is known as Hutchinson’s equation, if r and K are positive constants and h(t) = t− τ for a positive constant τ. Hutchinson’s equation has been investigated by several authors (see, e.g., [13, 14, 18, 23]). Delay logistic equation (1.1) was studied by Gopalsamy and Zhang [7, 25] who gave sufficient conditions for the oscillation and the nonoscillation of (1.1). Publications [1, 2, 3, 4, 5, 6, 10...

The aim of this paper is to present some approaches to tumour growth modelling using the logistic equation. As the first approach the well-known ordinary differential equation is used to model the EAT in mice. For the same kind of tumour, a logistic equation with time delay is also used. As the second approach, a logistic equation with diffusion is proposed. In this case a delay argument in the...

An Ambrosetti-Prodi type exact multiplicity result is proved for a diffusive logistic equation with harvesting. We show that a modified diffusive logistic mapping has exactly either zero, or one, or two pre-images depending on the harvesting rate. It implies that the original diffusive logistic equation with harvesting has at most two positive steady state solutions.