Article
Astronomy & Astrophysics
Y. Yokota, S. Watanabe, T. Ishikawa, Y. Nakamura
Summary: This paper investigates the temporal change of underwater gradient structure in GNSS-A observation and verifies the assumption that this change is not significant within several hours. The results show that maintaining this assumption can improve positioning accuracy, but there are also cases where the assumption is not valid. Therefore, studying the change of gradient structure during observation is important.
EARTH AND SPACE SCIENCE
(2022)
Article
Environmental Sciences
Karine Hagesaether Foss, Gunhild Elisabeth Berget, Jo Eidsvik
Summary: This article discusses the importance of embedding realistic statistical models in robotic sensor platforms for environmental monitoring and proposes myopic and hybrid strategies for autonomous underwater vehicle sampling. These strategies are based on a stochastic advection-diffusion Gaussian process model for mine tailings concentration in a Norwegian fjord. Simulation studies show that the suggested strategies outperform other approaches that simplify models or design criteria.
Article
Soil Science
Siegfried C. K. Hofman, D. J. Brus
Summary: This study utilized a geo-statistical simulation approach to predict the variance of mean NO3-N content in agricultural fields, revealing a large variation in NO3-N variance among the sixteen fields.
Article
Economics
Xinxin Yang, Xinghua Zheng, Jiaqi Chen
Summary: Tests for high-dimensional covariance matrices based on a generalized elliptical model are developed, without assuming specific parametric distributions or involving data kurtosis. These tests can be used to test uncorrelatedness among idiosyncratic returns, demonstrating their flexibility and applicability.
JOURNAL OF ECONOMETRICS
(2021)
Article
Statistics & Probability
Zhixiang Zhang, Shurong Zheng, Guangming Pan, Ping-Shou Zhong
Summary: We consider high-dimensional spiked sample covariance models and prove that the leading sample spiked eigenvalues and linear spectral statistics are asymptotically independent when the sample size and dimension are proportional. We also establish the central limit theorem of the leading sample spiked eigenvalues without assuming block diagonal structure on the population covariance matrix. Moreover, we propose consistent estimators for the L-4 norm of the spiked population eigenvectors. Based on these results, we develop a new statistic to test the equality of two spiked population covariance matrices, and numerical studies show its superiority over existing methods.
ANNALS OF STATISTICS
(2022)
Article
Engineering, Electrical & Electronic
Jun Su, Yaan Li, Wasiq Ali
Summary: This paper improves the 3D constant turn (3D-CT) model for underwater target motion and proposes a novel interacting multiple model underwater Gauss-Helmert unscented Kalman filter (IMM-UGHUKF) to address the challenging problems in traditional tracking.
IET RADAR SONAR AND NAVIGATION
(2022)
Article
Engineering, Electrical & Electronic
Haoqian Huang, Jiacheng Tang, Cong Liu, Bo Zhang, Bing Wang
Summary: A novel variational Bayesian-based filter for inaccurate input (VBFII) is proposed to determine the state information of autonomous underwater vehicle (AUV) under the complex marine condition. The algorithm assumes velocities follow Gaussian distribution and utilizes augmentation method for simplification, resulting in better estimation accuracy and robustness compared to other algorithms according to experiment results.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Peng Gu, Zhongliang Jing, Liangbin Wu
Summary: A robust adaptive probability hypothesis density (PHD) filter is proposed in this paper to address the degradation of PHD performance due to an unknown process noise and measurement noise covariance matrix. The introduced inverse Wishart distribution is used to model the prior distribution of process noise and measurement noise, and the multi-target posterior intensity is approximated as a mixture of inverse Wishart distribution and Gaussian distribution. The closed solution of the robust PHD filter is derived using the variational Bayes approach, and simulation results show its superior performance compared to existing methods.
IET RADAR SONAR AND NAVIGATION
(2022)
Article
Statistics & Probability
Zhendong Wang, Xingzhong Xu
Summary: With the emergence of the big data era, testing high dimensional covariance matrices has become a prominent area in contemporary statistical inference. A novel test based on posterior Bayes factor is proposed in this paper for the identification and sphericity testing. The research shows that the new test outperforms some well-known tests in terms of Type I error rate and empirical power under general alternatives.
JOURNAL OF MULTIVARIATE ANALYSIS
(2021)
Article
Mathematics
Vadim Gorin, Yi Sun
Summary: This article studies the global fluctuations of singular values of multiple random matrix ensembles, showing that as the size of the matrix tends to infinity, the fluctuations of their height functions converge to a specific Gaussian field. The study focuses on the multivariate Bessel generating functions of the spectral measures, proving a central limit theorem for global fluctuations.
