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Gauss optimization method for the dynamics of unilateral contact of rigid multibody systems

Acta Mechanica Sinica 2021年第3期37卷 494-506,I0003页

作者： wenli yao Liusong Yang Mingming Guo Qingdao Key Laboratory for Geomechanics and Offshore Underground Engineering School of ScienceQingdao University of TechnologyQingdao 266520China College of Pipeline and Civil Engineering China University of Petroleum(East China)Qingdao 266520China

The discontinuous dynamical problem of multi-point contact and collision in multi-body system has always been a hot and difficult issue in this *** on the Gauss’principle of least constraint,a unified optimization model for multibody system dynamics with multi-point contact and collision is *** paper presents the study of the numerical solution scheme,in which particle swarm optimization method is used to deal with the corresponding optimization *** article also presents the comparison of the Gauss optimization method(GOM)and the hybrid linear complementarity method(*** differential algebraic equations(DAEs)and linear complementarity problems(LCP)),commonly used to solve the dynamic contact problem of multibody systems with bilateral *** results illustrate that,the GOM has the same advantage of dynamical modelling with LCP and when the redundant constraint exists,the GOM always has a unique solution and so no additional processing is needed,whereas the corresponding DAE-LCP method may have singular cases with multiple solutions or no *** numerical examples,the GOM is verified to effectively solve the dynamics of multibody systems with redundant unilateral and bilateral constraints without additional redundancy *** GOM can also be applied to the optimal control of systems in the future and combined with the parameter optimization of systems to handle dynamic *** work given provides the dynamics and control of the complex system with a new train of thought and method.

关键词： Contact Collision Redundant constraint Gauss principle of least constraint Optimization method

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Optimization method for dynamics of non-holonomic system based on Gauss’ principle

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Acta Mechanica Sinica 2020年第5期36卷 1133-1141,I0004页

作者： wenli yao Liusong Yang Kewei Song Haiming Wang Qingdao Key Laboratory for Geomechanics and Offshore Underground Engineering School of ScienceQingdao University of TechnologyQingdao 266520China College of Pipeline and Civil Engineering China University of Petroleum(East China)Qingdao 266580China

The real-time control of the non-holonomic wheel robot has put forward higher requirements for the accuracy and speed of dynamical simulation,so it is necessary to study the new dynamic modeling and calculation methods adapting to modern information *** from the traditional method solving differential-algebraic equation,the objective is to establish optimization model and effective calculating scheme for dynamics of non-holonomic system based on basic dynamical *** optimization model cannot be obtained directly from the traditional Gauss'*** using Gauss'principle of variational form,this paper deduces the minimum principle in the form of generalized coordinates and quasi-coordinates,respectively,thus allowing dynamical problems of non-holonomic systems to be incorporated into the framework of solving constrained or unconstrained optimization ***,we study a numerical calculation scheme that uses an optimization algorithm for the second form of the above optimization *** an example,the dynamical problem of a differential-driven wheeled mobile-robot system is *** optimization dynamic model of a non-holonomic robot system and the calculation model of the optimization algorithm are *** theresults of the optimization calculation with the differential-algebraic equations commonly used in dynamical problem for non-holonomic system reveals that the method in this paper is superior in terms of calculation speed and can more effectively handle constraint violations without extra constraint revision needed.

关键词： Gauss'principle Non-holonomic systems-Optimization Quasi-coordinates

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Circulating current suppression for ground tied variable frequency to constant frequency converter system in aircraft

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Chinese Journal of Aeronautics 2023年第11期36卷 386-397页

作者： Wei WEI Ming HUANG wenli yao Weilin LI Xiaobin ZHANG School of Automation Northwestern Polytechnical UniversityXi’an 710072China Air Defense and Antimissile School Air Force Engineering UniversityXi’an 710100China

This paper presents a solution to the circulating current fault of aircraft power *** DC-link type Variable Frequency to Constant Frequency(VFCF)converter system is the preferred scheme to feed the constant 400 Hz load in an aircraft with a variable frequency power *** to the requirement of aircraft standards,both grounds of the rectification and inversion stage are tied to the metal frame of the *** such a tied ground,the DC bus voltage rises greatly,and a large circulating current appears in the casing as the ground,which leads to equipment failure and potential safety *** to the existing methods of circulating current fault suppression,this paper analyzes the causes of the above faults and the harmonic components of circulating current and points out the limitations of the existing ***,a Common-Mode(CM)choke-based method is proposed to provide a high impedance in the path of the CM circulating *** doing so,the circulating current can be suppressed without the additional burden of the hardware and control algorithm,which is quite friendly for quality control of mass-production ***,a simplified mathematic model of the VFCF converter system is derived to calculate the minimum inductance value reference of the CM choke,which saves the weight of passive devices to the greatest ***,simulation and experimental results are studied to verify the effectiveness of the proposed method.

