摘要:

In this paper, two models, based on the idea of urn models, for the spread of chlamydia in a closed population are presented. Difference equations are derived and analyzed for the expected number of infections in the population. The stability analysis of the difference equations is accomplished using techniques based on Lyapunov methods. There exist two equilibria, an endemic equilibrium and the trivial equibrium (infection-free). To reduce the level of infection, so that trivial equilibrium is approached, the basic reproductive rateR0, must be reduced to a level less than unity.

ISSN:1023-6198    

DOI:10.1080/10236199608808039

出版商:Gordon and Breach Science Publishers SA    

年代:1996

数据来源: Taylor

摘要:

This paper presents some sufficient conditions for the positive equilibrium in a recent model of flour beetle population growth due to B. Dennis et al (1994) to be asymptotically stable.

ISSN:1023-6198    

DOI:10.1080/10236199608808040

出版商:Gordon and Breach Science Publishers SA    

年代:1996

数据来源: Taylor

摘要:

In this Paper we generalize some recent results concerning sequences satisfying recursions essentially of the typewhereris a positive integernranges over the integers, and ∈ is equal to 1.0 or -1. By means of a map inRwhich keeps invariant certain surfaces, we study the dynamic of the solutions of such recursions and identity their periodicities.

ISSN:1023-6198    

DOI:10.1080/10236199608808041

出版商:Gordon and Breach Science Publishers SA    

年代:1996

数据来源: Taylor

摘要:

In 1992 Herbert Wilf and Doron Zeilberger showed how Sister Celine's technique could be used to establish thecertification procedurefor proper-hypergeometric summations in one variable. The basis of the procedure depends on showing thateveryproper-hypergeometric termFph(n, k) satisfied some nontrivialk-free recurrence.

ISSN:1023-6198    

DOI:10.1080/10236199608808042

出版商:Gordon and Breach Science Publishers SA    

年代:1996

数据来源: Taylor

摘要:

Ordinary differential equations of the formand theirp-th order one-step discretization approximations of classare considered. On intervals of lengthT, the time-h-map of the induced solution flow is compared to the discrete-time dynamical system obtained via discretization. For stepsizehsufficiently small, theirCj- distance is proved (see Theorem 1.1) to be less than const1(T).where, with some constant γ not much greater (sometimes even strictly smaller) thanis basically exp((j+1)γT),j=0,1,…,p+k. The proof is based on a Pascal triangle property (see Inequality (33)) of higher order chain rule folmulas. Applications to the numerics of global stable/unstable manifolds of hyperbolic equilibria are given.

ISSN:1023-6198    

DOI:10.1080/10236199608808043

出版商:Gordon and Breach Science Publishers SA    

年代:1996

数据来源: Taylor

摘要:

Usung a Liapunov-Razumikhin type function, we find conditions under which the zero solution of an autonomous delay difference equation is globally asymptoticallly stable. Our results are applied to discrete logistic equation with mulitidelays and to a model in population dynamics.

ISSN:1023-6198    

DOI:10.1080/10236199608808044

出版商:Gordon and Breach Science Publishers SA    

年代:1996

数据来源: Taylor

摘要:

In this section we present some open problems and conjectures about some interesting types of difference equations. Please submit your problems and conjecutures with all relevant informations to G. Ladas

ISSN:1023-6198    

DOI:10.1080/10236199608808045

出版商:Gordon and Breach Science Publishers SA    

年代:1996

数据来源: Taylor

ISSN:1023-6198    

DOI:10.1080/10236199608808038

出版商:Gordon and Breach Science Publishers SA    

年代:1996

数据来源: Taylor