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QUATERNIONIC SLICE REGULAR FUNCTIONS AND QUATERNIONIC LAPLACE TRANSFORMS
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作者 韩刚 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期289-302,共14页
The functions studied in the paper are the quaternion-valued functions of a quaternionic variable.It is shown that the left slice regular functions and right slice regular functions are related by a particular involut... The functions studied in the paper are the quaternion-valued functions of a quaternionic variable.It is shown that the left slice regular functions and right slice regular functions are related by a particular involution,and that the intrinsic slice regular functions play a central role in the theory of slice regular functions.The relation between left slice regular functions,right slice regular functions and intrinsic slice regular functions is revealed.As an application,the classical Laplace transform is generalized naturally to quaternions in two different ways,which transform a quaternion-valued function of a real variable to a left or right slice regular function.The usual properties of the classical Laplace transforms are generalized to quaternionic Laplace transforms. 展开更多
关键词 left slice regular function intrinsic slice regular function quaternionic Laplace Transform
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A Laurent Expansion and Residue Theorems of k-Regular Functions in Clifford Analysis 被引量:2
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作者 KU Min DU Jinyuan 《Wuhan University Journal of Natural Sciences》 CAS 2009年第2期97-102,共6页
In this context, we mainly study the behavior in the neighborhood of finite singular points for k-regular functions in R1^n with values in R0、n. We get a Laurent expansion of them in an open set, prove its uniqueness... In this context, we mainly study the behavior in the neighborhood of finite singular points for k-regular functions in R1^n with values in R0、n. We get a Laurent expansion of them in an open set, prove its uniqueness, give the definitions of k-poles, isolated and essential singular points and removable singularity, discuss some properties, and further obtain the residue theorems. 展开更多
关键词 Clifford algebra k-regular functions Laurent expansion residue theorems SINGULARITY
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THE PRODUCT OPERATOR BETWEEN BLOCH-TYPE SPACES OF SLICE REGULAR FUNCTIONS
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作者 Yuxia LIANG 《Acta Mathematica Scientia》 SCIE CSCD 2021年第5期1606-1618,共13页
There is little work concerning the properties of quaternionic operators acting on slice regular function spaces defined on quaternions.In this paper,we present an equivalent characterization for the boundedness of th... There is little work concerning the properties of quaternionic operators acting on slice regular function spaces defined on quaternions.In this paper,we present an equivalent characterization for the boundedness of the product operator C_(φ)D^(m) acting on Bloch-type spaces of slice regular functions.After that,an equivalent estimation for its essential norm is established,which can imply several existing results on holomorphic spaces. 展开更多
关键词 essential norm DIFFERENTIATION composition operator Bloch-type space slice regular functions
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The Fixed Point Theorem and the Iterative Approximation of Modified Cauchy Integral Operator of Regular Functions 被引量:1
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作者 WANG Li Ping PENG Wei Ling XIAO Zhuo Feng 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2008年第3期593-604,共12页
In the first part of this paper, we discuss the Holder continuity of the cauchy integral operator for regular functions and the relation between ‖T{f}‖α and ‖f‖α. In the second part of this paper, we introduce t... In the first part of this paper, we discuss the Holder continuity of the cauchy integral operator for regular functions and the relation between ‖T{f}‖α and ‖f‖α. In the second part of this paper, we introduce the modified cauchy integral operator T^- for regular functions. Firstly, we prove that the operator T^- has a unique fixed point by the Banach's Contraction Mapping Principle. Secondly, we give the Mann iterative sequence, and then we show the iterative sequence strongly converges to the fixed point of the operator T^-. 展开更多
关键词 real Clifford analysis regular function cauchy integral the fixed point mann iteration.