关键词： Aircraft power supply Circulating current Common mode choke Power supply circuits Variable Speed Constant Frequency

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Concealed fault analysis based on the CT projection matrix

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International Journal of Mining Science and Technology 2016年第2期26卷 361-367页

作者： Yang Zhen yao wenli Ma Liuzhu Wise Lucas School of Mines China University of Mining & Technology Key Laboratory of Deep Coal Resource Mining Ministry of Education of China

This paper proposes the concept of projection curves based on the theory of CT image reconstruction to probe the internal structure of the working panel prior to formal mining of the working *** well as reducing costs,this method provides safe and efficient excavation of the working *** to the results of the numerical model and the actual working panel,the new method has been proven to be accurate in detecting the location of the fault that extends into the *** faults of the internal working panel,as well as the start and end points of the fault,can be detected by this *** practice has proven that the method is highly reliable,has a highly decisive impact on faults for coal mining,and can be used to guide the safe mining of the working panel.

关键词： Working panel Computed tomography Concealed fault Project curve

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Fracture distribution in overburden strata induced by underground mining

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Deep Underground Science and Engineering 2022年第1期1卷 58-64页

作者： wenli yao Enzhi Wang Xiaoli Liu Ran Zhou Department of Hydraulic Engineering State Key Laboratory of Hydroscience and EngineeringTsinghua UniversityBeijingChina Department of Hydraulic Engineering YSD Rail Transit Construction Company LimitedGuangzhouChina

Coal-mining activities give rise to a series of ecological environmental problems,such as ground settlement and groundwater *** fact,they are mainly caused by mining-induced ***,it is necessary to study the mining-induced fracture distribution to identify the behavior of rock mass ***,the fractures in overburden strata cannot be directly measured owing to the special ***,the majority of previous studies are based on experiments or *** this reason,this study first used a discrete element method to simulate the shape of mining-induced fractures in overburden ***,a geophysical tool of transient electromagnetic method(TEM)was used to investigate the mining-induced fracture *** on the low-resistivity anomaly area,the water-rich area in overburden strata was analyzed to be mainly caused by fracture *** the mutual authentication between numerical simulation and TEM results,the mining-induced fractures in overburden strata were *** study can enhance the understanding of mining-induced fracture distribution on the one hand and guarantee the coal mining safety on the other,thus guiding the coordinated development between coal mining and environmental protection.

关键词： groundwater seepage mining-induced fracture numerical simulation rock mass deformation TEM

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Effect of doping order on metal-free heteroatoms dual-doped carbon as oxygen reduction electrocatalyst

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Chinese Chemical Letters 2021年第2期32卷 745-749页

作者： Hui-Juan Zhang Jing Geng Chunlei Cai Zi-Feng Ma Zhong Ma wenli yao Junhe Yang School of Materials Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China Department of Chemical and Biomolecular Engineering.University of Illinois at Urbana-Champaign UrbanaIllinois 61801United States Department of Chemical Engineering Shanghai Jiaotong UniversityShanghai 200240China Department of Chemical Engineering Waterloo Institute for Nanotechnology(WIN)University of WaterlooWaterlooOntario N2L3G1Canada Jiangxi Key Laboratory of Power Battery and Material Faculty of Materials Metallurgy and ChemistryJiangxi University of Science and TechnologyGanzhou 341000China

Metal-free heteroatoms dual-doped carbon has been recognized as one of the most promising Pt/C-substitutes for oxygen reduction reaction(ORR).Herein,we optimize the preparation process by doping order of metal-free heteroatoms to obtain the best electrocatalytic performance through three types of dual-doped carbon,including XC-N(first X doping then N doping),NC-X(first N doping then X doping) and NXC(N and X doping)(X=P,S and F).XC-N has more defect than the other two indicated by Raman spectra.X-ray photoelectron spectrom(XPS) measurements indicate that N and X have been dual-doped into the carbon matrix with different doping contents and modes,Electrocatalytic results,including the potential of ORR peak(Ep),the half-wave potential,the diffusion-limiting current density mainly follows the order of XC-N>NC-X> NXC,Furthermore,the synergistic effect of second atom doping are also compared with the single doped carbon(NC,PC,SC and FC).The differences in electronegativity and atomic radius of these metal-free heteroatoms can affect the defect degree,the doping content and mode of hete roatoms on carbon matrix,induce polarization effect and space effect to affect O2 adsorption and product desorption,ultimately to the ORR electrocatalytic performance.

