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Under the background of double carbon, it is important to study forest pests and diseases to improve forest carbon sink. In this paper, we establish a delayed model associated with the larvae and adults of Saperda populnea, susceptible poplars, and infected poplars. First, we analyze the existence and stability of the equilibrium of the model. Second, we study the existence of Hopf bifurcation near the equilibrium and obtain the normal form of Hopf bifurcation by the multiple time scales method. Then, we analyze the direction and stability of Hopf bifurcating periodic solutions. Third, we analyze and conjecture some parameter values based on official data, and carry out numerical simulations to verify our results. Finally, we give some suggestions on the prevention and control of Saperda populnea. [ABSTRACT FROM AUTHOR]

Power conditioning system (PCS) is the crucial component of superconducting magnetic storage system (SMES), which determines its power control performance and ability. This paper investigates the feasibility of applying Z source converter (ZSC) as the PCS for SMES. A ZSC-based PCS (ZSC-PCS) for SMES is presented, parameter design methods are analyzed, and a novel minimum power losses control scheme is proposed. By dynamically regulating open zero vector duty ratio to its minimum required level, the ZSC-PCS can enlarge both active and reactive power capability of SMES with lowest power losses. The feasibility of the proposed approach is verified by the experimental results on a kVA scale prototype. [ABSTRACT FROM AUTHOR]