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Moments of inertia of triaxial nuclei in covariant density functional theory
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作者 Yu-Meng Wang Qi-Bo Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期197-207,共11页
The covariant density functional theory(CDFT)and five-dimensional collective Hamiltonian(5DCH)are used to analyze the experimental deformation parameters and moments of inertia(MoIs)of 12 triaxial nuclei as extracted ... The covariant density functional theory(CDFT)and five-dimensional collective Hamiltonian(5DCH)are used to analyze the experimental deformation parameters and moments of inertia(MoIs)of 12 triaxial nuclei as extracted by Allmond and Wood[J.M.Allmond and J.L.Wood,Phys.Lett.B 767,226(2017)].We find that the CDFT MoIs are generally smaller than the experimental values but exhibit qualitative consistency with the irrotational flow and experimental data for the relative MoIs,indicating that the intermediate axis exhibites the largest MoI.Additionally,it is found that the pairing interaction collapse could result in nuclei behaving as a rigid-body flow,as exhibited in the^(186-192)Os case.Furthermore,by incorporating enhanced CDFT MoIs(factor of f≈1.55)into the 5DCH,the experimental low-lying energy spectra and deformation parameters are reproduced successfully.Compared with both CDFT and the triaxial rotor model,the 5DCH demonstrates superior agreement with the experimental deformation parameters and low-lying energy spectra,respectively,emphasizing the importance of considering shape fluctuations. 展开更多
关键词 moment of inertia Trixial nucleus Covariant density functional theory Five-dimensional collective Hamiltonian Low-lying energy spectrum
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GENERALIZED COUNTING FUNCTIONS AND COMPOSITION OPERATORS ON WEIGHTED BERGMAN SPACES OF DIRICHLET SERIES
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作者 Min HE Maofa WANG Jiale CHEN 《Acta Mathematica Scientia》 2025年第2期291-309,共19页
In this paper,we study composition operators on weighted Bergman spaces of Dirichlet series.We first establish some Littlewood-type inequalities for generalized mean counting functions.Then we give sufficient conditio... In this paper,we study composition operators on weighted Bergman spaces of Dirichlet series.We first establish some Littlewood-type inequalities for generalized mean counting functions.Then we give sufficient conditions for a composition operator with zero characteristic to be bounded or compact on weighted Bergman spaces of Dirichlet series.The corresponding sufficient condition for compactness in the case of positive characteristics is also obtained. 展开更多
关键词 generalized counting function Dirichlet series composition operator weighted Bergman space
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A Basis Function Generation Based Digital Predistortion Concurrent Neural Network Model for RF Power Amplifiers
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作者 SHAO Jianfeng HONG Xi +2 位作者 WANG Wenjie LIN Zeyu LI Yunhua 《ZTE Communications》 2025年第1期71-77,共7页
This paper proposes a concurrent neural network model to mitigate non-linear distortion in power amplifiers using a basis function generation approach.The model is designed using polynomial expansion and comprises a f... This paper proposes a concurrent neural network model to mitigate non-linear distortion in power amplifiers using a basis function generation approach.The model is designed using polynomial expansion and comprises a feedforward neural network(FNN)and a convolutional neural network(CNN).The proposed model takes the basic elements that form the bases as input,defined by the generalized memory polynomial(GMP)and dynamic deviation reduction(DDR)models.The FNN generates the basis function and its output represents the basis values,while the CNN generates weights for the corresponding bases.Through the concurrent training of FNN and CNN,the hidden layer coefficients are updated,and the complex multiplication of their outputs yields the trained in-phase/quadrature(I/Q)signals.The proposed model was trained and tested using 300 MHz and 400 MHz broadband data in an orthogonal frequency division multiplexing(OFDM)communication system.The results show that the model achieves an adjacent channel power ratio(ACPR)of less than-48 d B within a 100 MHz integral bandwidth for both the training and test datasets. 展开更多
