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EXISTENCE RESULT FOR FRACTIONAL STATE-DEPENDENT SWEEPING PROCESSES
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作者 Shengda ZENG Abderrahim BOUACH Tahar HADDAD 《Acta Mathematica Scientia》 2025年第4期1471-1481,共11页
This paper addresses the evolution problem governed by the fractional sweeping process with prox-regular nonconvex constraints.The values of the moving set are time and state-dependent.The aim is to illustrate how a f... This paper addresses the evolution problem governed by the fractional sweeping process with prox-regular nonconvex constraints.The values of the moving set are time and state-dependent.The aim is to illustrate how a fixed point method can establish an existence theorem for this fractional nonlinear evolution problem.By combining Schauder’s fixed point theorem with a well-posedness theorem when the set C is independent of the state u(i.e.C:=C(t),as presented in[22,23]),we prove the existence of a solution to our quasi-variational fractional sweeping process in infinite-dimensional Hilbert spaces.Similar to the conventional state-dependent sweeping process,achieving this result requires a condition on the size of the Lipschitz constant of the moving set relative to the state. 展开更多
关键词 fractional differential inclusion Moreau's sweeping process prox-regular sets fixed point
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Existence for neutral fractional differential equations in composite relaxation process
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作者 HE Jia-wei YU Zi-cheng 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第2期343-358,共16页
This paper is devoted to the existence results for a class of neutral abstract fractional differential equations involving the composite relaxation process.Based on the Laplace transform,the semigroup theory and the W... This paper is devoted to the existence results for a class of neutral abstract fractional differential equations involving the composite relaxation process.Based on the Laplace transform,the semigroup theory and the Wright functions,we first introduce a definition of mild solutions to the considered problem.By means of the noncompactness of measure and the fixed point technique,we establish existence criteria of solutions.Finally,an example is presented to illustrate our main result. 展开更多
关键词 Caputo fractional derivative composite relaxation process noncompactness of measure
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Pricing Study on Two Kinds of Power Options in Jump-Diffusion Models with Fractional Brownian Motion and Stochastic Rate
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作者 Jin Li Kaili Xiang Chuanyi Luo 《Applied Mathematics》 2014年第16期2426-2441,共16页
In this paper, under the assumption that the exchange rate follows the extended Vasicek model, the pricing of the reset option in FBM model is investigated. Some interesting themes such as closed-form formulas for the... In this paper, under the assumption that the exchange rate follows the extended Vasicek model, the pricing of the reset option in FBM model is investigated. Some interesting themes such as closed-form formulas for the reset option with a single reset date and the phenomena of delta of the reset jumps existing in the reset option during the reset date are discussed. The closed-form formulae of pricing for two kinds of power options are derived in the end. 展开更多
关键词 STOCHASTIC RATE fractional jump-diffusion process fractional BROWN Motion Power OPTION
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The exact solution of Stokes' second problem including start-up process with fractional element 被引量:3
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作者 Kaixin Hu Keqin Zhu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第5期577-582,共6页
The start-up process of Stokes' second problem of a viscoelastic material with fractional element is studied. The fluid above an infinite flat plane is set in motion by a sudden acceleration of the plate to steady os... The start-up process of Stokes' second problem of a viscoelastic material with fractional element is studied. The fluid above an infinite flat plane is set in motion by a sudden acceleration of the plate to steady oscillation. Exact solutions are obtained by using Laplace transform and Fourier transform. It is found that the relationship between the first peak value and the one of equal-amplitude oscillations depends on the distance from the plate. The amplitude decreases for increasing frequency and increasing distance. 展开更多
关键词 Stokes' second problem Start-up process fractional element Laplace transform Fourier transform
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LEAST SQUARES ESTIMATION FOR ORNSTEIN-UHLENBECK PROCESSES DRIVEN BY THE WEIGHTED FRACTIONAL BROWNIAN MOTION 被引量:3
