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Compressive damage constitutive model for brittle coal based on the compaction effect and linear energy dissipation law
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作者 Fengqiang Gong Lei Xu +2 位作者 Mingzhong Gao Yingjie Zhao Peilei Zhang 《International Journal of Coal Science & Technology》 2025年第3期225-247,共23页
The study of the mechanical property and damage state of coal materials under compression is a fundamental area of research in underground mining engineering.Drawing upon the compaction effect and linear energy dissip... The study of the mechanical property and damage state of coal materials under compression is a fundamental area of research in underground mining engineering.Drawing upon the compaction effect and linear energy dissipation(LED)law,a novel compressive damage constitutive model for brittle coal is proposed.Utilizing the energy-defined damage method for mate-rials,the LED law is innovatively introduced to accurately characterize the energy dissipation during the loading process,and a novel formula for characterizing the damage variable of brittle coal is proposed.On this basis,considering that the constitutive model based on the hypothesis of strain equivalence is incapable of accurately describing the compaction effect exhibited by coal material during the compression process,a correction coefficient is proposed and apply it in the novel damage constitutive model.The established conventional monotone loading and single-cyclic loading-unloading uniaxial compression damage constitutive models have been validated using experimental data from cylindrical and cuboid coal specimens.In addition,compared with the constitutive model obtained via the traditional energy calculation method based on the hypothesis that the unloading curve is a straight line,the constitutive model employing LED law can describe the stress-strain state of brittle coal more precisely.This approach introduces a new perspective and enhances the convenience for constructing the constitutive model based on energy theory. 展开更多
关键词 DAMAGE Constitutive model Compaction effect Brittle coal linear energy dissipation law
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Theoretical verification of the rationality of strain energy storage index as rockburst criterion based on linear energy storage law 被引量:12
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作者 Fengqiang Gong Song Luo +1 位作者 Quan Jiang Lei Xu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第6期1737-1746,共10页
The rationality of using strain energy storage index(Wet)for evaluating rockburst proneness was theoretically verified based on linear energy storage(LES)law in this study.The LES law is defined as the linear relation... The rationality of using strain energy storage index(Wet)for evaluating rockburst proneness was theoretically verified based on linear energy storage(LES)law in this study.The LES law is defined as the linear relationship between the elastic strain energy stored inside the solid material and the input strain energy during loading.It is used to determine the elastic strain energy and dissipated strain energy of rock specimens at various loading/unloading stress levels.The results showed that the Wetvalue obtained from experiments was close to the corresponding theoretical one from the LES law.Furthermore,with an increase in the loading/unloading stress level,the ratio of elastic strain energy to dissipated strain energy converged to the peak-strength strain energy storage index(Wp et).This index is stable and can better reflect the relative magnitudes of the stored energy and the dissipated energy of rocks at the whole pre-peak stage than the strain energy storage index.The peak-strength strain energy storage index can replace the conventional strain energy storage index as a new index for evaluating rockburst proneness. 展开更多
关键词 Rockburst criterion Strain energy storage index linear energy storage(LES)law Peak-strength strain energy storage index
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Impact angle control over composite guidance law based on feedback linearization and finite time control 被引量:8
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作者 ZHANG Xiaojian LIU Mingyong +1 位作者 LI Yang ZHANG Feihu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第5期1036-1045,共10页
The impact angle control over guidance(IACG) law against stationary targets is proposed by using feedback linearization control(FLC) and finite time control(FTC). First, this paper transforms the kinematics equation o... The impact angle control over guidance(IACG) law against stationary targets is proposed by using feedback linearization control(FLC) and finite time control(FTC). First, this paper transforms the kinematics equation of guidance systems into the feedbackable linearization model, in which the guidance law is obtained without considering the impact angle via FLC. For the purpose of the line of sight(LOS) angle and its rate converging to the desired values, the second-order LOS angle is considered as a double-integral system. Then, this paper utilizes FTC to design a controller which can guarantee the states of the double-integral system converging to the desired values. Numerical simulation illustrates the performance of the IACG, in contrast to the existing guidance law. 展开更多
关键词 guidance law impact angle feedback linearization finite time control global stabilization
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A general result on precise asymptotics for linear processes of positively associated sequences 被引量:10
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作者 TAN Xi-li YANG Xiao-yun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第2期190-196,共7页
Let {εt; t ∈ Z^+} be a strictly stationary sequence of associated random variables with mean zeros, let 0〈Eε1^2〈∞ and σ^2=Eε1^2+1∑j=2^∞ Eε1εj with 0〈σ^2〈∞.{aj;j∈Z^+} is a sequence of real numbers s... Let {εt; t ∈ Z^+} be a strictly stationary sequence of associated random variables with mean zeros, let 0〈Eε1^2〈∞ and σ^2=Eε1^2+1∑j=2^∞ Eε1εj with 0〈σ^2〈∞.{aj;j∈Z^+} is a sequence of real numbers satisfying ∑j=0^∞|aj|〈∞.Define a linear process Xt=∑j=0^∞ ajεt-j,t≥1,and Sn=∑t=1^n Xt,n≥1.Assume that E|ε1|^2+δ′〈 for some δ′〉0 and μ(n)=O(n^-ρ) for some ρ〉0.This paper achieves a general law of precise asymptotics for {Sn}. 展开更多
关键词 PA sequence linear process general law precise asymptotics.