关键词 basis function generation digital predistortion generalized memory polynomial dynamic deviation reduction neural network
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Analysis of a Cavity Used for Medical Purposes with the Dyadic Green's Functions and the Moment method
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作者 薛正辉 刘永善 +1 位作者 李德生 王堃 《Journal of Beijing Institute of Technology》 EI CAS 1996年第1期19-26,共8页
The structure of a microwave radiator used for medical purposes is described. The dyadic Green's function and the method are used to analyze this Kind of multimode rectangular medium-filled cavity. The distributio... The structure of a microwave radiator used for medical purposes is described. The dyadic Green's function and the method are used to analyze this Kind of multimode rectangular medium-filled cavity. The distribution of electromagnetic field intensity and the power density,as well as the temperature effect in the biological sample load are obtained.OPtimization of the size of cavity and the position of the input aperture have been performed with the computer to optimize the uniformity or microwave effect and the input VSWR.Necessary experiments were performed to compare the data obtained with theoretical analysis. 展开更多
关键词 microwave therapy apparatus moment problems dyadic Green's function
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Generating function of product of bivariate Hermite polynomials and their applications in studying quantum optical states 被引量:1
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作者 范洪义 张鹏飞 王震 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第5期204-209,共6页
By virtue of the operator-Hermite-polynomial method, we derive some new generating function formulas of the product of two bivariate Hermite polynomials. Their applications in studying quantum optical states are prese... By virtue of the operator-Hermite-polynomial method, we derive some new generating function formulas of the product of two bivariate Hermite polynomials. Their applications in studying quantum optical states are presented. 展开更多
关键词 operator-Hermite-polynomials (OHP) method generating function product of bivariate Hermite polynomials
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Some new generating function formulae of the two-variable Hermite polynomials and their application in quantum optics 被引量:1
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作者 展德会 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期30-33,共4页
We derive some new generating function formulae of the two-variable Hermite polynomials, such as ∞∑n=0tm/m!Hn,2m(x),∞∑n=0sntm/n!m!H2n,2m(x,y),and ∞∑n=0sntm/n!m!H2n+l,2m+k(x,y).We employ the operator Herm... We derive some new generating function formulae of the two-variable Hermite polynomials, such as ∞∑n=0tm/m!Hn,2m(x),∞∑n=0sntm/n!m!H2n,2m(x,y),and ∞∑n=0sntm/n!m!H2n+l,2m+k(x,y).We employ the operator Hermite polynomial method and the technique of integration within an ordered product of operators to solve these problems, which will be useful in constructing new optical field states. 展开更多
关键词 generating function two-variable Hermite polynomials Hermite polynomial method technique of integral within an ordered product of operators
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New generating function formulae of even- and odd-Hermite polynomials obtained and applied in the context of quantum optics 被引量:1
