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Prediction and Output Estimation of Pattern Moving in Non-Newtonian Mechanical Systems Based on Probability Density Evolution
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作者 Cheng Han Zhengguang Xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期515-536,共22页
A prediction framework based on the evolution of pattern motion probability density is proposed for the output prediction and estimation problem of non-Newtonian mechanical systems,assuming that the system satisfies t... A prediction framework based on the evolution of pattern motion probability density is proposed for the output prediction and estimation problem of non-Newtonian mechanical systems,assuming that the system satisfies the generalized Lipschitz condition.As a complex nonlinear system primarily governed by statistical laws rather than Newtonian mechanics,the output of non-Newtonian mechanics systems is difficult to describe through deterministic variables such as state variables,which poses difficulties in predicting and estimating the system’s output.In this article,the temporal variation of the system is described by constructing pattern category variables,which are non-deterministic variables.Since pattern category variables have statistical attributes but not operational attributes,operational attributes are assigned to them by posterior probability density,and a method for analyzing their motion laws using probability density evolution is proposed.Furthermore,a data-driven form of pattern motion probabilistic density evolution prediction method is designed by combining pseudo partial derivative(PPD),achieving prediction of the probability density satisfying the system’s output uncertainty.Based on this,the final prediction estimation of the system’s output value is realized by minimum variance unbiased estimation.Finally,a corresponding PPD estimation algorithm is designed using an extended state observer(ESO)to estimate the parameters to be estimated in the proposed prediction method.The effectiveness of the parameter estimation algorithm and prediction method is demonstrated through theoretical analysis,and the accuracy of the algorithm is verified by two numerical simulation examples. 展开更多
关键词 Non-newtonian mechanical systems prediction and estimation pattern moving probability density evolution pseudo partial derivative
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Multivariate form of Hermite sampling series
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作者 Rashad M.Asharabi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期253-265,共13页
In this paper,we establish a new multivariate Hermite sampling series involving samples from the function itself and its mixed and non-mixed partial derivatives of arbitrary order.This multivariate form of Hermite sam... In this paper,we establish a new multivariate Hermite sampling series involving samples from the function itself and its mixed and non-mixed partial derivatives of arbitrary order.This multivariate form of Hermite sampling will be valid for some classes of multivariate entire functions,satisfying certain growth conditions.We will show that many known results included in Commun Korean Math Soc,2002,17:731-740,Turk J Math,2017,41:387-403 and Filomat,2020,34:3339-3347 are special cases of our results.Moreover,we estimate the truncation error of this sampling based on localized sampling without decay assumption.Illustrative examples are also presented. 展开更多
关键词 multidimensional sampling series sampling with partial derivatives contour integral truncation error
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Space Topologies and Their Dual Space Topologies for Conventional Functional Space Topologies
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作者 Mahjoub A. Elamin 《Journal of Applied Mathematics and Physics》 2024年第3期778-804,共27页
In this paper, we have studied the topology of some classical functional spaces. Among these spaces, there are standard spaces, spaces that can be metrizable and others that cannot be metrizable. But they are all topo... In this paper, we have studied the topology of some classical functional spaces. Among these spaces, there are standard spaces, spaces that can be metrizable and others that cannot be metrizable. But they are all topological vector spaces and it is in this context that we have chosen to present this work. We are interested in the topology of its spaces and in the topologies of their dual spaces. The first part, we presented the fundamental topological properties of topological vector spaces. The second part, we studied Frechet spaces and particularly the space S(R<sup>n</sup>) of functions of class C<sup>∞ </sup>on R<sup>n</sup> which are as well as all their rapidly decreasing partial derivatives. We have also studied its dual S'(Rn</sup>) the space of tempered distributions. The last part aims to define a topological structure on an increasing union of Frechet spaces called inductive limit of Frechet spaces. We study in particular the space D(Ω) of functions of class C<sup>∞</sup> with compact supports on Ω as well as its dual D' (Ω) the space distributions over the open set Ω. 展开更多
