Powder compaction is one of the most crucial processes in initiating explosive device manufacturing. The quality of powder compaction may influence the performances of product directly. Traditional powder compaction m...Powder compaction is one of the most crucial processes in initiating explosive device manufacturing. The quality of powder compaction may influence the performances of product directly. Traditional powder compaction mainly makes use of manual gravitational spiral loading machine or lever loading machine. Potential accident by the strike in powder compaction of initiating explosive device could risk life, property and the environment. To prevent this risk, automatic control system and control strategy can be used to guarantee no strike in pressing process. The scope of this paper is to analyze and review the control strategy for powder compact and discuss the experimental results for the application of the proposed strategy.展开更多
The amount of information required for reliability assessment of success/failure products is defined and the formula of equivalent information method is deduced. Based on the formula, a method for assessing reliabilit...The amount of information required for reliability assessment of success/failure products is defined and the formula of equivalent information method is deduced. Based on the formula, a method for assessing reliability of initiating explosive devices with small sample size is established. Compared with the assessment method for devices with large sample size, the new method is correct and feasible and can be used to assess the reliability of initiating explosive devices with high reliability requirements.展开更多
Concerning the issue of high-dimensions and low-failure probabilities including implicit and highly nonlinear limit state function, reliability analysis based on the directional importance sampling in combination with...Concerning the issue of high-dimensions and low-failure probabilities including implicit and highly nonlinear limit state function, reliability analysis based on the directional importance sampling in combination with the radial basis function （RBF） neural network is used, and the RBF neural network based on first-order reliability method （FORM） is to approximate the unknown implicit limit state functions and calculate the most probable point （MPP） with iterative algorithm. For good efficiency, based on the ideas that directional sampling reduces dimensionality and importance sampling focuses on the domain contributing to failure probability, the joint probability density function of importance sampling is constructed, and the sampling center is moved to MPP to ensure that more random sample points draw belong to the failure domain and the simulation efficiency is improved. Then the numerical example of initiating explosive devices for rocket booster explosive bolts demonstrates the applicability, versatility and accuracy of the approach compared with other reliability simulation algorithm.展开更多
To test the pulse signal of initiating explosive device (IED) in an aircraft,a multi-channel equivalent system for IED based on Gigabit Ethernet transmission is designed according to its electrical parameters. The out...To test the pulse signal of initiating explosive device (IED) in an aircraft,a multi-channel equivalent system for IED based on Gigabit Ethernet transmission is designed according to its electrical parameters. The output voltage of multi-channel equivalent circuit is converted by analog-to-digital converter (ADC). Then the validity of the converted signal is judged by field programmable gate array (FPGA). Finally,it is transmitted the host computer through Gigabit Ethernet for waveform displaying. Compared with the traditional equivalent equipment of IED,the designed system here can not only test the validity of the pulse signal and normal operation of equivalent circuit,but also realize fast and reliable analysis of pulse signal by means of Gigabit Ethernet. It solves the problems of low speed and lag of response of traditional equivalent equipment.展开更多
文摘Powder compaction is one of the most crucial processes in initiating explosive device manufacturing. The quality of powder compaction may influence the performances of product directly. Traditional powder compaction mainly makes use of manual gravitational spiral loading machine or lever loading machine. Potential accident by the strike in powder compaction of initiating explosive device could risk life, property and the environment. To prevent this risk, automatic control system and control strategy can be used to guarantee no strike in pressing process. The scope of this paper is to analyze and review the control strategy for powder compact and discuss the experimental results for the application of the proposed strategy.
基金Supported by the Ministerial Level Foundation(9140C3705041003)
文摘The amount of information required for reliability assessment of success/failure products is defined and the formula of equivalent information method is deduced. Based on the formula, a method for assessing reliability of initiating explosive devices with small sample size is established. Compared with the assessment method for devices with large sample size, the new method is correct and feasible and can be used to assess the reliability of initiating explosive devices with high reliability requirements.
文摘Concerning the issue of high-dimensions and low-failure probabilities including implicit and highly nonlinear limit state function, reliability analysis based on the directional importance sampling in combination with the radial basis function （RBF） neural network is used, and the RBF neural network based on first-order reliability method （FORM） is to approximate the unknown implicit limit state functions and calculate the most probable point （MPP） with iterative algorithm. For good efficiency, based on the ideas that directional sampling reduces dimensionality and importance sampling focuses on the domain contributing to failure probability, the joint probability density function of importance sampling is constructed, and the sampling center is moved to MPP to ensure that more random sample points draw belong to the failure domain and the simulation efficiency is improved. Then the numerical example of initiating explosive devices for rocket booster explosive bolts demonstrates the applicability, versatility and accuracy of the approach compared with other reliability simulation algorithm.
文摘To test the pulse signal of initiating explosive device (IED) in an aircraft,a multi-channel equivalent system for IED based on Gigabit Ethernet transmission is designed according to its electrical parameters. The output voltage of multi-channel equivalent circuit is converted by analog-to-digital converter (ADC). Then the validity of the converted signal is judged by field programmable gate array (FPGA). Finally,it is transmitted the host computer through Gigabit Ethernet for waveform displaying. Compared with the traditional equivalent equipment of IED,the designed system here can not only test the validity of the pulse signal and normal operation of equivalent circuit,but also realize fast and reliable analysis of pulse signal by means of Gigabit Ethernet. It solves the problems of low speed and lag of response of traditional equivalent equipment.