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作者 申广君 尹修伟 闫理坦 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期394-408,共15页
In this article, we study a least squares estimator (LSE) of θ for the Ornstein- Uhlenbeck process X0=0,dXt=θXtdt+dBt^ab, t ≥ 0 driven by weighted fractional Brownian motion B^a,b with parameters a, b. We obtain... In this article, we study a least squares estimator (LSE) of θ for the Ornstein- Uhlenbeck process X0=0,dXt=θXtdt+dBt^ab, t ≥ 0 driven by weighted fractional Brownian motion B^a,b with parameters a, b. We obtain the consistency and the asymptotic distribution of the LSE based on the observation {Xs, s∈[0,t]} as t tends to infinity. 展开更多
关键词 Weighted fractional Brownian motion least squares estimator Ornstein-Uhl-enbeck process
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ON COLLISION LOCAL TIME OF TWO INDEPENDENT FRACTIONAL ORNSTEIN-UHLENBECK PROCESSES 被引量:2
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作者 郭精军 李楚进 《Acta Mathematica Scientia》 SCIE CSCD 2017年第2期316-328,共13页
In this article, we study the existence of collision local time of two indepen- dent d-dimensional fractional Ornstein-Uhlenbeck processes X+^H1 and Xt^H2 with different parameters Hi ∈ (0, 1),i = 1, 2. Under the ... In this article, we study the existence of collision local time of two indepen- dent d-dimensional fractional Ornstein-Uhlenbeck processes X+^H1 and Xt^H2 with different parameters Hi ∈ (0, 1),i = 1, 2. Under the canonical framework of white noise analysis, we characterize the collision local time as a Hida distribution and obtain its' chaos expansion. Key words Collision local time; fractional Ornstein-Uhlenbeck processes; generalized white noise functionals; choas expansion 展开更多
关键词 Collision local time fractional Ornstein-Uhlenbeck processes generalized white noise functionals choas expansion
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Machine learning for prediction of retained austenite fraction and optimization of processing in quenched and partitioned steels
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作者 Shuai Wang Jie Li +3 位作者 Li-yang Zeng Xun-wei Zuo Nai-lu Chen Yong-hua Rong 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2024年第8期2002-2013,共12页
The metastable retained austenite(RA)plays a significant role in the excellent mechanical performance of quenching and partitioning(Q&P)steels,while the volume fraction of RA(V_(RA))is challengeable to directly pr... The metastable retained austenite(RA)plays a significant role in the excellent mechanical performance of quenching and partitioning(Q&P)steels,while the volume fraction of RA(V_(RA))is challengeable to directly predict due to the complicated relationships between the chemical composition and process(like quenching temperature(Qr)).A Gaussian process regression model in machine learning was developed to predict V_(RA),and the model accuracy was further improved by introducing a metallurgical parameter of martensite fraction(fo)to accurately predict V_(RA) in Q&P steels.The developed machine learning model combined with Bayesian global optimization can serve as another selection strategy for the quenching temperature,and this strategy is very effcient as it found the"optimum"Qr with the maximum V_(RA) using only seven consecutive iterations.The benchmark experiment also reveals that the developed machine learning model predicts V_(RA) more accurately than the popular constrained carbon equilibrium thermodynamic model,even better than a thermo-kinetic quenching-partitioning-tempering-local equilibrium model. 展开更多
关键词 Q&P steel Retained austenite fraction Machine learning Quenching temperature Gaussian process regression model
原文传递
ERRATUM TO: LEAST SQUARES ESTIMATION FOR ORNSTEIN-UHLENBECK PROCESSES DRIVEN BY THE WEIGHTED FRACTIONAL BROWNIAN MOTION (ACTA MATHEMATICA SCIENTIA 2016,36B (2) :394-408) 被引量:1
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作者 申广君 尹修伟 闫理坦 《Acta Mathematica Scientia》 SCIE CSCD 2017年第4期1173-1176,共4页
We give a correction of Theorem 2.2 of Shen, Yin and Yan (2016).
关键词 weighted fractional Brownian motion least squares estimator Ornstein-Uhlenbeck process
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A GENERAL FORM OF THE INCREMENTS OF TWO-PARAMETER FRACTIONAL WIENER PROCESS 被引量:1
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作者 Lu Chuanrong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第3期331-337,共7页
A general form of the increments of two-parameter fractional Wiener process is given. The results of Csoergo-Révész increments are a special case,and it also implies the results of the increments of the two-... A general form of the increments of two-parameter fractional Wiener process is given. The results of Csoergo-Révész increments are a special case,and it also implies the results of the increments of the two-parameter Wiener process. 展开更多
关键词 fractional Wiener process general form of increment.
