Ergodic theory of linear operators

Results 21 to 30 of about 166,394,816 (126)

Effect of Magnetic Islands on Neoclassical Heat Diffusivity in a Global Tokamak Simulation

Contributions to Plasma Physics, EarlyView.
ABSTRACT Resonant magnetic perturbations (RMPs) alter magnetic field topology via island formation and can modify core transport in toroidal fusion devices. Using the global gyrokinetic particle‐in‐cell code XGC‐S, originally developed for stellarator geometries, we quantify how island topology affects neoclassical heat transport in a circular tokamak ...
Joseph X. Li +5 more
wiley +1 more source

Machine Learning‐Assisted Design of BaTiO3‐Based Superparaelectric High‐Entropy Ceramics with Superior Energy Storage

ENERGY &ENVIRONMENTAL MATERIALS, EarlyView.
This study employed an adaptive iterative strategy combining machine learning algorithms, domain knowledge, experimental design, and experimental feedback to aim to precisely and quickly discover high‐entropy ceramics with excellent energy storage performance.
Haowen Liu +4 more
wiley +1 more source

Some Inequalities for the Euclidean Operator Radius of Two Operators in Hilbert Spaces [PDF]

, 2006
Some sharp bounds for the Euclidean operator radius of two bounded linear operators in Hilbert spaces are given. Their connection with Kittaneh’s recent results which provide sharp upper and lower bounds for the numerical radius of linear operators ...
Dragomir, Sever S
core +5 more sources

Forecasting Duration in High‐Frequency Financial Data Using a Self‐Exciting Flexible Residual Point Process

Journal of Forecasting, EarlyView.
ABSTRACT This paper presents a method for forecasting limit order book durations using a self‐exciting flexible residual point process. High‐frequency events in modern exchanges exhibit heavy‐tailed interarrival times, posing a significant challenge for accurate prediction.
Kyungsub Lee
wiley +1 more source

Scaling turbulence drives the general circulation

Quarterly Journal of the Royal Meteorological Society, EarlyView.
The NOAA Gulfstream SP4, which deployed the GPS dropsondes over the NE Pacific Ocean as part of the Winter Storms Project during the January–March periods of 2004, 2005 and 2006. Abstract Statistical multifractal analysis of airborne and dropsonde observations is used to show that persistence of velocity after molecular collisions breaks the continuous
Adrian F. Tuck
wiley +1 more source

Enhancing generalizability theory with mixed‐effects models for heteroscedasticity in psychological measurement: A theoretical introduction with an application from EEG data

British Journal of Mathematical and Statistical Psychology, EarlyView.
Abstract Generalizability theory (G‐theory) defines a statistical framework for assessing measurement reliability by decomposing observed variance into meaningful components attributable to persons, facets, and error. Classic G‐theory assumes homoscedastic residual variances across measurement conditions, an assumption that is often violated in ...
Philippe Rast, Peter E. Clayson
wiley +1 more source

Wave Tracing: Generalizing The Path Integral To Wave Optics

Computer Graphics Forum, EarlyView.
Abstract Modeling the wave nature of light and the propagation and diffraction of electromagnetic fields is crucial for the accurate simulation of many phenomena, yet wave simulations are significantly more computationally complex than classical ray‐based models.
Shlomi Steinberg, Matt Pharr
wiley +1 more source

Missing Values in Time Series: A Brief Review and a New Versatile Imputation Method

International Statistical Review, EarlyView.
Summary Missing data can significantly hamper standard time series analysis, yet they occur frequently in applications. In this paper, we briefly review some available methods for handling missing values and introduce the temporal Wasserstein imputation, a novel method for imputing missing data in time series.
Shuo‐Chieh Huang, Tengyuan Liang, Ruey S. Tsay +2 more
wiley +1 more source

A Note on Local Polynomial Regression for Time Series in Banach Spaces

Journal of Time Series Analysis, EarlyView.
ABSTRACT This work extends local polynomial regression to Banach space‐valued time series for estimating smoothly varying means and their derivatives in non‐stationary data. The asymptotic properties of both the standard and bias‐reduced Jackknife estimators are analyzed under mild moment conditions, establishing their convergence rates.
Florian Heinrichs
wiley +1 more source

Testing Distributional Granger Causality With Entropic Optimal Transport

Journal of Time Series Analysis, EarlyView.
ABSTRACT We develop a novel nonparametric test for Granger causality in distribution based on entropic optimal transport. Unlike classical mean‐based approaches, the proposed method directly compares the full conditional distributions of a response variable with and without the history of a candidate predictor.
Tao Wang
wiley +1 more source