Simultaneous wireless information and power transfer (SWIPT) is a promising technique to prolong the lifetime of energy‐constrained relay systems. Most previous works optimize power‐splitting (PS) scheme based on a linear or a simple two‐piecewise linear energy harvesting (EH) model, while the employed EH model may not characterize the properties of practical EH harvesters well. This leads to a mismatch between the existing PS scheme and the practical EH harvester available for relay systems. Motivated by this, this paper is devoted to the design of PS scheme in a nonlinear EH amplify‐and‐forward energy‐constrained relay system in the presence of a direct link between the source and the destination. In particular, we formulate an optimization problem to maximize the system capacity according to the instantaneous channel state information, subject to a nonlinear EH model based on the logistic function. The objective function of the formulated problem is proven to be unimodal and there is no closed‐form expression for the optimal PS ratio due to the complexity of logistic function. In order to reduce overhead cost of optimizing PS ratio, a simpler nonlinear EH model based on the inverse proportional function is employed to replace the nonlinear EH model based on the logistic function and we further derive the closed‐form expression for the optimal PS ratio. Simulation results reveal that a higher system capacity can be achieved when the PS scheme is optimized based on nonlinear EH models instead of the linear EH model, and that there is only a marginal difference between the capacity under the two optimal PS schemes optimized for two different nonlinear EH models.

According to actual requirements of the textile enterprise, a production management structure model based on multi-Agent is proposed by using the multi-Agent technology, relationship model, decision theory and expert system. Then, through comparing the existing information management system, the advantages of the system is also reflected, and the functional structure model of the system is optimized. Third, a flexible, dynamic, efficient collaboration management platform is designed. As verified by real application, production management and decision model based on multi-Agent strengthens the interactivity role both the user and the system, meets the requirements of the production management, intelligent decision and personalized service, and promotes the informatization development of production management of the textile enterprise.