Results 121 to 130 of about 1,407 (262)

Splitting fields of central simple algebras of exponent two

, 2016
: By Merkurjev's Theorem every central simple algebra of exponent two is Brauer equivalent to a tensor product of quaternion algebras. In particular, if every quaternion algebra over a given field is split, then there exists no central simple algebra of ...
Becher, Karim Johannes
core  

Subspace Acceleration for Efficient Nonlinear Water Wave Simulation

International Journal for Numerical Methods in Fluids, EarlyView.
We introduce an exponentially weighted subspace acceleration technique to reduce GMRES iterations for solving the Poisson equation with time‐dependent coefficients in nonlinear, dispersive free‐surface flows governed by the incompressible Navier‐Stokes equations. The method significantly reduces memory requirements and computational complexity compared
Rasmus Kleist Hørlyck Sørensen, Margherita Guido, Allan Peter Engsig‐Karup, Daniel Kressner   +3 more
wiley   +1 more source

Aggregating distributed energy resources for grid flexibility services: A distributed game theoretic approach

International Journal of Robust and Nonlinear Control, EarlyView., 2023
Abstract We propose a hierarchical energy management scheme for aggregating Distributed Energy Resources (DERs) for grid flexibility services. To prevent a direct participation of numerous prosumers in the wholesale electricity market, aggregators, as self‐interest agents in our scheme, incentivize prosumers to provide flexibility. We firstly model the
Xiupeng Chen, Mehran Shakarami, Jacquelien M. A. Scherpen, Nima Monshizadeh   +3 more
wiley   +1 more source

Assessing the Estimands and Estimates of Hospitalization Rates in Health Economics and Clinical Medicine

Health Economics, EarlyView.
ABSTRACT Even though data on hospital admissions are widely used in health research, hospitalization‐related estimands measured using these data are not always clearly conceptualized. Consequently, estimators of these quantities can have unclear rationales and undesirable properties.
Aditya Jain, Gil Peled, Filip Obradović, Federico Crippa, Yeshaya Nussbaum, Michael Gmeiner, Daniela P. Ladner, Charles F. Manski   +7 more
wiley   +1 more source

Evolutionary dynamics on a regular networked structured and unstructured multi‐population

International Journal of Robust and Nonlinear Control, EarlyView., 2023
Abstract In this paper, we study collective decision‐making in a multi‐population framework, where groups of individuals represent whole populations that interact by means of a regular network. Each group consists of a number of players and every player can choose between two options.
Wouter Baar, Leonardo Stella, Dario Bauso   +2 more
wiley   +1 more source

Robust Tests of Forecast Accuracy for Factor‐Augmented Regressions With an Application to the Novel EA‐MD‐QD Dataset

Journal of Applied Econometrics, EarlyView.
ABSTRACT We present four novel tests of equal predictive accuracy and encompassing á Pitarakis (2023, 2025) for factor‐augmented regressions. Factors are estimated using cross‐section averages (CAs) of grouped series and our theoretical findings are empirically relevant: asymptotic normality, robustness to an overspecification of the number of factors,
Alessandro Morico, Ovidijus Stauskas
wiley   +1 more source

Colourings of Uniform Group Divisible Designs and Maximum Packings

Journal of Combinatorial Designs, EarlyView.
ABSTRACT A weak c $c$‐colouring of a design is an assignment of colours to its points from a set of c $c$ available colours, such that there are no monochromatic blocks. A colouring of a design is block‐equitable, if for each block, the number of points coloured with any available pair of colours differ by at most one.
Andrea C. Burgess, Peter Danziger, Diane Donovan, Tara Kemp, James G. Lefevre, David A. Pike, E. Şule Yazıcı   +6 more
wiley   +1 more source

Signed Projective Cubes, a Homomorphism Point of View

Journal of Graph Theory, EarlyView.
ABSTRACT The (signed) projective cubes, as a special class of graphs closely related to the hypercubes, are on the crossroad of geometry, algebra, discrete mathematics and linear algebra. Defined as Cayley graphs on binary groups, they represent basic linear dependencies.
Meirun Chen, Reza Naserasr, Alessandra Sarti   +2 more
wiley   +1 more source

Stable Cuts, NAC‐Colourings and Flexible Realisations of Graphs

Journal of Graph Theory, EarlyView.
ABSTRACT A (2‐dimensional) realisation of a graph G $G$ is a pair ( G , p ) $(G,p)$, where p $p$ maps the vertices of G $G$ to R 2 ${{\mathbb{R}}}^{2}$. A realisation is flexible if it can be continuously deformed while keeping the edge lengths fixed, and rigid otherwise.
Katie Clinch, Dániel Garamvölgyi, John Haslegrave, Tony Huynh, Jan Legerský, Anthony Nixon   +5 more
wiley   +1 more source

Behavioral responses of black bears to human presence and infrastructure in Yosemite National Park

The Journal of Wildlife Management, EarlyView.
Using GPS collar data from black bears in Yosemite National Park, we examined how bear spatiotemporal activity in relation to human development shifted during the COVID‐19 park closure in 2020. In the absence of visitors, bears maintained consistent landscape‐scale space use but altered fine‐scale spatial and temporal behaviors.
Jennifer R. Green, Caitlin Lee‐Roney, Kathleen Patrick, Rachel Mazur, Robert Lester, Erin Degutis, Ryan Leahy, Tal Avgar, Naomi B. Schwartz, Kaitlyn M. Gaynor   +9 more
wiley   +1 more source