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In this paper, we consider a three-population food chain model which concerning about impulsive releasing predators (natural enemies) at fixed moment. By using the Floquet theory and the comparison theorem of impulsive differential equation, conditions for global asymptotic stability of pest-eradication periodic solution and permanence of the system are obtained. Finally, the explanation of its biological...
It is widely regarded that evaluation is a complex systematic project, which involving many aspects of the process in technological innovation, epically for the pharmaceutical sector. Based on 18 original-designing indicators and the Factor analysis, the paper evaluates the stage differences of continuous innovation abilities in Chinese hinterland provinces' biotechnology industry. And then it originally...
Based on the classical epidemic mode, a new epidemic model of forest which integrates Monochamus Alternatus Hope with Pines was established. The expression of the critical threshold was found. It is proved that, when the critical threshold less than 1, the disease free equilibrium is locally asymptotically stable, and when the critical threshold more than 1, the insect pests equilibrium is locally...
High speed development of economy and huge population has made China become one of the biggest electronic consuming markets as well as the greatest e-waste generator gradually. About 20 million electronic household appliances and 70 million cell phones come to their end-of-life every year since 2001. However, China has not set up an integrated and effective reverse logistics system to collect, transport...
Special equipments mean equipments that are dangerous and relating to lives such as boiler, pressure container, elevator, crane, and the passenger ropeways. The method of weighted average analysis is used in the artificial neural network (ANN) model of the risk assessment for special equipments. In this method the adopted weights are all based on expert experience, so the assessment time is too long...
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