Preprints
Filtering by Subject: Engineering
Speeding up PPP ambiguity resolution using triple-frequency GPS/BeiDou/Galileo/QZSS data
Published: 2019-08-29
Subjects: Aerospace Engineering, Civil and Environmental Engineering, Engineering, Navigation, Guidance, Control and Dynamics
Precise point positioning (PPP) has been suffering from slow convergences to ambiguity-fixed solutions. It is expected that this situation can be relieved or even resolved using triple-frequency GNSS data. We therefore attempt an approach where uncombined triple-frequency GPS/BeiDou/Galileo/QZSS (Quasi-zenith satellite system) data are injected into PPP, whereas their raw ambiguities are mapped [...]
Bluecap: A Geospatial Model to Assess Regional Economic-Viability for Mineral Resource Development
Published: 2019-08-29
Subjects: Engineering, Mining Engineering
Frontier mineral exploration is often exclusively focused on assessing geological potential without consideration for the economic viability of resource development. This strategy may overlook potentially prosperous zones for more geologically-favoured but financially-disadvantageous regions, or conversely, may introduce implicit biases against potential developments without due regard to [...]
Imbibition in porous media: correlations of displacement events with pore-throat geometry and the identification of a new type of pore snap-off
Published: 2019-08-23
Subjects: Chemical Engineering, Civil and Environmental Engineering, Complex Fluids, Dynamics and Dynamical Systems, Engineering, Engineering Science and Materials, Environmental Engineering, Materials Science and Engineering, Mechanics of Materials, Petroleum Engineering, Transport Phenomena
The displacement of a non-wetting fluid by a wetting fluid in porous media, called imbibition, is important in many natural and industrial processes. During imbibition, the wetting fluid invades the pore space through a series of competitions between piston-like displacement, film and corner flow, snap-off, pore bypassing and trapping. Our understanding of these fundamental pore-scale [...]
Cohesive-Zone Effects in Hydraulic Fracture Propagation
Published: 2019-08-22
Subjects: Earth Sciences, Engineering, Engineering Mechanics, Engineering Science and Materials, Environmental Sciences, Geophysics and Seismology, Oil, Gas, and Energy, Physical Sciences and Mathematics
Hydraulic fracture presents an interesting case of crack elasticity and fracture propagation non-linearly coupled to fluid flow. Hydraulic fracture (HF) is often modeled using the Linear Elastic Fracture Mechan- ics (LEFM), which assumes that the damaged zone associated with the rock breakage near the advancing fracture front is small compared to the lengthscales of other physical processes [...]
E&P Business Transformation: Reserves – Technology – Information {RTI} Strategy
Published: 2019-08-06
Subjects: Engineering, Other Engineering
Reserves (R)– make and break E&P companies. Its value and reliability are THE most valuable asset. The reserves hopper – evolution from Resources to Reserves needs maximum management focus all over. Management stage-gates to reserves maturity are necessary and sufficient for good governance. Technology (T)– is a wide array of methods providing variable assessment of reserves. KPI of [...]
Realistic and simplified models of plant and leaf area indices for a seasonally dry tropical forest
Published: 2019-08-06
Subjects: Civil and Environmental Engineering, Desert Ecology, Ecology and Evolutionary Biology, Engineering, Environmental Engineering, Forest Management, Forest Sciences, Life Sciences, Plant Sciences, Research Methods in Life Sciences
Leaf Area Index (LAI) models that consider all phenological stages have not been developed for the Caatinga, the largest seasonally dry tropical forest in South America. LAI models that are currently used show moderate to high covariance when compared to in situ data, but they often lack accuracy in the whole spectra of possible values and do not consider the impact that the stems and branches [...]
SediNet: A configurable deep learning model for mixed qualitative and quantitative optical granulometry
Published: 2019-07-31
Subjects: Civil and Environmental Engineering, Civil Engineering, Earth Sciences, Engineering, Geomorphology, Physical Sciences and Mathematics
I describe a configurable machine-learning framework to estimate a suite of continuous and categorical sedimentological properties from photographic imagery of sediment, and to exemplify how machine learning can be a powerful and flexible tool for automated quantitative and qualitative measurements from remotely sensed imagery. The model is tested on a large dataset consisting of 400 images and [...]
Analog forecasting of extreme-causing weather patterns using deep learning
Published: 2019-07-31
Subjects: Artificial Intelligence and Robotics, Atmospheric Sciences, Computational Engineering, Computer Sciences, Engineering, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Numerical weather prediction (NWP) models require ever-growing computing time/resources, but still, have difficulties with predicting weather extremes. Here we introduce a data-driven framework that is based on analog forecasting (prediction using past similar patterns) and employs a novel deep learning pattern-recognition technique (capsule neural networks, CapsNets) and impact-based [...]