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A time fractional model to represent rainfall process 被引量:1
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作者 Jacques GOLDER Maminirina JOELSON +1 位作者 Marie-Christine NEEL Liliana DI PIETRO 《Water Science and Engineering》 EI CAS CSCD 2014年第1期32-40,共9页
This paper deals with a stochastic representation of the rainfall process. The analysis of a rainfall time series shows that cumulative representation of a rainfall time series can be modeled as a non-Gaussian random ... This paper deals with a stochastic representation of the rainfall process. The analysis of a rainfall time series shows that cumulative representation of a rainfall time series can be modeled as a non-Gaussian random walk with a log-normal jump distribution and a time-waiting distribution following a tempered a-stable probability law. Based on the random walk model, a fractional Fokker-Planck equation (FFPE) with tempered a-stable waiting times was obtained. Through the comparison of observed data and simulated results from the random walk model and FFPE model with tempered a-stable waiting times, it can be concluded that the behavior of the rainfall process is globally reproduced, and the FFPE model with tempered a-stable waiting times is more efficient in reproducing the observed behavior. 展开更多
关键词 rainfall process heavy-tailed probability distribution tempered a-stable probability law log-normal law Hurst exponent continuous time random walk model fractional Fokker-Planck equation
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Design of Smith Predictor Based Fractional Controller for Higher Order Time Delay Process 被引量:1
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作者 P.R.Hemavathy Y.Mohamed Shuaib S.K.Lakshmanaprabu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第6期481-498,共18页
Normally all real world process in a process industry will have time delay.For those processes with time delays,obtaining satisfactory closed loop performances becomes very difficult.In this work,three interacting cyl... Normally all real world process in a process industry will have time delay.For those processes with time delays,obtaining satisfactory closed loop performances becomes very difficult.In this work,three interacting cylindrical tank process is considered for study and the objective of the work is to compensate for time delays using smith predictor structure and to maintain the level in the third tank.Input/Output data is generated for the three interacting tank process.It is approximated as Integer First Order Plus Dead Time system(IFOPDT)and Fractional First Order Plus Dead Time system(FFOPDT).Smith predictor based fractional order Proportional Integral controller and Integer order Proportional Integral controller is designed for the IFOPDT and FFOPDT model using frequency response technique and their closed loop performance indices are compared and tabulated.The servo and regulatory responses are simulated using Matlab/Simulink. 展开更多
关键词 fractional order proportional integral CONTROLLER frequency response technique SMITH PREDICTOR three INTERACTING tank process
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On Optimal Sparse-Control Problems Governed by Jump-Diffusion Processes 被引量:1
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作者 Beatrice Gaviraghi Andreas Schindele +1 位作者 Mario Annunziato Alfio Borzì 《Applied Mathematics》 2016年第16期1978-2004,共27页
A framework for the optimal sparse-control of the probability density function of a jump-diffusion process is presented. This framework is based on the partial integro-differential Fokker-Planck (FP) equation that gov... A framework for the optimal sparse-control of the probability density function of a jump-diffusion process is presented. This framework is based on the partial integro-differential Fokker-Planck (FP) equation that governs the time evolution of the probability density function of this process. In the stochastic process and, correspondingly, in the FP model the control function enters as a time-dependent coefficient. The objectives of the control are to minimize a discrete-in-time, resp. continuous-in-time, tracking functionals and its L2- and L1-costs, where the latter is considered to promote control sparsity. An efficient proximal scheme for solving these optimal control problems is considered. Results of numerical experiments are presented to validate the theoretical results and the computational effectiveness of the proposed control framework. 展开更多
关键词 jump-diffusion processes Partial Integro-Differential Fokker-Planck Equation Optimal Control Theory Nonsmooth Optimization Proximal Methods
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REMARKS ON SUB-FRACTIONAL BESSEL PROCESSES 被引量:1
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作者 申广君 陈超 闫理坦 《Acta Mathematica Scientia》 SCIE CSCD 2011年第5期1860-1876,共17页
Let S = {(St1,···,Std )}t≥0 denote a d-dimensional sub-fractional Brownian motion with index H ≥ 1/2. In this paper we study some properties of the process X of the formwhere Rt = ((St1)2+·... Let S = {(St1,···,Std )}t≥0 denote a d-dimensional sub-fractional Brownian motion with index H ≥ 1/2. In this paper we study some properties of the process X of the formwhere Rt = ((St1)2+···+(Std)2)~1/2 is the sub-fractional Bessel process. 展开更多
