CPL - Chalmers Publication Library
| Utbildning | Forskning | Styrkeområden | Om Chalmers | In English In English Ej inloggad.

Dynamically evolving Gaussian spatial fields

Anastassia Baxevani (Institutionen för matematiska vetenskaper, matematisk statistik) ; K. Podgorski ; Igor Rychlik (Institutionen för matematiska vetenskaper, matematisk statistik)
Extremes (1386-1999). Vol. 14 (2011), 2, p. 223-251.
[Artikel, refereegranskad vetenskaplig]

We discuss general non-stationary spatio-temporal surfaces that involve dynamics governed by velocity fields. The approach formalizes and expands previously used models in analysis of satellite data of significant wave heights. We start with homogeneous spatial fields. By applying an extension of the standard moving average construction we obtain models which are stationary in time. The resulting surface changes with time but is dynamically inactive since its velocities, when sampled across the field, have distributions centered at zero. We introduce a dynamical evolution to such a field by composing it with a dynamical flow governed by a given velocity field. This leads to non-stationary models. The models are extensions of the earlier discretized autoregressive models which account for a local velocity of traveling surface. We demonstrate that for such a surface its dynamics is a combination of dynamics introduced by the flow and the dynamics resulting from the covariance structure of the underlying stochastic field. We extend this approach to fields that are only locally stationary and have their parameters varying over a larger spatio-temporal horizon.

Nyckelord: Spectral density, Covariance function, Stationary second order, processes, Velocity field, significant wave height, mathematical-analysis, random noise, velocities, rainfall, seas



Den här publikationen ingår i följande styrkeområden:

Läs mer om Chalmers styrkeområden  

Denna post skapades 2011-05-24. Senast ändrad 2011-12-01.
CPL Pubid: 140991

 

Läs direkt!


Länk till annan sajt (kan kräva inloggning)


Institutioner (Chalmers)

Institutionen för matematiska vetenskaper, matematisk statistik (2005-2016)

Ämnesområden

Transport
Hållbar utveckling
Matematisk statistik

Chalmers infrastruktur