Can barrier islands survive sea-level rise? Quantifying the relative role of tidal deltas and overwash deposition
Published: 2019-07-18
Subjects: Civil and Environmental Engineering, Civil Engineering, Earth Sciences, Engineering, Environmental Engineering, Geology, Geomorphology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Sedimentology
Accepted open-access publication available at: https://doi.org/10.1029/2019GL085524 Barrier island response to sea-level rise depends on their ability to transgress and move sediment onto and behind the barrier, either through flood-tidal delta deposition, or via overwash. Our understanding of these processes over decadal or longer timescales, however, is limited. Here we [...]
Lateral variability of shelf-edge, slope and basin-floor deposits, Santos Basin, offshore Brazil
Published: 2019-06-28
Subjects: Earth Sciences, Engineering, Geology, Physical Sciences and Mathematics, Sedimentology
Construction of continental margins is driven by sediment transported across the shelf to the shelf-edge, where it is reworked by wave-, tide- and river-influenced processes within deltas and flanking clastic shorelines. Stalling of continental margin progradation often results in degradation of the outer shelf to upper slope, with re-sedimentation to the lower slope and basin-floor via a range [...]
Snow Depth and Snow Water Equivalent Estimation in the Northwestern Himalayan Watershed using Spaceborne Polarimetric SAR Interferometry
Published: 2019-06-27
Subjects: Earth Sciences, Engineering, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Water Resource Management
Snow depth (SD) and Snow Water Equivalent (SWE) constitute essential physical properties of snow and find extensive usage in the hydrological modelling domain. However, the prominent impact of the hydrometeorological conditions and difficult terrain conditions inhibit accurate measurement of the SD and SWE— an ongoing research problem in the cryosphere paradigm. In this context, spaceborne [...]
Information-theoretic Portfolio Decision Model for Optimal Flood Management
Published: 2019-06-27
Subjects: Civil and Environmental Engineering, Civil Engineering, Computational Engineering, Earth Sciences, Engineering, Environmental Engineering, Environmental Health and Protection, Environmental Sciences, Geomorphology, Hydraulic Engineering, Hydrology, Life Sciences, Natural Resources and Conservation, Natural Resources Management and Policy, Operations Research, Systems Engineering and Industrial Engineering, Other Civil and Environmental Engineering, Other Engineering, Other Environmental Sciences, Other Physical Sciences and Mathematics, Physical Sciences and Mathematics, Probability, Risk Analysis, Statistics and Probability, Sustainability, Systems Engineering, Water Resource Management
The increasing impact of flooding urges more effective flood management strategies to guarantee sustainable ecosystem development. Recent catastrophes underline the importance of avoiding local flood management, but characterizing large scale basin wide approaches for systemic flood risk management. Here we introduce an information-theoretic Portfolio Decision Model (iPDM) for the optimization of [...]
Decentralized Flood Forecasting Using Deep Neural Networks
Published: 2019-06-22
Subjects: Civil and Environmental Engineering, Engineering, Environmental Engineering, Life Sciences, Other Life Sciences
Predicting flood for any location at times of extreme storms is a longstanding problem that has utmost importance in emergency management. Conventional methods that aim to predict water levels in streams use advanced hydrological models still lack of giving accurate forecasts everywhere. This study aims to explore artificial deep neural networks performance on flood prediction. While providing [...]
Global resource potential of seasonal pumped-storage
Published: 2019-06-20
Subjects: Civil and Environmental Engineering, Engineering, Geotechnical Engineering, Hydraulic Engineering
The risk of seasonal mismatches between electricity supply and demand is increasing due to expanded use of wind, solar and hydropower resources. Power system planners are thus in search of low-cost seasonal energy storage options. Seasonal Pumped-Storage (SPS) can provide short, medium and long-term energy storage at a relatively low-cost and provides co-benefits in the form of freshwater storage [...]
Optimizing Regional Climate Model Output for Hydro-Climate Applications in the Eastern Nile Basin
Published: 2019-06-18
Subjects: Civil and Environmental Engineering, Climate, Earth Sciences, Engineering, Hydrology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
This study focuses on the Eastern Nile (EN) Basin, most of whose water flows into the High Aswan Dam (HAD), Egypt. It is, therefore, crucial to have an accurate hydrological assessment overtime to plan water resource management in the area. With complex topography, it is important to capture most of the physics captured with the least bias in meteorological information. Weather Research and [...]