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China Ocean Engineering 2024年第2期38卷 233-246页

作者： DING Xin-dong wang shu-qing LIU Wen-cheng YE Xiao-han College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China Department of Marine Technology Norwegian University of Science and Technology(NTNU)Trondheim NO-7491Norway

The collapse pressure is a key parameter when RTPs are applied in harsh deep-water *** investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are *** the numerical simulations,the eigenvalue analysis and Riks analysis are combined,in which the Hashin failure criterion and fracture energy stiffness degradation model are used to simulate the progressive failure of composites,and the“infinite”boundary conditions are applied to eliminate the boundary *** for the hydrostatic pressure tests,RTP specimens were placed in a hydrostatic chamber after filled with *** has been observed that the cross-section of the middle part collapses when it reaches the maximum *** collapse pressure obtained from the numerical simulations agrees well with that in the ***,the applicability of NASA SP-8007 formula on the collapse pressure prediction was also *** has a relatively greater difference because of the ignorance of the progressive failure of *** the parametric study,it is found that RTPs have much higher first-ply-failure pressure when the winding angles are between 50°and 70°.Besides,the effect of debonding and initial ovality,and the contribution of the liner and coating are also discussed.

关键词： reinforced thermoplastic pipes post-buckling behavior progressive failure of composites debonding initial ovality

基于黏菌优化算法的水轮机调节系统控制参数优化研究

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水电能源科学 2024年第7期42卷 188-192,159页

作者：李青珏王淑青邹屹东湖北工业大学电气与电子工程学院湖北武汉430068 武汉大学动力与机械学院湖北武汉430072

为改善水轮机调节系统的控制性能,基于等效电路法建立了全流道引水系统数学模型,结合水轮机、发电机及调速器模型构建水轮机调节系统的整体模型。在此基础上,引入黏菌优化算法对水轮机调速器PID参数实施优化。最后,在不同工况下进行仿真... 详细信息

为改善水轮机调节系统的控制性能,基于等效电路法建立了全流道引水系统数学模型,结合水轮机、发电机及调速器模型构建水轮机调节系统的整体模型。在此基础上,引入黏菌优化算法对水轮机调速器PID参数实施优化。最后,在不同工况下进行仿真,仿真结果表明,SMA算法收敛速度快,寻优能力强,基于此算法的调速器使水轮机调节系统具有更好的动态稳定性,研究结果为实际工程应用提供了参考。

关键词： SMA算法水轮机调速系统等效电路法控制参数优化

基于IMF-MFDE和GRU的水电机组故障诊断

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水电能源科学 2024年第4期42卷 173-177页

作者：朱文鑫王淑青湖北工业大学电气与电子工程学院湖北武汉430068

针对水电机组振动信号非平稳、非线性及强噪声的特点,提出了一种IMF多尺度波动散布熵(MFDE)结合门控循环单元(GRU)的故障诊断方法。首先,采用跳蛛优化算法(JSOA)寻找变分模态分解(VMD)最优参数,达到振动信号最佳分解降噪效果;其次,对分... 详细信息

针对水电机组振动信号非平稳、非线性及强噪声的特点,提出了一种IMF多尺度波动散布熵(MFDE)结合门控循环单元(GRU)的故障诊断方法。首先,采用跳蛛优化算法(JSOA)寻找变分模态分解(VMD)最优参数,达到振动信号最佳分解降噪效果;其次,对分解得到的本征模态函数(IMF)进行重构,计算有效IMF的多尺度波动散布熵(MFDE)作为故障特征向量;最后,将特征向量输入GRU构建水电机组故障识别器。所提方法对实际水电站机组故障样本数据的故障识别率达97.83%,验证了该方法的有效性。

关键词：水电机组振动信号故障诊断跳蛛优化算法变分模态分解多尺度波动散布熵

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基于小波包分解与CEEMDAN能量熵的水电机组振动信号特征提取

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水电能源科学 2024年第6期42卷 198-202,216页

作者：王淑青罗平章胡文庆柯洋洋张家豪湖北工业大学电气与电子工程学院湖北武汉430068 武汉大学动力与机械学院湖北武汉430072

针对水电机组振动信号非平稳、非线性及噪声问题,提出一种基于自适应噪声完备经验模态分解(CEEMDAN)与能量熵结合的特征提取方法,首先对采集的振动信号进行小波包降噪处理,然后对降噪后信号进行CEEMDAN分解,运用相关系数法筛选有效固有... 详细信息

