Multi-rotor drones are increasingly becoming a threat to critical facilities while bringing convenience. This article focuses on the difficulty of tracking and detecting low slow small unmanned aerial vehicles （UAVs）， and develops a UAV tracking， detection， recognition， and positioning system based on microphone array sound source localization. The system acquires UAV noise signals in real time， and then uses a wavelet transform-based beamforming time-frequency sound source localization algorithm for UAV noise source localization， and finally integrates the position of the multi-rotor UAV obtained by inversion of the microphone array and the image captured by the video. Tests conducted in a fully anechoic room have shown that the positioning system can accurately track the lateral flight and up-and-down flight of drones， accurately detect the position of drones even in blind spots of cameras， and effectively compensate for video detection. And the positioning accuracy of the system is 92.2%， which is better than that of similar systems.

Methods based on random forest and gradient boosting regression tree are proposed in order to improve the problem of subjective experience and high cost of calculation time in the effectiveness evaluation of anti-ship missile.By constructing a 3-layer and 19-component anti-ship missile effectiveness evaluation index system,240 operational parameter data samples of anti-ship missile in different states are set up by the improved ADC evaluation model,then the data set is segmented and normalized,combining with cross validation and grid search,two ideal decision tree integration effectiveness evaluation models are obtained.In the simulation test,the accuracy of the two models is high,which proves the practicability of the method and provides new ideas for anti-ship missile effectiveness evaluation.

To study the calculation method of launch window in space fly-by problem, and the influence of different initial phase angles on it, a method is proposed. The general variable law to solve the Lambert problem is studied. On this basis, the process and timing sequence of space fly-by are analyzed. A method to calculate the launch window satisfying the constraints of fuel consumption and fly-by time is proposed with the influence of different initial phase angles. The length and region of launch window can be obtained through the method. Simulation results indicate that the method is effective and can provide valuable references for the orbital planning and design of space fly-by missions.