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This paper proposes a manufacturing technology plan based on the combination of 3D printing and precision cutting for a certain projectile fairing part with a thin-walled cavity structure. By holistically taking into account the process and design requirements, on the one hand, the process structure required for 3D printing and precision cutting is incorporated into the original design plan to improve the manufacturability of parts; on the other hand, the comprehensive research of the process plan, processing strategy, process equipment can solve the manufacturing difficulties during the product development, which not only ensures the realization of the lightweight product design structure, but also meets the requirements of the precision assembly and product usage.

Because of using correlation processing technology, it is difficult for traditional jamming patterns to achieve the desired jamming effect on phase coded radar. At present, the forward deception jamming of phase coded radar is mainly realized by uniform interrupted sampling repeater jamming (UISRJ). In order to solve the problem that the UISRJ can only produce a single and delayed false target, a kind of non-uniform interrupted sampling repeater jamming (NUISRJ) is proposed. The non-uniform sampling pulse train is generated through pseudo random sequence, and then sampled and forwarded to generate jamming signal, which is processed by radar pulse compression to form dense false targets. Combining the theoretical analysis and simulation results, it can be seen that the NUISRJ has the dual effects of suppressing jamming and spoofing jamming, and the distribution of false target string is more random, including the leading and lagging false target. The amplitude and coverage area of false targets group can be controlled by adjusting sampling pulse width and forwarding times to effectively implement jamming.

This study investigated the effects of ramie (0, 3, 6, 9, or 12%) included in finishing diets on carcass traits and meat quality of Xiangcun black pigs. Results showed that ramie decreased (linear, P .05) backfat depth while it increased (linear, P .05) loin-eye area. A quadratic effect of shear force in longissimus thoracis (LT) was observed, and the lowest value was noted in the 6% ramie group. Protein content in LT was linearly increased by ramie (linear, P .01). Meanwhile, dietary ramie linearly decreased lipogenic genes mRNA levels and fiber cross-sectional area, but it linearly increased total fiber number of LT. These results suggest that ramie included in the diet9% is an effective feed crop to partly improve carcass trait and muscle chemical composition without negatively affecting growth performance, and the underlying mechanism may be due to the changed lipogenic potential and myofiber characteristics induced by ramie.