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Critical dwell time of switched linear systems 被引量:2
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作者 Lijun ZHANG Chunwen LI 《控制理论与应用(英文版)》 EI 2006年第4期402-408,共7页
In this paper, we consider the relation between the switching dwell time and the stabilization of switched linear control systems. First of all, a concept of critical dwell time is given for switched linear systems wi... In this paper, we consider the relation between the switching dwell time and the stabilization of switched linear control systems. First of all, a concept of critical dwell time is given for switched linear systems without control inputs, and the critical dwell time is taken as an arbitrary given positive constant for a switched linear control systems with controllable switching models. Secondly, when a switched linear system has many stabilizable switching models, the problem of stabilization of the overall system is considered. An on-line feedback control is designed such that the overall system is asymptotically stabilizable under switching laws which depend only on those of uncontrollable subsystems of the switching models. Finally, when a switched system is partially controllable (While some switching models are probably unstabilizable), an on-line feedback control and a cyclic switching strategy are designed such that the overall system is asymptotically stabilizable if all switching models of this uncontrollable subsystems are asymptotically stable. In addition, algorithms for designing switching laws and controls are presented. 展开更多
关键词 Switched linear systems Switching law Critical dwell time STABILIZATION
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Interaction of elementary waves of scalar conservation laws with discontinuous flux function 被引量:3
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作者 王国栋 盛万成 《Journal of Shanghai University(English Edition)》 CAS 2006年第5期381-387,共7页
In this paper, the Riemann solutions for scalar conservation laws with discontinuous flux function were constructed. The interactions of elementary waves of the conservation laws were concerned, and the numerical simu... In this paper, the Riemann solutions for scalar conservation laws with discontinuous flux function were constructed. The interactions of elementary waves of the conservation laws were concerned, and the numerical simulations were given. 展开更多
关键词 discontinuous flux function scalar conservation laws linear discontinuity shock wave rarefaction wave.
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A New Optimal Guidance Law For Intercepting Maneuvering Objects
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作者 肖昌美 张福恩 程恭 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第3期58-62,共5页
In order to achieve a new minimum energy interception of an arbitrarily maneuvering vehicle a nonlinear modal is first approximated by a series of local linear models using an on-line linearizing method for some state... In order to achieve a new minimum energy interception of an arbitrarily maneuvering vehicle a nonlinear modal is first approximated by a series of local linear models using an on-line linearizing method for some state variables, and then from the derived local linear models a new optimal strategy is developed using the receding horizon concept and associated techniques. That evader maneuvering in a small scope can be dealt with by the correspoding local linear model, and its maneuverring in a large scope is handled by model switching among a series of local linear models. Simulation results show that tile system designed in this way can intercept a randomly maneuvering evader. 展开更多
关键词 Minimum-energy GUIDANCE law LOCAL linear model receding HORIZON control
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For Propulsion Applications It Is Possible to Utilize Both the Torque Output of the Rotor and the Reactional Torque Acting on the Stator of the Driving Electric Motor by Linearizing the Stator
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作者 Salah Abunaieb 《Energy and Power Engineering》 2021年第5期163-173,共11页
This paper presents a novel idea of utilizing the reactional torque of the conventional electric motor as a linear output for propulsion in addition to the conventional torque output of the rotor. The idea is demonstr... This paper presents a novel idea of utilizing the reactional torque of the conventional electric motor as a linear output for propulsion in addition to the conventional torque output of the rotor. The idea is demonstrated by a theoretical proposal of linearizing the stator of one of the most used motors </span><span style="font-family:Verdana;">in Electrical Vehicles and Hybrid Vehicles</span><span style="font-family:""><span style="font-family:Verdana;">. The proposed Linear Stator Motor is a </span><span style="font-family:Verdana;">simple modification without involving any functional change of the conventional motor. Though theoretical, the indicated possible input </span><span style="font-family:Verdana;">energy saving of more than 75% as compared to the conventional motor is no surprise, as by linearizing the stator, an almost equal linear propulsion output is added to the conventional rotor output. In addition to this remarkable saving in input energy, the proposed Linear Stator Motor that suits all type</span></span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> of vehicle</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;">, can maintain propulsion without the need for a mechanical transmission system. Also, in </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">case of watercraft and aircraft vehicles, no external mechanical propulsion drive system is required. It is just an internal force that can push the vehicle forward, backward</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> or laterally, while the conventional rotor output can be utilized for energy recovery by driving a DC generator. 展开更多
