method for Achieving Gradient Microstructure in a Cu-Al Alloy:Surface Spinning Strengthening (3S)

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Acta Metallurgica Sinica(English Letters) 2017年第3期30卷 212-217页

作者： Chuan-Xi Ren QiangWang zhen-Jun zhang Yan-Kun Zhu zhe-Feng zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Hefei 230026 China

A new designed surface strengthening method, surface spinning strengthening （3S）, was applied to achieve gradient microstructure in the surface layer of a Cu-11 at.%A1 alloy. According to the level of grain refinement, the gradient microstructure can be divided into four zones, including nanoscale grain zone, ultra-fine grain zone, fine grain zone and coarse grain zone from the surface to the matrix. Meanwhile, a plenty of grain boundaries and twin boundaries were introduced to inhibit the dislocation motion in the surface layer during the plastic deformation process. Consequently, the hardened layer with a microhardness gradient and high residual compressive stress was produced on the samples, and the yield strength of the Cu-11 at.%A1 alloy was effectively improved after 3S processing due to the strengthening effect caused by the gradient microstructurc.

关键词： Cu-AI alloy Surface spinning strengthening (3S) Strength Microhardness Gradientmicrostructure

Preparation and Characterization of SiO2/Co and C/Co Nanocomposites as Fisher-Tropsch Catalysts for CO2 Hydrogenation

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Chemical Research in Chinese Universities 2018年第4期34卷 635-642页

作者： HAN Fuqin zhang zhe NIU Na LI Jian College of Science Northeast Forestry University Harbin 150040 P. R. China Key Laboratory of Bio-based Material Science and Technology Ministry of Education Northeast Forestry University Harbin 150040 P. R. China

To fabricate high-density cobalt-based catalysts, we first synthesized SiO]C composites via a hydrother- mad method and removed C and SiO2 by two different methods, respectively. The as-prepared SiO2 and C supports then reacted with cobalt acetylacetonate and N,N-dimethylformamide（DMF） under hydrothermal conditions to prepare SiO2/Co and C/Co nanocomposite catalysts. The catalysts were characterized by X-ray difffaction（XRD）, scanning electron microscope（SEM）, transmission electron microscopy（TEM）, inductively coupled plasma mass spectrometry（ICP）~ energy dispersive X-ray fiuoresence spectrometer（EDX）, and nitrogen adsorption. It was found that hexagonal cobalt nanocrystals were successfully integrated with the mesoporous silica or carbon nanotube supports. SEM and TEM results show that SiO2/Co composites with a hollow/mesoporous sphere structure and C/Co composites with a tubular structure have been successfully synthesized. Both composite samples show superpara- magnetism exhibiting an S-type hysteresis loop, which originated from the cobalt nanoparticles in the samples. Nitrogen adsorption/desorption curves suggest that the SiO2 and C supports have well-developed pore structures and large specific surface areas, and the loading and good dispersity of cobalt nanoparticles on the supports were proven by ICP and EDX. Moreover, the samples exhibited good and stable catalytic activity, denlonstrating that the two composites are suitable catalysts for Fischer-Tropsch CO2 hydrogenation.

关键词： Mesoporous SiO2 Carbon nanotube Cobalt based catalyst Fischer-Tropseh reaction CO2 hydrogenation

CD176 single-chain variable antibody fragment inhibits the adhesion of cancer cells to endothelial cells and hepatocytes

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Frontiers of Medicine 2016年第2期10卷 204-211页

作者： Jiangnan Liu Bin Yi zhe zhang Yi Cao Laboratory of Molecular and Experimental Pathology Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China Kunming College of Life Science University of Chinese Academy of Sciences Kunming 650223 China

CD176 （Thomsen-Friedenreich antigen） is a tumor-associated carbohydrate epitope （glycotope） functionally involved in blood spread and fiver metastasis of cancer cells by mediating the adhesion of cancer cells to endothelial cells and hepatocytes, respectively. CD176 could be a promising target for antitumor immunotherapy. We applied B lymphocytes obtained from mice immunized with CD176 antigen and constructed a phage display library. A positive clone of CD176 single-chain variable antibody fragment （scFv） was successfully screened from this library. The CD176 scFv was expressed in Escherichia coli and purified. The purified scFv can bind to the natural CD176 expressed on the surface of cancer cells. Furthermore, the CD176 scFv inhibits the adhesion of CD176＋ cancer cells to endothelial cells and hepatocytes. This CD176 scFv provides a basis for future development of recombinant CD176-specific antibodies that can be used in therapeutic application.

