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Chinese Annals of mathematics,Series B 2024年第4期45卷 537-554页

作者： Shuangrong LI Wancheng SHENG department of mathematics Shanghai UniversityShanghai 200444China department of mathematics Zhejiang University of Science and TechnologyHangzhou 310023China Corresponding author.department of mathematics Newtouch Center for Mathematics of Shanghai UniversityShanghai UniversityShanghai 200444China

In this paper,the authors study the centered waves for the two-dimensional(2D for short)pseudo-steady supersonic flow with van der Waals gas satisfied Maxwell's law around a sharp *** view of the initial value of the specific volume and the properties of van der Waals gas,the centered waves at the sharp corner are constructed by *** is shown that the supersonic incoming flow turns the sharp corner by a centered simple wave or a centered simple wave with right-contact discontinuity or a composite wave(jump-fan,fan-jump or fan-jump-fan),or a combination of waves and constant ***,the critical angle of the sharp corner corresponding to the appearance of the vacuum phenomenon is obtained.

关键词： Two-dimensional Euler equations Van der Waals gas Centered simple wave Composite wave

Critical observability of partially observed discrete event systems under cyber attacks

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science China(Information sciences) 2024年第2期67卷 333-334页

作者： Liyun TONG Jinling LIANG Yang LIU department of mathematics School of SciencesHangzhou Dianzi University School of mathematics Southeast University College of mathematics and computer science Zhejiang Normal University

The discrete event system(DES) is a dynamic system driven by asynchronous/sudden events and has been widely used in many critical infrastructures, such as electric transportation networks and intelligent transportatio...

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Global Spherically Symmetric Solutions for a Coupled Compressible Navier–Stokes/Allen–Cahn System

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Acta Mathematica Sinica,English Series 2024年第8期40卷 2037-2064页

作者： Chang Ming SONG Jian Lin ZHANG Yuan Yuan WANG department of Applied mathematics School of Mathematics and Information ScienceZhongyuan University of TechnologyZhengzhou 450007P.R.China

In this paper,we consider the global spherically symmetric solutions for the initial boundary value problem of a coupled compressible Navier–Stokes/Allen–Cahn system which describes the motion of two-phase viscous compressible *** prove the existence and uniqueness of global classical solution,weak solution and strong solution under the assumption of spherically symmetry condition for initial dataρ0 without vacuum state.

关键词： Diffuse interface model global solutions Navier-Stokes equations Allen-Cahn equation spherically symmetry

Energy exchange between charged relativistic fluids in f(T) gravity

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Communications in Theoretical Physics 2024年第10期76卷 108-120页

作者： Z Yousaf U A Khokhar Nasser Bin Turki T Suzuki department of mathematics University of the Punjab Quaid-i-Azam Campus department of mathematics College of Science King Saud University department of Regional Management Faculty of Management Fukushima College

This study focuses on the effects of a polytropic fluid on a charged gravitational source within f(T) gravity, where T is the torsion scalar. We investigate how the electromagnetic field affects the flow of energy in spherically symmetric and static celestial objects that contain relativistic fluids. By using the gravitational decoupling technique, we analyze the effects of polytropic fluid on the dynamics of the gravitational source, accompanied by the matching of the interior geometry with an exterior at the hypersurface Σ. Finally, with the help of the Tolman ⅡV solution, we observe the conduct of energy conditions with the existence of charge using f(T)field equations and got the intended outcomes.