AMERICAN JOURNAL OF MATHEMATICS
(2022)
Article
Statistics & Probability
Yiting Li, Kevin Schnelli, Yuanyuan Xu
Summary: The study proves a universal Central Limit Theorem for the linear eigenvalue statistics of N by N deformed Wigner random matrices, including at both spectral bulk and regular edges where the global eigenvalue density vanishes. Additionally, analogous results are shown for high-dimensional sample covariance matrices.
ANNALES DE L INSTITUT HENRI POINCARE-PROBABILITES ET STATISTIQUES
(2021)
Article
Engineering, Chemical
Philipp Seufert, Jan Schwientek, Michael Bortz
Summary: This study presents a novel design of experiments algorithm that computes optimal designs in a continuous design space based on the Kiefer-Wolfowitz Equivalence Theorem. By combining an adaptive Bayes-like sampling scheme with Gaussian process regression, the algorithm approximates the directional derivative of the design criterion and adaptively selects new design points, reducing evaluations of the Jacobian matrix and computation runtime in two chemical engineering examples.
Article
Engineering, Electrical & Electronic
Wence Shi, Jiangning Xu, Ding Li, Hongyang He
Summary: This paper proposes an improved Kalman filter (VBRAKF) that effectively solves the attitude estimation problem in a complex underwater environment. The filter achieves robustness by suppressing outliers based on Mahalanobis distance and adaptivity by estimating the uncertain measurement noise covariance using variational Bayesian approximation. Experimental results demonstrate the superiority of the proposed method over traditional methods.
IEEE SENSORS JOURNAL
(2022)
Article
Engineering, Electrical & Electronic
Chenhao Li, Simon Godsill
Summary: The non-homogeneous Poisson process allows the intensity of point generation to vary across time or space domains, with applications in signal processing and machine learning but limited by intractable likelihood function and computationally efficient inference schemes. This paper proposes a framework that combines non-homogeneous Poisson model with continuous-time state-space models for efficient online inference. The proposed approach shows improved performance and computational efficiency compared to batch-based competitor algorithm and a simple baseline kernel estimation scheme.
IEEE TRANSACTIONS ON SIGNAL PROCESSING
(2021)
Article
Engineering, Electrical & Electronic
Xiangxiang Dong, Luigi Chisci, Yunze Cai
Summary: This paper proposes an improved adaptive variational Bayesian cubature information fusion algorithm for nonlinear multisensor systems with uncertain noise statistics. The algorithm jointly estimates system states and uncertain noise covariances, and outperforms conventional cubature Kalman/information filters according to simulation results.
Article
Geochemistry & Geophysics
Roberto Benavente, Jan Dettmer, Phil R. Cummins, Malcolm Sambridge
GEOPHYSICAL JOURNAL INTERNATIONAL
(2019)
Article
Engineering, Civil
Josee Belcourt, Charles W. Holland, Stan E. Dosso, Jan Dettmer, John A. Goff
IEEE JOURNAL OF OCEANIC ENGINEERING
(2020)
Article
Engineering, Civil
Josee Belcourt, Stan E. Dosso, Charles W. Holland, Jan Dettmer
IEEE JOURNAL OF OCEANIC ENGINEERING
(2020)
Article
Geochemistry & Geophysics
Charles W. Holland, Jan Dettmer, Gavin Steininger, Stan E. Dosso, Allen Lowrie
NEAR SURFACE GEOPHYSICS
(2020)
Editorial Material
Geochemistry & Geophysics
Hannes Vasyura-Bathke, Jan Dettmer, Andreas Steinberg, Sebastian Heimann, Marius Paul Isken, Olaf Zielke, Paul Martin Mai, Henriette Sudhaus, Sigurjon Jonsson
SEISMOLOGICAL RESEARCH LETTERS
(2020)
Article
Geochemistry & Geophysics
L. DiCaprio, T. Maiti, J. Dettmer, D. W. Eaton
Article
Geosciences, Multidisciplinary
Carlos Herrera, John F. Cassidy, Stan E. Dosso, Jan Dettmer, Wasja Bloch, Christian Sippl, Pablo Salazar
Summary: The study reveals the spatial variability of crustal stress in northern Chile, showing a margin-parallel compressive stress regime along the coast and a strike-slip faulting regime in the Andean Precordillera. The results suggest a connection between these stress regimes and seismic events.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geochemistry & Geophysics
Joshua C. S. Purba, Hersh Gilbert, Jan Dettmer
Summary: This study assesses seismicity in the southern Rocky Mountain trench through a temporary network of seismometers, identifying active structures and changes in earthquake distribution and style of deformation. It provides insights into the geometry of subsurface faults and their activity level with a catalog of 47 earthquakes, including horizontal and vertical uncertainty quantification. The seismicity observed suggests a transition from transpression to normal faulting along the length of the trench, with repeating events possibly linked to fluid migration.
