大连理工大学学报
大連理工大學學報
대련리공대학학보
JOURNAL OF DALIAN UNIVERSITY OF TECHNOLOGY
2010年
2期
304-308
,共5页
阶段结构%时滞%平衡点
階段結構%時滯%平衡點
계단결구%시체%평형점
stage-structured%delay%equilibrium point
研究了一个具有阶段结构和时滞的幼年染病单种群模型.通过常微分方程的特征根法,借助几何图形分析了3个平衡点的存在性,得到了它们局部稳定的充要条件.并且在推论中找到了参数τ影响平衡点稳定性的阈值,得到了当参数τ在不同区间取值时对应的平衡点的稳定性,并通过例题验证了定理的结论.最后,对于所得的数学结果给出了生物意义下的解释:若时滞较大,即种群的成熟期较长,则种群走向绝灭;若时滞较小,即种群的成熟期较短,则种群可以持续生存.
研究瞭一箇具有階段結構和時滯的幼年染病單種群模型.通過常微分方程的特徵根法,藉助幾何圖形分析瞭3箇平衡點的存在性,得到瞭它們跼部穩定的充要條件.併且在推論中找到瞭參數τ影響平衡點穩定性的閾值,得到瞭噹參數τ在不同區間取值時對應的平衡點的穩定性,併通過例題驗證瞭定理的結論.最後,對于所得的數學結果給齣瞭生物意義下的解釋:若時滯較大,即種群的成熟期較長,則種群走嚮絕滅;若時滯較小,即種群的成熟期較短,則種群可以持續生存.
연구료일개구유계단결구화시체적유년염병단충군모형.통과상미분방정적특정근법,차조궤하도형분석료3개평형점적존재성,득도료타문국부은정적충요조건.병차재추론중조도료삼수τ영향평형점은정성적역치,득도료당삼수τ재불동구간취치시대응적평형점적은정성,병통과례제험증료정리적결론.최후,대우소득적수학결과급출료생물의의하적해석:약시체교대,즉충군적성숙기교장,칙충군주향절멸;약시체교소,즉충군적성숙기교단,칙충군가이지속생존.
A delayed stage-structured single-species model with disease in the infant is studied. By the method of eigenvalue for ordinary differential equation, and by the geometric figures, the sufficient and necessary conditions for the existence and stability of the three equilibrium points are got. In the inference, some thresholds for the parameter τ are found, which control the stability of the equilibrium points. When the parameter τ has different values, the corresponding stability property of the equilibrium points is obtained, and theoretical result is verified by a simple example. At last, the results from the viewpoint of biology are explained. If the delay is large enough and the maturation period is long enough, then the population will die out. If the delay is small and the maturation period is short, then the population may persist.