Results 101 to 110 of about 3,045 (214)

Towards operational assimilation of surface‐sensitive microwave radiances over land at Environment and Climate Change Canada: Investigation of key factors using a 1D‐EnVar framework

Quarterly Journal of the Royal Meteorological Society, EarlyView.
The study evaluates five factors affecting the assimilation of surface‐sensitive Advanced Microwave Sounding Unit‐A (AMSU‐A) radiances over land, including the simultaneous estimation of surface emissivity and the standard set of state variables, to improve numerical weather prediction (NWP) at Environment and Climate Change Canada (ECCC).
Zheng Qi Wang, Mark Buehner, Yi Huang, Maziar Bani Shahabadi, Joël Bédard   +4 more
wiley   +1 more source

How consistently do ensemble prediction systems represent the growth of atmospheric uncertainty?

Quarterly Journal of the Royal Meteorological Society, EarlyView.
Spread‐based diagnostics calculated for 12 ensemble prediction systems are compared to understand the consistency with which they represent atmospheric uncertainty growth. Good correlation between all these systems is found in the extratropics for a lead time range from 48 hr to between 96 hr and 192 hr.
Douglas Wood, Suzanne Gray, John Methven, Mark Rodwell   +3 more
wiley   +1 more source

A structurally localized ensemble Kalman filtering approach

Quarterly Journal of the Royal Meteorological Society, EarlyView.
We derive an inherently localized ensemble Kalman filtering (EnKF) approach, avoiding the need for any auxiliary localization technique. The idea is to first use the variational Bayesian optimization to approximate the (continuous) state analysis probability density function (pdf) by a product of independent marginal pdfs corresponding to small ...
Boujemaa Ait‐El‐Fquih, Ibrahim Hoteit   +1 more
wiley   +1 more source

Iterated Invariant Extended Kalman Filter (IterIEKF)

IEEE Transactions on Automatic Control
We study the mathematical properties of the Invariant Extended Kalman Filter (IEKF) when iterating on the measurement update step, following the principles of the well-known Iterated Extended Kalman Filter. This iterative variant of the IEKF (IterIEKF) systematically improves its accuracy through Gauss-Newton-based relinearization, and exhibits ...
Sven Goffin, Axel Barrau, Silvère Bonnabel, Olivier Brüls, Pierre Sacré   +4 more
openaire   +2 more sources

The benefits of a hybrid‐3DEnVar data assimilation scheme for the convection‐permitting NWP model AROME–Austria

Quarterly Journal of the Royal Meteorological Society, EarlyView.
The climatological‐error covariance matrix used in three‐dimensional variational data assimilation (3DVar) provides smooth and isotropic increments spread to long distances. In contrast, three‐dimensional ensemble variational data assimilation (3DEnVar) with a purely ensemble‐error covariance matrix provides inhomogeneous increments and contains the ...
Kaushambi Jyoti, Philipp Griewank, Florian Meier, Martin Weissmann   +3 more
wiley   +1 more source

Impact of data assimilation on Arctic sea‐ice thickness variability and its coupling with atmospheric forcing

Quarterly Journal of the Royal Meteorological Society, EarlyView.
We document for the first time how the assimilation of CS2SMOS observations improves the model representation of Arctic sea‐ice thickness (SIT) and its variability: biases are reduced (top row), while excessive variability in the Beaufort Sea and lack of variability in the ice pack are both corrected (bottom row).
Jiping Xie, Yue Ying, Richard Davy, Laurent Bertino   +3 more
wiley   +1 more source

Initial State Privacy of Nonlinear Systems on Riemannian Manifolds

International Journal of Robust and Nonlinear Control, EarlyView.
ABSTRACT In this paper, we investigate initial state privacy protection for discrete‐time nonlinear closed systems. By capturing Riemannian geometric structures inherent in such privacy challenges, we refine the concept of differential privacy through the introduction of an initial state adjacency set based on Riemannian distances.
Le Liu, Yu Kawano, Antai Xie, Ming Cao
wiley   +1 more source

Control System for the Navigation of the Agricultural Robots: A Review

Journal of Field Robotics, EarlyView.
ABSTRACT Control systems for the navigation of autonomous agricultural robots—particularly those operating in uneven terrain and in the presence of static or dynamic obstacles—have advanced considerably in recent years. As conventional machinery evolves toward increasingly automated systems, the design of reliable navigation controllers has become ...
Edna Carolina Moriones Polanía, Hugo Rafacho Fernandes, Daniel Albiero, Angel Pontin Garcia   +3 more
wiley   +1 more source

Redefining Optimal Coverage Path Planning for FLS‐Equipped AUVs With Deep Reinforcement Learning

Journal of Field Robotics, EarlyView.
ABSTRACT Autonomous Underwater Vehicles (AUVs) have emerged as indispensable tools for a variety of subsea tasks, from habitat monitoring and seabed mapping to infrastructure inspection and mine countermeasures. A fundamental challenge in this field is Coverage Path Planning (CPP), the problem of ensuring complete and efficient area coverage.
Lorenzo Cecchi, Alberto Topini, Alessandro Bucci, Alessandro Ridolfi   +3 more
wiley   +1 more source

Biomimetic Multifinger Tactile Sensing and Contact‐Regulated Palpation for Autonomous Breast Tumor Localization

Journal of Field Robotics, EarlyView.
ABSTRACT Early detection of breast abnormalities remains challenging: manual palpation is subjective and operator‐dependent, while imaging modalities may miss small or subtle stiffness anomalies. This paper presents a biomimetic multifinger robotic palpation approach intended to support early breast‐cancer screening and follow‐up assessment as a proof ...
Kai Cheng, Yuanyuan Shen, Huanhai Zhang, Baifeng Li, Chao Cheng, Hamid Reza Karimi, Hang Su, Samer Alfayad   +7 more
wiley   +1 more source