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Related papers: Topological Approach for Data Assimilation

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We study different approaches to implementing sparse-in-time observations into the the Azouani-Olson-Titi data assimilation algorithm. We propose a new method which introduces a "data assimilation window" separate from the observational…

Analysis of PDEs · Mathematics 2023-03-08 Adam Larios , Yuan Pei , Collin Victor

In this paper, we develop topological data analysis methods for classification tasks on univariate time series. As an application, we perform binary and ternary classification tasks on two public datasets that consist of physiological…

Machine Learning · Statistics 2021-06-15 Alperen Karan , Atabey Kaygun

Accurate interpolation of seismic data is crucial for improving the quality of imaging and interpretation. In recent years, deep learning models such as U-Net and generative adversarial networks have been widely applied to seismic data…

Learning unnormalized statistical models (e.g., energy-based models) is computationally challenging due to the complexity of handling the partition function. To eschew this complexity, noise-contrastive estimation~(NCE) has been proposed by…

Machine Learning · Computer Science 2023-06-14 Wei Jiang , Jiayu Qin , Lingyu Wu , Changyou Chen , Tianbao Yang , Lijun Zhang

Topological Data Analysis (TDA) is an emergent field that aims to discover topological information hidden in a dataset. TDA tools have been commonly used to create filters and topological descriptors to improve Machine Learning (ML)…

Machine Learning · Computer Science 2022-02-07 Rolando Kindelan , José Frías , Mauricio Cerda , Nancy Hitschfeld

We study the problem of identifying the dynamics of a linear system when one has access to samples generated by a similar (but not identical) system, in addition to data from the true system. We use a weighted least squares approach and…

Systems and Control · Electrical Eng. & Systems 2022-04-13 Lei Xin , Lintao Ye , George Chiu , Shreyas Sundaram

Traditionally, computation of Lyapunov exponents has been the marque method for identifying chaos in a time series. Recently, new methods have emerged for systems with both known and unknown models to produce a definitive 0--1 diagnostic.…

Chaotic Dynamics · Physics 2020-03-03 Joshua R. Tempelman , Firas A. Khasawneh

We propose TopDis (Topological Disentanglement), a method for learning disentangled representations via adding a multi-scale topological loss term. Disentanglement is a crucial property of data representations substantial for the…

Machine Learning · Computer Science 2025-03-17 Nikita Balabin , Daria Voronkova , Ilya Trofimov , Evgeny Burnaev , Serguei Barannikov

Topological data analysis has recently been applied to the study of dynamic networks. In this context, an algorithm was introduced and helps, among other things, to detect early warning signals of abnormal changes in the dynamic network…

Algebraic Topology · Mathematics 2022-10-18 Bouchaib Azamir , Driss Bennis , Bertrand Michel

Discovering the underlying dynamics of complex systems from data is an important practical topic. Constrained optimization algorithms are widely utilized and lead to many successes. Yet, such purely data-driven methods may bring about…

Dynamical Systems · Mathematics 2023-05-17 Nan Chen , Yinling Zhang

The paper introduces a novel topological method for prediction and modeling for a nonlinear time--series that exhibit recurring patterns. According to the model, global manifold of the reconstructed state--space can be approximated by a few…

Chaotic Dynamics · Physics 2017-11-21 Sajini Anand P S , Prabhakar G Vaidya

This work addresses inverse linear optimization where the goal is to infer the unknown cost vector of a linear program. Specifically, we consider the data-driven setting in which the available data are noisy observations of optimal…

Optimization and Control · Mathematics 2021-12-07 Rishabh Gupta , Qi Zhang

This paper presents new dynamic topology adaptation strategies for distributed estimation in smart grids systems. We propose a dynamic exhaustive search--based topology adaptation algorithm and a dynamic sparsity--inspired topology…

Information Theory · Computer Science 2014-01-16 S. Xu , R. C. de Lamare , H. V. Poor

This chapter describes a novel approach for the treatment of model error in geophysical data assimilation. In this method, model error is treated as a deterministic process fully correlated in time. This allows for the derivation of the…

Atmospheric and Oceanic Physics · Physics 2015-11-11 Alberto Carrassi , Stéphane Vannitsem

Data Assimilation (DA) is a computational tool that uses value from the model and the real measurement to arrive to an optimally acceptable value. Rather, this technique relies on the idea of Kalman gain. We point out that DA has two…

Optimization and Control · Mathematics 2020-12-15 Mohammad N. Murshed , Zarin Subah , M. Monir Uddin

Unsupervised feature learning often finds low-dimensional embeddings that capture the structure of complex data. For tasks for which prior expert topological knowledge is available, incorporating this into the learned representation may…

Machine Learning · Computer Science 2022-03-08 Robin Vandaele , Bo Kang , Jefrey Lijffijt , Tijl De Bie , Yvan Saeys

Data assimilation (DA) integrates observations with a dynamical model to estimate states of PDE-governed systems. Model-driven methods (e.g., Kalman, particle) presuppose full knowledge of the true dynamics, which is not always satisfied in…

Signal Processing · Electrical Eng. & Systems 2025-06-06 Siyi Chen , Yixuan Jia , Qing Qu , He Sun , Jeffrey A Fessler

Understanding time-dependent blood flow dynamics in arteries is crucial for diagnosing and treating cardiovascular diseases. However, accurately predicting time-varying flow patterns requires integrating observational data with…

Fluid Dynamics · Physics 2025-01-09 Muhammad Adnan Anwar , Jorge Tiago

We propose a new numerical scheme for approximating level-sets of Lipschitz multivariate functions which is robust to stochastic noise. The algorithm's main feature is an adaptive grid-based stochastic approximation strategy which…

Numerical Analysis · Mathematics 2025-09-19 Matteo Croci , Abdul-Lateef Haji-Ali , Ian C. J. Powell

Topological data analysis provides a set of tools to uncover low-dimensional structure in noisy point clouds. Prominent amongst the tools is persistence homology, which summarizes birth-death times of homological features using data objects…

Methodology · Statistics 2024-02-05 James Matuk , Sebastian Kurtek , Karthik Bharath