关键词： anisotropy complexity energy exchange hydrodynamics self-gravitating systems

On thermoelastic problem based on four theories with the efficiency of the magnetic field and gravity

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Journal of Ocean Engineering and science 2024年第4期9卷 338-347页

作者： A.A.Kilany A.N.Abd-alla A.M.Abd-Alla S.M.Abo-Dahab department of mathematics Faculty of ScienceSohag UniversitySohag 82524 Egypt department of computer science Faculty of Computers and InformationLuxor UniversityEgypt department of mathematics Faculty of ScienceSouth Valley UniversityQena 83523Egypt

The fundamental objective of this paper is to study the effectiveness of magnetic field and gravity on an isotropic homogeneous thermoelastic structure based on four theories of generalized *** another meaning,the models of coupled dynamic theory(CDT),Lord-Shulman(LS),Green-Lindsay(GL)as well as Green-Naghdi(GN II)will be taken in the ***,applying the harmonic method(normal mode technique),the solution of the governing equations and the expressions for the components of the displacement,temperature and(Mechanical and Maxwell’s)stresses is taken into account and calculated *** impacts of the gravity and magnetic field are illustrated graphically which are pronounced on the different physical ***,the results of some research that others have previously obtained may be found some or all of them as special cases from this study.

关键词： Generalized thermoelasticity Gravity Magnetic field Green and Naghdi TheoryⅡ Normal mode approach

EPR-Net: constructing a non-equilibrium potential landscape via a variational force projection formulation

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National science Review 2024年第7期11卷 135-147页

作者： Yue Zhao Wei Zhang Tiejun Li Center for Data science Peking University Zuse Institute Berlin department of mathematics and computer science Freie Universit?t Berlin Laboratory of mathematics and Applied mathematics(LMAM)and School of Mathematical sciences Peking University Center for Machine Learning Research Peking University

We present EPR-Net, a novel and effective deep learning approach that tackles a crucial challenge in biophysics: constructing potential landscapes for high-dimensional non-equilibrium steady-state ***-Net leverages a nice mathematical fact that the desired negative potential gradient is simply the orthogonal projection of the driving force of the underlying dynamics in a weighted inner-product ***, our loss function has an intimate connection with the steady entropy production rate(EPR),enabling simultaneous landscape construction and EPR estimation. We introduce an enhanced learning strategy for systems with small noise, and extend our framework to include dimensionality reduction and the state-dependent diffusion coefficient case in a unified fashion. Comparative evaluations on benchmark problems demonstrate the superior accuracy, effectiveness and robustness of EPR-Net compared to existing methods. We apply our approach to challenging biophysical problems, such as an eight-dimensional(8D)limit cycle and a 52D multi-stability problem, which provide accurate solutions and interesting insights on constructed landscapes. With its versatility and power, EPR-Net offers a promising solution for diverse landscape construction problems in biophysics.

关键词： high-dimensional potential landscape non-equilibrium system entropy production rate dimensionality reduction deep learning

Casson hybrid nanofluid flow over a Riga plate for drug deliveryapplications with double diffusion

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Chinese Physics B 2024年第10期33卷 311-320页

作者： Abeer S.Alnahdi Taza Gul department of mathematics and Statistics Faculty of ScienceImam Mohammad Ibn Saud Islamic University(IMSIU)RiyadhSaudi Arabia department of mathematics City University of Science and Information Technology25000PeshawarPakistan DGoST-Directorate General of science&Technology Khyber PakhtunkhwaPeshawarPakistan

Casson fluid-mediated hybrid nanofluids are more effective at transferring heat than traditional heat transfer fluids in terms of thermal *** exchangers,cooling systems and other thermal management systems are ideal for use with Casson *** control of the flow and release of medication is necessary when using Casson fluids in drug delivery systems because of their unique rheological *** involves the creation of nanoparticles that are loaded with drugs and distributed in Casson fluid-based carriers for targeted *** this study,to create a hybrid nanofluid,both single-walled carbon nanotubes(SWCNTs)and multi-walled carbon nanotubes(MWCNTs)are dispersed in a Casson fluid with Fourier’s and Fick’s laws *** Casson fluid is suitable for various engineering and medical applications due to the enhancement of heat transfer and thermal conductivity by the carbon *** objective is to understand how SWCNTs and MWCNTs impact the flow field by studying the flow behavior of the Casson hybrid nanofluid when it is stretched against a Riga *** Darcy-Forchheimer model is also used to account for the impact of the porous medium near the stretching *** linear and quadratic drag terms are taken into account in this model to accurately predict the flow behavior of the *** addition,the homotopy analysis method is utilized to address the model *** outcomes are discussed and deliberated based on drug delivery *** findings shed valuable light on the flow characteristics of a Casson hybrid nanofluid comprising SWCNTs and *** is observed that the incorporation of carbon nanotubes makes the nanofluid a promising candidate for medical applications due to its improved heat transfer properties.