关键词 Linear Forms Dual Spaces Frechet Spaces partial Derivatives DISTRIBUTIONS Topological Structure Weak Topology Strong Topology
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Importance Analysis of a Multi-state System Based on Direct Partial Logic Derivatives and Multi-valued Decision Diagrams 被引量:1
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作者 古莹奎 李晶 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期789-792,共4页
Importance analysis quantifies the critical degree of individual component. Compared with the traditional binary state system,importance analysis of the multi-state system is more aligned with the practice. Because th... Importance analysis quantifies the critical degree of individual component. Compared with the traditional binary state system,importance analysis of the multi-state system is more aligned with the practice. Because the multi-valued decision diagram( MDD) can reflect the relationship between the components and the system state bilaterally, it was introduced into the reliability calculation of the multi-state system( MSS). The building method,simplified criteria,and path search and probability algorithm of MSS structure function MDD were given,and the reliability of the system was calculated. The computing methods of importance based on MDD and direct partial logic derivatives( DPLD) were presented. The diesel engine fuel supply system was taken as an example to illustrate the proposed method. The results show that not only the probability of the system in each state can be easily obtained,but also the influence degree of each component and its state on the system reliability can be obtained,which is conducive to the condition monitoring and structure optimization of the system. 展开更多
关键词 multi-state system(MSS) importance analysis reliability multi-valued decision diagram(MDD) direct partial logic derivative(DPLD) diesel engine fuel supply system
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Solution of Partial Derivative Equations of Poisson and Klein-Gordon with Neumann Conditions as a Generalized Problem of Two-Dimensional Moments
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作者 Maria B. Pintarelli 《Journal of Applied Mathematics and Physics》 2020年第8期1606-1614,共9页
It will be shown that finding solutions from the Poisson and Klein-Gordon equations under Neumann conditions are equivalent to solving an integral equation, which can be treated as a generalized two-dimensional moment... It will be shown that finding solutions from the Poisson and Klein-Gordon equations under Neumann conditions are equivalent to solving an integral equation, which can be treated as a generalized two-dimensional moment problem over a domain that is considered rectangular. The method consists to solve the integral equation numerically using the two-dimensional inverse moments problem techniques. We illustrate the different cases with examples. 展开更多
关键词 Equation in Poisson partial Derivatives Klein-Gordon Equation Integral Equations Generalized Moment Problem
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Dimension decomposition algorithm for multiple source localization using uniform circular array 被引量:1
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作者 SU Xiaolong HU Panhe +3 位作者 WEI Zhenhua LIU Zhen SHI Junpeng LI Xiang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第3期650-660,共11页
A dimension decomposition(DIDE)method for multiple incoherent source localization using uniform circular array(UCA)is proposed.Due to the fact that the far-field signal can be considered as the state where the range p... A dimension decomposition(DIDE)method for multiple incoherent source localization using uniform circular array(UCA)is proposed.Due to the fact that the far-field signal can be considered as the state where the range parameter of the nearfield signal is infinite,the algorithm for the near-field source localization is also suitable for estimating the direction of arrival(DOA)of far-field signals.By decomposing the first and second exponent term of the steering vector,the three-dimensional(3-D)parameter is transformed into two-dimensional(2-D)and onedimensional(1-D)parameter estimation.First,by partitioning the received data,we exploit propagator to acquire the noise subspace.Next,the objective function is established and partial derivative is applied to acquire the spatial spectrum of 2-D DOA.At last,the estimated 2-D DOA is utilized to calculate the phase of the decomposed vector,and the least squares(LS)is performed to acquire the range parameters.In comparison to the existing algorithms,the proposed DIDE algorithm requires neither the eigendecomposition of covariance matrix nor the search process of range spatial spectrum,which can achieve satisfactory localization and reduce computational complexity.Simulations are implemented to illustrate the advantages of the proposed DIDE method.Moreover,simulations demonstrate that the proposed DIDE method can also classify the mixed far-field and near-field signals. 展开更多
