Results 121 to 130 of about 156,630 (288)

Matrix polynomials, generalized Jacobians, and graphical zonotopes

, 2015
A matrix polynomial is a polynomial in a complex variable $ $ with coefficients in $n \times n$ complex matrices. The spectral curve of a matrix polynomial $P( )$ is the curve $\{ ( , ) \in \mathbb{C}^2 \mid \mathrm{det}(P( ) - \cdot \mathrm{Id}) = 0\}$.
openaire   +2 more sources

Seasonal variations in planktonic food web structure affect stability by shifting the distribution of energy fluxes

Oikos, EarlyView.
Seasonality in temperate ecosystems shapes species phenology, influencing interactions and food web structure. Variations in species richness and biomass affect trophic interaction strength, a crucial factor for community stability, which can be assessed through energy fluxes – an essential indicator of ecosystem function.
Simon Bazin, Isabelle Domaizon, Cécilia Barouillet, Victor Frossard, Arnaud Sentis   +4 more
wiley   +1 more source

A Novel Method for Generating a Fused Ventilation–Perfusion Map Using CT‐Derived Ventilation and FDG‐PET for Lung Functional Avoidance in Radiotherapy: A Feasibility Study

Precision Radiation Oncology, EarlyView.
This study retrospectively analyzed two types of respiratory phase CT and PET/CT images of 20 lung cancer patients. After DIR and functional grading, three lung function images were developed, and their correlations and differences were evaluated. Abstract Background Pulmonary ventilation–perfusion function plays a crucial role in both radiotherapy ...
Suyan Bi, Zhitao Dai, Xingru Sun, Wan Fatihah Binti Wan Sohaimi, Ahmad Lutfi Bin Yusoff   +4 more
wiley   +1 more source

All‐sky assimilation impacts of the Tomorrow.io microwave sounder constellation on global weather forecasts

Quarterly Journal of the Royal Meteorological Society, EarlyView.
Key Findings: An assimilation methodology is established for the Tomorrow.io microwave sounder (TMS) flying on CubeSats in sun‐synchronous and inclined orbits, and in all cloud scenes. The TMS has a significant impact on weather forecast lead times up to 3 days in the Tropics in a research‐quality numerical weather prediction setting, and yields water ...
Jonathan J. Guerrette, Ryan Honeyager, Stephen Joseph Munchak, Xiaoxu Tian   +3 more
wiley   +1 more source

Assimilation of solar‐induced fluorescence satellite observations in the European Centre for Medium‐Range Weather Forecasts integrated forecast system

Quarterly Journal of the Royal Meteorological Society, EarlyView.
This work demonstrates the potential of the assimilation of satellite solar‐induced fluorescence (SIF) retrievals at eight‐day and 0.1° resolutions in the integrated forecast system (IFS), developed at the European Centre for Medium‐Range Weather Forecasts (ECMWF), at global scale, to provide a more realistic representation of the vegetation temporal ...
Sébastien Garrigues, Patricia de Rosnay, Peter Weston, Christoph Rüdiger, Cédric Bacour, David Fairbairn, Pierre Vanderbecken, Oscar Rojas‐Munoz, Ewan Pinnington, Anna Agusti‐Panareda, Souhail Boussetta, Jean‐Christophe Calvet, Richard Engelen   +12 more
wiley   +1 more source

Type Synthesis of Fully-decoupled Three-rotational and Three-translational Parallel Mechanism

Jixie chuandong, 2016
Through the analysis of the input and output characteristic of the full-coupled parallel mechanism,based on the theory of screws and the principle of individual driving,a method of structural synthesis of fully-decoupled three-translational and three ...
Zhou Hui, Cao Yi
doaj  

Bus Admittance Matrix Revisited: Performance Challenges on Modern Computers

IEEE Open Access Journal of Power and Energy
Bus admittance matrix is widely used in power engineering for network modeling. Being highly sparse, it requires fewer CPU operations when used for calculations. Meanwhile, sparse matrix calculations involve numerous indexing and scalar operations, which
Hantao Cui
doaj   +1 more source

Operational all‐sky assimilation of geostationary infrared water‐vapour channels in the regional ICON‐D2 model with an ensemble Kalman filter

Quarterly Journal of the Royal Meteorological Society, EarlyView.
Though many studies have shown potential benefit in assimilating all‐sky infrared radiances from geostationary satellites, at numerical weather prediction centres it is still common practice to assimilate clear‐sky radiances. We present the operationalization of the all‐sky assimilation of the spinning enhanced visible and infrared imager (SEVIRI ...
Annika Schomburg, Christoph Schraff, Christina Köpken‐Watts, Klaus Stephan, Liselotte Schühl, Robin Faulwetter   +5 more
wiley   +1 more source

Electromagnetic signal fast adversarial attack method based on Jacobian saliency map

Tongxin xuebao
In order to generate high-quality electromagnetic signal countermeasure examples, a fast Jacobian saliency map attack (FJSMA) method was proposed.The Jacobian matrix of the attack target class was calculated and feature saliency maps based on the matrix ...
Jian ZHANG, Xia ZHOU, Yiran ZHANG, Zicong WANG   +3 more
doaj   +2 more sources

Comparative Analysis of the Performances of a Nonlinear Observer and Nonlinear Kalman Filters in the Presence of Non‐Gaussian Disturbances

International Journal of Robust and Nonlinear Control, EarlyView.
ABSTRACT This paper focuses on state estimation for a fairly general class of systems, involving nonlinear functions and disturbances in both the process dynamics and output equations. A nonlinear observer that satisfies a H∞$$ {\boldsymbol{H}}_{\boldsymbol{\infty}} $$ disturbance attenuation constraint in addition to providing asymptotic stability in ...
Hamidreza Movahedi, Ali Zemouche, Rajesh Rajamani   +2 more
wiley   +1 more source