关键词： carbon nanotubes(CNTs) Riga plate Casson fluid with Fourier’s and Fick’s laws analytical solutions

Magneto-Photo-Thermoelastic Excitation Rotating Semiconductor Medium Based on Moisture Diffusivity

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computer Modeling in Engineering & sciences 2024年第10期141卷 107-126页

作者： Khaled Lotfy A.M.S.Mahdy Alaa A.El-Bary E.S.Elidy department of mathematics Faculty of ScienceZagazig UniversityZagazig44519Egypt department of mathematics Faculty of ScienceTaibah UniversityMadinah42353Saudi Arabia department of mathematics and Statistics College of ScienceTaif UniversityTaif11099Saudi Arabia Arab Academy for science Technology and Maritime TransportAlexandria1029Egypt

In this research,we focus on the free-surface deformation of a one-dimensional elastic semiconductor medium as a function of magnetic field and moisture *** problem aims to analyze the interconnection between plasma and moisture diffusivity processes,as well as thermo-elastic *** study examines the photothermoelasticity transport process while considering the impact of moisture *** employing Laplace’s transformation technique,we derive the governing equations of the photo-thermo-elastic *** equations include the equations for carrier density,elastic waves,moisture transport,heat conduction,and constitutive *** stresses,thermal conditions,and plasma boundary conditions are used to calculate the fundamental physical parameters in the Laplace *** employing numerical techniques,the Laplace transform is inverted to get complete time-domain solutions for the primary physical domains under ***,thermoelastic,and thermoelectric characteristics are employed in conjunction with a graphical analysis that takes into consideration the effects of applied forces on displacement,moisture concentration,carrier density,stress due to forces,and temperature distribution.

关键词： Moisture diffusivity semiconductor photothermoelastic rotation thermomechanical waves laplace transform

Severe acute respiratory syndrome-coronavirus-2(SARS-COV-2)infection of pneumocytes with vaccination and drug therapy:Mathematical analysis and optimal control

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International Journal of Biomathematics 2024年第2期17卷 299-334页

作者： R.Viriyapong P.Inkhao department of mathematics Faculty of Science Naresuan University Phitsanulok65000Thailand

We propose a mathematical model studying a within-host infection dynamics of SARSCoV-2 in *** model incorporates immune response,vaccination and antiviral *** crucial properties of the model-the existence,positivity and boundary of solutions are *** points and the basic reproduction number are *** stability of each equilibrium point is *** control is applied to the model by adding three control variables:vaccination,treatment by Favipiravir and treatment by *** results show that each individual control could reduce SARS-CoV-2 infection in some aspects;however,with a combination of three controls,we obtain the best results in reducing SARS-CoV-2 *** study has emphasized the importance of prevention by vaccine and the antiviral treatments.

关键词： SARS-CoV-2 vaccination drug therapy immune response optimal control

A Minimum Residual Based Gradient Iterative Method for a Class of Matrix Equations

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 17-34页

作者： Qing-qing Zheng department of mathematics College of ScienceChina University of Petroleum-BeijingBeijing102249China

In this paper, we present a minimum residual based gradient iterative method for solving a class of matrix equations including Sylvester matrix equations and general coupled matrix equations. The iterative method uses a negative gradient as steepest direction and seeks for an optimal step size to minimize the residual norm of next iterate. It is shown that the iterative sequence converges unconditionally to the exact solution for any initial guess and that the norm of the residual matrix and error matrix decrease monotonically. Numerical tests are presented to show the efficiency of the proposed method and confirm the theoretical results.

关键词： Sylvester matrix equation coupled matrix equation minimum residual gradient descent convergence analysis