关键词 source localization parameter estimation uniform circular array(UCA) PROPAGATOR partial derivative least squares(LS)
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Improved High Order Model-Free Adaptive Iterative Learning Control with Disturbance Compensation and Enhanced Convergence
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作者 Zhiguo Wang Fangqing Gao Fei Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第1期343-355,共13页
In this paper,an improved high-order model-free adaptive iterative control(IHOMFAILC)method for a class of nonlinear discrete-time systems is proposed based on the compact format dynamic linearization method.This meth... In this paper,an improved high-order model-free adaptive iterative control(IHOMFAILC)method for a class of nonlinear discrete-time systems is proposed based on the compact format dynamic linearization method.This method adds the differential of tracking error in the criteria function to compensate for the effect of the random disturbance.Meanwhile,a high-order estimation algorithmis used to estimate the value of pseudo partial derivative(PPD),that is,the current value of PPD is updated by that of previous iterations.Thus the rapid convergence of the maximumtracking error is not limited by the initial value of PPD.The convergence of the maximumtracking error is deduced in detail.This method can track the desired output with enhanced convergence and improved tracking performance.Two examples are used to verify the convergence and effectiveness of the proposed method. 展开更多
关键词 Pseudo partial derivative enhanced convergence tracking error disturbance compensation
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Sensitivity Analysis of Radial Basis Function Networks for River Stage Forecasting
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作者 Christian Walker Dawson 《Journal of Software Engineering and Applications》 2020年第12期327-347,共21页
<div style="text-align:justify;"> <span style="font-family:Verdana;">Sensitivity analysis of neural networks to input variation is an important research area as it goes some way to addr... <div style="text-align:justify;"> <span style="font-family:Verdana;">Sensitivity analysis of neural networks to input variation is an important research area as it goes some way to addressing the criticisms of their black-box behaviour. Such analysis of RBFNs for hydrological modelling has previously been limited to exploring perturbations to both inputs and connecting weights. In this paper, the backward chaining rule that has been used for sensitivity analysis of MLPs, is applied to RBFNs and it is shown how such analysis can provide insight into physical relationships. A trigonometric example is first presented to show the effectiveness and accuracy of this approach for first order derivatives alongside a comparison of the results with an equivalent MLP. The paper presents a real-world application in the modelling of river stage shows the importance of such approaches helping to justify and select such models.</span> </div> 展开更多
关键词 Artificial Neural Networks Backward Chaining Multi-Layer Perceptron partial Derivative Radial Basis Function Sensitivity Analysis River Stage Forecasting
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Clustering for Bivariate Functional Data
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作者 Shi-yun CAO Yan-qiu ZHOU +1 位作者 Yan-ling WAN Tao ZHANG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2024年第3期613-629,共17页
In this paper,we consider the clustering of bivariate functional data where each random surface consists of a set of curves recorded repeatedly for each subject.The k-centres surface clustering method based on margina... In this paper,we consider the clustering of bivariate functional data where each random surface consists of a set of curves recorded repeatedly for each subject.The k-centres surface clustering method based on marginal functional principal component analysis is proposed for the bivariate functional data,and a novel clustering criterion is presented where both the random surface and its partial derivative function in two directions are considered.In addition,we also consider two other clustering methods,k-centres surface clustering methods based on product functional principal component analysis or double functional principal component analysis.Simulation results indicate that the proposed methods have a nice performance in terms of both the correct classification rate and the adjusted rand index.The approaches are further illustrated through empirical analysis of human mortality data. 展开更多
关键词 bivariate functional data -centres surface clustering functional principal component analysis partial derivative function
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Estimation of partial derivative functionals with application to human mortality data analysis 被引量:1
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作者 Tao Zhang Zhaohai Li +1 位作者 Aiyi Liu Qingzhao Zhang 《Science China Mathematics》 SCIE CSCD 2021年第9期2117-2140,共24页
