In comparison with the ITRF2000 model, the ITRF2005 model represents a significant improvement in solution generation, datum definition and realization. However, these improvements cause a frame difference between the...In comparison with the ITRF2000 model, the ITRF2005 model represents a significant improvement in solution generation, datum definition and realization. However, these improvements cause a frame difference between the ITRF2000 and ITRF2005 models, which may impact GNSS data processing. To quantify this im- pact, the differences of the GNSS results obtained using the two models, including station coordinates, base- line length and horizontal velocity field, were analyzed. After transformation, the differences in position were at the millimeter level, and the differences in baseline length were less than 1 ram. The differences in the hori- zontal velocity fields decreased with as the study area was reduced. For a large region, the differences in these value were less than 1 mm/a, with a systematic difference of approximately 2 degrees in direction, while for a medium-sized region, the differences in value and direction were not significant.展开更多
The velocities of tectonic plates derived from GNSS time series are regularly used as input data for geophysical models. However, as shown by numerous researches, the coordinates time series contain residual errors of...The velocities of tectonic plates derived from GNSS time series are regularly used as input data for geophysical models. However, as shown by numerous researches, the coordinates time series contain residual errors of a systematic nature, which can significantly affect the reliability of the obtained velocity estimates. This research shows that using non-classical error theory of measurement(NETM)for processing GNSS time series allows detecting the presence of weak, not removed from GNSS processing, sources of systematic errors. Based on the coordinate time series of selected permanent GNSS stations in Europe, we checked the empirical distributions of errors by the NETM on G. Jeffries’ recommendations and on the principles of the theory of hypothesis tests according to Pearson’s criterion. It is established that the obtained coordinates time series of GNSS-stations only partially confirm the hypothesis of their conformity to the normal Gaussian distribution law, and this may be the main reason for their unrepresentative classification. In the future, it is necessary to identify and take into account the causes of residual errors that distort the real distribution of the results of the GNSS time series.展开更多
基金supported by the Special Earthquake Research Project Granted by the China Earthquake Administration(201308009)
文摘In comparison with the ITRF2000 model, the ITRF2005 model represents a significant improvement in solution generation, datum definition and realization. However, these improvements cause a frame difference between the ITRF2000 and ITRF2005 models, which may impact GNSS data processing. To quantify this im- pact, the differences of the GNSS results obtained using the two models, including station coordinates, base- line length and horizontal velocity field, were analyzed. After transformation, the differences in position were at the millimeter level, and the differences in baseline length were less than 1 ram. The differences in the hori- zontal velocity fields decreased with as the study area was reduced. For a large region, the differences in these value were less than 1 mm/a, with a systematic difference of approximately 2 degrees in direction, while for a medium-sized region, the differences in value and direction were not significant.
文摘The velocities of tectonic plates derived from GNSS time series are regularly used as input data for geophysical models. However, as shown by numerous researches, the coordinates time series contain residual errors of a systematic nature, which can significantly affect the reliability of the obtained velocity estimates. This research shows that using non-classical error theory of measurement(NETM)for processing GNSS time series allows detecting the presence of weak, not removed from GNSS processing, sources of systematic errors. Based on the coordinate time series of selected permanent GNSS stations in Europe, we checked the empirical distributions of errors by the NETM on G. Jeffries’ recommendations and on the principles of the theory of hypothesis tests according to Pearson’s criterion. It is established that the obtained coordinates time series of GNSS-stations only partially confirm the hypothesis of their conformity to the normal Gaussian distribution law, and this may be the main reason for their unrepresentative classification. In the future, it is necessary to identify and take into account the causes of residual errors that distort the real distribution of the results of the GNSS time series.