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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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Kernel matrix learning with a general regularized risk functional criterion 被引量:3
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作者 Chengqun Wang Jiming Chen +1 位作者 Chonghai Hu Youxian Sun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第1期72-80,共9页
Kernel-based methods work by embedding the data into a feature space and then searching linear hypothesis among the embedding data points. The performance is mostly affected by which kernel is used. A promising way is... Kernel-based methods work by embedding the data into a feature space and then searching linear hypothesis among the embedding data points. The performance is mostly affected by which kernel is used. A promising way is to learn the kernel from the data automatically. A general regularized risk functional (RRF) criterion for kernel matrix learning is proposed. Compared with the RRF criterion, general RRF criterion takes into account the geometric distributions of the embedding data points. It is proven that the distance between different geometric distdbutions can be estimated by their centroid distance in the reproducing kernel Hilbert space. Using this criterion for kernel matrix learning leads to a convex quadratically constrained quadratic programming (QCQP) problem. For several commonly used loss functions, their mathematical formulations are given. Experiment results on a collection of benchmark data sets demonstrate the effectiveness of the proposed method. 展开更多
关键词 kernel method support vector machine kernel matrix learning HKRS geometric distribution regularized risk functional criterion.
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APPROXIMATION ANALYSES FOR FUZZY VALUED FUNCTIONS IN L_1(μ)-NORM BY REGULAR FUZZY NEURAL NETWORKS 被引量:4
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作者 Liu Puyin (Dept. of System Eng. and Math., National Univ. of Defence Tech., Changsha 410073) 《Journal of Electronics(China)》 2000年第2期132-138,共7页
By defining fuzzy valued simple functions and giving L1(μ) approximations of fuzzy valued integrably bounded functions by such simple functions, the paper analyses by L1(μ)-norm the approximation capability of four-... By defining fuzzy valued simple functions and giving L1(μ) approximations of fuzzy valued integrably bounded functions by such simple functions, the paper analyses by L1(μ)-norm the approximation capability of four-layer feedforward regular fuzzy neural networks to the fuzzy valued integrably bounded function F : Rn → FcO(R). That is, if the transfer functionσ: R→R is non-polynomial and integrable function on each finite interval, F may be innorm approximated by fuzzy valued functions defined as to anydegree of accuracy. Finally some real examples demonstrate the conclusions. 展开更多
关键词 FUZZY VALUED simple function regular FUZZY neural network L1(μ) APPROXIMATION Universal approximator
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Correlation between Residual Renal Function and Hypertension in Regular Haemodialysis Patients 被引量:2
