No abstract

An estimation-forecast setup for iceberg drift prediction ¡!-SPi-PI ¡?xmltex {=0pt=-3pt}?¿ SPi-PI-¿¡!-¡query id="q1"¿Your article is registered as a regular item and is being processed for inclusion in a regular issue of the journal. If this is NOT correct and your article belongs to a Special Issue/Collection please contact michael.evans@elsevier.com immediately prior to returning your corrections.¡/query¿-¿¡!-SPi-PI ¡?xmltex {=0pt=2pc}?¿ SPi-PI-¿¡!-¡query id="q2"¿The author names have been tagged as given names and surnames (surnames are highlighted in teal color). Please confirm if they have been identified correctly.¡/query¿-¿

No abstract

This article is concerned with the state estimation problem for linear systems with linear state equality constraints. We reexamine constrained Kalman filter variations and propose an alternative derivation of the optimal constrained Kalman filter for time variant systems. This results in an oblique state projection that gives the smallest error covariance. A simple example illustrates the performance of the different Kalman filters.

Ice management is an important cost driver for oil and gas developments in Arctic regions. In order to evaluate and test various ice management technologies, full-scale trials offshore north-east Greenland were performed in September 2012 and August 2013 within the framework of the Oden Arctic Technology Research Cruise (OATRC) program. This paper describes environmental conditions in the area of the trials, presents the OATRC program in general and discusses the sea ice management trials of OATRC 2013. Finally, numerical simulations of the Oden icebreaker in broken ice conditions are performed based on the field data. Qualitative comparisons of the simulations with full-scale observations indicate further future potential of the suggested numerical approach.