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The assembly process file is a direct expression of the product assembly design intent. In order to improve the quality and efficiency of the assembly, the 3D model of the product and resources needs to be introduced into the virtual assembly environment. However, the assembly process is verified and optimized by assembly simulation. In order to realize the intelligent analysis of assembly process files and the automation of assembly simulation, an intelligent analysis method of assembly process based on semantic elements is proposed. This article takes the assembly process documentation of complex products as the research object. An improved TF-IDF algorithm is proposed to automatically extract key semantic elements in the assembly process file. We quickly resolve previous assembly process data by building assembly key semantic corpora. An assembly semantic dependency tree algorithm based on maximum entropy is proposed to automatically reason the logical relationship of each assembly phrase in the assembly process statement. According to the above algorithm, the assembly semantic intelligent analysis system is developed. The assembly process of a certain type of ground weapon system is taken as an example to verify the system. And the intelligent analysis of the product process file is realized which lays a foundation for realizing the semantic driving of product assembly simulation.

To make ionic liquids (ILs) accessible and economical, ethylene glycol was mixed in 1-ethyl-3-methylimidazolium-dicyanamide ([EMIm]DCA) to obtain droplets that could experimentally collide white fuming nitric acid. To investigate the ignition delay (ID) time theoretically in terms of hydrodynamics, alcohol fuels and kerosene were used as combustibles, while the intermiscibility between them and nitric acid (HNO 3 ) was calculated using the ternary phase-field method alongside finite element analysis. The specific impulses of blend fuels were calculated by a thermodynamic method and compared to ILs. When the droplet was ethylene glycol/ [EMIm]DCA with a 2.1 mm diameter and a 1.69 m/s colliding velocity, the ID time was the shortest. Kerosene was not an applicable additive for [EMIm]DCA owing to its lower intermiscibility with ILs and HNO 3 than alcohol fuels; alcohol fuels, however, were appropriate. The concentration of ethylene glycol in the oxidizer pool increased faster than the concentration of propylene glycol, triggering more rapid hypergolic ignition in the first 50 ms. The protocols regarding the hypergolic ignition conditions were verified, i.e., the size of the droplet had to be minute when the colliding velocity was as fast as possible; this was carefully calculated using ethylene glycol. According to thermodynamic calculations, the addition of alcohol fuels can improve the specific impulse of fuels, with ethylene glycol performing the best. The feasibility of adding alcohol fuels to ILs was confirmed via experiments and thermodynamic computations, with the simulation results providing some guidance on selecting the experimental or engineering conditions or both.

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