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作者 Said S. A. Khamis Yassein Salah +1 位作者 Nahla El-Ghalban Hany S. Elbarbary 《Open Journal of Nephrology》 2020年第3期245-253,共9页
<strong>Objective:</strong> To evaluate the correlation between residual renal function and hypertension in regular haemodialysis patients. <strong>Background:</strong> Initiating chronic dialy... <strong>Objective:</strong> To evaluate the correlation between residual renal function and hypertension in regular haemodialysis patients. <strong>Background:</strong> Initiating chronic dialysis treatment gives end-stage renal disease patients a new lease on life. However, the annual mortality rate in dialysis patients is ~20% and quality of life is substantially reduced. <strong>Patients and Methods:</strong> This study was carried out on a reasonable number of subjects on regular haemodialysis divided into two groups. All were given informed consent and, the study was approved by the ethics committee of Menoufia University. <strong>Results:</strong> There was significant relation between presence of residual renal function and hypertension in patients with ESRD on regular haemodialysis, but the relation between residual renal function and control of hypertension is not statistically significant. 40% of group 1 were hypertensive, 66.7% of group 2 patients were hypertensive, the interdialytic weight gain mean was 1.42 in group 1 and 2.37 in group 2. Control of hypertension was achieved in 63.6% of group 1 patients by one drug, 27.3% patients by 2 drugs;however 9.1% of patients need 3 drugs to control their blood pressure, while in group 2 40% of patients were controlled by one drug, 45% with 2 drugs and 15% need 3 drugs to control blood pressure. <strong>Conclusion:</strong> There is significant relation between presence of residual renal function and hypertension in patients with ESRD on regular haemodialysis, but the relation between residual renal function and control of hypertension is not statistically significant. 展开更多
关键词 HYPERTENSION regular Haemodialysis Residual Renal function
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α-times Integrated Regularized Cosine Functions and Second Order Abstract Cauchy Problems
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作者 Zhang Jizhou(张寄洲) +1 位作者 Tao Youshan(陶有山) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第1期51-54,共4页
In this paper, α-times integrated C-regularized cosine functions and mild α-times integrated C-existence families of second order are introduced. Equivalences are proved among α-times integrated C-regularized cosin... In this paper, α-times integrated C-regularized cosine functions and mild α-times integrated C-existence families of second order are introduced. Equivalences are proved among α-times integrated C-regularized cosine function for a linear operator A, C-wellposed of (α+1)-times abstract Cauchy problem and mild a -times integrated C-existence family of second order for A when the commutable condition is satisfied. In addition, if A = C-1AC, they are also equivalent to A generating the α -times integrated C-regularized cosine function. The characterization of an exponentially bounded mild α -times integrated C-existence family of second order is given out in terms of a Laplace transform. 展开更多
