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The strapdown inertial navigation systems (SINS) have been widely used for many vehicles, such as commercial airplanes, Unmanned Aerial Vehicles (UAVs), and other types of aircrafts. In order to evaluate the navigation errors precisely and efficiently, a predictionmethod based on support vectormachine (SVM) is proposed for positioning error assessment. Firstly, SINS errormodels that are used for error calculation are established considering several error resources with respect to inertial units. Secondly, flight paths for simulation are designed. Thirdly, the ∊-SVR based prediction method is proposed to predict the positioning errors of navigation systems, and particle swarm optimization (PSO) is used for the SVM parameters optimization. Finally, 600 sets of error parameters of SINS are utilized to train the SVMmodel, which is used for the performance prediction of newnavigation systems. By comparing the predicting results with the real errors, the latitudinal predicting accuracy is 92.73%, while the longitudinal predicting accuracy is 91.64%, and PSO is effective to increase the prediction accuracy compared with traditional SVM with fixed parameters. This method is also demonstrated to be effective for error prediction for an entire flight process. Moreover, the prediction method can save 75% of calculation time compared with analyses based on error models. [ABSTRACT FROM AUTHOR]

In this study, embryogenic cell aggregates obtained from the established embryogenic cell suspension culture system of Anthurium andraeanum 'Alabama'' were used as experimental materials to investigate the effects of kanamycin and hygromycin on survival rate of cell aggregates, somatic embryogenesis and plantlet regeneration of A. andraeanum. According to the results, at the embryonic cell propagation stage, lethal doses of kanamycin and hygromycin to embryogenic cell aggregates of A. andraeanum were 200 and 60 mg/L, respectively; at the differentiation stage, either 150 mg/L kanamycin or 40 mg/L hygromycin could inhibit somatic embryogenesis; either 100 mg/L kanamycin or 20 mg/L hygromycin could inhibit plantlet regeneration. These results provided important reference for further studies of transgenic A. andraeanum. [ABSTRACT FROM AUTHOR]

In this study, an embryogenic callus induction and proliferation system for Hippeastrum vittatum was established, with the tender bulbs as expiants. And then the sensitivity of the expiants and calli to kanamycin and hygromycin was evaluated. The results suggested that the embryogenic calli were induced from tender bulbs and cultured in Murashige and Skoog (MS) medium supplemented with 0.5 mg/L N-phenyl-N'-l, 2,3-thiadiazol-5-ylurea (TDZ), 1.0 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D), and 30 g/L sucrose (pH5.8) in the dark at 25 ± 1°C. Further study of the influence of kanamycin and hygromycin on callus induction and multiplication showed that, the lethal doses of kanamycin and hygromycin to bulb expiants were 100 and 30 mg/L, respectively. All expiants of H. vittatum died on the medium supplemented with 100 mg/L kanamycin or 30 mg/L hygromycin at the induction stage, and callus proliferation was completely inhibited by 100 mg/L kanamycin or 25 mg/L hygromycin, and all the calli died at last. These results will provide important reference for further studies of transgenic H. vittatum. [ABSTRACT FROM AUTHOR]