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As the number of satellites and amount of space debris in Low-Earth orbit (LEO) increase, high-precision orbit determination is crucial for ensuring the safe operation of spacecraft and maintaining space situational awareness. However, ground-based optical observations are constrained by limited arc-segment angular data and dynamic noise interference, and the traditional Extended Kalman Filter (EKF) struggles to meet the accuracy and robustness requirements in complex orbital environments. To address these challenges, this paper proposes a Bayesian Adaptive Extended Kalman Filter (BAEKF), which synergistically optimizes track determination through dynamic noise covariance adjustment and Bayesian a posteriori probability correction. Experiments demonstrate that the average root mean square error (RMSE) of BAEKF is reduced by 34.7% compared to the traditional EKF, effectively addressing EKF's accuracy and stability issues in nonlinear systems. The RMSE values of UKF, RBFNN, and GPR also show improvement, providing a reliable solution for high-precision orbital determination using optical observation.
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http://dx.doi.org/10.3390/s25082527 | DOI Listing |
Electromagn Biol Med
September 2025
Computer Science and Business Systems, Sri Krishna College of Engineering and Technology, Coimbatore, India.
Subject-independent emotion detection using EEG (Electroencephalography) using Vibrational Mode Decomposition and deep learning is made possible by the scarcity of labelled EEG datasets encompassing a variety of emotions. Labelled EEG data collection over a wide range of emotional states from a broad and varied population is challenging and resource-intensive. As a result, models trained on small or biased datasets may fail to generalize well to unknown individuals or emotional states, resulting in lower accuracy and robustness in real-world applications.
View Article and Find Full Text PDFInfect Genet Evol
September 2025
Next Generation Sequencing Unit, School of Biomedical Sciences, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa; Division of Virology, School of Pathology, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa. Electronic address: N
The sub-Saharan African region bears the highest burden of rotavirus-associated morbidity and mortality, with substantial genetic diversity observed in circulating strains despite vaccine introduction. The G8 genotype, originally predominant in bovine strains, has increasingly become prevalent in humans, suggesting a possible interface of animal-to-human transmission and highlighting its role in African strain diversity. In this study, we performed whole genome sequencing and evolutionary analysis of 21 archival G8P[4] strains collected through gastroenteritis surveillance in South Africa between 2009 and 2021 from children under five years of age.
View Article and Find Full Text PDFMed Teach
September 2025
NordSim, Center for Skills Training and Simulation, Aalborg University Hospital, Aalborg, Denmark.
Background: Assessing skills in simulated settings is resource-intensive and lacks validated metrics. Advances in AI offer the potential for automated competence assessment, addressing these limitations. This study aimed to develop and validate a machine learning AI model for automated evaluation during simulation-based thyroid ultrasound (US) training.
View Article and Find Full Text PDFEnviron Res
September 2025
Key Laboratory for Mechanics in Fluid Solid Coupling Systems, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100190, China.
The watersheds face increasing pressure from both human activities and natural factors, which exacerbate potential risks and pose significant challenges to integrated watershed management. This study developed an effective methodology to evaluate watershed sustainability and predict potential risks based on watershed resilience dynamics by combining catastrophe theory, adaptive cycle theory, and the Copula-Bayesian Network. Taking the Dahei River Basin (DRB) in China as a case study, we systematically evaluated the resilience dynamics, diagnosed risks, and tracked key driving factors to propose management strategies.
View Article and Find Full Text PDFLancet HIV
September 2025
Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA; Department of Health Metrics Sciences, School of Medicine, University of Washington, Seattle, WA, USA. Electronic address:
Background: Past cohort studies have examined mortality among children and young adolescents (aged 0-14 years) who have received antiretroviral therapy (ART), but no systematic reviews have been undertaken to synthesise these findings. Our study aims to provide the most comprehensive global estimates of paediatric mortality among children and adolescents receiving ART.
Methods: For this systematic review and meta-regression analysis, we searched PubMed and Embase from Jan 1, 1990 to July 31, 2024 for studies reporting mortality among children and young adolescents living with HIV who were on ART.