关键词 a-times integrated regularized cosine function mild a-times integrated C-existence family of second order C-wellposed second order abstract Cauchy problem.
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Estimation of Derivatives for Bounded Regular Vanishing Functions
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作者 GUO Yi-bing WANG Ping-an 《Chinese Quarterly Journal of Mathematics》 2018年第3期272-277,共6页
In this paper, we mainly discuss the problem of estimating the n-th derivative for bounded regular vanishing functions. The estimation of the n-th derivative for the function is deduced by the 1-th and 2-th derivative.
关键词 VANISHING function BOUNDED regular functions ESTIMATION derivative
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Investigation of the Tikhonov Regularization Method in Regional Gravity Field Modeling by Poisson Wavelets Radial Basis Functions 被引量:2
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作者 Yihao Wu Bo Zhong Zhicai Luo 《Journal of Earth Science》 SCIE CAS CSCD 2018年第6期1349-1358,共10页
The application of Tikhonov regularization method dealing with the ill-conditioned problems in the regional gravity field modeling by Poisson wavelets is studied. In particular, the choices of the regularization matri... The application of Tikhonov regularization method dealing with the ill-conditioned problems in the regional gravity field modeling by Poisson wavelets is studied. In particular, the choices of the regularization matrices as well as the approaches for estimating the regularization parameters are investigated in details. The numerical results show that the regularized solutions derived from the first-order regularization are better than the ones obtained from zero-order regularization. For cross validation, the optimal regularization parameters are estimated from L-curve, variance component estimation(VCE) and minimum standard deviation(MSTD) approach, respectively, and the results show that the derived regularization parameters from different methods are consistent with each other. Together with the firstorder Tikhonov regularization and VCE method, the optimal network of Poisson wavelets is derived, based on which the local gravimetric geoid is computed. The accuracy of the corresponding gravimetric geoid reaches 1.1 cm in Netherlands, which validates the reliability of using Tikhonov regularization method in tackling the ill-conditioned problem for regional gravity field modeling. 展开更多
关键词 regional gravity field modeling Poisson wavelets radial basis functions Tikhonov regularization method L-CURVE variance component estimation(VCE)
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Zeta Functions of the Complement and xyz-Transformations of a Regular Graph
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作者 WANG Xueqin DENG Aiping 《Journal of Donghua University(English Edition)》 EI CAS 2018年第6期480-485,共6页
