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Journal of Systems Science and Systems Engineering 2024年第2期33卷 187-206页

作者： Mintu Kumar Himani Pant S.B.Singh department of {1. statistics and Computer Science G.B.Pant University of AgricultureTechnologyPantnagarUttarakhandIndia

Uncertainty is an important factor that needs to be considered while analyzing the performance of any engineering *** order to quantify uncertainty,fuzzy set theory is frequently used by most of researchers,including energy system *** to the classical reliability theory,component lifetimes have crisp parameters,but due to uncertainty and inaccuracy in data,it is sometimes very difficult to determine the exact values of these parameters in real-world *** overcome this difficulty in the current research,failure and repair rates were taken as triangular fuzzy numbers to determine the fuzzy availability of a system undergoing calendar-based periodic inspection subject to multiple failure modes(FMs).It was assumed that each component in the system had an exponential failure rate and repair rate with fuzzy *** FMs were explicitly taken into account when a functional state of the system was *** FM had a random failure *** the occurrence of any failure,a random time was selected for the relevant corrective repair *** proposed research was studied for one of the major sources of green energy,namely a wind turbine system wherein all the derived propositions have been implemented on it.

关键词： Fuzzy reliability fuzzy availability wind turbine system multiple failure modes triangular fuzzy number

LOW-REGULARITY SOLUTIONS TO FOKKER-PLANCK-TYPE SYSTEMS IN THE WHOLE SPACE

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Acta Mathematica Scientia 2024年第6期44卷 2361-2390页

作者：谈丽华樊迎哲 School of mathematics and {1. Hubei University of Education School of mathematics and {1. Nanyang Normal University

In this manuscript,we consider two kinds of the Fokker-Planck-type systems in the whole *** first part involves proving the global existence and the algebraic time decay rates of the mild solutions to the Fokker-Planck-Boltzmann equation near Maxwellians if initial data satisfies some smallness in the function space Lk1.T∞Lv2∩LkpLT∞*** second part proves the global existence of the mild solutions to the Vlasov-Poisson-Fokker-Planck system in the function space Lk1.T∞Lv2,and we also obtain the exponential time decay rates,which are different from the algebraic time decay rates of the Fokker-Planck-Boltzmann *** analysis is based on Lk1.T∞Lv2function space introduced by Duan et al.（Comm Pure Appl Math,2021.74:932-1.20）,the Lk1.Lkpapproach developed by Duan et al.（SIAM J Math Anal,2024,56:762-800）,and the coercivity property of the Fokker-Planck ***,it is worth pointing out that the Lk1.Lkpapproach is not required for the VlasovPoisson-Fokker-Planck system,due to the influence of the electric field term,which is different from the Fokker-Planck-Boltzmann equation in this paper and in the work of Duan et al.（SIAM J Math Anal,2024,56:762-800）.

关键词： 35A05 35L45 algebraic time decay rates exponential time decay rates global existence low regularity space the whole space

A Novel Iterative Method to Find theMoore-Penrose Inverse of a Tensor with Einstein Product

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Numerical mathematics(Theory,Methods and Applications) 2024年第1期17卷 37-68页

作者： Raziyeh Erfanifar Masoud Hajarian Khosro Sayevand department of Applied {1. Faculty of Mathematical SciencesShahid Beheshti UniversityTehranIran Faculty of mathematics and {1. Malayer UniversityMalayerIran

In this study,based on an iterative method to solve nonlinear equations,a third-order convergent iterative method to compute the Moore-Penrose inverse of a tensor with the Einstein product is presented and *** compar-isons of the proposed method with other methods show that the average number of iterations,number of the Einstein products,and CPU time of our method are considerably less than other *** some applications,partial and fractional differential equations that lead to sparse matrices are considered as *** use the iterates obtained by the method as a preconditioner,based on tensor form to solve the multilinear system A∗N X=***,several practical numerical examples are also given to display the accuracy and efﬁciency of the new *** presented results show that the proposed method is very robust for obtaining the Moore-Penrose inverse of tensors.

