Aero-optic imaging deviation prediction based on ISSA-ELM

When the aircraft is moving at high speed in the atmosphere, aero-optical imaging deviation will appear due to the influence of aero-optical effect. In order to achieve real-time compensation during the flight of the aircraft, it is necessary to analyze and predict the obtained imaging deviation data. In order to improve the search speed and accuracy of the prediction algorithm and the ability to jump out of local optimum, in this paper, an improved sparrow search algorithm optimized extreme learning machine (ISSA-ELM) neural network model is proposed to predict the aero-optical imagine deviation. Finally, the performance of ISSA-ELM, ELM neural network and SSA-ELM neural network was tested. The results showed that compared with ELM and SSA-ELM algorithms, the convergence speed of ISSA-ELM was significantly enhanced, and the accuracy of data prediction was also significantly improved.     

莴苣茎水溶性多糖的单糖组成及免疫调节活性研究

为了探究莴苣茎中多糖类物质,以莴苣茎为原料,水提醇沉法制备得到莴苣茎水溶性多糖,高效液相色谱法分析多糖的单糖组成,小鼠巨噬细胞RAW264.7给药试验研究多糖的免疫调节活性。结果表明:莴苣茎水溶性多糖主要由半乳糖醛酸、半乳糖和阿拉伯糖组成,其摩尔比为22.6030.4217.88;在试验的浓度范围内(5~200μg/mL),莴苣茎水溶性多糖可以显著提高小鼠巨噬细胞活力和吞噬中性红的能力,并刺激小鼠巨噬细胞分泌产生NO,表明其具有免疫调节活性。该研究结果可为莴苣茎的高效利用和产品开发提供理论依据。