二階非線性差分、微分方程的定性分析.pdf

1、寧波大學(xué)碩士學(xué)位論文二階非線性差分、微分方程的定性分析姓名：曾春花申請學(xué)位級別：碩士專業(yè)：基礎(chǔ)數(shù)學(xué)指導(dǎo)教師：張建勛20070415P%R???Q4SQualitativeanalysisofseconddernonlineardifferenceequationsdifferentialequationsAbstractInthispaperwestudyinvariantintervalstheglobalasymptoticstab

2、ilitytheoscillationofthepositivesolutionoftheseconddernonlineardifferenceequationyn1=aynbyn?1yndiscussinvariantintervalstheglobalasymptoticstabilityofthepositivesolutionofthethesecondderrationaldifferenceequationxn1=αβxn

3、γxn?1ABxnCxn?1whereparametersabABCαβγ0C≥B.Inadditionweconsidertheseconddernonlineardifferentialequation(Gompertzmodelexistingreserveareawithdelay)???dxdt=rxln(Kx(t?τ))?σ1xσ2y?QExdydt=syln(Ly(t?τ))σ1x?σ2y???dxdt=rxln(Kx)?

4、σ1xσ2y(t?τ)?QExdydt=syln(Ly)σ1x(t?τ)?σ2ydiscussthecombinedeffectsofharvestingtimedelayonthesemodels.weobtaintheglobalasymptoticstabilitythesufficientnecessaryconditionftheexistenceofthepositivesolutiontheoptimalharvestin

5、gpolicywithoutdelayotherwisesomesufficientconditionswhichensurethestabilityofthepositivesolutionwithdelayareprovidedwhereparametersrsQσ1σ2KLτ00≤E≤Emax.Keywds:differenceequationinvariantintervalslocalasymptoticstablegloba