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Due to the influence of the installation process and the use environment, the cable joints of the ring network cabinet often have a vicious accident of burning the cable joints. In order to find out the fault information of the cable joint as early as possible and avoid the occurrence of the burning fault, an online monitoring device for the temperature rise of the cable joint is designed, the device compares the temperature of the three-phase cable joint with the ambient temperature by monitoring, it can overcome the influence of ambient temperature on the temperature rise monitoring of cable joints, at the same time, the radio frequency technology is used to transmit the temperature information of the cable joint, which solves the physical isolation problem of high and low voltage. Using narrow-section CT, based on the saturation technology, the high current is limited, and the power supply problem of the temperature measurement sensor is solved. The online monitoring device based on embedded technology has been applied and tested on site to meet the requirements of the online monitoring of the temperature rise of the cable joint of the ring network cabinet, it has important significance for power supply safety.

As a new-style counter-personnel non-lethal weapon, it is the non-steady characteristic and large water mist field that increase the difficulty of measuring the droplet size distribution of impulse anti-riots water cannon which is the most important index to examine its tactical and technology performance. A method based on the technologies of particle scattering, sheet laser imaging and high speed handling was proposed and an universal droplet size measuring algorithm was designed and verified. According to this method, the droplet size distribution was measured. The measuring results of the size distribution under the same position with different timescale, the same axial distance with different radial distance, the same radial distance with different axial distance were analyzed qualitatively and some rational cause was presented. The droplet size measuring method proposed in this article provides a scientific and effective experiment method to ascertain the technical and tactical performance and optimize the relative system performance.

Through Computational Fluid Dynamic(CFD) simulation method, One-Equation Large Eddy Simulation(LES) model coupled with the bounded and compressed VOF method was used to simulate the near-field of impulse anti-riots water cannon for the study of its operational properties and application. The instantaneous isosurfaces of liquid-phase volume fraction and the high-speed photographs were compared. They are agreed with each other in the spray configuration and jet penetration length. The spray process is divided into three phases: liquid column burst, secondary burst, liquid film rupture. The inflation of the highpressure gas is considered to be the most dominant factor in the near-field. The influence of initial conditions on the atomization characteristics was investigated by condition-changing simulation. The conclusions provide guidance for further study and its operational application.