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作者 范洪义 展德会 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第6期18-22,共5页
By combining the operator Hermite polynomial method and the technique of integration within an ordered product of operators, for the first time we derive the generating function of even- and odd-Hermite polynomials wh... By combining the operator Hermite polynomial method and the technique of integration within an ordered product of operators, for the first time we derive the generating function of even- and odd-Hermite polynomials which will be useful in constructing new optical field states. We then show that the squeezed state and photon-added squeezed state can be expressed by even- and odd-Hermite polynomials. 展开更多
关键词 generating function even- and odd-Hermite polynomials Hermite polynomial method techniqueof integral within an ordered product of operators
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Quantum fields presentation and generating functions of symplectic Schur functions and symplectic universal characters
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作者 Denghui Li Fei Wang Zhaowen Yan 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第8期197-206,共10页
This paper is concerned with construction of quantum fields presentation and generating functions of symplectic Schur functions and symplectic universal characters.The boson-fermion correspondence for these symmetric ... This paper is concerned with construction of quantum fields presentation and generating functions of symplectic Schur functions and symplectic universal characters.The boson-fermion correspondence for these symmetric functions have been presented.In virtue of quantum fields,we derive a series of infinite order nonlinear integrable equations,namely,universal character hierarchy,symplectic KP hierarchy and symplectic universal character hierarchy,respectively.In addition,the solutions of these integrable systems have been discussed. 展开更多
关键词 quantum fields generating functions integrable systems symmetric functions boson–fermion correspondence
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Ostrowski’s Type Inequalities for Generalized(h,m)−Preinvex Functions with Its Applications
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作者 LI Ran LIAN Tie-yan 《Chinese Quarterly Journal of Mathematics》 2024年第3期270-287,共18页
A new concept generalized(h,m)−preinvex function on Yang’s fractal sets is proposed.Some Ostrowski’s type inequalities with two parameters for generalized(h,m)−preinvex function are established,where three local fra... A new concept generalized(h,m)−preinvex function on Yang’s fractal sets is proposed.Some Ostrowski’s type inequalities with two parameters for generalized(h,m)−preinvex function are established,where three local fractional inequalities involving generalized midpoint type,trapezoid type and Simpson type are derived as consequences.Furthermore,as some applications,special means inequalities and numerical quadratures for local fractional integrals are discussed. 展开更多
关键词 Generalized(h m)−preinvex function Hermite−Hadamard inequality Ostrowski inequality Simpson inequality
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基于气象数据外推法和显著性分析的光伏自适应功率预测模型
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作者 王丽婕 张青山 +3 位作者 郝颖 周颖 邱敏 孙冲 《太阳能学报》 北大核心 2025年第2期317-325,共9页
分布式光伏电站装机容量较小,一般不进行实时功率统计,难以直接建立功率预测模型。针对分布式光伏电站间光伏组件安装型号和安装方式多样性的问题,基于气象数据外推法和显著性分析提出一种自适应功率预测模型。首先,利用显著性分析筛选... 分布式光伏电站装机容量较小,一般不进行实时功率统计,难以直接建立功率预测模型。针对分布式光伏电站间光伏组件安装型号和安装方式多样性的问题,基于气象数据外推法和显著性分析提出一种自适应功率预测模型。首先,利用显著性分析筛选光伏组件标称参数和气象数据外推法特征参数之间的相关性,确定与特征参数显著相关的标称参数集合;然后,建立最小二乘支持向量机模型,拟合标称参数集合和特征参数之间的自适应函数关系;最后,建立自适应功率预测模型,基于光伏组件安装方式将环境温度和辐照度转换为板面温度和辐照度,基于自适应函数选择适合当前光伏组件型号的特征参数,根据气象数据外推法得到预测功率。利用光伏电站实际数据进行验证,结果显示,自适应功率预测模型能够为不同型号的光伏组件选择合适的特征参数,通用性更强,相比于目前流行的简化功率预测模型,多云天气下的预测精度提升约2.34%。 展开更多
关键词 光伏发电 功率预测 外推法 显著性分析 自适应函数
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孤岛模式下基于VSG的光储发电系统多机并联运行策略
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作者 张萍 李扬 《全球能源互联网》 北大核心 2025年第1期98-109,共12页