To better describe and understand the time dynamics in functional data analysis,it is often desirable to recover the partial derivatives of the random surface.A novel approach is proposed based on marginal functional ... To better describe and understand the time dynamics in functional data analysis,it is often desirable to recover the partial derivatives of the random surface.A novel approach is proposed based on marginal functional principal component analysis to derive the representation for partial derivatives.To obtain the Karhunen-Lo`eve expansion of the partial derivatives,an adaptive estimation is explored.Asymptotic results of the proposed estimates are established.Simulation studies show that the proposed methods perform well in finite samples.Application to the human mortality data reveals informative time dynamics in mortality rates. 展开更多
关键词 bivariate functional data functional principal component analysis MORTALITY partial derivatives
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A new online modelling method for aircraft engine state space model 被引量:1
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作者 Shuwei PANG Qiuhong LI Haibo ZHANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第6期1756-1773,共18页
To overcome the drawbacks of current modelling method for aircraft engine state space model,a new method is introduced.The form of state space model is derived by using Talyor series to expand the nonlinear model that... To overcome the drawbacks of current modelling method for aircraft engine state space model,a new method is introduced.The form of state space model is derived by using Talyor series to expand the nonlinear model that is implicit equations and involves many iterations.A partial derivative calculation method for iterations is developed to handle the influence of iterations on parameters.The derivative calculation and the aerothermodynamics calculations are combined in the component level model with fixed number Newton-Raphson(N-R)iterations.Mathematical derivation and simulations show the convergence ability of proposed method.Simulations show that comparing with the linear parameter varying model and centered difference based state space model,much higher accuracy of proposed online modelling method is achieved.The accuracy of the state space model built by proposed method can be maintained when the step amplitudes of inputs are within 2%,and the responses of the state space model can match those of the component level model when each input steps larger amplitudes.In addition,an online verification was carried out to show the capability of modelling at any operating point and that state space model can predict future outputs accurately.Thus,the effectiveness of the proposed method is demonstrated. 展开更多
关键词 Aircraft engines Component level model Online modelling partial derivative State space models
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Stochastic Boundary Element Analysis of Concrete Gravity Dam 被引量:1
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作者 张明 吴清高 《Tsinghua Science and Technology》 SCIE EI CAS 2002年第3期254-257,共4页
Stochastic boundary integral equations for analyzing large structures are obtained from the partial derivatives of basic random variables. A stochastic boundary element method based on the equations is developed to s... Stochastic boundary integral equations for analyzing large structures are obtained from the partial derivatives of basic random variables. A stochastic boundary element method based on the equations is developed to solve engineering problems of gravity dams using random factors including material parameters of the dam body and the foundation, the water level in the upper reaches, the anti-slide friction coefficient of the dam base, etc. A numerical example shows that the stochastic boundary element method presented in this paper to calculate the reliability index of large construction projects such as a large concrete gravity dam has the advantages of less input data and more precise computational results. 展开更多
关键词 stochastic boundary element random variable partial derivatives reliability index gravity dam
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Remarks on the Regularity Criteria of Weak Solutions to the Three-dimensional Micropolar Fluid Equations 被引量:1
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作者 Yan JIA Xing-wei ZHANG +1 位作者 Wen-liang ZHANG Bo-qing DONG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2013年第4期869-880,共12页
This paper is investigate the regularity criteria of weak solutions to the three-dimensional microp- olar fluid equations. Several sufficient conditions in terms of some partial derivatives of the velocity or the pres... This paper is investigate the regularity criteria of weak solutions to the three-dimensional microp- olar fluid equations. Several sufficient conditions in terms of some partial derivatives of the velocity or the pressure are obtained. 展开更多
关键词 Micropolar fluid equations regularity criteria partial derivatives Lorentz spaces