关键词： Tensor iterative methods Moore-Penrose inverse Einstein product

Non-static plane symmetric perfect fluid solutions and Killing symmetries in f(R,T)gravity

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Communications in Theoretical Physics 2024年第2期76卷 145-150页

作者： Preeti Dalal Karanjeet Singh Sachin Kumar department of {1. and statistics Central University of PunjabBathinda151401PunjabIndia department of {1. Jaypee University of Information TechnologySolan173234Himachal PradeshIndia

In this paper,the non-static solutions for perfect fluid distribution with plane symmetry in f(R,T)gravitational theory are ***,using the Lie symmetries,symmetry reductions are performed for considered vector fields to reduce the number of independent ***,corresponding to each reduction,exact solutions are *** vectors lead to different conserved ***,we figure out the Killing vector fields corresponding to all derived *** derived solutions are further studied and it is observed that all of the obtained spacetimes,at least admit to the minimal symmetry group which consists of δ_(y),δ_(z) and -zδ_(y)+yδ_(z).The obtained metrics,admit to 3,4,6,and 1.,Killing vector *** of linear momentum in the direction of y and z,and angular momentum along the x axis is provided by all derived solutions.

关键词： Einstein field equations perfect fluid solutions f(R T)gravity killing symmetries

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Influence of Brownian Motion, Thermophoresis and Magnetic Effects on a Fluid Containing Nanoparticles Flowing over a Stretchable Cylinder

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Fluid Dynamics & Materials Processing 2024年第3期20卷 525-536页

作者： Aaqib Majeed Ahmad Zeeshan department of {1. The University of FaisalabadFaisalabad38000Pakistan department of {1. and statistics FBASInternational Islamic University IslamabadIslamabad44000Pakistan

The influence of Brownian motion and thermophoresis on a fluid containing nanoparticles flowing over a stretchable cylinder is *** classical Navier-Stokes equations are considered in a porous *** addition,the Lorentz force is taken into *** controlling coupled nonlinear partial differential equations are transformed into a system of first order ordinary differential equations by means of a similarity *** resulting system of equations is solved by employing a shooting approach properly implemented in *** evolution of the boundary layer and the growing velocity is shown graphically together with the related profiles of concentration and *** magnetic field has a different influence(in terms of trends)on velocity and concentration.

关键词： Mixed convection Brownian motion heat transfer porous surface velocity slip

On optimal control at the onset of a new viral outbreak

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Infectious Disease Modelling 2024年第4期9卷 995-1006页

作者： Alexandra Smirnova Xiaojing Ye department of {1.&statistics Georgia State UniversityAtlantaUSA

We propose a versatile model with a flexible choice of control for an early-pandemic outbreak prevention when vaccine/drug is not yet *** that stage,control is often limited to non-medical interventions like social distancing and other behavioral *** the SIR optimal control problem,we show that the running cost of control satisfying mild,practically justified conditions generates an optimal strategy,u(t),t∈[0,T],that is sustainable up until some moment τ∈[0,T).However,for any t∈[τ,T],the function u(t)will decline as t approaches T,which may cause the number of newly infected people to ***,the window from 0 to τ is the time for public health officials to prepare alternative mitigation measures,such as vaccines,testing,antiviral medications,and *** addition to theoretical study,we develop a fast and stable computational method for solving the proposed optimal control *** efficiency of the new method is illustrated with numerical examples of optimal control trajectories for various cost functions and *** results provide a comprehensive demonstration of the effects of control on the epidemic spread and mitigation expenses,which can serve as invaluable references for public health officials.

关键词： Epidemiology Compartmental model Transmission dynamic Optimal control

Explicit solutions to the time-fractional generalized dissipative Kawahara equation

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Journal of Ocean Engineering and Science 2024年第4期9卷 348-352页

作者： Marwan Alquran Mohammed Ali Omar Alshboul department of {1. and statistics Jordan University of Science and TechnologyIrbid 22110Jordan

In this paper,the generalized dissipative Kawahara equation in the sense of conformable fractional derivative is presented and solved by applying the tanh-coth-expansion and sine-cosine function *** quadratic-case and cubic-case are investigated for the proposed *** solutions are obtained with highlighting to the effect of the presence of the alternative fractional-derivative and the effect of the added dissipation term to the generalized Kawahara *** graphical analysis is presented to support the findings of the ***,we believe that the obtained results in this work will be important and valuable in nonlinear sciences and ocean engineering.