随着光伏发电装机容量的大幅增加,电力系统呈现“低惯性、低阻尼”特性,虚拟同步发电机(virtual synchronous generators,VSG)技术可以提高系统稳定性和供电可靠性。针对孤岛模式下光储-VSG并联系统由于线路阻抗差异和负载投切等原因导... 随着光伏发电装机容量的大幅增加,电力系统呈现“低惯性、低阻尼”特性,虚拟同步发电机(virtual synchronous generators,VSG)技术可以提高系统稳定性和供电可靠性。针对孤岛模式下光储-VSG并联系统由于线路阻抗差异和负载投切等原因导致的系统环流及功率分配不均问题,提出一种协同自适应控制策略。首先,通过系统无功功率偏差动态调整虚拟阻抗值,实现无功功率的精确分配,从而抑制系统稳态环流。其次,为提升系统动态特性和抑制负载投切过程中系统的振荡,建立双输入三输出径向基函数(radial basis function,RBF)神经网络对系统关键参数进行优化。最后,建立3台光储-VSG并联模型,设定不同容量比进行仿真分析,验证了所提控制策略能更好地抑制系统环流,保证系统稳定运行。 展开更多
关键词 光储发电系统 虚拟同步发电机 动态虚拟阻抗 RBF神经网络 环流抑制
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新时期我国通航文化发展策略研究
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作者 杨芳 《成都航空职业技术学院学报》 2025年第1期113-116,共4页
通航文化是通航产业的灵魂,对通航的发展具有现实价值和意义。国内通航文化发展起步较晚,与国外发达国家还存在较大差距。对比国内外通航产业和文化发展现状,采用文献统计分析法,梳理国内通航文化发展现状;通过分析国外通航发展历程特... 通航文化是通航产业的灵魂,对通航的发展具有现实价值和意义。国内通航文化发展起步较晚,与国外发达国家还存在较大差距。对比国内外通航产业和文化发展现状,采用文献统计分析法,梳理国内通航文化发展现状;通过分析国外通航发展历程特点及国内信息传播的基础优势,提出政府扶持、制度改革、产业集群式发展、科技创新、体系创建的通航文化建设策略和充分利用群众基础、社区职能、新媒体发展,大力推广通航文化的传播策略。 展开更多
关键词 通用航空 社区职能 产业集群 新媒体
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基于单张量辐射场的数字服装重照明方法
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作者 陈鑫磊 郑军红 +1 位作者 金耀 何利力 《丝绸》 CAS 北大核心 2025年第1期85-93,共9页
针对现有基于三维表面重建的图像重照明方法存在纹理噪点、重照明质量不足及特征空间利用率低等问题,文章提出一种基于单张量辐射场的数字服装重照明方法。该方法首先利用球面高斯函数和多层感知机,分别模拟环境直射光和服装表面间的间... 针对现有基于三维表面重建的图像重照明方法存在纹理噪点、重照明质量不足及特征空间利用率低等问题,文章提出一种基于单张量辐射场的数字服装重照明方法。该方法首先利用球面高斯函数和多层感知机,分别模拟环境直射光和服装表面间的间接反射光,以构建一个精准的入射光场;接着通过引入梯度引导平滑策略,优化从特征空间中提取双向反射分布函数模型参数的过程。最后,利用简化的反射率方程,结合入射光场、双向反射分布模型及特征空间,成功地渲染出高质量的服装重照明图像。实验结果表明,该方法有效地减少了服装纹理噪点,显著降低了服装重照明的失真现象。相较于先进方法,该方法在生成服装新视角图像方面,各项评估指标的平均提升约9.922%;在服装重照明结果方面,各项评估指标的平均提升约4.549%。 展开更多
关键词 单张量辐射场 特征空间 服装重照明 3D维重建 图像生成 双向反射分布函数
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Generalized Numerical Radius of Real Quaternion Matrices with Symmetric Function
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作者 夏铁成 张鸿庆 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期34-38,共5页
In the paper the generalized numerical radiuses of real quaternion matrices with symmetric function are defined and theirs inequalities are given.
关键词 numerical radius generalized numerical radius symmetric function
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The Similarity Transformation of Regularizing Functionals and Simularity Property of Their Fourier Transformations
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作者 祝同江 《Journal of Beijing Institute of Technology》 EI CAS 1995年第2期105+99-105,共8页
Let and denote respectively the functionswhere λ≥1, The author discusses the similarity transformation of the regularizing functionals of these functions and the similar property of their Fourier transformation.
关键词 Fourier transform generalized functions/similarity transformation regularizing functionals
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The Fourier Transform of a Sort of Generalized Function
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作者 祝同江 《Journal of Beijing Institute of Technology》 EI CAS 1996年第2期106+101-106,共7页
The Fourier transforms of functions X ln e are given. where λ is a complex constant (λ≠-1,-2. …), a is a complex number. m=0. 1. 2,…,and
关键词 Fourier transform generalized function analytic exextension
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考虑疫苗有效性的传染病渗流模型
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作者 高杰 李毅红 罗晓峰 《中北大学学报(自然科学版)》 2025年第2期254-260,共7页
疫苗接种是当前公认的防控传染病传播时成本效益最高的公共卫生干预措施之一,对预防和控制传染病的暴发至关重要。在针对复杂网络中带有疫苗接种的传染病传播的点-边渗流模型基础上,根据存在的实际因素,考虑了疫苗有效性对人群中传染病... 疫苗接种是当前公认的防控传染病传播时成本效益最高的公共卫生干预措施之一,对预防和控制传染病的暴发至关重要。在针对复杂网络中带有疫苗接种的传染病传播的点-边渗流模型基础上,根据存在的实际因素,考虑了疫苗有效性对人群中传染病传播的影响。分析并计算出传染病传播的流行阈值以及平均暴发规模的精确理论结果,并通过数值模拟研究了度分布分别为泊松、指数、幂律分布的情况下,疫苗有效性对传染病在人群中传播的流行阈值以及传播最终规模的影响。研究结果表明,提高疫苗有效性、合理均匀化接触网络能有效防止传染病的暴发。 展开更多
关键词 生成函数 流行阈值 最终暴发规模 点-边渗流模型 疫苗有效性
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Multiparameter generalized universal characters and multiparameter generalized B-type universal characters