Let Z(λ,G)denote the zeta function of a graph G.In this paper the complement G^Cand the G^(xyz)-transformation G^(xyz)of an r-regular graph G with n vertices and m edges for x,y,z∈{0,1,+,-},are considerd.The relatio... Let Z(λ,G)denote the zeta function of a graph G.In this paper the complement G^Cand the G^(xyz)-transformation G^(xyz)of an r-regular graph G with n vertices and m edges for x,y,z∈{0,1,+,-},are considerd.The relationship between Z(λ,G)and Z(λ,G^C)is obtained.For all x,y,z∈{0,1,+,-},the explicit formulas for the reciprocal of Z(λ,G^(xyz))in terms of r,m,n and the characteristic polynomial of G are obtained.Due to limited space,only the expressions for G^(xyz)with z=0,and xyz∈{0++,+++,1+-}are presented here. 展开更多
关键词 regular graph COMPLEMENT xyz-transformation ZETA function
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The Ill-Posedness of Derivative Interpolation and Regularized Derivative Interpolation for Non-Bandlimited Functions
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作者 Weidong Chen 《Applied Mathematics》 2022年第1期87-100,共14页
In this paper, the ill-posedness of derivative interpolation is discussed, and a regularized derivative interpolation for non-bandlimited signals is presented. The convergence of the regularized derivative interpolati... In this paper, the ill-posedness of derivative interpolation is discussed, and a regularized derivative interpolation for non-bandlimited signals is presented. The convergence of the regularized derivative interpolation is studied. The numerical results are given and compared with derivative interpolation using the Tikhonov regularization method. The regularized derivative interpolation in this paper is more accurate in computation. 展开更多
关键词 Nonband-Limited function Derivative Interpolation ILL-POSEDNESS regularIZATION
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一种基于改进梯度裁剪与门控循环单元的软测量算法
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作者 高超 孙凯 《齐鲁工业大学学报》 2025年第4期61-69,共9页
在现代工业过程中,由于系统的非线性、时延问题以及异常值的存在,使用基础的数据驱动模型对关键性能指标的准确预测显得较为困难。提出了一种鲁棒的混合网络软测量算法,该混合网络模型以神经常微分方程网络为核心,辅以门控循环单元的结... 在现代工业过程中,由于系统的非线性、时延问题以及异常值的存在,使用基础的数据驱动模型对关键性能指标的准确预测显得较为困难。提出了一种鲁棒的混合网络软测量算法,该混合网络模型以神经常微分方程网络为核心,辅以门控循环单元的结构,以强化对连续数据的动态建模能力和提高对时序数据的分析精度。首先,使用基于常微分方程的门控循环单元作为处理非线性数据的基础模型。其次,设计了一种动态的梯度裁剪方法,将其与权重裁剪相结合引入到模型的训练过程中,以保证模型训练的稳定性和收敛性。此后,使用一种截断的Huber损失函数,并将其与弹性正则化相结合以处理异常值。最后,利用数值仿真和工业数据集对所提算法进行验证。结果表明,该算法可以有效的提高模型的预测精度和模型的稳定性。 展开更多
关键词 软测量 门控循环单元 梯度裁剪 鲁棒损失函数 弹性正则化
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规则截面无限长柱体的光散射研究
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作者 颜兵 张华永 +1 位作者 陈平 刘晨华 《激光技术》 北大核心 2025年第1期62-66,共5页
为了研究任意规则截面的无限长柱体对入射光束的散射特性,提出了一种半解析方法。采用适当的圆柱矢量波函数来展开散射场和内场,通过电磁场边界条件和投影法确定展开系数;以基模高斯光束和径向环状光束照射横截面为圆形、椭圆形和矩形... 为了研究任意规则截面的无限长柱体对入射光束的散射特性,提出了一种半解析方法。采用适当的圆柱矢量波函数来展开散射场和内场,通过电磁场边界条件和投影法确定展开系数;以基模高斯光束和径向环状光束照射横截面为圆形、椭圆形和矩形的无限长柱体为例,对归一化的近场强度分布进行了数值仿真。结果表明,光束经过圆柱和椭圆柱传输后发生明显的干涉现象,而矩形柱对光束具有一定的汇聚作用。该研究为求解任意规则横截面的无限长柱体对任意光束的散射提供了一个应用方便的半解析解。 展开更多
关键词 散射 干涉现象 半解析方法 规则截面无限长柱体 圆柱矢量波函数 归一化场强分布
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基于一致性功能神经过程的多视图时序预测
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作者 杨春霞 蒋耀 +1 位作者 翟雪彤 周媛媛 《计算机工程》 北大核心 2025年第10期111-120,共10页