关键词 BLDC Motor Electrical Vehicle Hall Effect linearIZATION Newton’s Third law of Motion PROPULSION ROTOR STATOR
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An Efficient Guidance Law for Intercepting Maneuvering Evader in Three-Dimensions
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作者 肖昌美 张福恩 程恭 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第4期34-38,共5页
Considering the nonlinear model between a realistic missile and an aircraft in three-dimensions, one minimun energy guidance law is obtained. By employing the linearizing method, an efficient and robust guidance law f... Considering the nonlinear model between a realistic missile and an aircraft in three-dimensions, one minimun energy guidance law is obtained. By employing the linearizing method, an efficient and robust guidance law for intercepting randomly maneuvering evader is derived. A new approach to pursuit-evasion problem in two-dimensions and three-dimensions is provided, which can deal with the randomly maneuvering evader in time. Numerical simulations denote that the system designed by this method can cut down the miss distance remarkably. 展开更多
关键词 Minimum ENERGY GUIDANCE law ON-LINE linearizing receding HORIZON control
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CONSTITUTIVE RELATION OF UNSATURATED SOIL BY USE OF THE MIXTURE THEORY (Ⅱ)—LINEAR CONSTITUTIVE EQUATIONS AND FIELD EQUATIONS
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作者 黄义 张引科 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第2期138-152,共15页
The linear constitutive equations and field equations of unsaturated soils were obtained through linearizing the nonlinear equations given in the first part of this work. The linear equations were expressed in the for... The linear constitutive equations and field equations of unsaturated soils were obtained through linearizing the nonlinear equations given in the first part of this work. The linear equations were expressed in the forms similar to Biot's equations for saturated porous media. The Darcy's laws of unsaturated soil were proved. It is shown that Biot's equations of saturated porous media are the simplification of the theory. All these illustrate that constructing constitutive relation of unsaturated soil on the base of mixture theory is rational. 展开更多
关键词 mixture theory unsaturated soil linear constitutive equation linear field equation Darcy's law Biot's equations
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Strong Stability of Linear Forms in φ-Mixing Random Variables 被引量:2
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作者 GAN Shixin 《Wuhan University Journal of Natural Sciences》 CAS 2009年第1期6-10,共5页
In this paper some new results of strong stability of linear forms in φ-mixing random variables are given. It is mainly proved that for a sequence of φ-mixing random variables {xn,n≥1} and two sequences of positive... In this paper some new results of strong stability of linear forms in φ-mixing random variables are given. It is mainly proved that for a sequence of φ-mixing random variables {xn,n≥1} and two sequences of positive numbers {an,n≥1} and {bn,n≥1} there exist d dn∈R,n = 1,2,..., such that bn^-1∑i=1^naixi-dn→0 a.s.under some suitable conditions. The results extend and improve the corresponding theorems for independent identically distributed random variables. 展开更多
关键词 strong stability linear form φ-mixing random variable sequence strong law of large numbers
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ESTIMATION FOR THE AYMPTOTIC VARIANCE OF PARAMETRIC ESTIMATES IN PARTIAL LINEAR MODEL WITH CENSORED DATA 被引量:2
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作者 秦更生 蔡雷 《Acta Mathematica Scientia》 SCIE CSCD 1996年第2期192-208,共17页
Consider tile partial linear model Y=Xβ+ g(T) + e. Wilers Y is at risk of being censored from the right, g is an unknown smoothing function on [0,1], β is a 1-dimensional parameter to be estimated and e is an unobse... Consider tile partial linear model Y=Xβ+ g(T) + e. Wilers Y is at risk of being censored from the right, g is an unknown smoothing function on [0,1], β is a 1-dimensional parameter to be estimated and e is an unobserved error. In Ref[1,2], it wes proved that the estimator for the asymptotic variance of βn(βn) is consistent. In this paper, we establish the limit distribution and the law of the iterated logarithm for,En, and obtain the convergest rates for En and the strong uniform convergent rates for gn(gn). 展开更多
关键词 Partial linear model Censored data Kernel method Asymptotic normality Thc law of the iterated logarithm.