关键词： Time-fractional Kawahara equation Conformable-derivative Tanh-coth-expansion method Sine-cosine function method

Reconstruction of incidence reporting rate for SARS-CoV-2 Delta variant of COVID-1. pandemic in the US

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Infectious Disease Modelling 2024年第1期9卷 70-83页

作者： Alexandra Smirnova Mona Baroonian department of {1.&statistics Georgia State UniversityAtlantaUSA

In recent years,advanced regularization techniques have emerged as a powerful tool aimed at stable estimation of infectious disease parameters that are crucial for future projections,prevention,and *** other system parameters,i.e.,incubation and recovery rates,the case reporting rate,Ψ,and the time-dependent effective reproduction number,R_(e)t,are directly influenced by a large number of factors making it impossible to pre-estimate these parameters in any meaningful *** this study,we propose a novel iteratively-regularized trust-region optimization algorithm,combined with SuSvIuIvRD compartmental model,for stable reconstruction ofΨand R_(e)t from reported epidemic data on vaccination percentages,incidence cases,and daily *** innovative regularization procedure exploits(and takes full advantage of)a unique structure of the Jacobian and Hessian approximation for the nonlinear observation *** proposed inversion method is thoroughly tested with synthetic and real SARS-CoV-2 Delta variant data for different regions in the United States of America from July 9,2021.to November 25,*** study shows that case reporting rate during the Delta wave of COVID-1. pandemic in the US is between 1.%and 37%,with most states being in the range from 1.%to 25%.This confirms earlier accounts on considerable under-reporting of COVID-1. cases due to the impact of”silent spreaders”and the limitations of testing.

关键词： Epidemiology Incidence reporting rate Compartmental model Transmission dynamic Regularization algorithm

Exponential-Poisson Parameters Estimation in Moving Extremes Ranked Set Sampling Design

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Acta Mathematicae Applicatae Sinica 2024年

作者： Meng CHEN Wang-xue CHEN Rui YANG Ya-wen ZHOU department of {1. and statistics Jishou University

In this article, the maximum likelihood estimators (MLEs) of the scale and shape parameters βandλfrom the Exponential-Poisson distribution will be considered in moving extremes ranked set sampling(MERSS). These MLEs will be compared in terms of asymptotic efficiencies. The numerical results show that these MLEs in MERSS can be real competitors against those in simple random sampling.

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Reliability of a Multicomponent Stress-strength Model Based on a Bivariate Kumaraswamy Distribution with Censored Data

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 478-507页

作者： Cong-hua CHENG School of mathematics and {1. Zhaoqing UniversityZhaoqing 526061China

In this paper,we consider a system which has k statistically independent and identically distributed strength components and each component is constructed by a pair of statistically dependent elements with doubly type-II censored *** elements(X1.Y1.,(X2,Y2),…,(Xk,Yk)follow a bivariate Kumaraswamy distribution and each element is exposed to a common random stress T which follows a Kumaraswamy *** system is regarded as operating only if at least s out of k(1.s≤k)strength variables exceed the random *** multicomponent reliability of the system is given by Rs,k=P(at least s of the(Z1.…,Zk)exceed T)where Zi=min(Xi,Yi),i=1.…,*** Bayes estimates of Rs,k have been developed by using the Markov Chain Monte Carlo methods due to the lack of explicit *** uniformly minimum variance unbiased and exact Bayes estimates of Rs,k are obtained analytically when the common second shape parameter is *** asymptotic confidence interval and the highest probability density credible interval are constructed for Rs,*** reliability estimators are compared by using the estimated risks through Monte Carlo simulations.

关键词： stress-strength model bivariate Kumaraswamy distribution multicomponent reliability doubly Type-II censored scheme interval estimation

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