检索结果-南通市图书馆

Dynamic analysis of a fractional order system

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Biomathematics 2015年第6期8卷 157-173页

作者： M. Javidi N. Nyamoradi faculty of mathematical sciencesuniversity of tabriz Tabriz Iran Department of Mathematics Faculty of Sciences Razi University 67149 Kermanshah Iran

In this paper, we investigate the dynamical behavior of a fractional order phytoplankton- zooplankton system. In this paper, stability analysis of the phytoplankton zooplankton model （PZM） is studied by using the fractional Routh-Hurwitz stability conditions. We have studied the local stability of the equilibrium points of PZM. We applied an efficient numerical method based on converting the fractional derivative to integer derivative to solve the PZM.

关键词： Phytoplankton-zooplankton model Routh-Hurwitz stability conditions numerical simulation.

A fractional-order toxin producing phytoplankton and zooplankton system

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Biomathematics 2014年第4期7卷 63-83页

作者： M. Javidi N. Nyamoradi faculty of mathematical sciencesuniversity of tabriz Tabriz Iran Department of Mathematicsfaculty of Sciences Razi University 67149 Kermanshah Iran

In this work, we investigate the dynamical behavior of a fractional-order toxin producing on a phytoplankton-zooplankton （TPPZ） system with nutrient cycling. We propose a mathematical system to model this situation. All the feasible equilibria of the system are obtained and the conditions for the existence of the equilibriums are determined. Local stability analysis of the TPPZ is studied by using the fractional Routh-Hurwitz stability conditions. Numerical simulations are carried out for a hypothetical set of parameter values to substantiate our analytical findings.

关键词： Toxic-phytoplankton zooplankton stability numerical simulation frac-tional-order.

Optimal control of a fractional-order model for the HIV/AIDS epidemic

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Biomathematics 2018年第7期11卷 59-81页

作者： Hossein Kheiri Mohsen Jafari faculty of mathematical Sciences University of tabriz TabrizIran

In this paper,we present a general formulation for a fractional optimal control problem (FOCP),in which the state and co-state equations are given in terms of the left fractional *** develop the forward-backward sweep method (FBSM)using the Adamstype predictor-corrector method to solve the *** present a fractional model for transmission dynamics of human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS)with treatment and incorporate three control efforts (effective use of condoms,ART treatment and behavioral change control)into the model aimed at controlling the spread of HIV/AIDS *** necessary conditions for fractional optimal control of the disease are derived and *** numerical results show that implementing all the control efforts increases the life time and the quality of life those living with HIV and decreases significantly the number of HIV-infected and AIDS ***,the maximum levels of the controls and the value of objective functional decrease when the derivative order a limits to 1(0.7≤a <1).In addition,the effect of the fractional derivative order a (0.7≤a <1)on the spread of HIV/AIDS epidemic and the treatment of HIV-infected population is *** results show that the derivative order a can play the role of using ART treatment in the model.

关键词： Fractional optimal control diseases modeling numerical simulation HIV/AIDS dynamics

Global stability and optim al control of a two-patch tuberculosis epidemic model using fractional-order derivatives

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Biomathematics 2020年第3期13卷 1-27页

作者： Hossein Kheiri Mohsen Jafari faculty of mathematical Sciences University of tabriz TabrizIran

In this paper,we propose a fractional-order and two-patch model of tuberculosis(TB)epidemic,in which susceptible,slow latent,fast latent and infectious individuals can travel freely between the patches,but not under treatment infected individuals,due to medical *** obtain the basic reproduction number Ro for the model and extend the classical LaSalle's invariance principle for fractional differential *** show that if R0l,we obtain sufficient conditions under which the endernic equilibrium is unique and globally asymptotically *** extend the model by inclusion the time-dependent controls(effective treatment controls in both patches and controls of screening on travel of infectious individuals between patches),and formulate a fractional optimal control problem to reduce the spread of the *** numerical results show that the use of all controls has the most impact on disease control,and decreases the size of all infected compartments,but increases the size of susceptible compartment in both ***,also,investigate the impact of the fractional derivative order a on the values of the controls(0.7≤α≤1).The results show that the maximum levels of effective treatment controls in both patches increase when a is reduced from l,while the maximum level of the travel screening control of infectious individuals from patch 2 to patch 1 increases when o limits to 1.