针对水电机组振动信号非平稳、非线性及噪声问题,提出一种基于自适应噪声完备经验模态分解(CEEMDAN)与能量熵结合的特征提取方法,首先对采集的振动信号进行小波包降噪处理,然后对降噪后信号进行CEEMDAN分解,运用相关系数法筛选有效固有模态函数(IMF)并计算其能量熵,由此构建特征向量集,最后将其输入到海洋捕食者优化支持向量机算法(MPA-SVM)进行模式识别。基于模拟信号、实测信号验证所提特征提取方法的有效性,并与其他方法作对比。结果表明,基于小波包分解与CEEMDAN能量熵的特征提取方法能准确提取特征,有效区分机组不同状态,为工程领域提供了应用价值。

关键词：水电机组振动信号小波包分解自适应噪声完备经验模态分解能量熵特征提取

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地学类“测量学”虚拟仿真实践教学体系建设探讨

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教育教学论坛 2024年第21期 13-16页

作者：李丽华陶象武李淑慧王淑晴土地科学技术学院北京100083

在高等教育信息化建设背景下,基于虚拟仿真技术的地学类“测量学”实践教学体系有待完善。综合测绘新技术,融合地学类专业的差异,分别设计了技术基础模块、设计与综合模块和创新模块等模块;并在此基础上探讨了实践教学方法、教学管理、... 详细信息

在高等教育信息化建设背景下,基于虚拟仿真技术的地学类“测量学”实践教学体系有待完善。综合测绘新技术,融合地学类专业的差异,分别设计了技术基础模块、设计与综合模块和创新模块等模块;并在此基础上探讨了实践教学方法、教学管理、实践教学评价和实践教学保障等内容,进而形成了具有地学特色的“测量学”虚拟仿真实践教学体系。该实践教学体系以学生为中心,为不同专业学生提供多项选择,培养学生的实践能力及复杂工程能力,进而提升大地学专业学生的综合创新能力。

关键词：测量实践教学地学类专业虚拟仿真模块化

Modal Parameters Identification of A Real Offshore Platform From the Response Excited by Natural Ice Loading

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China Ocean Engineering 2020年第4期34卷 558-570页

作者： YANG Wen-long wang shu-qing ESI North America Farmington HillsMI 48334USA Shandong Provincial Key Lab of Ocean Engineering Ocean University of ChinaQingdao 266100China

This paper investigates the possibility of utilizing response from natural ice loading for modal parameter identification of real offshore *** test platform is the JZ20-2 MUQ jacket platform located in the Liaodong Bay,China.A field experiment is carried out in winter season,as the platform is excited by floating *** feasibility is demonstrated by the acceleration response of two different *** the SSI-data method,the modal frequencies and damping ratios of four structural modes can be successfully identified from both *** estimated information from both segments is almost identical,which demonstrates that the modal identification is ***,by taking the Jacket platform as a benchmark,the numerical performance of five popular time-domain EMA methods is systematically compared from different *** comparisons are categorized as:(1)stochastic methods versus deterministic methods;(2)high-order methods versus low-order methods;(3)data-driven versus covariance-driven stochastic subspace identification methods.

关键词： modal identification experimental modal analysis offshore platform ambient excitation natural ice loading comparative study

Robust model predictive control for discrete uncertain nonlinear systems with time-delay via fuzzy model

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第10期7卷 1723-1732页

作者： SU Cheng-li wang shu-qing National Laboratory of Industrial Control Technology Institute of Advanced Process Control Zhejiang University Hangzhou 310027 China

An extended robust model predictive control approach for input constrained discrete uncertain nonlinear systems with time-delay based on a class of uncertain T-S fuzzy models that satisfy sector bound condition is presented. In this approach, the minimization problem of the “worst-case” objective function is converted into the linear objective minimization problem in- volving linear matrix inequalities (LMIs) constraints. The state feedback control law is obtained by solving convex optimization of a set of LMIs. Sufficient condition for stability and a new upper bound on robust performance index are given for these kinds of uncertain fuzzy systems with state time-delay. Simulation results of CSTR process show that the proposed robust predictive control approach is effective and feasible.