在多视图时间序列预测领域,如何有效融合来自不同视图的信息,是一个重要且具有挑战性的问题。现有的多视图时序预测方法在捕获历史数据趋势方面存在局限性,同时也常受到多视图信息分布不一致的影响。针对这两个问题,基于功能神经过程(F... 在多视图时间序列预测领域,如何有效融合来自不同视图的信息,是一个重要且具有挑战性的问题。现有的多视图时序预测方法在捕获历史数据趋势方面存在局限性,同时也常受到多视图信息分布不一致的影响。针对这两个问题,基于功能神经过程(FNP)框架,提出一种一致性功能神经过程(CFNP)框架。CFNP框架中包含两个核心模块:视图随机相关图模块和视图分布对齐模块。视图随机相关图模块通过分析历史数据的分布,辅助对当前数据的理解和预测;而视图分布对齐模块致力于缩小不同视图间的概率分布差异,通过在潜在空间中施加约束,提高模型对时间序列内在关联性的捕捉能力。在两个公开数据集上的实验结果表明,相比于现有方法,CFNP框架在均方根误差(RMSE)上性能提升分别为14%和5%,证明此框架能够更准确地预测多视图时间序列。 展开更多
关键词 多视图学习 时序预测 概率预测 功能神经过程 一致性正则化
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基于正则判别与样条回归的红外光谱微量物证鉴定研究
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作者 王星 赵玉冰 +1 位作者 李杰 王元凤 《数理统计与管理》 北大核心 2025年第3期436-450,共15页
红外吸收光谱是法庭科学领域将犯罪现场中微量物证和非物证进行正确识别的重要技术。文章针对具有重复观测量小、高维、宽谱带且图像十分相近不易区分的红外光谱数据,提出了正则判别与函数型数据分析相结合的模型,该模型将用于有效波数... 红外吸收光谱是法庭科学领域将犯罪现场中微量物证和非物证进行正确识别的重要技术。文章针对具有重复观测量小、高维、宽谱带且图像十分相近不易区分的红外光谱数据,提出了正则判别与函数型数据分析相结合的模型,该模型将用于有效波数和波数带提取的双重分析目标。通过真实公开的基础材料含量有微小差异的油漆案例数据,开展了模型性能的实证研究,研究发现:(1)与常用的主成分分析降噪,广义线性套索路径法相比,正则判别有助于红外光谱标志性特征的提取,具有提取的特征准确度高和物证区分精度高的双稳健良好性能;(2)在提取标志性特征的基础上,进一步运用函数型数据分析中的同时置信带方法,通过样条回归估计协方差函数估计局部分段连续光谱波段。实验结果表明:正则判别与函数型数据分析的结合用于红外光谱稀疏标志特征的提取,精准鉴别不同物证和定量估计局部分段连续光谱段方面是行之有效的。 展开更多
关键词 独立正则判别 样条回归 质心收缩算法 红外吸收光谱 均值函数估计
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非凸多目标优化问题有效解集的非空性与有界性的渐近刻画
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作者 刘应 傅小恒 唐莉萍 《应用数学和力学》 北大核心 2025年第4期519-527,共9页
优化问题解集的非空性和有界性在数值算法研究中发挥着重要作用.该文利用渐近分析工具,在正则性条件下研究了非凸多目标优化问题有效解集的非空性和有界性.首先,在正则条件下,建立了非凸多目标优化问题的有效解集和真有效解集的内外渐... 优化问题解集的非空性和有界性在数值算法研究中发挥着重要作用.该文利用渐近分析工具,在正则性条件下研究了非凸多目标优化问题有效解集的非空性和有界性.首先,在正则条件下,建立了非凸多目标优化问题的有效解集和真有效解集的内外渐近估计;然后,根据这些估计,获得了非凸多目标优化问题有效解集的非空有界性的渐近刻画;最后,给出了非凸多目标优化问题有效解存在的必要条件. 展开更多
关键词 非凸多目标优化问题 有效解 正则性 渐近锥 渐近函数
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基于传递函数的高速受电弓跟随性研究
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作者 孔令楠 周宁 +3 位作者 程尧 蒋聪健 孙翌 张卫华 《铁道科学与工程学报》 北大核心 2025年第2期533-542,共10页
随着列车运行速度的提升,对列车弓网系统的动态性能要求不断提高,受电弓的跟随性作为动力学指标之一直接影响弓网的动态接触性能与受流质量。为厘清高速受电弓的跟随性随受电弓参数变化的机理,进而改善弓网动力学性能,首先推导受电弓三... 随着列车运行速度的提升,对列车弓网系统的动态性能要求不断提高,受电弓的跟随性作为动力学指标之一直接影响弓网的动态接触性能与受流质量。为厘清高速受电弓的跟随性随受电弓参数变化的机理,进而改善弓网动力学性能,首先推导受电弓三质量块等效模型的传递函数;然后以此为基础初次建立了反映受电弓跟随性能的全新数学理论模型,并结合数值仿真与台架试验结果验证模型的合理性;最后基于该模型运用仿真计算、理论推导与灵敏度分析得到在1.5~12 Hz激振频率下跟随性的影响规律。研究结果表明:受电弓跟随性的极大值发生在受电弓反向共振频率,即2阶固有频率段。弓头、上框架的等效质量、刚度、阻尼和下框架的等效刚度与跟随性呈负相关;下框架的等效质量、阻尼与跟随性呈正相关。弓头和框架的等效质量与跟随性极值频率呈负相关;等效刚度与跟随性极值频率呈正相关。灵敏度分析显示弓头和框架的等效质量对跟随性影响较大,变化率数量级为10^(0)~10^(1);其次是等效阻尼,变化率数量级为10^(-2)~10^(-1);最后是等效刚度,变化率数量级普遍低于10^(-3),下框架的等效刚度改变几乎不影响跟随性。研究结果提供了一种较精确的受电弓跟随性数学模型,并详细展示了受电弓各等效参数变化对跟随性的影响率,为跟随性的进一步优化提供了理论参考。 展开更多
关键词 高速受电弓 受流质量 传递函数 跟随性 规律分析
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基于核密度估计的图像生成模型评价方法
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作者 李磊 庞玉碟 +2 位作者 吴长兰 殷永 谭宏卫 《自动化应用》 2025年第4期6-10,共5页
如何科学且客观地评价深度图像生成模型的性能是一个极具挑战性的问题。经典评价方法FID受限于高斯假设,易导致评价失真且计算复杂度较高。为解决该问题,提出一种分布自由的图像生成模型评价方法。具体地,通过在特征空间中利用核密度估... 如何科学且客观地评价深度图像生成模型的性能是一个极具挑战性的问题。经典评价方法FID受限于高斯假设,易导致评价失真且计算复杂度较高。为解决该问题,提出一种分布自由的图像生成模型评价方法。具体地,通过在特征空间中利用核密度估计拟合一个混合高斯分布,在此基础上计算Fréchet距离,并引入记忆正则函数来量化模型的过拟合程度,以解决FID的高斯假设和无法检测过拟合问题。实验结果表明,该评价方法不仅在多个数据集上与FID展现出高度一致性,而且在计算效率上也实现了优化。 展开更多
关键词 深度图像生成模型 性能评价 感知空间 高斯混合密度估计器 记忆正则函数
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