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Study of Model-free Adaptive Data-driven SMC Algorithm 被引量:1
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作者 Wei Hu Jie Tang 《International Journal of Automation and computing》 EI CSCD 2016年第2期183-190,共8页
A kind of adaptive sliding model control algorithm is developed to solve and improve the mathematical model dependency and un-modeled dynamics of a controlled system. The control strategy derived from a kind of data-d... A kind of adaptive sliding model control algorithm is developed to solve and improve the mathematical model dependency and un-modeled dynamics of a controlled system. The control strategy derived from a kind of data-driven control method in essence, thereby the input and output data are utilized by the controller with no information about the control system model. Theoretical analysis proves that this proposed control algorithm can improve the utilization of the estimated pseudo partial derivative information and accelerate the velocity of the convergence. The stability of the control system is further verified by rigorous mathematical analysis. This new discrete-time nonlinear systems model-free control algorithm obtained better control performance through the simulations for the linear motor position and the information tracking speed, which also achieved robust and accurate traceability. 展开更多
关键词 Nonlinear system model-free adaptive control sliding mode control control law pseudo partial derivative
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A rapid compensation method for launch data of long-range rockets under influence of the Earth's disturbing gravity field 被引量:2
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作者 Baolin MA Hongbo ZHANG +1 位作者 Wei ZHENG Jie WU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第3期1196-1203,共8页
Regarding the rapid compensation of the influence of the Earth' s disturbing gravity field upon trajectory calculation,the key point lies in how to derive the analytical solutions to the partial derivatives of the st... Regarding the rapid compensation of the influence of the Earth' s disturbing gravity field upon trajectory calculation,the key point lies in how to derive the analytical solutions to the partial derivatives of the state of burnout point with respect to the launch data.In view of this,this paper mainly expounds on two issues:one is based on the approximate analytical solution to the motion equation for the vacuum flight section of a long-range rocket,deriving the analytical solutions to the partial derivatives of the state of burnout point with respect to the changing rate of the finalstage pitch program;the other is based on the initial positioning and orientation error propagation mechanism,proposing the analytical calculation formula for the partial derivatives of the state of burnout point with respect to the launch azimuth.The calculation results of correction data are simulated and verified under different circumstances.The simulation results are as follows:(1) the accuracy of approximation between the analytical solutions and the results attained via the difference method is higher than 90%,and the ratio of calculation time between them is lower than 0.2%,thus demonstrating the accuracy of calculation of data corrections and advantages in calculation speed;(2) after the analytical solutions are compensated,the longitudinal landing deviation of the rocket is less than 20 m and the lateral landing deviation of the rocket is less than 10 m,demonstrating that the corrected data can meet the requirements for the hit accuracy of a long-range rocket. 展开更多
关键词 Analytical solution Earth's disturbing gravity field Launch data partial derivative compensation method Rapid compensation
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Theory and Applications of Distinctive Conformable Triple Laplace and Sumudu Transforms Decomposition Methods
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作者 BHANOTAR Shailesh A BELGACEM Fethi Bin Muhammad 《Journal of Partial Differential Equations》 CSCD 2022年第1期49-77,共29页
This article presents some important results of conformable fractional partial derivatives.The conformable triple Laplace and Sumudu transform are coupled with the Adomian decomposition method where a new method is pr... This article presents some important results of conformable fractional partial derivatives.The conformable triple Laplace and Sumudu transform are coupled with the Adomian decomposition method where a new method is proposed to solve nonlinear partial differential equations in 3-space.Moreover,mathematical experiments are provided to verify the performance of the proposed method.A fundamental question that is treated in this work:is whether using the Laplace and Sumudu transforms yield the same results?This question is amply answered in the realm of the proposed applications. 展开更多
关键词 Riemann-Liouville fractional integral fractional derivative Adomian decomposition method conformable fractional partial derivative conformable triple Laplace and Sumudu transform
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