Article
Geosciences, Multidisciplinary
Duygu Kiyan, Volker Rath, Mark R. Muller, Mohammednur D. Ture, James Hodgson
Summary: Over the past decade, Geological Survey Ireland has acquired airborne electromagnetic data for the Tellus project, and developed the open-source toolbox aempy to facilitate data interpretation and modeling. Implemented in Python, aempy is adaptable for specific educational and research objectives, allowing for 1-D inversion modeling with processed frequency-domain airborne electromagnetic data.
JOURNAL OF APPLIED GEOPHYSICS
(2022)
Article
Geochemistry & Geophysics
Dana E. Peterson, Carol A. Finn, Paul A. Bedrosian
Summary: Water-saturated, hydrothermally altered rocks weaken volcanic edifices, leading to increased risk of sector collapses and mass flows of unconsolidated debris. Airborne geophysical measurements can be used to identify hydrothermally altered areas at Iliamna Volcano and suggest its instability.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geochemistry & Geophysics
Alexander Prikhodko, Andrei Bagrianski, Petr Kuzmin, Aamna Sirohey
Summary: The mineral resources exploration industry has high efficiency requirements for geophysical technologies, and airborne electromagnetic technologies have been used for subsurface exploration due to their low cost and ability to rapidly acquire data over large areas. However, limitations on the depth of investigation and technical specifications of these systems hinder their application in certain geoelectrical conditions and geographical terrains. Methods utilizing natural electromagnetic fields in the audio frequency range have significantly increased the depth of investigation and sensitivity to a wide range of resistivity contrasts.
Article
Environmental Sciences
Wouter Deleersnyder, David Dudal, Thomas Hermans
Summary: This paper proposes an appraisal tool for evaluating the inconsistency between the inversion model and multidimensional data, using a normalized gradient calculated based on multidimensional forward modeling. Additionally, an alternative approach is suggested to account for imperfect forward modeling with low computational cost. The method is demonstrated on an AEM survey, revealing potential problematic zones in the estimated fresh-saltwater interface.
Article
Environmental Sciences
Jin Huang, Jantien Stoter, Ravi Peters, Liangliang Nan
Summary: This paper presents a fully automatic approach for reconstructing compact 3D building models from large-scale airborne point clouds. The approach addresses the challenge of missing vertical walls by inferring them directly from the data. The method outperforms state-of-the-art methods in terms of reconstruction accuracy and robustness, as demonstrated in experiments on various large-scale airborne LiDAR point clouds. Additionally, the authors have generated a new dataset with their method, which can stimulate research in urban reconstruction and the use of 3D city models in urban applications.
Article
Environmental Sciences
S. Kang, R. Knight, T. Greene, C. Buck, G. Fogg
Summary: This study utilized AEM data to acquire high-quality data, which were inverted and transformed to obtain sediment type models and estimates of sand/gravel content. Exploring the model space revealed the large-scale structure of the aquifer system, accurately capturing and communicating the uncertainty in sediment type.
WATER RESOURCES RESEARCH
(2021)
Article
Management
Evren Guney, Markus Leitner, Mario Ruthmair, Markus Sinnl
Summary: Influence maximization aims to identify key individuals in a network to maximize the number of individuals reached through information propagation. It can be modeled as a stochastic maximal covering location problem based on the probabilistic independent cascade model. Preprocessing tests and efficient algorithms for separating Benders cuts play crucial roles in the branch-and-cut algorithm.
EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
(2021)
Article
Water Resources
Chris Li, Rebecca Doble, Michael Hatch, Graham Heinson, Ben Kay
Summary: The study area in Kapunda, South Australia, was established as a mining town in 1842 and the open-pit mine was a key economic driver until its closure in 1879. The study focuses on the feasibility of recovering remnant copper using In-Situ Recovery techniques. A field trial involving lixiviant injection and extraction is under development, with modeling and geophysical techniques used to investigate flow paths and residence time of the injectant in the aquifer. The modeling suggests a low probability of injectant escape and a wide range of residence times, indicating the need for further study and consideration of injectant biodegradability.
JOURNAL OF HYDROLOGY-REGIONAL STUDIES
(2021)
Article
Engineering, Electrical & Electronic
Bruno Colonetti, Erlon Finardi, Samuel Brito, Victor Zavala
Summary: Unit commitment is a complex problem in power system operations that has yet to be fully solved. Operators currently use optimization solvers and simplifications to address the problem, but solving it in a timely manner remains a challenge. This study proposes a parallel dynamic integer programming approach for solving the unit commitment problem, which has been successfully applied to different power systems with impressive speed-ups compared to sequential strategies.
IEEE TRANSACTIONS ON POWER SYSTEMS
(2023)
Article
Management
Jian Zhang, Kelin Luo, Alexandre M. Florio, Tom Van Woensel
Summary: Dynamic vehicle routing problems with stochastic customer requests (DVRPSR) aim to maximize the number of served requests by dynamically routing vehicles. This study proposes knapsack-based linear models to accurately approximate the expected reward-to-go for any state of the stochastic system. The models are combined with optimal acceptance and assignment decision rules to derive efficient and high-performing online scheduling policies.
EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
(2023)
Article
Management
Jinkyu Lee, Sanghyeon Bae, Woo Chang Kim, Yongjae Lee
Summary: This paper proposes a stagewise decomposition algorithm called value function gradient learning (VFGL) for large-scale multistage stochastic convex programs. VFGL finds the parameter values that best fit the gradient of the value function within a given parametric family. Compared with other decomposition algorithms, VFGL has a fixed number of parameters, and it can learn the parameters by means of stochastic gradient descent, which makes it easily parallelized and efficient. Numerical examples show that VFGL generates high-quality solutions and is computationally efficient.
EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
(2023)
Article
Mathematics
Nadide Caglayan, Sule Itir Satoglu
Summary: Disaster management involves mitigating, preparing, responding, and recovering from disasters. A multi-objective stochastic programming model was developed in this study to minimize casualties and improve efficiency in disaster response.
Article
Computer Science, Interdisciplinary Applications
Jessica Derkacz Weihermann, Saulo Pomponet Oliveira, Yaoguo Li, Francisco Jose Fonseca Ferreira, Adalene Moreira Silva, Richard Fortin
Summary: The standard processing of airborne gamma-ray spectrometry data is helpful in various fields, but considerations of flight height and overlap area are crucial. Inversion algorithm can calculate concentration to address data errors, and a logarithmic barrier approach can prevent negative values. Testing shows that the inversion method is more consistent with survey data.
COMPUTERS & GEOSCIENCES
(2021)
Article
Environmental Sciences
Peng Bai, Giulio Vignoli, Thomas Mejer Hansen
Summary: The study demonstrates that while using 1D forward modelling in airborne electromagnetic surveys is more computationally efficient than 3D inversions, it is important to consider the modeling error which can lead to false features in the reconstructions. Incorporating this information into the inversion process improves target reconstructions and ensures correct reliability estimates.
Article
Water Resources
Ziv Moreno
Summary: This study found that the heterogeneous structure of soil significantly affects the calibration of hydro-electrical relations and may cause large errors when translating electrical measurements to hydraulic state variables. In addition, a stochastic inversion technique based on Approximated Bayesian Computation was proposed, which can determine the geostatistical parameters of the soil by calibrating hydro-electrical properties at a few different measurement scales.
ADVANCES IN WATER RESOURCES
(2022)