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The Equilibrium of Fractional Derivative and Second Derivative: The Mechanics of a Power-Law Visco-Elastic Solid
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作者 Franz Konstantin Fuss 《Applied Mathematics》 2016年第16期1903-1918,共17页
This paper investigates the equilibrium of fractional derivative and 2nd derivative, which occurs if the original function is damped (damping of a power-law viscoelastic solid with viscosities η of 0 ≤ η ≤ 1), whe... This paper investigates the equilibrium of fractional derivative and 2nd derivative, which occurs if the original function is damped (damping of a power-law viscoelastic solid with viscosities η of 0 ≤ η ≤ 1), where the fractional derivative corresponds to a force applied to the solid (e.g. an impact force), and the second derivative corresponds to acceleration of the solid’s centre of mass, and therefore to the inertial force. Consequently, the equilibrium satisfies the principle of the force equilibrium. Further-more, the paper provides a new definition of under- and overdamping that is not exclusively disjunctive, i.e. not either under- or over-damped as in a linear Voigt model, but rather exhibits damping phases co-existing consecutively as time progresses, separated not by critical damping, but rather by a transition phase. The three damping phases of a power-law viscoelastic solid—underdamping, transition and overdamping—are characterized by: underdamping—centre of mass oscillation about zero line;transition—centre of mass reciprocation without crossing the zero line;overdamping—power decay. The innovation of this new definition is critical for designing non-linear visco-elastic power-law dampers and fine-tuning the ratio of under- and overdamping, considering that three phases—underdamping, transition, and overdamping—co-exist consecutively if 0 < η < 0.401;two phases—transition and overdamping—co-exist consecutively if 0.401 < η < 0.578;and one phase— overdamping—exists exclusively if 0.578 < η < 1. 展开更多
关键词 Fractional Derivative Non-linear Visco-Elasticity Power law Mittag-Leffler Function Underdamping Overdamping Innovative Design of Material Damping
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Iterated Logarithm Laws on GLM Randomly Censored with Random Regressors and Incomplete Information
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作者 Qiang Zhu Zhihong Xiao +1 位作者 Guanglian Qin Fang Ying 《Applied Mathematics》 2011年第3期363-368,共6页
In this paper, we define the generalized linear models (GLM) based on the observed data with incomplete information and random censorship under the case that the regressors are stochastic. Under the given conditions, ... In this paper, we define the generalized linear models (GLM) based on the observed data with incomplete information and random censorship under the case that the regressors are stochastic. Under the given conditions, we obtain a law of iterated logarithm and a Chung type law of iterated logarithm for the maximum likelihood estimator (MLE) in the present model. 展开更多
关键词 Generalized linear Model INCOMPLETE Information Stochastic Regressor ITERATED LOGARITHM lawS