SEISMOLOGICAL RESEARCH LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Surya Pachhai, Mingming Li, Michael S. Thorne, Jan Dettmer, Hrvoje Tkalcic
Summary: Studies reveal that ultralow-velocity zones beneath the Coral Sea exhibit stratified density increases and shear-wave velocity decreases, which may be related to remnants of Earth's early differentiation.
Article
Geochemistry & Geophysics
Sara Klaasen, Patrick Paitz, Nadja Lindner, Jan Dettmer, Andreas Fichtner
Summary: This study demonstrates the logistic feasibility and scientific potential of using distributed acoustic sensing (DAS) in challenging environments like the Mount Meager alpine volcano-glacial region, detecting unexpected seismic activity and developing a beamforming algorithm based on signal-to-noise ratios.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geochemistry & Geophysics
Wenyong Pan, Luping Qu, Kristopher A. Innanen, Jan Dettmer, Marie Macquet, Donald Lawton, Yanfei Wang
Summary: Distributed acoustic sensing (DAS) technology is widely evaluated as a cost-effective and nonintrusive seismic monitoring tool for CO2 sequestration. Optical fibers deployed in surface trenches can record high-quality surface waves, and full-waveform inversion (FWI) is applied to image the S-wave velocity (VS) and attenuation (quality factor QS) models. The low-frequency components in DAS recordings help overcome FWI's cycle-skipping problem. The inversion results provide valuable information for characterizing near-surface environments and support seismic imaging in deeper CO2 injection zones.
Article
Geochemistry & Geophysics
Carlos Herrera, John F. Cassidy, Jan Dettmer, Efrain Rivera, Sergio Ruiz, Hannes Vasyura-Bathke
Summary: On September 10, 2008, a M-w 5.7 earthquake occurred in the Central Valley of northern Chile near the town of Pica. The earthquake had a high stress-drop and generated unusually high ground accelerations. The source properties indicate reverse-oblique fault motion on a plane dipping to the northeast, consistent with the dominant style of faulting in the region. Despite the lower occurrence rate of crustal events compared to interplate and inslab events, similar or larger magnitude crustal events have occurred approximately once every three years in northern Chile, posing a significant hazard to nearby populations or critical infrastructure.
SEISMOLOGICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
S. H. McKean, J. A. Priest, J. Dettmer, G. Fradelizio, D. Eaton
Summary: A Bayesian quantile regression method is used to separate microseismic events related to hydraulic fractures from induced events. This method allows for optimization of hydraulic treatments and mitigation of induced seismicity. A case study demonstrates the successful differentiation of faults connected to hydraulic fractures and faults solely related to induced seismicity.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Environmental Sciences
Hannes Vasyura-Bathke, Jan Dettmer, Katherine Biegel, Rebecca O. Salvage, David Eaton, Nicolas Ackerley, Sergey Samsonov, Torsten Dahm
Summary: A joint analysis of InSAR and seismic data reveals that long-term saltwater disposal in western Canada triggers resurgent earthquakes by reactivating a complex fault system. The mainshock of the earthquake sequence occurred at a depth of about 5 km and propagated towards the injection source, stopping at a depth of about 2 km. The reactivated faults are part of a regional, basement-rooted graben system and appear to be truncated by a fault that is misoriented for slip in the present-day stress regime.
COMMUNICATIONS EARTH & ENVIRONMENT
(2023)
Article
Environmental Sciences
Susanne M. M. Ouellet, Jan Dettmer, Gerrit Olivier, Tjaart DeWit, Matthew Lato
Summary: In this study, ambient noise interferometry is used to monitor the performance of a tailings dam and is correlated with water level changes. A one-dimensional model is obtained, showing good results. This method provides important advances and implications for understanding changes in dam performance by directly measuring soil stiffness and inferring other geotechnical design parameters.
COMMUNICATIONS EARTH & ENVIRONMENT
(2022)