关键词 sub-fractional Brownian motion Malliavin calculus sub-fractional Bessel processes chaos expansion
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Existence and joint continuity of local time of multi-parameter fractional Lévy processes
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作者 林正炎 程宗毛 Xing-ming GUO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第3期381-390,共10页
In this paper, we introduce the definition of a multi-parameter fractional Lévy process and its local time, and show its decomposition. Using the decomposition, we prove existence and joint continuity of its loca... In this paper, we introduce the definition of a multi-parameter fractional Lévy process and its local time, and show its decomposition. Using the decomposition, we prove existence and joint continuity of its local time. 展开更多
关键词 multi-parameter fractional Lévy process fractional Brownian sheet local time Gaussian random field multi-parameter Poisson process multi-parameter Brownian motion
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THE JOINT DISTRIBUTIONS OF SOME ACTUARIAL DIAGNOSTICS FOR THE JUMP-DIFFUSION RISK PROCESS
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作者 吕玉华 吴荣 徐润 《Acta Mathematica Scientia》 SCIE CSCD 2010年第3期664-676,共13页
In this article, the joint distributions of several actuarial diagnostics which are important to insurers' running for the jump-diffusion risk process are examined. They include the ruin time, the time of the surplus... In this article, the joint distributions of several actuarial diagnostics which are important to insurers' running for the jump-diffusion risk process are examined. They include the ruin time, the time of the surplus process leaving zero ultimately (simply, the ultimately leaving-time), the surplus immediately prior to ruin, the supreme profits before ruin, the supreme profits and deficit until it leaves zero ultimately and so on. The explicit expressions for their distributions are obtained mainly by the various properties of Levy process, such as the homogeneous strong Markov property and the spatial homogeneity property etc, moveover, the many properties for Brownian motion. 展开更多
关键词 jump-diffusion risk process Brownian motion time of ruin ultimately leaving-time homogeneous strong Markov property
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Fractional Processing Based Adaptive Beamforming Algorithm
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作者 Syed Asghar Ali Shah Tariqullah Jan +3 位作者 Syed Muslim Shah Ruhul Amin Khalil Ahmad Sawalmeh Muhammad Anan 《Computers, Materials & Continua》 SCIE EI 2023年第7期1065-1084,共20页
Fractional order algorithms have shown promising results in various signal processing applications due to their ability to improve performance without significantly increasing complexity.The goal of this work is to in... Fractional order algorithms have shown promising results in various signal processing applications due to their ability to improve performance without significantly increasing complexity.The goal of this work is to inves-tigate the use of fractional order algorithm in the field of adaptive beam-forming,with a focus on improving performance while keeping complexity lower.The effectiveness of the algorithm will be studied and evaluated in this context.In this paper,a fractional order least mean square(FLMS)algorithm is proposed for adaptive beamforming in wireless applications for effective utilization of resources.This algorithm aims to improve upon existing beam-forming algorithms,which are inefficient in performance,by offering faster convergence,better accuracy,and comparable computational complexity.The FLMS algorithm uses fractional order gradient in addition to the standard ordered gradient in weight adaptation.The derivation of the algorithm is provided and supported by mathematical convergence analysis.Performance is evaluated through simulations using mean square error(MSE)minimization as a metric and compared with the standard LMS algorithm for various parameters.The results,obtained through Matlab simulations,show that the FLMS algorithm outperforms the standard LMS in terms of convergence speed,beampattern accuracy and scatter plots.FLMS outperforms LMS in terms of convergence speed by 34%.From this,it can be concluded that FLMS is a better candidate for adaptive beamforming and other signal processing applications. 展开更多
关键词 Adaptive beamforming adaptive array fractional processing least mean square fractional least mean square
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Optimal Control for Insurers with a Jump-diffusion Risk Process
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作者 吴锟 肖建武 罗荣华 《Chinese Quarterly Journal of Mathematics》 2015年第4期562-569,共8页
