An assessment of seasonal variations in the cref cors at the University of Lagos

• Autorzy: Nwilo Peter Chigozie , Ayodele Emmanuel Gbenga , Okolie Chukwuma John , Orji Michael Joseph , Marve Mnguhenen Funmilayo , Oyelade Esther Abidemi , Daramola Olagoke Emmanuel

Identyfikatory

DOI

10.15576/GLL/2020.1.63

• Języki publikacji: EN

Abstrakty

EN

Continuously Operating Reference Stations (CORS) are reference stations of the Global Navigation Satellite System (GNSS), providing fundamental positioning infrastructure that is accurate and reliable. As such, CORS are designed to meet the needs of a wide range of users requiring high three-dimensional (3D) positional accuracy. The Continuously Operating Reference Station at the Engineering Faculty (CREF), University of Lagos was set up in order to support research applications in Surveying, Mapping and Geodesy. This study evaluates the seasonal variations in the 3D coordinates of CREF using metrics such as coordinate differences, Standard Deviation (SD) and Standard Error (SE). The Canadian Spatial Reference System (CSRS), known as CSRS – Precise Point Positioning (CSRS-PPP) was used to compute the station’s daily coordinates over a three-year period from 2016 to 2018. In the analysis, the daily coordinates were divided into two seasons - the wet and the dry. The results obtained show that the dry and the wet seasons had SDs (5.4 mm, 3.9 mm, and 2.0 mm) and (5.2 mm, 18.6 mm and 14.4 mm) in the x, y and z-directions respectively. Generally, the dry season presents a better result than the wet season as revealed by the accuracy metrics. These results have led to an increased understanding of the seasonal variability inherent in the data acquired by GNSS CORS, and must be taken into consideration: in particular, for GNSS applications such as the weather prediction and water vapour estimation. This study concludes that more needs to be done regarding the maintenance of CREF to ensure data continuity and reliability for geodetic studies.

Słowa kluczowe

EN

GNSS; CORS; CREF; CSRS-PPP; seasonal variation

PL

GNSS; CORS; CREF; CSRS-PPP

• Wydawca: Wydawnictwo Uniwersytetu Rolniczego w Krakowie
• Czasopismo: Geomatics, Landmanagement and Landscape
• Rocznik: 2020
• Tom: no. 1
• Strony: 63--77
• Opis fizyczny: Bibliogr. 29 poz., rys., tab.

Twórcy

autor

Nwilo Peter Chigozie

• University of Lagos Department of Surveying and Geoinformatics Lagos, Nigeria

autor

Ayodele Emmanuel Gbenga

• University of Lagos Department of Surveying and Geoinformatics Lagos, Nigeria

autor

Okolie Chukwuma John

• University of Lagos Department of Surveying and Geoinformatics Lagos, Nigeria

autor

Orji Michael Joseph

• University of Lagos Department of Surveying and Geoinformatics Lagos, Nigeria

autor

Marve Mnguhenen Funmilayo

• University of Lagos Department of Surveying and Geoinformatics Lagos, Nigeria

autor

Oyelade Esther Abidemi

• University of Lagos Department of Surveying and Geoinformatics Lagos, Nigeria

autor

Daramola Olagoke Emmanuel

• University of Lagos Department of Surveying and Geoinformatics Lagos, Nigeria

Bibliografia

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Uwagi

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2020).