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Related papers: On the numerical overshoots of shock-capturing sch…

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This paper presents a numerical method to implement the parameter estimation method using response statistics that was recently formulated by the authors. The proposed approach formulates the parameter estimation problem of It\^o drift…

Numerical Analysis · Mathematics 2019-03-05 He Zhang , Xiantao Li , John Harlim

A new combined sub-filter scale turbulence and shock-capturing model is developed for high-order finite volume numerics, extending previous work to unstructured solvers. Block Spectral Stresses (BSS) method relies on the spectra of the…

Fluid Dynamics · Physics 2024-03-01 Matteo Ruggeri , Victor C. B. Sousa , Carlo Scalo

The Harten-Lax-van Leer with contact (HLLC) scheme is known to be plagued by various forms of numerical shock instabilities. In this paper, we propose a new framework for developing shock stable, contact and shear preserving approximate…

Computational Physics · Physics 2018-03-14 Simon Sangeeth , J. C Mandal

Nonlinear least squares data-fitting driven by physical process simulation is a classic and widely successful technique for the solution of inverse problems in science and engineering. Known as "Full Waveform Inversion" in application to…

Optimization and Control · Mathematics 2020-10-28 William W. Symes

Periodic surface structures are nowadays standard building blocks of optical devices. If such structures are illuminated by aperiodic time-harmonic incident waves as, e.g., Gaussian beams, the resulting surface scattering problem must be…

Numerical Analysis · Mathematics 2016-05-05 Armin Lechleiter , Ruming Zhang

In this paper we propose computationally efficient and robust methods for estimating the moment tensor and location of micro-seismic event(s) for large search volumes. Our contribution is two-fold. First, we propose a novel joint-complexity…

Geophysics · Physics 2013-09-11 Gregory Ely , Shuchin Aeron

This paper compares the HLLEM and HLL-CPS schemes for Euler equations and proposes improvements for all Mach number flows. Enhancements to the HLLEM scheme involve adding anti-diffusion terms in the face normal direction and modifying…

Numerical Analysis · Mathematics 2024-11-15 A. Gogoi , J. C. Mandal

In situations where a wide range of flow scales are involved, the nonlinear scheme used should be capable of both shock capturing and low-dissipation.Most of the existing WCNS schemes are too dissipative because the weights deviate from…

Computational Physics · Physics 2023-06-19 Xuan Liu , Yaobing Min , Jinsheng Cai , Yankai Ma , Zhenguo Yan

When a plane electromagnetic wave impinges upon a diffraction grating or other periodic structures, reflected and transmitted waves propagate away from the structure in different radiation channels. A diffraction anomaly occurs when the…

Computational Physics · Physics 2022-10-05 Zitao Mai , Ya Yan Lu

Cosmic rays (CRs) are frequently modeled as an additional fluid in hydrodynamic (HD) and magnetohydrodynamic (MHD) simulations of astrophysical flows. The standard CR two-fluid model is described in terms of three conservation laws…

High Energy Astrophysical Phenomena · Physics 2021-02-02 Siddhartha Gupta , Prateek Sharma , Andrea Mignone

Anomaly detection in multivariate time series is challenging as heterogeneous subsequence anomalies may occur. Reconstruction-based methods, which focus on learning normal patterns in the frequency domain to detect diverse abnormal…

Machine Learning · Computer Science 2025-05-09 Xingjian Wu , Xiangfei Qiu , Zhengyu Li , Yihang Wang , Jilin Hu , Chenjuan Guo , Hui Xiong , Bin Yang

The statistics obtained from turbulent flow simulations are generally uncertain due to finite time averaging. The techniques available in the literature to accurately estimate these uncertainties typically only work in an offline mode, that…

We shed new light on the \textit{smoothness} of optimization problems arising in prediction error parameter estimation of linear and nonlinear systems. We show that for regions of the parameter space where the model is not contractive, the…

Systems and Control · Computer Science 2020-08-10 Antônio H. Ribeiro , Koen Tiels , Jack Umenberger , Thomas B. Schön , Luis A. Aguirre

The physical processes involved in the advective-acoustic instability are investigated with 2D numerical simulations. Simple toy models, developped in a companion paper, are used to describe the coupling between acoustic and…

Astrophysics · Physics 2011-02-11 Jun'ichi Sato , Thierry Foglizzo , Sebastien Fromang

We analyze in this paper the performance of a newly developed globally convergent numerical method for a coefficient inverse problem for the case of multi-frequency experimental backscatter data associated to a single incident wave. These…

Numerical Analysis · Mathematics 2017-06-07 Dinh-Liem Nguyen , Michael V. Klibanov , Loc H. Nguyen , Aleksandr E. Kolesov , Michael A. Fiddy , Hui Liu

A new energy and enstrophy conserving scheme is evaluated using a suite of test cases over the global spherical domain or bounded domains. The evaluation is organized around a set of pre-defined properties: accuracy of individual opeartors,…

Numerical Analysis · Mathematics 2020-12-11 Qingshan Chen , Lili Ju , Roger Temam

Waveform inversion is theoretically a powerful tool to reconstruct subsurface structures, but a usually encountered problem is that accurate sources are very rare, causing the computation unstable and divergent. This challenging problem,…

Geophysics · Physics 2024-07-12 Han Yu

The recently proposed sequential distributed detector based on level-triggered sampling operates as simple as the decision fusion techniques and at the same time performs as well as the data fusion techniques. Hence, it is well suited for…

Applications · Statistics 2015-06-12 Yasin Yilmaz , Xiaodong Wang

A low diffusion version of the HLL-CPS scheme for resolving the shear layers and the flow features at low Mach numbers is presented here. The low diffusion HLL-CPS scheme is obtained by reconstructing the velocities at the cell interface…

Fluid Dynamics · Physics 2023-08-21 A. Gogoi , J. C. Mandal

Surface roughness is an important quantity to many engineering and precision manufacturing disciplines. In this paper we investigate the problem of estimating the root-mean-square roughness of a sample by passive linear optical methods. By…