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Armature is very important for a synchronous induction coil launcher which can transform the electric energy to kinetic energy and push the load forward. The structure of the armature will influence the kinetic energy conversion efficiency directly. This paper analyzes the armature structure of a capacitor-driven synchronous induction coil launcher. Length and thickness of the armature are analyzed that how these parameters influence the maximum velocity and system efficiency of the launcher. Current filaments model is used to calculate the motion characteristics of a tubular linear induction motors, which is verified by an experiment and finite-element code. Genetic algorithm optimizer is used to calculate the best trigger times of the coils and the maximum velocity under the conditions of different length and thickness of the armature. It is shown that when the armature mass is fixed, length and thickness of the armature will greatly increase the velocity of the armature. The best length of the armature should be almost 2–2.5 times the length of the coil. The best thickness of the armature could be estimated by skin depth.

In this study, a second water-soluble polysaccharide (designated as LDP-2) was isolated from the bulbs of Lanzhou Lily (Lilium davidii var. unicolor). Based on monosaccharide composition and methylation analysis, its structural features were investigated using a variety of characterizations, such as size-exclusion chromatography combined with laser light scattering (SEC-LLS), gas chromatography-mass spectroscopy (GC-MS), infrared (IR) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. The results demonstrate that LDP-2 is a homogeneous heteropolysaccharide (molecular weight 6.2 × 104 Da), which includes four kinds of monosaccharides (Lyx, Man, Glc, and Gal in an approximate weight ratio of 6.74: 6.28: 76.50: 10.48). Furthermore, its morphology, thermal behavior, and preliminary hypoglycemic activities were also investigated.

This paper analyzes the influences of the factors in a capacitor-driven multi-stage synchronous induction coilgun (SICG) and optimal combination of the design parameters based on orthogonal experiment design (OED). Finite element transient solver is used to calculate the motion characteristics of a multi-stage SICG. The muzzle speed is set to be the target of the optimization. System parameters (factors), levels and orthogonal array (OA) are determined by the order. Three optimization schemes are compared, including stage-by-stage optimization, section optimization and full optimization. Optimal combination of the three-stage SICG is obtained, as well as important order of factors. It shows that a set of comparatively better parameters and relatively higher efficiency could be achieved through orthogonal optimum. Wire diameter and coil diameter are the most important factors that influence the system efficiency of the launcher. Besides them, length of coil, trigger position and number of turns have less influence for the system in the important order. Section optimization could reduce the amount of computations compared to full optimization and a set of comparatively better parameters and relatively higher efficiency could be achieved. It is suggested to optimize a multi-stage SICG. How to choose the factors from lots of parameters is according to the engineering practice. Improper choices of the value in levels may cause unable to reach an optimum. The conclusion will be useful for coilgun design.

Situation analysis is a key technology in the battlefield situation surveillance system. It can explain the battlefield picture and judge the offensive intention of the enemy in the sea battlefield. The design and implementation of scenario production system for sea battlefield situation analysis is discussed in the paper. It aims to produce scenario for the sea battlefield situation analysis system. Firstly, some motion models for single target and formation target are created. Based on the models, a scenario production system for sea battlefield situation analysis is developed. Then a scenario is produced to be applyed to a function clustering algorithm for maneuvering target. The simulation result shows that the algorithm can distinguish target function clustering and discover the enemy’s offensive intention correctly.