There are magnetic interference problems in the applications of DC current comparator. Analysis on the magnetic effectiveness which is applied by the external magnetic field is introduced in this paper. The effectiven...There are magnetic interference problems in the applications of DC current comparator. Analysis on the magnetic effectiveness which is applied by the external magnetic field is introduced in this paper. The effectiveness is proved by the actual results which are compared with the magnetic- circuit method and the finite element method. In addition, the reference comment is given which can be used in the practical work of DC current comparator shield design.展开更多
Trajectories of flying hot particles were predicted in this work, and the temperatures during the movement were also calculated. Once the particle tem- perature decreased to the critical temperature for a hot particle...Trajectories of flying hot particles were predicted in this work, and the temperatures during the movement were also calculated. Once the particle tem- perature decreased to the critical temperature for a hot particle to ignite building insulation materials, which was predicted by hot-spot ignition theory, the distance particle traveled was determined as the minimum safety distance for preventing the ignition of building insulation materials by hot particles. The results showed that for sphere aluminum particles with the same initial velocities and diameters, the horizontal and vertical distances traveled by particles with higher initial tem- peratures were higher. Smaller particles traveled farther when other conditions were the same. The critical temperature for an aluminum particle to ignite rigid polyurethane foam increased rapidly with the decrease of particle diameter. The horizontal and vertical safety distances were closely related to the initial temper- ature, diameter and initial velocity of particles. These results could help update the safety provision of firework display.展开更多
Aiming at the deficiencies of notch filters on the aspect of vibration suppression for elastic missile with swing nozzle thrust vector control(SNTVC),an active vibration controller(AVC)is proposed.It is composed of an...Aiming at the deficiencies of notch filters on the aspect of vibration suppression for elastic missile with swing nozzle thrust vector control(SNTVC),an active vibration controller(AVC)is proposed.It is composed of an optimal state feedback controller(OSFC)and an optimal minimal order state observer(OMOSO),which can be respectively designed based on the separation principle.The design rules of these two elements are successively given.Computer simulation results present that AVC can realize strong vibration suppression and good convergence property after disturbing.Moreover,it has simple design and then it is easily implemented in engineering.In addition,the AVC scheme can also resolve the poor system stability to a great extent,which is resulted from the bad static stability of missile body.展开更多
文摘There are magnetic interference problems in the applications of DC current comparator. Analysis on the magnetic effectiveness which is applied by the external magnetic field is introduced in this paper. The effectiveness is proved by the actual results which are compared with the magnetic- circuit method and the finite element method. In addition, the reference comment is given which can be used in the practical work of DC current comparator shield design.
基金supported by the National Basic Research Program of China(2012CB719702)the International Science&Technology Cooperation Program of China(2014DFG72300)the Fundamental Research Funds for the Central University(WK2320000014)
文摘Trajectories of flying hot particles were predicted in this work, and the temperatures during the movement were also calculated. Once the particle tem- perature decreased to the critical temperature for a hot particle to ignite building insulation materials, which was predicted by hot-spot ignition theory, the distance particle traveled was determined as the minimum safety distance for preventing the ignition of building insulation materials by hot particles. The results showed that for sphere aluminum particles with the same initial velocities and diameters, the horizontal and vertical distances traveled by particles with higher initial tem- peratures were higher. Smaller particles traveled farther when other conditions were the same. The critical temperature for an aluminum particle to ignite rigid polyurethane foam increased rapidly with the decrease of particle diameter. The horizontal and vertical safety distances were closely related to the initial temper- ature, diameter and initial velocity of particles. These results could help update the safety provision of firework display.
文摘Aiming at the deficiencies of notch filters on the aspect of vibration suppression for elastic missile with swing nozzle thrust vector control(SNTVC),an active vibration controller(AVC)is proposed.It is composed of an optimal state feedback controller(OSFC)and an optimal minimal order state observer(OMOSO),which can be respectively designed based on the separation principle.The design rules of these two elements are successively given.Computer simulation results present that AVC can realize strong vibration suppression and good convergence property after disturbing.Moreover,it has simple design and then it is easily implemented in engineering.In addition,the AVC scheme can also resolve the poor system stability to a great extent,which is resulted from the bad static stability of missile body.