Labyrinth seal can cause steam-exciting, the structural and operating parameters of labyrinth seal have effect on stability of rotor-system. For investigating the coupling influences of the structure and operating par...Labyrinth seal can cause steam-exciting, the structural and operating parameters of labyrinth seal have effect on stability of rotor-system. For investigating the coupling influences of the structure and operating parameters of labyrinth seals on dynamic coefficients, a model of calculating dynamic coefficients of labyrinth seals is presented using a two control volume model. The coupling influences of parameters on cross-coupled stiffness and direct damping of labyrinth seal are discussed. In the conclusion, a reference of preventing steam-exciting vibration and optimum determination of design parameters of labyrinth seals are provided.展开更多
Taking the construction of new liberal arts as a background,this paper proposes that the international economy and trade major should optimize the teaching system and personnel training mechanism by adding the new cro...Taking the construction of new liberal arts as a background,this paper proposes that the international economy and trade major should optimize the teaching system and personnel training mechanism by adding the new cross-border e-commerce direction.This paper highlights the development path of high-quality international economy and trade professional training,and further ensures the first-class talent training and first-class professional construction specialty.展开更多
The consensus problem for fractional multi-agent systems(MASs)with time delay is considered.The distributed fractional proportional-integral(PI)-type controller is designed so that the consensus of the proposed system...The consensus problem for fractional multi-agent systems(MASs)with time delay is considered.The distributed fractional proportional-integral(PI)-type controller is designed so that the consensus of the proposed systems is achieved.Moreover,explicit condition to determine the crossing directions is developed.The results show that with the increase of time delay,the closed-loop system has two different dynamic characteristics:From consensus to nonconsensus and consensus switching.Furthermore,delay margin within which consensus of MASs will always hold is determined.The results should provide useful guidelines in the consensus analysis and in the analytical design of the distributed controllers.展开更多
基金This project is supported by National Natural Science Foundation of China(59990472). Manuscript received on November 30, 1999 r
文摘Labyrinth seal can cause steam-exciting, the structural and operating parameters of labyrinth seal have effect on stability of rotor-system. For investigating the coupling influences of the structure and operating parameters of labyrinth seals on dynamic coefficients, a model of calculating dynamic coefficients of labyrinth seals is presented using a two control volume model. The coupling influences of parameters on cross-coupled stiffness and direct damping of labyrinth seal are discussed. In the conclusion, a reference of preventing steam-exciting vibration and optimum determination of design parameters of labyrinth seals are provided.
基金supported by Laboratory construction project of Shandong University of Technology"Cross border e-commerce B2C platform product operation simulation experiment construction"(2020018).
文摘Taking the construction of new liberal arts as a background,this paper proposes that the international economy and trade major should optimize the teaching system and personnel training mechanism by adding the new cross-border e-commerce direction.This paper highlights the development path of high-quality international economy and trade professional training,and further ensures the first-class talent training and first-class professional construction specialty.
基金supported in part by the National Natural Science Foundation of China under Grant Nos.61773207,62173183the Natural Science Fund for Distinguished Young Scholars of Jiangsu Province under Grant No.BK20190020.
文摘The consensus problem for fractional multi-agent systems(MASs)with time delay is considered.The distributed fractional proportional-integral(PI)-type controller is designed so that the consensus of the proposed systems is achieved.Moreover,explicit condition to determine the crossing directions is developed.The results show that with the increase of time delay,the closed-loop system has two different dynamic characteristics:From consensus to nonconsensus and consensus switching.Furthermore,delay margin within which consensus of MASs will always hold is determined.The results should provide useful guidelines in the consensus analysis and in the analytical design of the distributed controllers.