关键词： CD 176 Thomsen-Friedenreich antigen scFv cancer therapy adhesion metastasis

Sublethal Effects of Metaflumizone on Plutella xylostella (Lepidoptera: Plutellidae)

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Journal of Integrative Agriculture 2012年第7期11卷 1145-1150页

作者： zhang zhe LI Jian-hong GAO Xi-wu College of Plant Science & Technology Huazhong Agricultural University Wuhan 430070 P.R.China Department of Entomology China Agricultural University Beijing 100193 P.R. China

Metaflumizone is a novel sodium channel blocker insecticide, which has been registered for controling the diamondback moth （DBM）, Plutella xylostella （Lepidoptera： Plutellidae） in China. It is unavoidable for DBMs to be exposed to sublethal dose of metaflumizone in brassicaceous vegetable field. Sublethal effects of metaflumizone at LC15 （1.06 mg L-1） and LCz5 （2.03 mg L-1） on the biological characteristics were investigated. Pupation rate, pupal period and pupal weight were significantly declined comparing with the control （P=0.05） when third instar larvae were exposed to LC15 and LC25 of metaflumizone. Comparing the control group to LC15 and LC25 treatment groups, there were significant differences in the development periods of eggs, first instar larvae, pupae and total preoviposition period. The peak of age-specific fecundity in LC15 and LC25 treatment groups was lagged behind control group. Mean values of intrinsic rate of increase （rm）, net reproductive rate （R0） and finite rate of increase （λ） observed from the LCl5 and LC25 treatment groups were lower than those from the control group. But mean values of gross reproduction rate （GRR） was not different. The mean generation time （T） of the treatment groups was prolonged. Whether sublethal doses of metaflumizone could stimulate reproduction in the long term needs further investigation on continuous generations.

关键词： Plutella xylostella metaflumizone sublethal dose life table parameters

Robust Remaining Useful Life Estimation Based on an Improved Unscented Kalman Filtering Method

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Computer Modeling in Engineering & Sciences 2020年第6期123卷 1151-1173页

作者： Shenkun Zhao Chao Jiang zhe zhang Xiangyun Long State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha410082China

In the Prognostics and Health Management(PHM),remaining useful life(RUL)is very important and utilized to ensure the reliability and safety of the operation of complex mechanical ***,unscented Kalman filtering(UKF)has been applied widely in the RUL *** a degradation system,the relationship between its monitored measurements and its degradation states is assumed to be nonlinear in the conventional ***,in some special degradation systems,their monitored measurements have a linear relation with their degradation *** these special problems,it may bring estimation errors to use the UKF method ***,many uncertain factors can result in the fluctuations of the estimated results,which may have a bad influence on the RUL estimation *** a result,a robust RUL estimation approach is proposed in this paper to reduce the errors and randomness of estimation results for this kind of degradation ***,an improved unscented Kalman filtering is established utilizing the Kalman filtering(KF)method and a linear adaptive *** linear adaptive strategy is used to adjust its noise term ***,the robust RUL estimation is realized by the improved *** last,three problems are investigated to demonstrate the effectiveness of the proposed method.

关键词： Remaining useful life unscented Kalman filtering state space model

GROUP CONSENSUS FOR MULTIPLE NETWORKED EULER-LAGRANGE SYSTEMS WITH PARAMETRIC UNCERTAINTIES

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Journal of Systems Science & Complexity 2014年第4期27卷 632-649页

作者： HU Hongxiang zhang zhe YU Li YU Wenwu XIE Guangming Department of Mathematics Hangzhou Dianzi University zhejiang Provincial United Key Laboratory of Embedded Systems Department of AutomationZhejiang University of Technology Department of Mathematics Southeast University School of Electrical and Computer Engineering RMIT University Faculty of Engineering King Abdulaziz University Center for Systems and Control State Key Laboratory of Turbulence and Complex SystemsCollege of EngineeringPeking University

In this paper,a group consensus problem is investigated for multiple networked agents with parametric uncertainties where all the agents are governed by the Euler-Lagrange system with uncertain *** the group consensus problem,the agents asymptotically reach several different states rather than one consistent state.A novel group consensus protocol and a time-varying estimator of the uncertain parameters are proposed for each agent in order to solve the couple-group consensus *** is shown that the group consensus is reachable even when the system contains the uncertain ***,the multi-group consensus is discussed as an extension of the couple-group consensus,and then the group consensus with switching topology is *** results are finally provided to validate the effectiveness of the theoretical analysis.

关键词： Euler-Lagrange system group consensus multi-agent systems switching topologies.

Electronic Nose with an Air Sensor Matrix for Detecting Beef Freshness

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Journal of Bionic Engineering 2008年第1期5卷 67-73页

作者： zhe zhang Jin Tong Dong-hui Chen Yu-bin Lan Key Laboratory of Terrain-Machine Bionics Engineering （Ministry of Education China） Jilin University Changchun 130022 P. R. China Aerial Application Technology USDA-ARS-SPARC-APMRU College Station TX 77845 USA

China is one of the largest meat producing countries in the wodd. With the growing concern for food safety more attention has been paid to meat quality. The application of conventional test methods for meat quality is limited by many factors, and subjectiveness, such as longer time to prepare samples and to test. A sensor matrix was constructed with several separate air sensors, and tests were conducted to detect the freshness of the beef. The results show that the air sensors TGS2610, TGS2600, TGS2611, TGS2620 and TGS2602 made by Tianjin Figaro Electronic Co, Ltd could be used to determine the degree of freshness but TGS2442 is not suitable. This study provides a foundation for designing and making an economical and practical detector for beef freshness.

关键词： gas sensitive sensor matrix degree of beef freshness electronic nose