It is known that predator-prey systems with constant rate harvesting exhibit very rich dynamics. On the other hand, incorporating time delays into predator-prey models could induce instability and bifurcation. In this paper we are interested in studying the combined effects of the harvesting rate and the time delay on the dynamics of the generalized Gause-type predator-prey models and the Wange...

rice is a main food for iranian people and has an important role in providing food security. regarding the population growth, increase of rice production and reduction of losses have special importance in prevention of rice import. rice losses in the harvest stage are the highest through the whole production period of this crop and hence the reduction of these losses is necessary. provision of ...

Background: Hyssop (Hyssopus officinalis L.) is herbaceous perennial plants of Lamiaceae family grown in Europe, the Middle East, Asia, and Northern Africa. Objective: In this research, the effect of harvesting time was studied on essential oil, photosynthetic pigment, and some morphological characteristics of hyssop. Methods: A Field experiment was carried out during 2015/2016 at the Res...

This study was conducted to find the effects of fruit ripening and extraction method on the quantity and quality of the Koroneiki olive oil. The oil samples extracted in six ripening stages were used for further quality analysis. Quality assessment of the oil was conducted according to the standard methods and the composition of fatty acids was measured by gas chromatography. The results showed...

one of the important bottle-necks in production of microalgae based biodiesel is thelack of an efficient method for harvesting of microalgae from the culture medium. in thisstudy, the electroflocculation method was developed for harvesting of microalgaedunaliella cells from culture medium. the effect of several parameters such as thecurrent density, electrical conductivity of culture medium, ti...

this paper deals with a delayed ratio-dependent functional response predator-prey model with a threshold harvesting policy. we study the equilibria of the system before and after the threshold. we show that the threshold harvesting can improve the undesirable behavior such as nonexistence of interior equilibria. the global analysis of the model as well as boundedness and permanence properties a...

Energy consumption is one of the primary concerns in the deployment of futuristic wireless sensor networks. On one hand due to advent of technologies such as Internet of Things (IoT), there has been tremendous growth in development of wireless sensor nodes, however, on the other hand these nodes are energy constrained, hence have limited lifetime. Energy harvesting from radio frequency (RF) sig...

This paper deals with a delayed ratio-dependent functional response predator-prey model with a threshold harvesting policy. We study the equilibria of the system before and after the threshold. We show that the threshold harvesting can improve the undesirable behavior such as nonexistence of interior equilibria. The global analysis of the model as well as boundedness and permanence properties a...

AIM We sought to evaluate our experience with endoscopic radial artery harvesting for coronary artery bypass grafting (CABG). METHODS From October 2005 to June 2010, 50 patients who underwent endoscopic radial artery harvesting for an elective CABG were prospectively assessed for harvesting characteristics, complications, postoperative and mid-term outcomes. RESULTS There were 34 (68%) male...