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Based on theory of hypothesis testing, a function of calculating probabilities of two types of errors is proposed, which is adopted inanalyzing the advantages and disadvantages of different sampling schemes given in the National Standard GB/T24356-2009. Under the circumstance of large lot size, the sampling inspection should be carried out lot by lot with the lot size less than 200 and the least lot number. Investigations on such procedure are made base on the probability distributions of two types of errors. Numerical results of type I error show that the whole lot inspection is equivalent to the sub-lot inspections sequence from the point of probability of positive null hypothesis. At the same time, experiment results of type Ⅱ error with the typical sampling scheme show that the conclusions of sampling inspection according to the requests of GB/T24356-2009 may be badly wrong under the situation of low percentage of defectiveness.

Precise point positioning (PPP) with ambiguity resolution (AR) has been proved to be an effective method to improve the positioning accuracy and shorten the convergence time, which plays an important role in geodetic and geodynamic applications. In this study, the performance achieved based on the BeiDou Navigation Satellite System (BDS-2 and BDS-3) joint PPP-AR with high rate data was considered and the validation of its application to seismic displacement and marine high-precision surveying was evaluated. First, the methods of uncalibrated phase delays (UPDs) estimation and PPP-AR were introduced. Next, the performance achieved based on BDS PPP-AR in both static and simulated real-time kinematic mode was evaluated with hourly data selected from 16 tracking stations over 3 days and data sampling rate of 1 s. After convergence, the positioning accuracies in the east, north, and up directions were 3.4 cm, 1.5 cm, and 5.5 cm, which were improved by 11.9%, 3.8% and 2.2% compared with the float solutions. Finally, a test of applying BDS PPP-AR to marine surveying was carried out with two hours data collected from two independent GNSS receivers installed on a boat sailing along the coast of Bohai Sea, China. The onboard two data set are processed in post-processing kinematic BDS PPP mode. The accuracies were improved from 2.4 cm, 3.5 cm and 4.0 cm to 2.2 cm, 3.1 cm and 3.1 cm in the east, north and up directions by ambiguity resolution, with improvements of 8.3%, 11.4% and 22.5% over the float solutions. The results validated the feasibility of the BDS PPP-AR for high-accuracy maritime applications.