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Developments in transcriptomics techniques have caused a large demand in tailored computational methods for modelling gene expression dynamics from experimental data. Recently, so-called single-cell experiments have revolutionised genetic…

Quantitative Methods · Quantitative Biology 2019-03-18 Atte Aalto , Jorge Goncalves

We describe a method to extract from experimental data the important dynamical modes in spatio-temporal patterns in a system driven out of thermodynamic equilibrium. Using a novel optical technique for controlling fluid flow, we create an…

Fluid Dynamics · Physics 2011-05-03 Adam C. Perkins , Roman O. Grigoriev , Michael F. Schatz

It was recently demonstrated that time-dependent PDE problems can numerically be solved with a fully pseudospectral scheme, i.e. using spectral expansions with respect to both spatial and time directions (Hennig and Ansorg, 2009 [15]). This…

General Relativity and Quantum Cosmology · Physics 2012-12-18 Jörg Hennig

Many successful methods to learn dynamical systems from data have recently been introduced. However, ensuring that the inferred dynamics preserve known constraints, such as conservation laws or restrictions on the allowed system states,…

Machine Learning · Computer Science 2024-02-16 Alistair White , Niki Kilbertus , Maximilian Gelbrecht , Niklas Boers

Many real-world systems exhibit ``noisy'' evolution in time; interpreting their finitely-sampled behavior as arising from continuous-time processes (in the It\^o or Stratonovich sense) has led to significant success in modeling and analysis…

Mathematical Physics · Physics 2025-07-29 David Sabin-Miller , Daniel M. Abrams

We present a comprehensive analysis of 21 light curves of Type 1 AGN from the Kepler spacecraft. First, we describe the necessity and development of a customized pipeline for treating Kepler data of stochastically variable sources like AGN.…

High Energy Astrophysical Phenomena · Physics 2018-06-27 Krista Lynne Smith , Richard F. Mushotzky , Patricia T. Boyd , Matt Malkan , Steve B. Howell , Dawn M. Gelino

Model atoms are an integral part in the solution of non-LTE problems. They comprise the atomic input data that are used to specify the statistical equilibrium equations and the opacities and emissivities of radiative transfer. A realistic…

Solar and Stellar Astrophysics · Physics 2015-03-17 Norbert Przybilla

We use strongly gravitationally lensed (SGL) systems to put additional constraints on a set of holographic dark energy models. Data available in the literature (redshift and velocity dispersion) is used to obtain the Einstein radius and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Victor H. Cardenas , Alexander Bonilla , Veronica Motta , Sergio del Campo

We analysed the light curves of a large sample of long period variables in the LMC from the AGAPEROS catalogue. The (non)regularity of the light change is discussed in detail showing that the majority of the light curves cannot be described…

Astrophysics · Physics 2009-11-07 T. Lebzelter , M. Schultheis , A. L. Melchior

In this paper we introduce the concept of Direct Statistical Simulation (DSS) for astrophysical flows. This technique may be appropriate for problems in astrophysical fluids where the instantaneous dynamics of the flows are of secondary…

Solar and Stellar Astrophysics · Physics 2011-01-17 S. M. Tobias , K. Dagon , J. B. Marston

Identifying the governing equations of a nonlinear dynamical system is key to both understanding the physical features of the system and constructing an accurate model of the dynamics that generalizes well beyond the available data. We…

Machine Learning · Computer Science 2022-08-16 Peter Y. Lu , Joan Ariño , Marin Soljačić

Fractional differential equations (FDEs) are an extension of the theory of fractional calculus. However, due to the difficulty in finding analytical solutions, there have not been extensive applications of FDEs until recent decades. With…

Numerical Analysis · Mathematics 2020-07-20 Nirupama Bhattacharya , Gabriel A. Silva

Many complex systems operating far from the equilibrium exhibit stochastic dynamics that can be described by a Langevin equation. Inferring Langevin equations from data can reveal how transient dynamics of such systems give rise to their…

Machine Learning · Statistics 2021-11-01 Mikhail Genkin , Owen Hughes , Tatiana A. Engel

Advances in data science are leading to new progresses in the analysis and understanding of complex dynamics for systems with experimental and observational data. With numerous physical phenomena exhibiting bursting, flights, hopping, and…

Statistics Theory · Mathematics 2022-02-09 Yang Li , Jinqiao Duan

The great learning ability of deep learning models facilitates us to comprehend the real physical world, making learning to simulate complicated particle systems a promising endeavour. However, the complex laws of the physical world pose…

Machine Learning · Computer Science 2025-08-26 Guangsi Shi , Daokun Zhang , Ming Jin , Shirui Pan , Philip S. Yu

Identifying dynamical systems from experimental data is a notably difficult task. Prior knowledge generally helps, but the extent of this knowledge varies with the application, and customized models are often needed. Neural ordinary…

Systems and Control · Electrical Eng. & Systems 2023-01-13 Mona Buisson-Fenet , Valery Morgenthaler , Sebastian Trimpe , Florent Di Meglio

The results of recent AGN monitoring campaigns confirm the ``big picture'' of the echo paradigm, but the details of the emission-line light curves cannot be accurately reproduced with only the simplest assumptions, some of which must be…

Astrophysics · Physics 2007-05-23 Dan Maoz

Neural Ordinary Differential Equations (NODEs) use a neural network to model the instantaneous rate of change in the state of a system. However, despite their apparent suitability for dynamics-governed time-series, NODEs present a few…

Machine Learning · Computer Science 2021-08-18 Alexander Norcliffe , Cristian Bodnar , Ben Day , Jacob Moss , Pietro Liò

The behavior of many dynamical systems follow complex, yet still unknown partial differential equations (PDEs). While several machine learning methods have been proposed to learn PDEs directly from data, previous methods are limited to…

Machine Learning · Computer Science 2021-02-01 Valerii Iakovlev , Markus Heinonen , Harri Lähdesmäki

One of the main features of interest in analysing the light curves of stars is the underlying periodic behaviour. The corresponding observations are a complex type of time series with unequally spaced time points and are sometimes…

Applications · Statistics 2022-11-21 Efthymia Derezea , Alfred Kume , Dirk Froebrich