In this paper, the optimal XL-reinsurance of an insurer with jump-diffusion risk process is studied. With the assumptions that the risk process is a compound Possion process perturbed by a standard Brownian motion and... In this paper, the optimal XL-reinsurance of an insurer with jump-diffusion risk process is studied. With the assumptions that the risk process is a compound Possion process perturbed by a standard Brownian motion and the reinsurance premium is calculated according to the variance principle, the implicit expression of the priority and corresponding value function when the utility function is exponential are obtained. At last, the value function is argued, the properties of the priority about parameters are discussed and numerical results of the priority for various claim-size distributions are shown. 展开更多
关键词 HJB equation variance principle jump-diffusion process
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Integro-Differential Equations for a Jump-Diffusion Risk Process with Dependence between Claim Sizes and Claim Intervals
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作者 Heli Gao 《Journal of Applied Mathematics and Physics》 2016年第11期2061-2068,共8页
The classical Poisson risk model in ruin theory assumed that the interarrival times between two successive claims are mutually independent, and the claim sizes and claim intervals are also mutually independent. In thi... The classical Poisson risk model in ruin theory assumed that the interarrival times between two successive claims are mutually independent, and the claim sizes and claim intervals are also mutually independent. In this paper, we modify the classical Poisson risk model to describe the surplus process of an insurance portfolio. We consider a jump-diffusion risk process compounded by a geometric Brownian motion, and assume that the claim sizes and claim intervals are dependent. Using the properties of conditional expectation, we establish integro-differential equations for the Gerber-Shiu function and the ultimate ruin probability. 展开更多
关键词 jump-diffusion Risk process Diffusion Geometric Brownian Motion Gerber-Shiu Function
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Decomposition of Supercritical Linear-Fractional Branching Processes
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作者 Serik Sagitov Altynay Shaimerdenova 《Applied Mathematics》 2013年第2期352-359,共8页
It is well known that a supercritical single-type Bienayme-Galton-Watson process can be viewed as a decomposable branching process formed by two subtypes of particles: those having infinite line of descent and those w... It is well known that a supercritical single-type Bienayme-Galton-Watson process can be viewed as a decomposable branching process formed by two subtypes of particles: those having infinite line of descent and those who have finite number of descendants. In this paper we analyze such a decomposition for the linear-fractional Bienayme-Galton-Watson processes with countably many types. We find explicit expressions for the main characteristics of the reproduction laws for so-called skeleton and doomed particles. 展开更多
关键词 Harris-Sevastyanov Transformation Dual REPRODUCTION Law Branching process with Countably MANY Types Multivariate Linear-fractional Distribution Bienaymé-Galton-Watson process Conditioned Branching process
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Reservoir information extraction using a fractional Fourier transform and a smooth pseudo Wigner-Ville distribution 被引量:5
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作者 王祝文 王晓丽 +3 位作者 向旻 刘菁华 张雪昂 杨闯 《Applied Geophysics》 SCIE CSCD 2012年第4期391-400,494,495,共12页
Currently, it is difficult for people to express signal information simultaneously in the time and frequency domains when analyzing acoustic logging signals using a simple-time or frequency-domain method. It is diffic... Currently, it is difficult for people to express signal information simultaneously in the time and frequency domains when analyzing acoustic logging signals using a simple-time or frequency-domain method. It is difficult to use a single type of time-frequency analysis method, which affects the feasibility of acoustic logging signal analysis. In order to solve these problems, in this paper, a fractional Fourier transform and smooth pseudo Wigner Ville distribution (SPWD) were combined and used to analyze array acoustic logging signals. The time-frequency distribution of signals with the variation of orders of fractional Fourier transform was obtained, and the characteristics of the time-frequency distribution of different reservoirs under different orders were summarized. Because of the rotational characteristics of the fractional Fourier transform, the rotation speed of the cross terms was faster than those of primary waves, shear waves, Stoneley waves, and pseudo Rayleigh waves. By choosing different orders for different reservoirs according to the actual circumstances, the cross terms were separated from the four kinds of waves. In this manner, we could extract reservoir information by studying the characteristics of partial waves. Actual logging data showed that the method outlined in this paper greatly weakened cross-term interference and enhanced the ability to identify partial wave signals. 展开更多
关键词 fractional Fourier transform smooth pseudo Wigner-Ville distribution arrayacoustic logging signal processing RESERVOIRS
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