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作者 Jingfan Wang Zhaowen Yan 《Chinese Physics B》 2025年第1期215-226,共12页
We construct the quantum fields presentation of the generalized universal character and the generalized B-type universal character,and by acting the quantum fields presentations to the constant 1,the generating functi... We construct the quantum fields presentation of the generalized universal character and the generalized B-type universal character,and by acting the quantum fields presentations to the constant 1,the generating functions are derived.Furthermore,we introduce two integrable systems known as the generalized UC(GUC)hierarchy and the generalized Btype UC(GBUC)hierarchy satisfied by the generalized universal character and the generalized B-type universal character,respectively.Based on infinite sequences of complex numbers,we further establish the multiparameter generalized universal character and the multiparameter generalized B-type universal character,which have been proved to be solutions of the GUC hierarchy and the GBUC hierarchy,respectively. 展开更多
关键词 symmetric functions quantum fields generating functions multiparameter generalized universal characters
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A coherent generator group identification algorithm under extreme conditions
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作者 Yizhe Zhu Yulin Chen +3 位作者 Li Li Donglian Qi Jinhua Huang Xudong Song 《Global Energy Interconnection》 2025年第1期92-105,共14页
With the rapid development of large-scale regional interconnected power grids,the risk of cascading failures under extreme condi-tions,such as natural disasters and military strikes,has increased significantly.To enha... With the rapid development of large-scale regional interconnected power grids,the risk of cascading failures under extreme condi-tions,such as natural disasters and military strikes,has increased significantly.To enhance the response capability of power systems to extreme events,this study focuses on a method for generator coherency detection.To overcome the shortcomings of the traditional slow coherency method,this paper introduces a novel coherent group identification algorithm based on the theory of nonlinear dynam-ical systems.By analyzing the changing trend of the Euclidean norm of the state variable derivatives in the reduced system,the algorithm can accurately identify the magnitude of the disturbances.Based on the slow coherency methods,the algorithm can correctly recognize coherent generator groups by analyzing system characteristics under varying disturbance magnitudes.This improvement enhances the applicability and accuracy of the coherency detection algorithm under extreme conditions,providing support for emergency control and protection in the power system.Simulations and comparison analyses on IEEE 39-bus system are conducted to validate the accuracy and superiority of the proposed coherent generator group identification method under extreme conditions. 展开更多
关键词 Generator grouping Slow coherency method Nonlinear dynamical system BCU method Energy function
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基于滑模变结构的双馈风力发电机矢量控制
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作者 朱耀明 张兰红 陈露露 《南方能源建设》 2025年第1期160-167,共8页
[目的]电流环是双馈风力发电机并网过程中的重要控制环节。针对传统PI控制时双馈风力发电系统在参数摄动时动态性能不佳以及传统趋近律滑模控制存在抖振问题,对滑模变结构进行了研究和设计。[方法]基于滑模变结构的双馈风力发电机矢量... [目的]电流环是双馈风力发电机并网过程中的重要控制环节。针对传统PI控制时双馈风力发电系统在参数摄动时动态性能不佳以及传统趋近律滑模控制存在抖振问题,对滑模变结构进行了研究和设计。[方法]基于滑模变结构的双馈风力发电机矢量控制研究方法主要聚焦于利用滑模变结构控制的优点,如响应速度快、对参数变化和扰动不敏感等,结合双馈风力发电机的特性,实现精确的矢量控制。首先设计滑模面,确保系统状态在滑模面上滑动,进而设计滑模控制器以稳定系统状态,并通过反馈调整使系统跟踪期望轨迹,从而达到对双馈风力发电机的高效、稳定控制,并将抗抖振因子与幂次函数相结合设计趋近律函数,提出一种改进型幂次函数来提高控制器的性能,构建了基于改进幂次函数的滑模控制器。[结果]仿真表明,在风速突变的情况下,基于改进型幂次函数的滑模控制器控制过程几乎无超调。[结论]与传统PI调节器相比,基于改进型幂次函数的滑模控制器具有优良的动态性能和控制精度,能够在双馈风力发电系统中有效地改善控制效果,提高稳定性和抗干扰能力。 展开更多
关键词 双馈电机 矢量控制 幂次函数 滑模控制 抗干扰
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