We present general methodology for sequential inference in nonlinear stochastic state-space models to simultaneously estimate dynamic states and fixed parameters. We show that basic particle filters may fail due to degeneracy in fixed parameter estimation and suggest the use of a kernel density approximation to the filtered distribution of the fixed parameters to allow the fixed parameters to regenerate. In addition, we show that "seemingly" uninformative uniform priors on fixed parameters can affect posterior inferences and suggest the use of priors bounded only by the support of the parameter. We show the negative impact of using multinomial resampling and suggest the use of either stratified or residual resampling within the particle filter. As a motivating example, we use a model for tracking and prediction of a disease outbreak via a syndromic surveillance system. Finally, we use this improved particle filtering methodology to relax prior assumptions on model parameters yet still provide reasonable estimates for model parameters and disease states.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.mbs.2014.06.018 | DOI Listing |
Front Med (Lausanne)
December 2024
Department of Cardiology, The University-Town Hospital of Chongqing Medical University, Chongqing, China.
Purpose: To systematically evaluate the clinical efficacy and safety of targeted drugs in patients with pulmonary arterial hypertension (PAH) with cardiac function grades III-IV, and conduct a meta-analysis.
Methods: Two researchers independently searched the PubMed, EMBASE, and Cochrane Library databases for relevant studies, with the search period extending from the establishment of the databases to March 2024. Meta-analysis was performed using statistical software Review Manager 5.
Heliyon
December 2024
Department of Maritime Engineering, Amirkabir University of Technology, No. 424, Hafez Avenue, Tehran, 15916-34311, Iran.
In addition to the usual loads, fixed jacket offshore platforms can be exposed to accidental loads from ship collisions. Indentation of tubular components is a significant defect that occurs when a supply vessel collides with a jacket platform, which can affect the ultimate strength of the offshore platform. This paper performs a nonlinear dynamic analysis using ABAQUS software to evaluate the ultimate strength of a wellhead jacket platform and to investigate its structural response to two consecutive impacts from a 2700-ton ship.
View Article and Find Full Text PDFJ Cytol
November 2024
Department of Physiotherapy, University Institute of Allied Health Sciences, Chandigarh University, Mohali, Punjab, India.
Background: Liquid-based cytology (LBC) is a newer method of preparing cervical cell samples. This technique involves collecting cells in a liquid fixative and preparing and evaluating them.
Aim: This study aims to investigate cervical smears prepared using the Ezi-Prep LBC method and analyze the positivity rate for cervical cancer and assess the diagnostic accuracy of LBC in detecting cervical abnormalities among females with abnormal vaginal conditions attending a tertiary care center.
Chem Mater
December 2024
Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States.
Solid polymer electrolytes have yet to achieve the desired ionic conductivity (>1 mS/cm) near room temperature required for many applications. This target implies the need to reduce the effective energy barriers for ion transport in polymer electrolytes to around 20 kJ/mol. In this work, we combine information extracted from existing experimental results with theoretical calculations to provide insights into ion transport in single-ion conductors (SICs) with a focus on lithium ion SICs.
View Article and Find Full Text PDFSci Rep
December 2024
CETC POTEVIO SCIENCE & TECHNOLOGY CO., LTD, Guangzhou, 510310, P.R. China.
In recent years, the hydroacoustic communication MAC (Medium Access Control) protocol has attracted wide attention. Hydroacoustic communication networks suffer from issues such as long propagation delays and rapid dynamic changes in network load, which prevent the maximization of network performance through the use of a single transmission mode. In this paper, we propose a Dynamic Switching Transmission MAC protocol called the DSTM-MAC protocol.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!