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Physical Sciences and Mathematics Commons™
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- Keyword
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- Remote sensing (2)
- Ellipsoid Reference Survey (ERS) (1)
- GIS (1)
- GNSS antenna (1)
- GNSS receiver (1)
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- GRACE (1)
- GRACE satellite data (1)
- Groundwater (1)
- Hydrogeology (1)
- Hydrology Saudi Arabia (1)
- Lakes (1)
- Low-cost (1)
- Multipath (1)
- Nubian (1)
- PPP (1)
- Precipitation (1)
- RTK/PPK (1)
- SNR (1)
- Shallow groundwater (1)
- Spatial resolution (1)
- Statistical downscaling techniques (1)
- Statistical geology (1)
- Vertical accuracies (1)
Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
Response Of Deep Aquifers To Climate Variability, Karem Fathy Abdelgaber Abdelmohsen
Response Of Deep Aquifers To Climate Variability, Karem Fathy Abdelgaber Abdelmohsen
Dissertations
Our recent analysis of Temporal Gravity Recovery and Climate Experiment (GRACE) solutions over the largest aquifer system in Africa (the Nubian Sandstone Aquifer System: NSAS) revealed that while the response of deep aquifers to climatic variations remains a relatively slow process that takes thousands to tens of thousands of years, there is a much faster response in aquifers that are characterized by dense networks of faults, fractures and karst as is the case with the NSAS. This rapid groundwater flow, when it occurs, is detected as an increase in GRACETWS over areas downgradient and distant (hundreds of km) from …
Cost-Effective Gnss Hardware For High-Accuracy Surveys And Its Prospects For Post-Processed Kinematic (Ppk) And Precise Point Positioning (Ppp) Strategies, Johnson Olusegun Oguntuase
Cost-Effective Gnss Hardware For High-Accuracy Surveys And Its Prospects For Post-Processed Kinematic (Ppk) And Precise Point Positioning (Ppp) Strategies, Johnson Olusegun Oguntuase
Dissertations
This dissertation determines for the first time the vertical accuracy achievable with low-cost mass-market multi-frequency, multi-GNSS (LM3GNSS) receivers, and antennas in the context of Ellipsoid Reference Survey (ERS), usually employed in bathymetric operations aboard survey platforms. LM3GNSS receivers are relatively new in the market, and their emergence is driven by the automobile industry and several mass-market applications requiring location-based solutions at high accuracies. It is foreseeable that emerging hydrographic survey platforms such as autonomous surface vehicles, small unmanned aircraft, crowd-sourced bathymetric platforms, and offshore GNSS buoy will find LM3GNSS receivers attractive since they are power- and cost-effective (often less than …
Statistical Downscaling Techniques To Enhance The Spatial Resolution Of The Grace Satellite Data And To Fill Temporal Gaps, Hossein Sahour
Statistical Downscaling Techniques To Enhance The Spatial Resolution Of The Grace Satellite Data And To Fill Temporal Gaps, Hossein Sahour
Dissertations
The Gravity Recovery and Climate Experiment (GRACE) has been successfully used to monitor variations in terrestrial water storage (GRACETWS ) and groundwater storage (GRACEGWS) across the globe, yet such applications are hindered on local scales by the limited spatial resolution of GRACE data. Using the Lower Peninsula of Michigan as a test site, I developed optimum procedures to downscale GRACE Release-06 monthly mascon solutions. A four-fold exercise is conducted. Cluster analysis is performed to identify the optimum number and distribution of clusters (areas) of contiguous pixels of similar geophysical signals (GRACETWS time series); three clusters are …
An Integrated Approach (Remote Sensing, Hydrogeology, Gis, And Statistical Modeling) To Identify The Distribution Of Shallow Groundwater Occurrences Over Southwest Saudi Arabia, Fahad Khudier Alshehri
An Integrated Approach (Remote Sensing, Hydrogeology, Gis, And Statistical Modeling) To Identify The Distribution Of Shallow Groundwater Occurrences Over Southwest Saudi Arabia, Fahad Khudier Alshehri
Dissertations
Identifying shallow (near-surface) groundwater in arid and hyper-arid areas has significant societal benefits, yet it is a costly operation when traditional methods (geophysics and drilling) are applied over large domains. In this study, we developed and successfully applied methodologies that rely heavily on readily available temporal, visible and near-infrared, radar, and thermal remote sensing data sets and field data, as well as statistical approaches to map the distribution of shallow (1–5 m deep) groundwater occurrences in Al Qunfudah Province, Saudi Arabia and to identify the factors controlling their development. A four-fold approach was adopted: (1) constructing a digital database to …