English
Related papers

Related papers: Cycle-skipping mitigation using misfit measurement…

200 papers

We introduce a `double-difference' method for the inversion for seismic wavespeed structure based on adjoint tomography. Differences between seismic observations and model predictions at individual stations may arise from factors other than…

Geophysics · Physics 2016-07-08 Yanhua O. Yuan , Frederik J. Simons , Jeroen Tromp

A simple inverse problem for the wave equation requires determination of both the wave velocity in a homogenous acoustic material and the transient waveform of an isotropic point radiator, given the time history of the wavefield at a remote…

Optimization and Control · Mathematics 2022-09-28 William W. Symes

Full-waveform inversion (FWI) is an advanced technique for reconstructing high-resolution subsurface physical parameters by progressively minimizing the discrepancy between observed and predicted seismic data. However, conventional FWI…

Geophysics · Physics 2025-03-04 Chao Song , Tariq Alkhalifah , Umair Bin Waheed , Silin Wang , Cai Liu

Adaptive Waveform Inversion (AWI) applied to transient transmitted wave data can yield estimates of index of refraction (or wave velocity) similar to those obtained by travel time inversion. The AWI objective function measures normalized…

Optimization and Control · Mathematics 2024-12-12 William W. Symes

This paper addresses the problem of multi-step time series forecasting for non-stationary signals that can present sudden changes. Current state-of-the-art deep learning forecasting methods, often trained with variants of the MSE, lack the…

Machine Learning · Statistics 2022-02-18 Vincent Le Guen , Nicolas Thome

We propose and test the Direct Waveform Inversion (DWI) scheme to simultaneously invert for layered velocity and density profiles, using reflection seismic waveforms recorded on the surface. The recorded data include primary reflections and…

Geophysics · Physics 2021-08-10 Zhonghan Liu , Yingcai Zheng , Hua-Wei Zhou

Seismology has been an active science for a long time. It changed character about 50 years ago when the earth's vibrations could be measured on the surface more accurately and more frequently in space and time. The full wave field could be…

Numerical Analysis · Mathematics 2018-08-15 Björn Engquist , Yunan Yang

Given set of functions $y_i(t)$ and $x(t)$ such that $y_i(t) = a_i x\left[h_i(t)\right]$ with $a_i$ being an unknown amplitude with low changes in time (or $\frac{\Delta a_i}{a^2_i} << 1$) and $h_i(t)$ an unknown warping function, the paper…

Methodology · Statistics 2020-05-18 Arman Kheirati Roonizi

We propose a new approach to measuring the agreement between two oscillatory time series, such as seismic waveforms, and demonstrate that it can be employed effectively in inverse problems. Our approach is based on Optimal Transport theory…

Geophysics · Physics 2022-07-01 Malcolm Sambridge , Andrew Jackson , Andrew P. Valentine

Dynamic Linear Models (DLMs) are commonly employed for time series analysis due to their versatile structure, simple recursive updating, ability to handle missing data, and probabilistic forecasting. However, the options for count time…

Methodology · Statistics 2023-06-30 Brian King , Daniel R. Kowal

Optical transient surveys continue to generate increasingly large datasets, prompting the introduction of machine-learning algorithms to search for quality transient candidates efficiently. Existing machine-learning infrastructure can be…

Temporal difference (TD) learning is a fundamental algorithm for estimating value functions in reinforcement learning. Recent finite-time analyses of TD with linear function approximation quantify its theoretical convergence rate. However,…

Machine Learning · Computer Science 2026-03-04 Yunxiang Li , Mark Schmidt , Reza Babanezhad , Sharan Vaswani

Trajectory optimization for autonomous vehicles usually relies on the kinematic bicycle model because of its computational simplicity. However, when the planned trajectory is executed under the true vehicle dynamics, which include lateral…

Robotics · Computer Science 2026-05-12 Lingxue Lyu , Zihui Liu

The paper considers distributed gradient flow (DGF) for multi-agent nonconvex optimization. DGF is a continuous-time approximation of distributed gradient descent that is often easier to study than its discrete-time counterpart. The paper…

Optimization and Control · Mathematics 2020-08-13 Brian Swenson , Ryan Murray , H. Vincent Poor , Soummya Kar

Drifting is an advanced driving technique where the wheeled robot's tire-ground interaction breaks the common non-holonomic pure rolling constraint. This allows high-maneuverability tasks like quick cornering, and steady-state drifting…

Robotics · Computer Science 2025-12-01 Feilong Jing , Yang Deng , Boyi Wang , Xudong Zheng , Yifan Sun , Zhang Chen , Bin Liang

We present a systematic approach for the semiclassical treatment of many-body dynamics of interacting, open spin systems. Our approach overcomes some of the shortcomings of the recently developed discrete truncated Wigner approximation…

Quantum Physics · Physics 2022-12-01 Christopher D. Mink , David Petrosyan , Michael Fleischhauer

Dynamical density functional theory (DDFT) has been successfully derived and applied to describe on the one hand passive colloidal suspensions, including hydrodynamic interactions between individual particles. On the other hand, active…

Statistical Mechanics · Physics 2016-01-18 Andreas M. Menzel , Arnab Saha , Christian Hoell , Hartmut Löwen

Multiple sequences alignment (MSA) is a traditional and challenging task for time-series analyses. The MSA problem is formulated as a discrete optimization problem and is typically solved by dynamic programming. However, the computational…

Machine Learning · Computer Science 2020-06-30 Keisuke Kawano , Takuro Kutsuna , Satoshi Koide

Deep Metric Learning (DML) loss functions traditionally aim to control the forces of separability and compactness within an embedding space so that the same class data points are pulled together and different class ones are pushed apart.…

Computer Vision and Pattern Recognition · Computer Science 2024-09-04 Michael G. DeMoor , John J. Prevost

Emerging applications in Printed Circuit Board (PCB) routing impose new challenges on automatic length matching, including adaptability for any-direction traces with their original routing preserved for interactiveness. The challenges can…

Hardware Architecture · Computer Science 2024-07-30 Weijie Fang , Longkun Guo , Jiawei Lin , Silu Xiong , Huan He , Jiacen Xu , Jianli Chen