di/dt and ΔI protection of DC traction supply system for metro vehicles;

The application of LOGO! in the DC traction SCADA of urban rail transit

The calculation of short-circuit current in DC traction network offers an important basis for the selection of electrical equipment,the design of protective-relay device and the decision for operation mode of traction substation.

Based on the author s experience in adjustment test and the study on the diagram of diagnosis and detection of shortcircuit,the principles of coordination between diagnosing and detecting shortcircuit and automatic reclosing in D.

The paper introduces the research and applications of piezoelectric ceramics in ignition and detonation, and summarize some effective methods for improving the properties and ageing of ceramic ma terials.

In order to analyze the effect of material models,arithmetic methods and mesh sizes on the results and precision,the detonation process of covered charge impacted by cylindrical steel fragment with flat head was simulated by non-linear dynamic analysis program LS-DYNA3D.

Detonatiory of charge behind the target plate is then studied, and a formula for calculating the detonation velocity is educed.

Jet initiation process of TATB and X02 (mixture of TATB and HMX)explosives is simulated by means of the Lagrange 2D-FPM code,the equation of state of TATB and the chemical rate function being as listed in reference 1.

Using the method of ALE arithmetic of LS-DYNA to simulation the formation process and the initiation process of shelled explosive of shaped charge jet.