关键词： Patch models fractional optimal control global stability tuberculosis epidemic

Backward bifurcation in a fractional-order and two-patch model of tuberculosis epidemic with incomplete treatment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Biomathematics 2021年第2期14卷 139-167页

作者： Mohsen Jafari Hossein Kheiri Azizeh Jabbari faculty of mathematical Sciences University of TabrizTabrizIran Marand faculty of Engineering University of TabrizTabrizIran

In this paper,we consider a tuberculosis model with incomplete treatment and extend the model to a Caputo fractional-order and two-patch version with exogenous re-infection among the treated individuals,in which only susceptible individuals can travel freely between the *** model has multiple *** determine conditions that lead to the appearance of a backward *** results show that the TB model can have exogenous reinfection among the treated individuals and,at the same time,does not exhibit backward ***,conditions that lead to the global asymptotic stability of the disease-free equilibrium are *** case without reinfection,the model has four *** this case,the global asymptotic stability of the equilibria is established using the Lyapunov function theory together with the LaSalle invariance principle for fractional differential equations(FDEs).Numerical simulations confirm the validity of the theoretical results.

关键词： Patch models fractional-order derivatives global stability backward bifurcation.

Dynamics of SVEIS epidemic model with distinct incidence

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Biomathematics 2015年第6期8卷 99-117页

作者： N. Nyamoradi M. Javidi B. Ahmad Department of Mathematics Faculty of Sciences Razi University 67149 Kermanshah Iran faculty of mathematical sciencesuniversity of tabriz Tabriz Iran Department of Mathematics Faculty of Science King Abdulaziz University P. O. Box 80203 Yeddah 21589 Saudi Arabia

In this paper, we study the global dynamics of a SVEIS epidemic model with distinct incidence for exposed and infectives. The model is analyzed for stability and bifurcation behavior. To account for the realistic phenomenon of non-homogeneous mixing, the effect of diffusion on different population subclasses is considered. The diffusive model is analyzed using matrix stability theory and conditions for Turing bifurcation are derived. Numerical simulations support our analytical results on the dynamic behavior of tile model.

关键词： SVEIS epidemic model diffusion Turing bifurcation stability basic repro-duction number numerical simulation.

PRODUCTS OF RESOLVENTS AND MULTIVALUED HYBRID MAPPINGS IN C AT(0) SPACES

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2018年第3期38卷 791-804页

作者： Gholamreza ZAMANI ESKANDANI Soheila AZARMI Masoumeh RAEISI Department of Pure Mathematics faculty of mathematical Sciences University of tabriz Department of Pure Mathematics Faculty of Mathematical SciencesUniversity of Tabriz

In this article, we introduce and investigate the concept of multivalued hybrid mappings in C AT（0） spaces by using the concept of quasilinearization. Also, we present a new iterative algorithm involving products of Moreau-Yosida resolvents for finding a common element of the set of minimizers of a finite family of convex functions and a common fixed point of two multivalued hybrid mappings in C AT（0） spaces.

关键词： Multivalued hybrid mappings convex optimization C AT(0) spaces

A mathematical analysis of a tuberculosis epidemic model with two treatments and exogenous re-infection

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

International Journal of Biomathematics 2020年第8期13卷 205-231页

作者： Mehdi Lotfi Azizeh Jabbarit Hossein Kheiri Department of Applied Mathematics faculty of mathematical Sciences University of tabriz TabrizIran Marand faculty of Engineering University of tabriz TabrizIran

In this paper,we propose a mathematical model of tuberculosis with two treatments and exogenous re-infection,in which the treatment is effective for number of infectious individuals and it fails for some other infectious individuals who are being *** show that the model exhibits the phenomenon of backward bifurcation,where a stable disease-free equilibrium coexists with a stable endemic equilibria when the related basic reproduction number is less than ***,it is shown that under certain conditions the model cannot exhibit backward ***,it is shown in the absence of re-infection,the backward bifurcation phenomenon does not exist,in which the disease-free equilibrium of the model is globally asymptotically stable when the associated reproduction number is less than *** global asymptotic stability of the endemic equilibrium,when the associated reproduction number is greater than unity,is established using the geometric *** simulations are presented to illustrate our main results.

关键词： Tuberculosis backward bifurcation geometric approach basic reproduction number stability analysis

Application of G′/G-expansion Method to Kuramoto-Sivashinsky Equation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2016年第3期32卷 623-630页

作者： Ghodrat Ebadi Anjan Biswas faculty of mathematical Sciences University of Tabriz Department of mathematical Sciences Delaware State University faculty of Science Department of MathematicsKing Abdulaziz University

This paper obtains the solutions of the Kuramoto-Sivashinsky equation. The G′/G method is used to carry out the integration of this equation. Subsequently, its special case, will be integrated and topological 1- soliton solution will be obtained by the soliton ansatz method. The restrictions on the parameters and exponents are also identified.

关键词： evolution equations solitons integrability