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幂律流体在不同接触率裂隙介质中的渗流规律
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作者 赵茉莉 徐恺 +2 位作者 王少伟 李树忱 李柄霖 《煤炭学报》 北大核心 2025年第S2期994-1006,共13页
铀矿是国家重要的战略资源,而砂岩型铀矿赋存于煤层之间的铀矿含水层中,当进行煤铀协调开采时,在上下部煤层开采的应力扰动下,常发生砂岩原有裂隙的接触变化。考虑到铀矿地浸开采中必然受非牛顿流体溶液的影响,为探究接触扰动下砂岩裂... 铀矿是国家重要的战略资源,而砂岩型铀矿赋存于煤层之间的铀矿含水层中,当进行煤铀协调开采时,在上下部煤层开采的应力扰动下,常发生砂岩原有裂隙的接触变化。考虑到铀矿地浸开采中必然受非牛顿流体溶液的影响,为探究接触扰动下砂岩裂隙的非牛顿流体渗流规律,依据巴西劈裂形成的真实砂岩表面,进行数字化重构。针对幂律流体在不同接触率裂隙模型中的流动进行数值模拟,探究了接触率与幂律流体特性在压力场、速度场的耦合效应,揭示了接触扰动下槽流、涡流的发展规律,提出针对不同幂律流体,相同流向横截面积的大小对截面压力、流速的变化趋势。结果表明:接触率的增大会增强流动的非线性。在接触区附近出现明显的压力分割线,更小的幂律指数与更大的入口速度表现为更强的压力阻隔效应。接触区之间的槽道为流体加速区域,小黏度流体对槽道的加速效果更加敏感,同时易在回流区产生涡流且涡流面积随着速度的增大而增大。裂隙的横截面积与裂隙的渗流速度呈相反的关系,而对于压力分布,压力与横截面积并非单调对应而是沿流向可能存在上升区域。压力曲线的变化和速度曲线的变化趋势相反,这种对应关系随着接触率的减小而增大,且压力曲线的变化稍滞后于速度曲线的变化。此外,不同幂律指数、入口速度的幂律流体在不同接触条件下的流动状态差异较为明显,证实幂律流体的流动对于接触面积、幂律指数以及入口流速具有一定的敏感性。 展开更多
关键词 幂律流体 非线性渗流 裂隙介质 接触率 槽流
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The Effects of Rotation and Salt Concentration On Thermal Convection In a Linear Magneto-Fluid Layer Overlying a Porous Layer
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作者 Maram S. Al-Qurashi Abdul-Fattah K. Bukhari 《Journal of Electromagnetic Analysis and Applications》 2012年第9期367-378,共12页
A linear stability analysis is applied to a system consisting of a linear magneto-fluid layer overlying a porous layer affected by rotation and salt concentration on both layers. The flow in the fluid layer is governe... A linear stability analysis is applied to a system consisting of a linear magneto-fluid layer overlying a porous layer affected by rotation and salt concentration on both layers. The flow in the fluid layer is governed by Navier-Stokes’s equations and while governed by Darcy-Brinkman’s law in the porous medium. Numerical solutions are obtained using Legendre polynomials. These solutions are studied through two modes of instability: stationary instability and overstability when the heat and the salt concentration are effected from above and below. 展开更多
关键词 NAVIER-STOKES Equation Darcy-Brinkman law LEGENDRE POLYNOMIALS Salt Concentration Vertical linear Magnetic Field
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A Simple Theory of Asymmetric Linear Elasticity
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作者 Zehua Qiu 《World Journal of Mechanics》 2020年第10期166-185,共20页
Rotation is antisymmetric and therefore is not a coherent element of the classical elastic theory, which is characterized by symmetry. A new theory of linear elasticity is developed from the concept of asymmetric stra... Rotation is antisymmetric and therefore is not a coherent element of the classical elastic theory, which is characterized by symmetry. A new theory of linear elasticity is developed from the concept of asymmetric strain, which is defined as the transpose of the deformation gradient tensor to involve rotation as well as symmetric strain. The new theory basically differs from the prevailing micropolar theory or couple stress theory in that it maintains the same basis as the classical theory of linear elasticity and does not need extra concepts, such as “microrotation” and “couple stresses”. The constitutive relation of the new