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Aiming at the lack of research on the assignment model of drilling rig scheduling tasks in China, and it is difficult to meet the field requirements of this model in practical applications, a drilling rig scheduling task assignment optimization scheme combining Kmeans algorithm and ACO algorithm is established. Firstly, the wellhead coordinate data in the well site is divided into blocks using the clustering feature of Kmeans, and the algorithm optimization coefficient is determined by the required number of wells in the block. Secondly, the ant colony algorithm is used to calculate and plan the paths for the wellheads in different blocks to realize the optimization of the ant colony algorithm. The results show that compared with the traditional ant colony, the rig scheduling task allocation model established by the Kmeans-ACO algorithm has a smaller distance and a better path.

To develop an eco-friendly drilling fluid additive, shaddock peel was modified and was used in water-based drilling fluid in this work. The shaddock peel has obvious effects on rheological properties, filtration, and wall formation of drilling fluid. It also displays the inhibition of clay swelling, while the shaddock peel slurry is easy to ferment, mildew and so on. The performance of the shaddock peel slurry and moldy/fermented shaddock peel slurry in water-based drilling fluid were compared, which shows that the efficiency, such as the AV and PV, decrease obviously by more than 50%. The swelling rate of bentonite in the water extraction of moldy/fermented shaddock peel in 90 min is about 62%, which is obviously higher than the swelling rate of the non-mildew/fermented shaddock peel water extract, 46%. Then preservative was evaluated in shaddock peel slurry modified drilling fluid. The result indicates that the effect of moldy/fermentation on the viscosity and the inhibition of shaddock peel was obviously inhibited by the preservative. The combined sodium benzoate and formaldehyde can protect the shaddock peel slurry from mildew and fermentation, which can keep the performance of shaddock peel slurry in the drilling fluid.

The status of multi UAV cooperative cluster operation in the military field is more and more prominent. Its electronic interference to the radar network is always the focus of military electronic warfare. This paper studies the rules and characteristics of deceptive Jamming of multiple UAVs to radar network, and focuses on how to use the least number of UAVs to generate fake track deception to radar network. This paper starts with the geometric space relationship between the UAV and the radar network. Based on the geometric spatial relationship between the false track of UAV and radar network, a concise mathematical model is established, and the analysis and solution flow of the model is given, which provides important enlightenment for improving the electronic countermeasure capability of the grouped UAV.

With the gradual popularization of the application of intelligent air vehicle in various fields, the problems related to its application are becoming a hot research topic increasingly. Rapid path planning in complex environment is an important topic of intelligent air vehicle control. Because of the limitation of the system structure, the positioning system of this kind of air vehicle cannot locate itself accurately. Once the positioning error accumulates to a certain extent, it may lead to the failure of the mission. Therefore, it is an important task to correct the positioning error in the flight path planning of intelligent air vehicle. This paper makes a deep study on the problem of flight path planning. By simplifying the three-dimensional space problem into a two-dimensional plane geometry problem, the optimization mathematical model is established by using the dynamic decision optimization method, and the problem of how to plan the optimal flight path by using the known space correction points is analyzed in detail, which provides some enlightenment for optimizing the flight path, improving the flight success rate and improving the performance of the air vehicle.

The confrontation between group UAV cooperation and netted radar is always the focus of the game in the field of electronic warfare. In this paper, the model of multi UAV cooperative jamming netted radar system is studied, and the optimization model of how to generate false track by using the least number of UAVs is analyzed in detail to implement the optimal jamming to netted radar. Through the concise space physical relationship, the mathematical model which can be solved is established, which provides important enlightenment for improving the UAV jamming effect and improving the UAV Tactical performance.

The China Spallation Neutron Source (CSNS) has started commissioning in early 2018. The neutron spectrum from the tungsten target bombarded by a 1.6 GeV proton beam is very wide, namely with characteristics of a white neutron spectrum. In this paper two white neutron beams schemed at CSNS are simulated by using the FLUKA code. And the beam spectrum and intensity are compared with that from other neutron sources in the world. The fidelity for the chip irradiation experiments by using the neutron spectra of these two white-neutron beam lines is estimated. These atmospheric-like neutron beams will be the first white neutron beam lines at CSNS and more intensive ones for carrying out an accelerated test of the neutron-induced single event effect (SEE) will be available in a few years.