关键词：模糊控制时延模型预测控制 LMIs MPC 鲁棒性

Predictive control of a class of bilinear systems based on global off-line models

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第12期7卷 1984-1988页

作者： ZHANG Ri-dong wang shu-qing Institute of Advanced Process Control National Key Laboratory of Industrial Control Technology Zbejiang University Hangzhou 310027 China

A new multi-step adaptive predictive control algorithm for a class of bilinear systems is presented. The structure of the bilinear system is converted into a simple linear model by using nonlinear support vector machine (SVM) dynamic approximation with analytical control law derived. The method does not need on-line parameters estimation because the system’s internal model has been transformed into an off-line global model. Compared with other traditional methods, this control law reduces on-line parameter estimating burden. In addition, its overall linear behavior treating method allows an analytical control law available and avoids on-line nonlinear optimization. Simulation results are presented in the article to illustrate the efficiency of the method.

关键词：双线性系统模式预控制 MPC 适应控制

Dual modification of LiNi0.83Co0.11Mn0.06O2 cathode materials by K+ doping and Li3PO4 coating for lithium ions batteries

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Rare Metals 2024年第7期43卷 3007-3018页

作者： Wei Xiao Jia-Le wang Zhi-Cheng Yi Cheng-Jin Liu Chang Miao Yu Xin shu-qing Nie College of Chemistry and Environmental Engineering Yangtze University

Li3PO4@Li0.99K0.01Ni0.83Co0.11MnO.06O2（NCM-KP） cathode powders are synthesized via K+doping in calcination processes and H3PO4coating in sol-gel processes.K+precisely enters into the lattice to widen the（003） plane to 0.4746 nm with a lower cationic disordered degree of 1.87%.Moreover,the surface residual lithium salts are treated by H3PO4to generate a uniform Li3PO4coating layer of approximately 11.41 nm,which completely covers on the surface of secondary spherical particles to improve the interfacial *** 25℃,the NCM-KP electrode delivers a discharge specific capacity of 148.9 mAh·g-1with a remarkable capacity retention ratio of 84.1% after 200 cycles at 1.0C and retains a high reversible specific capacity of 154.4 mAh·g-1at *** at 1.0C and 60℃,it can maintain a reversible discharge specific capacity of 114.6 mAh·g-1with 0.21% of capacity decay per cycle after 200 cycles,which is significantly lower than 0.40% for the pristine NCM ***,the charge transfer resistance of 238.89 Ω for the NCM-KP electrode is significantly lower than 947.41 Ω for the pristine NCM one by restricting the interfacial side ***,combining K+doping and Li3PO4coating is an effective strategy to enable the significant improvement of the electrochemical property of high-nickel cathode materials,which may be mainly attributed to the widened diffusion pathway and the formed Li3PO4protective layer,thus promoting Li+diffusion rate and preventing the erosion of HF.

关键词： High-nickel cathode material Residual lithium K + doping Li 3 PO 4 coating Lithium ions battery

Designing Proportional-Integral Consensus Protocols for Second-Order Multi-Agent Systems Using Delayed and Memorized State Information

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 878-892页

作者： Honghai wang qing-Long Han the College of Information Science and Engineering State Key Laboratory of Synthetical Automation for Process IndustriesNortheastern UniversityShenyang 110819China the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourneVIC 3122Australia

This paper is concerned with consensus of a secondorder linear time-invariant multi-agent system in the situation that there exists a communication delay among the agents in the network.A proportional-integral consensus protocol is designed by using delayed and memorized state *** the proportional-integral consensus protocol,the consensus problem of the multi-agent system is transformed into the problem of asymptotic stability of the corresponding linear time-invariant time-delay *** that the location of the eigenvalues of the corresponding characteristic function of the linear time-invariant time-delay system not only determines the stability of the system,but also plays a critical role in the dynamic performance of the *** this paper,based on recent results on the distribution of roots of quasi-polynomials,several necessary conditions for Hurwitz stability for a class of quasi-polynomials are first *** allowable regions of consensus protocol parameters are *** necessary and sufficient conditions for determining effective protocol parameters are *** designed protocol can achieve consensus and improve the dynamic performance of the second-order multi-agent ***,the effects of delays on consensus of systems of harmonic oscillators/double integrators under proportional-integral consensus protocols are ***,some results on proportional-integral consensus are derived for a class of high-order linear time-invariant multi-agent systems.

关键词： Consensus protocol Hurwitz stability multi-agent systems quasi-polynomials time delay