theory, the three-parameter Hooke’s law, comes from the theorem about isotropic asymmetric linear elastic materials. Concise differential equations of translational motion are derived consequently giving the same velocity formula for P-wave and a different one for S-wave. Differential equations of rotational motion are derived with the introduction of spin, which has an intrinsic connection with rotation. According to the new theory, S-wave essentially has rotation as large as deviatoric strain and should be referred to as “shear wave” in the context of asymmetric strain. There are nine partial differential equations for the deformation harmony condition in the new theory;these are given with the first spatial differentiations of asymmetric strain. Formulas for rotation energy, in addition to those for (symmetric) strain energy, are derived to form a complete set of formulas for the total mechanical energy. 展开更多
关键词 linear Elasticity Asymmetric linear Elasticity Asymmetric Strain Asymmetric Stress Three-Parameter Hooke’s law
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雷达目标探测的平方根和四次方根检波律研究
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作者 颜志升 沈石坚 邢雷 《现代雷达》 北大核心 2025年第5期92-99,共8页
为了解决在雷达目标探测中干扰目标带来的遮蔽问题,文中提出了平方根检波律和四次方根检波律搭配单元平均恒虚警率检测器使用,雷达检测性能相对不易受到干扰目标的负面影响。与经典的线性检波律和平方检波律相比较,平方根检波律和四次... 为了解决在雷达目标探测中干扰目标带来的遮蔽问题,文中提出了平方根检波律和四次方根检波律搭配单元平均恒虚警率检测器使用,雷达检测性能相对不易受到干扰目标的负面影响。与经典的线性检波律和平方检波律相比较,平方根检波律和四次方根检波律不会造成附加的检测损失;与通常用来抑制干扰目标的遮蔽效应的对数检波律和排序统计恒虚警率检测相比较,平方根检波律和四次方根检波律具有更高的实现效率。通过真实雷达数据进行验证,当孤立的干扰目标的回波信号比背景噪声高出40 dB并且用来估计背景噪声功率的样本的个数等于32时,四次方根检波律对干扰目标的抑制能力比线性检波律改进10 dB以上。 展开更多
关键词 单元平均恒虚警率 线性检波律 平方检波律 平方根检波律 四次方根检波律
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基于线性超螺旋滑模观测器的永磁同步电机转速估计研究
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作者 申江卫 高尔普 +2 位作者 夏雪磊 陈峥 沈世全 《昆明理工大学学报(自然科学版)》 北大核心 2025年第6期89-100,共12页
为解决传统永磁同步电机(PMSM)无传感器控制系统中,滑模控制方法普遍存在的收敛速度慢、抖振现象严重等问题,本文提出一种基于线性超螺旋滑模观测器(Linear Super-Twisting Sliding Mode Observer, LST-SMO)与新型趋近律速度控制器的无... 为解决传统永磁同步电机(PMSM)无传感器控制系统中,滑模控制方法普遍存在的收敛速度慢、抖振现象严重等问题,本文提出一种基于线性超螺旋滑模观测器(Linear Super-Twisting Sliding Mode Observer, LST-SMO)与新型趋近律速度控制器的无传感器控制策略.首先,在传统超螺旋滑模观测器(Super-Twisting Sliding Mode Observer, ST-SMO)基础上引入线性校正项,设计线性超螺旋滑模观测器;该观测器估计反电动势时输出信号几乎不含高频干扰分量,可直接避免低通滤波器的使用,进而有效提升转子位置与速度的估计精度.其次,设计新型趋近律速度控制器,该控制器能够根据系统状态自动调节滑模增益系数,在显著抑制系统抖振的同时加快动态响应速度.通过构造Lyapunov函数,严格证明了所提控制算法的稳定性.最后,在搭建的实验平台上,以一台750 W永磁同步电机为控制对象开展验证实验.仿真与实验结果表明:线性超螺旋滑模观测器将转子位置估计精度提升48%,转速误差从14 r/min降低至1.4 r/min,充分验证了所提方法的有效性与可行性. 展开更多
关键词 永磁同步电机 线性超螺旋 滑模观测器 趋近律 转速控制
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基于滑模控制律的机翼极限环主动抑制
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作者 王诗其 张征 +2 位作者 宋晨 杨超 郑焱午 《北京航空航天大学学报》 北大核心 2025年第6期2033-2040,共8页
间隙非线性机翼系统在一定速度范围内会发生极限环振荡,传统线性控制律对极限环抑制效果通常不显著且鲁棒性不足,因此,需设计相应的非线性控制律来提高系统的控制效果及鲁棒性。通过对间隙非线性二元翼段气动弹性系统进行线性二次调节(L... 间隙非线性机翼系统在一定速度范围内会发生极限环振荡,传统线性控制律对极限环抑制效果通常不显著且鲁棒性不足,因此,需设计相应的非线性控制律来提高系统的控制效果及鲁棒性。通过对间隙非线性二元翼段气动弹性系统进行线性二次调节(LQR)控制律设计,结果显示:极限环速度范围由11.4~16.9 m/s优化至12.9~19.2 m/s。同时,对间隙非线性二元翼段气动弹性系统进行滑模控制律(SMC)设计,结果显示:极限环速度范围由11.4~16.9 m/s优化至29.4~39.3 m/s。算例结果表明:针对间隙非线性系统,所设计SMC效果优于LQR控制律。 展开更多
关键词 间隙非线性 极限环振荡 控制律 线性二次调节 滑模控制律
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