Results 21 to 30 of about 122,694 (252)

A Data Quality Assessment Approach for High-Precision GNSS Continuously Operating Reference Stations (CORS) with Case Studies in Hong Kong and Canada/USA

Remote Sensing, 2023
Centimeter-level or better positioning accuracy is needed in engineering surveying applications. When employing the Global Navigation Satellite System (GNSS) in engineering surveying, the high-precision real-time kinematic (RTK) positioning method must ...
Lawrence Lau, Kai-Wing Tai
doaj   +1 more source

On the construction of gravimetric geoid model on the Lviv region area

Геофизический журнал, 2022
Baltic Height System 1977, currently used in Ukraine, the starting point of which is the zero of the Kronstadttide-gauge, isobsoletedue to the great distance from the zero-point of the reference height and the difficulty of adapting satellite methods of
F. Zablotskyi, V. Maksymchuk, B. Dzhuman   +2 more
doaj   +1 more source

Towards a vertical datum standardisation under the umbrella of Global Geodetic Observing System

Journal of Geodetic Science, 2012
Most of the existing height systems refer to local sea surface levels, are stationary (do not consider variations in time), and realise different physical height types (orthometric, normal, normal-orthometric, etc.).
Sánchez L.
doaj   +1 more source

Global Comparison of F2-Layer Peak Parameters Estimated by IRI-2016 With Ionospheric Radio Occultation Data During Solar Minimum

IEEE Access, 2021
The F2-layer peak parameters of the International Reference Ionosphere (IRI) model are critical to its subsequent applications because of the vital role of the peak parameters in determining other IRI model outputs. Therefore, we analyzed the statistical
Weihua Bai, Guangyuan Tan, Yueqiang Sun, Junming Xia, Qifei Du, Guanglin Yang, Xiangguang Meng, Danyang Zhao, Congliang Liu, Yuerong Cai, Dongwei Wang, Cong Yin, Peng Hu   +12 more
doaj   +1 more source

Efforts for aligning the Brazilian Height System to the International Height Reference System

, 2018
The International Height Reference System (IHRS) consolidated the idea of a world height system (WHS) according to the IAG Resolution 1/2015. Since 2000, the majority of activities related to the modernization of the Brazilian Height System (BHS) has referred to a physical meaning for the heights and have linked two existing vertical datums in the ...
Freitas, Sílvio R. C. de, Ferreira, Vagner G., Luz, Roberto T.   +2 more
openaire   +3 more sources

Geodetic Reference Systems and Map Projections in Bulgaria: Historical Context and Modern Applications [PDF]

Micro, Macro & Mezzo Geoinformation
The significant advancements in modern geodetic technologies over recent decades necessitate a reassessment of geodetic coordinate systems. These systems should enhance 3D positioning accuracy, provide direct access to the national reference geodetic ...
Lyubka Pashova
doaj   +1 more source

VLBI TRF Combination Using GNSS Software [PDF]

Journal of Astronomy and Space Sciences, 2013
Space geodetic techniques can be used to obtain precise shape and rotation information of the Earth. To achieve this, the representative combination solution of each space geodetic technique has to be produced, and then those solutions need to be ...
Younghee Kwak, Jungho Cho
doaj   +1 more source

Prevalence of overweight and obesity among saudi children: A comparison of two widely used international standards and the national growth references

Frontiers in Endocrinology, 2022
ObjectiveTo compare three body mass index (BMI) classifications that are used to assess the prevalence of overweight and obesity among Saudi children aged 6–13 years: the International Obesity Task Force (IOTF) age and gender cutoffs, the World Health ...
Hazzaa M. Al-Hazzaa, Amani A. Alrasheedi, Rayan A. Alsulaimani, Laura Jabri, Abdulrahman M. Alhowikan, Maha H. Alhussain, Rowaedh A. Bawaked, Saleh A. Alqahtani, Saleh A. Alqahtani   +8 more
doaj   +1 more source

Towards the unification of the Polish vertical reference frame with the International Height Reference System

, 2023
The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)
Marjanska, D., Walo, J., Olszak, T.
openaire   +2 more sources

Height Variation Depending on the Source of Antenna Phase Centre Corrections: LEIAR25.R3 Case Study

Sensors, 2019
In this study, we compared two sets of antenna phase center corrections for groups of the same type of antenna mounted at the continuously operating global navigation satellite system (GNSS) reference stations.
Andrzej Araszkiewicz, Damian Kiliszek, Anna Podkowa   +2 more
doaj   +1 more source