关键词： Oxygen reduction reaction Metal-free electrocatalyst Heteroatoms dual-doped carbon Doping order N P S and F

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四川盆地须家河组致密砂岩物源体系的控储作用

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地质科技通报 2021年第5期40卷 223-230页

作者：姚文礼长江大学工程技术学院湖北荆州434020

为明确四川盆地须家河组致密砂岩物源特征及控储作用,运用储层岩石学测试和镜下分析,研究了物源与储层发育的关系及分布,探讨了物源体系的控制因素。研究结果表明,四川盆地须家河组储层具有成分成熟度较低、物性差异性强、以中-细粒为... 详细信息

为明确四川盆地须家河组致密砂岩物源特征及控储作用,运用储层岩石学测试和镜下分析,研究了物源与储层发育的关系及分布,探讨了物源体系的控制因素。研究结果表明,四川盆地须家河组储层具有成分成熟度较低、物性差异性强、以中-细粒为主、主要为溶蚀孔隙和成岩效应存在两面性5个基本特征;物源控制了储层岩石类型的发育范围,平面展布存在差异性,其可溶矿物组分及含量亦有所不同,导致各地区孔隙发育及规模有所不同;西部龙门山和东北部大巴山是须家河组的主要供源区,前者表现为碳酸盐岩岩屑含量相对较高,后者表现为火山岩岩屑含量相对较高。不同时期造山活动强度的阶段性变化使得物源供应强度及类型也随之变化,储层岩石组分差异分化,进而控制储层垂向非均质性。研究成果可以为该区下一步的油气精细勘探提供借鉴。

关键词：四川盆地须家河组物源体系致密砂岩控储作用

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基于广义坐标形式的高斯最小拘束原理的多刚体系统动力学建模

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北京大学学报（自然科学版） 2016年第4期52卷 708-712页

作者：姚文莉青岛理工大学理学院青岛266520

通过采用动能及广义坐标显式的变分形式的高斯原理,明确了广义坐标形式的高斯拘束中各项的含义,以此建立以笛卡尔广义坐标表达的一般多刚体系统动力学问题的优化模型,并研究利用上述模型列写其他坐标体系下的高斯拘束的方法。采用该方... 详细信息

通过采用动能及广义坐标显式的变分形式的高斯原理,明确了广义坐标形式的高斯拘束中各项的含义,以此建立以笛卡尔广义坐标表达的一般多刚体系统动力学问题的优化模型,并研究利用上述模型列写其他坐标体系下的高斯拘束的方法。采用该方法可将多刚体系统的动力学问题变为求拘束极值的问题,并且只要给出广义笛卡尔坐标与其他广义坐标之间的雅可比关系式,便可方便地得到该坐标系统下的高斯拘束,建模过程简单且具有更强的通用性。采用广义笛卡尔坐标及拉格朗日坐标,对简单刚体的平面运动及定轴转动问题建立动力学优化模型,并验证了该方法的有效性。

关键词：高斯最小拘束原理笛卡尔广义坐标拉格朗日坐标体系多刚体系统动力学

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含有非理想完整约束的非完整系统的打击问题

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北京大学学报（自然科学版） 2010年第5期46卷 855-858页

作者：姚文莉青岛理工大学理学院青岛266520

研究了当非完整系统中含有非理想的完整约束时的打击问题的拉格朗日方法。针对一阶线性非完整系统,得到了含有多余广义坐标的非完整系统带乘子的拉格朗日方程,在此基础上推导了系统受到打击时,打击前后系统状态之间的关系及打击期间的... 详细信息

研究了当非完整系统中含有非理想的完整约束时的打击问题的拉格朗日方法。针对一阶线性非完整系统,得到了含有多余广义坐标的非完整系统带乘子的拉格朗日方程,在此基础上推导了系统受到打击时,打击前后系统状态之间的关系及打击期间的约束反力冲量。在算例中,详细描述了当打击冲量未知时该方法的实现过程。

关键词：非理想约束一阶线性非完整系统打击

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Sensor Failure Detection and Diagnosis via Polynomial Chaos Theory-PartⅡ:Digital Realization

Sensor Failure Detection and Diagnosis via Polynomial Chaos ...

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2013年中国智能自动化学术会议

作者： Weilin Li Xiaobin Zhang Huimin Li wenli yao School of Automation Northwestern Polytechnical University EE Department University of South Carolina

The reliability and performance of complex power systems with many sensors are largely dependent on the accuracy and reliability of the ***, it is very important for monitoring and diagnosis the sensor *** this paper, the digital realization of polynomial chaos theory(PCT) based sensor failure detection and diagnosis(SFDD) algorithm considering parameter uncertainties has been detailed.A digital signal processor(DSP),TMS320F2812,is adopted to implement the proposed SFDD *** hardware-in-the-loop testing and laboratory experimental testing have been done to verify the online practical application capability of the proposed algorithm.A three-stage synchronous generator with automatic voltage regulator(AVR) has been used as a case study. The control performance of AVR is guaranteed to be more reliable by the application of SFDD algorithm based on *** results show good consistency with the theory analysis.

关键词： Sensor failure detection and diagnosis Digital realization Polynomial chaos theory Synchronous generator Automatic voltage regulator

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