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Global navigation satellite system technology has been widely used for high-precision, real-time monitoring of landslides. To improve forecasts and early warnings, the true deformation features must be extracted from the global navigation satellite system monitoring series. However, as the deformation rate changes at different creep stages, the relationship between noise and true deformation may also change, making it difficult to accurately describe the deformation. In this study, an adaptive sliding window algorithm is proposed to account for this relationship change. First, the window was defined with an equal window width and step length, which improved the efficiency of feature extraction. Second, the median and normalized interquartile ranges were used to estimate the window samples and obtain a continuous and reliable series. Finally, the window sample breakdown point was defined to adjust the window parameter. These steps were repeated for the adjusted window to achieve adaptive processing of the monitoring series. The results based on both simulated and real landslide monitoring series demonstrated that the proposed method can provide adaptive, robust, and reliable deformation information for landslide warnings. The adaptive sliding window method also successfully assisted in the early warning of a loess landslide in Heifangtai, Gansu province, northwest of the Chinese Loess Plateau, indicating its practical application potential.

This research takes the current social network development and education informatization as Beijing. This research takes Guangzhou’s higher vocational tourism teachers as the main body of research. The interview method was used to obtain relevant information and data. Through data analysis and comparison, two main problems were found: From the perspective of teachers, teachers’ attention to information literacy is mainly in the use of information technology, but not enough attention to basic knowledge, information ethics, etc.; the level of information technology skills of teachers is not high. From a school perspective, the school lacks enough attention to teacher information literacy, lack of regular training of information technology skills, and lack of relevant information technology hardware. In this regard, this research proposes corresponding countermeasures: popularize the application of teaching information technology; improve teacher information literacy, develop teacher teaching information technology ability training; formulate higher vocational teacher information literacy evaluation standards, and include teacher information literacy into the teacher assessment system.

Four new BDS II satellites have been launched which are named C31 (IGSO), C32 (IGSO), C33 (MEO) and C34 (MEO) separately. Their data qualities would affect the process of BDS globalization directly. In order to analyze the observation data quality of new navigation satellites, four indexes have been processed which contain data integrity rate, multipath, signal-to-noise ratio (SNR) and cycle slip ratio. The OBSQC software was developed to process the iGMAS data from September 8, 2016 to October 8, 2016. The experiment results show that the B1 and B3 data integrity rates of new navigation satellites are better than 95%. The SNR results of the new IGSO satellites are better than that of the IGSO working satellites while the SNR results of the new MEO satellites are quite similar to that of the MEO working satellites. In addition, the SNR values of the MEO satellites are better than that of the GPS MEO satellites. As for the multipath error, the results of the new navigation satellites are slightly better than that of the BDS working satellites and the GPS satellites.

In single-frequency precise-point positioning of a satellite, ionosphere delay is one of the most important factors impacting the accuracy. Because of the instability of the ionosphere and uncertainty of its physical properties, the positioning accuracy is seriously limited when using a precision-limited model for correction. In order to reduce the error, we propose to introduce some ionosphere parameter for real-time ionosphere-delay estimation by applying various mapping functions. Through calculation with data from the IGS (International GPS Service) tracking station and comparison among results of using several different models and mapping functions, the feasibility and effectiveness of the new method are verified.

GPS/GLONASS Common view, all in view and PPP Time Transfer technology are widely used in the remote time comparison. With the benefit of the high precise measurement on carrier phase, the PPP time transfer technology which based on the carrier phase data has been used in the International time comparison for TAI computation. In this Paper, The Carrier Phase Time Transfer on BeiDou Navigation satellite system (BDS) is implemented. The technology is referenced with GPS carrier phase time transfer method Precise Point Position (PPP) and combined with dual-frequency observation from the BeiDou Navigation Satellite system. The broadcast ephemeris and precise orbits and clock data are used for calculation and comparison. The performance of this time transfer technology is analyzed on the respect of precise, frequency accuracy and stability. Compared with the BDS Common View and GPS Common View, the result of BeiDou carrier phase time transfer is verified and shows its better performance.